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Exercise, Weight Loss, and the Fat Burning Zone

FitSugar — Tue, 17 Nov 2009 05:50:01 -0800

Much has been made of late about exercise and its relation to weight loss. There was the Time cover story The Myth About Weight Loss and a recent article on the topic in the New York Times, which recommended working out in the fat burning zone.

You see the phrase on all types of cardio machines: the fat burning zone, aka the "weight loss zone," means working out at a lower intensity to burn fat as fuel. But these workouts also burn considerably fewer calories. I was confused about how we should all be spending our cardio time, so I took my questions to exercise physiologist Jason Karp, who also happens to be an avid runner.

When I asked him if we should all be scaling our workouts back and aiming for the fat burning zone, Karp explained that it's not the type of fuel your body is burning, but the overall calories that count. "It doesn't matter if you're using fat or carbohydrates. In order to lose fat from your waistline you don't have to be using fat as fuel during workout," he said. He offered up the example of sprinters; they don't train in the fat burning zone, but they're mighty trim in the torso. Losing weight comes down to math - you want to be in a calorie deficit to shed pounds and body fat. Higher intensity exercise puts you at a higher burn rate. To burn the most calories in a cardio workout, skip past the fat burning zone and work out with more intensity. To really burn up calories, Karp recommends intervals. To learn why, read more.

Essentially, interval workouts give you the most bang for your sweat buck. Karp explains that with "intense exercise you're pushing your body more out of homeostasis," that is, the equilibrium of energy the body prefers to maintain. During the few hours after an interval workout, the body must go through a recovery period, and a lot needs to happen to return to the body to pre-exercise levels. "You've got to drop the heart rate, synthesize glycogen for the muscles, remove lactate from muscle and take it to the liver," says Karp. All these actions require energy, which raises the metabolic rate for many hours after exercising. Thirty minutes of exercise at a low intensity doesn't place nearly as much stress on the body as intervals, so you burn fewer calories both during and after the workout.

Before you hit the track and start running intervals, Karp recommends building a strong cardiovascular fitness base and working with a trainer for guidance. Even if you're not ready for sprints, play with your speed during your next cardio session. Slow and steady might win the race, but intervals will burn more calories.

Source: Flickr User pistoldrawn

Low Resting Heart Rate?

FitSugar — Tue, 09 Jan 2007 02:00:00 -0800

Have you noticed that since working out your resting heart rate is lower than it was? This is no cause for alarm as most athletes (yup, you're an athlete now) generally have low heart rates.

Runner's World gives us this analogy:

...consider a bricklayer lifting bricks. If his arm muscles are strong from lifting lots of bricks, he can move 10 bricks with each lift rather than just two or three. Similarly, if your heart muscle is strong thanks to running, it has a higher stroke volume, which means that it can pump more blood with each beat than an untrained heart. It can also pump the same amount of blood in a minute using fewer beats.

The average resting heart rate of adults is 60-100 beats per minute (bpm) while athletes are around 50-60 bpm. Other numbers to know: The infant/neonatal rate of heartbeat is 130-150 bpm, the toddler's is 100–130 bpm, the older child's is 90–110 bpm and the adolescent's is 80–100 bpm.

The worry would (and should) come in when a resting heart rate is lower than 30. However, even that can be completely normal (and usually is) if the athlete is totally healthy. The slow heart rate usually just indicates a strong heart. If you are concerned, it never hurts to consult a physician when dealing with your health.

Fit's Tip: The best time to determine your resting heart rate is when you first awaken in the morning or after sitting down and relaxing for at least 5 minutes. Get a heart rate monitor to monitor your heart while working out. Don't know your target heart rate? Check out the Fit Calculator to find out!

Is Running While Pregnant Safe?

FitSugar — Tue, 20 Oct 2009 08:00:52 -0700

It's not every day that you see a pregnant woman going for a run, like Miss Kourtney Kardashian here. On her hour-long jog, I'm sure she got some stares and whispers. Not just because she's famous, but because she's got a big bun in the oven. They're probably wondering, is this safe for her baby, and safe for mom?

Regular exercise is encouraged by doctors for those expecting, because it can help a woman stay healthy, and alleviate some of the discomforts like stiffness, back pain, leg cramping, or constipation. Working out can also prevent unnecessary weight gain, relieve stress, and get a woman ready to endure the physical challenges of labor.

With that said, there are some guidelines a pregnant woman should follow when working out.

Don't make any big changes to your exercise program once you become pregnant. If you were running regularly before you conceived, then it's safe to keep it up, as long as it feels good and you don't overdo it. If you want to start a new type of exercise, talk to your doc first.
Be OK with modifying your routine, especially as your pregnancy progresses. If you used to run four miles a day, you may find that you'll need to cut down in the beginning of your pregnancy. And once you're in the end of your second trimester, or third, walking may be best.
Don't do any types of exercise that put you or the baby at risk, like extreme sports that require balance, speed, or could result in you falling. Your doctor will probably recommend you save the surfing, skiing, horseback riding, biking outdoors, and rock climbing for after delivery.

For the rest keep reading

Heart failure

FitSugar — Wed, 08 Oct 2008 17:35:10 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Permanent Implantable Heart Approved

In 2006, the FDA approved the first permanent artificial heart. The AbiCor is intended for patients who are not eligible for heart transplants and who are only expected to survive about a month without medical treatment. Patients who received the AbiCor have survived, on average, about 5 months.

Statin Drug Approved for Heart Failure

In 2006, the FDA approved the cholesterol drug atorvastatin (Lipitor) to reduce the risks of hospitalization for heart failure in patients with heart disease.

Drug Research

The investigational drug tolvaptan improved symptoms in patients hospitalized with severe heart failure and fluid build-up in the lungs, according to several 2007 Journal of the American Medical Association (JAMA) studies. However, the drug did not reduce the risks of re-hospitalization and death.

Preserved Versus Reduced Ejection Fraction

Heart failure with preserved left-ventricular ejection fraction (LVEF) is becoming more common, suggests several 2006 studies published in JAMA and the New England Journal of Medicine. Unfortunately, this type of heart failure is less well studied than reduced LVEF. Experts are urging that more studies be conducted to determine better treatment options for preserved LVEF. Both types of heart failure have high mortality rates.

Systolic Blood Pressure Predictor of Mortality

Patients who are admitted to the hospital with heart failure and low systolic blood pressure have a poorer chance of survival than patients admitted with high blood pressure, indicates a 2006 JAMA study.

Diet and Lifestyle Factors

Daily consumption of whole-grain breakfast cereals may reduce the risk for heart failure, suggests research presented at a 2007 American Heart Association conference on heart disease prevention.
A drink or two a day is associated with lower risk of heart failure, indicates a 2006 Journal of the American College of Cardiology study. However, heavy alcohol consumption can increase the risk for heart failure.

Introduction

To understand what occurs in heart failure, it is useful to be familiar with the anatomy of the heart and how it works. The heart is composed of two independent pumping systems, one on the right side, and the other on the left. Each has two chambers, an atrium and a ventricle. The ventricles are the major pumps in the heart.

The external structures of the heart include the ventricles, atria, arteries, and veins. Arteries carry blood away from the heart while veins carry blood into the heart. The vessels colored blue indicate the transport of blood with relatively low content of oxygen and high content of carbon dioxide. The vessels colored red indicate the transport of blood with relatively high content of oxygen and low content of carbon dioxide.

The Right Side of the Heart. The right system receives blood from the veins of the whole body. This is "used" blood, which is poor in oxygen and rich in carbon dioxide.

The right atrium is the first chamber that receives blood.
The chamber expands as its muscles relax to fill with blood that has returned from the body.
The blood enters a second muscular chamber called the right ventricle.
The right ventricle is one of the heart's two major pumps. Its function is to pump the blood into the lungs.
The lungs restore oxygen to the blood and exchange it with carbon dioxide, which is exhaled.

The Left Side of the Heart. The left system receives blood from the lungs. This blood is now oxygen rich.

The oxygen-rich blood returns through veins coming from the lungs (pulmonary veins) to the heart.
It is received from the lungs in the left atrium, the first chamber on the left side.
Here, it moves to the left ventricle, a powerful muscular chamber that pumps the blood back out to the body.
The left ventricle is the strongest of the heart's pumps. Its thicker muscles need to perform contractions powerful enough to force the blood to all parts of the body.
This strong contraction produces systolic blood pressure (the first and higher number in blood pressure measurement). The lower number ( diastolic blood pressure) is measured when the left ventricle relaxes to refill with blood between beats.
Blood leaves the heart through the ascending aorta, the major artery that feeds blood to the entire body.

The Valves. Valves are muscular flaps that open and close so blood will flow in the right direction. There are four valves in the heart:

The tricuspid regulates blood flow between the right atrium and the right ventricle.
The pulmonary valve opens to allow blood to flow from the right ventricle to the lungs.
The mitral valve regulates blood flow between the left atrium and the left ventricle.
The aortic valve allows blood to flow from the left ventricle to the ascending aorta.

Click the icon to see an image of the internal structures of the heart.

The Heart's Electrical System. The heartbeats are triggered and regulated by the conducting system, a network of specialized muscle cells that form an independent electrical system in the heart muscles. These cells are connected by channels that pass chemically caused electrical impulses.

Click the icon to see an image of the conduction system of the heart.

Heart failure is not a disease. It is a condition or process in which the heart is unable to pump enough blood to meet the needs of the body's tissues. The heart doesn't "fail" in the sense of ceasing to beat (as occurs during a heart attack). Rather, it weakens, usually over the course of months or years, so that it is unable to pump out all the blood that enters its chambers. As a result, fluids tend to build up in the lungs and tissues, causing congestion. This condition used to be called "congestive heart failure," but the name was officially changed to heart failure in 2005.

Ways the Heart Can Fail. Heart failure can occur in several ways:

The muscles of the heart pumps (ventricles) become thin and weakened. They stretch (dilate) to the extent that they cannot pump the blood with enough force to reach all the body's tissues.
The heart muscles stiffen or thicken. Here, they lose elasticity and cannot relax. Insufficient blood enters the chamber, so not enough blood is pumped out into the body to serve its needs.
Sometimes the valves of the heart are abnormal. (Valves open or close to control the flow of blood entering or leaving the heart). They may narrow, such as in aortic stenosis, causing a back up of blood, or they may close improperly so that blood leaks back into the heart. The mitral valve (which regulates blood flow between the two chambers on the left side of the heart) often becomes leaky in severe heart failure -- a condition called mitral regurgitation.

Click the icon to see an image of the valves of the heart.

The very mechanisms that the body uses to compensate for inefficient heart pumping can, over time, change the architecture of the heart (called remodeling) and finally lead to irreversible problems.

The specific effects of heart failure on the body depend on whether it occurs on the left or right side. Over time, however, in either form of heart failure, the organs in the body do not receive enough oxygen and nutrients, and the body's wastes are removed slowly. Eventually, vital systems break down.

Failure on the Left Side (Left-Ventricular Heart Failure). Failure on the left side of the heart is more common than failure on the right side. The failure can be a result of abnormal systolic (contraction) or diastolic (relaxation) action:

Systolic. Systolic heart failure is a pumping problem. In systolic failure, the heart muscles weaken and cannot pump enough blood throughout the body. The left ventricle is usually stretched (dilated). Fluid backs up and accumulates in the lungs (pulmonary edema). Systolic heart failure typically occurs in men between the ages of 50 - 70 years who have had a heart attack.
Diastolic. Diastolic heart failure is a filling problem. When the left ventricle muscle becomes stiff and cannot relax properly between heartbeats, the heart cannot fill fully with blood. When this happens, fluid entering the heart backs up. This causes the veins in the body and tissues surrounding the heart to swell and become congested. Patients with diastolic failure are typically women, overweight, and elderly, and have high blood pressure and diabetes.

Failure on the Right Side (Right-Ventricular Heart Failure). Failure on the right side of the heart is most often a result of failure on the left. Because the right ventricle receives blood from the veins, failure here causes the blood to back up. As a result, the veins in the body and tissues surrounding the heart to swell. This causes swelling in the feet, ankles, legs, and abdomen.

Ejection Fraction. To help determine the severity of left-sided heart failure, doctors use an ejection fraction (EF) calculation, also called a left-ventricular ejection fraction (LVEF). This is the percentage of the blood pumped out from the left ventricle during each heartbeat. An ejection fraction of 50 - 75% is considered normal. Patients with left-ventricular heart failure are classified as either having a preserved ejection fraction (greater than 50%) or a reduced ejection fraction (less than 50%).

In general, systolic heart failure has been thought to be associated with a reduced ejection fraction, whereas diastolic heart failure was associated with a preserved (normal) ejection fraction. However, several 2006 studies indicated that diastolic heart failure can occur regardless of the ejection fraction, although it is more common in patients with a preserved ejection fraction. Mortality rates among patients with reduced LVEF and preserved LVEF are similar.

Although reduced LVEF heart failure is better studied, and its treatment goals more clearly defined, several important 2006 studies suggest that preserved LVEF heart failure is becoming increasingly common. The studies, published in the Journal of the American Medical Association and the New England Journal of Medicine, indicated that patients with preserved LVEF heart failure are more likely to be female and older, and have a history of high blood pressure and atrial fibrillation (a disturbance in heart rhythm). Experts are now urging that more studies focus on patients with preserved LVEF so that better treatment options can be established.

Causes

Heart failure has many causes and can evolve in different ways.

It can be a direct, last-stage result of heart damage from one or more of several heart or circulation diseases.
It can occur over time as the heart tries to compensate for abnormalities caused by these conditions, a condition called remodeling.

In all cases, the weaker pumping action of the heart means that less blood is sent to the kidneys. The kidneys respond by retaining water and salt. This in turn increases edema (fluid buildup) in the body, which causes widespread damage.

Uncontrolled high blood pressure (hypertension) is also a major cause of heart failure even in the absence of a heart attack. In fact, about 75% of cases of heart failure start with hypertension. It generally develops as follows:

The heart muscles thicken to make up for increased blood pressure.
The force of the heart muscle contractions weaken over time, and the muscles have difficulty relaxing. This prevents the normal filling of the heart with blood.

[See In-Depth Report #14:High blood pressure.]

Hypertension is a disorder characterized by consistently high blood pressure. Generally, high blood pressure consists of systolic blood pressure (the "top" number, which represents the pressure generated when the heart beats) higher than 140, or diastolic blood pressure (the "bottom" number, which represents the pressure in the vessels when the heart is at rest) over 90.

Coronary artery disease is the end result of a complex process called atherosclerosis (commonly called "hardening of the arteries"). It is the most common cause of heart attack and involves the build-up of unhealthy cholesterol in the arteries, with inflammation and injury in the cells of the blood vessels. The arteries narrow and become brittle. Heart failure in such cases most often results from a pumping defect in the left side of the heart. [See In-Depth Report #3: Coronary artery disease and angina ; and In-Depth Report #23: Cholesterol.]

Click the icon to see an image of atherosclerosis.

People now often survive heart attacks, but eventually many develop heart failure from the physical damage done to the heart muscles by the attack. Ironically, heart attack recovery is probably one of the major factors in the dramatic increase in heart failure cases over the past decade. On an encouraging note, however, new therapies that are reducing the severity of heart attacks may help stabilize heart failure rates. [See In-Depth Report #12: Heart attack.]

The valves of the heart control the flow of blood leaving and entering the heart. Abnormalities can cause blood to back up or leak back into the heart.

Click the icon to see an image of the heart valves.

In the past, rheumatic fever, which scars the heart valves and prevents them from closing, was a major cause of death from heart failure. Fortunately, antibiotics have relegated this disease to a minor cause of heart failure. Birth defects may also cause abnormal valvular development. Although more children born with heart defects are now living to adulthood, they still face a higher than average risk for heart failure as they age.

Cardiomyopathy is disease that damages the heart muscles and leads to heart failure. There are several different types. Injury to the heart muscles may cause the heart muscles to thin out (dilate) or become too thick (become hypertrophic). In either case, the heart doesn't pump correctly.

Dilated Cardiomyopathy. Dilated cardiomyopathy involves an enlarged heart ventricle. The muscles thin out, reducing the pumping action, usually on the left side. Although this condition is associated with genetic factors, the direct cause often is not known. (This is called idiopathic dilated cardiomyopathy.) Research strongly indicates that viruses, such as Coxsackie virus, or other infections may be at the base of this condition. Experts think that an autoimmune response occurs in which infection-fighting antibodies attack a person's own proteins in the heart, mistaking them for foreign substances.

Click the icon to see an image of dilated cardiomyopathy.

Hypertrophic Cardiomyopathy. In hypertrophic cardiomyopathy, the heart muscles become thick and contract with difficulty. Some research indicates that this occurs because of a genetic defect that causes a loss of power in heart muscle cells and, subsequently, lower pumping strength. To compensate for this power loss, the heart muscle cells grow. This condition, rare in the general population, is often the cause of sudden death in young athletes.

Click the icon to see an image of hypertrophic cardiomyopathy.

High blood pressure, heart attacks, or other initial processes that impair the pumping actions of the heart trigger a number of hormonal and neurochemical mechanisms to correct imbalances in pressure and blood flow. Unfortunately, while these corrective responses help in the short term, they increase the work of the heart. The mechanisms are now viewed as major contributors to the end stages of heart failure. Some are described briefly in the following sections.

Remodeling. The heart responds to high blood pressure and overload by enlarging in order to increase blood input. This leads to structural damage called remodeling:

In order to accommodate the increased blood input, the heart muscle cells elongate. The muscular walls of the heart that they form become thinner and inefficient.
The muscle cells undergo other changes that result in calcium loss. Calcium is a mineral that is crucial for healthy heart contractions.
The thinner heart muscles and the impaired heart contractions further weaken the heart's pump.
Mitral valve regurgitation is a possible outcome of remodeling. The mitral valve regulates blood flow between the two chambers on the left side of the heart. In response to remodeling, the structural changes in the heart may distort the mitral valve so that the blood leaks backward into the left atrium of the heart instead of flowing out into the body's circulation.
These changes are generally irreversible, although heart pacemakers and certain drugs, including beta-blockers and ACE inhibitors, may reverse some of the remodeling in some patients.

Activation of the Sympathetic Nervous System. The sympathetic nervous system consists of the nerve cells that automatically govern and regulate the beating heart.

This nervous system responds to the failing heart pump by signaling the release of stress hormones, in particular a powerful one called norepinephrine.
These hormones flood the heart, causing it to beat even faster.
These rapid heart beats, although intended to accommodate the weakened pumping actions, only accelerate the damage.

The Renin-Angiotensin-Aldosterone System (RAAS). The renin-angiotensin-aldosterone system (RAAS) is a group of hormones that are responsible for the opening and narrowing of blood vessels and retention of fluids. They also affect cell development in the heart.

The RAAS hormones are called into action by the failing heart.
They respond to the lower blood volume of the weakened heart by constricting the blood vessels and retaining fluids and sodium.
The heart then works harder to pump blood through these narrowed vessels. Blood pressure, then, is forced to increase, which creates a vicious cycle.

Immune System Response. The immune system may also compound the damage. In response to injury in the heart muscle cells or in other parts of the body that occurs as the heart fails, the immune system releases factors intended to protect these areas.

In excess, however, they can cause inflammation and damage.

The most important of these factors are called cytokines. Active cytokines include tumor necrosis factor (TNF) and possibly interleukins 1 and 6.
High levels of these cytokines have been observed in patients with the most severe classes of heart failure.
They may play an important role in the process leading to remodeling. High levels of these cytokines may actually trigger muscle cell growth and enlargement of the heart.

Other Players. Other molecules or compounds have been identified that might play a positive or negative role in the process of the failing heart.

Natriuretic peptides are a family of compounds released to counterbalance the effects of RAAS. Atrial natriuretic peptide (ANP) is a specific member of this family that opens blood vessels and counteracts the sodium-retaining properties of aldosterone (one of the RAAS hormones). It is of particular interest to researchers looking for new treatments.
Endothelin is a powerful protein involved in blood vessel constriction, cell proliferation and build-up, and other negative effects on the heart.
Nitric oxide is important for blood vessel dilation and elasticity.

Symptoms

Many symptoms of heart failure result from the congestion that develops as fluid backs up into the lungs and leaks into the tissues. Other symptoms result from inadequate delivery of oxygen-rich blood to the body's tissues. Since heart failure can progress rapidly, it is essential to consult a doctor immediately if any of the following symptoms are detected.

Fatigue and shortness of breath (dyspnea) are the first symptoms. They are caused by fluid in the lungs. Patients typically report that they feel out of breath after mild exertion. It is unlike the breathlessness of angina, which feels like a heavy weight pressing on the chest.

Fluid retention. Patients may complain of leg or abdominal swelling.
Wheezing or cough. Patients may have asthma-like wheezing or a dry hacking cough that occurs a few hours after lying down, but then stops after the patient sits up.
Central sleep apnea. This disorder results when the brain fails to signal the muscles to breathe during sleep. It occurs in up to half of people with heart failure. Sleep apnea causes disordered breathing at night. If heart failure progresses, the apnea may be so acute that a person, unable to breathe, may awaken from sleep in panic.
Loss of muscle mass. Over time, patients may lose muscle weight due to low cardiac output.

Ultimately, fluid in the lungs may build up. This is called pulmonary edema. When this happens, symptoms become more severe.

In addition to shortness of breath, patients sometimes have a cough that produces a pinkish froth.
Patients may experience a bubbling sensation in the lungs and feel as if they are drowning.
Typically, the skin is clammy and pale, sometimes nearly blue. This is a life-threatening situation, and the patient must go immediately to an emergency room.

Fatigue. As with left-side heart failure, an early symptom of right-side (right-ventricular) failure is extreme tiredness.
Fluid accumulation. This first occurs in the feet, then the ankles and legs, and finally in the abdomen. The liver may also be enlarged.
Weight gain. Although appetites are often depressed, patients with heart failure gain weight because they retain salt and water.
Loss of muscle mass.

Risk Factors

Nearly 5 million Americans currently suffer from heart failure. About 550,000 new cases of heart failure are now diagnosed each year. In 1970 there were only 250,000 new cases, so the annual numbers have risen dramatically. Such numbers represent an increasingly older population. Although there has been a dramatic increase over the last several decades in the number of people who suffer from heart failure, survival rates have been improving greatly.

Coronary artery disease and high blood pressure are the main causes of heart failure. Other diseases that damage or weaken the heart muscle or heart valves can also cause heart failure. Heart failure is most common in people over age 65, African-Americans, and women.

Heart failure is the most common reason for hospitalization in the elderly, and as the population ages, the incidence of heart failure is rising dramatically. According to one report, it occurs at a rate of about 10 in 1,000 people after age 65. The positive implication is, however, that people are living longer with heart failure.

Men are at higher risk for heart failure than women, although the difference narrows with age. Women also have a better survival rate than men do when heart failure is caused by valvular heart disease, high blood pressure, or alcohol abuse. (Some studies indicate that this is because men may be more susceptible to the process of heart muscle-cell remodeling, a damaging effect of hypertension.)

The survival rates of women and men are more similar, however, when heart failure evolves from coronary artery disease or heart attack. Women are much more likely to develop heart failure after a heart attack than men. In such cases, some evidence suggests that the reasons for this may include less aggressive approach to treatment for the initial heart conditions.

African-Americans are at higher risk for heart failure than Caucasians, and studies have reported that they tend to do much worse. In a 2003 study, however, in which Caucasians and African-Americans had comparable treatment, African-Americans actually had lower 1-year mortality rates (with slightly higher rates of rehospitalizations). Some evidence suggests that African-Americans are more often likely than Caucasians to develop diastolic heart failure (a failure of the heart muscle to relax normally), which is often a precursor to systolic heart failure (impaired ability to pump blood). Caucasians tend to develop systolic heart failure first.

According to a 2006 New England Journal of Medicine study, people whose parents had heart failure have a greatly increased risk of developing heart failure, particularly left-ventricular systolic heart failure. Earlier studies have suggested that a family history of early heart failure caused by cardiomyopathies (diseases that damage the heart muscle) may also predispose people to the disease. Researchers are looking for changes in specific genes that might regulate systems involved in heart failure and so increase susceptibility in certain populations.

Chronic alcohol abuse can damage the heart muscles, can cause hypertension, and may prove to be one cause of idiopathic dilated cardiomyopathy. Moderate alcohol consumption, on the other hand (generally defined as 2 drinks a day for men and 1 drink for women), may protect against heart failure. Non-drinkers, though, are not advised to begin drinking.

Coronary artery disease. More than 60% of heart failure cases may be due to coronary artery disease and its risk factors (smoking, sedentary living, obesity).
Heart attack. The injured heart after an attack is at high risk for failure. The improved survival rates from heart attack over the past decades have actually been responsible for the dramatic increase in heart failure rates.
High blood pressure. Hypertension is a significant risk factor and is present in 75% of patients with heart failure.
Diabetes. People with diabetes are at high risk for heart failure, particularly if they also have coronary artery disease. Even blood sugar abnormalities that precede diabetes increase the risk.
Obesity. Obesity is associated with both hypertension and type 2 diabetes, conditions that place people at risk for heart failure. Evidence strongly suggests that obesity itself is a major risk factor for heart failure, particularly in women. In a major 2002 study, about 14% of heart failure cases in women and 11% in men could be attributed to obesity. Both overweight and obese women had a significantly higher than normal risk for heart failure. Only obesity led to a significant risk in men.
Valvular heart disease. Specific valvular conditions that are common in patients with heart failure include aortic stenosis and mitral regurgitation.
Severe emphysema. Chronic obstructive pulmonary disease is a major risk factor for right-side heart failure.

Emphysema is a lung disease involving damage to the air sacs (alveoli).There is progressive destruction of alveoli and the surrounding tissue that supports them. As the disease gets worse, large air cysts take the place of normal lung tissue. Air is trapped in the lungs.

Cardiomyopathies due to various causes, including birth defects, HIV infection, and other infections.
In rare cases, heart failure can occur in women around the time of childbirth, a condition called peripartum cardiomyopathy.

Click the icon to see an image of peripartum cardiomyopathy.

An overactive thyroid (hyperthyroidism) or underactive thyroid (hypothyroidism) can have severe effects on the heart and increase the risk for heart failure.
Amyloidosis. A starchy protein (amyloid) that builds up in tissues and organs can lead to heart failure.
Surviving childhood cancers. Survivors face a risk for developing heart failure in later years, particularly those treated with chemotherapies such as doxorubicin. Newer cancer advances may reduce this risk.
Acute myocarditis. This rare viral infection involves the heart muscle and can produce temporary but potentially life-threatening heart failure.

Long-term use of anabolic steroids (male hormones used to build muscle mass) increases the risk for heart failure. The drug itraconazole (Sporanox), used to treat skin, nail, or other fungal infections, has been linked to heart failure. In 2006, the FDA warned that the cancer drug imatinib (Gleevec) has been associated with heart failure cases. Most patients who took imatinib and developed heart failure had a history of diabetes, high blood pressure, or heart disease.

Complications

At least 20% of hospitalizations in older adults are due to heart failure. For people over age 65, it is the number one cause of death, with nearly 290,000 people dying from this disease each year. Nevertheless, although heart failure produces very high mortality rates, treatment advances in hypertension, heart surgeries, and heart pacemakers are improving survival rates.

The most serious and life-threatening complications of heart failure are:

Arrhythmias (irregular beatings of the heart)
Acute pulmonary edema (fluid in the lungs)

Left-side heart failure tends to be more severe than right-side heart failure, particularly when it is associated with the following conditions:

Coronary artery disease
HIV infection
Amyloidosis (a metabolic disorder than can lead to organ failure)
Chemotherapy that uses the drug doxorubicin

The outlook is better in patients with left-side heart failure associated with:

Idiopathic cardiomyopathy (the cause is unknown)
Heart failure due to childbirth

Weight Issues. If patients with heart failure are overweight to begin with, their condition tends to be more severe. Once heart failure develops, however, an important indicator of a worsening condition is the occurrence of cardiac cachexia, which is unintentional rapid weight loss (a loss of at least 7.5% of normal weight within 6 months).

Impaired Kidney Function. Heart failure weakens the heart’s ability to pump blood. This can affect other parts of the body including the kidneys (which in turn can lead to fluid build-up). Decreased kidney function is common in patients with heart failure, both as a complication of heart failure and as a complication of other diseases associated with heart failure (such as diabetes). Studies suggest that in patients with heart failure, impaired kidney function increases the risks for heart complications including hospitalization and death.

Congestion (Fluid Buildup). In left-sided heart failure, fluid builds up first in the lungs. Later, as right-sided heart failure develops, fluid builds up in the legs, feet, and abdomen. According to one study, patients with severe symptoms who had congestion (fluid buildup) had poorer survival rates than those without fluid build up. Two-year survival rates were 87% in those who were congestion-free compared to 41 - 67% in patients with various signs of congestion (such as swelling, difficulty breathing when lying down, and weight gain from fluid buildup). Fluid buildup is treated with lifestyle measures, such as reducing salt in the diet, as well as drugs, such as diuretics. Sometimes, for hospitalized patients, an ultrafiltration device is used to remove excess water and salt from the body (see Surgery and Devices).

Atrial Fibrillation. This abnormal rhythm is a rapid quivering beat in the upper chambers of the heart. It is a major cause of stroke and very dangerous in people with heart failure.

Left Bundle Branch Block. Left bundle-branch block is an abnormality in electrical conduction in the heart. It develops in about 30% of patients with heart failure and is a major risk factor for serious adverse heart events.

Systolic Blood Pressure. An important 2006 study indicated that patients who arrive at the hospital with heart failure and low systolic blood pressure have a poorer prognosis than those who arrive with high systolic blood pressure. Researchers think that high systolic blood pressure may be a signal for unique clinical characteristics.

Sleep Apnea. With this disorder, a person stops breathing during the night, perhaps hundreds of times, usually for periods of 10 seconds or longer. It is a very strong risk factor for heart failure, and patients with apnea have a higher mortality rate than those who do not.

Depression. The presence of depression indicates a poorer outlook for the heart. Studies indicate that depression may have adverse biologic effects on the immune and nervous systems, blood clotting, blood pressure, blood vessels, and heart rhythms.

Seasonal and Daily Patterns. Studies have shown that more emergency room visits and higher mortality rates occur during winter months and on Mondays in patients with heart failure. One factor in this higher risk may be sudden and strenuous exertion, particularly snow-shoveling, which is associated with a risk for heart attack in people with heart problems.

Diagnosis

Doctors can often make a preliminary diagnosis of heart failure by medical history and careful physical examination.

The medical history risks for heart failure include:

High blood pressure
Diabetes
Poor cholesterol levels
Heart or peripheral vascular disease
Sleep apnea
Thyroid problems
Obesity
Lifestyle factors (smoking, alcohol use)

The following physical signs, along with medical history, strongly suggest heart failure:

Enlarged heart
Irregular heart sounds
Abnormal sounds in the lungs
Swelling or tenderness of the liver
Fluid retention in legs and abdomen
Elevation of pressure in the veins of the neck

Both blood and urine tests are used to check for problems with the liver and kidneys and to detect signs of diabetes. Lab tests can measure:

Cholesterol and lipid levels
Blood sugar (glucose)
Red blood cell count (to rule out anemia)
Blood sugar levels
Thyroid function

Urine tests can be used to assess the presence of a protein called albumin. Albumin in the urine is usually a sign of kidney disease, but even tiny amounts (microalbumin) signal an increased risk for heart failure in people with and without diabetes.

The exercise stress test measures heart rate, blood pressure, and oxygen consumption while a patient is performing physically, usually walking on a treadmill. It is an important diagnostic component in determining heart failure symptoms. Doctors also use exercise tests to gauge long-term outlook and the effects of particular treatments.

An electrocardiogram (ECG) cannot diagnose heart failure, but it can indicate underlying heart problems. It is sometimes called an EKG. The test is simple and painless to perform. It may be used to diagnose:

Enlargement of the heart muscle, which may help to determine long-term outlook
The presence of coronary artery disease
Abnormal cardiac rhythms. A rhythm pattern called a prolonged QT interval, for example, might predict people with heart failure who are at risk for severe complications and would need more aggressive therapies.

The major benefit of an ECG is that it can help determine which patients do not need an echocardiogram, a more accurate (but more expensive) diagnostic test.

The electrocardiogram (ECG, EKG) is used extensively to diagnose heart disease, from congenital heart disease in infants to myocardial infarction and myocarditis in adults. There are several different types of electrocardiograms.

The best diagnostic test for heart failure is echocardiography. Echocardiography is a noninvasive, entirely safe test that uses ultrasound to image the heart as it is beating. Cardiac ultrasounds provide the following information:

Accurate indications of valve function
The amount of blood flow through the heart's chambers
The location of the failure and where it has occurred

Doctors use information from the echocardiogram for calculating the ejection fraction (how much blood is pumped out during each heartbeat), which is important for determining the severity of heart failure.

Radionuclide Ventriculography. Radionuclide ventriculography is an imaging technique that uses a tiny amount of radioactive material (called a trace element). The substance is injected into a patient. As it passes through the bloodstream it is picked up on x-rays. This is a very important imaging technique for patients with heart failure. It is very sensitive in revealing heart enlargement or evidence of fluid accumulation around the heart and lungs. It is typically used in concert with angiography.

Magnetic Resonance Imaging. Magnetic resonance imaging (MRI) scans that use contrast dyes to improve resolution are proving helpful for identifying patients with irreversible heart damage. Damage appears as very bright areas on the scan.

Doctors may recommend angiography if they suspect that blockage of the arteries is contributing to heart failure. This procedure is invasive.

A thin tube called a catheter is inserted into one of the large arteries in the arm or leg.
It is gently guided through the artery until it reaches the heart.
The catheter measures internal blood pressure at various locations, giving the doctor a comprehensive picture of the extent and nature of the heart failure.
Dye is then injected through the tube into the heart.
X-rays called angiograms are taken as the dye moves through the heart and arteries.
These images help locate problems in the heart's pumping action or blockage in the arteries.

Major complications of angiography are rare (about 0.1%) but can occur. They include stroke, heart attacks, and kidney damage. The more experienced the medical center in this procedure, the lower the risk.

Click the icon to see an image of cardiac catheterization.

Researchers are looking for biologic factors (called biomarkers) that will confirm a diagnosis or suggest a better or worse prognosis. Many are under investigation.

Tumor Necrosis Factor. Elevated levels of tumor necrosis factor (TNF) may be a very strong and accurate predictor of a poor outlook. This immune substance is known to be a potent substance in the inflammatory process.

Natriuretic Peptides. Natriuretic peptides are substances that help regulate salt and water balance in the body. Levels of these peptides increase as heart failure symptoms worsen. Blood tests for brain natriuretic peptide (BNP) are now used to help diagnose heart failure. There are two types of BNP tests: The enzyme-linked immunosorbent assay (ELISA) and the radioimmunosorbent assay (RIA). Research from 2006 suggested that the ELISA test may be more accurate, but it is also more expensive.

BNP testing can be very helpful in correctly diagnosing heart failure in patients who come to the emergency room complaining of shortness of breath (dyspnea). A 2006 study indicated that this test can also help predict which patients with dyspnea are at greatest risk of dying within a year from heart failure.

Brain Metabolites. High levels of a compound called N-acetylaspartate, generated as a byproduct of chemical processes in the brain, may indicate a poor outlook.

Treatment

Guidelines for evaluating the severity of heart failure and determining treatments use a staging system that is similar to the one used for major cancers:

Stage A: Patients are at high risk for heart failure, but there is no evidence of structural damage to the heart. Risk factors include high blood pressure, heart diseases, diabetes, obesity, metabolic syndrome, and previous use of medications that damage the heart (such as some chemotherapy).
Stage B: Patients have a structural heart abnormality but no symptoms of heart failure. Abnormalities include left ventricular hypertrophy and low ejection fraction, asymptomatic valvular heart disease, and a previous heart attack.
Stage C: Patients have a structural abnormality and current or previous symptoms of heart failure, including shortness of breath, fatigue, and difficulty exercising.
Stage D: Patients have end-stage symptoms that do not respond to standard treatments.

According to expert guidelines, the first step in managing heart failure is to treat the primary conditions causing or complicating heart failure. These include:

Coronary artery disease. Treatment includes a healthy diet, exercise, smoking cessation, medications, and, possibly, bypass or angioplasty. [See In-Depth Report #3: Coronary artery disease and angina.]
Cholesterol and lipid problems. Treatments include lifestyle management and medications, especially statins. [See In-Depth Report #23: Cholesterol.]
High blood pressure. A normal systolic blood pressure is considered below 120 mm Hg, and a normal diastolic blood pressure is below 80 mm Hg. Patients with diabetes or chronic kidney disease should maintain blood pressure readings of 130/80 or less, while other patients with high blood pressure should aim for readings no higher than 140/90. Effective reduction of blood pressure reduces the risk of heart failure by 30 - 50%. [See In-Depth Report #14: High blood pressure.]
Diabetes. Treating diabetes is extremely important for reducing the risk for heart disease. ACE inhibitors are especially beneficial, particularly for people with diabetes. Recent research suggests that metformin, a drug used to treat diabetes, may also help prevent heart failure. [See In-Depth Report #60: Diabetes - type 2; and In-Depth Report #9: Diabetes - type 1.]
Valvular abnormalities such as aortic stenosis and mitral regurgitation. Surgery may be required.
Abnormal health rhythms (arrhythmias). Ventricular assisted devices, notably biventricular pacers (BVPs), are proving to be important in preventing hospitalizations for patients with these conditions.
Anemia. Giving erythropoietin (EPO) and iron injections to patients with heart failure and underlying anemia not only reverses the anemia, but may markedly improve heart symptoms as well. [See In-Depth Report #57: Anemia.]
Thyroid function. Various medications are used to treat overactive thyroid (hyperthyroidism) or underactive thyroid (hypothyroidism). [See In-Depth Report #38: Hypothyroidism.]
Sleep apnea. Continuous positive airway pressure (CPAP) is an effective treatment for sleep apnea. CPAP may help reduce systolic blood pressure and improve left ventricular systolic function. [See In-Depth Report#65:Sleep apnea.]

Click the icon to see an image of CPAP treatment.

Treatments for patients with Stage B risk for heart failure include all of the treatments recommended in Stage A. In addition, the following types of drugs and devices may be recommended for some patients. These include:

Angiotensin-converting enzyme (ACE) inhibitors for patients with a recent or past history of heart attack. Also for patients who have not had a heart attack if they have a low left ventricular ejection fraction (LVEF) and no heart failure symptoms. A reduced LVEF indicates that the heart’s left ventricle is not pumping blood efficiently.
Beta blockers for patients with a recent or past history of heart attack. Also for patients who have not had a heart attack but who do have reduced LVEF without heart failure symptoms.
Angiotensin-receptor blockers (ARBs) for patients who have had a heart attack or have low LVEF, but who cannot take ACE inhibitors.
Implantable defibrillators for patients who have weakened heart pumps (ischemic cardiomyopathy), who had a heart attack more than 40 days prior, and who have low LVEF.

Treat conditions as recommended in Stage A plus:

Restrict dietary salt. Lowering salt in the diet can help diuretics work better.
ACE inhibitors, beta blockers, and diuretics are recommended for most patients.
ARBs are recommended for patients who cannot tolerate ACE inhibitors.
Aldosterone inhibitors or digitalis may be used for some patients.
A hydralazine and nitrate combination (BiDil) may be used for African-American patients who are taking an ACE inhibitor and beta blocker and who still have heart failure symptoms.
Avoid drugs that can worsen heart failure symptoms. These include nonsteroidal anti-inflammatory drugs (NSAIDs), most calcium channel blockers, and most drugs used to treat irregular heart rhythms (arrhythmia).
Exercise training for appropriate patients.
Biventricular pacemakers and implantable defibrillators for some patients.

Treatment includes appropriate measures used for Stages A, B, and C plus:

Heart transplantation referral for appropriate patients.
Left-ventricular assist devices (LVADs) as permanent therapy for patients who are not candidates for heart transplants. LVADs are surgically implanted to help pump blood through the body.
Hospice and end-of-life care information for patients and families.

Medications

Many different medications are used in the treatment of heart failure. They include:

Angiotensin-converting enzyme (ACE) inhibitors
Angiotensin-receptor blockers (ARBs)
Beta blockers
Diuretics
Aldosterone blockers
Digitalis
Hydralazine and nitrates
Statins
Nesiritide (Natrecor)
Aspirin

Angiotensin-converting enzyme (ACE) inhibitors are among the most important drugs for treating patients with heart failure. ACE inhibitors open blood vessels and decrease the workload of the heart. They are used to treat high blood pressure but can also help improve heart and lung muscle function. Major studies suggest that ACE inhibitors may reduce the risk of death, heart attack, and hospital admissions by 28% in patients with existing heart failure.

ACE inhibitors are particularly important for patients with diabetes. A large study reported that patients with diabetes who took these drugs had fewer heart attacks and lower overall mortality rates than patients who took other types of high blood pressure medications. ACE inhibitors may also help slow progression of kidney disease, in addition to controlling blood pressure.

Doctors sometimes avoid giving aspirin to patients who are taking ACE inhibitors due to concerns that this drug combination can cause kidney problems. A 2005 study of patients with both coronary artery disease and heart failure indicated that an aspirin and ACE inhibitor combination is not harmful, and that aspirin can significantly reduce mortality risk for these patients.

Choosing an ACE inhibitor. ACE inhibitors treat Stage A high-risk conditions such as high blood pressure, heart disease, and diabetic nerve disorders (neuropathy). They also treat Stage B patients who have had a heart attack or who have left ventricular systolic disorder, and Stage C patients with heart failure. Specific brands and stages include:

Benazepril (Lotrel) -- (Stage A)
Captopril (Capoten) -- (Stages A, B, C)
Enalapril (Vasotec) -- (Stages A, B, C)
Fosinopril (Monopril) -- (Stages A, C)
Lisinopril (Prinivil, Zestril) -- (Stages A, B, C)
Moexipril (Univasc) -- (Stage A)
Perindopril (Aceon) -- (Stage A)
Quinapril (Accupril) -- (Stages A, C)
Ramipril (Altace) -- (Stages A, B, C)
Trandolapril (Mavik) -- (Stages A, B, C)

Side Effects of ACE Inhibitors:

Low blood pressure is the main side effect of ACE inhibitors. This can be severe in some patients, especially at the start of therapy.
Irritating cough is a common side effect, which some people find intolerable. Although all ACE inhibitors can have this side effect, sometimes switching to another brand will reduce this symptom.
Although ACE inhibitors can protect against kidney disease, they also increase potassium retention in the kidneys. This increases the risk for cardiac arrest if potassium levels become too high. Because of this action, they are not generally given with potassium-sparing diuretics or potassium supplements.
A rare but severe side effect is granulocytopenia, which is an extreme reduction in infection-fighting white blood cells.
In very rare cases, patients suffer a sudden and severe allergic reaction called angioedema that causes swelling in the eyes and mouth and may close off the throat.

Patients who have difficulty tolerating ACE inhibitor side effects are usually switched to an angiotensin-receptor blocker (ARB).

ARBs, also known as angiotensin II receptor antagonists, are similar to ACE inhibitors in their ability to open blood vessels and lower blood pressure. They may have fewer or less-severe side effects than ACE inhibitors, especially coughing, and are sometimes prescribed as an alternative to ACE inhibitors. Some patients with heart failure take an ACE inhibitor along with an ARB.

Brands and Indications. ARBs are used to treat Stage A high-risk conditions such as high blood pressure and diabetic nerve disorders (neuropathy). They are also used to treat Stage B patients who have had a heart attack or who have left ventricular systolic disorder, and Stage C patients with heart failure. Specific brands, and the stage of heart failure they are used for, are listed below.

Candesartan (Atacand) -- (Stages A, C)
Eprosartan (Teveten) -- (Stage A)
Irbesartan (Avapro) -- (Stage A)
Losartan (Cozaar) -- (Stages A, B)
Olmesartan (Benicar) -- (Stage A)
Telmisartan (Micardis) -- (Stage A)
Valsartan (Diovan) -- (Stages A, B, C)

Common Side Effects

Low blood pressure
Dizziness and lightheadedness
Raised potassium levels
Drowsiness

Beta blockers are almost always used in combination with other drugs, such as ACE inhibitors and diuretics. They help slow heart rate and lower blood pressure. Research presented at the 2006 American College of Cardiology meeting indicated that beta-blockers are an important treatment for most patients with left ventricular heart failure. Data from the study found that the beta blocker carvedilol (Coreg) significantly lowered the risk of death or rehospitalization within 3 - 6 months after hospital discharge.

Beta blockers can help patients with heart failure by:

Treating high blood pressure, angina, arrhythmias, and preventing heart attack in high-risk patients.
Preventing left ventricular remodeling in patients with enlarged heart chambers and weakened heart muscles (dilated cardiomyopathy), and in those who have suffered a first heart attack.
Blocking inflammatory immune factors called cytokines, including tumor necrosis factor (TNF). TNF may play a key role in the process leading to heart failure.
Preventing norepinephrine (adrenaline) from binding to heart cells. Elevated levels of norepinephrine, a stress hormone, can overstimulate the failing heart and are associated with severe heart failure.

Brands and Indications. Beta blockers treat Stage A high blood pressure. They are also treat Stage B patients (both those who have had a heart attack and those who have not had a heart attack but who have heart damage). Recent guidelines identify three drugs best for treating Stage C patients with heart failure. Specific brands and stages include:

Acebutolol (Sectral) -- (Stage A)
Atenolol (Tenormin) -- (Stages A, B)
Betaxolol (Kerlone) -- (Stage A)
Bisoprolol (Zebeta) -- (Stages A, C)
Cartelol (Cartrol) -- (Stage A)
Carvedilol (Coreg) -- (Stages A, B, C)
Labetalol (Trandate) -- (Stage A)
Metoprolol succinate (Toprol XL) -- (Stages A, C)
Metoprolol tartrate (Lopressor) -- (Stages A, B)
Nadolol (Corgard) -- (Stage A)
Penbutolol (Levatol) -- (Stage A)
Pindolol (Visken) -- (Stage A)
Propranolol (Inderal) -- (Stages A, B)
Timolol (Blocadren, Timolide) -- (Stages A, B)

Beta Blocker Concerns

Do not abruptly stop taking these drugs. The sudden withdrawal of beta blockers can rapidly increase heart rate and blood pressure. Your doctor may want you to slowly decrease the dose before stopping completely.
Beta blockers are categorized as non-selective or selective. Non-selective beta blockers such as carvedilol and propranolol can narrow bronchial airways. Patients with asthma, emphysema, or chronic bronchitis should not use these beta blockers.
Beta blockers can lower HDL (“good”) cholesterol.
These drugs can hide warning signs of low blood sugar (hypoglycemia) in patients with diabetes.
Beta blockers are usually used in combination with ACE inhibitors, but the two drugs are not started at the same time. Research presented at the 2005 European Society of Cardiology meeting indicates that either a beta blocker or an ACE inhibitor can be prescribed at first, and the other drug added on later.

Common Side Effects

Fatigue and lethargy
Vivid dreams and nightmares
Depression
Memory loss
Dizziness and lightheadedness
Reduced ability to exercise
Coldness in extremities (legs, toes, arms, hands)

Check with your doctor about any side effects. Do not stop taking these drugs on your own.

Diuretics cause the kidneys to rid the body of excess salt and water. Fluid retention is a major symptom of heart failure. Aggressive use of diuretics can help eliminate excess body fluids, while reducing hospitalizations and improving exercise capacity. These drugs are also important to help prevent heart failure in patients with high blood pressure. In addition, certain diuretics, notably spironolactone (Aldactone), block aldosterone, a hormone involved in heart failure. This drug class is beneficial for patients in late stages of heart failure (Stages C and D).

Diuretic Types and Brands. Diuretics come in many brands and are generally inexpensive. Some need to be taken once a day, some twice a day. Treatment is usually started at a low dose and gradually increased. Diuretics are virtually always used in combination with other drugs, especially ACE inhibitors and beta blockers. There are three main types of diuretics:

Potassium-sparing diuretics. These include amiloride (Midamor), spironolactone (Aldactone), and triamterene (Dyrenium).
Thiazide diuretics. These include chlorothiazide (Diuril), chlorthalidone (Hygroton), indapamide (Lozol), hydrochlorothiazide (Esidrix, HydroDiuril), and metolazone (Mykrox, Zaroxolyn).
Loop diuretics. Because loop diuretics act faster than other diuretics it is important to avoid dehydration and potassium loss. Loop diuretics include bumentanide (Bumex), furosemide (Lasix), and torsemide (Demadex).

Problems with Diuretics. Loop and thiazide diuretics deplete the body's supply of potassium, which, if left untreated, increases the risk for arrhythmias. Arrhythmias are heart rhythm disturbances that can, in rare instances, lead to cardiac arrest. In such cases, doctors will prescribe lower doses of the current diuretic, recommend potassium supplements, or use potassium-sparing diuretics either alone or in combination with a thiazide. Potassium-sparing drugs have their own risks, which include dangerously high levels of potassium in people with existing elevated levels of potassium or in those with damaged kidneys. However, all diuretics are generally more beneficial than harmful.

Common Side Effects

Fatigue
Depression and irritability
Urinary incontinence
Reduced sexual drive

Aldosterone is a hormone that is critical in controlling the body's balance of salt and water. Excessive levels may play important roles in hypertension and heart failure. Drugs that block aldosterone are prescribed for some patients with Stage C heart failure.

Spironolactone (Aldactone, Spirinol) is both a potassium-sparing diuretic and an aldosterone blocker. A major study of patients with heart failure found that spironolactone reduced death rate by 30%. Like all medications for heart failure, it must be used with care; elevated potassium levels are a potential risk of therapy.
Eplerenone (Inspra), a newer aldosterone blocker, has been specifically approved for treatment of heart failure. It is prescribed for patients who have heart failure following a heart attack. Its actions are similar to potassium-sparing diuretics and, like these drugs, it poses some risk for high potassium levels.

Digitalis is derived from the foxglove plant. It has been used to treat heart disease since the 1700s. Digoxin (Lanoxin) is the most commonly prescribed digitalis preparation. Digoxin decreases heart size and reduces certain heart rhythm disturbances (arrhythmias).

Unfortunately, digitalis does not reduce mortality rates, although it does reduce hospitalizations and worsening of heart failure. Controversy has been ongoing for more than 100 years over whether the benefits of digitalis outweigh its risks and adverse effects.

Digitalis may be useful for patients with left-ventricular systolic dysfunction who do not respond to other drugs (diuretics, ACE inhibitors). It is also used for patients who have atrial fibrillation.

Digitalis does not appear to help patients with left-ventricular diastolic heart failure. It may be harmful in patients with right-ventricular heart failure and those who stop taking digoxin after using it in combination with ACE inhibitors.

Side Effects and Problems. While digitalis is generally a safe drug, it can have toxic side effects due to overdose or other accompanying conditions. The most serious side effects are arrhythmias (abnormal heart rhythms that can be life-threatening). Early signs of toxicity may be irregular heartbeat, nausea and vomiting, stomach pain, fatigue, visual disturbances (such as yellow vision, seeing halos around lights, flickering or flashing of lights), and emotional and mental disturbances.

Many factors increase the chance for side effects.

Advanced age
Low blood potassium levels (which may be caused by diuretics)
Hypothyroidism
Anemia
Valvular heart disease
Impaired kidney function

Digitalis also interacts with many other drugs, including quinidine, amiodarone, verapamil, flecainide, amiloride, and propafenone.

A blood test that monitors drug levels in patients taking the drug can limit the rate of toxicity to about 2%. For most patients with mild-to-moderate heart failure, low-dose digoxin may be as effective as higher doses. If side effects are mild, patients should still consider continuing with digitalis if they experience other benefits.

Hydralazine and nitrates are two older drugs that help relax arteries and veins, thereby reducing the heart's workload and allowing more blood to reach the tissues. In 2005, the FDA approved BiDil, a drug that combines isosorbide dinitrate and hydralazine. BiDil is approved to specifically treat heart failure in African-Americans. African-Americans have a particularly high risk for heart failure. BiDil is the first drug approved for a specific racial group. The Food and Drug Administration (FDA) based its approval on a landmark 2004 study published in the New England Journal of Medicine, which showed that African-Americans who took the drug were 43% more likely to survive heart failure than patients who took placebo. Some experts suggest that BiDil could also benefit other racial groups.

Statins are important drugs used to lower cholesterol and to prevent heart disease leading to heart failure. These drugs include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). In 2007, the FDA approved atorvastatin to reduce the risks for hospitalization for heart failure in patients with heart disease.

In a 2006 Journal of the American Medical Association study, patients with heart failure who began taking a statin drug had a 24% lower relative risk of death and a 21% lower relative risk of hospitalization for heart failure than patient who did not take a statin. Statins appeared to help these patients regardless of whether or not they had co-existing coronary heart disease.

Aspirin is a type of non-steroid anti-inflammatory (NSAID). A 2005 study in the Journal of the American College of Cardiology indicated that aspirin is important for preventing heart failure death in patients with heart disease, and can safely be used with ACE inhibitors. However, some research has suggested that NSAIDs may increase the risk of heart failure for patients with a history of heart disease, especially when used in combination with ACE inhibitors or diuretics. Patients with heart disease should ask their doctor which NSAIDs are right for them.

Nesiritide treats patients who have arrived at a hospital with decompensated heart failure. Decompensated heart failure is a life-threatening condition in which the heart fails over the course of minutes or a few days, often as the result of a heart attack or sudden and severe heart valve problems. However, nesiritide may cause serious kidney damage.

In 2005, the FDA released recommendations from an expert panel concerning the appropriate and inappropriate use of nesiritide. The panel emphasized that nesiritide should be used to treat only patients with decompensated heart failure who have shortness of breath (dyspnea) and trouble breathing. The drug should not be a replacement for diuretics.

Despite these warnings, some doctors have prescribed nesiritide “off-label” to treat patients with severe heart failure outside of a hospital setting. Research presented at the 2007 American College of Cardiology annual conference criticized this practice by demonstrating that nesiritide plus standard treatment does not reduce the risk of heart- or kidney-related death or hospitalization. In addition, the research suggested some concerns about nesiritide’s overall safety.

Tolvaptan. Tolvaptan is an investigational drug that is being studied in combination with standard therapy for treatment of heart failure. It is especially being investigated for acute decompensated heart failure, a type of heart failure categorized by fluid build-up in the lungs (pulmonary edema) for which there are few available treatments. In patients hospitalized with heart failure, tolvaptan plus standard drugs improved breathing problems (dyspnea) and reduced fluid accumulation (edema) and body weight, according to two studies published in 2007 in the Journal of the American Medical Association. However, the drug did not appear to reduce the risk of re-hospitalization or death.

Levosimendan. Levosimendan is an experimental inotropic drug that is being investigated as a treatment for severely ill patients with heart failure. It belongs to a new class of drugs called calcium sensitizers that may help improve heart contractions and blood flow. Clinical trials suggest that levosimendan may improve survival in patients hospitalized for heart failure. The drug also appears to reduce levels of BNP (brain natriuretic peptide), a chemical marker for heart failure severity.

Prograf. Tacrolimus (Prograf) was approved in 2006 to help prevent organ rejection in patients who have received a heart transplant. The drug suppresses the immune system. Patients who receive this drug are at increased risk of developing lymphoma (a cancer of the immune system).

Surgery and Devices

Revascularization surgery helps to restore blood flow to the heart. It can treat blocked arteries in patients with coronary artery disease and may help selected patients with heart failure. Surgery types include coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI). CABG is a traditional type of open heart surgery. PCI, also called angioplasty, uses a catheter to inflate a balloon inside the artery. A metal stent may also be inserted during a PCI procedure. [See In-Depth Report#03:Coronary artery disease.]

A 2006 study suggested that early treatment with revascularization surgery may be particularly important for patients with systolic heart failure, a condition that occurs when the heart does not pump out enough blood. This condition has a very high death rate. Researchers found that CABG or PCI surgery halved the risk of dying compared to standard drug therapy. Patients in the study first underwent a positron emission tomography (PET) test to determine if they would be good candidates for surgery.

Click the icon to see an illustrated series detailing coronary artery balloon angioplasty.

Click the icon to see an illustrated series detailing heart bypass surgery.

In appropriate patients, mitral valve surgery may significantly reduce the severity of heart failure. In a study of 92 patients with late-stage heart failure and faulty valves, reconstruction of the heart's mitral valve drastically improved heart function.

An experimental mesh "heart sock" is being investigated as an adjunct to mitral valve repair surgery. Research presented at the 2004 American Heart Association Scientific Sessions suggested that the device reduced the progression of heart failure and halved the need for transplant surgery. The "sock" helps realign the shape of the heart and improve heart function. To date, it has been tested in patients with dilated cardiomyopathy.

Ventricular Remodeling. Ventricular remodeling (also called partial left ventriculectomy or the Batista procedure, after its inventor) may allow some patients with dilated cardiomyopathy to avoid a heart transplant.

The procedure involves the following:

The surgeon first performs ventriculectomy, which is the removal of a section of healthy heart muscle weighing about 3 ounces.
The surgeon then reshapes the heart to a more normal size and form.
Any faulty heart valves are repaired.

Ventricular remodeling is still relatively new, and mortality rates are very high. Studies on long-term improvement are mixed. More research is needed to target the patients who would most benefit.

Patients who suffer from severe heart failure and whose symptoms do not improve with drug therapy or mechanical assistance may be candidates for heart transplantation. Some 3,600 people are awaiting a transplant, although only about 2,000 operations are performed each year.

The most important factor for heart transplant eligibility is overall health. Chronological age is less important. Most heart transplant candidates are between the ages of 50 – 64 years. About 72% of transplant patients are male, and 70% are white.

While the risks of this procedure are high, the 1-year survival rate is about 86% for men and 84% for women. The 3-year survival rate is 78% for men and 75% for women. Five years after a heart transplant, about 71% of men and 67% of women remain alive. In general, the highest risk factors for death 3 or more years after a transplant operation are coronary artery disease and the adverse effects (infection and certain cancers) of immunosuppressive drugs used in the procedure. The rejection rates in older people appear to be similar to those of younger patients.

In 2004, the FDA approved a temporary artificial heart (Syncardia) intended to keep patients alive in the hospital while they waited for a heart transplant. In 2006, the FDA approved the first permanent implantable artificial heart (AbiCor). The AbiCor is available only for patients who are not eligible for a heart transplant and who are not expected to live more than a month without medical treatment. The device requires a large chest cavity, which means that most women will not be eligible for it. Of the 14 men who have received the AbiCor, the average survival was less than 5 months after surgery. Only one patient was discharged from the hospital. The device’s manufacturer is working on a new model that it hopes will extend survival by as long as 5 years.

A growing array of heart devices and machines are changing the face of heart failure treatment. They have gained widespread acceptance for use as a bridge to transplant in patients who are on medications but still have severe symptoms and are awaiting a donor heart. Increasingly, though, doctors are exploring the possibility that such devices may be satisfactory treatments themselves, forestalling the need for a transplant altogether in some patients.

Ventricular Assist Devices (VADs). Ventricular assist devices are machines that help improve pumping actions. Several models with slightly different features are in use or under investigation. Some include the following:

Left ventricular assist device (LVAD) are used for patients whose heartbeat has slowed dangerously (a condition called bradycardia) to help take over the pumping action of the failing heart. Studies suggest that in some people the use of an LVAD may allow some of the damaged heart muscle to heal, perhaps even helping some patients avoid heart transplants. These devices are also being studied in combination with drug therapy to help recover heart function and improve patients’ chances for survival. Until recently, these machines required remaining in the hospital. Smaller battery-powered LVAD units, however, are allowing many patients to leave the hospital and are proving to be effective bridges to heart transplants in adults. The HeartMate, for example, a portable LVAD about the size of a portable CD player (2 in. by 4 in.), is implanted in the upper abdomen. The implanted device plugs into an external power base, which is used when the patient is at rest to recharge the battery and provide continuous power.
Fully implanted miniature artificial pumps that assist the heart (not replace it) are also being tested. The DeBakey ventricular assist device (VAD) for example, is a tiny heart pump that weighs less than 4 ounces. It has been approved in Europe and is being tested in the United States. The Jarvik 2000 heart pump is also showing promise.
The intra-aortic balloon pump (IABP) is helpful for maintaining heart function in people with left-side failure waiting for transplants and in those who develop a sudden and severe deterioration of heart function. The IABP is an implanted thin balloon that is usually inserted into the artery in the leg and threaded up to the aorta leading from the heart. Its pumping action is generated by inflating and deflating the balloon at certain rates. Usually, it is used only for short periods, but some studies indicate that patients may be able to use it safely for somewhat longer periods (an average duration of 23 days in one study).

There are risks involved with many of these devices, including bleeding, blood clots, and right-side heart failure. Infections are a particular hazard.

Pacers (Pacemakers). Pacers, or pacemakers, help regulate the heart’s beating action, especially when the heart beats too slowly. Biventricular pacers (BVPs) are a special type of pacemaker used for patients with heart failure. Because BVPs help the heart’s left and right chambers beat together, this treatment is called cardiac resynchronization therapy (CST). BVPs may particularly help heart failure patients who have left bundle branch block, a condition in which the electrical impulses in the heart do not follow their normal pattern. In general, BVPs are recommended for patients with moderate-to-severe heart failure. A small 2006 study suggested that a defibrillator may be better suited for patients with moderate heart failure, while indicating a BVP might be best for patients with severe heart failure.

Implantable Cardioverter-Defibrillators. Devices called implantable cardioverter-defibrillators (ICDs), which are sometimes combined with pacemakers, work well for preventing arrhythmias (abnormal heart rhythms) in heart failure patients. Studies have also found them effective in preventing sudden death from severe rhythm disturbances in patients with weakened hearts from previous arrhythmias and in patients with genetic hypertrophic cardiomyopathy. Patients who have an ICD should avoid taking fish oil supplements. A 2005 Journal of the American Medical Association study found that omega-3 fatty acid supplements may increase the risk of rapid heart beat (ventricular tachycardia) or irregular heart rhythm (ventricular fibrillation) in some of these patients.

ICDs have many benefits, and recent expert guidelines recommend that they be used in more patients with heart failure. However, in June 2005, certain ICD models and biventricular pacemaker-defibrillators were recalled by the manufacturer because of a circuitry flaw that prevents the devices from delivering therapeutic electrical shocks when needed. The problem may result in patient death. Although the FDA did not make any specific recommendations, the agency encourages patients who may have such a device to ask their doctor if they should have it removed or replaced.

In April 2006, two studies published in the Journal of the American Medical Association evaluated data concerning the safety and reliability of implantable pacemakers and defibrillators. The studies found that from 1990 – 2002, pacemakers became increasingly reliable. From 1998 – 2002, ICDs had a significantly higher rate of malfunction than pacemakers, although the reliability of ICDs appeared to improve from 2003 – 2004.

In October 2006, the U.S. Heart Rhythm Society issued recommendations for doctors, manufacturers, and the FDA to help improve communication concerning performance and recalls of ICDs and pacemakers. Experts stress that the chance of an ICD or pacemaker saving a person’s life far outweigh the possible risks of these devices failing.

Ultrafiltration devices are used in hospitals to pump excess water and salt from the body. Catheters are inserted into several of the patient’s veins. The catheters are connected to a blood filter device. Blood is withdrawn through one of the catheters and filtered in the device to remove excess fluid. The filtered blood is then returned to the patient through another catheter. A 2006 study reported that ultrafiltration devices may work better than diuretic drugs for patients with acute decompensated heart failure (ADHF). ADHF is heart failure that has rapidly deteriorated so that patients require immediate hospitalization.

Lifestyle Changes

Between 30 - 47% of patients who require hospitalization for heart failure are back in the hospital within 6 months. Many people return because of lifestyle factors such as poor diet, failure to comply with medications, and social isolation.

In one study, elderly people who had no emotional support at home had triple the risk of a heart attack after hospitalization for heart failure than those who did have such support. (Women had eight times the risk.) In another study, the greatest risk factor for death and readmission to the hospital after a first hospitalization was being single, regardless of the health of the patient at discharge. A third study confirmed that a strong marriage predicted long-term survival. Evidence continues to mount that programs that offer intensive follow-up to ensure that the patient complies with lifestyle changes and medication regimens at home are reducing rehospitalization rates and improving survival. Patients without available rehabilitation programs should seek support from local and national heart associations and groups.

Patients should weigh themselves each morning and keep a record. Any changes are important:

A sudden increase in weight of more than 2 - 3 pounds may indicate fluid accumulation and should prompt an immediate call to the doctor.
Rapid wasting weight loss over a few months is a very serious sign and may indicate the need for surgical intervention.

Whole Grains. Evidence suggests that daily consumption of whole grain foods may help prevent heart failure. In research presented at a 2007 American Heart Association conference, people who ate whole-grain breakfast cereals seven or more times a week had a 28% lower risk of developing heart failure than those who never ate these cereals.

Mediterranean Diet. Evidence suggests that the Mediterranean diet helps protect the heart and may even reduce the risk for heart failure after a first heart attack. The diet emphasizes whole grains, fish, olive oil, garlic, and moderate daily intake of wine. There are several variations to the Mediterranean diet but general recommendations include:

Limit red meats.
Limit dairy products.
Eat moderate amounts of fish and poultry. Fish is the diet’s main protein source. Some studies suggest that fish is the primary heart-protective ingredient in this diet. However, patients who have an implantable defibrillator should not take fish oil supplements. A 2005 study suggested that these supplements may worsen heart rhythm problems in some patients.
Eat plenty of fresh fruits and vegetables, nuts, legumes, beans, and whole grains.
Daily glass or two of wine. Light-to-moderate alcohol use may reduce the risk for heart failure, (but heavy alcohol consumption is a risk factor).
Plenty of fresh fruits and vegetables, as well as nuts, legumes, beans, and whole grains.

DASH Diet. The Dietary Approaches to Stop Hypertension (DASH) diet is an important lifestyle step in managing blood pressure. It may also be useful for many patients with heart failure. This diet is not only rich in important nutrients and fiber but also includes foods that contain two and a half times the amounts of electrolytes, potassium, calcium, and magnesium found in the average American diet.

Potassium-rich foods, which are important for patients with heart failure, include bananas, oranges, prunes, cantaloupes, carrots, spinach, celery, alfalfa, mushrooms, lima beans, potatoes, avocados, and broccoli. However, patients who take potassium-sparing diuretics or ACE inhibitors, and those with kidney dysfunction, may have to restrict their potassium intake.

The DASH diet is rich in whole grains and fresh fruits and vegetables. It stresses avoiding saturated fats, as any healthy diet does, although it includes calcium-rich dairy products that are non- or low-fat. When choosing fats, the diet recommends monounsaturated oils such as olive or canola oil.

Salt Restriction. People with high blood pressure are generally urged to restrict salt, although certain people may be more susceptible to its effects. For example, a high intake of salt may be an independent risk factor for the development of heart failure in people who are overweight. All patients with heart failure should limit their salt intake, and in severe cases, very stringent salt restriction may be necessary. Patients should not add salt to their cooking and their meals. They should also avoid foods high in sodium. These salty foods include ham, bacon, hot dogs, lunch meats, prepared snack foods, dry cereal, cheese, canned soups, soy sauce, and condiments. Some patients may need to reduce their water intake as well. People with high cholesterol levels or diabetes require additional dietary precautions. [See In-Depth Report #43: Heart-healthy diet. ]

People with heart failure used to be discouraged from exercising. Now, experts think that exercise, when performed under medical supervision, is extremely important for many patients with stable conditions. Studies have reported that patients with stable conditions who engage in regular moderate exercise (three times a week) experience a better quality of life and lower mortality rates than those who do not exercise.

The following guidelines are critical:

Experts warn that exercise is not appropriate for all patients with heart failure. If you have heart failure, always consult your doctor before starting an exercise program.
People who are approved for, but not used to, exercise should start with 5 - 15 minutes of easy exercise with frequent breaks. Although the goal is to build up to 30 - 45 minutes of walking, swimming, or low-impact aerobic exercises three to five times every week, even shorter times spent exercising are useful.

Studies report benefits from specific exercises:

Progressive strength training may be particularly useful for patients with heart failure since it strengthens muscles, which commonly deteriorate in this disorder. Strength training typically uses light weights, weight machines, or even the body's weight (leg raises or sit-ups, for example). Even performing daily handgrip exercises can improve blood flow through the arteries.
Patients who exercise regularly using supervised treadmill and stationary-bicycle exercises can increase their exercise capacity by 14 - 36%. In one study, patients as old as 91 years increased their oxygen consumption significantly after 6 months of supervised treadmill and stationary bicycle exercises. Exercising the legs may help correct problems in heart muscles. In one study, patients who did leg extension exercises for 8 weeks had higher levels of an enzyme involved in forming new blood vessels. Exercise has also been associated with reduced inflammation in blood vessels.
Dancing may be a fun and beneficial alternative to standard aerobic exercise, according to research presented at the 2006 annual meeting of the American Heart Association. In a study of patients with stable chronic heart failure, dancing helped improve cardiopulmonary fitness, arterial elasticity, and quality of life. Patients in the study danced fast and slow waltzes for 21 minutes, three times a week.

Bed rest may be required in cases of severe heart failure. To reduce congestion in the lungs, the patient's upper body should be elevated. For most patients, resting in an armchair is better than lying in bed. Relaxing and contracting leg muscles is important to prevent clots. As the patient improves, a doctor will progressively recommend more activity.

Experts have traditionally recommended that people with heart failure avoid warm baths, which can increase the heart rate. Some studies now report that carefully controlled bathing for short periods may not be harmful and may actually be beneficial, reducing irregular heart beats and increasing cardiac output and ejection fraction. Warm water may behave like a vasodilating drug, opening up the vessels gently and improving circulation. In clinical trials, patients sat in warm water or a dry sauna for 10 minutes, with their bodies tilted at a 45 degree angle.

Warning Note: Prolonged periods in hot or even warm conditions can be dangerous. Any patient with heart failure should consult their doctor first, not bathe unaccompanied, and be sure that the temperature does not go above 106° Fahrenheit for water bathing or 140° Fahrenheit for dry saunas.

Stress reduction techniques, such as meditation and relaxation response methods, may have direct physical benefits for lowering stress hormones. These hormones include cortisol, which suppresses the immune system, and norepinephrine (also known as adrenaline), the chemical messenger associated with heart dysfunction.

Patients with heart failure may resort to alternative remedies. Such remedies are often ineffective and may have severe or toxic effects. Of particular note for patients with heart failure is an interaction between St. John's wort (an herbal medicine used for depression) and digoxin (a heart drug). St. John's wort can significantly interfere with this drug.

Arginine. Some evidence suggests that arginine (also called L-arginine) may have some benefit. This amino acid appears to reduce endothelin, a protein that causes blood vessel constriction and is found in high amounts in patients with heart failure. It can have adverse effects, however, including gastrointestinal problems. It can also lower blood pressure and change levels of certain chemicals and electrolytes in the body. It may increase the risk for bleeding. Some people have an allergic reaction to it, which in same cases may be severe. It may worsen asthma.

Coenzyme Q10 and Vitamin E. Small studies have suggested that coenzyme Q10 (CoQ10) may help patients with heart failure, particularly when combined with vitamin E. CoQ10 is a vitamin-like substance found in organ meats and soybean oil. More recent studies, however, have found that CoQ10 and vitamin E do not help the heart or prevent heart disease. According to a 2005 Journal of the American Medical Association study, vitamin E supplements can actually increase the risk of heart failure, especially for patients with diabetes or vascular diseases.

Crataegus Extract. An herbal remedy, Crataegus Extract WS1442, which is made from the leaves of the Crataegus tree, may have antioxidant properties that can help patients with heart failure. In a study presented at the 2007 American College of Cardiology annual meeting, over 2,000 patients with severe heart failure were randomized to receive either Crataegus Extract or placebo (plus standard drug treatment) for 2 years. The researchers noted a 20% reduction in heart-related deaths among patients who received the extract, and suggested that the herb extended patients’ lives by 4 months during the first 18 months of the study.

Other Vitamins and Supplements. A wide variety of other vitamins (thiamin, B6, and C), minerals (calcium, magnesium, zinc, manganese, copper, selenium), nutritional supplements (carnitine, creatine), and herbal remedies (hawthorn) have been proposed as treatments for heart failure. None have been adequately tested. There is no evidence that a particular vitamin or supplement can cure heart failure. In any case, vitamins are best consumed through the food sources contained in a healthy diet.

Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been several reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.

Resources

www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.americanheart.org -- American Heart Association
www.acc.org -- American College of Cardiology
www.hfsa.org -- Heart Failure Society of America
www.heartfailure.org -- Heart Failure Online
www.unos.org -- United Network for Organ Sharing
www.organdonor.org -- National Transplant Society
www.organdonor.gov -- US government organ donor site

References

Ahmed A, Rich MW, Fleg JL, Zile MR, Young JB, Kitzman DW, et al. Effects of digoxin on morbidity and mortality in diastolic heart failure: the ancillary digitalis investigation group trial. Circulation. 2006 Aug 1;114(5):397-403.

Battaglia M, Pewsner D, Juni P, Egger M, Bucher HC, Bachmann LM. Accuracy of B-type natriuretic peptide tests to exclude congestive heart failure: systematic review of test accuracy studies. Arch Intern Med. 2006 May 22;166(10):1073-80.

Bhatia RS, Tu JV, Lee DS, Austin PC, Fang J, Haouzi A, et al. Outcome of heart failure with preserved ejection fraction in a population-based study. N Engl J Med. 2006 Jul 20;355(3):260-9.

Birks EJ, Tansley PD, Hardy J, George RS, Bowles CT, Burke M, et al. Left ventricular assist device and drug therapy for the reversal of heart failure. N Engl J Med. 2006 Nov 2;355(18):1873-84.

Bryson CL, Mukamal KJ, Mittleman MA, Fried LP, Hirsch CH, Kitzman DW, et al. The association of alcohol consumption and incident heart failure: the Cardiovascular Health Study. J Am Coll Cardiol. 2006 Jul 18;48(2):305-11.

Bursi F, Weston SA, Redfield MM, Jacobsen SJ, Pakhomov S, Nkomo VT, et al. Systolic and diastolic heart failure in the community. JAMA. 2006 Nov 8;296(18):2209-16.

Carlson MD, Wilkoff BL, Maisel WH, Carlson MD, Ellenbogen KA, Saxon LA, et al. Recommendations from the Heart Rhythm Society Task Force on Device Performance Policies and Guidelines Endorsed by the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) and the International Coalition of Pacing and Electrophysiology Organizations (COPE). Heart Rhythm. 2006 Oct;3(10):1250-73.

Davis BR, Piller LB, Cutler JA, Furberg C, Dunn K, Franklin S, et al. Role of diuretics in the prevention of heart failure: the Antihypertensive andLipid-Lowering Treatment to Prevent Heart Attack Trial. Circulation. 2006 May 9;113(18):2201-10. Epub 2006 May 1.

Gheorghiade M, Abraham WT, Albert NM, Greenberg BH, O'Connor CM, She L, et al. Systolic blood pressure at admission, clinical characteristics, and outcomes inpatients hospitalized with acute heart failure. JAMA. 2006 Nov 8;296(18):2217-26.

Gheorghiade M, Konstam MA, Burnett JC Jr, Grinfeld L, Maggioni AP, Swedberg K, et al. Short-term clinical effects of tolvaptan, an oral vasopressin antagonist, in patients hospitalized for heartfFailure: the EVEREST clinical status trials. JAMA. 2007 Mar 25; [Epub ahead of print]

Go AS, Lee WY, Yang J, Lo JC, Gurwitz JH. Statin therapy and risks for death and hospitalization in chronic heart failure. JAMA. 2006 Nov 1;296(17):2105-11.

Hildebrandt P. Systolic and nonsystolic heart failure: equally serious threats. JAMA. 2006 Nov 8;296(18):2259-60.

Konstam MA, Gheorghiade M, Burnett JC Jr, Grinfeld L, Maggioni AP, Swedberg K, et al. Effects of oral tolvaptan in patients hospitalized for worsening heart failure: the EVEREST Outcome Trial. JAMA. 2007 Mar 25; [Epub ahead of print]

Lee DS, Pencina MJ, Benjamin EJ, Wang TJ, Levy D, O'Donnell CJ, et al. Association of parental heart failure with risk of heart failure in offspring. N Engl J Med. 2006 Jul 13;355(2):138-47.Maisel WH. Pacemaker and ICD generator reliability: meta-analysis of device registries. JAMA. 2006 Apr 26;295(16):1929-34.

Maisel WH, Moynahan M, Zuckerman BD, Gross TP, Tovar OH, Tillman DB, et al. Pacemaker and ICD generator malfunctions: analysis of Food and Drug Administration annual reports. JAMA. 2006 Apr 26;295(16):1901-6.

Mueller C, Laule-Kilian K, Schindler C, Klima T, Frana B, Rodriguez D, et al. Cost-effectiveness of B-type natriuretic peptide testing in patients with acute dyspnea. Arch Intern Med. 2006 May 22;166(10):1081-7.

Owan TE, Hodge DO, Herges RM, Jacobsen SJ, Roger VL, Redfield MM. Trends in prevalence and outcome of heart failure with preserved ejection fraction. N Engl J Med. 2006 Jul 20;355(3):251-9.

Review Date:
4/11/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

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adam.com

Coronary artery disease

FitSugar — Wed, 08 Oct 2008 17:35:07 -0700

In This Report

Highlights
Introduction
Prognosis
Risk Factors
Diagnosis
Managing Heart Disease
Anti-Clotting Medications...
Other Medications
Surgery
Coronary Artery Bypass Graf...
Angioplasty and Stents
Other Treatments
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Angioplasty Versus Drugs

Angioplasty works no better than drug therapy (high blood pressure, cholesterol, anti-platelet, and other medication) in preventing heart attack and stroke in patients with stable coronary artery disease (CAD), according to an important New England Journal of Medicine study. Experts still recommend angioplasty for patients with unstable or severe CAD.

Stents

Stents coated with drugs may have a slightly higher risk of causing blood clots than bare metal stents, according to FDA meetings held in late 2006. Researchers still need to conduct more research before reaching final conclusions.
Drug-coated stents work well when they are used for patients with specific types of heart conditions, indicate several studies published in the New England Journal of Medicine. However, problems may develop when these stents are used for “off-label” purposes. Experts are also concerned that both bare metal and drug-coated stents may be used too frequently.
Patients who receive a drug-coated stent must take both aspirin and an anti-platelet thienopyridine drug (usually clopidogrel) for at least 1 year after the stent is inserted, advises an important statement from the American Heart Association. Patients who cannot take a thienopyridine drug should receive a bare metal stent instead of a drug-coated stent.

Anti-Bleeding Drugs for Coronary Artery Bypass Graft (CAGB)

Aprotinin (Trasylol), a drug used to control bleeding during CABG, is more dangerous than other types of anti-bleeding drugs, according to a 2007 study in the Journal of the American Medical Association. Many experts now recommend against its use.

Diagnosis

Blood tests for biomarkers do not provide much more predictive information than standard disease risk factors, suggest several recent studies. In a 2006 study published in the New England Journal of Medicine, researchers found that risk factors such as high blood pressure, high cholesterol, and diabetes are still the best methods for predicting the likelihood of heart disease and heart-related death.

Introduction

In order to perform the difficult task of pumping blood to the rest of the body, the heart muscle itself needs a plentiful supply of oxygen-rich blood, which is provided through a network of coronary arteries. These arteries carry oxygen-rich blood to the heart's muscular walls (the myocardium).

Click the icon to see an image of the anterior heart arteries.

If blood flow to the myocardium is interrupted, an injury known as an infarct occurs. This is also known as myocardial infarction or, more commonly, a heart attack.

Click the icon to see an animation about coronary artery disease.

Coronary artery disease is the end result of a complex process called atherosclerosis (commonly called "hardening of the arteries"). This causes blockage of arteries (ischemia ) and prevents oxygen-rich blood from reaching the heart. There are many steps in the process leading to atherosclerosis, some not fully understood.

Click the icon to see an image of atherosclerosis.

Increasingly, however, researchers are studying the interactions between cholesterol and processes known as oxidation and the inflammatory response.

Cholesterol and Lipoproteins. The story begins with cholesterol and sphere-shaped bodies called lipoproteins that transport cholesterol.

Cholesterol is a white, crystalline substance that is found in all animal cells and in animal-based foods. It is critical for many functions, but under certain conditions cholesterol can have harmful effects.
The lipoproteins that transport cholesterol are referred to by their size. The most commonly known are low-density lipoproteins (LDL) and high density lipoproteins (HDL). LDL is often referred to as the "bad" cholesterol and HDL as the "good" cholesterol.

Click the icon to see an image of cholesterol inside an artery.

Oxidation. The damaging process called oxidation is an important trigger in the atherosclerosis story.

Oxidation is a chemical process in the body caused by the release of unstable particles known as oxygen-free radicals. It is one of the normal processes in the body, but under certain conditions (such as exposure to cigarette smoke or other environment stresses) these free radicals are overproduced.
In excess amounts, they can be very dangerous, causing damaging inflammation and even affecting genetic material in cells.
In heart disease, free radicals are released in artery linings and oxidize low-density lipoproteins (LDL). The oxidized LDL is the basis for cholesterol build-up on the artery walls and damage leading to heart disease.

Inflammatory Response. For the arteries to harden there must be a persistent reaction in the body that causes ongoing harm. Researchers now believe that this reaction is an immune process known as the inflammatory response. The following is one theory about how the inflammatory response contributes to heart disease:

The injuries to the arteries during oxidation signal the immune system to release white blood cells (particularly those called neutrophils and macrophages) at the site. These factors initiate the inflammatory response.
Macrophages literally "eat" foreign debris, in this case oxidized LDL cholesterol.
The process converts LDL cholesterol into foamy material that attaches to the smooth muscle cells of the arteries. The cholesterol becomes mushy and accumulates on artery walls.
Over time the cholesterol dries and forms a hard plaque, which causes further injury to the walls of the arteries.
In response to this additional harm, the immune system releases other factors called cytokines. These are powerful inflammatory molecules that attract more white blood cells and perpetuate the whole cycle, causing persistent injury to the arteries.

Click the icon to see an image of atherosclerosis.

Evidence is growing that the inflammatory response may be present not only in local plaques in single arteries but also throughout the arteries leading to the heart.

Blockage in the Arteries. Eventually these calcified (hardened) arteries become narrower (a condition known as stenosis).

As this narrowing and hardening process continues, blood flow slows and prevents sufficient oxygen-rich blood from reaching the heart.
Such oxygen deprivation in vital cells is called ischemia. When it affects the coronary arteries, it causes injury to the tissues of the heart.
Injured inner vessel walls also fail to produce enough nitric oxide, a substance critical for maintaining blood vessel elasticity. (Nitric oxide has complex effects and may increase inflammation in the arteries.)
These narrow and inelastic arteries not only slow down blood flow but also become vulnerable to injury and tears.

Click the icon to see an image of coronary artery blockage

The End Result: Heart Attack. Heart attack can occur as a result of one or two effects of atherosclerosis.

(1) If the artery becomes completely blocked and ischemia becomes so extensive that oxygen-bearing tissues around the heart die.

(2) If the plaque itself develops fissures or tears. Blood platelets adhere to the site to seal off the plaque, and a blood clot (thrombus) forms. A heart attack can then occur if the formed blood clot completely blocks the passage of oxygen-rich blood to the heart.

Click the icon to see an image of the developmental process of atherosclerosis.

Angina is the primary symptom of coronary artery disease and, in severe cases, of a heart attack. It is typically experienced as chest pain and occurs when the heart muscle does not get as much blood (hence as much oxygen) as it needs for a given level of work (ischemia). Angina is usually referred to as one of two states:

Click the icon to see an image about angina.

Stable Angina (which is predictable)
Unstable Angina (which is less predictable and a sign of a more serious situation)

Angina itself is not a disease. Much evidence indicates that onset of angina less than 48 hours before a heart attack may be protective, possibly by conditioning the heart to resist the damage resulting from the attack. Angina may be experienced in different ways and can be mild, moderate, or severe.

Click the icon to see an image of angina.

Specific factors are typically considered in determining whether symptoms indicate angina:

Quality of the pain. Angina pain is typically described by patients as squeezing, heavy, suffocating, or griplike. It is rarely described as stabbing or burning. Changing one's position or breathing in and out does not affect the pain. The intensity of the pain does not always relate to the severity of the medical problem. Some people may feel a crushing pain from mild ischemia, while others might experience only mild discomfort from severe ischemia. In some cases, the patient experiences shortness of breath, fatigue, or palpitations instead of pain. In others, the ischemia is entirely asymptomatic ("silent ischemia").
Duration. A typical angina attack lasts minutes. If it is more fleeting or lasts for hours, it is probably not angina.
Location. Pain is usually in the chest under the breast bone. It often radiates to the neck, jaw, or left shoulder and arm. Less commonly, patients report symptoms that radiate to the right arm or back.
Triggers of Angina. Angina is usually triggered by physical exertion, emotional stress, or exposure to cold.
Factors that Relieve Angina. Angina is usually relieved by rest or by taking nitroglycerine under the tongue.

Stable Angina. Stable angina is predictable chest pain. Although less serious than unstable angina, it can be extremely painful. It is usually relieved by rest and responds well to medical treatment (typically nitroglycerin). Any event that increases oxygen demand can cause an angina attack. Some typical triggers include:

Exercise
Cold weather
Emotional tension
Large meals

Angina attacks can occur at any time during the day, but most occur between 6 a.m. and noon.

Unstable Angina and Acute Coronary Syndrome. Unstable angina is a much more serious situation and is often an intermediate stage between stable angina and a heart attack, in which an artery leading to the heart (a coronary artery) becomes completely blocked. A patient is usually diagnosed with unstable angina under one or more of the following conditions:

Pain awakens a patient or occurs during rest.
A patient who has never experienced angina has severe or moderate pain during mild exertion (walking two level blocks or climbing one flight of stairs).
Stable angina has progressed in severity and frequency within a 2-month period, and medications are less effective in relieving its pain.

Unstable angina is now usually discussed as part of a condition called acute coronary syndrome (ACS). ACS also includes people with a condition called NSTEMI (non ST-segment elevation myocardial infarction) -- also referred to as non-Q wave heart attack. With NSTEMI, the blood tests suggest a developing heart attack. These conditions are less severe than heart attacks but may develop into full-blown attacks without aggressive treatment. [See In-Depth Report #12: Heart attack and acute coronary syndrome.]

Prinzmetal's Angina. A third type of angina, called variant or Prinzmetal's angina, is caused by a spasm of a coronary artery. It almost always occurs when the patient is at rest. About two-thirds of people with it have severe atherosclerosis in at least one major blood vessel. Irregular heartbeats are common, but the pain is generally relieved immediately with standard treatment.

Click the icon to see an image of a coronary artery spasm.

Silent Ischemia. Some people with severe coronary artery disease do not experience angina pain. This condition is known as silent ischemia, which some experts attribute to abnormal processing of heart pain by the brain. This is a dangerous condition because patients have no warning signs of heart disease. Some studies suggest that people with silent ischemia experience higher complication and mortality rates than those with angina pain. (Angina pain may actually protect the heart by conditioning it before a heart attack.)

Syndrome X. Syndrome X is a condition that occurs when patients have atypical angina chest pain. Their electrocardiograms are abnormal during a stress test, but they have no signs of blocked arteries. It is more likely to occur in women. Although it unclear what causes this condition, imaging tests suggest that Syndrome X may also be caused by ischemia, as is angina.

Prognosis

According to a 2007 report, nearly 16 million Americans have coronary artery disease. In the U.S., coronary artery disease is the leading killer of both men and women. In 2004, nearly 500,000 people died because of CAD. On the positive side, heart attack mortality rates have been declining. Half of men and 63% of women who die of heart disease do not have angina or other warning symptoms prior to their fatal attacks. Although at this time no tests can reliably predict whether a heart attack will occur, experts estimate that up to 30% of fatal attacks and many follow-up surgeries could be avoided with healthy lifestyle changes and by sticking to medical treatments. Two-thirds of patients who have suffered a first heart attack, however, do not take the necessary steps to prevent another.

The following syndromes suggest different degrees of severity among patients with heart disease.

Stable Angina. This condition can usually be managed with lifestyle measures and medications, such as low-dose aspirin. The more severe the angina, however, the greater the chance for progressing to a more serious condition.

Acute Coronary Syndromes (ACS). ACS includes severe and sudden heart conditions that require aggressive treatment but have not developed into a full-blown heart attack. ACS refers to either unstable angina or NSTEMI (non ST-segment elevation myocardial infarction). NSTEMI is also known as non Q-wave myocardial infarction.

Angina is a specific type of pain in the chest caused by inadequate blood flow through the blood vessels (coronary vessels) of the heart muscle (myocardium).

Unstable angina is potentially serious and chest pain is persistent, but blood tests do not show markers for heart attack.
With NSTEMI, the blood tests suggest a developing heart attack, but, most likely, injury in the arteries is less serious than with a full-blown heart attack.

Most discussions of the treatment of unstable angina now refer to acute coronary syndrome. Doctors use the presence of a number of factors to help predict which ACS patients are most at risk for developing a heart attack.

First, patients are categorized by whether they have a history of heart disease or risk factors for heart disease (such as diabetes, high blood pressure, peripheral artery disease) or other complicating conditions (such as lung disease, heart failure). The doctor also evaluates the severity of the angina. Other factors that pose a high risk for ACS include:

Age 65 years or older
Evidence of severe heart tissue injury
Having a lighter weight
Having a history of severe chronic angina
Having abnormal lung sounds called rales (a bubbling or crackling sound) on examination
ST-segment deviation
Having either very slow or very fast heat beats
Having very low blood pressure

Heart Attack. A full-blown heart attack occurs with severe damage to the heart, which blocks oxygen.

ANYONE WHO BELIEVES THEY ARE HAVING A HEART ATTACK SHOULD IMMEDIATELY CALL THE EMERGENCY MEDICAL SYSTEM (911 IN THE UNITED STATES).

People with known heart disease and any unusual chest pain or other symptoms of heart attack that do not clear up with medications should go to the hospital. The degree of pain and the specific symptoms before a heart attack vary greatly among individuals. Symptoms can be abrupt, gradual, or intermittent.

Chest Pain. People with heart disease or risk factors should be concerned about any chest pain, usually precipitated by exercise or stress, that interrupts normal activities and does not clear up after resting or taking angina medications. Chest symptoms might be experienced as follows:

Pain is typically felt as a crushing weight against the chest, accompanied by profuse sweating. The pain may radiate to the left shoulder and arm, the neck or jaw, and even infrequently to the right arm. The arm may be tingling or numb.
Some people may have only a tingling sensation or a sense of fullness, squeezing, or pressure in the chest.
In some patients with a history of heart disease, chest pain is mild. Such patients may have experienced unexplained fatigue, depression, and ill health within a month of a heart attack. Although chest pain is the classic symptom, it occurs in only about half of patients with a heart attack.

Other Common Symptoms.

Nausea, vomiting, and cold sweats
A feeling of indigestion or heartburn
Fainting
A great fear of impending death, a phenomena known as angor animi

Atypical Symptoms. Some studies suggest that nearly half of patients with heart attack do not have chest pain as the primary symptom. Common atypical symptoms of a heart attack include:

Shortness of breath
Cardiac arrest
Dizziness, weakness, and fainting
Abdominal pain

Patients most likely to have atypical symptoms are women and the very elderly (although they can certainly have classic heart attack symptoms as well).

In one study, 52% of elderly people with acute coronary syndrome had atypical symptoms that included shortness of breath, nausea, profuse sweating, pain in the arms, and fainting. Such symptoms were more likely to occur in people with personal or family history of heart disease.
Before a heart attack, women are more likely than men to be nauseous and experience pain high in the abdomen or chest. Their first symptom may be extreme fatigue after physical activity rather than chest pain. Chest pain in women is also more likely to be caused by non-heart problems than in men.

Symptoms That Are Less Likely to Indicate a Heart Attack. The following symptoms are less likely to be due to a heart attack:

Sharp pain brought on by lung movements or coughing
Pain that is mainly or only in the middle or lower abdomen
Pain that can be pinpointed with the top of one finger
Pain that can be reproduced by moving or pressing on the chest wall or arms
Pain that is constant and lasts for hours (although no one should wait hours if they suspect they are having a heart attack)
Pain that is very brief and lasts for a few seconds
Pain that spreads to the legs

However, the presence of these symptoms does not always rule out a serious heart event.

Chest pain is a very common symptom in the emergency room, but heart problems account for only 10 - 33% of all episodes.

The most common causes of chest pain are muscular and bone problems. Problems affecting the ribs and chest muscles include injured muscles, fractures, arthritis, spasms, and infections.

Other causes of chest pain include:

Anxiety attacks
Gastrointestinal disorders (gallstone attacks, peptic ulcer disease, hiatal hernia, heartburn)
Asthma
Spasm in the coronary artery
Abnormalities of the heart muscle
Rupture of the aorta
Collapsed lung
Acute inflammation of the heart
Blood clot in the lung
High thyroid levels (hyperthyroidism)
Anemia
Vasculitis (a group of disorders that cause inflammation of the blood vessels)
Exposure to high altitudes (rare)

Individuals who experience symptoms of a heart attack should take the following actions:

For angina patients, take one nitroglycerin dose either as an under-the-tongue tablet or in spray form at the onset of symptoms. Take another dose every 5 minutes up to three doses or when the pain is relieved, whichever comes first.
Call 911 or the local emergency number. This should be the first action taken if angina patients continue to experience chest pain after taking the full three doses of nitroglycerin. However, only 20% of heart attacks occur in patients with long-standing angina. Therefore, anyone who has heart disease or risk factors for it and experiences heart attack symptoms should contact emergency services.
The patient should chew an aspirin (250 - 500 mg) and be sure that emergency health providers are informed of this so an additional dose is not given.
Patients with chest pain should go immediately to the nearest emergency room, preferably traveling by ambulance. They should not drive themselves.

Click the icon to see an image about heart attack symptoms.

Click the icon to see another image about heart attack symptoms.

Risk Factors

Over 13 million Americans have had angina, a heart attack, or both. Each year, about 1.2 million people will experience a serious heart event. About 25% of all Americans have one or more risk factors for heart disease. Most risk factors for heart disease are related to lifestyle and environmental factors.

Over the past decades, heart disease rates declined in both men and women as they quit smoking and improved dietary habits. This rate, however, has stabilized in recent years, most likely because of the dramatic increase in obesity in the U.S. and other industrialized nations. There have also been minimal changes in other risk factors, including smoking, sedentary behavior, and blood pressure control. Some risk factors cannot be changed, including age, gender, and genetics. Nevertheless, their effects can still be modified with healthy lifestyle changes.

Heart disease may be prevented with a healthy diet and regular exercise, and by quitting smoking if you smoke. Follow your health care provider's recommendations for the treatment and prevention of heart disease.

The American Heart Association guidelines for preventing heart disease recommend:

Improve Cholesterol. People with at least two risk factors and a 10-year risk for heart disease or stroke of more than 20% should aim for LDL levels of less than 100 mg/dl. Statins are now used in more cases.

Keep Blood Pressure Low. People in normal health should have a blood pressure reading of 120/80 mm Hg or less. According to the latest guidelines, blood pressure readings of 120/80 are considered normal, readings of 140/90 or higher indicate hypertension, and readings in between the two are called pre-hypertension. Patients with diabetes or chronic kidney disease should maintain blood pressure readings of 130/80 mm Hg or less, while others should be no higher than 140/90 mm Hg.

Exercise. Everyone in normal health should engage in at least moderate physical activity for a minimum of 30 minutes on most, if not all, days of the week.

Healthy Diet. Everyone should aim for a diet that contains a healthy balance of fruits, vegetables, grains, fish, nuts, legumes, poultry, lean meat, and low-fat dairy items. Avoid saturated fats and trans-fatty acids.

Quit Smoking. Also avoid exposure to secondhand smoke.

Maintain Weight. People should aim for a BMI index of 18.5 - 24.9.

Taking Aspirin. People whose risk for heart disease within 10 years is 10% or more should take a low-dose aspirin every day, unless they have medical reasons to avoid aspirin.

Control Diabetes. People with diabetes should aim for fast blood glucose levels of less than 110 mg/dl and hemoglobin A1C or less than 7%.

Control Atrial Fibrillation. People with atrial fibrillation should use anticoagulants to reduce the risk for blood clots.

Age. About 85% of people who die from heart disease are over the age of 65.

In 2007, the American Heart Association issued updated guidelines focusing on prevention of heart disease in women. The new guidelines recommend:

Healthy diet (fresh fruits and vegetables, low-fat dairy products, salt and saturated fat restrictions, alcohol moderation)
Eating oily fish (such as salmon) at least twice a week. Women with existing heart disease should consider taking fish oil supplements of 850 – 1,000 mg eicosapentaenoic acid (EPA) and docosahexaenoic acid (DPA).
Increased physical activity (60 – 90 minutes, preferably 7 days a week)
Quitting smoking
Low-dose aspirin therapy for all women age 65 years and older who can safely take aspirin. High-risk women may require 75 – 325 mg / day; lower-risk women may benefit from 81 mg a day or 100 mg every other day.

Genetic Factors. Genetics are involved in increasing the likelihood of developing important risk factors such as diabetes and high blood pressure. For example, one genetic variant called apolipoprotein E4 (ApoE4) affects cholesterol levels, particularly those associated with heart disease.

Ethnicity. African-American women face the highest risk for death from heart disease, and their rate of heart attacks is increasing. (Mortality rates in men do not differ much by race.) Native American men have a lower risk for heart disease than Caucasian men, and Hispanics have the lowest risk for heart disease of all major American population groups.

African-Americans face a number of biologic and social dangers to their hearts.

They have a higher prevalence of diabetes and hypertension than do Caucasians.
They tend to have poorer diets, higher stress levels, and less access to health care.
All African-Americans risk discrimination in obtaining optimal treatments, but women may be at particular risk for unequal treatment. In one study in which female actors portrayed heart patients, African-American women were 60% less likely to receive aggressive (and expensive) diagnostic tests than African-American men or any Caucasians, even though they presented with similar symptoms.
While African-Americans comprise 13% of the U.S. population, African-Americans have comprised only 2 - 9% of subjects in most major research trials, so knowledge about their specific risks is limited.
Some African-Americans with coronary artery disease appear to have a genetic trait that increases the danger of triglycerides, which may be particularly hazardous for women.

Click the icon to see an image about ethnicity and heart disease risks.

Cholesterol. In spite of its bad press, cholesterol is an essential nutrient necessary for many cellular functions. However, when certain cholesterol levels rise in the blood, they can have dangerous consequences, depending on the type of cholesterol. Low-density lipoprotein (LDL) cholesterol is the "bad" cholesterol responsible for many heart problems. Triglycerides are another type of lipid (fat molecule) that can be bad for the heart. High-density lipoprotein (HDL) cholesterol is the "good" cholesterol that helps protect against heart disease. Doctors test for a "total cholesterol" profile that includes measurements for LDL, HDL, and triglycerides. The ratio of these lipids can affect heart disease risk.

For example, according to one study, men with total cholesterol levels over 240 mg/dl have a risk that is two to four times higher than men whose cholesterol is below 200. A number of studies have demonstrated that reducing LDL and total cholesterol levels and boosting high-density lipoprotein (HDL) levels can improve survival and prevent heart attacks in people with and without heart disease.

It is very difficult to measure LDL levels by themselves, but LDL levels can be reliably calculated by the Friedewald formula: LDL=TC-HDL-TG/5. (LDL=low-density lipoprotein; TC= total cholesterol; HDL=high-density lipoprotein; TG=triglycerides.)

Click the icon to see an image about serum cholesterol.

Cholesterol Goals. In 2004, the National Cholesterol Education Program updated its clinical practice guidelines. The new recommendations set lower treatment goals for LDL levels based on a patient's risk factors for heart disease.

These risk factors include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides

Having two or more of these risk factors indicates a greater than 20% chance of having a heart attack within 10 years.


Risk Level	Goal (d/L)	Optimal Goal(d/L)
Very High Risk	70	70
High Risk	100	70
Moderate Risk	130	100
Low Risk	160	130

LDL cholesterol, together with other risk factors for heart disease, is the best determinant for whether cholesterol therapy is needed and whether it is working properly. In particular, the new guidelines emphasize lower LDL levels and earlier treatment for people with coronary artery disease, or other forms of atherosclerosis, and diabetes.


Total Cholesterol Goals	LDL Goals	HDL Goals	Triglyceride Goals
Less than 200 mg/dL is desirable. Between 200 and 239 is borderline. Over 240 is high.	70 mg/dL or less is the new goal for very high-risk patients (recent heart attack; current active or unstable cardiovascular or cerebrovascular disease; or two multiple risk factors as defined above.) Below 100 mg/dl is optimal for everyone. It should be the goal for high-risk people including those with existing heart disease, diabetes, or two or more risk factors for heart disease; 70 mg/dL is an optimal goal for these individuals. 130 mg/dl or below for people with two or more risk factors; 100 mg/dL is the optimal goal. 160 mg/dl or less for people at less risk (one or zero risk factors); 130 mg/dL is the optimal goal. Anything over 160 is high with levels over 190 being very high. LDL levels over 190 require medication even with no other cardiac risk factors present.	Levels above 40 mg/dL are desirable; levels above 60 mg/DL are optimal.	Below 150 mg/dL is normal. 150-199 is borderline high. 200-499 is high. Over 500 is very high.
*Risk factors for heart disease include a family history of early heart problems before age 55 for men, before age 65 for women, smoking, high blood pressure, diabetes, being older (over 45 for men and 55 for women), and having HDL levels below 35 mg/dl. People with two or more of these risk factors may have a 10-year risk of heart attack that exceeds 20%, and may therefore need to aim for LDL levels of 100 mg/dL or below.

Other Lipids. Elevated levels of other fatty molecules (lipids) are also now thought to be important indicators of heart disease risk. Studies are finding an elevated risk for angina and first heart attacks in people with elevated levels of lipoprotein(a), or lp(a). This lipoprotein falls somewhere in density between HDL and LDL and may have some properties that increase the risk for blood clots. Some experts suggest, however, that high levels of lp(a) may merely be markers of late-stage atherosclerosis, not a cause.

[See In-Depth Report #23: Cholesterol; and In-Depth Report #43: Heart-healthy diet.]

High blood pressure, or hypertension, has long been a proven cause of coronary artery disease. Blood pressure is categorized as normal, prehypertensive, and hypertensive (which is further divided as Stage 1 or 2 according to severity). High blood pressure is generally considered to be a blood pressure reading greater than or equal to 140 mm Hg (systolic) or greater than or equal to 90 mm Hg (diastolic). Blood pressure readings in the prehypertension category (120 - 139 systolic or 80 - 89 diastolic) indicate an increased risk for developing hypertension. [See Table Blood Pressure Ranges.]

A normal blood pressure reading is 120/80 mm Hg or lower. Most people with high blood pressure should aim for a goal of below 140/90 mm Hg. Patients with certain health problems should aim lower (blood pressure in patients with kidney disease, heart failure, or diabetes should be equal to or lower than 130/80 mm Hg.)

Click the icon to see an image about hypertension.


Blood Pressure Category	Ranges for Most Adults (systolic/diastolic)
Normal Blood Pressure (systolic/diastolic)	Systolic below 120 mm Hg Diastolic below 80 mm Hg
Prehypertension (Formerly Classified as Normal to High-Normal Blood Pressure)	Systolic 120 to 139 mm Hg Diastolic 80 to 89 mm Hg (NOTE: 139/89 or below should be the minimum goal for everyone. People with diabetes or chronic kidney disease should strive for 130/80 or less.)
Mild Hypertension (Stage 1)	Systolic 140 to 159 mm Hg Diastolic 90 to 99 mm Hg
Moderate-to-Severe Hypertension (Stage 2)	Systolic over 160 mm Hg and/or Diastolic over 100 mm Hg
Note: If one of the measurements is in a higher category than the other, the higher measurement is usually used to determine the stage. For example, if systolic pressure is 165 (Stage 2) and diastolic is 92 (Stage 1), the patient would still be diagnosed with Stage 2 hypertension. A high systolic pressure should be a major focus of concern in most adults.

American obesity is at epidemic levels in all age groups. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels are usually high while HDL (beneficial cholesterol) levels tend to be low, both risk factors for heart disease. Obesity has other effects (hypertension, increase in inflammation) that pose major risks to the heart.

Click the icon to see an image of childhood obesity.

Obesity is particularly hazardous when it is one of the components of the metabolic syndrome. This syndrome is diagnosed when three of the following are present: abdominal obesity, low HDL cholesterol, high triglyceride levels, high blood pressure, and insulin resistance. Metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. A 2002 study estimated that 24% of the population now has this condition. Obesity is highly linked with type 2 diabetes, and diabetes itself poses a significant risk for high cholesterol levels and heart disease.

Some obese patients with coronary artery disease may consider having bariatric surgery (stomach bypass) to lose excess weight. The weight lost after surgery can help improve blood pressure, cholesterol, blood sugar and other factors associated with CAD. A 2005 study reported that bariatric surgery is safe for patients with CAD who cannot lose weight with diet and exercise, which should always be tried first.

[See In-Depth Report #53: Weight control and diet.]

People who are sedentary are almost twice as likely to suffer heart attacks as are people who exercise regularly. Exercise has a number of effects that benefit the heart and circulation, including:

Improving cholesterol and lipid levels
Reducing inflammation in the arteries
Assisting weight loss programs
Helping to keep blood vessels flexible and open

Studies continue to show that physical activity and avoiding high-fat foods are the two most successful means of reaching and maintaining heart healthy levels of fitness and weight.

Experts have been attempting to define how much exercise is needed to produce heart benefits. In 2002, a well-conducted study on overweight adults confirmed previous research that reported beneficial changes in cholesterol and lipid levels even when people performed low amounts of moderate or high intensity exercise (walking or jogging 12 miles a week). However, more intense exercise is required to significantly change cholesterol levels, notably by increasing HDL (the so-called good cholesterol). Overweight people who have trouble losing pounds can still achieve considerable heart benefits by exercising. Resistance (weight) training has also been associated with heart protection. Exercises that train and strengthen the chest muscles may prove to be very important for patients with angina.

Click the icon to see an image about exercise.

Click the icon to see an image about hypertension and lifestyle changes.

Some studies suggest that for the greatest heart protection, it is not the duration of a single exercise session that counts but the total daily amount of energy expended. Therefore, the best way to exercise may be in multiple short bouts of intense exercise, which can be particularly helpful for older people.

Sudden strenuous exercise (such as snow shoveling and mowing lawns) puts many people at risk for angina and heart attack. Activities that involve raising the arms above the head may also be risky. Patients with angina should never exercise shortly after eating. People with risk factors for heart disease should seek medical clearance and a detailed exercise prescription. And all people, including healthy individuals, should listen carefully to their bodies for signs of distress as they exercise. [See In-Depth Report #29: Exercise.]

Heart disease and stroke are the leading causes of death in people with diabetes. People with diabetes are at risk for the following heart-risk conditions, and the more of these conditions they have, the worse the outlook.

High blood pressure (hypertension). Up to 75% of cardiovascular problems in people with diabetes may be due to hypertension.
Very unhealthy cholesterol and lipid balances (high triglyceride levels and lower HDL).
Blood clotting problems.
Impaired nerve function (neuropathy), which can also damage the heart. Some experts estimate that the mortality rates from neuropathy-related heart conditions range from 15 - 53%.

People with both diabetes and heart disease may have a higher risk for silent ischemia, a condition in which people have blocked arteries but do not experience the angina, the chest pain that signals heart disease. [See In-Depth Report #9: Diabetes - type 1; or In-Depth Report #60: Diabetes - type 2.]

Peripheral artery disease (PAD) occurs when atherosclerosis affects the extremities, particularly the feet and legs. The major risk factors for heart disease and stroke are also the most important risk factors for PAD. (The combination of such conditions with PAD also produces more severe forms of heart or circulatory disease.) Although signs of heart disease are detected in only 20 - 40% of patients with PAD after an initial diagnosis, studies suggest that when intense heart-diagnostics tests are performed, such as angiography or thallium stress tests, co-existing heart disease is detected in up to 90% of all PAD patients. [See In-Depth Report #102: Peripheral artery disease.]

Smokers in their 30s and 40s have a heart-attack rate that is five times higher than their nonsmoking peers. Cigarette smoking may be directly responsible for at least 20% of all deaths from heart disease, or about 120,000 deaths annually. Smoking cigars may increase the risk of early death from heart disease, although evidence is much stronger for cigarette smoking. Although heavy cigarette smokers are at greatest risk, a 2002 study suggested that people who smoke as few as three cigarettes a day are at higher risk for blood vessel abnormalities that endanger the heart. Regular exposure to passive smoke also increases the risk of heart disease in nonsmokers. [See In-Depth Report #41: Smoking.]

Eating habits can be protective or dangerous to the heart. Avoiding saturated fats and trans-fatty acids is particularly important for controlling cholesterol.

Diet plays an important role in the health of the heart. In 2006, the American Heart Association (AHA) issued revised diet and lifestyle recommendations. The current guidelines recommend:

Balance calorie intake and physical activity to achieve or maintain a healthy body weight. (Controlling weight, quitting smoking, and exercising regularly are essential companions of any diet program. Try to get at least 30 minutes, and preferably 60 – 90 minutes, of daily exercise.)
Consume a diet rich in a variety of vegetables and fruits. Vegetables and fruits that are deeply colored (spinach, carrots, peaches, berries) are especially recommended as they have the highest micronutrient content.
Choose whole-grain, high-fiber foods. These include fruits, vegetables, and legumes (beans). Good whole grain choices include whole wheat, oats/oatmeal, rye, barley, brown rice, buckwheat, bulgur, millet, and quinoa.
Consume fish, especially oily fish, at least twice a week (about 8 ounces/week). Oily fish such as salmon, mackerel, and sardines are rich in the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Consumption of these fatty acids is linked to reduced risk of sudden death and death from coronary artery disease.
Limit daily intake of saturated fat (found mostly in animal products) to less than 7% of total calories, trans fat (found in hydrogenated fats, commercially baked products, and many fast foods) to less than 1% of total calories, and cholesterol (found in eggs, dairy products, meat, poultry, fish, shellfish) to less than 300 mg per day. Choose lean meats and vegetable alternatives (such as soy). Select fat-free and low-fat dairy products. Grill, bake, or broil fish, meat, and skinless poultry.
Use little or no salt in your foods. Reducing salt can lower blood pressure and decrease the risk of heart disease and heart failure.
Cut down on beverages and foods that contain added sugars (corn syrups, sucrose, glucose, fructose, maltrose, dextrose, concentrated fruit juice, honey.)
If you consume alcohol, do so in moderation. The AHA recommends limiting alcohol to no more than 2 drinks per day for men and 1 drink per day for women.

[See In-Depth Report #43: Heart-healthy diet.]

Stress. The effects of mental stress on heart disease are controversial. Stress can affect the heart when it activates the sympathetic nervous system (the automatic part of the nervous system that affects many organs, including the heart). Some studies suggest an association between acute stress and a higher risk for serious cardiac events, such as heart rhythm abnormalities and heart attacks, in people with heart disease. However, not all studies report strong evidence that stress has any effect on the heart, particularly in people without any history of heart disease. [See In-Depth Report #31: Stress.]

Depression. Depression increases the severity of heart attack and may even worsen a patient's response to medication for heart disease. Although people with heart disease may become depressed, this does not explain entirely the link between the two problems. Data suggest that depression itself may be a risk factor for heart disease as well as its increased severity.

A number of studies indicate that depression has biologic effects on the heart, including blood clotting and heart rate. One study, for example, reported an association between depression and a greater risk for death from heart problems even in people without a history of heart disease. Even mild depression, which includes feelings of hopelessness experienced over many years, may harm the heart. A 2007 study suggested that depressive symptoms (fatigue, loss of appetite) may be a sign of thickening arteries, the early stage of coronary artery disease. [See In-Depth Report #8: Depression.]

Benefits of Moderate Drinking. Several studies have found heart protection from moderate intake of alcohol (one or two glasses a day). Moderate alcohol consumption can help boost HDL levels. Alcohol may also prevent blood clots and inflammation. Although red wine is most often cited for healthful properties, any type of alcoholic beverage appears to have similar benefit.

Adverse Effects of Heavy Drinking. By contrast, heavy drinking harms the heart. In fact, heart disease is the leading cause of death in alcoholics. Evidence suggests that people who consume more than three drinks a day have abnormal blood clotting factors. Heavy alcohol consumption can raise blood pressure, and binge drinking may increase the risk for hemorrhagic stroke (caused by bleeding in the brain). Large doses of alcohol can trigger irregular heartbeats, which can be dangerous in people with existing heart disease.

Pregnant women and people who can't drink moderately should not drink at all.

Homocysteine and Vitamin B Deficiencies. Deficiencies in the B vitamins folate (known also as folic acid), B6, and B12 have been associated with a higher risk for heart disease in some studies. Such deficiencies produce higher blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. Researchers have been studying whether vitamin B supplements can reduce homocysteine levels and, consequently, heart disease risks.

Several major 2006 studies indicated that while B vitamin supplements do help lower homocysteine levels, they have no effect on heart disease outcomes. The studies, published in the New England Journal of Medicine, examined patients who had either recently had a heart attack or suffered from diabetes or heart disease. Results showed a similar number of heart attacks and strokes among patients who took B vitamins and those who received placebo. Some experts think that homocysteine may be a marker for heart disease rather than a cause of it.

Click the icon to see the benefits of vitamin B.

Click the icon to see the food sources of vitamin B.

C-Reactive Protein. C-reactive protein is a product of the inflammatory process. Evidence increasingly suggests that high levels may predict future heart disease. It is not known if the protein plays any causal role or whether it is simply a marker for other factors in the disease process.

C. pneumoniae and Other Infectious Organisms. Some microorganisms and viruses have been under suspicion for triggering the inflammation and damage in the arteries that contribute to heart disease. The strongest evidence to date supports a possible role from Chlamydia (C.) pneumoniae (a non-bacterial organism that causes mild pneumonia in young adults). C. pneumoniae has been detected in plaques in the arteries of patients with heart disease. In some studies, evidence of previous infection has been associated with a higher risk for heart events.

Other studies also suggest that cytomegalovirus (CMV), a common virus, may have similar effects. Many people, however, have been infected with these organisms, and no clear association has been found with any of these infections.(H. pylori, the bacteria that causes peptic ulcers, has also been studied for heart effects, but evidence is very weak on any link.)

Erectile Dysfunction. Recent research suggests that erectile dysfunction may be a warning sign of coronary artery disease, even in men who are not considered at risk for the condition. Some studies indicate that men with erectile dysfunction have higher levels of C-reactive protein and more symptoms of atherosclerosis than men without erectile problems.

Periodontal Disease. A number of studies support an association between periodontal disease and cardiovascular disorders. According to a 2003 major analysis, periodontal (gum) disease is associated with a 20% higher risk for ischemic stroke and heart disease. (The added risk may be even higher in adults under 65.) Recent evidence is pointing to the inflammatory response as the common element.

Click the icon to see an image of gum disease.

Anemia. Anemia has adverse effects on the heart and increases the severity of cardiac conditions, including heart failure and heart attacks. A 2002 study suggested that anemia may even be a risk factor for heart disease itself. Blood transfusions after a heart attack improve survival rates in elderly patients who are anemic.

Iron Overload. An inherited disease called hemochromatosis, in which the intestinal tract absorbs too much iron from food, has been associated with atherosclerosis and heart attack. About 10% of Caucasians carry the gene for this condition. There is no strong evidence that excess iron levels in people without hemochromatosis can contribute to heart disease.

Sleep Apnea. Obstructive sleep apnea is a condition in which tissues in the upper throat collapse at intervals during sleep, thereby blocking the passage of air. It has been strongly associated with high blood pressure and obesity, but is also associated with heart disease and heart attacks, regardless of these risk factors. Some evidence suggests that obstructive apneas cause an increase in stiffness and inflammation in the arteries.

Some inborn or natural conditions are not risk factors themselves but have been associated with a higher incidence of heart disease or its consequences:

Factors Before Birth and In Infancy. Low weight at birth and in the womb has been associated with later heart disease in a few studies. Some suggest, however, that this may just reflect poor nutrition in the mother, which appears to affect life-long risk.

Seasonal Differences. More deaths from heart disease occur in December and January, and the fewest in the summertime. Although lower temperatures and snow shoveling may play a role in some cases, more winter deaths have been reported even in warm regions. Holiday stress or fewer daylight hours have been suggested as other reasons for these higher winter rates.

Physical Characteristics. Male pattern baldness, hair in the ear canals, and creased earlobes are associated with a higher risk for heart disease in Caucasian males.

Click the icon to see an image of an ear lobe crease.

Diagnosis

Many tests can diagnose possible heart disease. The choice of which (and how many) tests to perform depends on the patient's risk factors, history of heart problems, and current symptoms. Usually the tests begin with the simplest and may progress to more complicated ones.

Doctors routinely check for high blood pressure and unhealthy cholesterol levels in all older adults. Specific tests are also important in people who may have risk factors or symptoms of diabetes. Doctors may also test for homocysteine, the protein albumin, and blood clotting factors, especially fibrinogen.

An electrocardiogram (ECG) measures and records the electrical activity of the heart. Between 25 - 50% of people who suffer from angina or have silent ischemia, however, have normal ECG readings. The waves measured by the ECG correspond to the contraction and relaxation pattern of the different parts of the heart. Specific waves seen on an ECG are named with letters:

The electrocardiogram (ECG, EKG) is used extensively in the diagnosis of heart disease, from congenital heart disease in infants to myocardial infarction and myocarditis in adults. Several different types of electrocardiogram exist.

P. The P wave is associated with the contractions of the atria (the two chambers in the heart that receive blood from outside).
QRS. The QRS is a series of waves associated with ventricular contractions. (The ventricles are the two major pumping chambers in the heart.)
T and U. These waves follow the ventricular contractions.

The most important wave patterns in diagnosing and determining treatment for heart disease and heart attack are called ST elevations and Q waves.

A depressed or horizontal ST wave suggests some blockage and the presence of a heart disease, even if there is no angina present. (This finding, however, is not very accurate, particularly in women, and can occur without heart problems).
ST elevations and Q waves are the most important wave patterns in diagnosing and determining treatment for a heart attack. They suggest that an artery to the heart is blocked, and that the full thickness of the heart muscle is damaged. ST segment elevations do not always mean the patient has a heart attack. And, some heart attack patients do not have elevated ST segments. Other factors are important in making a diagnosis.

The primary value of exercise stress tests is not to detect coronary artery disease but to help determine the severity and predict the outcome of an existing heart condition. It is considered for the following people:

Patients with possible or probable angina and low or intermediate risk for adverse heart events.
Selected adults who do not have symptoms of heart disease but are at moderate risk to high risk for developing heart disease (a 10 - 20% chance within 10 years). Moreover, heart blockage without angina (silent ischemia) may suggest a more severe condition, at least in men.

Basic Procedure. A stress test (exercise tolerance test) monitors the patient's heart rhythms, blood pressure, and clinical status. It can tell how well the heart handles work and if parts of the heart have decreased blood supply. A typical stress test involves:

The patient walks on a treadmill or rides a stationary bicycle. Exercise continues until the heart is beating at least 85% of its maximum rate, until symptoms of heart trouble occur (changes in blood pressure, heart rhythm abnormalities, angina, fatigue), or the patient simply wants to stop.
For patients who cannot exercise, the doctor may administer dobutamine or arbutamine, which are drugs that simulate the stress of exercise.
An ECG is used to monitor heart rhythms during a stress test. (An echocardiogram or more advanced imaging technique may also be used to visualize the actions of the heart and blood flow.)

More than 25% of patients stop exercising before they reach their own maximum limits because of fear of a heart event. Patients should be reassured that the activities performed in the test under the guidance of a professional are safe.

Interpreting Results. To accurately assess heart problems, experts look at a number of findings derived from the ECG and other tools during exercise. They include:

Exercise capacity. This is a measure of a person's capacity to reach certain metabolic rates.
Heart rate and ST waves. On ECGs, doctors specifically look for abnormalities in part of the wave tracing called an ST segment. A certain type of ST segment depression may suggest the presence of heart disease. However, gender, drugs and other medical conditions can affect the ST segment. Using a measurement that adjusts the ST segment to heart rate improves accuracy.
Dukes Treadmill Score. This important score uses the number of minutes a patient can exercise and other factors that are present in patients with exercise-limiting angina.
Heart rate recovery.
Chronotropic index. This is the percentage of the heart-rate reserve that is used during the exercise. A result of 80% or less suggests a significant risk for serious heart problems in most patients.
Changes in systolic blood pressure.

Using these and other measures, doctors can determine risk fairly accurately, particularly for men of any age with chronic stable angina. The test has limitations, however, and some are significant. For example, a 2002 study indicated that in patients with suspected unstable angina the chances for a future adverse heart event remain high even if the exercise test shows low risk. In addition, for many reasons, the test is less accurate in women, and an echocardiogram may be a more accurate procedure for them. About 10% of patients, particularly younger people, will have false positive test results. In such cases, test results indicate abnormalities when there are no heart problems.

An echocardiogram is a noninvasive test that uses ultrasound images of the heart. This test is more expensive than an ECG, but it can be very valuable, particularly when used with a stress test, to detect the location and extent of heart muscle damage. It appears to be more accurate for women than ECG stress tests, but at this time it is not routinely recommended as a replacement for most women.

Computed tomography (CT) scans used alone or with ECG may be used to detect calcium deposits on the arterial walls, which are strong indicators of current and future coronary artery disease. The presence of calcium does not always signify narrowing of the arteries. But, the absence of calcification in the arteries indicates the patient has no risk for heart disease.

Advanced CT techniques are improving accuracy:

Click the icon to see an image of a CT scan.

Electron Beam Computed Tomography. Electron beam computed tomography (EBCT) is a CT technique that scans the heart so quickly that the motion of the heart appears frozen. This procedure identifies calcification and stratifies cardiac risk accurately.
Multidetector Computed Tomography. Another CT technique called multidetector computed tomography (MDCT) is able to take pictures of the entire heart in 1 millimeter slices in the time it takes for a patient to hold one breath. A 2006 study indicated that MDCT tends to have a high “false-positive” rate (indicating disease when it is not actually there), but for some patients the test may be helpful in ruling out coronary artery disease.

Some expert groups recommend CT scans in selected patients who have an intermediate risk (10 - 20% chance of heart disease within 10 years). For some of these patients, EBCT may be preferred over exercise stress testing, but most experts recommend a stress test as the main diagnostic tool. In general, the use of these expensive imaging tests is probably not very helpful for people at low or high risk. (For people with high risk, the additional information from these tests would not add much value.) More research is needed to determine the benefits of CT scanning in specific individuals.

Radionuclide procedures use imaging techniques and computer analyses to plot and detect the passage of radioactive tracers through the region of the heart. Such tracing elements are typically given intravenously. Radionuclide imaging is useful for diagnosing and determining:

Severity of unstable angina when less expensive diagnostic approaches are unavailable or unreliable
Severity of chronic coronary artery disease
Success of surgeries for coronary artery disease.
Whether a heart attack has occurred

Various imaging techniques may be used with radionuclide procedures, including:

Planar scintigraphy uses a special overhead camera and is the oldest scanning technique.
Single-photon emission computed tomography (SPECT) uses a camera that rotates around the patient and takes pictures of "slices" of the heart. It is more accurate than planar imaging in precisely locating problems in the arteries.
Positron-emission tomographic (PET) scanners employ multiple rings that surround the patients, which detect and record atomic particles (photons) that are emitted by the tracer elements (such as radioactive oxygen, nitrogen, or carbon). It is more expensive and less widely available than SPECT.

Myocardial Perfusion (Blood Flow) Imaging Test (also called the Thallium Stress Test). This radionuclide test is typically used with an exercise stress test to determine blood flow to the heart muscles. It is a reliable measure of severe heart events. It may be useful in determining the need for angiography if CT scans have detected calcification in the arteries. About a minute before the patient is ready to stop exercising, the doctor administers a radioactive tracer into the intravenous line. (Tracers include thallium, technetium, or sestamibi.) Immediately afterwards, the patient lies down for a heart scan, usually with a planar scintigraphy or with SPECT. If the scan detects damage, more images are taken 3 or 4 hours later. Damage due to a prior heart attack will persist when the heart scan is repeated. Injury caused by angina, however, will have resolved by that time.

Radionuclide Angiography. This is a technique for visualizing the chambers and major blood vessels of the heart. It uses an injected radioactive tracer and can be performed during exercise, at rest, or with use of stress-inducing drugs. It is an excellent test for assessing the heart's pumping action and for determining the severity of coronary artery disease. It is an alternative to echocardiograms in certain situations.

Click the icon to see an internal view of the heart.

Magnetic Resonance Angiography (MRA). MRA is a very promising noninvasive imaging technique that can provide three-dimensional images of the major arteries to the heart and identify disease with high accuracy. Experts believe this approach will eventually be a good alternative to angiography.

Click the icon to see an image of a MRI.

Angiography is an invasive test. It is used for patients who show strong evidence for severe obstruction on stress and other tests, and for patients with acute coronary syndrome.

A narrow tube is inserted into an artery, usually in the leg or arm, and then threaded up through the body to the coronary arteries.
A dye is injected into the tube, and an x-ray records the flow of dye through the arteries.
This process provides a map of the coronary circulation, revealing any blocked areas.

Click the icon to see an image of dye in the coronary artery.

Major complications include stroke, heart attacks, and kidney damage. These risks are very low (about 0.1%), however, if the procedure is done in an experienced medical center (one that performs at least 300 of these operations every year). Allergic reactions can also occur. The procedure is expensive, and between 10 - 30% of patients who have this procedure have normal results.

When heart cells become damaged, they release different enzymes and other molecules into the bloodstream. Elevated levels of such markers of heart damage in the blood or urine may help predict a heart attack in patients with severe chest pain and help determine treatment. Some of these factors include:

Troponins. The proteins cardiac troponin T and I are released when the heart muscle is damaged. Both are proving to be among the best diagnostic indications of heart attacks. They help to identify many individuals with ACS who might otherwise be misdiagnosed.
Creatine kinase myocardial band (CK-MB). CK-MB has been a standard marker, but the MB fraction is not as accurate as troponin levels, since elevated levels can appear in people without heart injury.
Myoglobin. Myoglobin is a protein found in heart muscles. It is released early in the injured heart, and it may be useful in combination with CK-MB and the troponins.
Newer biomarkers, including C-reactive protein (CRP), homocysteine, B-type natriuretic peptide (BNP), urinary albumin, and fibrinogen.

Several 2006 studies that evaluated how well biomarkers predict risk of heart events concluded that they do not provide much more useful information than standard risk factors (high blood pressure, unhealthy cholesterol levels, diabetes). At this time, most experts feel that these standard disease risk factors provide the best predictors of the likelihood of developing coronary artery disease, heart attack, or stroke.

Managing Heart Disease

The approach for managing any degree of coronary artery disease involves lifestyle changes. Depending on severity and individual conditions, patients may need one or more medications, surgery, or both.

Healthy diet, regular exercise and quitting smoking if you are a smoker may prevent heart disease. Follow your health care provider's recommendations for treatment and prevention of heart disease.

Experts have come up with a mnemonic device (ABCDE) for remembering 10 factors that are fundamental for management of stable angina and coronary artery disease:

A. Aspirin and anti-angina drugs

B. Blood pressure and beta-blockers

C. Cholesterol-lowering drugs (typically statins) and cigarettes (stopping)

D. Diet and diabetes control

E. Exercise and education

Unstable angina is now usually classified with non-Q myocardial infarction as acute coronary syndrome (ACS) in professional discussions of treatments. ACS usually requires more aggressive treatments, including surgery. [ACS is more fully discussed in In-Depth Report #12: Heart attack and acute coronary syndrome.]

Click the icon to see an image about angina.

Anti-Clotting Medications

Anti-clotting drugs that inhibit or break up blood clots are used at every stage of heart disease. They are generally classified as either antiplatelets or anticoagulants. All anti-clotting therapies carry the risk of bleeding, which can lead to dangerous situations, including stroke.

A thrombus is a blood clot that forms in a vessel and remains there. An embolism is a clot that travels from the site where it formed to another location in the body. Thrombi or emboli can lodge in a blood vessel and block the flow of blood in that location depriving tissues of normal blood flow and oxygen. This can result in damage, destruction (infarction), or even death of the tissues (necrosis) in that area.

Antiplatelet Drugs. These drugs prevent formation of blood platelets. Platelets are very small disc-shaped blood cells that are important for blood clotting.

Aspirin. Aspirin is an antiplatelet. It is the most common anti-clotting drug. Nearly anyone with existing heart disease or at risk for it is advised to take a low-dose aspirin every day.
Thienopyridines. Clopidogrel (Plavix) and ticlopidine (Ticlid) are thienopyridines, another type of anti-platelet drug.
Glycoprotein IIb/IIIa Inhibitors. These powerful blood-thinning drugs include abciximab (ReoPro, Centocor), eptifibatide (Integrilin), tirofiban (Aggrastat), and lamifiban. They are administered intravenously in the hospital and are used after angioplasty surgery and stent placement.

Click the icon to see an image about blood.

Anticoagulants. Anticoagulants help thin blood and include:

Heparin
Warfarin (Coumadin)
Direct thrombin inhibitors

Aspirin. Aspirin is known as a nonsteroidal anti-inflammatory drug (NSAID). It stops blood platelets, which are major clotting factors, from sticking together to form a blood clot. A daily low-dose aspirin (75 - 325 mg) is usually the first choice for preventing heart disease in high-risk individuals. Aspirin can prevent by 25 – 50% the risk of heart attacks and death in people with existing heart disease and a history of heart attack. It also reduces the risk for stroke. According to a 2006 review, aspirin works equally well for both men and women.

Click the icon to see an image about stomach ulcers.

Side effects from prolonged use of aspirin may include stomach ulcers and bleeding. (There may be a slight increased risk for bleeding-related strokes, which are very uncommon, however. Furthermore, this risk may be outweighed by protection against the more common type of stroke, which is caused by artery blockage.)

Clopidogreland Ticlopidine. Clopidogrel (Plavix) and ticlopidine (Ticlide) are anti-platelet drugs known as thienopyridines. When taken with aspirin, these drugs can significantly reduce the risk for heart attack and stroke in patients with acute coronary syndrome (unstable angina or early signs of heart attack). The combination of aspirin and a thienopyridine is essential for patients who have a drug-eluting stent. According to a 2007 American Heart Association advisory, patients who have a drug-eluting stent must take both aspirin and a thienopyridine for at least 1 year after the stent is inserted. Many experts recommend clopidogrel instead of ticlopidine because ticlopidine has been associated with dangerous blood disorders, particularly thrombocytopenia.

Clopidogrel is also recommended for patients who are undergoing angioplasty. For patients having coronary bypass surgery, it should be withheld for at least 5 -7 days prior to surgery because of a significant bleeding risk. Researchers are investigating whether clopidogrel and aspirin together are better than aspirin alone in reducing the risks following coronary bypass surgery. A 2006 study suggested that for some patients with heart disease, clopidogrel plus aspirin does not work better than aspirin alone for preventing a first heart attack or stroke.

Click the icon to see an image of the developmental process of atherosclerosis.

Click the icon to see an image about atherosclerosis.

Anticoagulants are drugs that prevent or delay blood coagulation and the formation of blood clots. Heparin has been the standard anticoagulant, but a number of drugs are now available that are proving to be better choices in many cases.

Standard (Unfractionated) Heparin. The heparin referred to as unfractionated heparin has been the standard for years and is used alone or in combination with aspirin for managing unstable angina. It is no longer the recommended first choice, however, for this patient group. It must be intravenously administered and monitored with frequent blood tests. The major complication is thrombocytopenia (a severe drop in platelets). This condition is extremely serious and can become life-threatening, particularly with bleeding in various body tissues. Alternatives include low-molecular weight heparin and direct thrombin inhibitors.

Low-Molecular Weight Heparin. Enoxaparin (Lovenox), dalteparin (Fragmin), tinzaparin (Innohep) are drugs known as low-molecular weight heparins (LMWHs). Many doctors now recommend these drugs over standard heparin for patients with unstable angina (unless bypass surgery is being planned). They have similar rates of survival, recurring angina, and bleeding as standard heparin. However, they pose lower risks for heart attack, repeat angioplasties, and thrombocytopenia. They require injections but do not require the ongoing monitoring that standard heparin does. Patients may even be able to self-administer LMWHs as people with diabetes do insulin.

Warfarin. Warfarin (Coumadin) is an oral anticoagulant. It prevents clots by inhibiting vitamin K. Warfarin is used with aspirin after a heart attack to prevent another one and to prevent blood clots in patients with atrial fibrillation. Warfarin is also proving to be more effective than aspirin for preventing heart attacks in patients with acute coronary syndromes. Warfarin therapy poses a dangerous risk for bleeding and blood coagulation must be monitored with frequent blood tests.

Direct Thrombin Inhibitors (DTIs). Direct thrombin inhibitors are a more recent group of anti-coagulants. The first DTI was hirudin, a natural substance derived from the saliva of leeches. New forms include argatroban (Novastan), bivalirudin (Angiomax), danaparoid (Orgaran), lepirudin (Refludan), desirudin (Revasc), and ximelagatran (Exanta). Many of these drugs are used along with warfarin and may be good options for patients who develop thrombocytopenia with heparin use. DTIs may prove to be superior to standard heparin for patients with acute coronary syndrome.

Other Medications

Nitrates have been used in the treatment of angina for over 100 years. These drugs release nitric oxide, thereby relaxing the smooth muscles in blood vessels. Many nitrate preparations are available. The most commonly used are nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates can be absorbed from the gastrointestinal tract (oral tablet), skin (ointment or patch), or from under the tongue (sublingual tablet or spray).

Rapid Acting Nitrates. Rapid-acting nitrates are used to treat acute attacks. Nitroglycerin is the most widely used drug for this purpose. It can be administered under the tongue (sublingually or as a spray) or pocketed between the upper lip and gum (buccally) and can relieve angina within minutes. The procedure for taking nitroglycerin during an attack is as follows:

At the onset of an angina attack, the patient administers one sublingual or buccal tablet or one metered dose of the spray.
If the pain is not relieved within 5 minutes the patient takes a second dose; a third can be taken after another 5 minutes if symptoms persist.
If pain continues after a total of three doses in 15 minutes, the patient should go immediately to the nearest emergency room.

Nitroglycerin is very volatile so its potency can be easily lost. Patients should take the following precautions:

Keep no more than 100 tablets on hand, stored in their original container.
When first opened, the cotton filler should be discarded, and the cap screwed on tightly immediately after each use.
A supply should always be kept close at hand in case of an attack, with the rest kept in a cool dry place.

Intermediate to Long-Term Nitrates. Sublingual tablets of isosorbide dinitrate have a somewhat slower onset of action than nitroglycerin and are useful for preventing exercise angina. Ointments, patches, and oral tablets are used for longer-term prevention of angina attacks:

Transdermal patches are applied in the morning to any hair- or injury-free area on the chest, back, stomach, thigh, or upper arm. Hands should be washed after each patch or ointment application, and sites of application should be rotated to avoid skin irritation.
Nitroglycerin ointment is applied by measuring out an even amount on an applicator paper and then placing, not rubbing or massaging, it on the chest, stomach, or thigh. Any ointment that remains from the previous application should be removed.

Long-acting forms may lose their effectiveness over time, so doctors generally schedule nitrate-free breaks to prevent tolerance. Some concern exists that nitrate-free periods might increase the risk for angina and adverse heart events. One large study, however, found no increased danger when patients used a nitroglycerine patch with scheduled breaks. The use of high blood pressure drugs known as ACE inhibitors may help prevent tolerance to nitrates.

Side Effects. Nitrates have many side effects, some of which can be serious.

Common side effects of nitrates include headaches, dizziness, nausea and vomiting, blurred vision, fast heartbeat, sweating, and flushing on the face and neck. Low blood pressure and dizziness can be relieved by lying down with the legs elevated. These effects are significantly worsened by alcohol, beta-blockers, calcium channel blockers, sildenafil (Viagra), and certain antidepressants. The doctor may prescribe medicines to lessen these side effects. Patients should contact their doctor if these side effects are persistent or severe.

Serious side effects requiring immediate medical help include fever, joint or chest pain, sore throat, skin rash (especially on the face), unusual bleeding or bruising, weight gain, and swelling of the ankles.

Withdrawal. Withdrawal from nitrates should be gradual. Abrupt termination may cause angina attacks.

Beta-blockers are useful for preventing angina attacks and reducing high blood pressure. They reduce the heart's oxygen demand by slowing the heart rate and lowering blood pressure. They are recognized for reducing deaths from heart disease and from heart surgeries, including angiography and coronary bypass. Beta-blockers are the drugs of choice for older patients with stable angina and may also be beneficial for people with silent ischemia. They are, however, less useful for the treatment of Prinzmetal’s angina. Beta-blockers are often prescribed along with other drugs such as nitrates, calcium channel blockers, or statins. A 2006 study suggested that beta-blockers and statins may help stabilize coronary artery disease and prevent the development of heart attacks.

Specific Beta-blockers. Beta-blockers include propranolol (Inderal), carvedilol (Coreg), bisoprolol (Zebeta), acebutolol (Sectral), atenolol (Tenormin), labetalol (Normodyne, Trandate), metoprolol (Lopressor, Toprol-XL), and esmolol (Brevibloc). A nasal spray form of propranolol appears to be very helpful in reducing exercise-induced angina attacks.

Side Effects. Beta-blocker side effects include fatigue, lethargy, vivid dreams and nightmares, depression, memory loss, and dizziness. They can lower HDL (“good”) cholesterol. Beta blockers are categorized as non-selective or selective. Non-selective beta blockers such as carvedilol and propranolol can narrow bronchial airways. These beta-blockers should not be used by patients with asthma, emphysema, or chronic bronchitis.

Patients should never abruptly stop taking these drugs. The sudden withdrawal of beta-blockers can rapidly increase heart rate and blood pressure. The doctor may advise a patient to slowly decrease the dose before stopping completely.

Calcium channel blockers reduce heart rate and slightly dilate the blood vessels of the heart, thereby decreasing oxygen demand and increasing oxygen supply. They also reduce blood pressure. CCBs vary chemically, however, and although some are helpful, others may even be dangerous for certain patients with angina.

Click the icon to see an image of the anterior heart arteries.

Long-acting nifedipine (Adalat, Procardia) and nisoldipine (Sular) and newer CCBs, such as amlodipine (Norvasc) and nicardipine (Cardene), may be beneficial for some patients with angina. They can be considered alone for patients who cannot tolerate beta-blockers, but may provide the best results when used in combination with a beta-blocker. Studies suggest that they reduce the need for repeat angioplasties. Their effects on other outcomes, including mortality rates and heart attack, are less clear.
Short-acting CCBs, including short-acting forms of verapamil, diltiazem, nifedipine, and nicardipine, are helpful for many patients with Prinzmetal's angina. However, short-acting forms of certain CCBs, such as nifedipine and nisoldipine, have been associated with severe and even dangerous side effects, including an increase in heart attacks and sudden death in some patients with unstable angina. They also increase the risk for adverse effects in patients with stable angina. Short-acting CCBs are, therefore, not used for stable or unstable angina.

There is no strong evidence that any calcium channel blockers improve survival rates. Overdose can cause dangerously low blood pressure and slow heart beats. Patients with heart failure have a higher risk for death with these drugs and should not take them. No one taking any calcium channel blocker should withdraw abruptly because such action could dangerously increase the risk of high blood pressure. Note: Grapefruit and Seville oranges boost the effects of CCBs, sometimes to toxic levels. (Regular oranges do not appear to pose any hazard.)

Angiotensin converting enzyme (ACE) inhibitors are important heart-protective drugs, particularly for people with diabetes and high blood pressure. They reduce the production of angiotensin, a chemical that causes arteries to narrow, and so are commonly used to lower blood pressure. They may also reduce risk for heart attack, stroke, complications of diabetes, and death in patients at high risk for heart disease.

ACE inhibitors include captopril (Capoten), ramipril (Altace), enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), perindopril (Aceon), and lisinopril (Prinivil, Zestril).

Side Effects. Side effects of ACE inhibitors are uncommon but may include an irritating cough, excessive drops in blood pressure, and allergic reactions. In the past, doctors sometimes avoided giving aspirin to patients who were taking ACE inhibitors because the combination was believed to cause kidney problems. But, a 2005 study of patients with both coronary artery disease and heart failure found that taking aspirin and ACE inhibitord together is safe. The researchers also noted that taking aspirin with an ACE inhibitor can significantly reduce the risk of death for older patients with CAD and heart failure. [See In-Depth Report #14: High blood pressure.]

In 2004, the National Cholesterol Education Program issued updated recommendations on how to control cholesterol levels. These guidelines emphasize that patients should lower their LDL (“bad”) cholesterol and recommend that more people take LDL-lowering medication. Lowering LDL cholesterol and raising HDL (“good”) cholesterol can significantly reduce the risks of heart disease. Several different types of drugs (statins, bile-acid binding resins, niacin, and fibrates) are used to treat cholesterol. [See In-Depth Report #23: Cholesterol.]

Statins are the most important of these drugs. Brands include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). A major analysis of over 200 studies found that statins reduced the risk for heart problems by 60% and stroke by 17%. A 2005 review found that the more that statins lower LDL, the more they reduce CAD and other heart disease risks.

An important 2006 study found that aggressive treatment with statins may have the potential to reverse coronary artery disease. In the study, rosuvastatin reduced fatty plaque in the arteries in addition to improving LDL and HDL cholesterol levels. However, a follow-up 2007 study of rosuvastatin indicated that while the drug slowed the rate of atherosclerotic progression, it did not reverse heart disease. Future studies will continue to investigate this issue.

Side effects of statins may include stomach upset, headaches, skin rashes, muscle aches, sexual dysfunction, drowsiness, dizziness, nausea, constipation, and peripheral neuropathy (numbness or tingling in the hands and feet).

The main safety concern with statins is an uncommon condition called myopathy, which can cause muscle and joint pain and possible muscle damage. Doctors will immediately stop statin therapy if myopathy occurs. Patients should talk to their doctor about any unusual muscle discomfort or weakness, or if their urine becomes brown-colored. Statins can also affect the liver, particularly at higher doses, so patients taking these drugs should receive regular liver function tests.

Click the icon to see an image of cholesterol.

Influenza Vaccinations (Flu Shots). Evidence suggests influenza vaccinations help protect against adverse heart events (including after heart surgeries), stroke, and death from all causes in the elderly. Still, studies suggest that only two-thirds of at risk people are vaccinated, mostly because of unwarranted fears of ineffectiveness or adverse effects.

Antibiotics. Researchers have investigated antibiotics for treating patients with heart disease and past infection of the bacteria Chlamydia pneumoniae. Results from several recent large-scale clinical trials suggest that antibiotic treatment provides no benefit in preventing heart attack or other cardiac events in patients with coronary artery disease. In addition, a 2006 study indicated that short-term treatment with the antibiotic clarithromycin may increase the risk for death in patients with coronary artery disease. While it is still possible that C. pneumoniae may play a role in triggering inflammatory responses associated with ACS, antibiotic therapy is no longer considered appropriate for treatment or prevention of heart disease.

Ranolazine (Ranexa) was approved in 2006 for treatment of chronic angina. It is recommended for patients who have not responded to other angina drugs. Ranolazine is taken in combination with amlodipine, beta blockers, or nitrates. The drug appears to work better in men than in women

Gene Therapy and Angiogenesis. Proteins known as growth factors are being investigated for their ability to grow new blood vessels for supplying oxygen to the heart. After promising small trials, two large studies of genetically engineered forms of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF [GenerX]) failed to detect any benefits. Studies on therapies that actually genetically encode these proteins are underway.

Testosterone Supplements. Some trials using testosterone supplements or patches have reported improved exercise-induced blood flow in the coronary arteries and improvement in angina in some cases. Supplements of this male hormone, however, may increase the risk for prostate cancer. Experts suggest that testosterone be used only in older men with significant deficiencies in testosterone.

Selective Estrogen-Receptor Modulators (SERMs). Selective estrogen-receptor modulators (SERMs), including raloxifene (Evista), have been designed to produce the benefits of estrogen without its risks. They are thought to act like estrogen in some tissues but behave like estrogen blockers (antiestrogens) in others. Raloxifene may have some heart benefits, although it poses a risk for deep vein blood clots, which may have long-term implications for patients with heart problems. A major study is underway to determine its effects on the heart.

Surgery

Surgery is usually recommended for patients who have:

Unstable angina that does not respond promptly to medical treatment
Severe recurrent episodes of angina that last more than 20 minutes
Acute coronary syndrome
Severe coronary artery disease (severe angina, multi-artery involvement, evidence of ischemia), particularly if abnormalities are evident in the left ventricle of the heart, the main pumping chamber

Atherosclerosis is a disease of the arteries in which fatty material is deposited in the vessel wall, resulting in narrowing and eventual impairment of blood flow. Severely restricted blood flow in the arteries to the heart muscle leads to symptoms such as chest pain. Atherosclerosis shows no symptoms until a complication occurs.

Researchers have been investigating whether surgery offers any advantages if used as an early treatment for mild angina. A major analysis in 2003 reported that the use of angioplasty in patients with mild heart blockage did not reduce the risk for heart attack or death over the long term. A landmark 2007 study found that angioplasty was no better than drug therapy for preventing heart attack and stroke in patients with stable coronary artery disease. (For more information, see Angioplasty and Stents.)

Two effective surgical procedures for heart patients are:

Coronary artery bypass grafting (commonly called bypass or CABG)
Percutaneous coronary intervention (commonly called angioplasty or PCI), usually with coronary artery stent placement

Click the icon to see an image about bypass grafting.

Each of these procedures is described below.

Studies have generally reported similar survival rates with either procedure. There are some differences, however, and decision often depends on individual conditions. Patients considering surgery should discuss all options and risks with their doctor. No surgical procedure cures coronary artery disease, and patients must continue to rigorously maintain a healthy lifestyle and any necessary medications. For some patients, lifestyle changes and medications may be able to control the disease without surgery or angioplasty.

Considerations for Choosing Angioplasty with Stent Placement. Angioplasty has the following advantages for most patients. It is:

Less invasive than bypass. (Although a minimally invasive variation of bypass surgery may reduce this distinction.)
Less expensive than bypass. (Although the postoperative need for more medications and the high risk for repeat procedures to reopen the artery may reduce the long-term difference in cost between the two procedures.)
Life-saving emergency procedure for many patients with heart attacks. (The use of bypass after a heart attack has much higher mortality rates than when it is used electively and its use is controversial in heart attack patients.)

It has the following disadvantages:

The blood vessels can close up again (restenosis) so that patients require additional procedures. (New blood thinning drugs, coronary stent coatings, and radiation treatments may help to significantly reduce restenosis rates. However, there is also some indication that stents, especially drug-eluting stents, may increase the risk for blood clots.)
It is not as appropriate as bypass for many patients with angina (people with diabetes, elderly patients, or those with multi-vessel blockage). Increasingly, however, angioplasty is proving to be as safe and as effective as bypass in many high-risk patients. Patients should be sure to discuss with their doctors the relevant risks and benefits of angioplasty and bypass.

Considerations for Choosing Bypass. Bypass is usually the appropriate procedure in patients with high-risk conditions, such as:

Multi-vessel blockage. (In one report comparing surgery to angioplasty in patients with two or three blocked vessels, the mortality rate 1 year after bypass was 0.8% and after angioplasty was 2.5%. About 80% of patients in the study were men.)
Diabetes. (Bypass produces significantly higher survival rates in these patients. Some experts believe angioplasty should rarely, if ever, be used in this population.)
Being elderly.
Certain structural features, such as a left main artery narrowed by 50% or more or a very long diseased portion of the artery.

Considerations for Women. Studies have reported higher mortality rates in women than in men after any heart surgery. Some experts theorize that on average women may be older and sicker when they have a heart operation. A 2002 study, however, suggested that when women with acute coronary syndromes are given the same aggressive and early treatment as men are, their survival rates are equal or even better.

In addition to angioplasty and bypass procedures, a number of other procedures are available or under investigation for coronary artery disease. They include:

Atherectomy
Myocardial Laser Revascularization
Enhanced External Counterpulsation (EECP)

Coronary Artery Bypass Graft Surgery

Coronary artery bypass graft surgery (CABG) is a good alternative to angioplasty for many patients, but it is very invasive. The surgery involves the following processes:

Click the icon to see an animation about CABG.

The chest is opened, and the blood is rerouted through a lung-heart machine.
The heart is stopped during the procedure.
Large blood vessels supply the grafts, which are used to reroute the blood. The blood vessel grafts are transplanted in front of and beyond the blocked arteries, so the blood flows through the new vessels around the blockage.
The standard grafts now use arteries taken from the chest wall. Studies are reporting that with such grafts arteries remain open in 90% of cases after 15 years.
In general, patients with triple bypass procedures stay in the hospital for 5 days. Those with one-vessel bypass may be able to go home in 3 days.

Click the icon to see an illustrated series detailing a heart bypass surgery.

In spite of the invasive nature of this procedure, elective bypass procedures produce better long-term survival rates than angioplasty, particularly in patients with diabetes and multi-vessel blockage. Overall mortality rates after this procedure range from 1% to slightly over 2%. The risk for stroke or heart attack after a bypass operation ranges from 1.3 - 5%. Finding a surgeon who performs at least 100 of the procedures a year helps reduce the risk for complications.

Blood clots may form in the new graft, closing it up or narrowing the treated vessel over time. Therapy with aspirin and other anti-clotting drugs help keep the graft open and working properly. For long-term prevention of closure, as well as for slowing progression of atherosclerosis, aggressive treatment with cholesterol-lowering drugs may be more beneficial than standard anti-clotting drugs.

Bleeding is also a potential complication of CABG. Anti-bleeding (also called hemorrhage-sparing) drugs are sometimes used to limit blood loss in patients who undergo this surgery. In 2006, concerns were raised about one of these drugs, aprotinin (Trasylol). Data suggested that aprotinin seriously increased the risks for kidney failure, heart failure, and stroke.

An important study, published in 2007 in the Journal of the American Medical Association, compared aprotinin with two anti-fibrinolytic drugs, aminocaproic acid (Amicar) and tranexamic acid (Cyklokapron), which are also used to control blood loss. The study of nearly 4,000 patients who had CABG found that over a 5-year period, the death rate for patients who took aprotinin was 21%, and patients had a 48% increased risk of dying. By comparison, the death rate was 16% for aminocaproic acid, 15% for tranexamic acid, and 13% for no anti-bleeding drug. Because aprotinin is more expensive as well as potentially more dangerous than other anti-bleeding drugs, experts are now recommending against its use in CABG.

Minimally invasive bypass (also called buttonhole or keyhole bypass) surgeries are exciting advances in basic bypass surgery. Studies indicate good success of these procedures for patients with disease in single vessels. They are also being investigated for multiple vessels.

One variation of minimally invasive bypass uses a four-inch incision. The surgeon works on the front of the heart while it is beating slowly. To date, there have been no differences in cardiac events or later mental complications between this so-called off-pump procedure and the standard bypass procedure.
In another variation, the heart is stopped, and the patient is put on a machine that reroutes the blood through a device that keeps it oxygenated. Fiberoptic scopes and instruments are passed through a number of finger-sized incisions. The surgeon works on all sides of the heart, guided by a video image from a tiny camera inserted through a 4-inch incision.
Some advanced heart centers now use robotic systems, which allow the surgeon to perform extremely delicate maneuvers on tiny vessels through pencil-size incisions. They are not yet used for the whole bypass process.

Eventually, minimally invasive bypass procedures may prove to be less expensive, require a shorter hospital stay, and have fewer complications than conventional coronary artery bypass surgery -- or even angioplasty. At this time, however, they are experimental procedures, performed in only a few medical centers for select candidates. Long term-success rates are unknown.

Angioplasty and Stents

Percutaneous coronary intervention (PCI), also called angioplasty, involves procedures such as percutaneous transluminal coronary angioplasty (PTCA) that help open the blocked artery.

Click the icon to see an animation about percutaneous transluminal coronary angioplasty.

A typical angioplasty procedure follows these steps:

The cardiologist threads a narrow catheter (a tube) containing a catheter into the blocked vessel.
The doctor opens the blocked vessel using balloon angioplasty, in which the surgeon passes a tiny deflated balloon through the catheter to the vessel.
The balloon is inflated to compress the plaque against the walls of the artery, flattening it out so that blood can once again flow through the blood vessel freely.
In order to keep the artery open afterwards, surgeons use a device called a coronary stent, an expandable metal mesh tube that is implanted during angioplasty at the site of the blockage. (In some cases, a stent may be used as the initial opening device instead of balloon angioplasty.)
Once in place, the stent pushes against the wall of the artery to keep it open.

Click the icon to see an animation about percutaneous transluminal coronary angioplasty.

Complications occur in about 10% of patients (about 80% within the first day). Outcomes are better in hospital settings with experienced teams and backup.

Click the icon to see an illustrated series detailing coronary artery balloon angioplasty surgery.

The most important long-term complication is reclosure (restenosis), which can lead to heart attack if not treated with a repeat procedure. Stenting and other advances have helped significantly in preventing reclosure and reducing heart attack rates. Nevertheless, a repeat procedure is still needed to restore the opening in 10 - 15% of procedures that use stents.

PCI (angioplasty) has been proven to help reduce the frequency of angina attacks. It is commonly recommended for patients who have critically blocked arteries or have already had a recent, acute heart attack. PCI can also help improve survival and prevent heart attacks in patients with acute coronary syndrome (ACS). However, doctors have been uncertain about angioplasty’s benefits for survival and heart attack prevention in lower-risk patients with stable coronary artery disease.

In 2007, a landmark study was published in the New England Journal of Medicine and presented at the 2007 meeting of the American College of Cardiology. The COURAGE study found that PCI works no better than standard heart medication (drugs to control blood pressure, lower cholesterol, and prevent blood clots) in preventing heart attack, stroke, and hospitalization in patients with stable coronary artery disease. Based on this study’s findings, experts are now recommending angioplasty only for patients who have severe heart disease. For patients with stable heart disease, drug therapy may be sufficient enough treatment and allow them to safely defer having surgery.

Angioplasty is less invasive than bypass surgery, requiring only one night in the hospital. Recuperation takes about a week. Chest pain after the procedure is very common and usually due to problems other than ischemia. Mild chest pain is even more common when a stent is used, possibly because the artery is stretched.

Reclosure of the artery during or shortly after angioplasty often occurs. A number of anti-clotting drugs are used to help prevent this.

Aspirin and the anti-platelet drug clopidogrel (Plavix) are often used to prevent reclosure during the procedure.
A high dose of the anticoagulant heparin is typically given before the operation.
Intravenous glycoprotein IIb/IIIa inhibitors, powerful drugs that block platelets, also prevent reclosure after stenting in many high-risk patients, and evidence now strongly suggests that they reduce rates of heart attack and death. Eptifibatide (Integrilin) and tirofiban (Aggrastat) are the standard drugs used during angioplasty. They may be most effective if administered during angioplasty, rather than beforehand.

All of these drugs pose a risk for bleeding complications.

Narrowing or reclosing of the artery (restenosis) can occur within a year of angioplasty or even longer in 15 - 60% of angioplasty patients. Coronary stents, anti-clotting drugs, and other advances have reduced these events significantly, but have not eliminated the problem. Theories for the cause of restenosis include:

The release of oxidants (damaging unstable particles) at the surgical site may cause injury and activate immune factors that produce cellular overgrowth in smooth muscles of the blood vessels.
Other activities, including scarring, may remodel and narrow the blood vessels. (This is most likely the reason for restenosis in patients with stents.)

Symptoms of restenosis include chest pain on exertion. (Heart attacks, however, do not usually occur with such events.) The narrowing of the artery in this case is not due to blood clots, so anti-clotting drugs are not useful. Restenosis usually requires a repeat operation. A number of approaches, mostly investigative, have been developed to prevent restenosis after angioplasty.

Drug-Coated Stents. Stents coated with the drugs sirolimus (Rapamune) or paclitaxel (Taxol) have been increasingly used in the last several years. Drug-eluting stents (as they are also called) can help prevent restenosis. However, because drug-eluting stents reduce arterial tissue growth, they can increase the risks of blood clots. In late 2006, the FDA held several meetings to discuss the increased risks of blood clots associated with drug-eluting stents. The committees found that drug-eluting stents do appear to have a small increased risk of blood clots compared to bare metal stents, but not enough research has been conducted to fully determine their risks for heart attack and death.

Five studies published in the New England Journal of Medicine in March 2007 indicated that drug-eluting stents are safe and effective for patients with coronary artery disease when they are used for FDA-approved indications. Problems have arisen when these stents are used for “off-label” purposes in patients with more complicated health problems. There is still some concern as to whether all stents (both bare metal and drug eluting) are used too frequently for patients who may be better served by drugs or bypass surgery.

In February 2007, the American Heart Association and other professional organization issued an extremely important joint advisory statement. The statement advises that all patients who have drug-eluting stents must continue to take aspirin and clopidogrel (or, rarely, ticlopidine) for at least 1 year after the stent is inserted to reduce the risk of blood clots. Clopidogrel and ticlopidine are thienopyridine drugs that, like aspirin, help prevent blood platelets from clumping together. It is very important that patients who have drug-eluting stents take both aspirin and a thienopyridine drug. If for some reason patients cannot take a thienopyridine drug, they should receive a bare metal stent instead of a drug-eluting stent.

Coronary Artery Brachytherapy. Radiation treatment called coronary artery brachytherapy (Gamma One, Beta-Cath) can slow the cell growth in the arteries that causes restenosis. With this approach, any blockage in the stent is first removed, and a tube with an inflatable balloon is inserted. The surgeon then implants a temporary device that delivers radiation. Brachytherapy has shown excellent results in preventing restenosis and significantly reducing heart events and improving survival. Brachytherapy is also showing promise in preventing restenosis in stented artery grafts that were put in place after bypass surgery and later failed. However, several 2006 studies in the Journal of the American Medical Association indicated that drug-coated stents may work better than brachytherapy in preventing restenosis in failed stents. In these studies, the drug-coated stents were inserted inside the original bare metal stents.

Medications. A number of medications are being studied for prevention of restenosis, although benefits to date have been modest. Other drugs under investigation include statins, various anti-clotting drugs, and B vitamins.

Other Procedures. Other procedures under investigation to keep the arteries open use ultrasound, "soft" x-rays, and cryotherapy (very low temperatures).

Other Treatments

Transmyocardial laser revascularization (TMLR) applies laser energy directly to areas in the heart where blockage has occurred, creating 10 - 50 tiny channels. TMLR is recommended for patients with severe angina who have not responded to surgical bypass or angioplasty procedures. TMLR is not suitable for patients who have severely damaged heart muscles. A variant called percutaneous transmyocardial laser revascularization uses a small laser (a holmium YAG laser), which is smaller than the device used in TMLR and does not require open chest surgery and a general anesthetic.

Patients report improved symptoms and exercise tolerance. Both procedures carry risks for serious complications, however, including some that can be life-threatening. It is not clear if either TMLR procedure improves survival, and, in one study, the quality of life afterwards was less than with standard heart surgeries.

A noninvasive technique called enhanced external counterpulsation (EECP) has been used successfully by over a million people in China. The technique uses an air pump that inflates and deflates pressurized cuffs around the legs, causing blood to be pushed into the heart.

EECP may help patients with angina who have not had pain relief from nitrate drugs and who do not qualify as candidates for bypass or angioplasty. In different studies, it has relieved angina in over 75% of patients who used it and reduced the need for medication. The benefits persist, and there is some evidence that it produces actual cellular changes that benefit the heart. In 2002, the FDA approved EECP for the treatment of heart failure but some insurance companies still consider its use “experimental” and will not pay for it. EECP is not recommended for patients with arrhythmia, serious heart valve problems, or peripheral artery disease.

Atherectomy procedures clear the narrowed arteries by using an approach called debulking. All of these procedures use a catheter (a thin tube) that is inserted into an artery (usually in the groin) and threaded up to the blockage. Devices are inserted through the tube to remove the plaque. They include:

Rotational atherectomy, which uses a tiny cutter spinning at 2,500 rpm
Extractional atherectomy, which "shaves" the plaque
Directional atherectomy, which slices the plaques

Although they are successful in opening arteries, they offer no advantages over standard angioplasty and are used only for special cases.

Resources

www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.americanheart.org -- American Heart Association
www.acc.org -- American College of Cardiology

References

Boden WE, O'Rourke RA, Teo KK, Hartigan PM, Maron DJ, Kostuk WJ, et al. Optimalmedical therapy with or without PCI for stable coronary disease. N Engl J Med. 2007 Mar 26; [Epub ahead of print]

Crouse JR 3rd, Raichlen JS, Riley WA, Evans GW, Palmer MK, O'Leary DH, et al. Effect of rosuvastatin on progression of carotid intima-media thickness in low-risk individuals with subclinical atherosclerosis: the METEOR Trial. JAMA. 2007 Mar 28;297(12):1344-53. Epub 2007 Mar 25.

Eisenstein EL, Anstrom KJ, Kong DF, Shaw LK, Tuttle RH, Mark DB, et al. Clopidogrel use and long-term clinical outcomes after drug-eluting stent implantation. JAMA. 2007 Jan 10;297(2):159-68. Epub 2006 Dec 5.

Folsom AR, Chambless LE, Ballantyne CM, Coresh J, Heiss G, Wu KK, et al. An assessment of incremental coronary risk prediction using C-reactive protein and other novel risk markers: the atherosclerosis risk in communities study. Arch Intern Med. 2006 Jul 10;166(13):1368-73.

Garcia MJ, Lessick J, Hoffmann MH; CATSCAN Study Investigators. Accuracy of 16-row multidetector computed tomography for the assessment of coronary artery stenosis. JAMA. 2006 Jul 26;296(4):403-11.

Grines CL, Bonow RO, Casey DE Jr, Gardner TJ, Lockhart PB, Moliterno DJ, et al. Prevention of premature discontinuation of dual antiplatelet therapy in patients with coronary artery stents: a science advisory from the American Heart Association, American College of Cardiology, Society for Cardiovascular Angiography and Interventions, American College of Surgeons, and American Dental Association, with representation from the American College of Physicians. Circulation. 2007 Feb 13;115(6):813-8. Epub 2007 Jan 15.

Kastrati A, Mehilli J, Pache J, Kaiser C, Valgimigli M, Kelbaek H, et al. Analysis of 14 trials comparing sirolimus-eluting stents with bare-metal stents. N Engl J Med. 2007 Mar 8;356(10):1030-9. Epub 2007 Feb 12.

Lagerqvist B, James SK, Stenestrand U, Lindback J, Nilsson T, Wallentin L; SCAAR Study Group. Long-term outcomes with drug-eluting stents versus bare-metal stents in Sweden. N Engl J Med. 2007 Mar 8;356(10):1009-19. Epub 2007 Feb 12.

Lloyd-Jones DM, Liu K, Tian L, Greenland P. Narrative review: Assessment of C-reactive protein in risk prediction for cardiovascular disease. Ann Intern Med. 2006 Jul 4;145(1):35-42.

Maisel WH. Unanswered questions--drug-eluting stents and the risk of late thrombosis. N Engl J Med. 2007 Mar 8;356(10):981-4. Epub 2007 Feb 12.

Mangano DT, Miao Y, Vuylsteke A, Tudor IC, Juneja R, Filipescu D, et al. Mortality associated with aprotinin during 5 years following coronary artery bypass graft surgery. JAMA. 2007 Feb 7;297(5):471-9.

Mangano DT, Tudor IC, Dietzel C; Multicenter Study of Perioperative Ischemia Research Group; Ischemia Research and Education Foundation. The risk associated with aprotinin in cardiac surgery. N Engl J Med. 2006 Jan 26;354(4):353-65.

Mauri L, Hsieh WH, Massaro JM, Ho KK, D'Agostino R, Cutlip DE. Stent thrombosis in randomized clinical trials of drug-eluting stents. N Engl J Med. 2007 Mar 8;356(10):1020-9. Epub 2007 Feb 12.

Mosca L, Banka CL, Benjamin EJ, Berra K, Bushnell C, Dolor RJ, et al. Evidence-based guidelines for cardiovascular disease prevention in women: 2007 update. Circulation. 2007 Mar 20;115(11):1481-501.

Nicholls SJ, Tuzcu EM, Sipahi I, Grasso AW, Schoenhagen P, Hu T, et al. Statins, high-density lipoprotein cholesterol, and regression of coronary atherosclerosis. JAMA. 2007 Feb 7;297(5):499-508.

Rosamond W, Flegal K, Friday G, Furie K, Go A, Greenlund K, et al. Heart disease and stroke statistics--2007 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation. 2007 Feb 6;115(5):e69-171. Epub 2006 Dec 28.

Spaulding C, Daemen J, Boersma E, Cutlip DE, Serruys PW. A pooled analysis of data comparing sirolimus-eluting stents with bare-metal stents. N Engl J Med. 2007 Mar 8;356(10):989-97. Epub 2007 Feb 12.

Stewart JC, Janicki DL, Muldoon MF, Sutton-Tyrrell K, Kamarck TW. Negative emotions and 3-year progression of subclinical atherosclerosis. Arch Gen Psychiatry. 2007 Feb;64(2):225-33.

Stone GW, Moses JW, Ellis SG, Schofer J, Dawkins KD, Morice MC, et al. Safety and efficacy of sirolimus- and paclitaxel-eluting coronary stents. N Engl J Med. 2007 Mar 8;356(10):998-1008. Epub 2007 Feb 12.

Wang TJ, Gona P, Larson MG, Tofler GH, Levy D, Newton-Cheh C, et al. Multiple biomarkers for the prediction of first major cardiovascular events and death. N Engl J Med. 2006 Dec 21;355(25):2631-9.

Review Date:
4/16/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Heart attack and acute coronary syndrome

FitSugar — Wed, 08 Oct 2008 17:34:57 -0700

In This Report

Highlights
Introduction
Symptoms
Prognosis
Risk Factors
Diagnosis
Treatment
Medications
Surgery
Rehabilitation
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approval

In 2006, the FDA approved the use of clopidogrel (Plavix) for patients who have had a STEMI heart attack and who will not be having angioplasty. A STEMI is a very severe type of heart attack caused by sudden and total artery blockage.

Angioplasty and Stents

Surgery with angioplasty and stents that is performed more than 3 days after a heart attack offers no advantage over standard drug therapy for clinically stable patients, indicates an important 2006 New England Journal of Medicine study. Experts recommend that this procedure be performed to open blocked arteries within 12 hours of a heart attack.

Drug-Coated Stents

Drug-coated stents may be better than bare metal stents for patients who have had a STEMI heart attack, suggest several New England Journal of Medicine studies. However, recent research has raised concern that these types of stents increase the risk for blood clots.
Patients who have a drug-coated stent must take aspirin and clopidogrel (Plavix) for at least 1 year after the stent is inserted, according to an important 2007 advisory from the American Heart Association (AHA). The combination of these drugs can help prevent blood clots.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

NSAIDs such as acetaminophen (Tylenol), ibuprofen (Advil) should be used with caution by patients who have had a heart attack:

In 2007, the AHA warned that NSAIDs (with the exception of aspirin) and COX-2 inhibitors increase the risk of heart attack and stroke. The AHA is recommending that doctors change the way they prescribe these pain relievers for patients who have or are at risk for heart disease.
A 2006 Journal of the American Medical Association study suggested that the prescription NSAID diclofenac (Cataflam) carries a higher risk for heart attack than other NSAIDs.

Introduction

The heart is the human body's hardest working organ. Throughout life it continuously pumps blood enriched with oxygen and vital nutrients through a network of arteries to all parts of the body's tissues. In order to perform the arduous task of pumping blood to the rest of the body, the heart muscle itself needs a plentiful supply of oxygen-rich blood, which is provided through a network of coronary arteries. These arteries carry oxygen-rich blood to the heart's muscular walls (the myocardium).

Coronary artery disease is the most common cause of heart attacks. Coronary artery disease is the end result of a complex process called atherosclerosis (commonly called "hardening of the arteries"). This causes blockage of arteries (ischemia) and prevents oxygen-rich blood from reaching the heart. A full-blown heart attack occurs when blood flow to the myocardium is blocked and tissue death occurs from loss of oxygen, severely damaging the heart. The medical term for heart attack is myocardial infarction. [See In-Depth Report #3: Coronary artery disease.]

Click the icon to see an image of atherosclerosis.

Heart attack (or myocardial infarction) is the most serious outcome of atherosclerosis. It can occur as a result of one or two effects of atherosclerosis:

(1) If the artery becomes completely blocked and ischemia becomes so extensive that oxygen-bearing tissues around the heart die.

Click the icon to see an image of an acute myocardial infarction.

Angina is the primary symptom of coronary artery disease and is typically experienced as chest pain. There are two kinds of angina:

Stable Angina is predictable chest pain that can usually be managed with lifestyle measures and medications, such as low-dose aspirin.
Unstable angina is a much more serious situation than stable angina that is often an intermediate stage between stable angina and a heart attack. Unstable angina is part of a condition called acute coronary syndrome.

Acute coronary syndrome (ACS) is a severe and sudden heart condition that requires aggressive treatment, but has not developed into a full blown heart attack. Acute coronary syndrome includes:

Unstable angina. Unstable angina is a much more serious situation than stable angina. It is often an intermediate stage between stable angina and a heart attack.
NSTEMI (non ST-segment elevation myocardial infarction). This condition, also called non Q-wave myocardial infarction, is diagnosed when blood tests and ECGs suggest a developing heart attack. The injury in the arteries is less severe than with a full-blown heart attack.

Symptoms

ANYONE WHO BELIEVES THEY ARE HAVING A HEART ATTACK SHOULD IMMEDIATELY CALL THE EMERGENCY MEDICAL SYSTEM (911 IN THE UNITED STATES).

In people with known heart disease, any unusual chest pain or other symptoms of heart attack that do not clear up with medications are signals to go to the hospital. The degree of pain and the specific symptoms before a heart attack vary greatly among individuals. Onset can be abrupt, gradual, or intermittent.

Pain is typically felt as a crushing weight against the chest, accompanied by profuse sweating. The pain may radiate to the left shoulder and arm, the neck or jaw, and even infrequently to the right arm. The arm may be tingling or numb.
Some people may have only a tingling sensation or a sense of fullness, squeezing, or pressure in the chest.
In some patients with a history of heart disease, chest pain is mild. Such patients may have experienced unexplained fatigue, depression, and ill health within a month of a heart attack.

Although chest pain is the classic symptom, it occurs in only about half of patients with a heart attack.

Other Common Symptoms. Other common symptoms of a heart attack include:

Nausea, vomiting, and cold sweats
A feeling of indigestion or heartburn
Fainting
A great fear of impending death, a phenomena known as angor animi

Uncommon Symptoms. Some studies suggest that nearly half of patients with heart attack do not have chest pain as the primary symptom. Common atypical symptoms of a heart attack include:

Shortness of breath
Cardiac arrest
Dizziness, weakness, and fainting
Abdominal pain

Patients most likely to have atypical symptoms are women and the very elderly (although they can certainly have classic heart attack symptoms as well.)

In one study, 52% of elderly people with acute coronary syndrome had atypical symptoms that included shortness of breath, nausea, profuse sweating, pain in the arms, and fainting. Such symptoms were more likely to occur in people with personal or family history of heart disease.
Before a heart attack, women are more likely than men to be nauseous and experience pain high in the abdomen or chest. Their first symptom may be extreme fatigue after physical activity rather than chest pain. Chest pain in women is also more likely to be caused by non-heart problems than in men.

Symptoms That Are Less Likely to Indicate a Heart Attack. The following are symptoms that are more likely to be due to causes other than a heart event:

Sharp pain brought on by lung movements or coughing
Pain that is mainly or only in the middle or lower abdomen
Pain that can be pinpointed with the top of one finger
Pain that can be reproduced by moving or pressing on the chest wall or arms
Pain that is constant and lasts for hours (although no one should wait hours if they suspect they are having a heart attack)
Pain that is very brief and lasts for a few seconds
Pain that spreads to the legs

The presence of these symptoms, however, does not always rule out a serious heart event.

Chest pain is a very common symptom in the emergency room, but heart problems account for only 10% to a third of all episodes. High on the list of other causes of chest pain are the following:

The most common causes of chest pain are muscular and bone problems. Problems affecting the ribs and chest muscles include injured muscles, fractures, arthritis, spasms, and infections.
Anxiety attacks
Gastrointestinal disorders (gallstone attacks, peptic ulcer disease, hiatal hernia, heartburn)
Asthma
Spasm in the coronary artery
Abnormalities of the heart muscle itself
Rupture of the aorta, collapsed lung, acute inflammation of the heart, or a blood clot in the lung
Hyperthyroidism
Anemia
Vasculitis (a group of disorders that cause inflammation of the blood vessels)
Exposure to high altitudes (rare)

Immediately call 911 or the local emergency number.

If patients have been previously diagnosed with angina, they should take one nitroglycerin dose either as an under-the-tongue tablet or in spray form at the onset of symptoms. They should take another dose every 5 minutes up to three doses or when the pain is relieved, whichever comes first.

It should be noted, however, that only 20% of heart attacks occur in patients with long-standing angina.

Anyone who has heart disease or risk factors for it and experiences heart attack symptoms should immediately contact emergency services.

The patient should chew an aspirin (250 - 500 mg) and be sure that emergency health providers are informed of this so an additional dose is not given.

Patients who experience chest pain should go immediately to the nearest emergency room, preferably traveling by ambulance. They should not drive themselves.

Prognosis

Each year, an estimated 650,000 Americans will suffer a first heart attack, and 450,000 will have a recurrent episode. Currently, half of the men and 63% of the women who died of heart disease had no warning prior to their fatal attacks.

Heart attacks may be rapidly fatal, evolve into a chronic disabling condition, or lead to full recovery. The long-term prognosis for both length and quality of life after a heart attack depends on its severity and the preventive measures taken afterward.

About 88% of patients under age 65 who experience a heart attack can expect to return to work. About 12,600,000 Americans who have had heart attacks, angina, or both are alive today. However, within 6 years of a heart attack, 18% of men and 35% of women have a recurrent attack. And, about 22% of men and 46% of women develop heart failure.

Although no tests can absolutely predict whether another heart attack will occur, experts estimate that up to 30% of fatal attacks, and many follow-up surgeries, could be avoided with healthy lifestyle changes and adherence to medical treatments. Two-thirds of patients who have suffered a heart attack, however, do not take the necessary steps to prevent another.

Higher Risk Individuals. A heart attack is always more serious in certain people:

Elderly (particularly those who are thinner)
People with a history of heart disease or risk factors for heart disease
People with heart failure
People with diabetes
People on long-term dialysis

Women are more likely to die after a heart attack than men. The risk is highest in younger women (although in the younger population, the risk for having a first heart attack and then dying from it is very low). It is still unclear why heart attacks are more severe in this group.

Factors Occurring at the Time of a Heart Attack That Increase Severity. The presence of other conditions during a heart attack can contribute to a poorer outlook:

Arrhythmias (disturbed heart rhythms). A dangerous arrhythmia called ventricular fibrillation is a major cause of short-term death from heart attack. Such arrhythmias are more likely to occur within the first 4 hours and are associated with a high mortality rate. Patients who are successfully treated, however, have the same long-term prognosis as those who do not experience such arrhythmias.
Signs of severe physical damage to the heart may indicate a poorer outlook.
Shock. This very dangerous condition is associated with very low blood pressure, reduced urine levels, and cellular abnormalities. Shock occurs in about 7% of heart attacks. The incidence has not declined over recent years, although its survival rates have improved.
Heart block, also called atrioventricular (AV) block, is a condition in which the electric conduction of nerve impulses to specialized muscles in the heart is slowed or interrupted. Although heart block is dangerous, it can be treated effectively with a pacemaker, and it rarely causes any long-term complications in patients who survive it.

Heart attacks and acute coronary syndrome pose a high risk for stroke. According to a major 2002 study, the risk for stroke after heart attack is 2.5% in the first 6 months and 5% per year thereafter. In the study, patients with a higher risk (about 4%) for stroke within 6 months of a heart attack were older (over age 75), African-American, had a history of stroke, atrial fibrillation, hypertension, diabetes, or peripheral artery disease. Most people who fall into these categories have more than one of these risk factors.

Risk Factors

About 25% of all Americans have one or more risk factors for heart disease, increasing their risk for heart attack. Most risk factors for heart disease are related to lifestyle. Some risk factors, (such as age, gender, and ethnicity) cannot be changed. Nevertheless, overall risks can be reduced with healthy lifestyle changes. [See In-Depth Report #3: Coronary artery disease.]

The American Heart Association's guidelines for preventing heart disease recommend:

Keep Blood Pressure Low. People in normal health should have a blood pressure reading of 120/80 mm Hg or less. According to new guidelines, blood pressure readings of 120/80 are considered normal, readings of 140/90 or higher indicate hypertension, and readings in between the two are called pre-hypertension. Patients with diabetes or chronic kidney disease should maintain blood pressure readings of 130/80 mm Hg or less, while others should be no higher than 140/90 mm Hg.

Exercise. Everyone in normal health should engage in at least moderate physical activity for a minimum of 30 minutes on most -- if not all -- days of the week.

Quit Smoking. Also avoid exposure to second-hand smoke.

Maintain Weight. People should aim for a BMI index of 18.5 - 24.9.

Take Aspirin. People at high risk for heart disease should take a low-dose aspirin every day, unless they have medical reasons to avoid aspirin.

Control Diabetes. People with diabetes should aim for fast blood glucose levels of less than 110 mg/dl and hemoglobin A1C of less than 7%.

Control Atrial Fibrillation. People with atrial fibrillation should use anticoagulants to reduce the risk for blood clots.

The approach for managing acute coronary syndrome involves lifestyle changes and medications. Experts have come up with a mnemonic device (ABCDE) for remembering the factors that are fundamental for management of acute coronary syndrome:

A. Antiplatelets, anticoagulants, and ACE inhibitors

B. Blood pressure and beta-blockers

C. Cholesterol-lowering drugs (typically statins) and cigarettes (stopping)

D. Diet and diabetes control

E. Exercise and education

Age. About 85% of people who die from heart disease are over the age of 65.

Gender. Coronary artery disease and heart attacks are much more common in middle-aged men. Women have, on average, 10 - 15 more years of heart disease-free life than do men, but as women age, they catch up to men. Women are more likely to have angina than men are. Younger women with heart disease often do not have the same symptoms as their male counterparts and may be less likely to be diagnosed correctly. They are also more likely than men are to die after a heart attack. Evidence suggests that this is because women tend to be older and sicker than men at the time of a first attack. A 2002 study indicated, however, that with early aggressive treatment women with acute coronary syndrome do as well or better than men with the same condition and treatments.

Ethnicity. Of all major ethnic groups, African-American women face the highest risk for death from heart disease, and their rate of heart attacks is increasing. (Mortality rates in men do not differ much by race.) Native American men have a lower risk for heart disease than Caucasian men, and Hispanics have the lowest risk for heart disease of all major American population groups.

Timing of Heart Attack. A 2007 study suggested that patients who are admitted to a hospital on a weekend are less likely to receive aggressive heart attack treatment and less likely to survive than patients who are treated on a weekday. However, no one can predict when a heart attack will occur. The most important point is to get treatment quickly, regardless of the day of the week. And, if you think you having a heart attack, call an ambulance -- or have someone call for you -- to ensure prompt treatment. Do not drive yourself.

Cholesterol. Cholesterol is a white, powdery substance that is found in all animal cells and in animal-based foods (not in plants). In spite of its bad press, cholesterol is an essential nutrient necessary for many functions. However, when certain cholesterol levels rise in the blood, they can have dangerous consequences, depending on the type of cholesterol.

Low-density lipoprotein (LDL) cholesterol is the "bad" cholesterol responsible for many heart problems. Triglycerides are another type of lipid (fat molecule) that can be bad for the heart. High-density lipoprotein (HDL) cholesterol is the "good" cholesterol that helps protect against heart disease. Doctors test for a "total cholesterol" profile that includes measurements for LDL, HDL, and triglycerides. The ratio of these lipids can affect heart disease risk. [See In-Depth Report #23: Cholesterol.]

These risk factors include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)

Having two or more of these risk factors indicates a greater than 20% chance of having a heart attack within 10 years.


Risk Level	Goal (d/L)	OptimalGoal(d/L)
Very High Risk	70	70
High Risk	100	70
Moderate Risk	130	100
Low Risk	160	130


Total Cholesterol Goals	LDL Goals	HDL Goals	Triglyceride Goals
Less than 200 mg/dL is desirable. Between 200 and 239 is borderline. Over 240 is high.	70 mg/dL or less is the new goal for very high-risk patients (recent heart attack; current active or unstable cardiovascular or cerebrovascular disease; or two multiple risk factors as defined above.) Below 100 mg/dl is optimal for everyone. It should be the goal for high-risk people including those with existing heart disease, diabetes, or two or more risk factors for heart disease; 70 mg/dL is an optimal goal for these individuals. 130 mg/dl or below for people with two or more risk factors; 100 mg/dL is the optimal goal. 160 mg/dl or less for people at less risk (one or zero risk factors); 130 mg/dL is an optimal goal. Anything over 160 is high, with levels over 190 being very high. LDL levels over 190 require medication even with no other cardiac risk factors present.	Levels above 40 mg/dL are desirable; levels above 60 mg/dL are optimal.	Below 150 mg/dL is normal. 150-199 is borderline high. 200-499 is high. Over 500 is very high.
*Risk factors for heart disease include a family history of early heart problems before age 55 for men (before age 65 for women), smoking, high blood pressure, diabetes, being older (over 45 for men and 55 for women), and having HDL levels below 35 mg/dl. People with two or more of these risk factors may have a 10-year risk of heart attack that exceeds 20%, and may therefore need to aim for LDL levels of 100 mg/dL or below.


Blood Pressure Category	Ranges for Most Adults (systolic/diastolic)
Normal Blood Pressure (systolic/diastolic)	Systolic below 120 mm Hg Diastolic below 80 mm Hg
Prehypertension (Formerly Classified as Normal to High-Normal Blood Pressure)	Systolic 120 to 139 mm Hg Diastolic 80 to 89 mm Hg (NOTE: 139/89 or below should be the minimum goal for everyone. People with diabetes or chronic kidney disease should strive for 130/80 or less.)
Mild Hypertension (Stage 1)	Systolic 140 to 159 mm Hg Diastolic 90 to 99 mm Hg
Moderate-to-Severe Hypertension (Stage 2)	Systolic over 160 mm Hg and/or Diastolic over 100 mm Hg
Note: If one of the measurements is in a higher category than the other, the higher measurement is usually used to determine the stage. For example, if systolic pressure is 165 (Stage 2) and diastolic is 92 (Stage 1), the patient would still be diagnosed with Stage 2 hypertension. It should be strongly noted that a high systolic pressure should be a major focus of concern in most adults.

American obesity is at epidemic levels in all age groups. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels are usually high while HDL (beneficial cholesterol) levels tend to be low, both risk factors for heart disease. Obesity, in any case, has other effects (hypertension, increase in inflammation) that pose major risks to the heart.

Obesity is particularly hazardous when it is one of the components of the metabolic syndrome. This syndrome is diagnosed when three of the following are present: abdominal obesity, low HDL cholesterol, high triglyceride levels, high blood pressure, and insulin resistance. Metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. A 2002 study estimated that 24% of the population now has this condition. Obesity is highly linked with type 2 diabetes, in any case. And diabetes itself poses a significant risk for high cholesterol levels and heart disease. [See In-Depth Report #53: Weight control and diet.]

People who are sedentary are almost twice as likely to suffer heart attacks as are people who exercise regularly. Exercise has several effects that benefit the heart and circulation, including improving cholesterol and lipid levels, reducing inflammation in the arteries, assisting weight loss programs, and helping to keep blood vessels flexible and open. Studies continue to show that physical activity and avoiding high-fat foods are the two most successful means of reaching and maintaining heart healthy levels of fitness and weight.

Some studies suggest that people may gain the greatest heart protection benefit from the total daily amount of energy they expend, rather than from the length of a single exercise session. Therefore, the best way to exercise may be in multiple short bouts of intense exercise, which can be particularly helpful for older people.

Sudden strenuous exercise (such as snow shoveling and mowing lawns) can put people at risk for angina and heart attack. Activities that involve raising the arms above the head may also be risky. Patients with angina should never exercise shortly after eating. People with risk factors for heart disease should seek medical clearance and a detailed exercise prescription. And all people, including healthy individuals, should listen carefully to their bodies for signs of distress as they exercise. [See In-Depth Report #29: Exercise.]

High blood pressure (hypertension) --up to 75% of cardiovascular problems in people with diabetes may be due to hypertension.
Very unhealthy cholesterol and lipid balances (high triglyceride levels and lower high density lipoprotein).
Blood clotting problems.
Impaired nerve function (neuropathy), which can also damage the heart. In fact, some experts estimate that the mortality rates from neuropathy-related heart conditions ranges from 15 - 53%.

Patients with both diabetes and heart disease may have a higher risk for silent ischemia, a condition in which people have blocked arteries but do not experience the angina, the chest pain that signals heart disease [See In-Depth Report #9: Diabetes - type 1 ; or In-Depth Report #60: Diabetes - type 2.]

Eating habits can either protect or hurt the heart. Experts generally agree on the following heart-smart recommendations:

Choose fiber-rich food (whole grains, legumes, nuts) as the main source of carbohydrates, along with a high intake of fresh fruits and vegetables.
Avoid saturated fats (found mostly in animal products) and trans fatty acids (found in hydrogenated fats and many commercial products and fast foods). Choose unsaturated fats, particularly omega-3 fatty acids (found in vegetable and fish oils).
In selecting proteins, choose soy, legumes, poultry, and fish over meat. Fat free and low fat dairy products (skimmed milk, yogurt) are also healthy choices.
Controlling weight, quitting smoking, and exercising are essential companions of any diet program.

After starting any heart healthy diet, it generally takes an average of 3 - 6 months before any noticeable reduction in cholesterol occurs, although some people have reported better levels in as few as 4 weeks. An intensive program may be necessary to achieve significant improvements in cholesterol levels and to reduce other heart risk factors. [See In-Depth Report #43: Heart-healthy diet.]

Depression. Depression increases the severity of heart attack and may even impair a patient's response to medication for heart disease. Although people with heart disease may certainly become depressed, this does not explain entirely the link between the two problems. The data now suggest that depression itself may be a true risk factor for heart disease as well as its increased severity. Several studies have suggested that depression has biologic effects on the heart, including blood clotting and heart rate. A study in 2001, for example, reported an association between depression and a greater risk for death from heart problems even in people without a history of heart disease. A 2002 study reported a higher risk for heart failure in women -- although not in men -- with depression. The more severe the depression, the more dangerous to the health, although even mild depression, including feelings of hopelessness, experienced over many years, may harm the heart, even in people with no early signs of heart disease. [See In-Depth Report #8: Depression.]

Adverse Effects of Heavy Drinking on the Heart. By contrast, heavy drinking harms the heart; heart disease is the leading cause of death in alcoholics. Evidence suggests that people who consume more than three drinks a day have abnormal blood clotting factors. Heavy alcohol consumption can raise blood pressure, and binge drinking may increase the risk for hemorrhagic stroke (caused by bleeding in the brain). Large doses of alcohol can trigger irregular heartbeats, which can be dangerous in people with existing heart disease.

Pregnant women and people who can't drink moderately should not drink at all.

In 2005, the FDA warned that all nonsteroidal anti-inflammatory drugs (NSAIDs) -- with the exception of aspirin -- carry heart risks. NSAIDs and COX-2 inhibitors may increase the risk for death in patients who have experienced a heart attack. The risk is greatest at higher dosages, but not necessarily for length of time. According to a 2006 Danish study of heart attack survivors, patients do not need to take NSAIDs for long periods of time to be at risk.

NSAIDs include nonprescription drugs like ibuprofen (Advil, Motrin) and prescription drugs like diclofenac (Cataflam, Voltaren). Celecoxib (Celebrex) is currently the only COX-2 inhibitor that is available in the U.S. It has been linked to cardiovascular risks such as heart attack and stroke. Patients who have had heart attacks should talk to their doctors before taking any of these drugs.

A 2006 comprehensive report from the U.S. Agency for Healthcare Quality and Research indicated that both NSAIDs and COX-2 inhibitors pose similar risks for heart attacks. The report found that one particular NSAID, naproxen (Aleve, Naprosyn), may present less risk of heart attack for some patients, but other studies have contradicted this finding. A 2006 Journal of the American Medical Association study suggested that diclofenac (Voltaren, Cataflam) poses a higher risk for heart attack than other NSAIDs.

In 2007, the American Heart Association issued a scientific statement encouraging doctors to change the way they prescribe pain relief medication for patients with or who are at risk for heart disease. The AHA recommends that patients first try non-drug methods of pain relief (physical therapy, exercise, weight loss to reduce stress on joints, and heat or cold therapy). If these methods don’t work, patients should take the lowest possible dose of acetaminophen (Tylenol) or aspirin. COX-2 inhibitors, such as celecoxib (Celebrex), should be the last resort.

Anemia. Anemia has adverse effects on the heart and increases the severity of cardiac conditions, including heart failure and heart attacks.

Iron Overload. An inherited disease called hemochromatosis, in which the intestinal tract absorbs too much iron from food, has been associated with atherosclerosis and heart attack. About 10% of Caucasians carry the gene. There is no strong evidence that excess iron levels in people without hemochromatosis can contribute to heart disease.

Pregnancy Complications. Although women of child-bearing age are generally at low risk of heart attack, pregnancy can increase the risk for women with certain health conditions. Pregnant women who have diabetes, high blood pressure, or coronary artery disease are at greater risk of having a heart attack than healthy pregnant women. Smoking can increase the risk of heart attack during pregnancy by eight times. Pregnant women who are over 40 years old are at much greater risk than younger women.

Diagnosis

When a patient comes to the hospital with chest pain, the following diagnostic steps are usually taken to determine any heart problems, and, if present, their severity.

The patient will report all symptoms so that a health professional can rule out either a non-heart problem or possible other serious accompany conditions.
An electrocardiogram (ECG) reading is taken, which records the waves made the heart. It is the key tool for determining if heart problems are causing chest pain and, if so, how severe they are.
Blood tests showing elevated levels of certain factors (troponins and CK-MB) indicate heart damage. (The doctor will not wait for results, however, before administering treatment if a heart attack is strongly suspected.)
Imaging tests, including echocardiogram and perfusion scintigraphy, help rule out a heart attack if there is any question.

An electrocardiogram (ECG or EKG) measures and records the electrical activity of the heart. The waves measured by the ECG correspond to the contraction and relaxation pattern of the different parts of the heart. Specific waves seen on an ECG are named with letters:

P. The P wave is associated with the contractions of the atria (the two chambers in the heart that receive blood from outside).
QRS. The QRS is a series of waves associated with ventricular contractions. (The ventricles are two major pumping chambers in the heart.)
T and U. These waves follow the ventricular contractions.

Click the icon to see an image of a normal sinus rhythm.

Doctors use a term called the P-Q or P-R interval, which is the time taken for an electrical impulse to travel from the atria to the ventricle.

The most important wave patterns in diagnosing and determining treatment for a heart attack are called ST elevations and Q waves.

Elevated ST Segments: Heart Attack. Elevated ST segments are strong indicators of a heart attack in patients with symptoms and other indicators. They suggest that an artery to the heart is blocked and that the full thickness of the heart muscle is damaged. When this finding coincides with a heart attack, the condition is sometimes referred to as either as a Q-wave myocardial infarction or a STEMI (ST-segment elevation myocardial infarction). STEMI heart attacks are very severe and usually have complete artery blockage. ST-elevations are strong indicators for aggressive treatments (thrombolytic drugs or angioplasty) to reopen blood vessels. (ST segment elevations do not always mean the patient has a heart attack. Also, some patients do not have elevated ST segments. Other factors are important in making a diagnosis.)

Non-Elevated ST Segments: Angina and Acute Coronary Syndrome. A depressed or horizontal ST wave suggests some blockage and the presence of a heart disease, even if there is no angina present. It occurs in about half of patients with other signs of a heart event. This finding, however, is not very accurate, particularly in women, and can occur without heart problems. In such cases, laboratory tests are needed to determine the extent, if any, of heart damage. In general, one of the following conditions may be present:

Stable Angina (blood test results or other tests show no serious problems and chest pain resolves). Most patients with angina can go home. (Between 25 - 50% of people who have angina or silent ischemia have normal ECG readings.)
Acute Coronary Syndrome (ACS). This includes severe and sudden heart conditions that require aggressive treatment but have not developed into a full-blown heart attack. ACS, refers to either unstable angina or NSTEMI (non ST-segment elevation myocardial infarction) -- also referred to as non Q-wave myocardial infarction. Unstable angina is potentially serious, and chest pain is persistent, but blood tests do not show markers for heart attack. With NSTEMI, the blood tests suggest a developing heart attack, but most likely, injury in the arteries is less serious than with a full-blown heart attack.

Nuclear ventriculography (also known as a radionuclide test) uses radioactive materials called tracers to make heart chambers and blood vessels visible. The procedure is noninvasive. It is a reliable measure of severe heart events and can help identify if damage has occurred from a heart attack. A radioactive isotope such as thallium (or technetium) is injected into the patient's vein. The radioactive isotope attaches to red blood cells and passes through the heart in the circulating blood. The isotope can then be traced through the heart using special cameras or scanners. The images may be combined with an electrocardiogram. The patient is tested while resting, then tested again during an exercise stress test. If the scan detects damage, more images are taken 3 or 4 hours later. Damage due to a prior heart attack will persist when the heart scan is repeated. Injury caused by angina, however, will have resolved by that time.

Angiography is an invasive test. It is used for patients who show strong evidence for severe obstruction on stress and other tests and for patients with acute coronary syndrome.

A narrow tube is inserted into an artery, usually in the leg or arm, and then threaded up through the body to the coronary arteries.
A dye is injected into the tube, and an x-ray records the flow of dye through the arteries.
This process provides a map of the coronary circulation, revealing any blocked areas.

Click the icon to see an image of cardiac catheterization.

Click the icon to see an image of dye injected into the coronary arteries.

Tests that measure kidney function can help predict which patients are at greatest risk of heart attack, stroke, or death from heart disease. Kidney tests measure proteins in the blood that are filtered through the kidneys. These proteins include creatinine and blood urea nitrogen (BUN). A more recent type of kidney test measures the protein cystatin C. Recent research suggests that the cystatin C kidney test may be better at predicting cardiovascular risks in elderly patients.

When heart cells become damaged, they release different enzymes and other molecules into the blood stream. Elevated levels of such markers of heart damage in the blood or urine may help predict a heart attack in patients with severe chest pain and help determine treatment. Some markers include:

Troponins. The proteins cardiac troponin T and I are released when the heart muscle is damaged. Both are proving to be among the best diagnostic indications of heart attacks. They help to identify many individuals with ACS who might otherwise be misdiagnosed.
Creatine kinase myocardial band (CK-MB). CK-MB has been a standard marker, but the MB fraction is not as accurate as troponin levels, since elevated levels can appear in people without heart injury.
Myoglobin. Myoglobin is a protein found in heart muscles. It is released early in the injured heart and may be useful in combination with CK-MB and the troponins.
Newer biomarkers, including C-reactive protein (CRP), homocysteine, B-type natriuretic peptide (BNP), urinary albumin, and fibrinogen.

Several 2006 studies that evaluated how well biomarkers predict the risk of heart events concluded that they do not provide much more useful information than standard risk factors (high blood pressure, unhealthy cholesterol levels, diabetes). At this time, most experts feel that these standard disease risk factors provide the best predictors of the likelihood of developing coronary artery disease, heart attack, or stroke.

Treatment

Treatment options will depend on whether the patient has angina, acute coronary syndrome, or a full-blown heart attack.

Patients who are diagnosed with acute coronary syndrome (ACS) may be at risk for a heart attack. ACS refers to either unstable angina or NSTEMI (non ST-segment elevation myocardial infarction). Unstable angina is potentially serious and chest pain is persistent, but blood tests do not show markers for heart attack. With NSTEMI, the blood tests suggest a developing heart attack, but most likely, injury in the arteries is less serious than with a full-blown heart attack.

Doctors use a patient's medical history, various tests, and the presence of certain factors to help predict which ACS patients are most at risk for developing a more serious condition. The degree of chest pain itself is not necessarily useful for determining the actual damage in the heart.

Depending on how severe the condition is, the patient is then given either medical treatments or more invasive approaches, such as angioplasty. Some experts believe that even if patients with ACS are only given drug therapy, they should still be transferred to centers equipped for angioplasty.

Early supportive treatments are similar for patients who have ACS or those who have had a heart attack.

Oxygen. Oxygen is almost always administered right away, usually through a tube that enters through the nose. The patient is given aspirin if one was not taken at home.

Medications for Relieving Symptoms.

Nitroglycerin. Most patients will receive nitroglycerin after a heart attack, usually under the tongue. Nitroglycerin decreases blood pressure and dilates the blood vessels around the heart, increasing blood flow. Nitroglycerin may be given intravenously in certain cases (recurrent angina, congestive heart failure, or high blood pressure). Some evidence suggests that intravenous administration may help reduce long-term heart muscle changes that can occur after a heart attack. (Patients with very low blood pressure or severely slow heart rate will not receive nitroglycerin.)
Morphine. Morphine not only relieves pain and reduces anxiety but also dilates blood vessels, aiding the circulation of blood and oxygen to the heart. Morphine can decrease blood pressure and slow down the heart. In patients in which such effects may worsen their heart attacks, other drugs such as meperidine (Demerol) or nalbuphine (Nubain) may be used.

Anticlotting Medications. Appropriate anticlotting medications are started immediately in all patients.

Aspirin (antiplatelet drug) should be taken immediately after a heart attack. It can be either swallowed or chewed, but chewing provides more rapid benefit. If the patient has not taken an aspirin at home, it will be given at the hospital.
Clopidogrel (a stronger antiplatelet drug) is usually given along with other anticlotting drugs. It is sometimes used in place of aspirin.
Heparin (an anticoagulant) is usually given to moderate- to high-risk patients. Low-molecular weight heparin (LMWH), such as enoxaparin, is now recommended over standard heparin. Fondaparinux (Arixtra) is another type of blood thinner that is showing promise for treating patients with STEMI (ST-elevation myocardial infarction), a severe type of heart attack. Fondaparinux may also be better than enoxaparin for patients with acute coronary syndrome (ACS).
Glycoprotein IIb/IIIa inhibitors (antiplatelet drugs), most often tirofiban, are added for patients undergoing angioplasty. These drugs include tirofiban (Aggrastat) and abciximab (ReoPro). They are also beneficial for nonsurgical patients with ACS, notably NSTEMI (non ST-segment elevation myocardial infarction).

After a heart attack, clots form in the injured artery within 4 - 6 hours in 90% of patients. Opening a clotted artery as quickly as possible is the best approach to improving survival.

The standard medical and surgical solutions for opening arteries are:

Angioplasty, also called percutaneous coronary intervention (PCI), is standard procedure for opening the arteries. Coronary artery bypass graft (CABG) is sometimes used as an alternative to angioplasty. Angioplasty should be performed no later than 12 hours after a heart attack.
Thrombolytics are known as blood-clot-busting drugs and are the standard medications used to open the arteries. They are administered as soon as possible in centers where angioplasty is not available or in patients who are not good candidates for angioplasty.

The best candidates for either thrombolytic therapy or angioplasty are:

Adults younger than 75 years old with elevated ST segments or indications of bundle branch block (an ECG reading showing an interruption in the electrical pathway within the heart).
Patients whose symptoms occur within 12 hours of treatment.

Specific Candidates for Emergency Angioplasty. Most patients who meet the criteria for either thrombolytic drugs or angioplasty do better with angioplasty (although only in centers equipped to do this procedure).

Good candidates for angioplasty include:

Elderly patients (including those over age 75) who meet the criteria for both approaches tend to do better with angioplasty than thrombolytic therapy
Patients with diabetes who meet the criteria for both approaches
Patients under age 75 who go into shock, provided that angioplasty can be performed within 18 hours of shock (There is no advantage for patients over 75 who are in shock.)

As with thrombolytic treatments, angioplasty is most effective when performed within 12 hours of symptoms, and the sooner the better. Unfortunately not all communities have centers experienced in the procedure. The experience of the medical center's staff is critical for optimal benefits, and not all surgeons are experienced in angioplasty. However, the procedure is becoming increasingly available, and overall mortality rates are improving over time with angioplasty. Patients or their families should be sure their surgeon has performed at least 75 of these procedures and that the medical center has performed at least 200.

Specific Candidates or Non-Candidates for Thrombolytics. People who meet the criteria for either thrombolytics or angioplasty may benefit from thrombolytic drugs even if they have high-risk conditions such as diabetes, high systolic blood pressure less than 180 mm Hg, or a history of heart attack.

Several studies report that women do worse after thrombolytic therapy. Evidence indicates, however, that they are generally older and have more serious medical conditions when they seek treatment. One study also reported that women were given these drugs an average of 14 minutes later than men were. Women on thrombolytic therapy still do better than those not given these drugs. The bottom line is that thrombolytic therapy is life-saving, and appropriate candidates, regardless of age or gender, should not be denied this therapy.

Thrombolytics should be avoided or used with great caution in the following patients:

People older than age 75 -- a 2000 study suggested that their risk of death was 38% higher than patients in their age group who were not given therapy; a higher risk exists in such older patients even if they are otherwise healthy.
Patients with elevated ST segments whose symptoms have continued beyond 12 hours
Pregnant women
People who have experienced recent trauma (especially head injury) or invasive surgery
People with active peptic ulcers
Patients who have been given prolonged CPR
Current users of anticoagulants

Thrombolytics should not be used in the following patients:

Patients who have experienced any recent major bleeding
Patients with low ST segments
Patients with a history of stroke
Patients with uncontrolled high blood pressure

After a heart attack, the patient may need a number of different medications, depending on their risk factors for a future heart attack:

Beta-blockers reduce the oxygen demand of the heart by slowing the heart rate and lowering arterial pressure. They have been proven to help improve survival in patients who have had a heart attack.
Angiotensin converting enzyme (ACE) inhibitors should be given on the first day to all patients, unless there are medical reasons for not taking them.
Calcium channel blockers may provide relief in patients with unstable angina whose symptoms do not respond to nitrates and beta blockers. They are also useful for patients with Prinzmetal's angina.
Statins. Statins are important cholesterol lowering drugs that are beneficial for patients who have experienced a heart attack. They may also have heart-protective properties that go beyond lowering cholesterol.
Atropine. Atropine may be given for a very low heart rate (bradycardia) or signs of atrioventricular (AV) block, in which electric conduction of nerve impulses to specialized muscles in the heart is slowed or interrupted.

Severely ill patients, particularly those in cardiogenic shock (a dangerous condition that includes a drop in blood pressure and other abnormalities) or with heart failure, will be monitored closely and stabilized. Oxygen is administered, and fluids are given or replaced when it is appropriate to either increase or reduce blood pressure. Such patients may be given dopamine, dobutamine, or both. Other treatments depend on the specific condition.

Heart failure. Intravenous furosemide may be administered. Patients may also be given nitrates, and ACE inhibitors, unless they have a severe drop in blood pressure or other conditions that preclude them. Clot-busting drugs or angioplasty may be appropriate and life-saving in many of these patients, although heart failure patients are less likely to be given these treatments.

Cardiogenic Shock. A procedure called intra-aortic balloon counterpulsation (IABP) is proving to help these patients when used in combination with thrombolytic therapy. IABP involves inserting a catheter containing a balloon, which is inflated and deflated within the artery to boost blood pressure. Left ventricular assist devices and early angioplasty might be considered.

An important study published in 2006 in the Journal of the American Medical Association indicated that early surgical intervention is important for patients who have cardiogenic shock. The study found that patients who had angioplasty or bypass surgery within 6 hours of a heart attack complicated by shock had greatly improved odds for long-term survival compared to patients who received intensive medical therapy with clot-busting drugs.

An arrhythmia is a deviation from the heart's normal beating pattern caused when the heart muscle is deprived of oxygen and is a dangerous side effect of a heart attack. A very fast or slow rhythmic heart rate often occurs in patients who have had a heart attack, and is not usually a dangerous sign.

Premature beats or very fast arrhythmias called tachycardia, however, may be predictors of ventricular fibrillation. This is a lethal rhythm abnormality, in which the ventricles of the heart beat so rapidly that they do not actually contract but quiver ineffectually. The pumping action necessary to keep blood circulating is lost.

Preventing Ventricular Fibrillation. People who develop ventricular fibrillation do not always experience warning arrhythmias, and to date, there are no effective drugs for preventing arrhythmias during a heart attack.

Potassium and magnesium levels should be monitored and maintained.
Intravenous beta-blockers followed by oral administration of the drugs may help prevent arrhythmias in certain patients.

Treating Ventricular Fibrillation.

Defibrillators. Patients who develop ventricular arrhythmias are given electrical shocks with defibrillators to restore normal rhythms. Some studies suggest that implantable cardioverter-defibrillators (ICDs) may prevent further arrhythmias in heart attack survivors of these events who are at risk for further arrhythmias. Patients with ICDs should not take fish oil supplements, as they may increase the risk of ventricular fibrillation.
Antiarrhythmic Drugs. Antiarrhythmic drugs include lidocaine, procainamide, or amiodarone. Amiodarone or another antiarrhythmic drug may be used afterward to prevent future events.

Managing Other Arrhythmias. People with an arrhythmia called atrial fibrillation have a higher risk for stroke after a heart attack and should be treated with anticoagulants such as warfarin (Coumadin). Other rhythm disturbances called bradyarrhythmias (very slow rhythm disturbances) frequently develop in association with a heart attack and may be treated with atropine or pacemakers.

[For more information on atrial fibrillation, ICDs, and pacemakers see In-Depth Report #45: Stroke.]

Medications

Thrombolytic, also called clot-busting or fibrinolytic, drugs are now mainstays in the early treatment of many patients with heart attacks. These drugs dissolve the clot, or thrombus, responsible for causing artery blockage and heart-muscle tissue death.

The standard thrombolytic drugs are recombinant tissue plasminogen activators or rt-PAs. They include alteplase (Activase) and reteplase (Retavase). Both are similar in effectiveness, although reteplase is easier to administer. Tenecteplase (TNKase), a newer drug, can be delivered more rapidly than alteplase, and to date, survival rates are similar. Streptokinase (Kabikinase, Streptase) is sometimes used but is somewhat less effective that the others.

The sooner that thrombolytic drugs are given after a heart attack, the better. The benefits of thrombolytics are highest within the first 3 hours. They can still help if given within 12 hours of a heart attack.

A thrombolytic drug, such as alteplase or tenecteplase, is typically given by IV along with heparin, an anticoagulant drug. (Heparin, like aspirin, cannot destroy existing blood clots but can prevent clots from reforming after they are broken up.) Enoproxin, a form of heparin called low-molecular weight heparin, may be more beneficial than standard heparin.

Other anticlotting drugs are being tested in combination with thrombolytic drugs for emergency treatment following a severe heart attack. Several 2005 studies have indicated that the antiplatelet drug clopidogrel (Plavix) can help prevent arteries from reclosing, and a second heart attack, when given along with aspirin and thrombolytic drugs. The studies evaluated patients who received thrombolytic drugs for treatment of STEMI (severe heart attacks with complete artery blockage).

Hemorrhagic stroke, usually occurring during the first day, is the most serious complication of thrombolytic therapy, but fortunately it is rare. Streptokinase given without heparin poses the lowest risk (although it is also less effective than other regimens in restoring blood flow). In general, the mortality rate from bleeding is only 3 in 1,000 patients treated with thrombolytics, whereas 39 patients in 1,000 would die without these clot-busting drugs. Recent evidence suggests that the survival benefits of thrombolytic therapy, particularly in combination with aspirin, last for years.

Anti-platelet Drugs. These drugs prevent formation of blood platelets. Platelets are very small disc-shaped blood cells that are important for blood-clotting.

Aspirin. Aspirin is an antiplatelet drug. It is the most common anti-clotting drug and nearly anyone with heart disease is advised to take it daily in low dose.
Thienopyridines. Clopidogrel (Plavix) and ticlopidine (Ticlid) are thienopyridines, another type of anti-platelet drug.
Glycoprotein IIb/IIIa Inhibitors. These powerful blood-thinning drugs include abciximab (ReoPro), eptifibatide (Integrilin), tirofiban (Aggrastat), and lamifiban. They are administered intravenously in the hospital and are used with angioplasty and stent placement. They are proving to be helpful for ACS patients with NSTEMI (non ST-segment elevation myocardial infarction).

Anticoagulants. Anticoagulants thin blood. They include:

Heparin
Fondaparinux (Arixtra)
Warfarin (Coumadin)
Direct thrombin inhibitors such as argatroban (Novastan), danaparoid (Orgaran), and lepirudin (Refludan)

How Anti-Clotting Drugs Are Used For Heart Attacks. Unlike the thrombolytic (clot-busting) drugs, which are used to break up blood clots during a heart attack, anti-clotting drugs are used to prevent blood clots from forming in the first place. Such drugs are sometimes used along with thrombolytics, immediately after a heart attack, and also as on-going maintenance to prevent a heart attack.

Aspirin is given immediately, and heparin is usually started during or at the end of the thrombolytic infusion.
Clopidogrel (Plavix) is given along with aspirin, heparin, and thrombolytic (“clot busting”) drugs as emergency treatment following a heart attack and to prepare for angioplasty surgery. In 2006, the FDA approved clopidogrel for patients who have had a STEMI heart attack and who are not going to have angioplasty. Clopidogrel is also helpful for patients with acute coronary syndrome. A 2006 study suggested that clopidogrel plus aspirin may not work better than aspirin alone in preventing a first heart attack. However, many studies show that clopidogrel is an important treatment for patients who have already had a heart attack. Clopidogrel and aspirin may reduce the risk of a second heart attack by 30%. The combination of clopidogrel (or ticlopidine) and aspirin is essential for patients who have a drug-eluting stent. In 2007, the American Heart Association recommended that patients with drug-eluting stents take this drug combination for at least 1 year after the stent is inserted to reduce the risks of blood clots.

All of these drugs pose a risk for bleeding. [See In-Depth Report #03: Coronary artery disease.]

Beta-blockers reduce the oxygen demand of the heart by slowing the heart rate and lowering pressure in the arteries. They are effective for reducing deaths from heart disease. These drugs include propranolol (Inderal), carvedilol (Coreg), bisoprolol (Zebeta), acebutolol (Sectral), atenolol (Tenormin), labetalol (Normodyne, Trandate), metoprolol (Lopressor, Toprol-XL), and esmolol (Brevibloc).

Administration During a Heart Attack. The beta-blocker metoprolol is given through an IV within the first few hours of a heart attack to reduce the destruction of heart tissue. However, a study suggests that emergency intravenous use of metoprolol may increase the risk of cardiac shock.

Prevention After a Heart Attack. Beta-blockers taken by mouth are also used on a long-term basis (“maintenance therapy”) after a first heart attack to help prevent future heart attacks.

Side Effects. Beta-blocker side effects include fatigue, lethargy, vivid dreams and nightmares, depression, memory loss, and dizziness. They can lower HDL (“good”) cholesterol. Beta-blockers are categorized as non-selective or selective. Non-selective beta-blockers such as carvedilol and propranolol can narrow bronchial airways. These beta-blockers should not be used by patients with asthma, emphysema, or chronic bronchitis.

Patients should not abruptly stop taking these drugs. The sudden withdrawal of beta-blockers can rapidly increase heart rate and blood pressure. The doctor may want the patient to slowly decrease the dose before stopping completely.

In 2004, the National Cholesterol Education Program issued updated recommendations on how to control cholesterol levels. These guidelines emphasize that patients should lower their LDL (“bad”) cholesterol and recommend that more people take LDL-lowering medication. Lowering LDL cholesterol and raising HDL (“good”) cholesterol can significantly reduce the risk of heart disease. Several different types of drugs (statins, bile-acid binding resins, niacin, and fibrates) are used to treat cholesterol. [See In-Depth Report #23: Cholesterol.]

A 2006 review of studies indicated that early, intensive therapy with statins can help reduce the risk of death, unstable angina, and revascularization (surgery to restore blood flow) for patients with acute coronary syndrome. The review indicated that statins work best when they are prescribed within 14 days of hospitalization for acute coronary syndrome. The researchers found that the effect of statins began about 4 months after starting drug therapy and that benefits lasted up to 2 years.

The main safety concern with statins is an uncommon condition called myopathy, which can cause muscle and joint pain and possible muscle damage. Doctors will immediately stop statin therapy if myopathy occurs. Patients should talk to their doctor about any unusual muscle discomfort or weakness or if their urine becomes brown-colored. Statins can also affect the liver, particularly at higher doses, so patients taking these drugs should receive regular liver function tests.

Angiotensin converting enzyme (ACE) inhibitors are important drugs for treating patients who have had a heart attack, particularly for patients at risk for heart failure. These drugs are commonly used to treat hypertension and are recommended as first-line treatment for people with diabetes and kidney damage.

ACE inhibitors include captopril (Capoten), ramipril (Altace), enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), perindopril (Aceon), and lisinopril (Prinivil, Zestril).

Magnesium has blood-thinning properties and may help open blood vessels. It is important to correct any magnesium deficiencies in patients (such as those who are taking diuretics).

Flu Shots. Influenza vaccinations may help protect patients against another heart attack during flu season.

Antibiotics. Researchers have investigated antibiotics for treating patients with heart disease and past infection of the bacteria Chlamydia pneumoniae. Results from several large-scale clinical trials, published in 2003 in the Journal of the American Medical Association (JAMA) and presented in 2004 at the European Society of Cardiology annual meeting, suggest that antibiotic treatment provides no benefit in preventing heart attack or other cardiac events in patients with coronary artery disease. While it is still possible that C. pneumoniae may play a role in triggering inflammatory responses associated with ACS, antibiotic therapy is no longer considered appropriate for treatment or prevention of heart disease.

Stem Cell Therapy. Researchers are investigating whether infusions of adult stem cells can help improve outcomes in patients who have a heart attack. Results from three small trials, published in 2006 in the New England Journal of Medicine, suggested that stem cell therapy may have some benefits in improving heart function. None of the studies reported treatment complications. Research presented at the 2007 American College of Cardiology annual meeting discussed intravenous stem cell therapy with Provacel (a commercial stem cell preparation). In the small study, patients who received Provacel had fewer adverse events (such as arrhythmia) and improved heart, lung, and overall function compared to patients who received placebo. Patients in the study received a Provacel infusion within 10 days of having a heart attack.

Surgery

Percutaneous coronary intervention (PCI), also called angioplasty, and coronary artery bypass graft surgery are the standard operations for opening narrowed or blocked arteries. They are known as revascularization procedures.

Emergency angioplasty is the standard procedure for heart attacks. It should be performed within 12 hours of a heart attack. Clot-buster drugs can help prevent damage, but must be given with 1 hour of a heart attack.
Coronary bypass surgery is typically used as elective surgery for patients with blocked arteries. It may be used after a heart attack if angioplasty or thrombolytics fail or are not appropriate. It is usually not performed for a few days to allow recovery of the heart muscles.

Click the icon to see an illustrated series detailing a heart bypass surgery.

Percutaneous coronary intervention (PCI), also called angioplasty, involves procedures such as percutaneous transluminal coronary angioplasty (PTCA) that help open the blocked artery. A typical angioplasty procedure involves the following steps:

Click the icon to see an image of an angioplasty.

The cardiologist threads a narrow catheter (a tube) containing a fiber into the blocked vessel.
The cardiologist opens the blocked vessel using balloon angioplasty, in which a tiny deflated balloon is passed through the catheter to the vessel.
The balloon is inflated to compress the plaque against the walls of the artery, flattening it out so that blood can once again flow through the blood vessel freely.
The balloon is inflated to compress the plaque against the walls of the artery, flattening it out so that blood can once again flow through the blood vessel freely.
To keep the artery open afterwards, doctors use a device called a coronary stent, an expandable metal mesh tube that is implanted during angioplasty at the site of the blockage.
Once in place, the stent pushes against the wall of the artery to keep it open. Stenting is improving results in patients with heart attack who have emergency angioplasty. It also significantly prevents reclosure and reduces heart attack rates in patients with ACS.

Experts recommend that appropriate patients receive angioplasty and stenting within 90 minutes after having a heart attack and no later than 12 hours following an attack. Although some hospitals have been performing angioplasty and stenting for up to a month following a heart attack, a landmark 2006 study found that delayed surgical intervention is not helpful for most patients. The Occluded Artery Trial (OAT), published in the New England Journal of Medicine, reported that balloon angioplasty and stenting failed to prevent heart complications in patients who received the procedure 3 – 28 days after a heart attack. The trial compared angioplasty to medications (aspirin, ACE inhibitors, beta-blockers, statins, clopidogrel).

Experts are now recommending delayed angioplasty and stenting only for patients who are unstable or who continue to have chest pain following a heart attack. This procedure may also be appropriate for patients who cannot tolerate beta-blocker drugs, which are commonly prescribed to help improve survival after a heart attack.

Complications occur in about 10% of patients (about 80% within the first day). Serious side effects include heart attack and the need for additional surgery. Best results occur in hospital settings with experienced teams and backup. Women who have angioplasty after a heart attack have a higher risk of death than men.

Reclosure and Blockage During or Shortly after Angioplasty. Reclosure of the artery often occurs during or shortly after angioplasty. A number of anticlotting drugs are used to reduce this risk. Clopidogrel (Plavix) is often given along with aspirin and thrombolytic drugs (such as abciximab) in the days before angioplasty surgery, to help prevent heart attack or stroke following surgery. Research suggests that abciximab (ReoPro) is especially helpful for patients with acute coronary syndrome.

Prevention of Restenosis. Narrowing or reclosing of the artery (restenosis) occurs within a year of angioplasty in many angioplasty patients, often requiring a repeat operation. In restenosis, the narrowing of the artery is usually due to scarring, not blood clots. Drug-eluting stents, which are coated with sirolimus (Rapamune) or paclitaxel (Taxol), can help prevent restenosis. Several 2006 studies indicated that this type of stent may be better than a bare metal stent for patients who have experienced a STEMI heart attack. However, because drug-eluting stents reduce arterial tissue growth, they can increase the risks of blood clots.

In February 2007, the American Heart Association and other professional organization issued an extremely important joint advisory statement. The statement advises that all patients who have drug-eluting stents must continue to take aspirin and clopidogrel (or, rarely,) ticlopidine for at least 1 year after the stent is inserted to reduce the risk of blood clots. Clopidogrel and ticlopidine are thienopyridine drugs that, like aspirin, help prevent blood platelets from clumping together. It is very important that patients who have drug-eluting stents take both aspirin and a thienopyridine drug. If for some reason patients cannot take a thienopyridine drug, they should receive a bare metal stent instead of a drug-eluting stent. [See In-Depth Report #03: Coronary artery disease.]

Click the icon to see an illustrated series detailing balloon angioplasty.

Coronary artery bypass graft surgery (CABG) is the alternative elective procedure to angioplasty for opening blocked arteries in patients with severe angina, particularly those who have two or more blocked arteries. It is a very invasive procedure, however:

The chest is opened, and the blood is rerouted through a lung-heart machine.
The heart is stopped during the procedure.
Segments of veins or arteries taken from elsewhere in the patient's body are fashioned into grafts, which are used to reroute the blood. The blood vessel grafts are placed in front of and beyond the blocked arteries, so the blood flows through the new vessels around the blockage.

Mortality rates with this procedure after a heart attack are much higher (6%) than when it is used electively (1 - 2%). How or when it should be used after a heart attack, then, is controversial. A 2002 study attempted to determine which patients are at highest risk for poor results from CABG after a heart attack. The study found higher risks for women, patients over age 75, and those with heart failure or other severe heart problems.

Rehabilitation

Lifestyle measures, particularly dietary factors, are equally important in preventing heart attacks and must be strenuously adhered to.

Physical rehabilitation is extremely important after a heart attack. It has been associated with a 25% reduction in mortality rates at 3 years. Rehabilitation may include:

Leg exercises may start as early as the first day. The patient usually sits in a chair on the second day, and begins to walk on the second or third day.
Most patients undergo low-level exercise tolerance tests early in their recovery. One study suggests that exercise testing within 3 days after a relatively minor attack may allow patients to go home earlier.
After 8 - 12 weeks, many patients, even those with heart failure, benefit from supervised exercise programs. Health professionals should provide the patient with schedules for low-level aerobic home-activity. Strength (resistance) training is also important. Tai Chi, a Chinese martial art, appears to be very beneficial and safe for people after a heart attack. It should be noted that the risk for serious heart events during rehabilitation is very low.

Patients generally return to work in about 2 months, although timing can vary depending on the severity of the condition.

Sexual activity after a heart attack carries a very low risk and is believed to be safe, particularly in people who had exercised regularly before the attack. In any case, the feelings of intimacy and love that accompany healthy sex can help offset depression, a far greater risk for a future attack.

Major depression affects between 15 - 23% of patients with ACS or heart attacks. Many studies suggest that depression is a major predictor for increased mortality in both women and men. (One reason may be that depressed patients are less likely to comply with their heart medications.)

Psychotherapeutic techniques, especially cognitive behavioral therapies, are very helpful. Doctors have been reluctant to prescribe antidepressant drugs after ACS or a heart attack because older antidepressants tended to have adverse effects on the heart. Newer antidepressants may be safer. Studies on sertraline (Zoloft), one of the selective serotonin reuptake inhibitor (SSRI) antidepressants, have not reported harmful effects for patients who have had a heart attack. It is not yet clear if other SSRIs are equally safe and effective.

Resources

www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.acc.org -- American College of Cardiology
www.americanheart.org -- American Heart Association

References

Antman EM, Bennett JS, Daugherty A, Furberg C, Roberts H, Taubert KA. Use of nonsteroidal antiinflammatory drugs: an update for clinicians: a scientific statement from the American Heart Association. Circulation. 2007 Mar 27;115(12):1634-42. Epub 2007 Feb 26.

Assmus B, Honold J, Schachinger V, Britten MB, Fischer-Rasokat U, et al. Transcoronary transplantation of progenitor cells after myocardial infarction. N Engl J Med. 2006 Sep 21;355(12):1222-32.

Chou R, Helfland M, Peterson K, Dana T, Roberts C. Comparative Effectiveness and Safety of Analgesics for Osteoarthritis. Comparative Effectiveness Review No. 4. (Prepared by the Oregon Evidence-based Practice Center under Contract No. 290-02-0024.) Rockville, MD: Agency for Healthcare Quality and Research. September 2006.

Gislason GH, Jacobsen S, Rasmussen JN, Rasmussen S, Buch P, Friberg J, et al. Risk of death or reinfarction associated with the use of selectivecyclooxygenase-2 inhibitors and nonselective nonsteroidal antiinflammatory drugs after acute myocardial infarction. Circulation. 2006 Jun 27;113(25):2906-13. Epub 2006 Jun 19.

Hulten E, Jackson JL, Douglas K, George S, Villines TC. The effect of early, intensive statin therapy on acute coronary syndrome: a meta-analysis of randomized controlled trials. Arch Intern Med. 2006 Sep 25;166(17):1814-21.

Hochman JS, Lamas GA, Buller CE, Dzavik V, Reynolds HR, Abramsky SJ, et al. Coronary intervention for persistent occlusion after myocardial infarction. N Engl J Med. 2006 Dec 7;355(23):2395-407. Epub 2006 Nov 14.

Hochman JS, Sleeper LA, Webb JG, Dzavik V, Buller CE, Aylward P, et al. Early revascularization and long-term survival in cardiogenic shock complicating acute myocardial infarction. JAMA. 2006 Jun 7;295(21):2511-5.

Kearney PM, Baigent C, Godwin J, Halls H, Emberson JR, Patrono C. Do selective cyclo-oxygenase-2 inhibitors and traditional non-steroidal anti-inflammatory drugs increase the risk of atherothrombosis? Meta-analysis of randomised trials. BMJ. 2006 Jun 3;332(7553):1302-8.

Kostis WJ, Demissie K, Marcella SW, Shao YH, Wilson AC, Moreyra AE. Weekend versus weekday admission and mortality from myocardial infarction. N Engl J Med. 2007 Mar 15;356(11):1099-109.

Laarman GJ, Suttorp MJ, Dirksen MT, van Heerebeek L, Kiemeneij F, Slagboom T, et al. Paclitaxel-eluting versus uncoated stents in primary percutaneous coronary intervention. N Engl J Med. 2006 Sep 14;355(11):1105-13.

Lloyd-Jones DM, Liu K, Tian L, Greenland P. Narrative review: Assessment of C-reactive protein in risk prediction for cardiovascular disease. Ann Intern Med. 2006 Jul 4;145(1):35-42.

Lunde K, Solheim S, Aakhus S, Arnesen H, Abdelnoor M, Egeland T, et al. Intracoronary injection of mononuclear bone marrow cells in acute myocardial infarction. N Engl J Med. 2006 Sep 21;355(12):1199-209.

McGettigan P, Henry D. Cardiovascular risk and inhibition of cyclooxygenase: a systematic review of the observational studies of selective and nonselective inhibitors of cyclooxygenase2. JAMA. 2006 Oct 4;296(13):1633-44. Epub 2006 Sep 12.

Nicholls SJ, Tuzcu EM, Sipahi I, Grasso AW, Schoenhagen P, Hu T, et al. Statins, high-density lipoprotein cholesterol, and regression of coronary atherosclerosis. JAMA. 2007 Feb 7;297(5):499-508.

Schachinger V, Erbs S, Elsasser A, Haberbosch W, Hambrecht R, Holschermann H, et al. Intracoronary bone marrow-derived progenitor cells in acute myocardial infarction. N Engl J Med. 2006 Sep 21;355(12):1210-21.

Spaulding C, Henry P, Teiger E, Beatt K, Bramucci E, Carrie D, et al. Sirolimus-eluting versus uncoated stents in acute myocardial infarction. N Engl J Med. 2006 Sep 14;355(11):1093-104.

Spertus JA, Kettelkamp R, Vance C, Decker C, Jones PG, Rumsfeld JS, et al. Prevalence, predictors, and outcomes of premature discontinuation of thienopyridine therapy after drug-eluting stent placement: results from the PREMIER registry. Circulation. 2006 Jun 20;113(24):2803-9. Epub 2006 Jun 12.

Wang TJ, Gona P, Larson MG, Tofler GH, Levy D, Newton-Cheh C, et al. Multiple biomarkers for the prediction of first major cardiovascular events and death. N Engl J Med. 2006 Dec 21;355(25):2631-9.

Review Date:
4/16/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Cholesterol

FitSugar — Wed, 08 Oct 2008 17:34:59 -0700

In This Report

Highlights
Introduction
Cholesterol's Effect on the...
Cholesterol's Effect on the...
Risk Factors
Symptoms
Diagnosis
Lifestyle Changes
Treatment
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

New Guidelines for Children and Adolescents

In 2007, the American Heart Association (AHA) established new guidelines for assessing and treating high cholesterol in children and adolescents. According to the AHA’s scientific statement:

LDL (“bad") cholesterol goals for children should be 190 mg/dL or less for children without heart disease risk factors and 160 mg/dL or less for children with heart disease risk factors.
Children who are overweight or obese, as well as those with a family history of high cholesterol and heart disease, should get their cholesterol levels checked.
For overweight and obese children with cholesterol imbalances, diet changes and exercise should be tried before drug treatment. For children with cholesterol imbalances who have a family history of cholesterol and heart problems, statins are the best first-line drug therapy.

Herbs and Supplements

Garlic, whether raw or in supplement form, does not help lower LDL in patients with moderately high LDL levels, according to a 2007 Archives of Internal Medicine Study.
Policosanol, a dietary supplement derived from sugar cane, has no effect on cholesterol, indicates a 2006 Journal of the American Medical Association (JAMA) study.

Diet Plans

In a 2007 JAMA comparison study of four diet plans (Atkins, Ornish, Zone, and LEARN), the low-carbohydrate Atkins diet was best at raising HDL (“good cholesterol”) levels and lowering triglyceride levels, but did not affect LDL levels. The low-fat Ornish diet was best at lowering LDL levels.
The Mediterranean diet works better than a low-fat diet in quickly lowering cholesterol as well as blood pressure and blood sugar, suggests a 2006 Annals of Internal Medicine study.

Drug Research

In contrast to research findings released last year, rosuvastatin (Crestor) does not appear to reverse heart disease, according to a 2007 JAMA study. However, the statin drug did help slow the progression of arterial thickening.

Introduction

Lipids are the building blocks of the fats and fatty substances found in animals and plants. They are microscopic layered spheres of oil, which, in animals, are composed mainly of cholesterol, triglycerides, proteins (called lipoproteins), and phospholipids (molecules made up of phosphoric acid, fatty acids, and nitrogen). Lipids do not dissolve in water and are stored in the body to serve as sources of energy.

Cholesterol is a white, powdery substance that is found in all animal cells and in animal-based foods (not in plants). In spite of its bad press, cholesterol is an essential nutrient necessary for many functions, including:

Repairing cell membranes
Manufacturing vitamin D on the skin's surface
Producing hormones, such as estrogen and testosterone
Possibly helping cell connections in the brain that are important for learning and memory

Regardless of these benefits, when cholesterol levels rise in the blood, they can have dangerous consequences, depending on the type of cholesterol. Although the body acquires some cholesterol through diet, about two-thirds is manufactured in the liver, its production stimulated by saturated fat. Saturated fats are found in animal products, meat, and dairy products.

Saturated fats are found predominantly in animal products, such as meat and dairy products, and are strongly associated with higher cholesterol levels. Tropical oils -- such as palm, coconut, and coconut butter -- are also high in saturated fats.

Triglycerides are composed of fatty acid molecules. They are the basic chemicals contained in fats in both animals and plants.

Lipoproteins are protein spheres that transport cholesterol, triglyceride, or other lipid molecules through the bloodstream. Most of the information about the effects of cholesterol and triglyceride actually concerns lipoproteins.

Lipoproteins are categorized into five types according to size and density. They can be further defined by whether they carry cholesterol or triglycerides.

Cholesterol-Carrying Lipoproteins. These are the lipoproteins commonly referred to as cholesterol.

Low density lipoproteins (LDL). (Often called the "bad" cholesterol.)
High-density lipoproteins (HDL), the smallest and most dense. (Referred to as the "good" cholesterol.)

Triglyceride-Carrying Lipoproteins.

Intermediate density lipoproteins (IDL). They tend to carry triglycerides.
Very low density lipoproteins (VLDL). These tend to carry triglycerides.
Chylomicrons (largest in size and lowest in density).

Lipoprotein(a). Lipoprotein(a), or lp(a) has a size and density somewhere between LDL and HDL. The molecules carry a protein that may interfere with the body's ability to dissolve blood clots. Lipoprotein(a) is being investigated as a possible marker or cause of heart disease.

Remnant Lipoproteins. Remnant lipoproteins are byproducts of chylomicrons, very low-density lipoproteins (VLDL), or both. Some research indicates that high levels may be an important risk factor for coronary artery disease, particularly in patients who have otherwise normal cholesterol levels.

Reducing LDL and total cholesterol levels, while at the same time boosting HDL levels, can prevent heart attacks and death in all people (with or without heart disease). Reducing LDL is the primary goal of most cholesterol therapy.

Blood tests can easily measure both HDL and overall cholesterol levels. It is very difficult to measure LDL levels by themselves, but LDL levels can be reliably calculated by subtracting HDL and triglyceride levels from total cholesterol. The exact formula is:

LDL = TOTAL CHOLESTEROL - HDL - TRIGLYCERIDES/5.

In 2004, the National Cholesterol Education Program updated its clinical practice guidelines. The new recommendations set lower treatment goals for LDL levels based on a patient's risk factors for heart disease.

The risk factors include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)

Two or more of these risk factors increases by 20% the chance of having a heart attack within 10 years.

The LDL cholesterol level is one of the most important factors in determining whether a patient needs cholesterol therapy and whether the treatment is working properly. In particular, the new guidelines emphasize lower LDL levels and earlier treatment for people with coronary artery disease, or other forms of atherosclerosis, and diabetes.


Risk Level	Goal (d/L)	OptimalGoal(d/L)
Very High Risk	70	70
High Risk	100	70
Moderate Risk	130	100
Low Risk	160	130

The following chart summarizes all goals.


Total Cholesterol Goals	LDL Goals	HDL Goals	Triglyceride Goals
Less than 200 mg/dL is desirable. Between 200 and 239 is borderline. Over 240 is high.	70 mg/dL is the new goal for very high-risk patients (recent heart attack; current active or unstable cardiovascular or cerebrovascular disease; or two multiple risk factors as defined above.) Below 100 mg/dL is optimal for everyone. It should be the goal for high-risk people including those with existing heart disease, diabetes, or two or more risk factors for heart disease; 70 mg/dL is an optimal goal for these individuals. 130 mg/dL or below for people with two or more risk factors; 100 mg/dL is an optimal goal. 160 mg/dL or below for people at less risk (one or zero risk factors); 130 mg/dL is an optimal goal. Anything above 160 is high, with levels above 190 being very high. LDL levels over 190 require medication even with no other cardiac risk factors present.	Levels above 40 mg/dL are desirable; levels above 60 mg/dL are optimal.	Below 150 mg/dL is normal. 150 - 199 is borderline high. 200 - 499 is high. Over 500 is very high.
*Risk factors for heart disease include a family history of early heart problems before age 55 for men (before age 65 for women), smoking, high blood pressure, diabetes, being older (over 45 for men and 55 for women), and having HDL levels below 35 mg/dL. People with two or more of these risk factors may have a 10-year risk of heart attack that exceeds 20%, and may therefore need to aim for LDL levels of 100 mg/dL or below.

Although current guidelines as described in the table are extremely useful, they do have pitfalls. For example, the following cholesterol levels pose some dilemmas:

Low LDL levels (protective) accompanied by low HDL, high triglycerides, or both (harmful)
High total cholesterol (harmful) accompanied by high HDL (protective)

Would individuals with these cholesterol balances be at high risk or low risk for developing heart disease? To resolve this dilemma, experts have devised a calculation for a risk ratio by dividing the total cholesterol by either total HDL or LDL. It is not clear at this point which ratio is a better predictor of heart disease, although the HDL ratio may be superior. Using this ratio, the following results indicate better to worse outlook:

The ideal ratio is 3.5 or below.
A ratio of 4.5 carries an average risk.
Ratios of 5 or higher are potentially dangerous.

For example, if a person has a high total cholesterol of 280 mg/dL but a high HDL level of 70 mg/dL, the risk ratio is 4, which actually carries a lower than average risk. The use of this ratio may predict coronary artery disease more accurately than using total cholesterol levels alone. Still, the primary goal of lipid-lowering therapy is reducing LDL levels. Evidence strongly suggests that the lower the LDL levels, the lower the risk for heart disease.

Cholesterol's Effect on the Heart

Coronary artery disease, commonly known as heart disease, is the leading cause of death in the U.S. and was responsible for nearly 500,000 deaths in 2003.

Atherosclerosis is a common disorder of the arteries. Fat, cholesterol, and other substances collect in the walls of arteries. Larger accumulations are called atheromas or plaque and can damage artery walls and block blood flow. Severely restricted blood flow in the heart muscle leads to symptoms such as chest pain.

As many as half of these deaths were probably due to unhealthy cholesterol and lipid levels. Strong evidence points to LDL as the villain and HDL as a hero in the process. The role of other lipids, notably triglycerides, is not entirely clear.

Unhealthy cholesterol, particularly low-density lipoprotein (LDL), forms a fatty substance called plaque, which builds up on the arterial walls. Smaller plaques remain soft, but older, larger plaques tend to develop fibrous caps with calcium deposits.

Click the icon to see an image of the developmental process of atherosclerosis.

The long-term result is atherosclerosis, commonly called hardening of the arteries. The heart is endangered in two ways by this process:

Eventually these calcified and inelastic arteries become narrower (a condition known as stenosis). As this process continues, blood flow slows and prevents sufficient oxygen-rich blood from reaching the heart. This condition leads to angina (chest pain) and, in severe cases, to heart attack.

Click the icon to see an image of a heart attack.

Smaller unstable plaques may rupture, triggering the formation blood clots on their surface. The blood clots block the arteries and are important causes of heart attack.

This process is accelerated and enhanced by other risk factors, including high blood pressure, smoking, obesity, diabetes, and a sedentary life style. When more than one of these risk factors is present, the risk is compounded.

The effects of cholesterol on the heart may involve more than just the arteries. There is some evidence that unhealthy levels may affect the heart muscles and increase the risk for heart failure. High cholesterol levels may even reduce the protection that aspirin provides for people with heart disease.

On an encouraging note, mortality rates associated with coronary artery disease have declined dramatically during the past 30 years. Some experts estimate that about 30% of the decline is due to better cholesterol management and statin drugs.

Studies consistently report a higher risk for death from heart disease with high total cholesterol levels (200 mg/dL and higher). The higher the cholesterol, the greater the risk. One study reported that men with total cholesterol levels higher than 240 mg/dL had a risk nearly two to four times that of men whose cholesterol was below 200 mg/dL. On average, every time a person's cholesterol level drops by a point, the risk of heart disease drops by 2%.

The primary villain in the cholesterol story is low-density lipoprotein (LDL). In a major study, the lowest incidence in heart disease was found among people with the lowest LDL levels. Lowering LDL is the primary goal of cholesterol drug and lifestyle therapy.

Low-density lipoprotein (LDL) transports about 75% of the blood's cholesterol to the body's cells. It is normally harmless. However, if it is exposed to a process called oxidation, LDL can penetrate and interact dangerously with the walls of the artery, producing a harmful inflammatory response. Oxidation is a natural process in the body that occurs from chemical combinations with unstable molecules. These molecules are known as oxygen-free radicals or oxidants.

When LDL collects on arterial walls these oxidants are released from the wall membranes.
Oxidants are missing an electron and tend to bind with other molecules in the body, a process called oxidation.
When the oxidation process modifies LDL, it signals the immune system that a harmful molecule has appeared.

Inflammation and Plaque. In response to oxidized LDL, the body releases various immune factors aimed at protecting the damaged walls. Unfortunately, in excessive quantities they cause inflammation and promote further injury to the areas they target:

White blood cells and other factors gather and form a fatty substance called plaque. (Of interest in this process is an enzyme called lipoprotein-associated phospholipase A2, which binds to oxidized LDL. Studies report that this enzyme may play a major role in the release of plaque-forming inflammatory factors.)
Other immune factors also cause inflammation and injure the endothelium, the layer of cells that line blood vessels.

Click the icon to see an image of the cut section of an artery.

Immune factors that increase the risk for blood clots are also mobilized.
Oxidized LDL plays another dangerous role by reducing levels of nitric oxide, a chemical that helps relax the blood vessels and allow blood to flow freely.

High density lipoprotein (HDL) appears to benefit the body in two ways:

It removes cholesterol from the walls of the arteries and returns it to the liver.

Click the icon to see an image of the liver.

It helps prevent oxidation of LDL. HDL actually appears to have its own antioxidant properties.

HDL helps keep arteries open and reduces the risk for heart attack. High levels of high HDL (above 60 mg/dL) may be nearly as important for the heart as low levels of LDL. HDL levels below 40 mg/dL are considered to be harmful. In one study, for each 4 mg/dL decline in HDL levels there was a 10% increase in coronary artery disease.

Triglycerides are major troublemakers for the heart. They appear to interact with HDL cholesterol in such a way that HDL levels fall as triglyceride levels rise. Low HDL is known to be harmful to the heart.

The harmful imbalance of high triglycerides with low HDL levels is also associated with obesity (particularly around the abdomen), insulin resistance, and diabetes. Insulin is a hormone essential for regulating the storage and use of glucose (sugar) and amino acids (proteins) in the body. Insulin resistance occurs when there are normal levels of insulin but the body cannot use it. Insulin resistance increases the risk for developing type 2 diabetes, and it is also associated with metabolic syndrome. Both of these conditions increase the risk for heart disease.

Some evidence also suggests that high triglycerides pose other dangers, regardless of cholesterol levels. Triglycerides, for example, may be responsible for blood clots that form and block the arteries. High triglyceride levels are also associated with the inflammatory response -- the harmful effect of an overactive immune system that can cause considerable damage to cells and tissues, including the arteries.

Studies are finding an elevated risk for angina and first heart attacks in people with elevated levels of lipoprotein(a), also known as or lp(a). This lipoprotein falls somewhere between HDL and LDL in density and may have some properties that increase the risk for blood clots. Some experts suggest, however, that high levels of lp(a) may merely be markers of late-stage atherosclerosis, not a cause. Because concentrations of lipoprotein(a) are usually inherited, they do not respond to dietary or lifestyle changes. At this time, few experts recommend drug treatments to reduce lp(a) levels. Older women, but not men, appear to be at greater risk for high lp(a) levels and their consequences.

Cholesterol's Effect on the Brain

Having adequate levels of HDL may be the most important lipid-related factor for preventing ischemic stroke, a type of stroke caused by blockage of the carotid arteries that carry blood to the brain. HDL may even reduce the risk for hemorrhagic stroke, a less common type of stroke caused by bleeding in the brain that is associated with low overall cholesterol levels.

The build-up of plaque in the internal carotid artery may lead to narrowing and irregularity of the artery's lumen, preventing proper blood flow to the brain. More commonly, as the narrowing worsens, pieces of plaque in the internal carotid artery can break free, travel to the brain, and block blood vessels that supply blood to the brain. This leads to stroke, with possible paralysis or other deficits.

The effects of high total cholesterol and LDL levels on ischemic stroke are less clear. One study suggested that the risk for ischemic stroke increases when total cholesterol is above 280 mg/dL. A 2002 study suggested that high cholesterol poses a risk for stroke only when specific proteins associated with inflammation are present.

Evidence points to high cholesterol levels, along with high blood pressure and a family history of the disease, as independent risk factors for AD. A major research target for common factors between cholesterol levels and AD has been apolipoprotein E (ApoE). ApoE plays a role in the movement and distribution of cholesterol for repairing nerve cells during development and after injury. People who carry a variant of this gene (ApoE4) are at significantly higher risk for AD.

High cholesterol may pose a risk for Alzheimer's regardless of this genetic factor, however. Some studies report that cholesterol is important within the brain for cell communication and memory.

Risk Factors

About half of all American adults have total cholesterol levels over 200 mg/dL. Over 25% have been told by doctors that they have unhealthy levels. Total cholesterol levels have been declining over the last several decades, at least among middle-aged and older adults. This decline may be partly due to the increased use of statins and other lipid-lowering medications. However, total cholesterol levels are getting higher among younger adults (ages 25 – 34 years). The major risk factor for these high rates may be the Western lifestyle. The typical high-fat/low-fiber American diet coupled with sedentary habits is largely responsible for this unfortunate trend.

Men. Heart disease is the major cause of death in men. On average, men develop coronary artery disease 10 - 15 years earlier than women do and have a greater risk for dying of heart disease at a younger age. A 2006 study suggested that high total cholesterol may also contribute to the development of high blood pressure in men.

Women. Coronary artery disease is also the number one killer of women. Women between the ages of 20 and 34, and after menopause (around age 55), have higher cholesterol levels than men. Some evidence suggests that HDL levels may be more significant in women than in men. In one study, at total cholesterol levels above 200, women with HDL levels below 50 had a higher death rate than those with levels above 50, regardless of their LDL cholesterol levels. Women also appear to be more susceptible to the high-triglyceride low-HDL syndrome, which may be a particular risk factor for heart disease.

Children and Adolescents. Children who have abnormal cholesterol levels are at increased risk of developing heart disease later in life. However, it is difficult to distinguish “normal” cholesterol levels in children. Changes in cholesterol levels occur between the ages of 8 - 18, and vary between genders and population groups. Cholesterol levels tend to naturally rise sharply until puberty, then decrease sharply, and then rise again.

In 2007, the American Heart Association established general LDL goals for children that take into account these fluctuations. The association’s LDL goals are 190 mg/dL or less for children with no additional heart disease risk factors and 160 mg/dL or less for children with additional risk factors (such as family history of high cholesterol, heart disease, and diabetes).

It is also clear that children who are overweight are at higher risk for high triglycerides and low HDL, which may be directly related to later unhealthy cholesterol levels. Studies have confirmed that childhood LDL levels and body-mass index (BMI) are strongly associated with cardiovascular risk during adulthood. The American Heart Association recommends that children who are overweight and obese, as well as those with a family history of high cholesterol, undergo cholesterol screening. Overweight and obese children who have high cholesterol should also get tested for high blood pressure, diabetes, and other conditions associated with metabolic syndrome.

As in adults, the primary source of unhealthy cholesterol levels in children comes from diets high in unhealthy fats: Saturated fats (found mainly in animal and dairy products) and trans fatty acids (found in commercial food products). Over-consumption of unhealthy fats increases the risk for both obesity and heart disease.

Less common causes of unhealthy cholesterol levels in children include:

Low-birth weight (associated with low HDL levels)
Low thyroid levels (hypothyroidism)
Kidney or liver diseases
Homozygous familial hypercholesterolemia. This is an uncommon inherited condition that causes severe cholesterol imbalances and can result in very early heart disease.
Certain medications such as specific antiseizure drugs, corticosteroids, and isotretinoin (Accutane)

Young and Middle-Aged Adults. The strongest evidence of unhealthy cholesterol levels and heart disease is in adults over age 45. However, a 2006 analysis found that while total cholesterol levels are decreasing among older adults, they are increasing in those age 25 - 34 years. Research strongly suggests that the younger a person is when unhealthy cholesterol levels develop, the greater the chance for serious heart and blood vessel problems in the future. A 2006 study in the New England Journal of Medicine indicated that keeping LDL levels low from an early age can help prevent heart disease later in life. In one important study, young men (ages 16 - 34) who had cholesterol levels at or above 240 mg/dL had two to four times the risk of dying from heart attack or other cardiac problems than did men whose cholesterol was lower than 200 mg/dL. Young men without cholesterol problems had a higher life expectancy, by up to 8 years. Other studies have suggested similar risks from unhealthy cholesterol in young women as well.

Elderly Adults. About 85% of people who die from coronary artery disease are over the age of 65. Because high cholesterol is an important risk factor for heart disease, experts strongly recommend statin or other lipid-lowering therapy for elderly people with high cholesterol levels. Surveys indicate that total cholesterol levels have been declining in older people over the last few decades. Many experts believe this is due in part to increased use of statin drugs.

In the U.S., obesity is at epidemic levels in all age groups. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, obese individuals tend to have high triglyceride levels and low HDL levels. This combination is a risk factor for heart disease. Obesity also causes other effects (high blood pressure, increase in inflammation) that pose major risks to the heart.

Obesity is a particularly hazard when it is one of the components of the metabolic syndrome, formerly known as syndrome X. This syndrome consists of obesity marked by abdominal fat, unhealthy cholesterol levels, high blood pressure, and insulin resistance. Metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. A 2002 study estimated that 24% of the population now has this condition. Many experts recommend that patients with metabolic syndrome should be aggressively treated with high-dose statin therapy to lower LDL levels.

Obesity is also strongly associated with type 2 diabetes, which itself poses a significant risk for high cholesterol levels and heart disease.

Low thyroid levels (hypothyroidism) are associated with unhealthy lipid levels. (Lipids are fat molecules). Specifically, people with hypothyroidism are at higher risk for high total and LDL cholesterol, triglycerides, and other lipids associated with heart disease. Treating the thyroid condition can significantly reduce cholesterol levels. Some experts suggest that patients with high cholesterol should be evaluated for thyroid function before they are given cholesterol-lowering drugs. Research is mixed on whether mild hypothyroidism (subclinical hypothyroidism) is associated with unhealthy cholesterol levels. [See In-Depth Report #38: Hypothyroidism.]

Hypothyroidism is a decreased activity of the thyroid gland which may affect all body functions. In this condition, the rate of metabolism slows, causing mental and physical sluggishness. The most severe form of hypothyroidism is myxedema, which is a medical emergency.

Genetics play a major role in determining a person's blood cholesterol levels. Children from families with a history of premature heart disease should be tested for cholesterol levels after they are 2 years old. Genes may influence whether a person has low HDL levels, high LDL levels, high triglycerides, or high levels of other lipoproteins, such as lipoprotein(a).

Some inherited disorders and genetic abnormalities have been identified:

Familial hypercholesterolemia causes dangerous increases in cholesterol. It may be more common than previously thought. One European study reported familial hypercholesterolemia in 1 out of every 400 people.
Familial lipoprotein lipase deficiency is a very rare disorder that causes depletion of lipoprotein lipase. This is an enzyme that appears to be important in the removal of lipoproteins that are rich in triglycerides. People who are deficient in it have high levels of cholesterol and fat in their blood. A very low-fat diet is essential and is an effective treatment for these individuals.
Several studies have found a genetic mutation affecting neuropeptide Y in people with high total cholesterol and LDL levels. Neuropeptide Y is a compound in the brain that regulates appetite.
Researchers have identified a gene called APOAV, which may help detect patients at risk for elevated levels of triglycerides.

Other medical conditions strongly associated with unhealthy cholesterol levels include:

Polycystic ovarian syndrome. Women with this disorder, particularly those who are obese, appear to be at increased risk for high triglyceride and low HDL levels. This risk may be due to higher levels of the male hormone testosterone in these women.

Click the icon to see an image of a polycystic ovary.

Kidney disease

Symptoms

There are no warning signs for high LDL cholesterol levels. When symptoms finally occur, they usually take the form of angina or heart attack in response to the buildup of atherosclerotic plaque in the patient's arteries. This is definitely a condition where it pays to invest in preventive medicine before dangerous complications occur.

Diagnosis

A blood test for cholesterol should include the entire lipoprotein profile: LDL, total cholesterol, HDL, and triglycerides. It is very difficult to measure LDL levels by themselves, but LDL levels can be reliably calculated using total cholesterol and HDL levels.

To obtain a reliable cholesterol reading, experts advise:

Avoid strenuous exercise for 24 hours before the test.
Do not eat or drink anything but water for 12 hours beforehand.
If the test results are abnormal, a second test should be performed between 1 week and 2 months after the first test.

Home Tests. Tests are available for home use and in public locations, such as shopping malls and pharmacies. For example, the CholesTrak Test can be taken at home with results in 10 minutes, but it measures only total cholesterol. The BioSafe Cholesterol Panel Test is also a home test, but it needs to be sent to a laboratory. This test, however, is very accurate and provides a full lipid profile.

Certain blood tests for factors associated with inflammation in the arteries indicate a higher risk for heart disease, even in people without unhealthy lipids:

C-reactive protein (CRP). CRP is regulated by a very potent immune factor called interleukin-6. Elevated levels have been strongly associated with the inflammatory response and a higher risk for heart attack, even in people with normal cholesterol levels. CRP is also associated with high blood pressure, insulin resistance (the primary problem in type 2 diabetes), and obesity.
A high white blood cell count.
Elevated fibrinogen (a factor responsible for blood clotting).
Lipoprotein-associated phospholipase A2 may prove to be another marker for inflammation and heart disease. Studies suggest that it may play some causal role in coronary artery disease.

A new type of test measures cholesterol levels in the skin. High skin levels may indicate an increased risk for atherosclerosis and serious heart disease.

General Screening Recommendations. Experts groups differ slightly on when screening should start, but the following are generally accepted recommendations:

Periodic cholesterol testing in all adults starting at age 20. Adults with normal cholesterol levels do not need to have the test repeated for 5 years unless changes occur in lifestyle (including weight gain and diet). Adults with risk factors for heart disease or stroke should be rechecked every 2 years.
Selective screening of children who are at risk for high cholesterol and heart disease or familial hypercholesterolemia, which is genetically elevated cholesterol. Risk factors include having parents with total cholesterol levels greater than 240, or having a parent or grandparent who had symptomatic heart disease at age 55 or younger.
Patients already being treated for high cholesterol should be checked every 2 - 6 months.

Lifestyle Changes

Although most studies that prove that lowering cholesterol saves lives are done using drug therapy, the absolute mandate for improving cholesterol levels is to first make changes in lifestyle (both diet and exercise). Even when drugs are used, healthy diet and physical activity are critical companions.

Although there are many major dietary approaches for protecting health, experts generally agree on the following recommendations for heart protection:·

Choose fiber-rich food (whole grains, legumes, nuts) as the main source of carbohydrates, along with a high intake of fresh fruits and vegetables. Walnuts in particular have cholesterol-lowering properties and are a good source of antioxidants and alpha-linolenic acid.
Avoid saturated fats (found mostly in animal products) and trans fatty acids (found in hydrogenated fats and many commercial products and fast foods). Choose unsaturated fats (particularly omega-3 fatty acids found in vegetable and fish oils).
In selecting proteins, choose soy protein, poultry, and fish over meat. A 2006 study found that soy does not help improve cholesterol. However, experts still recommend it as a heart healthy food choice.
Controlling weight, quitting smoking, and exercising are essential companions of any diet program.

After embarking on any heart healthy diet, it generally takes an average of 3 - 6 months before any noticeable reduction in cholesterol occurs. However, some people see improved levels in as few as 4 weeks. An intensive program may be necessary to achieve significant improvements in cholesterol levels and to reduce heart risk factors.

Therapeutic Lifestyle Changes (TLC) from the National Cholesterol Education Program. Guidelines from the National Cholesterol Education Program include these recommendations for preventing and managing high cholesterol levels in adults:

Choose five or more servings of fresh fruits and vegetables and six or more servings of whole grains, legumes. Soluble fiber is preferred (from cereal grains, beans, peas, legumes, and many fruits and vegetables).
Fats can be up to 35% of daily calories, but no more than 7% should be from saturated fat. (People with high triglycerides, low HDL, or both may need a higher fat intake.) Choose fats containing unsaturated fatty acids (from vegetables, fish, legumes, and nuts). Choose margarines containing sterols or stanols (Benecol, Take Control). Avoid trans fatty acids found in commercial baked products.
Protein choices should be fat-free and low-fat milk products, fish, legumes, skinless poultry, and lean meats.
Limit dietary cholesterol intake to less than 200 mg per day.
Maintain healthy body weight and a healthy level of physical fitness.

Mediterranean Diet. The Mediterranean diet is rich in heart-healthy fiber and nutrients, including omega-3 fatty acids and antioxidants. The diet consists of fruits, vegetables, and unsaturated “good” fats, particularly olive oil. Olive oil has been associated with lower blood pressure, a lower risk for heart disease, and possible benefits for people with type 2 diabetes. Olive oil also contains polyphenol, which are phytochemicals that may help boost HDL levels.

A 2006 study that compared several types of Mediterranean diets to a low-fat diet found that Mediterranean diets were better at lowering blood pressure, cholesterol levels, and blood sugar levels after only 3 months. And, in research presented at the 2007 American College of Cardiology annual conference, the Mediterranean diet proved just as good as the American Heart Association low-fat diet for preventing recurrence of heart attack, stroke, or other heart events.

There are several variations to the Mediterranean diet but general recommendations include:

Limit red meats.
Drink one or two glasses of wine each day if alcohol is enjoyable and there are no reasons to restrict its use.
Limit dairy products.
Eat moderate amounts of fish and poultry. Fish is the diet’s main protein source. Some studies suggest that fish is the primary heart-protective ingredient in this diet.
Eat plenty of fresh fruits and vegetables, nuts, legumes, beans, and whole grains.
Season with garlic, onions, and herbs. Unfortunately, garlic does not appear to help lower cholesterol, but it may have other heart benefits. [See Herbs and Supplements in this section.]

Low-Carbohydrate Diets. The Atkins, South Beach, The Zone, and other diet restrict carbohydrate intake include. A 2006 review of low-carbohydrate diets found that they did help weight loss in the short term. However, while these diets appeared to lower triglyceride and raise HDL (“good”) cholesterol levels, they also raised overall and LDL (“bad”) cholesterol levels.

In contrast, a 2007 Journal of the American Medical Association study that compared four different low-carbohydrate and low-fat diet plans (Atkins, Zone, Ornish, and LEARN) found that the Atkins diet was best at raising HDL levels and reducing triglyciderides. In terms of LDL reduction, the low-fat Ornish diet produced the best improvements while the Atkins diet had no effect on LDL. The Atkins diet did result in better moderate weight loss (an average of 10 pounds over the course of a year versus 4 - 6 pounds for the other diet plans), which in itself may have accounted for the improved heart risk factors.

Glycemic Index. Low-carb diets -- such as South Beach, The Zone, and Sugar Busters -- rely on a concept called the "glycemic index," or GI, which ranks foods by how fast and how high they cause blood sugar levels to rise. Foods on the lowest end of the index take longer to digest. Slow digestion wards off hunger pains. It also helps stabilize insulin levels. Foods high on the glycemic index include bread, white potatoes, and pasta while low-glycemic foods include whole grains, fruit, lentils, and soybeans. (These low-glycemic foods are also important components of low-fat diet plans.) A 2006 study indicated that a high-protein, low-glycemic index diet can help produce better reductions in total and LDL cholesterol than a high-protein, high-glycemic index diet. Reducing glycemic load may also help to promote weight loss, especially for women.

Low Fat Diets. Dietary guidelines recommend keeping total fat intake to 20 - 30% of total daily calories, with saturated fat less than 10% of calories. Low-fat diets generally restrict fat intake to 20% or less of total daily calories. The Ornish program, which is recommended for some heart disease patients, limits fats even more drastically. It aims at reducing saturated fats as much as possible, restricting total fat to 10%, and increasing carbohydrates to 75% of calories. In 2006, the largest study to date on low-fat diets found that they did not help prevent heart disease or cancer. Women in the study reduced their fat consumption to 24 - 29% of total daily calories. Some critics say that the study did not do enough to distinguish between good types of fats (monounsaturated omega-3 polyunsaturated) and bad fats (saturated and trans fats).

The DASH Diet. The DASH diet (Dietary Approaches to Stop Hypertension) is proven to help lower blood pressure. Results are sometimes seen within a few weeks. Restricting sodium improves results. The diet appears to have antioxidant effects and may help lower LDL cholesterol levels, although beneficial HDL levels also decline. This diet is not only rich in important nutrients and fiber but also includes foods that contain far more electrolytes, potassium (4,700 mg/day), calcium (1,250 mg/day), and magnesium (500 mg/day) than are found in the average American diet.

A diet that is effective in lowering blood pressure is called Dietary Approaches to Stop Hypertension (DASH).

The DASH diet recommends:

Limit salt intake to no more than 2,300 mg a day (a maximum intake of 1,500 mg a day is an even better goal).
Reduce saturated fat to no more than 6% of daily calories and total fat to 27% of daily calories. (But, include dairy products that are non- or low-fat. Low-fat dairy products appear to be especially beneficial for lowering systolic blood pressure).
When choosing fats, select monounsaturated oils, such as olive or canola oils.
Choose whole grains over white flour or pasta products.
Choose fresh fruits and vegetables every day. Many of these foods are rich in potassium, fiber, or both which may help lower blood pressure.
Include nuts, seeds, or legumes (dried beans or peas) daily.
Choose modest amounts of protein (no more than 18% of total daily calories). Fish, skinless poultry, and soy products are the best protein sources.
Other daily nutrient goals in the DASH diet include limiting carbohydrates to 55% of daily calories and dietary cholesterol to 150 mg. Patients should try to get at least 30 g of daily fiber.

Slight changes to the DASH diet might help lower blood pressure even more, as well as improve cholesterol and lipid levels. Researchers reporting in the Journal of the American Medical Association and at the 2005 American Heart Association meeting said that replacing some carbohydrates in the DASH diet with more protein (from mostly plant sources) or monounsaturated fats may help reduce heart disease risk factors.

Calorie Restriction. Calorie restriction has been the cornerstone of weight-loss programs. Restricting calories in such cases also appears to have beneficial effects on cholesterol levels, including reducing LDL and triglycerides and increasing HDL levels. At this point, reducing calories and increasing exercise is still the best method for maintaining weight loss and preventing serious conditions, notably diabetes. A 2006 study reported that a low-calorie, but nutritionally balanced diet can help prevent an aging-associated change in heart function. Patients in the small study took in 1,400 - 2,000 calories a day for an average of 6 years.

The standard dietary recommendations for losing weight are the following:

As a rough rule of thumb, one pound of fat equals about 3,500 calories, so one could lose a pound a week by reducing daily caloric intake by about 500 calories a day. Naturally, the more severe the daily calorie restriction, the faster the weight loss.
To determine the daily calorie requirements for specific individuals, multiply the number of pounds of ideal weight by 12 - 15 calories. The number of calories per pound depends on gender, age, and activity levels. For instance, a 50-year-old moderately active woman who wants to maintain a weight of 135 pounds might require only 12 calories per pound (1,620 calories a day). A 25-year-old female athlete who wants to maintain the same weight might require 25 calories per pound 2,025 (calories a day).

Fat intake should be no more than 30% of total calories. Most fats should be in the form of monounsaturated fats (such as olive oil). Saturated fats (found in animal products) should be avoided.

Inactivity is one of the four major risk factors for coronary artery disease, on par with smoking, unhealthy cholesterol, and high blood pressure. In fact, studies suggest that people who change their diet in order to control cholesterol only achieve a lower risk for heart disease when they also follow a regular aerobic exercise program.

People who maintain an active lifestyle have a 45% lower risk of developing heart disease than sedentary people. Even moderate exercise reduces the risk of heart attack. One study of women found that just 1 hour of walking a week was associated with a lower risk for heart disease. The effects were similar even in women at high risk for developing heart disease.
Some studies suggest that for the greatest heart protection, it is not the duration of a single exercise session that counts but the total daily amount of energy expended. Therefore, the best way to exercise may be in multiple short bouts of intense exercise.
Burning at least 250 calories a day (the equivalent of about 45 minutes of brisk walking or 25 minutes of jogging) seems to offer the greatest protection against coronary artery disease, most likely because it raises HDL ("good cholesterol") levels. Moderate exercise has little effect on HDL.
Aerobic exercise helps to open up blood vessels and, in combination with a healthy diet, may improve blood-clotting factors.
Resistance (weight) training offers a complementary benefit to aerobics by reducing LDL ("bad cholesterol") levels.
Exercises that train and strengthen the chest muscles may prove to be very important for patients with angina.

Cigarette smoking lowers HDL and is directly responsible for approximately 20% of all deaths from heart disease. The importance of breaking this habit cannot be emphasized enough. Once a person quits smoking, HDL cholesterol levels rise within weeks or months to levels that are equal to their nonsmoking peers. Passive smoking also reduces HDL levels in people exposed to cigarette smoke.

A number of studies have found heart protection from moderate intake of alcohol (one or two glasses a day). Moderate amounts of alcohol help raise HDL levels. Although red wine is most often cited for healthful properties, any type of alcoholic beverage appears to have similar benefit. Pregnant women, anyone who cannot drink moderately, and people with liver disease should not drink at all.

Manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.

The following natural remedies are of interest for cholesterol control:

Garlic. Contrary to popular belief, garlic does not significantly reduce cholesterol, according to a 2007 Archives of Internal Medicine study. Researchers tested raw garlic and two types of garlic supplements in 192 patients with moderately high LDL levels. None of the forms of garlic had any effect on LDL levels. However, the researchers note that garlic may still help people with very high LDL levels and it may contain other heart-protective properties.

Policosonol. Policosanol is a nutritional supplement derived from sugar cane that has been promoted as having lipid-lowering benefits. In a randomized, placebo-controlled trial published in 2007 in the Archives of Internal Medicine, policosanol was no better than placebo in reducing LDL levels.

Treatment

In 2004, the National Cholesterol Education Program issued its latest recommendations for cholesterol control and management. These guidelines increase the number of Americans who should be taking LDL-lowering medication.

Starting Medications. Even modest lowering of high cholesterol levels, whether through drug therapy or lifestyle changes, reduces the risk of disability and death from heart disease. Most experts now focus on lowering LDL ("bad") cholesterol. Reducing LDL levels is particularly critical for patients with diabetes.

The doctor will start or consider medication when:

LDL cholesterol is 190 mg/dL or higher.
LDL cholesterol is 160 mg/dL or higher AND patient has one risk factor for heart disease.
LDL cholesterol is 130 mg/dL or higher AND patient has either diabetes or two other risk factors for heart disease.
LDL cholesterol is 100 mg/dL or higher AND patient has heart disease. (If patient has diabetes, even without heart disease, medication may be considered for an LDL cholesterol of 100 mg/dL.)
LDL cholesterol is greater than 70 mg/dL AND patient has had a recent heart attack or has known heart disease along with diabetes, current cigarette smoking, poorly controlled high blood pressure, or the metabolic syndrome (high triglycerides, low HDL, and obesity).

Risk factors for heart disease include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)

Recent studies have found that aggressive lipid lowering with high-dose statin therapy is more beneficial than standard statin therapy in patients with existing heart disease. The Pravastatin or Atorvastatin Evaluation and Infection Trial (PROVE-IT) and the Reversal of Atherosclerosis with Aggressive Lipid-Lowering trial (REVERSAL) compared the benefits of standard statin therapy (pravastatin, 40 mg) with intensive statin therapy (atorvastatin, 80 mg) in treating patients with heart disease.

Results from PROVE-IT demonstrated that for high-risk patients, intensive statin therapy is more effective than standard therapy in lowering LDL cholesterol and C-reactive protein (CRP) levels, and that CRP levels predict risk even when LDL cholesterol has been lowered substantially. The REVERSAL data suggest that intensive statin therapy produces greater reductions in LDL and CRP levels, and that the more that statins can lower LDL, the more effective they are in reducing the progression of atherosclerosis.

An important 2006 study found that aggressive treatment with rosuvastatin (Crestor):

Helped lower LDL to below guideline levels
Moderately increased HDL levels
Reduced fatty plaque in the arteries

Experts hoped that these results suggested that statin therapy might have the potential to reverse coronary atherosclerosis. However, a follow-up 2007 study of rosuvastatin indicated that while the drug slowed the rate of atherosclerotic progression, it did not reverse heart disease. Future studies will continue to investigate this issue and to explore whether other statins have a similar positive effect on coronary artery disease. Rosuvastatin lowers LDL more than other statins, but it also carries greater risks for more serious side effects (see Adverse Effects section). Many experts believe that the more that LDL is reduced through statin therapy, the greater the reduction in risk for heart disease, heart attack, and stroke.

It is important to emphasize that cholesterol-lowering medications are used along with healthy lifestyle habits, not in place of them.

Choosing the Correct Lipid-Lowering Medication. Experts now recommend that drug treatments be tailored for raising or lowering specific lipids, depending on the patient's blood lipid picture:

Statins are now the standard drugs for most people who require LDL-lowering therapy. Bile-acid binding resins or niacin may be considered. If LDL goals are not achieved, combinations of a statin with a bile-acid resin or niacin should be considered.
Fibrates or niacin are beneficial for people who need to lower triglycerides and increase HDL.

Considerations for Children and Adolescents. In 2007, the American Heart Association (AHA) issued a scientific statement addressing the use of cholesterol drugs in children and adolescents. The AHA recommends that for children who are overweight or obese, lifestyle modifications (diet, exercise) are preferred over drug therapy and should be the first step in lowering cholesterol.

For children and adolescents who have high-risk cholesterol imbalances -- and have a family history of high cholesterol, heart attack, stroke, and diabetes -- the AHA now recommends statins as the first-line drug therapy.

Considerations for People with Diabetes. At this time, statins are recommended as the best drugs for improving cholesterol and lipid levels in people with diabetes. Studies suggest that they can reduce the risk for adverse heart events in people with diabetes, even if their cholesterol levels are normal or if their diabetes is mild. Furthermore, in one study, a statin was shown to reduce the risk of developing diabetes by 30% in people with high cholesterol. Fibrates may also be useful for people with type 2 diabetes. Niacin (nicotinic acid) has the best effect on the cholesterol profile of people with diabetes but it also increases blood sugar levels. One well-controlled study, however, found that people with diabetes who used niacin had little trouble with glucose control, and some experts believe it now may be used as an alternative to or in combination with statins.


	Effect on High LDL	Effect on Low HDL	Effect on High Triglycerides	Effect on Lp(a)
Statins	Decrease (18 - 55%)	Modest increase (5 - 15%)	Decrease (7 - 30%)	No change
Nicotinic acid (Niacin)	Modest decrease (5 - 25%) In combination with statins, may convert more dangerous LDL type to less dangerous.	Increase (15 - 35%) Drugs of choice for improving HDL levels	Decrease (20 - 50%) Drug of choice for lowering triglycerides	Decrease
Fibrates	Effect varies, but in general has little effect or modest decrease (5 - 20%)	Modest increase (6 - 20%)	Decrease (20 - 50%)	No change
Bile acid-binding resins	Decrease (15 - 30%)	Very modest increase (3 - 5%)	No change	No change

Statins are the most effective drugs for the treatment of high cholesterol, and may even prove important drugs for many people at risk for heart disease who have normal cholesterol levels. Statins inhibit the liver enzyme HMG-CoA reductase, which is used in the manufacturing of cholesterol. These drugs effectively reduce the risk of major coronary events, including first and second heart attacks, in both adult women and men of any age with unhealthy cholesterol levels. Experts estimate a 25 - 30% reduction in mortality rates when patients take statins after a heart attack. (Some believe the decrease may even be greater.) These drugs may also help improve the outcome in patients with heart disease who have had angioplasty.

Important studies have reported lower rates of heart attack, stroke, and mortality rates from all causes in statin users who were at high risk for heart disease, even if they had normal or low cholesterol levels. Benefits were similar in these people regardless of gender, age, or the presence of specific heart risk factors, such as diabetes or peripheral artery disease.

Brands. Statins are currently categorized into four groups:

So-called natural statins, including lovastatin (Mevacor, generics), pravastatin (Pravachol), and simvastatin (Zocor, generics). These are the most studied statins and have proven effectiveness and good safety record.
Synthetic statins include fluvastatin (Lescol) and atorvastatin (Lipitor). Studies using atorvastatin suggest they may reduce LDL more effectively than natural statins. In 2007, Lipitor was approved for additional indications to reduce the risk of heart attacks, strokes, certain types of heart surgery, hospitalization for heart failure, and chest pain in patients with heart disease. Lipitor is also approved for children.
The newer statins include rosuvastatin (Crestor), which was approved in 2003. Trial results have suggested that rosuvastatin is more effective in improving lipid profiles than atorvastatin, simvastatin, or pravastatin. However, like all statin drugs, rosuvastatin can cause serious side effects (see the Adverse Effects section in this report). The risks may be higher for Asian patients; this population should be started on the lowest rosuvastatin dose (5 mg).
Fixed-dose combination statins, which combine two drugs in one pill, first appeared on the market in 2004. Ezetimibe/simvastatin (Vytorin) combines two cholesterol medications that work in different ways. Simvastatin blocks cholesterol production in the liver, while ezetimibe (a non-statin cholesterol medication) blocks cholesterol absorption in the digestive tract. A 2005 study found that Vytorin was more effective than atorvastatin in lowering LDL and increasing HDL levels. Amlodipine/atorvastatin (Caduet) is a dual-therapy medication that combines the antihypertensive calcium channel blocker amlodipine with atorvastatin. It is used to treat simultaneously high blood pressure and high cholesterol.

Statins are generally administered once a day, typically in the evening because most cholesterol synthesis occurs between midnight and 3 a.m. (Atorvastatin and rosuvastatin, however, can be taken in the morning.) Statins are often prescribed along with other cholesterol-lowering drugs such as bile acid-binding resins, nicotinic acid (niacin), and fibrates.

Beneficial Effects on the Heart and Circulation.

Statins are particularly effective for lowering LDL levels. They also reduce triglycerides, apparently in direct proportion to their LDL-lowering effects. Statins also raise HDL levels, but to a lesser extent than other anti-cholesterol drugs. (The newer statins appear to produce more significant increases in HDL.) Evidence now strongly suggests that statins may offer other health benefits beyond lowering cholesterol:

Statins may improve the function of the endothelium (the lining of blood vessels), thereby improving blood flow. (This benefit apparently does not extend to people with diabetes.)
Statins appear to reduce inflammation in the arteries, which is now believed to be a major factor in blood vessel injury.
Some evidence suggests that statins may help prevent blood clotting, a major factor in heart attacks.

Beneficial Effects Outside the Heart. Studies also suggest that the benefits of statins go beyond the heart. At this time, nearly all studies on the following conditions have used natural statins:

Stroke. Statins may reduce the risk for ischemic stroke in high-risk patients with a wide range of cholesterol and lipid levels. (Ischemic strokes occur from blockage in the blood vessels that lead to the brain.) In 2003, statin therapy was shown to reduce both fatal and non-fatal stroke in patients with hypertension and at least three additional cardiovascular risk factors. A 2004 study of stroke patients found that those who were receiving statin therapy at the time of their stroke had more favorable long-term outcomes than patients who were not on statin therapy, suggesting that statin therapy may provide additional benefits to patients who develop stroke.
Diabetes. Statins may have a number of effects that are helpful for patients with diabetes, and may even prevent diabetes in some people with high cholesterol. Statins, however, do not appear to have any effect on blood vessel inflexibility in diabetes, which is an important risk factor for heart disease in these patients. A major 2003 study found that statin therapy helped prevent cardiovascular events including coronary death, heart attack, stroke, and the need for revascularization therapy in patients with diabetes, even in those who did not have high cholesterol levels or established coronary disease.
High Blood Pressure. In an important 2002 study, patients with high blood pressure but normal hMG-CoA reductase or slightly high cholesterol levels had fewer heart attacks and strokes when they took the statin atorvastatin. The study was stopped so all subjects could take statins. An earlier study showed similar benefits with the statin simvastatin.
Alzheimer's Disease. A number of studies have reported a significantly lower risk for Alzheimer's disease in people who take specific statins. Some evidence suggests they may even improve mental function in people without unhealthy cholesterol levels. Statins showing the greatest promise include lovastatin (Mevacor), pravastatin (Pravachol), and atorvastatin (Lipitor.) These statins appear to reduce levels of beta-amyloid. Other statins have not been associated with a lower risk for Alzheimer's. In fact, some researchers are concerned that certain statins that cross the blood-brain barrier may actually worsen Alzheimer's in people who already have it.
Kidney Disease. Statins may prove to protect against heart disease development in patients with mild kidney disorders. According to a 2004 study, statins may also help slow the progression of existing kidney disease.
Eye Disease. Studies are investigating whether statins can help prevent macular degeneration, an age-related eye disease that can lead to blindness. Research is still preliminary, and results have been mixed.

Macular degeneration is a disease of the retina that affects the macula in the back of the eye. The macula is important for clear central vision, allowing an individual to see fine details. There are two types of macular degeneration, dry and wet. Dry macular degeneration is more common and is characterized by the thinning of the retina and drusen, small white deposits that form within the retina. The dry form of macular degeneration is usually mild. Wet macular degeneration can happen more quickly and be more serious. It occurs when vessels under the retinal layer hemorrhage and cause the retinal cells to die, creating blind spots or distorted vision in the central vision. The disease becomes increasingly common among people in each succeeding decade over 50.

Adverse Effects. The statins tend to be better tolerated than other cholesterol-lowering drugs. In many studies the side effects reported were nearly the same as those taking placebo. Side effects may include gastrointestinal discomfort, headaches, skin rashes, muscle aches, sexual dysfunction, drowsiness, dizziness, nausea, constipation, and peripheral neuropathy (numbness or tingling in the hands and feet).

The primary safety concern with statins has involved an uncommon condition called myopathy, which can cause muscle damage and in some cases, muscle and joint pain. A specific myopathy, called rhabdomyolysis, can lead to kidney failure. Reports of rhabdomyolysis prompted the recall of cerivastatin (Baycol) in 2001. The risk for myopathy/rhabdomyolysis is highest at higher doses and in older people (over 65 years), those with hyperthyroidism, and those with renal insufficiency (kidney disease). Both statins and fibrates carry a risk for myopathy. The combination of the two drugs increases this side effect. Some people who use a statin-fibrate combination withdraw from the regimen because of muscle discomfort.

In 2005, the FDA issued a public health advisory for rosuvastatin (Crestor), noting that this drug, like other statins, increased the risk for myopathy and rhabdomyolysis. The risks were greatest at the highest dose level (40 mg). The FDA advises that patients should not start therapy at this dose. In addition, the FDA reported the results of a post-marketing study that found that people of Asian heritage had twice the blood levels of the drug as Caucasians who had taken the same dose. Because of this difference in drug metabolism, the FDA advises that Asian Americans should start treatment at the lowest rosuvastatin dose (5 mg). In general, all statin therapy should start at a lower dose and be raised incrementally until healthy cholesterol levels are maintained. Patients should immediately tell their doctor about any unusual muscle discomfort or weakness, fever, nausea or vomiting, or darkening of urine color.

Statins can also affect the liver, particularly at higher doses, so patients should have periodic liver function tests. Statins should not be taken by anyone with liver problems or by women during pregnancy or breast-feeding. Similarly, high statin doses increase the risk for kidney failure, particularly for patients with other existing risk factors (diabetes, hypertension, atherosclerosis, history of heart failure).

Interactions with Drugs and Food. Statins may have some adverse interactions with other drugs, including other cholesterol-lowering medications. Among the drugs that increase the risk for adverse effects are cyclosporine, macrolide antibiotics, and certain antifungals. Patients should tell their doctors about any other medications they are taking. Grapefruit juice and Seville oranges may increase statin potency.

Brands. Nicotinic acid is the active compound found in niacin, or vitamin B3. It is the first choice for patients with low HDL levels. Brands include Niacor, Nicolar, and Slo-Niacin. An extended-release form (Niaspan), administered at bedtime, may have fewer side effects, including headaches and flushing, than rapidly-acting niacin drugs. Although niacin is available over the counter, the active form used for cholesterol is given in much higher doses and is available only by prescription. It is important to take this medication under a doctor's direction in order to ensure its safety and effectiveness.

Benefits. When used in high doses, it has the following benefits:

Raises HDL levels higher than other anti-cholesterol drugs
Reducing triglyceride levels very effectively
Lowers LDL-cholesterol and lipoprotein(a)
Costs less than other anti-cholesterol drugs

Combinations with other drugs, particularly statins, may add significant benefits.

Side Effects. Many patients do not like the side effects of the rapidly-absorbed form of nicotinic acid. About a quarter of patients who use rapid-acting forms of nicotinic acid stop taking them. The most common side effects are flushing of the face and neck, itching, headache, blurred vision, and dizziness. They usually occur between 5 minutes to hours after taking the drug and can last for minutes to, uncommonly, hours. The body does eventually become tolerant to these effects, and they generally subside.

The following may reduce flushing and itching:

Starting with low doses taken at mealtime and gradually working up to the prescribed dose.
Taking low-dose aspirin about 30 minutes before taking nicotinic acid. This may help prevent flushing.
Avoiding hot drinks.
Choosing an extended release form. (Even with this form, it is wise to gradually increase the bedtime dose over time and take a low-dose aspirin a half-hour beforehand.)

Stomach problems are common. Other side effects include dry skin and mucous membranes and darkening of the skin.

About 30% of patients who take niacin experience elevated levels in blood glucose, which can be a problem for people with diabetes. Niacin's effects on HDL and triglycerides, however, are especially suited for the lipid imbalances that are common in diabetes. And, some studies report that people with diabetes who use niacin have little trouble with blood sugar control.

Potentially Serious Complications. About 3 - 5% of people taking nicotinic acid develop liver problems, which disappear after the medication is discontinued. The extended form (Niaspan) appears to be safe for the liver, but people with chronic liver disease should not use any form of nicotinic acid. People with gout should also avoid nicotinic acid because it elevates uric acid.

Bile-acid binding resins work, as their name suggests, by binding to bile in the digestive tract. This reduces cholesterol in the following way:

Bile is made in the liver and is used as one of the body's primary manufacturing components.

Click the icon to see an image of the gallbladder.

Once the resins bind to bile in the digestive tract, the bile is excreted in feces.
As the resins eliminate bile from the body, the liver takes more cholesterol from the bloodstream in order to produce more bile.
As cholesterol is taken out of the bloodstream, LDL levels drop.

When used in combination with dietary control, LDL levels are reduced by 15 - 20%. Combinations with nicotinic acid are even more effective, with reductions of 40 - 60% observed.

Brands. The bile-acid binding resins and similar drugs include cholestyramine (Questran, Questran Light). They are commonly used in a powder that is dissolved in liquid. Colesevelam (Welchol) is available in tablet form.

Side Effects. None of these drugs poses major risks. Most, however, cause constipation, heartburn, gas, and other gastrointestinal problems, side effects that many people cannot tolerate. One study found that only half the standard dose of colestipol was needed when psyllium, (a soluble fiber supplement found in Metamucil, Fiberall, and Perdiem), was added to the drink. In addition, bloating and constipation were reduced. Colesevelam, a newer resin, appears to have significantly fewer of these side effects.

Bile-acting drugs may contribute to calcium loss and therefore increase the risk for osteoporosis. Over time, deficiencies of vitamins A, D, E, and K may occur, and vitamin supplements may be necessary.

Rarely, toxic effects on the liver have been reported. Patients with liver disorders should be monitored.

Drug Interactions. Bile-acid binding resins may also interfere with other medications, including digoxin (Lanoxin), warfarin, beta-blocker drugs, and a number of medications used to treat low blood sugar. In order to prevent drug interactions, other drugs should be taken 1 hour before or 4 - 6 hours after taking the bile acid-binding resins.

Brands. Fibrates (sometimes called fibric acid derivatives) break down the particles that make triglycerides. Gemfibrozil is the standard fibrate. It is usually taken twice a day, 30 minutes before breakfast and before the evening meal. Newer fibrates, including fenofibrate (Lofibra, Tricor, Triglide), may be more effective in lowering cholesterol than gemfibrozil.

Benefits. Most fibrates have been shown to lower the risk of heart attack. In a 2001 study, men with both low HDL and LDL levels had a slightly lower risk of stroke after taking gemfibrozil. Fibric acid derivatives, or fibrates, have the following effects on cholesterol, lipids, and other factors:

They are good choices for many patients who need to lower triglyceride levels and increase HDL but who cannot take drugs ordinarily used for these purposes, such as nicotinic acid. In one study gemfibrozil, the standard fibrate, reduced the risk for adverse heart events by 22%.
Fibrates can produce modest reductions in LDL levels, although not as effectively as statins or other drugs. LDL may actually increase in patients with very high triglycerides who take these drugs. (The newer fibrates are much more effective in lowering LDL than gemfibrozil.)
A study on bezafibrate suggested it might have anti-inflammatory effects in patients with high triglyceride levels. Inflammation in the blood vessels is now recognized as a major contributor to the process leading to heart disease. However, according to a 2004 study, patients with diabetes or impaired fasting glucose levels were less likely to benefit from bezafibrate.
A study on fenofibrate further suggested that it reduced certain clotting factors (another risk factor for heart disease) and also uric acid (a risk factor for gout). Another study, published in 2004, demonstrated that like bezafibrate, fenofibrate has significant anti-inflammatory properties in patients with high triglyceride levels.

Concerns. Fibrates do not appear to reduce mortality rates. In one study, people who took gemfibrozil had higher rates of death from other causes, including cancer. Some evidence suggests that fibrates may affect receptors involved in cancer development. However, a number of studies have found no higher incidence of cancer.

Side Effects. Side effects may include gastrointestinal discomfort, aching muscles, sensitivity to sunlight, and skin rashes. Fibrates have been known to cause gallstones, so people with gallbladder problems should not use these drugs.

Click the icon to see an image of gallstones in the gallbladder.

The drugs may cause abnormal heart rhythms and can affect the liver and kidney.

Drug Interactions. Fibrates interact with a number of drugs and substances including warfarin, some oral drugs used for diabetes, certain antibiotics, and grapefruit juice.

Ezetimibe (Zetia) blocks absorption of cholesterol that comes from food. Ezetimibe is usually prescribed alone or in combination with a statin. In 2004, the FDA approved Vytorin, which combines ezetimbe and the statin simvastatin into a single pill.

In 2006, the FDA approved the use of ezetimbe in combination with fenofibrate (Tricor) for reduction of total cholesterol and LDL in patients with mixed hyperglycemia (high LDL levels, high triglycerides, low HDL levels) whose cholesterol has not been adequately controlled through diet alone. Fenofibrate is a cholesterol drug that is used along with diet to reduce LDL and triglycerides.

CETP Inhibitors. Cholesteryl ester transfer protein (CETP) inhibitors, such as the experimental drug torcetrapib, are a new drug class that is being investigated for its effect on raising HDL ("good" cholesterol) levels while lowering LDL ("bad") cholesterol levels. Torcetrapib was the most widely studied of these drugs. However, in December 2006, the drug’s manufacturer abruptly stopped late-stage clinical trials after discovering that torcetrapib significantly increased blood pressure and risk of death.

Several studies published in 2007 in the New England Journal of Medicine revealed that while torcetrapib does greatly boost HDL levels (by 61% in one study) and lower LDL, it has no effect on arterial plaque. Scientists are trying to understand why this drug did not work. One theory is that torcetrapib may have increased the quantity of HDL, but not the quality. It is still not clear whether the failure of trocetrapib is specific to this drug or the entire CETP drug class. Given the current findings, it is also unclear whether research will continue on other CETP drugs.

Selective Estrogen-Receptor Modulators(SERMs). Selective estrogen-receptor modulators (SERMs) have been designed to produce the benefits of estrogen without its risks. They are thought to act like estrogen in some tissues but behave like estrogen blockers (antiestrogens) in others. They include tamoxifen (Nolvadex), raloxifene (Evista), and droloxifene. Any beneficial effects of the SERMs on cholesterol and the heart are still unclear. SERMs pose a risk for deep vein blood clots, which may have implications for people with heart problems. Longer studies are needed on possible risks and benefits.

Recombinant ApoA-I Milano. ApoA-I Milano is a type of HDL protein that is found in people with very low levels of HDL. A 2003 study showed that treating patients with a synthetic form of HDL, derived from ApoA-I Milano, caused a significant regression of atherosclerosis. Ongoing trials will evaluate whether this drug can prevent cardiovascular events such as heart attack or death.

Plasmapheresis and Familial Hypercholesterolemia. Plasmapheresis is a blood-filtering procedure that is used to dramatically reduce triglycerides and may also be used to remove LDL. The procedure may be beneficial for patients with severe hereditary forms of high cholesterol who do not respond to other therapies. Studies suggest, for example, that plasmapheresis is particularly useful for patients with familial hypercholesterolemia. The process takes about 3 hours. If not performed regularly, its benefits last only about 2 weeks. People using this procedure are still advised to maintain a healthy diet and continue to take any prescribed medications to control cholesterol.

Resources

www.nhlbi.nih.gov/about/ncep -- National Cholesterol Education Program
www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.acc.org -- American College of Cardiology
www.americanheart.org -- American Heart Association
www.eatright.org -- American Dietetic Association

References

Berthold HK, Unverdorben S, Degenhardt R, Bulitta M, Gouni-Berthold I. Effect of policosanol on lipid levels among patients with hypercholesterolemiaor combined hyperlipidemia: a randomized controlled trial. JAMA. 2006 May 17;295(19):2262-9.

Covas MI, Nyyssonen K, Poulsen HE, Kaikkonen J, Zunft HJ, Kiesewetter H, et al. The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial. Ann Intern Med. 2006 Sep 5;145(5):333-41.

Crouse JR 3rd, Raichlen JS, Riley WA, Evans GW, Palmer MK, O'Leary DH, et al. Effect of rosuvastatin on progression of carotid intima-media thickness in low-risk individuals with subclinical atherosclerosis: The METEOR Trial. JAMA. 2007 Mar 25; [Epub ahead of print]

Deedwania P, Barter P, Carmena R, Fruchart JC, Grundy SM, Haffner S, et al. Reduction of low-density lipoprotein cholesterol in patients with coronary heart disease and metabolic syndrome: analysis of the Treating to New Targets study. Lancet. 2006 Sep 9;368(9539):919-28.

Estruch R, Martinez-Gonzalez MA, Corella D, Salas-Salvado J, Ruiz-Gutierrez V, Covas MI, et al. Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomized trial. Ann Intern Med. 2006 Jul 4;145(1):1-11.

Gardner CD, Kiazand A, Alhassan S, Kim S, Stafford RS, Balise RR, et al. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77.

Gardner CD, Lawson LD, Block E, Chatterjee LM, Kiazand A, Balise RR, et al. Effect of raw garlic vs commercial garlic supplements on plasma lipid concentrations in adults with moderate hypercholesterolemia: a randomized clinical trial. Arch Intern Med. 2007 Feb 26;167(4):346-53.

Jolliffe CJ, Janssen I. Distribution of lipoproteins by age and gender in adolescents. Circulation. 2006 Sep 5;114(10):1056-62. Epub 2006 Aug 28.

Kastelein JJ, van Leuven SI, Burgess L, Evans GW, Kuivenhoven JA, Barter PJ, et al. Effect of torcetrapib on carotid atherosclerosis in familial hypercholesterolemia. N Engl J Med. 2007 Mar 26; [Epub ahead of print]

McCrindle BW, Urbina EM, Dennison BA, Jacobson MS, Steinberger J, Rocchini AP, et al. Drug therapy of high-risk lipid abnormalities in children and adolescents. A scientific statement from the American Heart Association Atherosclerosis, Hypertension, and Obesity in Youth Committee, Council of Cardiovascular Disease in the Young, With the Council on Cardiovascular Nursing. Circulation. 2007 Mar 21; [Epub ahead of print]

McMillan-Price J, Petocz P, Atkinson F, O'Neill K, Samman S, Steinbeck K, et al. Comparison of 4 diets of varying glycemic load on weight loss and cardiovascular risk reduction in overweight and obese young adults: a randomized controlled trial. Arch Intern Med. 2006 Jul 24;166(14):1466-75.

Nissen SE, Tardif JC, Nicholls SJ, Revkin JH, Shear CL, Duggan WT, et al. Effect of torcetrapib on the progression of coronary atherosclerosis. N Engl J Med. 2007 Mar 26; [Epub ahead of print]

Review Date:
7/23/2007
Reviewed By:
Alan Greene, MD, FAAP, Chief Medical Officer, A.D.A.M., Inc.; and Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Exercise

FitSugar — Wed, 08 Oct 2008 17:35:02 -0700

In This Report

Highlights
Introduction
Recommended Exercise Method...
Exercise's Effects on the H...
Exercise's Effects on Diabe...
Exercise's Effects on Bones...
Exercise's Effects on the L...
Exercise's Effects on Weigh...
Exercise's Effects on Other...
Complications
Motivation
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Chronic Conditions and Exercise:

A new study found that aerobic and resistance training significantly reduced fatigue in men undergoing radiation treatments for prostate cancer. Fatigue is a common side effect of such treatments.
Doctors at the Mayo Clinic found that exercise improves the physical and emotional well-being of patients with Alzheimer's disease. The patients exercised for as little as 60 minutes each week. Doctors noted improvements in areas ranging from depression to wandering.

Exercise and Smoking:

A 2007 review of existing studies found that moderate exercise, for as little as 5 minutes, can help combat the nicotine withdrawal symptoms people experience when they try to stop smoking.

Exercise and Aging:

A 2006 report found that older and elderly adults who exercised twice a week for 4 months significantly increased their body strength, flexibility, balance, and agility. The average age of the study participants was 83.5.

Before and After Exercising:

You should do warm-up exercises for 5 - 10 minutes at the beginning of an exercise session. Low-level aerobic exercise is the best warm-up.
To cool down, you should walk slowly until your heart rate is 10 - 15 beats above your resting heart rate. Stopping too suddenly may sharply reduce blood pressure or cause muscle cramping.
You must be careful when stretching during your warm-up to avoid injuring cold muscles.

Definitions:

Aerobic exercise: Aerobic exercise forces the heart and lungs to work harder for longer periods. It builds endurance, improves blood flow throughout the body, and increases the levels of "good" cholesterol.
Resistance Training: Resistance training works muscles against a force (usually weights). It burns fat and builds muscle.

Introduction

Everyone's goal of living a long and healthy life should include a healthy diet, regular exercise, and maintaining normal weight. The combination of inactivity and eating the wrong foods is the second most common preventable cause of death in the United States (smoking is the first).

Most research on the benefits of exercise focuses on heart protection. Studies clearly show that exercise helps the heart. In addition, new studies are reporting that even people at higher risk for heart disease may lower their risk of dying from it if they exercise.

Evidence suggests that our genes evolved to favor exercise. In other words, during prehistoric times, if a person couldn't move quickly and wasn't strong, he or she died. Those who were fit survived to reproduce and pass on these "fitter" genes. Some researchers believe that with our current inactive lifestyle, these genes produce a number of bad effects, which can lead to many chronic illnesses.

The benefits of exercise include:

Improved oxygen delivery throughout the body
Improved metabolic processes - the way the body breaks down and builds necessary substances
Improved strength and endurance
Decreased body fat
Improved movement of joints and muscles
Improved sense of well-being

In addition, exercise can help change other dangerous lifestyle habits. A 2007 review of existing studies found that moderate exercise, for as little as 5 minutes at a time, can help combat the nicotine withdrawal symptoms people experience when they try to stop smoking.

No one is too young or too old to exercise. The United States Surgeon General recommends at least 30 minutes of moderate exercise, such as brisk walking, nearly every day. However, vigorous exercise carries risks that people should discuss with a doctor. You should always check with your doctor before starting a new exercise program, especially if you have any of the following risk factors:

History of smoking
Obesity
Family history of a long-term disease
A symptom you haven’t told your doctor about
Chest pain
Shortness of breath
Heart palpitations
Blood clots
Infections
Fever
Unexplained weight loss
Foot or ankle sores that won’t heal
Joint swelling
Pain or trouble walking after a fall
Eye injury or eye surgery
Hernia
Hip surgery

Fifty percent of all people who begin a vigorous training program drop out within a year. The key to reaching and maintaining physical fitness is to find activities that are exciting, challenging, and satisfying.

Recommended Exercise Methods

A few simple rules are helpful as you develop your own routine.

Don't eat for 2 hours before vigorous exercise.
Drink plenty of fluids before, during, and after a workout.
Adjust your activity level according to the weather, and reduce it when you are fatigued or ill.
When exercising, listen to the body's warning symptoms, and consult a doctor if exercise causes chest pain, irregular heartbeat, undue fatigue, nausea, unexpected breathlessness, or light-headedness.

Heart rate is the standard guide for determining aerobic exercise intensity. It can be determined by counting one's own pulse or with the use of a heart rate monitor. To feel your own pulse, press the first two fingers of one hand gently down on the inside of the wrist or under the jaw on the right or left side of the front of the neck. You should feel a faint pounding as blood passes through the artery. Each pounding is a beat.

Click the icon to see how to take a radial pulse

Click the icon to see how to take a carotid pulse.

There are different types of heart rates.

Resting heart rate. The average heart rate for a person at rest is 60 - 80 beats per minute. It is usually lower for people who are physically fit, and often rises as you get older. You can determine your resting heart rate by counting how many times your heart beats in one minute. The best time to do this is in the morning after a good night’s sleep before you get out of bed.

Maximum heart rate. To determine your own maximum heart rate per minute subtract your age from 220. For example, if you are 45, you would calculate your maximum heart rate as follows: 220 - 45= 175.

Target heart rate. Your target rate is 50 - 75% of your maximum heart rate. You should measure your pulse off and on while your exercise to make sure you stay within this range. After about 6 months of regular exercise, you may be able to increase your target heart rate to 85% (but only if you can comfortably do so).

Certain heart medications may lower your maximum and target heart rates. Always check with your doctor before starting an exercise program.

Note: Swimmers should use a heart rate target of 75% of the maximum and then subtract 12 beats per minute. The reason for this is that swimming will not raise the heart rate quite as much as other sports because of the so-called "diving reflex," which causes the heart to slow down automatically when the body is immersed in water.


Age	Low	High
	(50% max.)	(75% max.)
20	100	150
30	95	142
40	90	135
50	85	127
60	80	120
Source: American Heart Association

VO2 Max. Serious exercisers may use a VO2 max calculation, which measures the amount of oxygen consumed during intensive, all-out exercise. The most accurate testing method uses computers, but anyone can estimate V02 without instrumentation (with an accuracy of about 95%):

After running at top pace for 15 minutes, round off the distance run to the nearest 25 meters.
Divide that number by 15.
Subtract 133.
Multiply the total by 0.172, then add 33.3.

Olympic and professional athletes train for VO2 max levels above 80. But for the average person interested in fitness, a VO2 max equaling between 50 and 80 is considered an excellent score for overall fitness.

Click the icon to see an image on exercise and heart rate.

Warming up and cooling down are important parts of every exercise routine. They help the body make the transition from rest to activity and back again, and can help prevent soreness or injury, especially in older people.

Warm-up exercises should be practiced for 5 - 10 minutes at the beginning of an exercise session. Older people need a longer period to warm up their muscles. Low-level aerobic exercise such as brisk walking, swinging the arms, or jogging in place, is the best approach.
To cool down, you should walk slowly until the heart rate is 10 - 15 beats above your resting heart rate. Stopping too suddenly can sharply reduce blood pressure, and is dangerous for older people. It may also cause muscle cramping.
Stretching may be appropriate for the cooling down period, but it must be done carefully for warming up because it can injure cold muscles. (There is no clear evidence, however, that stretching reduces muscle injuries.)

Warming up before exercise and cooling down after is just as important as the exercise itself. By properly warming up the muscles and joints with low-level aerobic movement for 5 - 10 minutes, one may avoid injury and build endurance over time. Cooling down after exercise by walking slowly, then stretching muscles, may also prevent strains and blood pressure fluctuation.

For most people, exercise may be divided into three general categories:

Aerobic or endurance
Strength or resistance
Flexibility

A balanced program should include all three. Speed training is also a major category, but generally only competitive athletes practice it.

Benefits of Aerobic Exercise. Regular aerobic exercise provides the following benefits:

Builds endurance
Keeps the heart pumping at a steady and high rate for a long time
Boosts HDL ("good") cholesterol levels
Helps control blood pressure
Strengthens the bones in the spine
Helps maintain normal weight
Improves one's sense of well-being

Types of Aerobic Exercise. Aerobic exercise is usually categorized as high or low impact. Examples of each include the following:

Low- to moderate-impact exercises: Walking, swimming, stair climbing, step classes, rowing, and cross-country skiing. Nearly anyone in reasonable health can engage in some low- to moderate-impact exercise. Brisk walking burns as many calories as jogging for the same distance and poses less risk for injury to muscle and bone.
High-impact exercises: Running, dance exercise, tennis, racquetball, squash. High-impact exercises should be performed no more than every other day, and less often for those who are overweight, elderly, out of condition, or have an injury or other medical problem that would rule out high-impact.

Click the icon to see an image of aerobic exercise.

Aerobic Regimens. As little as one hour a week of aerobic exercises is helpful, but 3 - 4 hours per week are best. Some research indicates that simply walking briskly for 3 or more hours a week reduces the risk for coronary heart disease by 65%. In general, the following guidelines are useful for most individuals:

For most healthy young adults, the best approach is a mix of low- and higher-impact exercise. Two weekly workouts will maintain fitness, but three to five sessions a week are better.
People who are out of shape or elderly should start aerobic training gradually. For example, they may start with 5 - 10 minutes of low-impact aerobic activity every other day and build toward a goal of 30 minutes per day, three to seven times a week. (For heart protection, frequency of exercises may be more important than duration.)
Swimming is an ideal exercise for many elderly and certain people with physical limitations, including pregnant women, individuals with muscle, joint, or bone problems, and those who suffer from exercise-induced asthma.
People who seek to lose weight should aim for six to seven low-impact workouts a week.

One way of gauging the optimal intensity of exercise is to aim for a "talking pace," which is enough to work up a sweat and still be able to converse with a friend without gasping for breath. As fitness increases, the "talking pace" will become faster and faster.

Shoes. All that's really necessary for a workout is a good pair of shoes that are made well and fit well. They should be broken in, but not worn down. They should support the ankle and provide cushioning for impact sports such as running or aerobic dancing. Airing out the shoes and feet after exercising reduces chances for skin conditions such as athlete's foot.

Clothing. Comfort and safety are the key words for workout clothing. For outdoor nighttime exercise, a reflective vest and light-colored clothing must be worn. Bikers, roller bladers, and equestrians should always wear safety devices such as helmets, wrist guards, and knee and elbow pads. Goggles are mandatory for indoor racquet sports. For vigorous athletic activities, such as football, ankle braces may be more effective than tape in preventing ankle injuries.

Aerobic-Exercise Equipment. Home aerobic exercise machines can be adapted to any fitness level and used day or night. Before investing in any exercise machine, however, it is wise to first test it at a gym. In addition, initial supervised training when using these machines can reduce the risk of injury that might occur with self-instruction.

Very inexpensive exercise machines tend to be flimsy and hard to adjust, but many sturdy machines are available at moderate prices. The higher-end models may utilize computers to record calories burned, speed, and mileage. While their readouts may provide motivation and gauge the intensity of a workout, however, they are not always accurate.

The following are a few observations on specific equipment:

A good floor mat is important to provide cushioning for all home exercises.
A simple jump rope improves aerobic endurance for people who are able to perform high-impact exercise. Jumping rope should be done on a floor mat plus a surface that has some give to avoid joint injury.
For burning calories, the treadmill has been ranked best, followed by stair climbers, the rowing machine, cross-country ski machine, and stationary bicycle. (Elliptical trainers, however, may be even better than treadmills for increasing heart rate, calorie expenditure, and oxygen consumption.)
Stationary bikes condition leg muscles and are fairly economical and easy to use safely. The pedals should turn smoothly, the seat height should adjust easily, and the bike's computer should be able to adjust intensity.
Stair machines also condition leg muscles. They offer very intense, low-impact workouts and may be as effective as running with less chance of injury.
Rowing and cross-country ski machines exercise both the upper and lower body.


Aerobic dancing	Sufficient cushioning to absorb shock and pressure that are many times greater than ordinary walking. Arches that maintain side-to-side stability. Thick upper leather support. Toe-box. Orthotics may be required for people with ankles that over-turn inward or outward. Soles should allow for twisting and turning.
Cycling	Rigid support across the arch to prevent collapse during pedaling. Heel lift. Cross-training or combination hiking/cycling shoes may be sufficient for casual bikers. Toe clips or specially designed shoe cleats for serious cyclers. In some cases, orthotics may be needed to control arch and heel and balance forefoot.
Running	Sufficient cushioning to absorb shock and pressure. Fully bendable at the ball of the foot. Sufficient traction on sole to prevent slipping. Consider insoles or orthotics with arch support for problem feet.
Tennis	Allow side-to-side sliding. Low-traction soles. Snug fitting heels with cushioning. Padded toe box with adequate depth. Soft-support arch.
Walking	Lightweight. Breathable upper material (leather or mesh). Wide enough to accommodate ball of the foot. Firm padded heel counter that does not bite into heel or touch ankle bone. Low heel close to ground for stability. Good arch support. Front provides support and flexibility.

Benefits of Strength Exercise. While aerobic exercise increases endurance and helps the heart, it does not build upper body strength or tone muscles. Strength-training exercises provide the following benefits:

Build muscle strength while burning fat
Help maintain bone density
Improve digestion

It is also associated with a lower risk for heart disease, possibly because it lowers LDL (the so-called "bad") cholesterol levels.

Click the icon to see an image of cholesterol.

Strength exercise is beneficial for everyone, even people in their 90s. It is the only form of exercise that can slow and even reverse the decline in muscle mass, bone density, and strength that occurs with aging. Please note: People at risk for cardiovascular disease should not perform strength exercises without checking with a doctor.

Types of Muscle Contractions. There are three types of muscle contractions involved in strength training:

Isometric contractions do not change the length of the muscle. An example is pushing against a wall.
Concentric contractions shorten muscles. An example is the "up" phase of a bicep curl.
Eccentric contractions lengthen muscles. An example is the "down" phase as weights are lowered.

Click the icon to see an image of isometric exercise.

Strength-Training Regimens. Strength training involves intense and short-duration activities. For beginners, adding 10 - 20 minutes of modest strength training two to three times a week may be appropriate. The following are some guidelines for starting a strength regimen:

The sequence of a strength training session should begin with training large muscles and multiple joints at higher intensity and end with small muscle and single joint exercises at lower intensities.
Both shortening and lengthening muscle actions should be performed. Emphasizing the movements that lengthen muscles is of increasing interest. This approach involves slowing and increasing the duration of these "down" movements. It appears to significantly increase blood flow, and some evidence suggests it may achieve stronger muscles more quickly. It may also improve heart function compared to standard movements. Exercises that lengthen muscles may be particularly beneficial for older people and some people with chronic health problems. This type of training increases the risk for muscle soreness and injury, however, and this approach is still controversial.
Strength training involves moving specific muscles in the same pattern against a resisting force (such as a weight) for a preset number of times. This is called a repetition. Students should first choose a weight that is about half of what would require a maximum effort in one repetition. In other words, if it would take maximum effort to do a single repetition with a 10-pound dumbbell, the person would start with a five-pound dumbbell. In the beginning, most people can start with one set of 8 - 15 repetitions per muscle group with low weights. As individuals are able to perform one or two repetitions over their routine, weights can be increased by 2 - 10%.
Breathe slowly and rhythmically. Exhale as the movement begins. Inhale when returning to the starting point.
The first half of each repetition typically lasts 2 - 3 seconds. The return to the original position lasts 4 seconds.
An alternative technique called "super slow" training stretches out one repetition to a 14-second count. This method places far more stress on the muscle group, so fewer repetitions are needed. A full week of recovery is required before repeating this workout. The goal is to initiate changes in the muscles so that the body continues to burn calories after the exercise. Some people report dramatic results from this approach, but scientific proof of these claims is not available. It is a very tedious workout, and people have a hard time sticking with it. People with high blood pressure should not use this approach.
Joints should be moved rhythmically through their full range of motion during a repetition. Do not lock up the joint while exercising it.
For maximum benefit, one should allow 48 hours between workouts for full muscle recovery.

Click the icon to see the proper way to breathe during exercise.

Strength-Training Equipment. Unlike aerobic exercise, strength training almost always requires some equipment. Strength-training equipment does not, however, have to cost anything.

Any heavy object that can be held in the hand, such as a plastic bottle filled with sand or water, can serve as a weight.
Dumbbells (1 - 10 pounds) and resistance bands are inexpensive, portable, and effective.
Wearable weights help strengthen and tone the upper body.
Ankle weights strengthen and tone muscles in the lower body. Wearable ankle weights should not be worn during high-impact aerobics or jumping.
Hand grips strengthen arms and are good for relieving tension.
A pull-up bar can be mounted in a doorway for chin-ups and pull-ups.

More elaborate and expensive home equipment for working body muscles is also available, costing from $100 to over $1,000. No one should purchase or use strength-training equipment without instruction from a professional.

Benefits of Flexibility Training. Flexibility training uses stretching exercises. Many stretching exercises are particularly beneficial for the back. In general, flexibility training provides the following benefits:

Prevents cramps, stiffness, and injuries
Improves joint and muscle movement (improved range of motion)

Certain flexibility practices, such as yoga and tai chi, also involve meditation and breathing techniques that reduce stress. Such practices appear to have many health and mental benefits. They may be very suitable and highly beneficial for older people, and for patients with certain chronic diseases.

Click the icon to see an image of flexibility exercise.

Flexibility Training Regiments. Doctors recommend performing stretching exercises for 10 to 12 minutes at least three times a week. The following are some general guidelines:

When stretching, exhale and extend the muscles to the point of tension, not pain, and hold for 20 - 60 seconds. (Beginners may need to start with a 5- to 10-second stretch.)
Breathe evenly and constantly while holding the stretch.
Inhale when returning to a relaxed position. Holding your breath defeats the purpose; it causes muscle contraction and raises blood pressure.
When doing stretches that involve the back, relax the spine to keep the lower back flush with the mat, and to work only the muscles required for changing position (often these are only the abdominal muscles).

Studies continue to show that it is never too late to start exercising. A report published in the February 2006 Journal of Aging and Health found that elderly adults who exercised twice a week for four months significantly increased their body strength, flexibility, balance, and agility. The exercise program included walking and lifting weights. The average age of the study participants was 83.5. The study adds further evidence that even small improvements in physical fitness and activity can prolong life and independent living.

Still, about half of Americans over 60 describe themselves as sedentary (inactive). According to a 2004 report by the Centers for Disease Control and Prevention, approximately 12% of people aged 65 - 75 years and 10% of people aged 75 years or older meet current recommendations for strength training.

The following tips for exercising may be helpful:

Any older person should have a complete physical and medical examination, as well as professional instruction, before starting an exercise program.
Start low and go slow. For sedentary, older people, one or more of the following programs may be helpful and safe: Low-impact aerobics, gait (step) training, balance exercises, tai chi, self-paced walking, and lower legs resistance training, using elastic tubing or ankle weights. Even in the nursing home, programs aimed at improving strength, balance, gait, and flexibility have significant benefits.
Strength training assumes even more importance as one ages, because after age 30 everyone undergoes a slow process of muscular erosion. The effect can be reduced or even reversed by adding resistance training to an exercise program. As little as one day a week of resistance training improves overall strength and agility. Strength training also improves heart and blood vessel health.
Power training, which aims for the fastest rate at which a muscle or muscle group can perform work, may be particularly helpful for older women in strengthening muscles and preventing falls.
Flexibility exercises promote healthy muscle growth and help reduce the stiffness and loss of balance that accompanies aging.
Chair exercises may be performed by people who are unable to walk.
Older women are at risk for incontinence accidents during exercise. This can be reduced or prevented by performing Kegel exercises, limiting fluids (without risking dehydration), going to the bathroom frequently, and using leakage prevention pads or insertable devices.

Exercise's Effects on the Heart

Inactivity is one of the major risk factors for heart disease. However, exercise helps improve heart health, and can even reverse some heart disease risk factors.

Like all muscles, the heart becomes stronger as a result of exercise, so it can pump more blood through the body with every beat and continue working at maximum level, if need be, with less strain. The resting heart rate of those who exercise is also slower, because less effort is needed to pump blood.

A person who exercises often and vigorously has the lowest risk for heart disease, but any amount of exercise is beneficial. Studies consistently find that light-to-moderate exercise is even beneficial in people with existing heart disease. Note, however, that anyone with heart disease should seek medical advice before beginning a workout program.

The heart is a large muscular organ that pumps blood throughout the body. Valves inside the heart open and close. This controls how much blood enters or leaves the heart.

Exercise has a number of effects that benefit the heart and circulation (blood flow throughout the body). These benefits include improving cholesterol and fat levels, reducing inflammation in the arteries, assisting weight loss programs, and helping to keep blood vessels flexible and open. Studies continue to show that physical activity and avoiding high-fat foods are the two most successful means of reaching and maintaining heart-healthy levels of fitness and weight.

The American Heart Association recommends that individuals perform moderately-intense exercise for at least 30 minutes on most days of the week. This recommendation supports similar exercise guidelines issued by the Centers for Disease Control and Prevention, and the American College of Sports Medicine.

Coronary Artery Disease. People who maintain an active lifestyle have a 45% lower risk of developing heart disease than do sedentary people. Experts have been attempting to define how much exercise is needed to produce heart benefits. In 2002, a well-conducted study on overweight adults confirmed previous research that reported beneficial changes in cholesterol and lipid levels, including lower LDL levels (bad cholesterol), even when people performed low amounts of moderate- or high-intensity exercise such as walking or jogging 12 miles a week. However, more intense exercise is required to significantly change cholesterol levels, notably increasing HDL (good cholesterol). An example of this kind of program would be jogging about 20 miles a week. Such benefits in the study occurred even with very modest weight loss, suggesting that overweight people who have trouble losing pounds can still achieve considerable heart benefits by exercising.

Resistance (weight) training has also been associated with heart protection. It may offer a complementary benefit to aerobics by reducing LDL levels. Exercises that train and strengthen the chest muscles may prove to be very important for patients with angina.

Effects of Exercise on Blood Pressure. Regular exercise helps keep arteries elastic (flexible), even in older people. This, in turn, ensures good blood flow and normal blood pressure. Sedentary people have a 35% greater risk of developing high blood pressure than athletes do.

Click the icon to see the risks associated with untreated hypertension.

It should be noted that high-intensity exercise may not lower blood pressure as effectively as moderate-intensity exercise. In one study, moderate exercise (jogging 2 miles a day) controlled high blood pressure so well that more than half the patients who had been taking drugs for the condition were able to discontinue their medication. However, a small study published in 2005 suggests that moderate exercise does not have a significant impact on systolic blood pressure (the top number) in older adults. While those who exercised did have notable drops in both the top and lower (diastolic) blood pressure levels, the only statistically significant change was the decrease in the lower number.

Experts recommend at least 30 minutes of exercise on most -- if not all -- days. Studies show that yoga and tai chi, an ancient Chinese exercise involving slow, relaxing movements, may lower blood pressure almost as well as moderate-intensity aerobic exercises.

Click the icon to see an image of someone practicing yoga.

Anyone with existing high blood pressure should discuss an exercise program with their doctor. Before starting to exercise, people with moderate-to-severe high blood pressure should lower their pressure, and be able to control it with medications. Everyone, and especially people with high blood pressure, should breathe as normally as possible through each exercise. Holding the breath increases blood pressure.

Effects of Exercise on Heart Failure. Traditionally, heart failure patients have been discouraged from exercising. Now, exercise performed under medical supervision is proving to be helpful for select patients with stable heart failure.

Studies continue to report benefits from exercise training. In one study, heart failure patients as old as 91 years old increased their oxygen use significantly, after 6 months of supervised treadmill and stationary bicycle exercises.
Progressive resistance training may be particularly useful for heart failure patients, since it strengthens muscles, which commonly weaken in this disorder. Even simply performing daily handgrip exercises can improve blood flow through the arteries.

Experts warn, however, that exercise is not appropriate for all heart failure patients.

All stroke survivors should have a pre-exercise evaluation done by their doctor before starting an exercise program.

The effects of exercise on stroke are less established than those on heart disease, but most studies show benefits. The following are some examples:

According to one major analysis, men cut their risk for stroke in half if their exercise program was roughly equivalent to about an hour of brisk daily walking 5 days a week. In the same study, exercise that involved recreation was more protective against stroke than exercise routines consisting simply of walking or climbing.
A 2000 study of women also found substantial protection from stroke in brisk walking or striding (rather than casual walking).

Anyone with heart disease or risk factors for developing heart disease or stroke should seek medical advice before beginning a workout program. Patients with heart disease can nearly always exercise safely as long as they work out under medical supervision. Still, it is often difficult for a doctor to predict health problems that might arise as the result of an exercise program. At-risk individuals should be very aware of any symptoms warning of harmful complications while they exercise.

Some experts believe that anyone over 40 years old, whether or not they are at risk for heart disease, should have a complete physical examination before starting or intensifying an exercise program. Some doctors use a questionnaire for people over 40 to help determine whether they require such an examination. The questions they use are as follows:

Has any doctor previously recommended medically supervised activity because of a heart condition?
Is chest pain brought on by physical activity?
Has chest pain occurred during the previous month?
Does the person faint or fall over from dizziness?
Is bone or joint pain intensified by exercise?
Has medication been prescribed for hypertension (high blood pressure) or heart problems?
Is the person aware of or has a doctor suggested any physical reason for not exercising without medical supervision?

Those who answer "yes" to any of the above questions should have a complete medical examination before developing an exercise program.

Stress Test. A stress test helps determine the risk for a heart problem resulting from exercise. Anyone with a heart condition or history of heart disease should have a stress test before starting an exercise program. Experts currently also recommend this test before a vigorous exercise program for older persons who are sedentary, even in the absence of known or suspected heart disease. The test is expensive, however, and some experts believe that it may not be necessary for many older people with no evident health problems or risk factors.

A small percentage of heart attacks occur after heavy physical work.

High-Risk Individuals. In general, the following people should avoid intense exercise or start it only with careful monitoring:

People who have certain medical conditions: These conditions include uncontrolled diabetes, uncontrolled seizures, uncontrolled high blood pressure, a heart attack within the previous 6 months, heart failure, unstable angina, significant aortic valve disease, or aortic aneurysm.
People with moderate-to-severe hypertension: Experts generally recommend that moderate or severe high blood pressure (systolic blood pressure over 160 mm Hg or diastolic (bottom number) pressure over 100 mm Hg) should be brought to lower levels before a person starts a vigorous exercise program.
Sedentary people should be cautious. One major study found that sedentary people who throw themselves into a grueling workout significantly increase their risk of heart attack.
Episodes of exercise-related sudden death in young people are rare but of great concern. Some are preceded by fainting, which is due to a sudden and severe drop in blood pressure. It should be noted that fainting is relatively common in athletes, and is dangerous only in people with existing heart conditions. Young people with genetic or congenital (present at birth) heart disorders should avoid intensive competitive sports.
Anabolic steroids or products containing ephedra have been associated with cases of stroke, heart attack, and even death.

The risk for heart attack from exercise should be kept in perspective, however. Some form of exercise, carefully personalized, has benefits for most of the individuals mentioned above. In many cases, particularly when the only risk factors are a sedentary lifestyle and older age, exercise can often be increased over time until it is intense.

Hazardous Activities for High-Risk Individuals. The following activities may pose particular dangers for high-risk individuals:

Intense workouts (snow shoveling, slow jogging, speed walking, tennis, heavy lifting, heavy gardening) may be particularly hazardous for people with risk factors for heart disease, especially older people. They tend to stress the heart, raise blood pressure for a brief period, and may cause spasms in the arteries leading to the heart. (See image: Coronary Artery Spasm)
Some studies suggest that competitive sports, which couple intense activity with aggressive emotions, are more likely to trigger a heart attack than other forms of exercise.

Listening for Warning Signs. It should be noted that according to one study, at least 40% of young men who die suddenly during a workout have previously experienced, and ignored, warning signs of heart disease. In addition to avoiding risky activities, the best preventive tactic is simply to listen to the body and seek medical help at the first sign of symptoms during or following exercise. These symptoms include the following:

Irregular heartbeat
Shortness of breath
Chest pain

Click the icon to see an image of a coronary artery spasm.

Click the icon to see an image of stable angina.

Exercise's Effects on Diabetes

Moderate aerobic exercise can lower your risk for type 2 diabetes. An important study found that adults who worked out 2 and 1/2 hours a week cut their risk by 58%.

Exercise has positive benefits for those who have diabetes. It can lower blood sugar, improve insulin sensitivity, and strengthen the heart. Strength training, which increases muscle and reduces fat, may be particularly helpful for people with diabetes, but more evidence is needed to confirm this theory. One study reported that yoga helped patients with type 2 diabetes reduce their need for oral medications.

In 2005, researchers found that people with type 2 diabetes who walked a minimum of 3 miles every day were in better health, and had lower medical expenses, after 2 years of such exercise. Those who remained sedentary for that time period experienced a decline in their overall health and higher health care-related expenses. Study participants who worked out for an average of 38 minutes per day lowered their blood pressure, cholesterol ,and A1C levels (glucose concentration over time). These participants also had lower heart disease risk, even if they didn't lose weight. The increase in the study participants' activity equaled about 2,200 extra steps a day. The findings were reported in the journal Diabetes Care.

An earlier study found that healthy lifestyle changes may work better than the prescription medication metformin (Glucophage), when it comes to preventing metabolic syndrome. Metabolic syndrome is a combination of risk factors including abdominal obesity, insulin resistance, high triglycerides, and hypertension.

The following are precautions for all people with diabetes, whether type 1 or 2:

Because people with diabetes are at higher than average risk for heart disease, they should always check with their doctors before starting a demanding exercise program. For best and fastest results, frequent high-intensity (not high-impact) exercises are best for people who are cleared by their doctor. For people who have been sedentary, or have other medical problems, lower-intensity exercises are recommended, using programs the patients designed with their doctors.
Strenuous strength training or high-impact exercise is not recommended for people with uncontrolled diabetes. Such exercises can strain weakened blood vessels in the eyes of patients with retinopathy (a common diabetic complication). High-impact exercise may also injure blood vessels in the feet.

Patients who are taking medications that lower blood glucose, particularly insulin, should take special precautions before starting a workout program.

Glucose levels swing dramatically during exercise. People with diabetes should monitor their levels carefully before, during, and after workouts.
Patients should probably avoid exercise if glucose levels are above 300 mg/dL or under 100 mg/dL.
To avoid hypoglycemia (low blood sugar), people with diabetes should inject insulin in sites away from the muscles they use the most during exercise.
People with diabetes should drink plenty of fluids. Before exercising, they should avoid alcohol, which increases the risk of hypoglycemia.
Insulin-dependent athletes may need to decrease insulin doses, or take in more carbohydrates, prior to exercise. However, they may need to take an extra dose of insulin after exercise. Stress hormones released during exercise may increase blood glucose level (in people without diabetes, insulin is released to control this increase). People with diabetes must regularly test their blood sugar, and take any medications as instructed by their doctor.

A person with diabetes must regularly check their blood sugar (glucose) level.

Exercise's Effects on Bones and Muscles

Exercise is critical for strong muscles and bones. Muscle strength declines as people age, but studies report that when people exercise they are stronger and leaner than others in their age group.

Exercise helps kids lower their risk of chronic pain in the future. Research has shown that it helps them prevent back and neck pain. The more flexible men are as teenagers, the lower their risk of neck tension in the future, according to a study published in the February 2006 British Journal of Sports Medicine. The same report found that women who had the greatest endurance strength as teenagers had a lower risk of tension neck than those with lower teenager endurance strength. However, men with the greatest endurance strength had higher rates of knee injuries later on.

Joints are complex structures. They are designed to bear weight and move the body. Above the knee is the femur (thigh bone). Below the knee is the tibia (shin bone) and fibula. The kneecap is also called the patella. It rides on top of the lower portion of the femur and the top portion of the tibia. The muscles and ligaments connect these bones and the space between them is cushioned by fluid-filled capsules (synovia) and cartilage. When you exercise, the muscles pull on the bones, strengthening them. The range of motion of a joint represents how far it can be flexed (bent) and extended (stretched).

Joints require motion to stay healthy. Long periods of inactivity cause the arthritic joint to stiffen and the adjoining tissue to weaken. A moderate exercise program that includes low-impact aerobics, power, and strength training has benefits for osteoarthritic patients, even if exercise does not slow down the disease progression. Many patients who start an exercise program report less disability and pain. They are also better able to perform daily chores, and remain independent longer than their inactive peers. Older patients and those with medical problems should always check with their doctor before starting an exercise program.

Click the icon to see an image of osteoporosis.

The following are useful exercises for osteoarthritis patients:

Strengthening exercises builds muscle strength. Some experts encourage patients to emphasize strengthening leg muscles as a first treatment step, even before using pain relievers. They fear that patients who rely on painkilling drugs may overuse knees, which do not have strong enough muscle tissue to protect the joints from further damage. Strengthening the thigh muscles is certainly protective for those who have not developed osteoarthritis.
Range-of-motion exercises increase the amount of movement in a joint and muscle. The best examples are yoga and tai chi, which focus on flexibility, balance, and proper breathing. In one 2001 study, older adults who practiced the gentle movement, breathing, and meditation exercises of tai chi for 10 weeks reported less pain than their peers who did not learn the technique.
Low-impact aerobic workouts help stabilize and support the joints. Cycling and walking are beneficial, and swimming or exercising in water is highly recommended for people with arthritis. Patients with arthritis should avoid high-impact sports, such as jogging, tennis, and racquetball.
Some researchers are now focusing on "power" training, which involves improving the muscle's ability to move more rapidly against resisting forces, such as gravity. For example, such training helps people stand up or climb stairs more quickly. Muscle power declines more rapidly than muscle strength, and may be particularly important in older people.

Exercise is very important for slowing the progression of osteoporosis, and extremely important for reducing the risk of falling, which causes fractures. Falls are one of the leading causes of death in people over the age of 65. Exercise helps build balance and flexibility, which reduces the risk of falling.

Specific exercises may be especially helpful for reducing the risk of fractures:

Weight-bearing exercise is very beneficial for bones in people of all ages, even older people. This approach applies tension to muscle and bone, and the body responds to this stress by increasing bone density, in young adults by as much as 2 - 8% a year. Careful weight training can also be very beneficial for elderly people, particularly women. In addition to improving bone density, weight-bearing exercise reduces the risk of fractures by improving muscle strength and balance, thus helping to prevent falls.
Regular brisk long walks improve bone density and mobility. In one 2002 study, for example, older women reduced their risk of hip fracture by over 40% by working out just four hours a week.
Exercises specifically targeted to strengthen the back can be beneficial in improving posture, and may even reduce kyphosis (hunchback) in people with osteoporosis.
Low-impact exercises, particularly yoga and tai chi, which improve balance and strength, have been found to decrease the risk of falling. In one study, tai chi reduced this risk by almost half.

Click the icon to see an image of the bone-building exercise.

Note on Female Athlete Triad. Some young female athletes who exercise very intensely, and are subject to intense pressure to remain thin, are at risk for the female athlete triad. This syndrome is a combination of three disorders -- an eating disorder, loss of menstrual periods, and osteoporosis.

People who do not exercise regularly face an increased risk for low back pain, especially during times when they suddenly have to perform stressful, unfamiliar activities. These activities may include shoveling, digging, or moving heavy items. Although no definitive studies have been done to prove the relationship between lack of exercise and low back pain, sedentary living is probably a primary nonmedical cause contributing to this condition.

Lack of exercise leads to the following conditions that may threaten the back:

Muscle inflexibility can restrict the back's ability to move, rotate, and bend.
Weak stomach muscles can increase the strain on the back and can cause an abnormal tilt of the pelvis (hip bones).
Weak back muscles may increase the load on the spine and the risk of disk compression.
Obesity puts more weight on the spine and increases pressure on the vertebrae and disks. Studies report only a weak association between obesity and low back pain, however.

Benefits for Chronic Back Pain. People in with sudden and severe back pain should not exercise. Exercise plays a very beneficial role in relieving chronic back pain, however. In one study, patients with back pain lasting for an average of 18 months were assigned eight 1-hour exercise sessions over 4 weeks. They showed greater improvement in nearly every area, including reduced pain, compared to patients who did not exercise.

Exercise should be considered as part of a broader program to return to normal home, work, and social activities. In this way, the positive benefits of exercise not only affect strength and flexibility but they also alter and improve the patients' attitudes toward their disability and pain.

Repetition is the key to increasing flexibility, building endurance, and strengthening the specific muscles needed to support the spine. Some exercise programs used for prevention or treatment of chronic low back pain include the following:

Low-impact Aerobic Exercises: Low-impact aerobic exercises, such as swimming, bicycling, and walking, can strengthen muscles in the abdomen and back without over-straining the back. Programs that use strengthening exercises while swimming may be a particularly beneficial approach for many patients with back pain. In one study, for example, pregnant women who engaged in a water gymnastics program had less back pain, and were able to continue working longer.
Lumbar Extension Strength Training: Exercises called lumbar extension strength training are proving to be effective. Generally, these exercises attempt to strengthen the abdomen, and improve lower back mobility, strength, and endurance. They also enhance flexibility in the hip and hamstring muscles, and in the tendons at the back of the thigh.
Yoga, Tai Chi, and Chi Kung: These exercises combine low-impact physical movements and meditation. They are based on principles of disciplining the mind to achieve a physical and mental balance, and can be very helpful in preventing recurrences of low back pain. In one study of Pilates, an exercise practice that uses yoga principles, the exercises were helpful in a woman with progressive and disabling severe low back pain resulting from early scoliosis. This approach deserves further research.
Flexibility Exercises: Whether flexibility exercises alone offer any significant benefit for chronic back pain is uncertain. One study suggested that any benefits derived from flexibility exercises are lost unless the exercise programs are sustained.
Retraining Deep Muscles: Studies are finding a link between low back pain and poor motor control of deep muscles in the back and trunk. According to these studies, contraction exercises specifically designed to retrain these muscles may be effective for patients with both acute and chronic pain.

It is important for any person who has low back pain to have an exercise program guided by professionals who understand the limitations and special needs of back pain and who can address individual health conditions. One study indicated that patients who planned their own exercise did worse than those in physical therapy or doctor-directed programs.

Hazardous Effects on the Back. Improper or excessive exercise can also cause back pain.

Exercise's Effects on the Lungs

Patients with chronic lung problems have difficulty exercising. Shortness of breath is a major limitation in most patients, but in about a third, muscle fatigue is an even greater problem. Although exercise does not improve lung function, training helps many patients with chronic lung disease by strengthening their limb muscles, thus improving endurance and reducing breathlessness.

In people who already have colds, exercise has no effect on the illness' severity or duration. People should avoid strenuous physical activity when they have fevers, muscle aches, or other symptoms of a widespread viral illnesses.

Long-term exercise may help control asthma and reduce hospitalization. One 2000 study found that aerobic exercise improves breathing capacity and function in patients with mild asthma. People with asthma who enjoy running should probably choose an indoor track, to avoid pollutants. Swimming is particularly excellent for people with asthma. Yoga practice, which uses both stretching, breathing, chest expansion, and meditation techniques may have specific benefits that include stress reduction as well as airway opening. One study reported that two thirds of patients who practiced yoga regularly were able to reduce or eliminate their asthma medications.

Exercise-Induced Asthma. About 40 - 90% of asthma cases are exercise-induced asthma (EIA), in which exercise triggers coughing, wheezing, or shortness of breath. It occurs most often in children and young adults and during intense exercise in cold dry air. EIA is triggered only by exercise. Unlike allergic asthma, there is no long-term increase in airway activity. People who only have EIA do not require long-term maintenance therapy. The warm-up and cool-down periods, which are important for any exercise regimen, may help reduce EIA events. A study of military recruits found that exercise-induced asthma attacks did not hinder their ability to perform or train, suggesting that EIA is not a reason to exclude people from physically demanding occupations.

Exercise-induced asthma is distinct from allergic asthma in that it does not produce long-term increase in airway activity. People who only experience asthma when they exercise may be able to control their symptoms with preventive measures such as warm-up and cool-down exercises.

Walking is the best exercise for people with emphysema. Patients should try to walk three to four times daily for 5 - 15 minutes each time. Devices that assist ventilation may reduce breathlessness that occurs during exercise.

Inspiratory muscle training involves exercises and devices that make inhaling (breathing in) more difficult, in order to strengthen breathing muscles. In a 2001 study, patients who took part in an inspiratory muscle training group improved their breathing, walking capacity, and quality of life. Yoga or martial arts exercises, such as tai chi, which emphasize breathing techniques and balanced movements, may be particularly beneficial for patients with emphysema.

Exercise's Effects on Weight

Exercising helps people reduce their weight, maintain weight loss, and fight obesity. Research has shown that women who regularly exercise but do not change their diet can lose significantly more weight than less active women.

Thirty minutes of moderate-intensity exercise may be adequate to maintain cardiovascular health, but it might not prevent weight gain. Recommendations published in 2003 and 2004 suggest that 45 - 60 minutes of exercise per day is necessary to promote weight loss. Children may need more activity.

Losing significant weight requires both exercise and calorie restriction. In addition, if a person exercises without dieting, any actual weight loss may be minimal because dense and heavier muscle mass replaces fat. Nonetheless, regardless of weight loss, a fit body will look more toned and be healthier.

People who exercise are more apt to stay on a diet plan. Exercise improves psychological well-being and replaces sedentary habits that usually lead to snacking. Exercise may even act as a mild appetite suppressant.

Exercising without dieting still adds health benefits. One study found that overweight but fit people have half the death rate of overweight, unfit people. Research suggests that people who have trained for a long time develop more efficient mechanisms for burning fat and are able to stay leaner.

Lifting weights builds muscle, which burns calories more efficiently than other body tissues.

The following are some suggestions and observations on exercise and weight loss:

The treadmill burns the most calories of standard aerobic machines. It may be particularly effective when used in short multiple bouts during the day. Exercise sessions as short as 10 minutes, which are done frequently (about four times a day), may be the most successful program for obese people.
The more strenuous the exercise, the longer the body continues to burn calories before returning to its resting level. This state of fast calorie burning can last for as little as a few minutes after light exercise, to as long as several hours after prolonged or heavy exercise.
Resistance (strength) training is excellent for replacing fat with muscles. It should be performed two or three times a week.
Fidgeting may be very helpful in keeping pounds off. Regular exercise is certainly the best course, but for people who must sit for hours at work, frequently shifting positions while sitting may have some benefit.
It is important to realize that as people slim down, they burn fewer calories per mile of walking or jogging. The rate of weight loss slows down, sometimes discouragingly so, after an initial dramatic head start using diet and exercise combinations. People should be aware of this trend and keep adding to their daily exercise routine.
Changes in fat and muscle distribution may differ between men and women as they exercise. Men tend to lose abdominal fat (which lowers their risk for heart disease faster than reducing general body fat). Exercise, however, does not appear to have the same effect on weight distribution in women. A study of women who practiced aerobic and strength training showed the training resulted in fat loss in the women's arms and trunk. However, they did not gain muscle tissue in those areas.

Because obesity is one of the risk factors for heart disease, anyone who is overweight must discuss their exercise program with a physician before starting.

Exercise's Effects on Other Conditions

Physical activity makes you healthier. It lowers your risk for cardiovascular disease and reduces bone loss. Physical activity also helps the body use calories more efficiently, which helps you eliminate body fat and lose weight. It also helps you maintain weight loss by increasing your metabolism and reducing your appetite.

A number of studies have indicated that regular exercise may reduce the risk of breast, colon, and possibly prostate cancers.

Studies confirm that exercise significantly reduces the risk of both colon cancer (by up to 50%) and breast cancer (by up to 30%).

A 2006 study found that, though protection from breast cancer may vary among the types of tumor, exercise offered the most marked protection from the more aggressive tumors. A second study, also done in 2006, supported this finding. Several studies also suggested that more intense exercise is more protective against breast cancer. Exercising consistently throughout life gives the best protection. Exercise not only lowers a woman's chance of getting breast cancer, it can help those who have received chemotherapy for the disease fight off fatigue.

While endurance athletes may suffer from stomach problems, low intensity exercise has a marked protective effect against colon cancer, according to studies, including the Nurses Health Study and the American Cancer Society's Cancer Prevention Study II. Furthermore, a 2006 study found that people with colon cancer who exercise reduce their risk of a recurrence.

Exercise also has a beneficial effect on people receiving treatment for prostate cancer. A new study found that aerobic and resistance training significantly reduced fatigue in men undergoing radiation treatments for prostate cancer. Fatigue is a common side effect of such treatments. In this study, 122 patients received supervised aerobic training, resistance training, or neither. At the end of 24 weeks, participants in both exercise groups noted significant improvement in their fatigue symptoms, compared to the control group. Participants in the resistance training group also lost a significant percentage of their body fat.

Endurance athletes often report stomach problems, such as bloating, diarrhea, and gas, even at rest. Experts suggest that moderate regular exercise might reduce the risk for some intestinal disorders. These disorders include ulcers, irritable bowel syndrome, indigestion, and diverticulosis. Older people who exercise moderately may have a lower risk for severe gastrointestinal bleeding.

Patients with end-stage kidney disease who exercise four to five times per week have better survival rates than those who are less active, according to researchers involved in the Dialysis Morbidity and Mortality Wave 2 study. However, the majority of study participants said that severe physical limitations prevented them from exercising so often.

Studies have shown that regular exercise, particularly walking, helps reduce one's risk for memory loss. A 2005 study found that older men who walked less than a mile daily had a 71% higher risk of dementia than those who walked more than two miles a day. A 2006 study found that people older than 65 who exercise regularly had lower risk of developing dementia, particularly Alzheimer's disease. An earlier study found that walking regularly protects women from mental decline. To date, there are no clear explanations for this apparent benefit. A preliminary study in mice suggests that physical activity changes the way brain-damaging proteins are processed in the brain, thus slowing the development of Alzheimer's disease. Aerobic exercise has been linked with improved reaction time, perception, and math skills in people of all ages.

Doctors found that exercise improves the physical and emotional well-being of patients who already have Alzheimer's disease. The patients exercised moderately for as little as 60 minutes each week. Doctors noted patients who exercised were less depressed, wandered away less, suffered fewer falls, and were placed in nursing homes later, compared to patients who did not exercise.

People with existing neurological diseases, such as multiple sclerosis, Parkinson's disease, and Alzheimer's disease, should be encouraged to exercise. Specialized exercise programs that improve mobility are particularly valuable for patients with Parkinson's disease. Patients with neurological disorders who exercise experience less stiffness, as well as reduction in, and even reversal of, muscle wasting. In addition, the psychological benefits of exercise are extremely important in managing these disorders. Exercise machines, aquatic exercises, and walking are particularly useful.

Some research has suggested that exercise may have antidepressant effects. Although there is little strong evidence that exercise can help manage depression, a number of studies have suggested benefits. Research findings include:

Just 30 minutes of brisk exercise three times a week was as effective as medication in relieving symptoms, and reducing relapse, in many patients with mild-to-moderate depression.
Over half of older women with depression that did not respond to medication improved with 10 weeks of exercise. (About a third of women who did not exercise also improved during that time.)
Studies on elderly, depressed patients report modest benefits from exercise, even in those who do not response to antidepressants. Simply participating in a group activity may help improve mood.
Teenagers who are active in sports have a greater sense of well-being than their sedentary peers. The more vigorously they exercise, the better their emotional health.
Physical inactivity is strongly linked to depression in children 8 - 12 years of age.

Specific exercises may be particularly beneficial:

Aerobics. Either brief periods of intense training or prolonged aerobic workouts can raise levels of certain chemicals in the brain. These chemicals -- which include endorphins, adrenaline, serotonin, and dopamine -- produce the so-called runner's high. Weight loss and increased muscle tone can boost self-esteem.

Yoga. Yoga practice, which involves rhythmic stretching movements and breathing, has been found to positively affect mood. It may have clinical potential as a technique for improving and stabilizing mood. A study comparing yoga to aerobic exercise found that men have significantly lower levels of tension, fatigue, and anger after yoga, compared with levels after swimming. Yoga and swimming tended to produce equal benefits in women.

Click the icon to see an image of the benefits of yoga.

Moderate exercise in healthy pregnant women does not increase the risk for miscarriage, preterm labor, or rupture of the membrane. Not exercising increases the risk for complications, including low-birth weight babies. Exercising increases the fetal heart rate, which in turn protects the baby.

Healthy women with normal pregnancies should exercise at least three times a week, being careful to warm up, cool down, and drink plenty of liquids. Many prenatal calisthenics programs are available.

The following are specific exercises that may benefit the pregnant woman:

Swimming and water aerobics may be the best option for most pregnant women. Swimming has special benefits for those with fluid buildup. Water exercises involve no impact, overheating is unlikely, and swimming face down promotes optimum blood flow to the uterus.
Performing yoga exercises under the guidance of informed instructors can be very helpful.
Walking is also beneficial.

To strengthen pelvic muscles, women should perform Kegel exercises at least six times a day. This involves contracting the muscles around the vagina and urethra for three seconds 12 - 15 times in a row.

Experts generally recommend the following precautions for pregnant women who exercise:

Fit women who have exercised regularly before pregnancy may work out intensely as long as the doctor approves and no discomfort occurs.
As a rule for previously sedentary, low-risk expectant mothers, the pulse rate should not exceed 70 - 75% of the maximum heart rate, or more than 150 beats per minute. Any sedentary expectant mother should check with her doctor before starting an exercise program.
According to one study, vigorous exercise may improve the chances for a timely delivery. All pregnant women, however, should avoid high-impact, jerky, and jarring exercises, such as aerobic dancing, which can weaken the pelvic floor muscles that support the uterus.
During exercise, women should monitor their temperature to avoid overheating, a side effect that can damage the fetus. (Pregnant women should also not use hot tubs or steam baths, which can cause fetal damage and miscarriage.)

Note: Strenuous exercise may affect the flavor of breast milk for a short time afterward. Nursing mothers who engage in such activity might want to wait about an hour after exercising before they feed their infant.

Complications

Exercise may lead to injury if not done properly. Always exercise with care.

Competitive running or high-impact aerobics pose a high risk of a number of injuries to the bones and muscle. The effect of high-impact exercise on the back is not entirely clear. Some research suggests that over time, high-impact exercise may increase the risk for degenerative disk disease. A survey of people who played tennis, however, found no increased risk for low back pain or sciatica.

High-impact exercise can also cause dizziness, ringing in the ear, motion sickness, or loss of high-frequency hearing.

Some research further suggests that in people unused to exercise, intense activity increases production of harmful particles in the body called free radicals. These unstable oxygen particles injure muscle tissue. Muscle pain in this case does not occur until 24 - 48 hours after exercise.

Some people have a higher than average risk for injury:

About half of people at any age who participate in competitive running or high-impact aerobics experience minor injuries at least once a year. Young, intensely competitive athletes may be at risk for permanent injury. Studies are mixed over whether intensive high-impact sports in younger people cause long-term degenerative joint disease.
As the number of older people who start exercising increases, there has also been an increase in injuries for this age group. Between 1990 and 1996, injuries from active sports increased by 54% in people age 65 and older.
Women are far more likely than men to suffer knee injuries.
Urinary incontinence affects many female athletes who engage in high-impact exercise.
Tennis players are at high risk for injuries from repetitive force on the shoulder joint.

Preventing High-Impact Injuries. The following may be helpful for preventing injury:

Wear shock-absorbing footwear with weight-dampening inserts.
Combine weight lifting with jumping exercises. This may prevent injury by strengthening hamstrings and improving coordination.
Vary training and alternate easy and harder workouts.
Be careful to warm up, cool down, and stretch. Flexibility is the key to preventing many muscle strains.
Take days off now and then. The risk of injury increases when athletes train more than five times a week.

Because of the association between high-impact exercises and oxidation, some experts suggest eating foods rich in antioxidants, such as vitamins A, C, and E. Such foods, which may protect against damage from free radicals, include many fresh fruits and vegetables.

Treating Minor Injuries. Most mild or moderate injuries respond well to a simple, four-step treatment: rest, ice, compression, and elevation (RICE). This combination works well for both spot injuries and chronic problems. Ice packs, which reduce inflammation and pain, can help new injuries, and can be useful for the first few hours after a chronically injured area is exercised. How much or how long to compress the injury is unclear.

Evidence suggests that early movement is helpful, although taping or bracing in people with a recurrent ankle sprain is known to be protective. It may not be helpful in those without a previous ankle injury.

Minor injuries like sprains may be treated at home if broken bones are not suspected. The acronym RICE can help you remember how to treat minor injuries: "R" stands for rest, "I" is for ice, "C" is for compression, and "E" is for elevation. Pain and swelling should decrease within 48 hours. Gentle movement may help, but pressure should not be put on a sprained joint until pain is completely gone. This can take up to a few weeks.

Heat, ultrasound, whirlpool, and massage may speed healing if applied a day or two after the initial injury or for warm-up before another workout session.

Some young female athletes who exercise very intensely, and are subject to intense pressure to remain thin, are at risk for a syndrome known as the female athlete triad. This combination of symptoms includes loss of menstruation, eating disorders, and osteoporosis. Eating disorders among young female athletes are estimated at 15 - 62%. Women at higher risk include ballet dancers, gymnasts, and divers. Continued intense exercise causes a stress response in which estrogen (the primary female hormone) is lost. Estrogen loss can lead to infertility and osteoporosis. Iron loss and anemia may also be a problem in women who exercise frequently, even at moderate intensity. A doctor should be consulted for any of these concerns.

Incorrect movements can literally cause mechanical problems in the muscles. These problems are usually the result of improper exercise instruction, and lack of attention. A single jerky golf swing, or the incorrect use of exercise equipment (especially free weights, nautilus, and rowing machines), can cause serious back injuries.

Between 30 - 70% of cyclists experience low back pain. Pain may be improved by adjusting the angle of the bicycle seat.

Everyone should drink lots of fluid during intense exercise. Thirst is often a poor indicator of dehydration in people who exercise, particularly older people. During a tough workout in a hot environment, the body can lose two liters of fluid per hour through sweat.

Anyone who exercises intensely should take the following precautions:

Drink 6 - 8 ounces of fluid about 15 minutes before a workout, and then pause regularly during exercise to drink more.
Water is the best choice for replenishing body fluids. Glucose-sodium-potassium solutions, the so-called "sports drinks," which promise instant energy, appear to be no better than water at improving endurance during prolonged intense running.
Caffeinated beverages like coffee and soft drinks give short bursts of energy, but can actually cause fluid loss. Caffeine before a workout has been shown to temporarily raise blood pressure, and reduces blood flow to inactive limbs.

Contrary to popular belief, drinking fluids will not cause cramps. Drinking enough, in fact, helps prevent the painful involuntary muscle spasms that sometimes occur during exercise.

Overheating, or hyperthermia, can be a problem with hard exercise, or when working out in hot weather. Overheating can cause mild to life-threatening conditions. Heat exhaustion, a moderate form of hyperthermia, is characterized by the following symptoms:

Lightheadedness, nausea, headache, hyperventilation, fatigue, and loss of concentration
A high temperature (above 103° F), possibly accompanied by complaints of chills and clammy skin

Individuals should rest in a cool, dry place, drink plenty of fluids, and bring down their body temperature with ice packs pressed against the skin.

Heatstroke. Heatstroke is the most dangerous complication of hyperthermia. The victim may suddenly stop sweating, after which symptoms such as altered consciousness, seizures, and even coma may quickly follow. Heat stroke is a medical emergency and requires immediate cooling of the victim in an ice-water bath or with ice packs. One study suggests that risk for serious complications from exercising in high temperatures may persist as late as the following day, even if the weather has cooled down.

Click the icon to see an image of the dangers of heatstroke.

Precautions are also necessary in cold weather. When exercising in winter dress in layers, including gloves and socks, which create insulated air pockets that trap heat. In cold weather, wear shoes with less ventilation than those worn in the summer. Fingers, toes, ears, and nose are most susceptible to frostbite. Frostbite progresses from stinging or aching to numbness. Fingers and toes may become white. Soaking the hands and feet in warm water can help, but only once there is no risk of refreezing, since a second bout of frostbite after thawing can quicken tissue damage.

Hypothermia can be life-threatening and can occur even after long exposure to temperatures that are above freezing. The condition is characterized by extreme fatigue, mental confusion, apathy, and a lack of coordination. The victim should be warmed as soon as possible with blankets, body heat, and warm fluids.

Motivation

Motivation, or a lack thereof, is one reason many people stop exercising. Here are some tips for avoiding burnout:

Think of exercise as a menu rather than a diet. Choose a number of different physical activities that are personally enjoyable such as sports, dancing, or biking. Although experts say you should get 30 minutes of aerobic exercises at least five times a week, those times can be divided into shorter periods -- such as 10 minute sessions. In addition, people can achieve health benefits from other exercise programs, including weight training, yoga, or tai chi.
Stick to a prepared schedule and record progress.
Develop an interest or hobby that requires physical activity.
Adopt simple routines such as climbing the stairs instead of taking the elevator, walking instead of driving to the local newsstand, or canoeing instead of zooming along in a powerboat.
Try cross training (regularly switching from one type of exercise to another). Studies suggest it is more beneficial than focusing only on one form of exercise.
Exercise with friends.
Join a gym or take classes. Many affordable programs are available.
For those who can afford them, personal trainers can be very helpful and are available in many gyms and exercise clubs. Personal trainers without any connection to a well-reputed gym or fitness club should be certified by a major fitness organization, such as the Aerobics and Fitness Association of America (AFAA) or the American Council on Exercise.
Exercise videos may also be helpful, but people should be sure they are suited to their individual age and health needs, and bear the seal of the AFAA.
Consider getting a dog. A study in the February 2006 American Journal of Preventive Medicine found that dog owners in Canada walk almost twice as much as those who don’t own a dog. Regular walking is a good way to improve health.

Differences in Motivation Between Men and Women. Motivation factors may differ by gender, and women appear to have a harder time. In one study, weight loss was the greatest motivator to exercise for women, and muscle tone was the primary motivator for men. Unfortunately, effects on appearances may take a long time to show, discouraging people from continuing an exercise program even though their health is improving.

Overweight among children and adolescents has now become an epidemic in the United States. Experts say that children should be vigorously active for at least 20 - 60 minutes 3 - 5 days a week. Parents and schools must be imaginative and rigorous in encouraging children to exercise.

Role of Parents. Parents must make conscious efforts to limit sedentary activities, and to encourage physical ones for their children. This includes monitoring the time children spend on the computer, in front of the TV, or playing video games. Parents should suggest different forms of entertainment. Even children who aren't interested in joining a Little League team may enjoy a round of catch with their parents, walking in the park, or swimming in a local lake.

Role of Schools. Early school physical education programs can make a significant difference and the earlier these routines are learned, the more likely they will be carried forth into a healthy adulthood. Schools should emphasize team cooperation or individual improvement and self-mastery. Studies have shown that people tend to give up more quickly and feel less competent if their perceptions of success are based only on comparison to their peers.

People mature at different rates, and there seems to be a genetic component to coordination, strength, speed, and one's response to resistance exercise. Nonetheless, everyone should strive to be as fit as they possibly can, given their strengths and limitations.

The decision to adopt a healthier behavior -- whether it's more exercise, weight loss, or quitting smoking -- is not as simple as just deciding to do it. Behavior change expert James Prochaska and his colleagues outlined a theory, which has been supported by numerous studies, showing that people cycle through a variety of stages before a new behavior is successfully adopted over the long term. It may help you to understand how this works. As you read the description of each stage -- specifically as it relates to exercise -- you may find yourself nodding and saying to yourself, "Yes, that's me!"

Stage 1: Pre-Contemplation. People at this stage have no plans or desire to exercise. They aren't even considering exercising. They are generally unaware of the specific benefits that exercise can bring -- exercise may seem more like a hassle than something worth doing. Or, they may simply have "failed" in the past and have given up.

There's no point in talking about how to start an exercise program if you are at this stage. Instead, it is important to think about how exercise might be good for you personally -- by helping you to lose weight, feel better, have more confidence, live longer, sleep better, or reduce your stress levels. The benefits must be identified before a person will consider exercise.

If you are at this stage, a good activity is to ask four friends or family members why they exercise. Their answers may show you some real-life benefits, and inspire enough interest to compel you to take the next step.

Stage 2: Contemplation. A person at this stage is thinking, "I think I should probably exercise, but I need help getting started." People at this stage know that exercise is good for them, but it seems like a daunting task or they don't think they can pull it off. Some may have tried and "failed" in the past, but they are still receptive to another go-round.

It's important for people at this stage to consider some of the truths and falsehoods of exercise. For example, it is helpful to know that there are many forms of physical activity to select from, and that you can do your exercising in small chunks. It is not true that exercise has to be painful, or that you either succeed or fail. There is no such thing as "failure" -- people become more or less active at different stages of their lives, and it is never too late to get moving again. And people at this stage should find assurance that an exercise plan can be very simple.

If you are at this stage, a good activity is to write down all the things that you believe make exercise difficult -- and to learn strategies for overcoming or side-stepping those hurdles. People at this stage might benefit from making a pledge, contract, or other commitment that they are going to get more active in the near future. The goal is to get un-stuck by identifying the roadblocks and the ways to overcome these roadblocks. The final goal at this stage is to make a commitment.

Stage 3: Preparation. These folks are primed and motivated. They are ready to give exercise a try. The goal of this stage is to create a specific action plan that takes all factors into account, so that the "launch" is successful. People at this stage need to know how much they should be exercising, their target heart rate, and the types of exercises. They should explore the different kinds of exercises and decide which ones to try.

At this stage, people will evaluate exercise machines and health plans, if that interests them, pick the proper clothing or accessories, and consult a doctor if necessary. They also need to think about how they are going to fit their exercise plans into their daily and weekly schedule.

If you are at this stage, you should also consider some backup plans -- what to do if it rains, or if you don't feel like exercising. That way you are prepared to overcome that hurdle when you encounter it. You should be aware of what to expect realistically at the beginning -- for example, be aware that weight loss takes time, but health benefits begin immediately.

Stage 4: Action! People at this stage have just started exercising. This stage is where the biggest behavior change occurs -- these people have started to exercise but it is not yet a long-term, ingrained habit. This stage requires significant commitment and energy.

If you are at this stage, keep talking to friends and family for inspiration. Review your backup plans. Reward yourself for small achievements. Give yourself notes and reminders to exercise. Having a friend to exercise with can be very helpful as you get through this stage. You want to build and maintain momentum, because exercising gets easier once it is a habit!

Stage 5: Maintenance. The people at this stage have been exercising for at least 6 months. At this point, exercising has started to become a habit. The goal here is to prevent relapse. If you are at this stage, identify ways that you can fine-tune your program. Continue to identify roadblocks and improve your backup plans. Think about what you have found most enjoyable about exercising.

What benefits have you gained? Keep reminding yourself of these perks. If giving yourself a challenge was part of your initial motivation, set new goals and find new challenges. If you risk getting bored with your routine, find ways to vary it. Or maybe you have found a comfortable routine that you enjoy -- if it's working, great! There is no need to change it. You might want to read or learn more about your method of exercising, and develop a deeper level of understanding about it. Soon you'll be a pro!

One point about this theory is that people do not proceed from one stage to another in a simple, step-by-step fashion. They actually cycle or spiral back and forth, so that they may move from stage 1 to 2 to 3, and then back to 2 again. They may stay in maintenance mode for years and then fall back to stage 2. Remember that this is normal -- if you tried exercising in the past and didn't stick with it, don't consider yourself a failure. Just know that it's time to try again!

Resources

http://fitness.gov -- The President's Council on Physical Fitness and Sports
www.ncppa.org --National Coalition for Promoting Physical Activity
www.acefitness.org --American Council on Exercise
www.arthritis.org --The Arthritis Foundation offers tips on exercising with arthritis
www.justmove.org -- Just Move (American Heart Association)

References

Taylor, A.H., Ussher, M., & Faulkner, G. The acute effects of exercise on cigarette cravings, withdrawal symptoms, affect and smoking behaviour: a systematic review. Addiction. 2007;102:534-543.

Kruk J. Lifetime physical activity and the risk of breast cancer: a case-control study. Cancer Detect Prev. 2007;31(1):18- 28.

Tehard B, Friedenreich CM, Oppert JM, et al. Effect of physical activity on women at increased risk of breast cancer: results from the E3N cohort study. Cancer Epidemiol Biomarkers Prev. 2006 Jan;15(1):57-64.

Adams SA, Matthews CE, Hebert JR, et al. Association of physical activity with hormone receptor status: the Shanghai Breast Cancer Study. Cancer Epidemiol Biomarkers Prev. 2006 Jun;15(6):1170-8.

Larson EB, Wang L, Bowen JD et al. Exercise is associated with reduced risk for incident dementia among persons 65 years of age and older. Ann Intern Med. 2006 Jan 17;144(2):73-81.

Meyerhardt JA, Heseltine D, Niedzwiecki D, et al. Impact of physical activity on cancer recurrence and survival in patients with stage III colon cancer: findings from CALGB 89803. J Clin Oncol. 2006 Aug 1;24(22):3535-41.

Slattery ML. Physical activity and colorectal cancer. Sports Med. 2004;34(4):239-52.

Peters HP, De Vries WR, Vanberge-Henegouwen GP et al. Potential benefits and hazards of physical activity and exercise on the gastrointestinal tract. Gut. 2001 Mar;48(3):435-9.

Abbott, RD, White, LR, G. Ross, W, et al. Walking and Dementia in Physically Capable Elderly Men. JAMA. 2004;292:1447-1453

Calton BA, Lacey JV Jr, Schatzkin A, Schairer C, Colbert LH, Albanes D, Leitzmann MF. Physical activity and the risk of colon cancer among women: A prospective cohort study (United States). Int J Cancer. 2006 Feb 17; [Epub ahead of print]

Di Loreto C, Fanelli C, Lucidi P, et al. Make your diabetic patients walk: long-term impact of different amounts of physical activity on type 2 diabetes. Diabetes Care. 2005 Jun;28(6):1295-302.

Mikkelsson LO, Nupponen H, Kaprio J, Kautiainen H, Mikkelsson M, Kujala UM. Adolescent flexibility, endurance strength, and physical activity as predictors of adult tension neck, low back pain, and knee injury: A 25 year follow up study. Br J Sports Med. 2006 Feb;40(2):107-13.

Brown SG, Rhodes RE. Relationships among dog ownership and leisure-time walking in Western Canadian adults. Am J Prev Med. 2006 Feb;30(2):131-6.

Simons R, Andel R. The effects of resistance training and walking on functional fitness in advanced old age. J Aging Health. 2006 Feb;18(1):91-105.

Review Date:
4/30/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

High blood pressure

FitSugar — Wed, 08 Oct 2008 17:35:08 -0700

In This Report

Highlights
Introduction
Diagnosis
Causes
Risk Factors
Complications
Symptoms
Treatment
Lifestyle Changes
Medications
Classes of Medications
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approval

In 2007, the FDA approved a new type of high blood pressure drug. Aliskiren (Tekturna) blocks renin, a kidney enzyme that is associated with blood pressure regulation. Aliskiren can be taken alone or in combination with other blood pressure drugs, but it should not be used during pregnancy.

Drug Concerns

ACE inhibitors should never be taken during the second or third trimesters of pregnancy. An important 2006 New England Journal of Medicine study extended these concerns by reporting that ACE inhibitors may cause major heart birth defects during the first trimester. Although this research is still preliminary, the FDA and the American Heart Association now recommend that women who are pregnant or considering becoming pregnant switch to another type of blood pressure drug.
Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk of developing high blood pressure in men, suggests a 2007 Archives of Internal Medicine study. Previous research indicated that these non-prescription painkillers increase high blood pressure risk in women.

Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

The ALLHAT trial has been the most important long-running clinical study for evaluating the effects of high blood pressure medications. One of its most critical findings established the importance of thiazide-type diuretics as first-line treatment for high blood pressure. Recent trial results indicate:

Diuretics are very helpful for preventing heart failure in patients with high blood pressure. In a 2006 Circulation study, diuretics outperformed ACE inhibitors and calcium channel blockers in reducing heart failure risk.
Thiazide-type diuretics may slightly increase the risk of developing diabetes more than other drug classes but their blood pressure-lowering benefits outweigh the risks, according to a 2006 Archives of Internal Medicine study. The study found that all types of blood pressure medications increase blood sugar levels and diabetes risk.

Introduction

High blood pressure, also called hypertension, is elevated pressure of the blood in the arteries. Hypertension results from two major factors, which can be present independently or together:

The heart pumps blood with excessive force
The body's smaller blood vessels (known as the arterioles) narrow, so that blood flow exerts more pressure against the vessels' walls

Blood pressure is the force applied against the walls of the arteries as the heart pumps blood through the body. The pressure is determined by the force and amount of blood pumped and the size and flexibility of the arteries.

Although the body can tolerate increased blood pressure for months and even years, eventually the heart may enlarge (a condition called hypertrophy), which is a major factor in heart failure.

Click the icon to see an image of hypertrophic cardiomyopathy.

Such pressure can also injure blood vessels in the heart, kidneys, the brain, and the eyes.

Two numbers are used to describe blood pressure: the systolic pressure (the higher and first number) and the diastolic pressure (the lower and second number). Health dangers from blood pressure may vary among different age groups and depending on whether systolic or diastolic pressure (or both) is elevated. A third measurement, pulse pressure, may also be important as an indicator of severity.

Blood pressure is measured in millimeters of mercury (mm Hg). According to current adult guidelines, blood pressure is categorized as normal, prehypertensive, and hypertensive (which is further divided into Stage 1 and 2, according to severity). People in normal health should have a blood pressure reading of 120/80 mm Hg or less. High blood pressure is generally considered to be a blood pressure reading greater than or equal to 140 mm Hg (systolic) or greater than or equal to 90 mm Hg (diastolic). Blood pressure readings in the prehypertension category (120-139 systolic or 80-89 diastolic) indicate an increased risk for developing hypertension.

Current guidelines for children are based on percentile ranges for a child’s body size. Hypertension is defined as average systolic and diastolic readings that are greater than the 95th percentile for gender, age, and height on at least three occasions. Prehypertension in children is diagnosed when average systolic or diastolic blood pressure levels are at least in the 90th percentile but less than the 95th percentile. For adolescents, as with adults, blood pressure readings greater than 120/80 are considered prehypertensive. Increasing rates of childhood obesity have lead to higher than average blood pressure levels in children.

American expert groups recommend treating any blood pressure above normal. Some experts are concerned, however, that such guidelines may unnecessarily increase the use of anti-hypertensive drugs. It is important that patients establish a relationship with a doctor whom they trust, to help them determine individual blood pressure goals and treatment regimens. For some patients, a decrease of a few points in blood pressure may not be worth the side effects caused by higher doses of anti-hypertensive drugs.

Systolic Blood Pressure. The systolic pressure (the first and higher number) is the force that blood exerts on the artery walls as the heart contracts to pump out the blood. High systolic pressure is now known to be a greater risk factor than diastolic pressure for heart, kidney, and circulatory complications and for death, particularly in middle-aged and elderly adults. The wider the spread between the systolic and diastolic measurements, the greater the danger.

Elevated systolic pressure may pose a significant danger for heart events and stroke events even when diastolic is normal -- a condition called isolated systolic hypertension. Isolated systolic hypertension is the most common form of hypertension in people older than age 50. In one study, it comprised 87% of hypertension cases in people between ages 50 and 59.

Diastolic Blood Pressure. The diastolic pressure (the second and lower number) is the measurement of force as the heart relaxes to allow the blood to flow into the heart. High diastolic pressure is a strong predictor of heart attack and stroke in young adults.

Pulse Pressure. Pulse pressure is the difference between the systolic and the diastolic readings. It appears to be an indicator of stiffness and inflammation in the blood-vessel walls. The greater the difference between systolic and diastolic numbers, the stiffer and more injured the vessels are thought to be. Although not yet used by doctors to determine treatment, evidence suggests that it may prove to be a strong predictor of heart problems, particularly in older adults. Some studies suggest that in people over 45 years old, every 10 mm Hg increase in pulse pressure increases the risk for stroke rises by 11%, cardiovascular disease by 10%, and overall mortality by 16%. (In younger adults the risks are even higher.)

Click the icon to see an animation about blood pressure.

Some experts categorize hypertension into the following types:

Essential Hypertension. Essential hypertension is also known as primary or idiopathic hypertension. About 90% of all high blood pressure cases are this type. The causes of essential hypertension are unknown but are based on complex processes in all major organs and systems, including the heart, blood vessels, nerves, hormones, and the kidneys.

Secondary Hypertension. Secondary hypertension comprises about 5% of high blood pressure cases. In this condition, the cause has been identified.

Isolated Systolic Hypertension. This occurs when systolic hypertension is over 140 mm Hg but diastolic pressure is normal. It is related to arteriosclerosis (hardening of the arteries).

Click the icon to see an image of atherosclerosis.

Pregnancy Induced Hypertension. This condition occurs during pregnancy if blood pressure increases by more than 15 mm Hg above normal.

White Coat Hypertension. This form of hypertension is elevated blood pressure that occurs only during a visit to the doctor's office, but not at home. It is a factor in about 20% of patients with mild hypertension. Although previously considered a relatively harmless condition, research now suggests that white-coat hypertension shares certain features with essential hypertension. Studies have even suggested that white-coat hypertension actually may pose a risk for future heart problems, although the increased danger appears to be small compared with the risk in those with steady mild hypertension.


Blood Pressure Category	Ranges for Most Adults (systolic/diastolic)
Normal Blood Pressure (systolic/diastolic)	Systolic below 120 mm Hg Diastolic below 80 mm Hg
Prehypertension (Formerly Normal to High-Normal Blood Pressure)	Systolic 120 - 139 mm Hg Diastolic 80 - 89 mm Hg (NOTE: 139/89 or below should be the minimum goal for everyone. People with diabetes or chronic kidney disease should strive for 130/80 or less.)
Mild Hypertension (Stage 1)	Systolic 140 - 159 mm Hg Diastolic 90 - 99 mm Hg
Moderate to Severe Hypertension (Stage 2)	Systolic over 160 mm Hg or Diastolic over 100 mm Hg
Note: If one of the measurements is in a higher category than the other, the higher measurement is usually used to determine the stage. For example, if systolic pressure is 165 (Stage 2) and diastolic is 92 (Stage 1), the patient would still be diagnosed with Stage 2 hypertension. It should be strongly noted that a high systolic pressure compared to a normal or low diastolic pressure should be a major focus of concern in most adults.

Diagnosis

Most physical exams include a blood pressure measurement. Patients should not smoke or drink caffeinated beverages within 30 minutes before their blood pressure measurement.

The standard instrument used to measure blood pressure is called a mercury sphygmomanometer. Measurements are given as units of mercury, which has filled the central column in standard sphygmomanometers for years. (Some people view the mercury sphygmomanometer as an environmental health hazard, but modern devices are designed to prevent mercury spillage.)
An inflatable cuff with a meter attached is placed around the patient's arm over the artery while the patient is seated. The inflated cuff briefly interrupts the flow of blood in the artery, which then resumes as the cuff is slowly deflated.
The person taking the blood pressure listens through a stethoscope for so-called Korotkoff sounds, which first appear as blood begins to flow through the artery and then change in tone and volume as the cuff is deflated.
If a first blood pressure reading is above normal, the health professional may take two or more measurements separated by 2 minutes with the patient sitting or lying down. Another measurement may be taken after the patient has been standing for 2 minutes.

To measure blood pressure, your doctor uses an instrument called a "sphygmomanometer," more often referred to as a blood pressure cuff. The cuff is wrapped around your upper arm and inflated to stop the flow of blood in your artery. As the cuff is slowly deflated, your doctor uses a stethoscope to listen to the blood pumping through the artery. These pumping sounds register on a gauge attached to the cuff. The first pumping sound your doctor hears is recorded as the systolic pressure, and the last sound is the diastolic pressure.

Although this test has been used for more than 90 years, it is not completely accurate or sensitive. The following factors can cause a falsely low pressure reading:

An arm cuff that is too wide
Recent exercise
Not smoking for a while after heavy, long-term smoking

Falsely high pressure can result from:

An arm cuff that is too small
Talking during the test
Recently consuming foods or beverages (such as coffee) that raise blood pressure

Office blood pressure readings taken by a doctor are more likely to be higher than readings measured at home. This so-called white-coat hypertension requires additional readings by a nurse or by the patient. Home monitoring improves the accuracy of a simple office measurement. An average of all the measurements will be considered in the diagnosis of hypertension. If high normal or high blood pressure persists, further tests should be performed to determine if the organs are affected.

Other Blood-Pressure Monitors. Alternative pressure-measuring aneroid and electronic devices are available. Aneroid instruments are round, compass-like devices that use a metal spring to measure blood pressure and are often used by doctors. Electronic devices are typically used for home monitoring.

Monitoring Equipment. A number of home tests are available for checking blood pressure between doctor visits. A doctor may loan a patient a portable unit that records blood pressure during a full day's activity. This test, known as ambulatory monitoring, is particularly useful for those who experience wide blood pressure swings, such as those who have white-coat hypertension or show resistance to drug therapy. According to one study, accurately measuring blood pressure at home over a full day was a significantly better predictor of cardiovascular risk than standard office-based measurements. To improve clinical outcomes, devices are now available that allow 24-hour ambulatory blood pressure monitoring and electronically store results for analysis by the doctor. It is not clear if their added benefits justify their expense, however.

Cuffs and Stethoscopes. Manual cuffs and stethoscopes are fairly accurate, but they require practice to use. The cuff must be the right size (one size does not fit all). Devices that use a digital readout and a cuff that can be electronically inflated and deflated are proving to be as accurate as a stethoscope.

Blood Pressure Variations at Home. In general, everyone's blood pressure varies in the same way throughout a given day. In monitoring at home, it is important to note these changes:

Blood pressure is usually highest at work.
It drops slightly at home.
It then normally dips to its lowest level during sleep. There are important exceptions. Certain people have a condition called nondipper hypertension, in which blood pressure does not fall at night. Postmenopausal women appear to be at particular risk for this phenomenon, and it may pose a special danger for heart disease and stroke (particularly in older African-American women). It has also been linked to salt-sensitivity and insulin resistance.

Click the icon to see an image of stroke.

Upon waking, pressure in most people typically increases suddenly. In people with severe high blood pressure, this is the highest risk period for heart attack and stroke.

Click the icon to see an image of a heart attack.

Some studies have reported that when patients record and report their own blood pressure, they are unreliable and don't always tell the truth. Despite the difficulties and controversy surrounding this issue, home blood pressure monitoring has been shown to encourage patients to use measures that control their blood pressure and thereby reduce the risk of cardiovascular events.

Click the icon to see an image about monitoring blood pressure.

If blood pressure is elevated, the doctor will check the patient's pulse rate, examine the neck for distended veins or an enlarged thyroid gland, check the heart for enlargement and murmurs, and examine the abdomen and the eyes.

Click the icon to see an image of the thyroid gland.

If hypertension is suspected, the doctor should obtain the following information:

A family and personal medical history, especially incidence of high blood pressure, stroke, heart problems, kidney disease, or diabetes.
Risk factors for heart disease and stroke, including tobacco use, salt intake, obesity, physical inactivity, and unhealthy cholesterol levels.
Any medications being taken.
Any symptom that might indicate so-called secondary hypertension (that is, caused by another disorder). Such symptoms include headache, heart palpitations, excessive sweating, muscle cramps or weakness, or excessive urination.
Any emotional or environmental factors that could affect blood pressure.

If a physical examination indicates hypertension, additional tests may help determine whether it is secondary hypertension or essential hypertension (no other disorder is present) and whether organ damage is present. They include the following:

Blood tests and a urinalysis. (Performed to check for a number of factors, including potassium levels, cholesterol, blood sugar, infection, kidney function, and other possible problems. Measuring blood levels of the protein creatinine, for example, is important for all hypertensive patients in order to determine kidney damage. Higher concentrations may also be an indicator of heart disease.)

An electrocardiogram (ECG).

Click the icon to see an image of an electrocardiogram.

An exercise stress test. This could be important for those with borderline hypertension. Stress-induced blood pressure in such patients has been associated with a risk for left ventricular hypertrophy, a serious complication in which the muscles on the left side of the heart become enlarged. Studies also suggest that an excessive rise in systolic pressure during exercise indicates a risk for coronary artery disease, and stroke.

Click the icon to see an image of blood pressure tests.

Causes

Hypertension is referred to as essential (primary) when the doctor is unable to identify a specific cause. It is by far the most common type of high blood pressure. The causes of this type are unknown but are likely to be a complex combination of genetic, environmental, and other factors.

Genetic Factors. A number of genetic factors or interactions between genes play a major role in essential hypertension. Experts think that the chromosomes (13 and 18) house the genes responsible for blood pressure regulation, although pinning down the range of specific genes involved in hypertension is more difficult.

Abnormalities in the Angiotensin-Renin-Aldosterone System. Genes under intense study are those that regulate a group of hormones known collectively as the angiotensin-renin-aldosterone system. This system influences all aspects of blood pressure control, including blood vessel contraction, sodium and water balance, and cell development in the heart.

Experts believed that this system evolved millions of years ago to protect early humans during drought or stress by retaining salt and water and narrowing blood vessels to ensure adequate blood flow and repair injured tissue. With industrialization, however, this system wreaks havoc on modern humans by intensifying the effects of high-salt diets and sedentary lifestyle. Of particular importance in these harmful responses are the hormone aldosterone and a peptide (a component of proteins) called angiotensin II.

Inherited Abnormalities in the Sympathetic Nervous System. Studies suggest that some people with essential hypertension may inherit abnormalities of the sympathetic nervous system. This is the part of the autonomic nervous system that controls heart rate, blood pressure, and the diameter of the blood vessels.

Insulin Resistance and Type 2 Diabetes. Hypertension is strongly associated with diabetes, both type 1 and type 2. Kidney damage is generally the cause of high blood pressure in type 1 diabetes. Obesity and insulin resistance are the factors associated with hypertension in type 2 diabetes, the more common type. People with type 2 diabetes generally have normal or high levels of insulin, a critical hormone in the metabolism of sugar. However, they are unable to use the insulin, the condition called insulin resistance. Without insulin, blood glucose (sugar) levels rise, the hallmark of diabetes.

Some research indicates that obesity is the one common element linking insulin, type 2 diabetes, and high blood pressure. Obesity is common in both type 2 diabetes and hypertension. Oddly, however, studies have found a stronger association between hypertension and insulin resistance in thin patients as well as overweight people with type 2 diabetes. Some research indicates that insulin resistance may cause sodium retention, a contributor to high blood pressure.

In any case, regardless of the causal connections, people who have insulin resistance or full-blown diabetes plus hypertension have a significantly greater chance for heart attack, kidney disease, and stroke than people who have only high blood pressure.

Obesity. Obesity on its own has a number of possible effects that could lead to hypertension. It may blunt certain actions of insulin that open blood vessels, and it may cause structural changes in the kidney and abnormal handling of sodium. It is also associated with alterations in the systems that regulate blood flow.

Low Levels of Nitric Oxide. The gas nitric oxide can be produced in the body, where it affects the smooth muscle cells that line blood vessels; it helps keep them relaxed, flexible. It may also help prevent blood clotting. Low levels of nitric oxide have been observed in people with high blood pressure (particularly in African-Americans) and may be an important factor in essential hypertension.

Secondary hypertension has recognizable causes, which are usually treatable or reversible.

Medical Conditions. A number of medical conditions can cause secondary high blood pressure:

Kidney disease is the most common cause of secondary hypertension, particularly in older people.
Sleep apnea, a disorder in which breathing halts briefly but repeatedly during sleep, is now highly associated with hypertension. A weak but still higher than normal association with high blood pressure has even been observed in those who snore or have mild sleep apnea. The relationship between sleep apnea and hypertension has been thought to be largely due to obesity, but major studies are finding a higher rate of hypertension in people with sleep apnea regardless of their weight. Treating sleep apnea with a device known as nasal continuous positive airway pressure (CPAP) may have modest benefits blood pressure as well.

CPAP is an airway treatment using slight positive pressure during inhalation to increase the volume of inspired air and to decrease the work of breathing.

Other medical conditions that contribute to temporary hypertension are pregnancy, cirrhosis, and Cushing's disease.

Click the icon to see an image of cirrhosis of the liver.

Medications. Certain prescription and over-the-counter drugs can cause temporary high blood pressure. They include:

Corticosteroids
Acetaminophen (Tylenol)
Nonsteroidal anti-inflammatory drugs (NSAIDs) -- such as ibuprofen (Motrin), naproxen (Aleve), and aspirin -- may cause secondary hypertension as well as other complications. In one important study, women who used an NSAID for 5 or more days a month had a significantly higher risk for hypertension. The more often they used these drugs, the higher the risk. A 2007 study indicated that NSAIDs also increase the risk for hypertension in men. A 2005 study found that NSAIDs increase the risk for kidney failure, and that the risk is significantly greater for all patients with hypertension. Patients who took diuretics along with NSAIDs had 11.6 times the risk of developing acute kidney failure compared to non-NSAID users. The relative risk for calcium channel blockers and NSAIDs was 7.8. The researchers advised that NSAIDs should be used with caution in patients with hypertension or heart failure.
Cold medicines containing pseudoephedrine have also been found to increase blood pressure in hypertensive people, although they appear to pose no danger for those with normal blood pressure.
Oral contraceptives ("the pill") increase the risk for high blood pressure, particularly in women who are older, obese, smokers, or some combination. Stopping the pill nearly always reduces blood pressure, although a recent study suggested that oral contraceptives may produce a small but significant increase in diastolic pressure that persists in some older women who have been off the pill for years.

Alcohol, Cigarettes, and Coffee

An estimated 10% of hypertension cases are caused by alcohol abuse (three or more alcohol drinks a day), with heavier drinkers having higher pressure. Women may be more sensitive than men to the blood pressure effects of alcohol. Moderate drinking (one or two drinks a day) has benefits for the heart and may even protect against some types of stroke. In particular, red wine may have chemicals that help blood pressure.
Smoking. Smoking is a major risk factor. One study reported that smokers have blood pressures up to 10 points higher than nonsmokers.
Caffeine. In healthy people with normal blood pressure, drinking a couple of cups of coffee a day is unlikely to do any harm. A high intake of coffee may be harmful in people with hypertension and may even increase their risk for stroke.

Other Causes of Secondary High Blood Pressure

Stress
Intense workouts (snow shoveling, jogging, speed walking, tennis, heavy lifting, heavy gardening)

Risk Factors

During the last decade, the number of Americans with high blood pressure has increased by 30%. Over 65 million American adults now have high blood pressure, and this condition affects close to 1 billion people worldwide. Less than half of these people are on medication, however, and only about half of this group have their blood pressure under good control with such drugs. Older people are less likely to be treated adequately. The majority of people with high blood pressure have the mild type, but even this condition requires attention.

Age is the major risk factor of hypertension. Blood pressure increases with age in both men and women, and in fact, the lifetime risk for hypertension is nearly 90%. Two-thirds of Americans over age 60 have hypertension. Older women (60 years and above) currently have the highest rates of hypertension, and mortality rates from hypertension are higher in women than in men. Hypertension is also becoming more common in children and teenagers.

Compared to Caucasians, African Americans have 1.8 times the rate of fatal stroke, 1.5 times the risk for fatal heart disease, and 4.2 times the rates of end-stage kidney disease. In general, about 34% of African American men and women have hypertension; it may account for over 40% of all deaths in this group.

The prevalence of high blood pressure among African Americans is among the highest in the world. The rates of hypertension in Hispanic Americans, Caucasians, and Native Americans are about equivalent (ranging from 24 - 27%). The rate is much lower in Asian/ Pacific Islanders (9.7% in men and 8.4% in women). However, nearly 75% of older Japanese American men are hypertensive.

A number of theories have addressed the reasons for this difference:

African Americans may have lower levels of nitric oxide and higher levels of a peptide called endothelin-1 (ET-1) than Caucasians. Nitric oxide keeps blood vessels flexible and open and ET-1 narrows blood vessels.
African Americans have a higher risk for an impaired response to angiotensin (Ang II), which is a peptide important in regulating salt and water balances. African Americans are more likely to be salt-sensitive than other groups.
Social and income disparities and dietary issues may explain many of the differences in blood pressure rates observed between ethnic groups. For example, while African Americans have a disproportionately high rate of hypertension, one study in rural African villages, where diets are rich in fish, reported only a 3% rate of high blood pressure among inhabitants. Another study reported that Caucasian as well as African Americans in the Southeast have a higher incidence of hypertension and stroke than people in other U.S. regions. The Southeast also has a higher rate of obesity, stress, anxiety, and depression, and diets low in potassium and high in salt, all related to a lower socioeconomic level.
African Americans have a higher prevalence of risk factors (cardiovascular disease, obesity, diabetes and kidney disease) that are associated with hypertension.

In any case, hypertension appears to be dangerously undertreated in major minority groups. Inadequately controlled hypertension is the major factor for the higher mortality rate from heart disease among African Americans, and special treatment considerations need to be addressed in this population. A 2003 treatment consensus statement released by the International Society on Hypertension in Blacks (ISHIB) advises that many African Americans may need at least two medications to help lower their blood pressure. The ISHIB's "15 over 10" rule recommends combination therapy for any patient whose blood pressure exceeds their desired goal by 15 mm Hg systolic or 10 mm Hg diastolic.

Obesity. About one-third of patients with high blood pressure are overweight. Even moderately obese adults have double the risk of hypertension than people with normal weights. Moreover, the increase in blood pressure in aging Americans may be due primarily to weight gain. (In other cultures old age does not necessarily coincide with weight gain or high blood pressure.) Children and adolescents who are obese are at greater risk for high blood pressure when they reach adulthood.

Thinness. Interestingly, thin people with hypertension are at higher risk for heart attacks and stroke than obese people with high blood pressure. Experts think that thin people with hypertension are likely to have conditions such as an enlarged heart or stiff arteries that cause the blood pressure to rise and also pose greater dangers to health.

Low Birth Weight. Low birth weight, particularly in girls, has been associated with high blood pressure in both childhood and adulthood. One study suggested that breast-feeding these babies may help reduce this risk. Another study reported high levels of stress hormones in babies with low birth weight, which could increase the risk for high blood pressure later on. Low birth weight is also associated with subsequent obesity, a major contributor to hypertension.

Up to 75% of cardiovascular problems in people with diabetes may be due to hypertension. There are strong biologic links between insulin resistance (with or without diabetes) and hypertension. It is unclear which condition causes the other. Some experts believe angiotensin may be the common factor linking diabetes and high blood pressure. This natural chemical not only influences all aspects of blood pressure control but also interferes with insulin's normal metabolic signaling. People with diabetes or chronic kidney disease need to reduce their blood pressure to 130/80 mm Hg or lower to protect the heart and help prevent other complications common to both diseases. Lowering systolic pressure may be particularly important for people with diabetes.

Spouses. Studies suggest that spouses of people with high blood pressure are at a much higher risk as well. Such findings indicate that dietary and environmental factors play a role in this disease. Some evidence also indicates that higher risk in spouses may be due to people often choosing mates who are similar to them.

Family History and Genetics. Essential hypertension may be inherited in 30 - 60% of cases. According to one study, being a brother or sister of someone with premature coronary artery disease is a greater risk factor for hypertension than having a parent with the disease. A family history of heart disease is considered to be a major risk factor for high blood pressure in adults under age 65.

People who are anxious or depressed may have over twice the risk for high blood pressure than those without these problems.

Mental Stress. Recent evidence confirms the association between stress and hypertension. In one 20-year study, men who periodically measured highest on the stress scale were twice as likely to have high blood pressure as those with normal stress. The effects of stress on blood pressure in women were less clear. Job stress and lack of career success have been specifically linked to high blood pressure in both men and women.

Anxiety. Studies suggest that anxiety is a risk factor for hypertension, particularly in women.

Depression. Mounting evidence suggests that depression has physiological effects that impair the heart and that it contributes to destructive behaviors, such as weight gain, smoking, or alcohol abuse. In one study, those who scored highest on a depression test had about twice the risk of high blood pressure as those with the lowest score. This link was particularly strong in African Americans. Depression was the strongest risk factor in this group.

Blood pressure levels tend to be lowest during the morning and midday hours and highest at the end of the day. Seasonal changes also affect blood pressure, with hypertension increasing during cold months and declining during the summer. Blood pressure readings can vary by as much as 40% depending on the time of day and season.

Complications

Hypertension places stress on several organs (called target organs), including the kidneys, eyes, and heart, causing them to deteriorate over time. High blood pressure contributes to 75% of all strokes and heart attacks. It is particularly deadly in African-Americans.

Research suggests that prehypertension is also a serious risk factor for heart complications. A 2005 study found that people with prehypertension are three times more likely to have a heart attack, and nearly twice as likely to develop coronary artery disease as people with normal blood pressure.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated and controlled by medication, lifestyle changes, or a combination of both.

Malignant hypertension, an emergency condition resulting from untreated primary hypertension, can be lethal.

About two-thirds of people who suffer a first stroke have moderate elevated blood pressure (160/95 mm Hg) or above. Hypertensive people have up to 10 times the normal risk of stroke, depending on the severity of the blood pressure. Hypertension is also an important cause of so-called silent cerebral infarcts, blockages in the blood vessels in the brain that may predict major stroke or progression to dementia over time.

Uncontrolled chronic high blood pressure is also associated with reduced short-term memory and mental abilities. Isolated systolic hypertension may pose a particular risk for complications in the brain. Fortunately, controlling blood pressure with medications can reduce or even prevent memory loss and mental decline due to hypertension. A 2006 study of older men indicated that anti-hypertensive treatment for at least 5 years may help prevent the development of dementia. Other studies suggest that anti-hypertensive drugs may help protect against Alzheimer's disease in people with genetic susceptibility to this disease.

High blood pressure is a major risk factor for heart disease.

Heart Attack. About half of people who suffer their first heart attack have moderate hypertension (160/95 mm Hg) or greater. High blood pressure increases the risk for a heart attack by up to five times, depending on the severity of the hypertension.

Heart Failure. Hypertension precedes heart failure in 75 - 90% of heart failure cases. High blood pressure has various effects that cause the heart to fail, including:

To compensate for increased blood pressure, the heart must work harder to pump blood, and so its muscles thicken (hypertrophy), usually on the left side (left-ventricle dysfunction). These thickened muscles pump inefficiently, and, over time, the force of their contractions weakens. The heart muscles then have difficulty relaxing and filling the heart with blood. The heart begins to fail.

Click the icon to see an image of a hypertensive heart.

The failing heart then triggers a number of hormonal and neurochemical mechanisms to correct imbalances in blood pressure and flow. This response, called remodeling, is helpful in the short run but very destructive and irreversible over time.
As part of the remodeling process, the heart muscle cells elongate. The muscular walls of the heart dilate and become thinner and inefficient. The cells themselves undergo molecular changes that result in calcium loss, a mineral crucial for healthy heart contractions.
The end-result of remodeling is a falling volume of blood pumped to the kidneys; the kidneys retain water and salt in response, increasing fluid buildup in the body.
To make matters worse, the body's arteries narrow in response to a lower blood volume. This constriction forces the heart to work even harder to pump blood through these narrowed vessels, increasing blood pressure and continuing the cycle.

A 2006 analysis of ALLHAT trial data indicated that diuretics are the best first-line high blood pressure medication for preventing heart failure.

Diabetes. High blood pressure, and the medications used to treat it, can increase the risk for developing diabetes. Studies have reported that thiazide diuretics and beta blockers carry a higher risk for causing diabetes than other anti-hypertensive drugs. However, an important 2006 ALLHAT study compared the effects of various drug classes on blood sugar levels and diabetes development. The results suggested that while diuretics may slightly increase diabetes risk more than other types of anti-hypertensive drugs, this effect does not cause worse heart problems. Most experts believe that thiazide diuretics should remain the first choice for high blood pressure treatment, and that the benefit of blood pressure reduction outweighs the risk of diabetes development.

Diabetes-Related Kidney Disease. High blood pressure is strongly associated with diabetic nephropathy (diabetes-related kidney disease). Most patients with type 2 diabetes who show early signs of nephropathy already have high blood pressure. When patients with type 1 diabetes are diagnosed with early nephropathy, on the other hand, they usually have normal blood pressure readings in the doctor's office. A 2002 study using home monitors, however, found that patients with type 1 diabetes often have high systolic blood pressure during sleep -- before development of nephropathy. Home blood pressure monitoring, then, may help identify patients who are at risk for kidney damage due to high systolic pressure.

End-Stage Kidney Disease. High blood pressure causes 30% of all cases of end-stage kidney disease (medically referred to as end-stage renal disease, or ESRD). Only diabetes leads to more cases of kidney failure.

Kidney Cancer. Men with high blood pressure may also have a higher risk of kidney cancer.

High blood pressure can injure the eyes, causing a condition called retinopathy.

Click the icon to see an image of hypertensive retinopathy.

Hypertension also increases the elimination of calcium in urine, potentially leading to loss of bone mineral density, a significant risk factor for fractures, particularly in elderly women. In one study, women with the highest levels of blood pressure lost bone density at nearly twice the rate of those in the lowest range. It is not clear whether this effect occurs in men or in non-Caucasian women.

Sexual dysfunction is more common and more severe in men with hypertension and in smokers than it is in the general population. Many of the drugs that treat hypertension are thought to cause impotence as a side effect. In these cases, it is reversible when the drugs are stopped. More recent evidence suggests, however, that the disease process that causes hypertension is itself the major cause of erectile dysfunction in these men.

Newer anti-hypertensive drugs, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs), are less associated with erectile dysfunction. ARBs, such as losartan (Cozaar), may be particularly effective in restoring erectile function in men with high blood pressure. Sildenafil (Viagra) is successful in achieving erections in almost two-thirds of patients with controlled high blood pressure. Because sildenafil has a shorter half-life and is eliminated more quickly from the body than newer erectile dysfunction drugs, it may be a safer option for men with hypertension. In a 2003 review of safety data, sildenafil did not appear to pose a risk for men who had both high blood pressure and erectile dysfunction.

Severe, sudden high blood pressure in pregnant women is one component of a condition called preeclampsia (commonly called toxemia) that can be very serious for both mother and child. Preeclampsia occurs in up to 10% of all pregnancies, usually in the third trimester of a first pregnancy, and resolves immediately after delivery. Other symptoms and signs of preeclampsia include protein in the urine, severe headaches, and swollen ankles.

This condition may be caused by a failure of the placenta to embed properly in the uterus, which causes it to misconnect with the mother's blood vessels. As a result, the fetus does not receive a sufficient blood supply, and the mother's own blood pressure increases to replace it. The risk for preeclampsia is higher for first births, multiple births, and for very young women (teenagers) and those over age 35. Pre-existing high blood pressure, diabetes, and kidney disease also increase the risk for preeclampsia. There appears to be a genetic component for this condition, so women whose mothers experienced preeclampsia are also at higher risk.

The reduced supply of blood to the placenta can cause low birth weight and eye or brain damage in the fetus. Severe cases of preeclampsia can cause kidney damage, convulsion, and coma in the mother and can be lethal to both mother and child. Evidence also suggests that preeclampsia can lead to increased risks later in life for coronary heart disease and other heart problems.

Women at risk for preeclampsia (particularly those with existing hypertension) may benefit from having an ultrasound of uterine arteries at 20 - 24 weeks of pregnancy, followed (if abnormal) by 24-hour blood pressure monitoring. Blood pressure medications may be required. Delivery is the main cure for preeclampsia. In severe cases, the obstetrician will need to induce pre-term birth.

High blood pressure may increase the risk of developing fibroids, according to data from the Nurses’ Health Study. Tracking women for 10 years, the prospective epidemiologic study found that for every 10 mm/Hg increase in diastolic blood pressure, the risk for developing fibroids increased by 8 - 10%.

Children with high blood pressure should first be treated with lifestyle changes, including weight reduction, increased physical activity, and diet modification. If blood pressure is not controlled with lifestyle changes, drug treatment may be required. Although there are few clinical trials conducted in children, a 2005 study found that the angiotensin receptor blocker losartan was safe and effective in children. Results of studies evaluating outcomes of children with hypertension suggest that early abnormalities, including enlarged heart and abnormalities in the kidney and eyes, may occur even in children with mild hypertension. Children and adolescents with hypertension should be monitored and evaluated for any early organ damage. Secondary hypertension (high blood pressure due to another disease or drug) is more common in children than adults.

Symptoms

Hypertension has aptly been called the "silent killer" because it usually produces no symptoms. Untreated hypertension increases slowly over the years. It is important for anyone with risk factors to have their blood pressure checked regularly and to make appropriate lifestyle changes. Such recommendations are especially important for individuals who have prehypertension or hypertension, a family history of hypertension, are overweight, or are over age 40.

In rare cases (fewer than 1% of all patients with hypertension), the blood pressure rises quickly (with diastolic pressure usually rising to 130 mm Hg or higher), resulting in malignant or accelerated hypertension. This is a life-threatening condition and must be treated immediately. People with uncontrolled hypertension or a history of heart failure are at increased risk for this crisis.

People should call a doctor immediately if these symptoms occur:

Drowsiness
Confusion
Headache
Nausea
Loss of vision

Treatment

Patients with hypertension should work with their doctors to set blood pressure goals based on individual risk factors. Lifestyle and medication programs need to be planned on an individual basis.

Healthy lifestyle changes are imperative for anyone, and are critical for people with even normal blood pressure (120/80 mm Hg) and above. In appropriate patients, aggressive drug treatment of long-term high blood pressure can significantly reduce the incidence of mental decline and death from heart disease and other serious physical effects of hypertension. In people with diabetes, controlling both blood pressure and blood glucose levels prevents serious complications of that disease. Anti-hypertensive drugs may even prevent mental decline, including in people genetically susceptible to Alzheimer's disease. Nevertheless, only slightly over half of patients with hypertension are treated at all, and only a quarter have adequately controlled pressure.

It is not clear when drugs should be started, particularly for people with prehypertension or mild high blood pressure. To help make treatment choices, the U.S. National Heart, Lung, and Blood Institute has created categories (denoted as groups A, B, and C) according to a patient's risk factors for heart disease. Applying these categories to the severity of hypertension helps determine whether lifestyle changes alone or medications are needed.


Risk Groups	Blood Pressure Stages (Systolic/Diastolic)
	Prehypertension (120 - 139/80 - 89)	Mild (Stage 1) Blood Pressure (140 - 159/90 - 99)	Moderate-to-Severe (Stage 2) Blood Pressure (Systolic pressure over 160 or diastolic pressure over 100)
Risk Group A Have no risk factors for heart disease.	Lifestyle changes only. (Exercise and dietary program with regular monitoring.)	Year trial of lifestyle changes only. If blood pressure is not lower at 1 year, add drug treatments.	Lifestyle changes and medications.
Risk Group B Have at least one risk factor for heart disease* (excluding diabetes) but have no target organ damage (such as in the kidneys, eyes, or heart, or existing heart disease).	Lifestyle changes only.	6-month trial of lifestyle changes only. If blood pressure is not lower at 6 months, add drug treatments. Medications considered for patients with multiple risk factors.	Lifestyle changes and medications.
Risk Group C Have diabetes with or without target organ damage and existing heart disease (with or without risk factors for heart disease).	Lifestyle changes and medications.	Lifestyle changes and medications.	Lifestyle changes and medications.

* Risk factors for heart disease include the following: family history of heart disease, smoking, unhealthy cholesterol and lipid levels, diabetes, being over 60 years old.

Lifestyle Changes

Healthy lifestyle changes are an important first step for lowering blood pressure. Current guidelines recommend that people should:

Exercise at least 30 minutes a day
Maintain normal weight
Reduce salt intake
Increase potassium intake
Limit alcohol consumption; however, moderate alcohol consumption (1 – 2 glasses a day) may actually lower the risk for heart attack among men with high blood pressure
Consume a diet rich in fruits, vegetables, and low-fat dairy products while reducing total and saturated fat intake. (The DASH diet is one way of achieving such a dietary plan.)

The DASH diet (Dietary Approaches to Stop Hypertension) is proven to help lower blood pressure. Results are sometimes seen within a few weeks. Restricting sodium improves results. The diet appears to have antioxidant effects and may help lower LDL cholesterol levels, although beneficial HDL levels also decline. This diet is not only rich in important nutrients and fiber but also includes foods that contain far more electrolytes, potassium (4,700 mg/day), calcium (1,250 mg/day), and magnesium (500 mg/day) than are found in the average American diet.

A diet that is effective in lowering blood pressure is called Dietary Approaches to Stop Hypertension (DASH).

DASH diet recommendations:

Limit salt intake to no more than 2,300 mg a day (a maximum intake of 1,500 mg a day is an even better goal).
Reduce saturated fat to no more than 6% of daily calories and total fat to 27% of daily calories. (But, include dairy products that are non- or low-fat. Low-fat dairy products appear to be especially beneficial for lowering systolic blood pressure).
When choosing fats, select monounsaturated oils, such as olive or canola oils.
Choose whole grains over white flour or pasta products.
Choose fresh fruits and vegetables every day. In one study, people who increased their intake of fruits and vegetables experienced a drop in blood pressure after 6 months. Many of these foods are rich in potassium, fiber, or both, possibly helping lower blood pressure.
Include nuts, seeds, or legumes (dried beans or peas) daily.
Choose modest amounts of protein (no more than 18% of total daily calories). Fish, skinless poultry, and soy products are the best protein sources.
Other daily nutrient goals in the DASH diet include limiting carbohydrates to 55% of daily calories and dietary cholesterol to 150 mg. Patients should try to get at least 30 g of daily fiber.

Slight changes to the DASH diet might help further lower blood pressure, as well as improve cholesterol and lipid levels. Researchers reporting in the Journal of the American Medical Association and at the 2005 American Heart Association meeting said that replacing some carbohydrates in the DASH diet with more protein (from plant sources) or monounsaturated fats may help further reduce heart disease risk factors.

A combination of the DASH diet and salt restriction is extremely effective in reducing blood pressure. Reducing sodium may also help protect against heart failure. People with normal blood pressure should consume no more than 2,400 milligrams (about one teaspoon) of sodium each day. People with blood pressure should consume much less. (Patients should consult their doctor on individual recommendations for salt intake.) The following higher-risk groups should take particular measures to restrict salt:

People at Risk for Salt-Sensitivity. About half of people with hypertension have blood pressure that reacts significantly to salt. Such people are known to be salt-sensitive. Groups at particularly high risk for salt-sensitivity include African-Americans, the elderly, and people with diabetes. Even people with normal blood pressure can be salt-sensitive. High-salt diets in anyone who is salt-sensitive may harm the heart, kidneys, and brain and increase the risk for death, regardless of blood pressure. Because testing for salt-sensitivity is not easy, experts recommend that everyone proactively restrict their daily salt-intake.
Overweight People. Overweight individuals may absorb and retain sodium differently from people with normal weights. Reducing sodium can also help lower the risk of heart disease and stroke in people who are overweight. Unfortunately, because overweight people generally consume more calories, they are also likely take in more sodium.
People on Anti-Hypertensive Drugs. Restricting salt also enhances the benefits of many standard anti-hypertensive drugs by reducing potassium loss, and may help protect against kidney disease in patients who are also taking calcium-blocker drugs. A low-salt diet can also increase the chances for being able to stop such medications.

Simply eliminating table and cooking salt can be beneficial. Salt substitutes, such as Cardia, (containing mixtures of potassium, sodium, and magnesium) are available, but they are expensive. In any case, about 75% of the salt in the typical American diet comes from processed or commercial foods, not from food cooked at home, so the benefits of table-salt substitutes are likely to be very modest. Some sodium is essential to protect the heart, but most experts agree that the amount is significantly less than that found in the average American diet. If people cannot significantly reduce the amount of salt in their diets, adding potassium-rich foods might help to restore a healthy balance.

Evidence strongly indicates that a potassium-rich diet can help achieve healthy blood pressure levels, and that potassium supplements can lower systolic blood pressure by 1.8 m Hg and diastolic blood pressure by 1 mm Hg. Some evidence suggests that a potassium-rich diet can reduce the risk of stroke by 22 - 40%. Current expert guidelines support the use of potassium supplements or enough dietary potassium to achieve 3,500 mg per day for people with normal or high blood pressure (who have no risk factors for excess potassium levels). This goal is particularly important in people who have high sodium intake.

The best source of potassium is the fruits and vegetables that contain them. Some potassium-rich foods include bananas, oranges, pears, prunes, cantaloupes, tomatoes, dried peas and beans, nuts, potatoes, and avocados.

Excess potassium can cause abdominal distress, muscle weakness, and, in rare cases, dangerous heart events. Some people should be particularly cautious about excess potassium, including those with conditions, such as diabetes or kidney disease, that increase potassium levels. People who take medications, such as ACE inhibitors or potassium-sparing diuretics that limit the kidney's ability to excrete potassium, should not take potassium supplements.

Smoking. Everyone should quit smoking.

Alcohol. People who drink alcohol should do so in moderation. Men with hypertension should limit their intake to no more than one or two drinks a day, and women and lighter people should drink less.

Caffeine Drinks. Coffee drinking is associated with small increases in blood pressure, but the risk is very small in people with normal blood pressure. People with existing hypertension should avoid caffeine altogether.

Fiber. Fiber supplementation can help reduce blood pressure levels. It may take up to 8 weeks to achieve the maximum benefit.

Folate. Increasing folate (a B vitamin) intake to more than 800 mcg/day can help reduce blood pressure, particularly for younger women (under age 46). Dietary sources of folate include citrus fruits, leafy green vegetables, beans, and grain products. Folate helps to reduce homocysteine levels.

Fish Oil and Omega 3 Fatty Acids. Omega 3 fatty acids (docosahexaenoic and eicosapentaneoic acids) are found in oily fish. Studies indicate that they may have specific benefits for many medical conditions, including hypertension. They appear to help keep blood vessels flexible and may help protect the nervous system. Fatty acids are also available in supplements, but their long-term effects on blood pressure are unknown.

Click the icon to see an image of omega-3 fatty acids

Calcium. Calcium regulates the tone of the smooth muscles lining blood vessels. Studies have found that people who have sufficient dietary calcium have lower blood pressure than those who do not. Hypertension itself increases calcium loss from the body. The effects of extra calcium on blood pressure, however, are mixed, with some even showing higher pressure.

Click the icon to see an image of the sources of calcium.

Magnesium. Some studies reported that magnesium supplements may induce small but significant reductions in blood pressure. No major studies, however, have been done on long-term benefits or risks of magnesium supplements. A major 2001 study on diet found no effect on blood pressure from magnesium intake from foods.

Antioxidant Supplements. Antioxidants are substances that help the body eliminate oxidants, (also called oxygen-free radicals), which are damaging particles produced as part of the body's chemical processes. Some antioxidant supplements, including vitamins C and E and alpha-lipoic acid, are being studied for possible benefits in protecting against hypertension by preventing injury in the blood vessels. Vitamin C may have specific benefits for hypertension by preventing dangerous effects on nitric acid, the substance that keeps arteries flexible.

Click the icon to see an image of vitamin C sources.

Click the icon to see an image of vitamin E sources.

In people who are overweight, even modest reductions in weight, particularly in the abdominal area, can immediately reduce blood pressure. Weight loss, particularly accompanied by salt restriction, may allow patients with mild hypertension, even older people, to safely reduce or go off medications. The benefits of weight loss on blood pressure are long-lasting.

Positive Effects on Blood Pressure. Regular exercise helps keep arteries elastic, even in older people, which in turn ensures blood flow and normal blood pressure. Sedentary people have a 35% greater risk of developing hypertension than athletes.

Experts recommend at least 30 minutes of exercise on most -- if not all-days. In one study, moderate exercise (jogging two miles per day) controlled hypertension so well that more than half the patients who had been taking drugs for high blood pressure were able to discontinue their medication.

Studies have also indicated that yoga and Tai Chi, an ancient Chinese exercise involving slow, relaxing movements, may lower blood pressure almost as well as moderate-intensity aerobic exercises.

High-intensity exercise may not lower blood pressure as effectively as moderate intensity exercise and may be dangerous in people with hypertension.

Negative Effects. Each year an estimated 75,000 heart attacks (5% of all heart attacks) occur after heavy exertion, leading to 25,000 deaths. Older people and those with uncontrolled hypertension or other serious medical conditions should be cautious when exercising. Studies report that older people who begin vigorous exercise are at a slightly higher than average risk for a heart attack during the first year, but over time, regular exercise is likely to be protective.

The following activities may pose particular dangers for high-risk individuals:

Intense workouts (snow shoveling, slow jogging, speed walking, tennis, heavy lifting, heavy gardening). They tend to stress the heart, raise blood pressure for a brief period, and may cause spasms in the arteries leading to the heart.
Competitive sports, which couple intense activity with aggressive emotions.

Effects of Anti-Hypertensive Drugs on Exercise. Certain anti-hypertensive medications, including diuretics and beta-blockers, can interfere with exercise capacity. ACE inhibitors or calcium-channel blockers are the best drugs for active individuals. However, patients who take drugs that interfere somewhat with exercise capability should still adhere to an exercise program and consult a doctor on how best to balance medications with exercise.

Click the icon to see an image about lifestyle changes for hypertension.

Certain sleep disorders, especially sleep apnea, are associated with hypertension. Even chronic, insufficient sleep may raise blood pressure in patients with hypertension, placing them at increased risk of heart disease and death. Stress hormone levels increase with sleeplessness, which can activate the sympathetic nervous system, a strong player in hypertension. Patients who have chronic insomnia or other severe sleep disturbances, (particularly sleep apnea), may want to consult a sleep expert. Patients with hypertension who are habitually poor sleepers should consider long-acting blood pressure medications to help counteract the increase in blood pressure that occurs in the early morning hours.

Improving mood or relieving stress may be helpful. The following studies suggested possible benefits:

Stress reduction programs that use cognitive-behavioral therapy may reduce blood pressure.
Active religious faith was associated with healthy blood pressure levels, possibly indicating the combined benefits of a strong social network and reduced stress from spiritual activities.
A simple relaxation technique called transcendental meditation (TM), which involves silent repetition of a single sound, was associated with lower blood pressure.

Treating stress cannot cure medical problems. Stress management programs are not a substitute for standard medical treatments, but can be a very important component of a lifestyle plan.

Medications

Dozens of anti-hypertensive drugs are available. Most fall into the following categories:

Diuretics rid the body of extra water and salt. Diuretics are usually the first-line treatment for high blood pressure.
Beta-blockers block the effects of adrenaline and ease the heart's pumping action.
Angiotensin converting enzyme (ACE) inhibitorsreduce the production of angiotensin, a chemical that causes arteries to narrow.
Calcium-channel blockers (CCBs) decrease the contractions of the heart and widen blood vessels.
Angiotensin-receptor blockers (ARBs) block angiotensin, another chemical that constricts the arteries.
Vasodilators expand blood vessels.

In about half of patients a single-drug regimen can control mild to moderate hypertension. More severe hypertension often requires a combination of two or more drugs. Each drug has specific benefits, but their effects may vary depending on the individual patient.

One of the most difficult issues that patients face, particularly those with primary hypertension, is that the treatment may make them feel worse than the disease, which usually has no symptoms. Whatever the difficulties, compliance with a drug and lifestyle program is worth the effort. It is very important that patients discuss medication concerns with their doctors. If current blood pressure drugs are causing uncomfortable side effects, the doctor may adjust dosages or combinations.

Patients whose blood pressure has been well-controlled and who are able to maintain a healthy life style may choose to withdraw from medications. They should do so in a step-down manner (gradual reduction) and be monitored regularly. Stopping too quickly can have adverse effects, including serious effects on the heart. The highest success rates are more likely in those who lose weight and reduce sodium intake, in patients who have been treated with a single drug, and in those who have maintained lower systolic blood pressure during treatment. People over 75 years old may have more trouble than younger adults in maintaining normal blood pressure after withdrawal.

Classes of Medications

There are several classes of drugs used to treat hypertension.

Diuretics help the kidneys get rid of excess salt and water. They are the mainstays of anti-hypertensive therapy and are the first drug of choice for most people with hypertension. They are especially helpful for treating the elderly and African-American patients. (African-Americans are more likely to be salt-sensitive, so they respond well to these drugs.) They also work well for patients with diabetes.

Results from the long-term Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), published in the Journal of the American Medical Association in 2005, confirm that thiazide-type diuretics should be the first treatment option for most patients with hypertension. The landmark trial included over 33,000 patients (35% black) with hypertension and at least one other cardiovascular risk factor. Patients were randomized to receive a calcium channel blocker, an ACE inhibitor, or a thiazide-type diuretic.

Results suggested that the diuretic worked just as well as the newer drugs in lowering blood pressure and was more effective in preventing heart failure, heart attack, and stroke. The benefits for the diuretic were even more significant for African-American patients. Other trial results indicated that patients taking the calcium channel blocker had the greatest risk for heart failure, and that the ACE inhibitor was much less effective than the diuretic in lowering blood pressure and preventing stroke in African-American patients.

Diuretic Types and Brands. There are many brands of diuretics. They are generally inexpensive. Some need to be taken once a day, some twice a day. Low doses are usually as effective for lowering blood pressure as higher doses. Diuretics are usually used in combination with other drugs, especially ACE inhibitors and beta blockers.

There are three main types of diuretics:

Potassium-sparing diuretics. These include amiloride (Midamor), spironolactone (Aldactone), and triamterene (Dyrenium).
Thiazide diuretics. These include chlorothiazide (Diuril), chlorthalidone (Hygroton), indapamide (Lozol), hydrochlorothiazide (Esidrix, HydroDiuril), and metolazone (Mykrox, Zaroxolyn).
Loop diuretics. Because loop diuretics act faster than other diuretics it is important to avoid dehydration and potassium loss. Loop diuretics include bumetanide (Bumex), furosemide (Lasix), and torsemide (Demadex).

Benefits of Diuretics. Diuretics can:

Reduce the risk for stroke
Reduce the risk for heart attack and heart failure
Protect against blood clots.

Problems with Diuretics. Loop and thiazide diuretics reduce the body's supply of potassium, which, if left untreated, increases the risk for arrhythmias. Arrhythmias are heart rhythm disturbances that can, in rare instances, lead to cardiac arrest. In such cases, doctors will prescribe lower doses of the current diuretic, recommend potassium supplements, or use potassium-sparing diuretics either alone or in combination with a thiazide. Potassium-sparing drugs have their own risks, which include dangerously high levels of potassium in people with existing elevated levels of potassium or in those with damaged kidneys. However, all diuretics are generally more beneficial than harmful.

Common Diuretic Side Effects:

Fatigue
Depression and irritability
Urinary incontinence
Reduced sexual drive

Beta-blockers help slow heart rate and lower blood pressure. They are usually used in combination with other drugs such as ACE inhibitors and diuretics.

Brands. Propranolol (Inderal), acebutolol (Sectral), atenolol (Tenormin), betaxolol (Kerlone), carteolol (Cartrol), metoprolol (Lopressor), nadolol (Corgard), penbutolol (Levatol), pindolol (Visken), carvedilol (Coreg), and timolol (Blocadren). The drugs may differ in their effects and benefits.

Problems with Beta-Blockers. Evidence presented at the 2005 meeting of the American College of Cardiology suggested that an ACE-inhibitor combined with a calcium channel blocker works just as well as a beta-blocker-diuretic combination in treating hypertension, and poses less risk of diabetes. Other recent studies suggest that beta-blockers may increase the risk of stroke, and should not be a first-line choice for high blood pressure treatment.

Do not abruptly stop taking these drugs. The sudden withdrawal of beta blockers can rapidly increase heart rate and blood pressure. The doctor may want the patient to slowly decrease the dose before stopping completely.
Beta blockers are categorized as non-selective or selective. Non-selective beta blockers such as carvedilol and propranolol may sometimes narrow bronchial airways. These beta blockers should not be used by patients with asthma, emphysema, or chronic bronchitis.
Beta blockers can lower HDL (“good”) cholesterol.
These drugs can hide warning signs of low blood sugar (hypoglycemia) in patients with diabetes. When combined with a diuretic, the risk of diabetes may be increased.

Common Side Effects

Fatigue and lethargy
Vivid dreams and nightmares
Depression
Memory loss
Dizziness and lightheadedness
Reduced ability to exercise
Coldness in extremities (legs, toes, arms, hands)

Check with your doctor about any side effects. Do not stop taking these drugs on your own..

Angiotensin-converting enzyme (ACE) inhibitors open blood vessels and decrease the workload of the heart. They are used to treat high blood pressure but can also help improve heart and lung muscle function.

These drugs are particularly important for patients with diabetes. A large study reported that patients with diabetes who took these drugs had fewer heart attacks and lower overall mortality rates than patients who took other types of high blood pressure medications. ACE inhibitors may also help slow progression of kidney disease, in addition to controlling blood pressure. They may also be better at preventing the development of diabetes in patients with kidney disease than other types of blood pressure medication. In a 2006 study of African-American patients with high blood pressure and kidney disease, patients who took an ACE inhibitor had a lower risk of developing diabetes than those who took a calcium channel blocker or beta-blocker drug.

Brands. ACE inhibitors include captopril (Capoten), enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), ramipril (Altace), perindopril (Aceon), and lisinopril (Prinivil, Zestril).

Common Side Effects of ACE Inhibitors:

Low blood pressure is the main side effect of ACE inhibitors. This can be severe in some patients, especially at the start of therapy.
Irritating cough is a common side effect, which some people find intolerable. Although all ACE inhibitors can have this side effect, sometimes switching to another brand will reduce this symptom.
ACE inhibitors can harm a developing fetus and should not be used during pregnancy. While it has long been known that these drugs can cause problems in the second and third trimester, an important 2006 study indicated that ACE inhibitors can also cause major heart birth defects when taken during the first trimester. The FDA and the American Heart Association recommend that women who become pregnant should change from ACE inhibitors to another type of blood pressure drug as soon as possible. Women of child-bearing age who are considering becoming pregnant should also discuss alternative drugs with their doctors.

Uncommon Side Effects of ACE Inhibitors:

ACE inhibitors protect against kidney disease, but they may also increase potassium retention by the kidneys. If potassium levels become extremely high, they can cause the heart to stop beating (cardiac arrest). This side effect is rare, except in patients with significant kidney disease. Because of this risk, ACE inhibitors are not usually used in combination with potassium-sparing diuretics or potassium supplements.
A rare but severe side effect is granulocytopenia, an extreme reduction in infection-fighting white blood cells.
In very rare cases, patients suffer a sudden and severe allergic reaction, called angioedema that causes swelling in the eyes and mouth and may close off the throat.

Patients who have difficulty tolerating ACE inhibitor side effects are usually switched to an angiotensin-receptor blocker (ARB).

ARBs, also known as angiotensin II receptor antagonists, are similar to ACE inhibitors in their ability to open blood vessels and lower blood pressure. They may have fewer or less-severe side effects than ACE inhibitors, especially coughing, and are sometimes prescribed as an alternative to ACE inhibitors. ARBs are particularly important drugs for patients with diabetes. They may help protect against kidney disease and kidney failure.

A 2006 study in the New England Journal of Medicine suggested that some patients with prehypertension may benefit from treatment with an ARB drug. Patients in the study received candesartan (Atacand).

Brands. Losartan (Cozaar, Hyzaar), olmesartan (Benicar) candesartan (Atacand), telmisartan (Micardis), eprosartan (Teveten), irbesartan (Avapro), and valsartan (Diovan). A combination medication containing candesartan and the diuretic hydrochlorothiazide (Diovan HCT, Atacand HCT) is also available.

Side Effects:

Low blood pressure
Dizziness and lightheadedness
Raised potassium levels
Drowsiness
Nasal congestion
Should not be used during pregnancy

Calcium-channel blockers (CCBs), or calcium antagonists, help relax blood vessels. Along with diuretics, CCBs may work better than other drug classes for lowering blood pressure in African-Americans. Recent research indicates that newer types of drugs (CCBs, ACE inhibitors) may be a better treatment option for some patients than older drugs (especially beta blockers).

Brands. Diltiazem (Cardizem, Dilacor), amlodipine (Norvasc), felodipine (Plendil), isradipine (DynaCirc), verapamil (Calan, Isoptin, Verelan), nisoldipine (Sular), nicardipine (Cardene), nifedipine (Adalat, Procardia), lercanidipine (Zanidip), lacidipine (Motens), and nitrendipine (Nitrepin). In 2004, a dual-therapy calcium channel blocker-statin combination drug (Caduet) was approved to treat high blood pressure and high cholesterol. Caduet is a fixed-dose combination of amlodipine and atorvastatin.

Side Effects:

Swelling in the feet
Constipation
Fatigue
Erectile dysfunction
Gingivitis
Rash
Food interactions (do not take CCBs with grapefruit or Seville orange products)

Alpha blockers such as doxazosin (Cardura), prazosin (Minipress), and terazosin (Hytrin) help widen small blood vessels. They are generally not used as first-line drugs for high blood pressure, but are prescribed if other drugs do not work or as add-on medication.

Vasodilators, which help open blood vessels by relaxing muscles in the blood vessel walls. These drugs are usually used in combination with a diuretic or a beta-blocker. They are rarely used by themselves. Vasodilators include hydralazine (Apresoline), clonidine (Catapres), available in tablets or as a skin patch), and Minoxidil (Loniten). Some of these drugs should be used with caution or not at all in people who have angina or who have had a heart attack.

Aliskiren (Tekturna). In 2007, the FDA approved aliskiren for treatment of high blood pressure. Aliskiren can be taken either alone or in combination with other blood pressure medication. It should not be used during pregnancy as it can cause injury or death to the fetus. Aliskiren is the first hypertension drug that inhibits renin, a kidney enzyme that is associated with the regulation of blood pressure.

Statins. Statins, common drugs used to lower cholesterol, are proving to have many other health benefits. They include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). In an important 2002 study, patients with high blood pressure but normal or slightly high cholesterol levels had fewer heart attacks and strokes when they took the a statin drug. In 2004, a calcium channel blocker-statin combination drug (Caduet) was approved to treat simultaneously high blood pressure and high cholesterol. Caduet is a fixed-dose combination of amlodipine and atorvastatin.

Resources

www.acc.org -- American College of Cardiology
www.americanheart.org -- American Heart Association
www.ash-us.org -- American Society of Hypertension
www.nhlbi.nih.gov/hbp -- National Heart, Lung, and Blood Institute
www.nhlbi.nih.gov/health/public/heart/hbp/dash -- DASH diet
www.ishib.org -- International Society on Hypertension in Blacks
www.eatright.org -- American Dietetic Association

References

Barzilay JI, Davis BR, Cutler JA, Pressel SL, Whelton PK, Basile J, et al. Fasting glucose levels and incident diabetes mellitus in older nondiabetic adults randomized to receive 3 different classes of antihypertensive treatment: a report from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Arch Intern Med. 2006 Nov 13;166(20):2191-201.

Beulens JW, Rimm EB, Ascherio A, Spiegelman D, Hendriks HF, Mukamal KJ. Alcohol consumption and risk for coronary heart disease among men with hypertension. Ann Intern Med. 2007 Jan 2;146(1):10-9.

Cooper WO, Hernandez-Diaz S, Arbogast PG, Dudley JA, Dyer S, Gideon PS, et al. Major congenital malformations after first-trimester exposure to ACE inhibitors. N Engl J Med. 2006 Jun 8;354(23):2443-51.

Davis BR, Piller LB, Cutler JA, Furberg C, Dunn K, Franklin S, et al. Role of diuretics in the prevention of heart failure: the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. Circulation. 2006 May 9;113(18):2201-10.

Djousse L, Pankow JS, Hunt SC, Heiss G, Province MA, Kabagambe EK, et al. Influence of saturated fat and linolenic acid on the association between intake of dairy products and blood pressure. Hypertension. 2006 Aug;48(2):335-41.

Forman JP, Rimm EB, Curhan GC. Frequency of analgesic use and risk of hypertension among men. Arch Intern Med. 2007 Feb 26;167(4):394-9.

Peila R, White LR, Masaki K, Petrovitch H, Launer LJ. Reducing the risk of dementia: efficacy of long-term treatment of hypertension. Stroke. 2006 May;37(5):1165-70.

Taylor EN, Hu FB, Curhan GC. Antihypertensive medications and the risk of incident type 2 diabetes. Diabetes Care. 2006 May;29(5):1065-70.

Thornley-Brown D, Wang X, Wright JT Jr, Randall OS, Miller ER, Lash JP, et al. Differing effects of antihypertensive drugs on the incidence of diabetes mellitus among patients with hypertensive kidney disease. Arch Intern Med. 2006 Apr 10;166(7):797-805.

Review Date:
4/12/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Stroke

FitSugar — Wed, 08 Oct 2008 17:35:08 -0700

In This Report

Highlights
Introduction
Symptoms
Risk Factors
Prognosis
Prevention
Diagnosis
Managing a Stroke
Medications
Surgery
Recovery
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Statin Drug Approved for Stroke Prevention

In 2007, the FDA approved the cholesterol drug atorvastatin (Lipitor) to reduce the risk of stroke in patients with heart disease.
High-dose atorvastatin may help reduce the risk of recurrent stroke in patients who have had a recent stroke or transient ischemic attack, according to a New England Journal of Medicine study.

Drug Warnings

In 2006, the FDA strengthened the warning label for the anticoagulant drug warfarin (Coumadin) to emphasize its bleeding risks. However, warfarin is still the gold standard treatment for most patients with atrial fibrillation.
Evidence suggests that people at risk for stroke should avoid taking non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil) and diclofenac (Cataflam). COX-2 inhibitors should only be used as a last resort for pain relief. Try non-drug treatments (physical therapy, hot/cold compresses) first.

Aspirin

In 2007, the American Heart Association (AHA) issued new heart disease prevention guidelines for women. The AHA recommends low-dose aspirin therapy for women over age 65 who are at risk for stroke.
The combination of aspirin and dipyridamole (Aggrenox) may be better than aspirin alone in preventing major stroke in patients who have had a minor stroke, suggests a Lancet study.

Diagnosis

Magnetic resonance imaging (MRI) is better than computed tomography (CT) in detecting whether stroke (especially ischemic stroke) has occurred, indicates an important Lancet study.

Surgery

Carotid endarterectomy appears to be superior to and safer than carotid angioplasty and stenting (CAS) for most patients with artery stenosis (narrowing) of over 60%, suggest several recent studies. Most experts recommend CAS only for patients who have severe stenosis (greater than 70%) and high surgical risk.

Rehabilitation

Constraint-induced movement therapy (CIMT) may help patients who have recently had a stroke regain use of a paralyzed arm. The technique involves repetitive motion exercises while restraining the less functional arm.

Introduction

Blood Flow Blockage. The brain receives about 25% of the body's oxygen, but it cannot store it. Brain cells require a constant supply of oxygen to stay healthy and function properly. Therefore, blood needs to be supplied continuously to the brain through two main arterial systems:

The carotid arteries come up through either side of the front of the neck. (To feel the pulse of a carotid artery, place your fingertips gently against either side of your neck, right under the jaw.)
The basilar artery forms at the base of the skull from the vertebral arteries, which run up along the spine, join, and come up through the rear of the neck.

The Circle of Willis is the joining area of several arteries at the bottom (inferior) side of the brain. At the Circle of Willis, the internal carotid arteries branch into smaller arteries that supply oxygenated blood to over 80% of the cerebrum.

A reduction of, or disruption in, blood flow to the brain is the primary cause of a stroke. Blockage for even a short period of time can be disastrous and cause brain damage or even death.

Click the icon to see an image of the brain.

A stroke is usually defined as two types:

Ischemic (caused by a blockage in an artery)
Hemorrhagic (caused by a tear in the artery's wall that produces bleeding in the brain)

The consequences of a stroke, the type of functions affected, and the severity, depend on where in the brain it has occurred and the extent of the damage.

Ischemic strokes are by far the more common type, causing over 80% of all strokes. Ischemia means the deficiency of oxygen in vital tissues. Ischemic strokes are caused by blood clots that are usually one of three types:

Thrombotic stroke
Embolic stroke
Lacunar stroke

Thrombotic or Large-Artery Stroke and Atherosclerosis. The thrombotic stroke accounts for about 60% of all strokes. It usually occurs when an artery to the brain is blocked by a thrombus (blood clot) that forms as the result of atherosclerosis (commonly known as hardening of the arteries). These strokes are also sometimes referred to as large-artery strokes. The process leading to thrombotic stroke is complex and occurs over time:

The arterial walls slowly thicken, harden, and narrow until blood flow is reduced, a condition known as stenosis.
These now abnormal arteries become vulnerable to injury. Such injuries signal the immune system to release white blood cells (particularly those called neutrophils and macrophages) at the site. This process is the first step in the inflammatory response, which may play a significant role in the stroke.
Macrophages literally "eat" foreign debris and become foamy cells that attach to smooth muscle cells of blood vessels, causing them to build up.
The immune system, sensing further harm, releases other factors called cytokines, which attract more white blood cells and perpetuate the whole cycle.

As these processes continue, blood flow slows. In addition, other events contribute to the coming stroke:

The injured inner walls fail to produce enough nitric oxide, a substance critical for maintaining blood vessel elasticity. The arteries become calcified and lose elasticity.
The arteries, now hardened and rigid, become susceptible to tearing. In this event, the thrombus (blood clot) forms.
The blood clot then blocks the already narrowed artery and shuts off oxygen to part of the brain. A stroke occurs.

Embolic Strokes and Atrial Fibrillation. An embolic stroke is usually caused by a dislodged blood clot that has traveled through the blood vessels (an embolus) until it becomes wedged in an artery. Embolic strokes account for about 25% of all strokes and may be due to various conditions:

In about 15% of embolic strokes, the blood clots originally form as a result of a rhythm disorder known as atrial fibrillation. This abnormal rhythm is a rapid quivering beat in the upper chambers of the heart (the atria). Because of the irregular pumping, some blood may remain in the heart chamber where it forms clots, which can then break off and travel to the brain as emboli.
Emboli can originate from blood clots that form at the site of artificial heart valves or as a result of heart valve disorders.
Emboli can also occur after a heart attack or in association with heart failure.
Rarely, emboli are formed from fat particles, tumor cells, or air bubbles that travel through the bloodstream.

Lacunar Strokes. Lacunar infarcts are a series of very tiny, ischemic strokes, which cause clumsiness, weakness, and emotional variability. They are actually a subtype of thrombotic stroke and constitute about 38% of this major group. In some populations, such as among Japanese, they are the most common stroke subtypes. They can also sometimes serve as warning signs for a major stroke.

Silent Brain Infarctions. Many elderly people have silent brain infarctions, small strokes that cause no apparent symptoms. They are detected in between 10 - 38% of elderly patients who undergo imaging tests for problems other than stroke. A 2002 study suggested that they double the risk for future stroke. They also may be major contributors to mental impairment in the elderly. Smokers and people with hypertension are at particular risk.

Transient ischemic attacks (TIAs) are mini-ischemic strokes, usually caused by tiny emboli (clots often formed of pieces of calcium and fatty plaque) that lodge in an artery to the brain. They typically break up quickly and dissolve but they do temporarily block the supply of blood to the brain. The mental or physical disturbances resulting from TIAs generally clear up in less than a day, with nearly all symptoms resolving in less than an hour.

However, experts now advise that a TIA should be taken very seriously and treated as aggressively as a stroke. Both stroke and TIA increase the risk for a subsequent stroke. Moreover, the risk for having another stroke can be as high as 40% within 5 years. The American Heart Association/American Stroke Association recommends these guidelines to prevent a second stroke after TIA:

Lifestyle changes.

Stop smoking
Limit alcohol
Increase exercise (30 minutes a day of moderate physical activity)
Lose excess weight (waist measurements should be no more than 35 inches for women and 40 inches for men; body mass index should be 18.5 - 24.9)

Drug treatments.

Drugs to control cholesterol, high blood pressure, and (for people with diabetes) high blood sugar levels
Antiplatelet therapy such aspirin, dipyridamole, or clopidogrel)

Surgery.

Carotid endarterectomy surgery or carotid artery stenting is recommended for patients with severe (70% or more) carotid stenosis (narrowing or blockage of one or both arteries in the neck)
Endarterectomy or stenting may also be appropriate for some patients with moderate stenosis (50 - 69%)
Endarterectomy and stents are not needed for patients with mild stenosis (less than 50%)

Over 15% of strokes occur from hemorrhage (sudden bleeding) in the brain. In a healthy brain, brain cells called neurons are protected from exposure to blood by the blood-brain barrier, a wall of tiny vessels and structural cells. In a hemorrhagic stroke, however, this barrier is broken.

Hemorrhagic strokes may be categorized by how and where they occur.

Parenchymal, or cerebral, hemorrhage strokes. These strokes occur within the brain and account for about 10% of all strokes. They are most often the result of hypertension exerting excessive pressure on arterial walls already damaged by atherosclerosis. Heart attack patients who have been given drugs to break up blood clots or blood-thinning drugs have a slightly elevated risk of this type of stroke.
Subarachnoid hemorrhagic strokes. This other major hemorrhagic stroke accounts for about 5% of all strokes. This kind of stroke occurs when a blood vessel on the surface of the brain bursts, leakign blood into the subarachnoid space, an area between the brain and the skull. They are usually caused by the rupture of an aneurysm, a weakening in the blood vessel wall, which is often an inherited trait.
Arteriovenous malformation (AVM) is an abnormal connection between arteries and veins. If it occurs in the brain and ruptures, it can also cause a hemorrhagic stroke.

Symptoms

People at risk and partners or caretakers of people at risk for stroke should be aware of the general symptoms. The stroke victim should get to the hospital as soon as possible after these warning signs appear. It is particularly important for people with migraines or frequent severe headaches to understand how to distinguish between their usual headaches and symptoms of stroke.

The American Stroke Association lists the following five warning signs of stroke. PEOPLE SHOULD IMMEDIATELY CALL FOR EMERGENCY ASSISTANCE IF THEY EXPERIENCE ANY OF THESE SYMPTOMS:

Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
Sudden confusion, trouble speaking or understanding
Sudden trouble seeing in one or both eyes
Sudden trouble walking, dizziness, loss of balance or coordination
Sudden, severe headache with no known cause

Research indicates that patients receive faster treatment for stroke if they arrive by ambulance rather than coming to the emergency room on their own.

An easy way to remember the signs of stroke, and what to do, is by the acronym "F.A.S.T." If you think you or someone else is having a stroke, the National Stroke Association's F.A.S.T. test advises:

(F)ACE. Ask the person to smile. Check to see if one side of the face droops.
(A)RMS. Ask the person to raise both arms. See if one arm drifts downward.
(S)PEECH. Ask the person to repeat a simple sentence. Check to see if words are slurred and if the sentence is repeated correctly.
(T)IME. If a person shows any of these symptoms, time is essential. It is important to get to the hospital as quickly as possible. Call 9-1-1. Act FAST.

The symptoms of a transient ischemic attack (TIA) and early ischemic stroke are similar. In the case of a TIA, however, the symptoms should resolve within 24 hours. Symptoms depend on where the injury in the brain occurs. The origin of the stroke is usually either the carotid or basilar arteries.

Symptoms From Blockage in the Carotid Arteries. The carotid arteries stem off of the aorta (the primary artery leading from the heart) and lead up through the neck around the windpipe and on into the brain. When TIAs or stroke occur from blockage in the carotid artery, which they often do, symptoms may occur in either the retina of the eye or the cerebral hemisphere (the large top part of the brain).

Symptoms include the following:

When oxygen to the eye is reduced, people describe the visual effect as a shade being pulled down. People may develop poor night vision. About 35% of TIAs are associated with temporary lost vision in one eye. Although such events are risk factors for future stroke, they pose a lower risk for a stroke and its complications than more widespread TIA symptoms.
When the cerebral hemisphere is affected, a person can experience problems with speech and partial and temporary paralysis, drooping eyelid, tingling, and numbness, usually on one side of the body. The stroke victim may be unable to express thoughts verbally or to understand spoken words. If the stroke injuries are on the right side of the brain, the symptoms will develop on the left side of the body and vice versa.
Uncommonly, patients may experience seizures.

Symptoms From Blockage in the Basilar Artery. The other major site of trouble, the basilar artery, is formed at the base of the skull from the vertebral arteries, which run up along the spine and join at the back of the head. When stroke or TIAs occur here, both hemispheres of the brain may be affected so that symptoms occur on both sides of the body. The following symptoms may develop:

Temporarily dim, gray, blurry, or lost vision
Tingling or numbness in the mouth, cheeks, or gums
Headache, usually in the back of the head
Dizziness
Nausea and vomiting
Difficulty swallowing
Weakness in the arms and legs, sometimes causing a sudden fall

Such strokes usually occur in the brain stem, which can have profound affects on breathing, blood pressure, heart rate, and other vital functions, but does not affect thinking or language.

Speed of Symptom Onset. The speed of symptom onset of a major ischemic stroke may indicate its source:

If the stroke is caused by a large embolus (a clot that has traveled to an artery in the brain), the onset is sudden. Headache and seizures can occur within seconds of the blockage.
When thrombosis (a blood clot that has formed within the brain) causes the stroke, the onset usually occurs more gradually, over minutes to hours. On rare occasions it progresses over days to weeks.

Click the icon to see an image of carotid dissection.

Click the icon to see an image of stroke.

Cerebral Hemorrhage Symptoms. Symptoms of a cerebral, or parenchymal, hemorrhage typically begin very suddenly and evolve over several hours and include:

Headache
Nausea and vomiting
Altered mental states
Seizures

Subarachnoid Hemorrhage. When the hemorrhage is a subarachnoid type, warning signs may occur from the leaky blood vessel a few days to a month before the aneurysm fully develops and ruptures. Warning signs may include:

Abrupt headaches
Nausea and vomiting
Sensitivity to light
Various neurologic abnormalities. Seizures, for example, occur in about 8% of patients.

When the aneurysm ruptures, the stroke victim may experience:

A terrible headache
Neck stiffness
Vomiting
Altered states of consciousness
Eyes may become fixed in one direction or lose vision
Stupor, rigidity, and coma

Risk Factors

New or recurrent strokes affect about 700,000 Americans every year. Although incidence of stroke has increased, more people are surviving stroke, and the death rate is declining. While age is the major risk factor, people with stroke are likely to have more than one risk factor.

Older Adults. People most at risk for stroke are older adults, particularly those with high blood pressure, who are sedentary, overweight, smoke, or have diabetes. Older age is also linked with higher rates of post-stroke dementia.

Younger Adults. Younger people are not immune, however. About 28% of stroke victims are under age 65.

In most age groups except older adults, stroke is more common in men than in women. However, it kills more women than men, regardless of ethnic groups. It is not clear why women have a higher mortality rate from stroke. The arteries that lead to the brain may be more vulnerable to the effects of plaque build-up in women than in men.

In 2007, the American Heart Association released new heart disease prevention guidelines for women. The new guidelines recommend daily aspirin therapy (75 - 325 mg/day) to help prevent stroke in high-risk women over the age of 65. For older women with a lower stroke risk, the AHA recommends 81 mg of aspirin a day or 100 mg of aspirin every other day. Aspirin does not appear to provide much stroke protection benefit for women under the age of 65.

All minority groups, including Native Americans, Hispanics, and African-Americans, face a significantly higher risk for stroke and stroke death than Caucasians. The risk is also higher in Asian Americans, although stroke rates appear to be declining in this group. The differences in risk among all groups diminish as people age.

The greatest disparity in risk occurs in young adults. Younger African-Americans are two to three times more likely to experience a stroke than their Caucasian peers and four times more likely to die from one. They also face a higher risk for death from heart disease. African-Americans have a higher prevalence of diabetes and hypertension than other groups. However, studies suggest that socioeconomic factors also affect these differences.

People in the southeastern U.S. have had the highest risk for stroke in the country for some years; those at particular risk live in North Carolina, South Carolina, and Georgia. This risk may be shifting westward. High stroke rates are also occurring in the lower Mississippi valley and in Southern California. Socioeconomic differences do not fully explain these higher-risk areas.

Heart disease and stroke are closely tied for many reasons:

Patients with one condition often have risk factors for the other, such as high blood pressure, atherosclerosis (hardening of the arteries), and diabetes.
The risk of stroke increases during surgical procedures involving the coronary arteries, including coronary bypass operations and angioplasty. Coronary bypass poses the greater risk -- about 2 - 5%.
Anti-clotting drugs used for treatment of heart disease and heart attacks slightly increase the risk for hemorrhagic stroke.
A heart attack itself poses a high risk for stroke, which, according to a major 2002 study, is 2.5% in the first 6 months and 5% per year thereafter. In the study, patients with a higher risk (about 4%) for stroke within 6 months of a heart attack tended to be older (over age 75), African-American, or to have a history of a previous stroke, atrial fibrillation, hypertension, diabetes, or peripheral artery disease. Most people at high risk have more than one of these problems.

High Blood Pressure (Hypertension). High blood pressure (known medically as hypertension ) contributes to 70% of all strokes. Researchers have estimated that controlling blood pressure can prevent nearly 40% of strokes.

Two numbers are used to describe blood pressure phases and may affect stroke risk separately:

The systolic pressure (the higher and first number) is measured as the heart contracts to pump out the blood. Evidence suggests that elevated systolic pressure poses a significant danger for heart and stroke emergencies when diastolic is normal, a condition called isolated systolic hypertension. The wider the spread between the systolic and diastolic measurements, the greater the danger.
The diastolic pressure (the lower and second number) is measured as the heart relaxes to allow blood to refill the heart between beats. Abnormally higher diastolic pressure is a strong predictor of heart attack and stroke in most people with hypertension.
Stroke from Low Blood Pressure (Hypotension). Uncommonly, blood pressure that is too low can reduce oxygen supply to the brain and cause a stroke. This can occur from a heart attack, a major bleeding episode, an overwhelming infection, or rarely, from surgical anesthesia or from over-treatment of high blood pressure.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated, and controlled by medication, lifestyle changes, or a combination of both.

Click the icon to see an image of the risks of untreated hypertension.

Atrial Fibrillation. About one in six strokes are due to atrial fibrillation. This is a heart rhythm disorder in which the atria (the upper chambers in the heart) beat very quickly and nonrhythmically. The blood pools instead of being pumped out, increasing the risk for formation of blood clots that break loose and travel toward the brain. Atrial fibrillation poses a six-fold increased risk for stroke and may also pose a higher risk for complications after a stroke.

Atrial fibrillation is uncommon in people under 60 years old, but about 6% of adults over age 80 have this heart rhythm disorder. In this patient group, the risk for stroke may be higher or lower with the presence of other risk factors, including having heart failure, high blood pressure, diabetes, and a previous history of stroke, TIA, or rheumatic heart disease. More women than men have AF, but risk for stroke is higher in women with this condition than in men.

Patent Foramen Ovale. Patent foramen ovale (PFO) is a flap-like opening between chambers of the heart. The foramen ovale is always open during fetal development to enhance blood flow to the fetus. It then typically closes after birth when the lungs take over. However, evidence suggests that it remains open in up to 30% of adults. In such cases, blood moves backward (right to left) through this opening when pressure in the right chamber exceeds the left. Large PFOs are a major cause of stroke, particularly in younger adults. Treatments include anti-clotting drugs and procedures for closing the opening.

Atrial Septal Aneurysm. Atrial septal aneurysm is an inborn condition in which part of the atrium (one of the heart chambers) bulges out. Studies indicate that this may pose a slight risk for stroke in young people.

People who smoke a pack a day have almost two and a half times the risk for stroke as nonsmokers. Smoking increases both hemorrhagic and ischemic stroke risk. The risk for stroke may remain elevated for as long as 14 years after quitting, so the earlier one quits the better.

Heart disease and stroke are the leading causes of death in people with diabetes. Diabetes is a strong risk factor for ischemic stroke, perhaps because of accompanying risk factors, such as obesity and high blood pressure. Diabetes does not appear to increase the risk for hemorrhagic stroke. Diabetes is second only to high blood pressure as the main risk factor for stroke. The risk is highest for adults newly diagnosed with type 2 diabetes and patients with diabetes who are younger than age 55. African-Americans with diabetes are at even higher risk for stroke at a younger age.

Studies have also implicated insulin resistance, an important disease mechanism in type 2 diabetes, as an independent factor in the development of atherosclerosis and stroke. With this condition, insulin levels are normal to high, but the body is unable to use the insulin normally to metabolize blood sugar. The body compensates by raising the level of insulin, which in turn increases the risk for blood clots and reduces HDL levels (the beneficial form of cholesterol). Some studies have also reported a worse outcome in patients whose blood sugar levels are high at the time of a stroke.

Obesity may increase the risk for both ischemic and hemorrhagic stroke independently of other risk factors that often co-exist with excess weight, including insulin resistance and diabetes, high blood pressure, and unhealthy cholesterol level. Weight that is centered around the abdomen (the so-called apple shape) has a particularly high association with stroke, as it does for heart disease, in comparison to weight distributed around hips (pear-shape).

Obesity is particularly hazardous when it is one of the components of metabolic syndrome. This syndrome is diagnosed when three of the following conditions are present: abdominal obesity, low HDL cholesterol, high triglyceride levels, high blood pressure, and insulin resistance. Because metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease, people with this syndrome are at increased risk for stroke even before diabetes develops.

Although an unhealthy balance of cholesterol and other lipids (fatty compounds) plays a major role in heart disease, its role in stroke is less clear. Different lipids may have different effects:

Ischemic Stroke. The effects of high total cholesterol and LDL levels on stroke are not clear. One study suggested that the risk for ischemic stroke increases when total cholesterol is above 280 mg/dL. HDL (the so-called good cholesterol) may protect against ischemic stroke (although statins have little effect on HDL).

Hemorrhagic Stroke. HDL may reduce the risk for hemorrhagic stroke (bleeding in the brain). People with overall cholesterol levels below 180 mg/dL, however, may be at risk for hemorrhagic stroke, particularly if they also have high blood pressure. This is a far less common stroke, however, than ischemic stroke.

In any case, reducing cholesterol is extremely important in anyone with heart disease and abnormal lipid levels.

Genetics may be responsible for many of the causes of stroke. Studies indicate that a family history of stroke, particularly in one's father, is a strong risk factor for stroke.

Genetics and Subarachnoid Hemorrhage. Genetic factors account for between 7 - 20% of cases of subarachnoid hemorrhage. Ruptured aneurysms that occur in such patients tend to happen at an earlier age, are usually smaller, and are more apt to recur than in those without an inherited condition. A study of people who had suffered subarachnoid hemorrhages found that first-degree relatives of these stroke victims had a high lifetime risk of between 2 - 5%. Some experts recommend screening for aneurysms in people with more than one close relative who suffered a hemorrhagic stroke.

Inherited Disorders that Contribute to Stroke. Some cases of atrial fibrillation may be inherited. Genetic disorders that cause connective tissue disorders are also associated with stroke from hemorrhage; they include polycystic kidney disease, Ehlers-Danlos syndrome type IV, neurofibromatosis type 1, Marfan's syndrome, and moyamoya disease.

Specific Genetic Factors Under Investigation. Specific genetic factors are under investigation. They include:

Inherited deficiencies in protein factors C and S, which inhibit blood clotting, may be responsible for certain cases of stroke in young adults.
A genetic mutation in a factor V Leiden may be related to blood clotting risks.
People who have inherited a gene called apolipoprotein (Apo) E-4 may be at increased risk of stroke. This gene is also associated with Alzheimer's disease.

Stress. One survey revealed that men who had a more intense response to stressful situations, such as waiting in line or problems at work, were more likely to have strokes than those who did not report such distress. In some people, prolonged or frequent mental stress causes an exaggerated increase in blood pressure, which in turn can increase the risk for stroke.

Depression. Depression has also been linked to higher risk for stroke and lower stroke survival rates. In one study, patients with severe depression had a 73% higher risk for stroke, and those with moderate depression had a 25% higher risk than average. The risk for stroke in African-Americans with depression was 160% higher than average.

Studies indicate that migraine or severe headache may be a risk factor for stroke in both men and women, especially before age 50. Overall, between 2 - 3% of ischemic strokes occur in people with a history of migraine. However, in patients under age 45, about 15% of all strokes (and 30 - 60% of strokes in young women) are associated with a history of migraines, particularly migraine with aura. Some evidence suggests that some strokes in these cases may be due to excessive activation of the nervous system and the dehydration from vomiting that occurs during a severe migraine with aura.

The actual risk itself for migraineurs is low, however. In one study, women with migraines had a 2.7% risk of stroke, with the greatest risk between the ages of 45 - 65. Studies suggest specific risk factors for younger women with migraines, particularly those with auras, include taking high-estrogen oral contraceptives (OCs). (Whether progesterone-alone contraceptives carry any risk is unknown.) In migraineurs who take OCs, the risk increases with high blood pressure, smoking, or both.

Inflammation that occurs with various infections has been associated with stroke. One study found that patients hospitalized for stroke were three times more likely than patients without strokes to have recently been exposed to infections, usually mild ones in the respiratory tract.

Varicella Virus. Varicella zoster virus (the virus that causes chicken pox and shingles) has been associated with cerebral vasculitis, a condition in which blood vessels in the brain become inflamed. It is a very rare cause of stroke in children. The virus has also been associated with some cases of stroke in young adults.

Chlamydia Pneumonia. Some investigators suspect that some infections may produce inflammation in the arteries that can lead to stroke over time. (Similar work is underway in heart disease.) Researchers are particularly interested in Chlamydia pneumoniae, a non-bacterial organism that causes mild pneumonia in adults. Chronic infection has been linked with a higher risk for stroke, and evidence of the organism has been observed in thickened inner vessel walls of the carotid arteries in some studies. Chlamydia has also been linked to heart disease.

Periodontal Disease. A number of studies now strongly support an association between periodontal disease and cardiovascular disorders. According to a major analysis, periodontal (gum) disease is associated with a 20% higher risk for ischemic stroke and heart disease. The added risk may be even greater in adults under 65. Recent evidence points to the inflammatory response as the common element.

In 2007, the American Heart Association (AHA) issued a scientific statement encouraging doctors to change the way they prescribe pain relief medication for patients at risk for heart disease or stroke. The AHA recommends that at-risk patients first try non-drug methods of pain relief (physical therapy, exercise, weight loss to reduce stress on joints, and heat or cold therapy). If these methods don’t work, patients should take the lowest possible dose of acetaminophen (Tylenol) or aspirin. COX-2 inhibitors, such as celecoxib (Celebrex), should be the last resort.

In 2005, the FDA warned that all NSAIDs -- with the exception of aspirin -- carry heart risks. In particular, the NSAIDs ibuprofen (Advil, Motrin) and diclofenac (Cataflam, Voltaren) appear to carry increased risks for heart attack and stroke.

A number of medical or physical conditions may contribute to the risk for stroke:

Sleep apnea. This common disorder, in which the throat becomes obstructed during sleep, may contribute to the narrowing of the carotid artery, appearing to increase the risk for stroke three- to six-fold.
Pregnancy. Pregnancy carries a very small risk for stroke, mostly in women with pregnancy related high blood pressure and in those with cesarean delivery. The risk appears to be higher in the postpartum (post-delivery) period, perhaps because of the sudden change in circulation and hormone levels.
Anti-phospholipid antibodies. Nearly 40% of young people with strokes and 10% of all stroke patients have components of the immune system known as anti-phospholipid antibodies that increase the chance for blood clots.
Sickle-cell anemia. People with sickle-cell anemia are at risk for stroke at a young age.
Drug abuse, particularly with cocaine and, increasingly, methamphetamine, is a major factor in the incidence of stroke in young adults. Anabolic steroids, used for body-building and sports enhancement, also increase risk.

Timing. Like heart attack and sudden cardiac death, stroke appears to be more common in the morning hours, perhaps due to a temporary rise in blood pressure at that time. Various studies point to a higher risk for stroke on weekends, Mondays, and holidays. The risk for hemorrhagic stroke may also be higher in the winter, particularly in older people with high blood pressure.

Homocysteine and Vitamin B Deficiencies. Abnormally high blood levels of the amino acid homocysteine, which occur with deficiencies of vitamin B6, B12, and folic acid, may be linked to an increased risk of coronary artery disease and stroke.

Neck Manipulation. Some studies have reported a higher risk for stroke from injury to the carotid artery after neck manipulation by a chiropractor.

Prognosis

A stroke, the third leading cause of death in the U.S., is always serious. In 2004, over 150,000 Americans died of stroke with women accounting for 61% of these stroke deaths. The mortality rates are declining, however. Over 75% of patients survive a first stroke during the first year, and over half survive beyond 5 years.

People who suffer ischemic strokes have a much better chance for survival than those who experience hemorrhagic strokes. Among the ischemic stroke categories, the greatest dangers are posed by embolic strokes, followed by thrombotic and lacunar strokes. Hemorrhagic stroke not only destroys brain cells but also poses other complications, including increased pressure on the brain or spasms in the blood vessels, both of which can be very dangerous. Studies suggest, however, that survivors of hemorrhagic stroke have a greater chance for recovering function than those who suffer ischemic stroke.

Between 50 - 70% of people recover functional independence after a stroke. However, between 15 - 30% of those who survive either an ischemic or hemorrhage stroke suffer some permanent disability. On the encouraging side, one study reported that people who survived for many years after a stroke had a chance for independent living that was about the same as for their peers who had not suffered strokes. The stroke patients even appeared to be less depressed than the comparison group.

The National Institutes of Health (NIH) have devised a scoring system that helps predict the severity and outcome of the stroke by scoring 11 factors (levels of consciousness, gaze, visual fields, facial movement, motor functions in the arm and leg, coordination, sensory loss, problems with language, inability to articulate, and attention). Up to 70% of patients with ischemic strokes who score less than 10 have a favorable outlook after a year, while only 4 - 16% of patients do well if their score is more than 20.

The risk for recurring stroke is highest within the first few weeks and months. The risk is about 14% in the first year and about 5% thereafter, so preventive measures should be instituted as soon as possible. Some specific risk factors for early recurrence include:

Older age
Evidence of blocked arteries (a history of coronary artery disease, peripheral artery disease, ischemic stroke, or TIA)
Hemorrhagic or embolic stroke
Diabetes
Alcoholism
Valvular heart disease
Atrial fibrillation

Prevention

Forty percent of patients who have had a stroke or TIA will suffer a subsequent stroke within 5 years. In 2006, the American Heart Association/American Stroke Association released guidelines for preventing a second stroke. These guidelines recommend:

Quit Smoking. Also avoid exposure to second-hand smoke.

Maintain Weight. People should aim for a BMI index of 18.5 - 24.9. In people who are obese, reducing weight to this level can reduce the risk for stroke by 15% in men and 22% in women. Waist measurements should be no more than 35 inches for women and 40 inches for men.

Exercise. Everyone in normal health should engage in at least moderate physical activity for a minimum of 30 minutes on most -- if not all -- days of the week.

Limit alcohol. No more than 2 drinks a day for men and 1 drink a day for nonpregnant women.

Healthy Diet. Everyone should aim for a diet that contains a healthy balance of fruits, vegetables, grains, fish, nuts, legumes, poultry, lean meat, and low-fat dairy items. Avoid saturated fats and trans fatty acids.

Improve Cholesterol. People with at least two risk factors and a 10-year risk for heart disease or stroke of more than 20% should aim for LDL levels of less than 100 mg/dl. Raising HDL levels is important for people at risk for stroke. Statins are now used in most cases.

Keep Blood Pressure Low. People in normal health should aim for 139/89 mm Hg or less. Patients with certain health problems, such as diabetes, should aim lower.

Control Diabetes. People with diabetes should aim for fasting blood glucose levels of less than 110 mg/dl and hemoglobin A1C of less than 7%. Blood pressure goals should be 130/80 mm Hg or less.

Take Aspirin or Other Antiplatelet Therapy. People at high risk for heart disease should take a low-dose aspirin every day, unless they have medical reasons to avoid aspirin. (As an alternative to aspirin alone, your doctor may prescribe clopidogrel alone or aspirin plus extended release dipyridamole.) Aspirin may help to prevent strokes caused by blockage in the artery (ischemic stroke), but it may slightly increase the risk of strokes caused by bleeding in the brain (hemorrhagic stroke). The American Heart Association recommends aspirin therapy for women over age 65 who are at risk for stroke.

Control Atrial Fibrillation. People with atrial fibrillation should use anticoagulants to reduce their risk of blood clots. Carotid Endarterectomy Surgery or Stenting: Recommended for most symptomatic patients with neck artery stenosis (narrowing or blockage) of more than 70% and some patients with stenosis of 50 - 69%.

A healthy diet rich in fruits and vegetables and low in salt and saturated fats may significantly lower the risk for both ischemic and hemorrhagic stroke. For diet plans, the Mediterranean diet may be a particularly good choice for reducing the risk of stroke. [See In-Depth Report #43: Heart-healthy diet.]

Fruits and Vegetables. Studies suggest that people can protect their heart and circulation by eating plenty of fruits and vegetables. Eating at least five servings a day reduces blood pressure and protects against both heart attack and stroke. Important foods include most fruits (especially potassium-rich fruits including bananas, oranges, prunes, and cantaloupes) and vegetables (especially carrots, spinach, celery, alfalfa, mushrooms, lima beans, potatoes, avocados, broccoli). Vegetables, such as broccoli and kale, may be specifically protective against a first ischemic and possibly hemorrhagic stroke. Foods such as apples and tea, which are high in food chemicals called flavonoids, may also be very beneficial.

Whole Grains and Nuts. A 2000 study reported a lower incidence in stroke in women who had a high intake of whole-grain foods. Nuts may also be protective.

Calcium, Potassium, and Magnesium. Calcium, magnesium, and potassium serve as electrolytes in the body. They are important in controlling blood pressure and may also have protective effects against stroke:

Some evidence suggests that diets rich in potassium may protect against stroke by 22 - 40%, mostly by reducing blood pressure but also possibly because of other mechanisms. Low potassium levels may increase the risk for stroke in certain people.

A major study reported that calcium intake is associated with a lower risk for stroke in women, which supports an earlier study reporting a lower risk for stroke in men who drank more milk.

Magnesium deficiencies may increase the risk for atrial fibrillation. No evidence yet exists, however, that taking magnesium supplements is protective.

Salt Restriction. Although the effects of salt restriction are not entirely clear, a 2002 study indicated that even a modest reduction in salt intake for more than a month might reduce the risk of death from stroke by 14% in people with high blood pressure and 6% in people with normal blood pressure.

Fats and Oils. The effects of fats and oils on stroke are complex. One study indicated that middle-aged men without heart disease who had the highest intake of monounsaturated or saturated fat (but not polyunsaturated oils) also had the lowest risk for stroke. Monounsaturated oils, obtained in olive and canola oils, may have protective benefits against both heart disease and stroke. Saturated fats, found in animal products, are known risk factors for heart disease. Some studies suggest, however, that low intake of animal protein and saturated fat increases the risk of hemorrhagic stroke.

Other fat compounds that may be stroke protective are omega-3 fatty acids:

Alpha-linolenic acid is found in canola oil, soybeans, and walnuts. One particular benefit against stroke is its ability to help prevent the formation of blood clots.
Omega-3 fatty acids are categorized as docosahexaenoic (DHA) or eicosapentaneoic acids (EPA). They are found in oily fish and nutritional supplements. These compounds have anti-inflammatory and anti-blood clotting effects and may be significantly beneficial to the heart and reduce the risk for stroke. However, people who have implantable defibrillators should not take fish oil supplements because they may worsen heart rhythm problems.

In any case, consuming fish two or three times a week helps the heart.

Folic Acid and B Vitamins. Deficiencies in the B vitamins folate (known also as folic acid), B6, and B12 have been associated with a higher risk for heart disease in some studies. Such deficiencies produce higher blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. Researchers have been studying whether vitamin B supplements can reduce homocysteine levels and, consequently, heart disease risks.

Several major 2006 studies indicated that while B vitamin supplements help lower homocysteine levels, they have no effect on heart disease outcomes. The studies, published in the New England Journal of Medicine, examined patients who had either recently had a heart attack or suffered from diabetes or heart disease. Results showed a similar number of heart attacks and strokes among patients who took folic acid and B6 and B12 vitamins and those who received placebo. And, the vitamins seemed to increase risks for patients who had undergone stenting. Some experts think that homocysteine may be a marker for heart disease rather than a cause of it.

Antioxidant Vitamins. The effects of antioxidant vitamins and carotenoids on stroke have been studied extensively. Most studies have found that these vitamins do not help protect against stroke. An important 2001 study reported no protection from stroke with vitamins A or E or beta carotene. A 2005 study in the Journal of the American Medical Association found that vitamin E definitely does not protect women from stroke or heart attack.

Smoking. Everyone should quit smoking.

Alcohol. Mild-to-moderate alcohol use (one to seven drinks a week) is associated with a significantly lower risk for ischemic stroke, although not hemorrhagic stroke. Heavy alcohol use, particularly a recent history of drinking, is associated with a higher risk of both ischemic and hemorrhagic stroke.

Coffee. In healthy people with normal blood pressure, drinking a couple of cups of coffee a day is unlikely to do any harm. Caffeine may actually have nerve-protecting properties that may help stroke survivors. Caffeine drinkers, however, might do better to choose tea, which may have beneficial nutrients, and people with existing hypertension should avoid caffeine altogether (since caffeine may increase the risk for stroke in this group).

Exercise helps reduce the risk of atherosclerosis, which can help reduce the risk of stroke. Experts recommend at least 30 minutes of exercise on most, if not all, days of the week.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated, and controlled by medication, lifestyle changes, or a combination of both.

Reducing blood pressure is essential in stroke prevention. Lifestyle measures such as exercise, weight loss, and healthy diets are important for everyone. Drug therapy is recommended for people with hypertension who cannot control their blood pressure through lifestyle changes. Many different types of drugs are used to control blood pressure. They include ACE inhibitors, angiotensin-receptor blockers, beta-blockers, calcium channel blockers, and diuretics. Some drugs, such as Hyzaar, combine an angiotensin receptor blocker with a diuretic to both treat high blood pressure and prevent stroke. [See In-Depth Report #14: High blood pressure.]

Statins have become the most important LDL-lowering drugs. Brands include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). Research increasingly suggests that lowering LDL levels as much as possible is critical for preventing stroke and other heart disease problems. A major analysis of over 200 studies found that statins reduced the risk for heart problems by 60% and stroke by 17%. Another study of over 20,000 people with cerebrovascular disease found that patients who took statin therapy for 2 years reduced their risk of ischemic stroke by 25%.

Statins are proven to reduce the risk of stroke in people at increased risk for heart disease. Research suggests that they may also prevent stroke in patients without heart disease. However, current guidelines recommend that statins should be prescribed to patients without heart disease and with normal LDL levels only if diabetes and several heart disease risk factors are also present.

Researchers are also investigating whether statins might be beneficial in preventing a second stroke in patients who have suffered a stroke or transient ischemic attack (TIA). A study published in 2006 in the New England Journal of Medicine indicated that high-dose atorvastatin (Lipitor) therapy may help reduce the risk of stroke recurrence and other heart events for patients who have had a prior stroke or TIA. In 2006, the FDA expanded atorvastatin’s indications to include reducing the risk of fatal and non-fatal strokes in patients with heart disease

[See In-Depth Report #23: Cholesterol.]

Influenza vaccinations may protect patients with a history of heart attack or heart events. A 2002 study further suggested that flu shots might protect against stroke, although possibly not in patients older than age 75.

Treatment for atrial fibrillation always includes drugs (aspirin or warfarin) to prevent clots from forming. In addition to anticoagulants (blood thinners), other approaches may include:

Restoring or maintaining normal heart rhythm. This is accomplished with anti-arrhythmic drug, cardioversion procedures, or surgery to remove the defective area.
Controlling heart rate. Specific drugs are used for this approach.

Important studies report that controlling heart rate may be the preferable approach. In several studies, rhythm control offered no survival advantages and did not protect against ischemic stroke. Therapies aimed at controlling heart rate, furthermore, had fewer complications.

Drugs to Prevent Blood Clots

After a diagnosis of atrial fibrillation, warfarin (an anticoagulant) or aspirin (an antiplatelet) are essential to prevent blood clots. These drugs can reduce the risk for stroke by over 60% in patients with atrial fibrillation.

Warfarin (Coumadin) is the main anticoagulant (“blood thinner”) drug used to prevent strokes in high-risk patients with atrial fibrillation. Warfarin carries a risk for bleeding, but for most patients, warfarin’s benefits far outweigh its risks. The risk for bleeding is highest when warfarin therapy is first started, with higher doses, and with long periods of treatment. Patients at risk for bleeding are usually older and have a history of stomach bleeding and high blood pressure. It is important that patients who take warfarin have their blood checked regularly to make sure that it does not become “too thin.” Blood that is too thin increases the risk for bleeding, while blood that is “too thick” increases the risk for blood clots and stroke. Prothrombin time (PT) and international normalized ratio (INR) tests are used to monitor blood coagulation.
Aspirin is less effective than warfarin, but has a lower risk for bleeding. It is the preferred treatment for younger people with atrial fibrillation and for people who do not have other risk factors for stroke, such as high blood pressure or diabetes. Aspirin is also prescribed for higher risk patients who cannot tolerate anticoagulation therapy.
Researchers are investigating other drugs for preventing stroke and heart problems in patients with atrial fibrillation. These drugs include the antiplatelet medication clopidogrel (Plavix) and the angiotensin receptor blocker irbesartan (Avapro). Recent research indicates that anticoagulants such as warfarin (Coumadin) work better for atrial fibrillation patients than the combination of clopidogrel plus aspirin. Clinical trials are continuing to investigate whether clopidogrel alone is better than aspirin alone.

Restoring and Controlling Heart Rhythm

To initially restore heart rhythm, anti-arrhythmic drugs are usually tried first. If they fail to restore normal rhythm, cardioversion is often effective. (Some experts suggest trying cardioversion first to avoid side effects of the drugs.) Long-term maintenance therapy using anti-arrhythmic drugs may be required.

Electrical Cardioversion. Electrical cardioversion is mild shock therapy and is the current standard treatment used to restore normal heart rhythm. It is conducted as follows:

Anticoagulants (drugs used to prevent blood clotting) should be administered, if possible, at least 3 weeks before the procedure.
During the procedure, the patient must be conscious and, although sedated, can experience some pain from the procedure.

Although the stabilizing effect is usually only temporary, some evidence suggests that a series of cardioversion may succeed in maintaining normal rhythm in young healthy patients without the need for antiarrhythmic medications.

Low-energy implanted cardioverters (Atrioverter, Jewel AF) are being investigated for maintenance. Studies are promising.

Drugs Used for Maintaining Normal Heart Rhythm. For maintaining a stable rhythm, the following drugs may be used. The specific choices typically depend on whether or not the patient has existing heart disease:

For patients with no heart disease, the first choices include sotalol, flecainide, or propafenone, which are often used sequentially. If these fail, then amiodarone or a newer drug dofetilide (Tikosyn) may be tried. Others include ibutilide (Covert) and azimilide. If these drugs are not effective, other drugs tried include quinidine, procainamide, and disopyramide.
In patients with heart disease, amiodarone, dofetilide, or sotalol are commonly used depending on the cause of heart disease.

Amiodarone is more effective than most others and has been thought to be safer than many other similar drugs. Even in low doses, however, there is a high incidence of side effects, including thyroid disorders, neurologic, skin, and eye problems, and abnormally slow heart beats. Many of these drugs carry a small but significant increased risk, however, for a life-threatening arrhythmia called torsades de pointes. People with certain heart conditions should avoid these drugs.

Surgical Procedures for Complex AF. In some difficult cases, surgery may be recommended. The options and candidates depend on other complicating factors. The following are some examples:

AV node ablation involves severing the communication between the atria (the two upper chambers of the heart) and the ventricles (the two lower chambers). A pacemaker is then implanted just under the skin with electrodes leading to the ventricles. This approach is very effective, but it is irreversible and lifelong. Radiofrequency ablation may be an option in some patients.
A more aggressive procedure uses open chest surgery, in which a maze of cuts is made in the atria. As they heal, the scar tissue prevents the heart circuitry from misfiring. This technique controls atrial fibrillation in more than 90% of appropriate candidates. A new procedure is similar but less invasive.

Controlling Heart Rate

Drugs Used to Control Heart Rate. Beta-blockers or calcium channel blockers are used to control heart rate at the onset of atrial fibrillation. Digitalis, an older drug, is not used as often but can be effective in combination with the other drugs.

Diagnosis

Preventing a major stroke in people who experience transient ischemic attacks or small strokes requires determining the source of such attacks. A complete blood count, chest x-ray, and electrocardiogram are usually performed. Discouragingly, a 2001 study reported that over 30% of patients with TIA who called their primary care doctor were neither evaluated nor sent to the hospital within the month after a first event.

Examining the Carotid Artery. The doctor examines the carotid artery to determine if it is severely narrowed. If so, the patient is in danger of a major stroke. (The thickness of the carotid artery is also an important indicator for long-term risks for stroke, as well as heart disease and mortality rates in general.)

The doctor may use a number of approaches to determine the thickness of the artery:

An important clue to a blocked carotid artery is a bruit. This is a whooshing sound caused by blood flow turbulence in the narrowed artery. A doctor may be able to hear a bruit using a stethoscope. Occasionally, even a patient can hear the sound. The presence of a bruit, however, is not necessarily a sign of an impending stroke, nor does the absence of a bruit indicate an unblocked artery.
Carotid ultrasound is a very valuable tool for measuring the width of the artery. At this time, ultrasound is most useful in people between the ages of 40 and 60 years. Severely blocked carotid arteries may distort some measurements, so other tests may be required to confirm the results.
Measuring blood pressure to the eye may also be important in identifying problems in the carotid artery. If blood flow to the eye is reduced, it is likely that the carotid artery is severely narrowed.

Carotid duplex is an ultrasound procedure performed to assess blood flow through the carotid artery to the brain. High-frequency sound waves are directed from a hand-held transducer probe to the area. These waves "echo" off the arterial structures and produce a two-dimensional image on a monitor, which will make obstructions or narrowing of the arteries visible.

Imaging Techniques for TIAs. Several imaging techniques may identify small clots or other indicators of risk in the brain.

Identifying a Stroke Quickly. To save a patient's life, a fast diagnosis of both the presence and type of stroke is critical. Health professionals have devised different tests to help emergency workers quickly identify a person with stroke even before they reach the hospital. For example, an assessment tool called Face, Arms, Speech, Time (FAST) is highly accurate. It involves watching for the following signs:

(F)ACE. Ask the person to smile. Check to see if one side of the face droops.
(A)RMS. Ask the person to raise both arms. See if one arm drifts downward.
(S)PEECH. Ask the person to repeat a simple sentence. Check to see if words are slurred and if the sentence is repeated correctly.
(T)IME. If a person shows any of these symptoms, time is essential. It is important to get to the hospital as quickly as possible. Call 9-1-1. Act FAST.

Determining Ischemia Versus Hemorrhagic Stroke. Once a stroke has been identified, the next important step is to determine as quickly as possible whether it is hemorrhagic or ischemic. Clot-busting drug therapies can be life-saving for ischemic stroke patients, but they are effective only in the first 3 hours. In addition, they cause bleeding and can be lethal if the stroke is caused by a hemorrhage.

A computed tomography (CT) scan is essential for identifying or ruling out hemorrhagic strokes. The goal is to complete the CT examination and obtain and interpret the results within 45 minutes of arrival at the hospital. (An ultrasound technique called transcranial duplex sonography may be sensitive enough to differentiate between hemorrhagic and ischemic strokes if CT scans are not available.)

Certain factors suggest a hemorrhagic rather than ischemic stroke. They include specific symptoms (coma, vomiting, and severe headache), taking anticoagulants, very high systolic blood pressure, or high blood sugar levels in nondiabetics. However, such findings are not conclusive, and a CT scan or MRI is always needed.

Ruling Out Other Disorders. In most cases of stroke, the diagnosis is evident although a number of conditions may cause similar symptoms. These include seizures, infections that cause mental confusion, syncope (fainting), hypoglycemia, and brain tumors.

Magnetic Resonance Imaging (MRI). MRI uses a magnetic field to provide 3-dimensional images of the brain. In 2007, an important Lancet study of emergency room patients clearly indicated that MRI is superior to computed tomography (CT) in assessing whether a stroke has occurred. The MRI appears to work especially well for detecting ischemic stroke (stroke caused by blood clot). In the study, MRI accurately detected presence or absence of acute stroke in 80% of patients compared to 58% for CT. (Acute stroke included both ischemic and hemorrhagic types.) MRI detected acute ischemic stroke in 40% of patients compared to 10% for CT. In addition, MRI detected ischemic stroke within 3 hours of symptom onset (an important timeframe for delivering clotbuster drugs) in 46% of patients compared to only 7% for CT. Both MRI and CT performed similarly for detecting hemorrhagic stroke.

Computed Tomography. A computed tomography (CT) test uses x-ray images to take pictures of the skull and brain. Sometimes a dye is injected into a patient’s veins to enhance image contrast. Although research indicates that MRI is better in determining ischemic stroke, CT still may be useful in diagnosing hemorrhagic strokes.

Ultrasound. Ultrasound may be used in different circumstances. This imaging technique is painless and noninvasive.

Carotid ultrasound (also called Doppler or duplex sonography) can determine blockage in the carotid arteries that could lead to or be causing a stroke.
Transcranial duplex sonography can identify blockage in large arteries in stroke patients and to monitor the effects of thrombolytic therapy.

Cerebral Angiography. Cerebral angiography is an invasive procedure that may be used for patients with TIAs who require surgery. It can also detect aneurysms and monitor thrombolytic therapy. It requires the insertion of a catheter into the groin, which is then threaded up through the arteries to the base of the carotid artery. At this point a dye is injected, and x-rays, CTs, or MRI scans determine the location and extent of the narrowing, or stenosis, of the artery. In people with TIAs the risk of stroke itself increases using this technique, particularly in elderly people with diabetes.

Other Techniques. Other imaging tests, including positron-emission tomography (PET) and single photon-emission computed tomography (SPECT), may also help the doctor identify injuries caused by the stroke.

Electrocardiogram (ECG). A heart evaluation using an electrocardiogram (ECG) is important in any patient with a stroke or suspected stroke. An ECG records the electrical current in the heart muscle.

Echocardiogram. An echocardiogram uses ultrasound to view the chambers and valves of the heart. It is generally useful for stroke patients to identify blood clots or risk factors for blood clots that can travel to the brain and cause stroke. There two are types:

Transthoracic echocardiograms (TTE) view the heart through the chest. It is noninvasive and is the standard approach.
Transesophageal echocardiogram (TEE) examines the heart using an ultrasound tube that the patient literally swallows and passes down the throat. It is uncomfortable and requires sedation. It is typically used to obtain more accurate images of the heart if a TTE has suggested abnormalities, such as atrial fibrillation or patent foramen ovale (PFO).

Patients who have a TIA are at increased risk for a major stroke in the days and weeks that follow. The ABCD² score is a tool that helps doctors predict short-term stroke risk following a TIA. The ABCD² score assigns points for various factors:

Age (over 60 years)
Blood pressure (greater or equal to 140/90 mm Hg)
Clinical features (weakness on one side of the body; speech impairment without weakness
Duration of TIA symptoms (at least 60 minutes)
Diabetes

Based on the number of points, a doctor can identify whether a patient is at low, moderate, or high risk of having a subsequent stroke within 2 days after a TIA. Several 2006 and 2007 studies indicated that the ABCD² score works well in predicting stroke, and can help doctors better decide which patients require hospitalization and emergency care.

Blood Tests. Several blood tests may help predict the risk for a stroke and determine the severity and complications of an existing stroke.

Specific blood tests are important to determine clotting times, to check electrolytes (potassium, calcium, sodium), and to measure factors indicating liver or kidney problems. Kidney tests measure blood proteins that are filtered through the kidneys. These proteins include creatinine and blood urea nitrogen (BUN). A more recent type of kidney test measures the protein cystatin C. Recent research suggests that the cystatin C kidney test may be better at predicting cardiovascular risks in elderly patients.
Blood sugar (glucose) levels are measured. Hyperglycemia (high levels) may indicate a worse outcome for some strokes (although not hemorrhagic or lacunar strokes). Hypoglycemia (low levels) is a common complication of diabetes treatments, and its symptoms may mimic those of a stroke.
A new blood test, the PLAC test, was approved in 2005 to help diagnose people at increased risk for ischemic stroke. The PLAC test measures an enzyme called lipoprotein-associated phospholipase A2 (Lp-PLA2). Patients with high levels of this protein have twice the risk for ischemic stroke as patients with normal levels.

Examination of Spinal Fluid. If the CT scan is negative but the doctor still suspects a subarachnoid hemorrhagic stroke, a spinal tap may be performed. Spinal fluid containing significant amounts of blood will usually confirm a hemorrhagic stroke.

Managing a Stroke

Until recently, the treatment of stroke was restricted to basic life support at the time of the stroke and rehabilitation later. Now, however, treatments can be dramatically beneficial when administered as soon as possible after the onset of the stroke. It is critical to get to the hospital and be diagnosed as soon as possible. There are several steps in the initial assessment and management of a person with a stroke.

If significant symptoms appear in people at risk for stroke, calling 911 is critical (as opposed to calling the family doctor or trying to get the patient to the hospital by car). One study reported that patients who went to the emergency room in an ambulance had a much shorter delay in getting treatment than those who went on their own. Receiving treatment early is critical in reducing the damage from a stroke.

Important diagnostic and evaluation steps are needed for the optimal treatment of a stroke patient:

Determine Whether the Stroke Is Ischemic or Hemorrhagic. As soon as the patient enters the hospital, diagnostic tests, particularly a CT scan, should occur to determine whether the stroke is ischemic or hemorrhagic.

Determine The Need for Thrombolytic Drugs. If the stroke is ischemic, the next step is to determine if the patient would benefit from blood clot-busting drugs (called thrombolytics). The following factors can assist in making this decision:

Estimate the time of onset of the stroke. Time is critical in the decision-making process. Clot-buster drugs do not generally help if given more than 3 hours after stroke onset. Onset is when the patient first experiences any symptoms, even minor impairment. If the patient had a previous TIA that completely resolved before the stroke, however, onset is dated from when the more recent symptoms developed.
Tell the doctor if the patient has been taking any blood-thinning drugs.
Give the doctor a thorough history of any accompanying medical or physical condition and any recent event, such as surgery or injury, which might contribute to the condition.
CT scans will indicate if there are extensive early injuries, which might affect the decision to use these drugs.

The patient should receive treatment to support basic life functions and to reduce stress, pain, and agitation. The following steps are also very important:

Maintain Adequate Delivery of Oxygen. It is very important to maintain oxygen levels. In some cases, airway ventilation may be required. Supplemental oxygen may also be necessary for patients when tests suggest low blood levels of oxygen. Hyperbaric oxygen (which is oxygen administered under pressure) may help specific stroke patients, although it is not recommended for most patients, since there is some risk of significant adverse effects using this approach.

Managing Fever and Lowering Body Temperature (Hypothermia). Fever should be aggressively treated, since strong evidence suggests that its presence predicts a poorer outlook. Some evidence suggests that hypothermia -- reducing body temperature -- might protect nerve cells in stroke patients. Cooling is done through special cooling blankets, ventilators, or infusion of cool fluids. Unfortunately, severe side effects occur with even moderate hypothermia (86°F, 30°C), which can include pneumonia, blood clotting disorders, heart rhythm disturbances, and others.

Maintain Electrolytes. Maintaining a healthy electrolyte balance (the ratio of sodium, calcium, and potassium in the body's fluids) is critical.

Managing Blood Pressure. Managing blood pressure is essential and complicated. Patients with stroke and pressures above 220 (systolic) or 120 (diastolic) should be treated. Lowering blood pressure too quickly can be dangerous, however, in patients with both ischemic and hemorrhagic strokes. In general, experts do not advise aggressively lowering elevated pressures below 220/120 mm Hg in patients unless they have other conditions, such as a heart attack, that require pressure-lowering treatments. In patients who require thrombolytic drugs, blood pressure should cautiously be lowered to 185/110 mm Hg. In most cases, blood pressure declines when these patients become stabilized.

Managing Increased Brain Pressure. Hospital staff should watch carefully for increased pressure on the brain, which is a frequent complication of hemorrhagic strokes. It can also occur a few days after ischemic strokes. Early symptoms of increased brain pressure are drowsiness, confusion, lethargy, weakness, and headache. Medications such as mannitol may be given during a stroke to reduce pressure or the risk for it.

Keeping the top of the body higher than the lower part, such as by elevating the head of the bed, can reduce pressure in the brain and is standard practice for patients with ischemic stroke. However, this practice also lowers blood pressure in general, which may be dangerous for patients with massive stroke.

Monitoring the Heart. Heart attack and arrhythmias are potential complications of ischemic stroke. Patients must be monitored using electrocardiographic tracings.

Controlling Glucose Levels. Elevated blood sugar (glucose) levels can occur with severe stroke and may be a marker of serious trouble. In general, it is advisable to lower glucose levels that are about 300 mg/dL, usually with insulin. It is not clear, however, if glucose-lowering treatments offer any advantage. Excessive lowering of glucose levels can have damaging effects on the brain. Studies are underway to determine the best approach.

Medications

Intravenous Thrombolytics. Clot-busting (thrombolytic) drugs break up existing blood clots. They are among the important treatments for heart attacks, and are now also used for ischemic (not hemorrhagic) stroke. While research has confirmed that early treatment with thrombolytics can greatly increase a stroke patient's chances for recovery, their use has been limited due to the short treatment window (within 3 hours of onset of stroke symptoms). The standard thrombolytic drugs are tissue plasminogen activators (t-PAs). They include alteplase (Activase) and reteplase (Retavase).

The following steps are critical before administering these clot-buster drugs:

Before the thrombolytic is given, a CT scan must first confirm that the stroke is not hemorrhagic. If the stroke is ischemic, a CT scan can also suggest if injuries are very extensive, which might affect the use of thrombolytics.
Thrombolytics must be administered within 3 hours of a stroke to have any effect. According to a 2004 review of clinical trials, best results are achieved if patients are treated with 90 minutes of a stroke. Unfortunately, most stroke patients arrive at the hospital more than 3 hours after an attack and therefore are not eligible for treatment. There is some evidence that t-PA administered with 4 hours may also be effective, but more research needs to be conducted. These findings underscore the critical need for people to go to a hospital immediately if a stroke is suspected.

Thrombolytics carry a risk for hemorrhage, so they may not be appropriate for patients with existing risk factors for bleeding. They should not be used in patients who are experiencing seizures. The drug may be appropriate in more patients than previously thought, however, including older people, those with a history of stroke, and those with high blood pressure. Although older studies cited concern over the safety and effectiveness of t-PA, a 2004 review of clinical trial data found that patients who received t-PA were two times more likely to experience a favorable outcome than those who did not receive this treatment.

Intra-Arterial Thrombolytics. Researchers are investigating thrombolytics injected directly into an artery in the brain. Early studies suggest this approach may allow effective treatment up to 6 hours after a stroke and improve recovery in more patients. The risk for bleeding and hemorrhagic stroke is significantly increased, however.

Fibrin-Depleting Drugs. These drugs deplete the amount of fibrinogen in blood, which in turn reduces the "stickiness" in blood. Such drugs include ancrod and batroxobin (Defibrase), both derived from the venom of poisonous snakes. Some experts believe these drugs might be a possible alternative to thrombolytics. Studies suggest they may modestly reduce the risks for death and disability if given early on. As with all anti-clotting drugs, there is a higher risk for hemorrhage, but it appears to be slight.

Medications that prevent blood from clotting are used to prevent a recurring or second stroke. Anticlotting drugs include antiplatelets and anticoagulants.

Antiplatelet Drugs.Blood platelets are involved in blood clotting. Antiplatelets prevent clotting by blocking the accumulation of platelets. An antiplatelet drug -- most often aspirin -- is given within 48 hours of an ischemic stroke and continued in low doses as maintenance therapy. Studies suggest that antiplatelet therapy can reduce the risk for a second stroke by 25%.

Aspirin. Aspirin is recommended within 48 hours of a first ischemic stroke in doses of 50 - 325 mg. Daily low-dose aspirin may also help prevent a second ischemic stroke. Experts also recommend aspirin combined with the antiplatelet drug dipyridamole (Aggrenox). A 2006 study indicated that aspirin plus dipyridamole may be better than aspirin alone in preventing a heart attack or major stroke in patients who have had a minor ischemic stroke. Patients should not be given an aspirin until a diagnosis of ischemic or hemorrhagic stroke has been determined. Aspirin increases the risk for bleeding in patients with hemorrhagic stroke and can be dangerous.
Thienopyridines. Clopidogrel (Plavix) and ticlopidine (Ticlid) are antiplatelet drugs known as thienopyridines. (Clopidogrel is preferred over ticlopidine because of its better safety record.) Evidence suggests that clopidogrel plus aspirin is better than aspirin alone in reducing blood clots in patients who have carotid artery blockage (carotid stenosis). Other studies indicate that clopidogrel alone may be sufficient for patients who have had a recent ischemic stroke or TIA. A study of over 7,000 of these patients found that adding aspirin to clopidogrel therapy provided no additional benefit and increased the risk of bleeding; therefore, aspirin plus clopidogrel is not usually recommended for most patients who have had an ischemic stroke or TIA. Clopidogrel alone may also be better than aspirin alone in preventing a third stroke or heart attack in high-risk patients.
Glycoprotein IIB/IIIa Inhibitors. Glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors are sometimes administered intravenously in the hospital and include abciximab (ReoPro, Centocor), eptifibatide (Integrilin), tirofiban (Aggrastat), lotrafiban, and lamifiban. They are being investigated alone or as additions to thrombolytic (clot-busting) drugs.

Anticoagulants.Anticoagulants thin blood and may be useful under certain circumstances.

Warfarin. The anticoagulant warfarin (Coumadin) may not work as well as aspirin in preventing a second stroke in people who have partial artery blockage in the brain (intracranial stenosis). Warfarin is, however, very important in high-risk patients with atrial fibrillation. It may be useful in other situations, such as patients with patent foramen ovale (PFO), those whose stroke followed a heart attack, or in high-risk patients who cannot take antiplatelet drugs.
Heparin. Intravenous heparin, a potent anti-platelet drug, has been used for ischemic stroke since 1941. Although many doctors continue to use it, five out of six major studies have reported no clear protective benefits compared to aspirin with the use of standard heparin or any heparin-like drugs. They also pose a much higher risk for hemorrhagic stroke. Experts now recommend heparins only for preventing thromboembolism in stroke patients at risk for this condition.
Direct Thrombin Inhibitors (DTIs). Direct thrombin inhibitors are a more recent group of anti-coagulants. The first DTI is hirudin, a natural substance derived from the saliva of leeches. New forms include argatroban (Novastan), bivalirudin (Angiomax), danaparoid (Orgaran), lepirudin (Refludan), desirudin (Revasc), inogatran, and efegatran. Ximelagatran (Exanta) is new oral drug that is showing great promise for protection against stroke in patients with atrial fibrillation while posing a low risk for bleeding.

All anti-clotting drugs carry a risk for bleeding and a slightly increased risk for hemorrhagic stroke.

It is important that patients control their high blood pressure and LDL (“bad”) cholesterol levels. Various drugs, such as statins, diuretics, and ACE inhibitors, can manage these conditions. People with diabetes should also maintain tight control of their blood sugar levels.

Calcium Channel Blockers. Early administration of calcium channel blockers, such as nimodipine (Nimotop), can improve functional outcome. One of the most common and serious dangers after a subarachnoid hemorrhagic stroke is spasm of the blood vessels near the ruptured site, which closes off oxygen to the brain. Calcium causes contraction of the smooth muscles of the blood vessels; calcium channel blockers are drugs that relax the blood vessels. The drugs work best if they are administered within 6 hours of the stroke. Calcium channel blockers are not useful for ischemic strokes, although they can be used in combinations with blood pressure lowering drugs to prevent them.

Nerve-Protecting Drugs. More than 50 medications have been studied in clinical trials aimed at slowing or preventing the cascading process that destroys nerve cells after a stroke. Many investigative drugs are targeting the excitatory amino acids, such as glycine and glutamate, which are known to destroy nerve cells after a stroke. Although none to date have proven to have any significant benefits, some are showing promise. They include magnesium sulfate, citicoline, ebselen, piracetam, edaravone, albumin, erythropoietin, and NXY-059.

Investigative Drugs for Nerve Regeneration. Scientists used to think that when cells in the brain were destroyed, new ones could not grow to replace them. Researchers have now observed, however, that nerve regrowth (neurogenesis) can occur in the adult human brain. This exciting discovery opens the way for new drugs that might in the future stimulate nerve growth and repair damage done by many neurologic diseases, including stroke. For example, a 2002 study reported nerve regeneration in animals whose brains were treated with the drug inosine. More research is underway.

Surgery

Carotid endarterectomy is a surgical procedure that cleans out and opens up the narrowed carotid artery. It is used in patients at high risk for thrombotic ischemic strokes, which are caused by blockages in the internal carotid artery. It is also sometimes used after a stroke. In such cases, patients have reported improvements in vision, speech, swallowing, functioning of arms and legs, and general quality of life.

There is a risk of a heart attack or stroke from the procedure. Anyone undergoing this procedure should be sure their surgeon is experienced in recent techniques and that the medical center has complication rates of less than 6%. A 2000 study reported that older surgeons had a worse record than younger ones, possibly because they relied on residents or were less likely to adopt new procedures.

Procedure Description. The procedure generally is as follows:

The patient is usually given general anesthesia, although it has been reported that using local anesthetic is just as safe and reduces the cost of the procedure.
A bypass tube is put in place to transport blood around the blocked area during the procedure.
The surgeon scrapes away the plaque on the arterial wall.
The artery is sewn back together, and blood flow is restored.
The patient generally stays in the hospital for about 2 days. There is often a slight aching in the neck for about 2 weeks, and the patient should refrain as much as possible from turning the head during this period.

Endarterectomy is a surgical procedure removing plaque material from the lining of an artery.

Click the icon to see an illustrated series detailing surgery for unblocking carotid arteries.

Determining Who Should Have Surgery. Evidence strongly suggests that most patients with severe stenosis (over 70% of the carotid artery is obstructed) can benefit from either carotid endarterectomy or carotid artery stenting. An experienced surgeon with a good track record is essential. Patients with mild stenosis (less than 50% obstruction) should not have endarterectomy; these patients do better with medications even if they have symptoms. For patients with moderate stenosis (50 - 69%), the decision to perform surgery needs to be determined on an individual basis. When a carotid endarterectomy procedure is recommended, it should be performed within 2 weeks.

Carotid angioplasty and stenting (CAS) is being investigated as a less-invasive alternative to carotid endarterectomy. It is based on the same principles as angiography done for heart disease.

An extremely thin catheter tube is inserted into an artery in the groin.
It is threaded through the circulatory system until it reaches the blocked area in the carotid artery.
The doctor either breaks up the clot or inflates a tiny balloon against the blood vessel walls (angioplasty).
After temporarily inflating the balloon, the doctor typically leaves a circular wire mesh (stent) inside the vessel to keep it open.

This procedure carries a risk for an embolic stroke and other complications. At this time, it is being used in some centers as an alternative to endarterectomy in patients who cannot undergo endarterectomy, especially for patients with severe stenosis (blockage greater than 70%) and high surgical risk. Several studies published in 2006 suggested that CAS should be used only for patients with these types of conditions. One of these trials, EVA-3S, was stopped early because results clearly indicated a higher 30-day risk of death and stroke in patients who underwent CAS. Experts are waiting for results of further trials comparing stenting and endarterectomy.

Hemicraniectomy is surgical removal of a bone patch from the skull to relieve pressure. The bone is stored under sterile conditions and reimplanted a few months latter. It may have be a life-saving option for some patients with severe stroke that has resulted in swelling and injury to a large area in the brain. Studies are showing some benefits for high-risk patients, but more information is needed to determine specific conditions that will respond to this treatment.

Extracranial-intracranial (EC-IC) bypass has been under investigation for decades for ischemic stroke, but has had very mixed results, some extremely negative. With this procedure, a healthy artery in the scalp is rerouted to an area of the brain that was deprived of blood because of a blocked artery. This procedure is now sometimes used for patients with aneurysms. Some experts hope, however, that, in specific cases chosen via careful imaging and using the latest surgical techniques, EC-IC may prove to be helpful for some stroke patients.

Surgical Intervention of the Ruptured Aneurysms. In patients with subarachnoid hemorrhagic stroke, surgery to block off the aneurysm is usually recommended within a few days of the stroke. The standard procedure is to clip the aneurysm and stop bleeding. Alternative approaches are promising.

Surgical Intervention of Unruptured Aneurysms. If an unruptured aneurysm is detected, patients should discuss all options with their doctor, including surgical repair. Unruptured aneurysms occur in between 1 - 8% of the general population, however, and controversy exists over when to operate and on which patients.

In general, the decision rests on the size of the aneurysm, but uncertainty still exists. In one study, for example, the risk of rupture for aneurysms between 10 - 25 mm was quite low -- slightly less than 1% per year for both groups. Aneurysms over 25 mm, however, had a 6% chance of rupturing within a year. Studies have reported that in general, the risk for rupture is between .05 - 2% a year, but recent evidence suggests that the risks may be even less. In one study, even people with a history of subarachnoid hemorrhage had only a 0.5% annual risk for recurrence when aneurysms were small.

Aneurysms can often cause symptoms, however, even if they do not rupture. Patients should discuss their particular risk factors carefully with their doctors. Individuals with arteriovenous malformation, a condition caused by abnormal associations between arteries and veins, should be monitored for the development of an aneurysm.

Clipping the Aneurysm. The standard surgical procedure for treating a ruptured aneurysm is to place a clip across the neck of the aneurysm, which blocks off bleeding. It is usually performed within the first 3 days. Getting to the aneurysm is often extremely difficult. Deep cooling of the body to stop circulation may be used to allow more time for the operation. Procedures that remove large portions of the bone in the skull are being developed to allow fast access. There is a relatively high risk for newly formed aneurysms, particularly after 9 years. Patients may want to discuss follow-up angiography to detect any new aneurysms 9 - 10 years after the procedure.

Transcatheter Embolization for Sealing off the Aneurysm. Transcatheter embolization is a new technique for ruptured and unruptured aneurysms that is proving to be effective, although it is still investigational. The surgeon threads a thin tube through the artery leading to the aneurysm through which materials are passed to plug or obstruct the aneurysm. In one version of this procedure, the following occurs:

A tiny platinum coil is inserted through the tube and positioned into the aneurysm.
An electric charge is passed through the coil to form blood clots.
In this case, blood clots benefit the patient by using the coil as a scaffold and sealing off the aneurysm.

A 2002 study suggested it could be attempted safely in over 95% of patients with unruptured aneurysms. In the study, the procedure eliminated the aneurysm in nearly 90% of the patients. In small trials using the coil with a ruptured aneurysm, only 3.7% of patients suffered a second stroke after 7 months compared to the usual re-rupture rate of 30 - 40%.

Emergency Surgery for Hemorrhagic Strokes. Emergency surgery for a hemorrhagic stroke involves locating and removing large blood clots. In the past, such procedures had little effect on survival. Advances, however, are improving outcomes when surgery is performed very early.

Recovery

After a stroke, patients should take all necessary measures, including medications and lifestyle changes, to prevent another stroke. For those whose stroke was ischemic, aspirin, warfarin, or both will usually be prescribed.

Having a neurologist as the primary doctor after a stroke, rather than some other specialist or primary care doctor, significantly increases the chance for survival. Patients or their families should be persistent in requesting the best care possible during this important early period.

Receiving initial treatment at a stroke unit, instead of a general ward, plays a strong role for better long-term quality of life. Rehabilitation services aimed at patients living at home are also very effective in improving independence. Patients or their families should seek patient advocates or support associations to ensure they receive the right care.

In addition to problems brought on by neurologic damage, stroke patients are also at risk for other serious problems that reduce their chances for survival. They include:

Blood clots in the legs (deep vein thrombosis)
Pulmonary embolism (a blood clot that travels to the lungs)
Pneumonia
Widespread infection
Heart problems
Urinary tract infections (a catheter is sometimes used in the first 48 hours after stroke to help with urinary retention, but if it is left in longer it can cause urinary tract infections)

Measures should be taken to monitor and treat patients for these important problems.

In all, 90% of stroke survivors experience varying degrees of improvement after rehabilitation. The current cost-cutting climate generates pressure to send elderly patients who have had a stroke directly to a nursing home rather than a rehabilitation first. Not all patients, however, need or benefit from formal rehabilitation:

If the stroke is severe, intensive training would not be helpful.
If the stroke is mild, patients often improve on their own.

Positive factors that help predict good candidates for rehabilitation:

A patient should be able to sit up for at least an hour.
The patient should be able to learn and be aware.
Spasticity may be a good sign, because it indicates live nerve action.
Patients who are able to move their shoulders or fingers within the first 3 weeks after having a stroke are more likely to recover the use of their hands than patients who cannot perform these movements. The ability to feel light pressure on the affected hand, however, makes no difference for future hand movement.
Family members or close friends are available to be active participants in the rehabilitation process.

Factors that predict a poor response to rehabilitation:

Dysphagia (the inability to swallow) is associated with a higher mortality rate, possibly because of increased risk for infection and malnutrition. Dysphagic patients are given nutrition using a stomach tube or a feeding tube inserted down through the nose.
Incontinence.
The inability to recognize nonspeech sounds that occur right after a stroke.
A poor hand grip that is still present after 3 weeks is an indicator of severe problems.
Having had very severe seizures after the stroke.

Factors that do not rule out rehabilitation:

About 30% of patients experience aphasia (an impaired ability to speak). However, this disability does not necessarily affect the ability to think. Aphasia can also be temporary.
Although confusion is common among people who have had strokes, partial or even complete recovery is very possible.

Physical therapy should be started as soon as the patient is stable, as early as 2 days after the stroke. Some patients will experience the fastest recovery in the first few days, but many will continue to improve for about 6 months or longer. Because stroke affects different parts of the brain, specific approaches to managing rehabilitation vary widely among individual patients:

Exercise program. Recent guidelines from the Veteran’s Administration recommend that patients get back on their feet as soon as possible to prevent deep vein thrombosis. Patients should try to walk at least 50 feet a day. Assisted devices or bracing are sometimes used to help support the legs. Treadmill exercises can be very helpful for patients with mild-to-moderate dysfunction. Exercise should be tailored to the stroke survivor's physical condition and can include aerobic, strength, flexibility, and neuromuscular (coordination and balance) activities.
Retraining muscles. Stretching and range-of-motion exercises are used to help treat spastic muscles. They can also help patients regain function in a paralyzed arm. There are several approaches. The Bilateral Arm Training with Rhythmic Auditory Cueing (BATRAC) technique involves moving a bar with both arms in a sustained rhythmic pattern. A 2004 study in the Journal of the American Medical Association (JAMA) reported that BATRAC helped patients get back use of their paralyzed arm. Patients had a stroke at least 4 years before participating in the BATRAC study. Another technique, constraint-induced movement therapy (CIMT), involves doing a series of repetitive exercises while the less functional arm is restrained. Research published in 2006 in JAMA indicated that 2 weeks of CIMT can help patients regain arm function. Patients in the CIMT study had experienced a stroke within the prior 3 - 9 months.
Speech therapy and sign language. People who have had a stroke often have aphasia, a brain condition that makes it difficult to speak and understand language. Aphasia can come in many different forms. A person may be unable to speak at all, or just have difficulty saying the right word. Intense speech therapy after a stroke is important for recovery. Some experts recommend 9 hours a week of therapy for 3 months. A 2005 study indicated that a shorter period (3 hours a week for 10 days) also works well. Language skills improve the most when family and friends help reinforce the speech therapy lessons.
Biofeedback techniques combined with physical therapy. This combination has been beneficial in certain cases. Electrical stimulation of the throat, for example, may help patients with dysphagia recover their ability to swallow faster. Stimulation of the wrist and finger is also showing promise for improving motor capabilities.
Swallowing exercise. A promising study reported that swallowing improved when patients performed a simple exercise 3 times a day for 6 weeks. They lay flat and raised their heads three times, holding them up for 1 minute with a 1 minute rest in between. This was followed by 30 consecutive head lifts.
Attention training. Problems with attention are very common after strokes. Direct retraining teaches patients to perform specific tasks using repetitive drills in response to certain stimuli. (For example, they are told to press a buzzer each time they hear a specific number.) A variant of this approach trains patients to relearn real-life skills, such as driving, carrying on a conversation, or other daily tasks.
Occupational training. Occupational therapy is important and improves daily living activities and social participation.

Drug therapy can sometimes help relieve specific effects of stroke:

Dantrolene (Dantrium), tizanidine (Zanaflex), and baclofen (Lioresel) are used to treat spasticity.
Heparin, a blood-thinning drug, is used to prevent blood clots from forming in the veins of the legs (thrombosis).
Some patients experience constant hiccups, which can be very serious. Among the drugs used for this condition are chlorpromazine or baclofen.
Studies have reported that dextroamphetamine or methylphenidate (Ritalin), an amphetamine used in attention deficit disorder, may help patients recover speech and motor skills when combined with physical therapy.

Certain drugs commonly taken for conditions associated with stroke may actually slow recovery. They include drugs used for high blood pressure, including clonidine and prazosin, anticonvulsant drugs, the antipsychotic drug haloperidol, and anti-anxiety drugs such as benzodiazepines.

The Emotional State of the Patients. Strong motivation with the goal of independence after rehabilitation is important for recovery. Unfortunately, depression is very common after a stroke, both as a direct and indirect result of the stroke:

Strokes that affect the right hemisphere in the brain increase the risk for depression.
Patients can become depressed by the changes in their ability to function.
A peculiar stroke-induced condition, known as post-stroke crying or neurologic emotionalism, is a neurologic not a psychologic disorder.

If depression is prolonged, it can interfere with recovery. One study showed that people who suffered strokes and became depressed were three times more likely to die within 10 years than stroke victims who were not depressed. There is a significantly increased risk of suicide in patients with stroke, especially in women and those under age 60.

Antidepressants, particularly fluoxetine (Prozac) and similar so-called SSRI drugs, have been beneficial in relieving post-stroke crying as well as improving recovery in general and mood in particular. Antidepressants may also help restore mental abilities.

Some doctors also recommend tricyclic antidepressants, which include amitriptyline (Elavil) and nortriptyline (Pamelor). In one study nortriptyline (Pamelor) not only improved mood but also had positive effects on mental functioning, suggesting perhaps that some dementia associated with stroke may actually be due to depression. Tricyclics may also be useful for neurologic emotionalism.

Anxiety disorder is also common and debilitating. Some research indicates that many patients suffer from feelings identical to post-traumatic stress syndrome. The two disorders often overlap, but drug treatments for each differ and may offset the other.

Many drugs for psychologic disorders affect the central nervous system and can delay rehabilitation. Skilled professional help is needed to determine the most effective and safest treatments.

The Emotional State of the Caregiver. The caregiver's emotions and responses to the patient are critical. Patients do worse when caregivers are depressed, overprotective, or not knowledgeable about the stroke. Unfortunately, in one study, over half of the caregivers themselves were depressed, particularly if the stroke victims were left with dementia or abnormal behavior.

Resources

www.strokeassociation.org -- American Stroke Association
www.americanheart.org -- American Heart Association
www.stroke.org -- National Stroke Association
www.ninds.nih.gov -- National Institute of Neurological Disorders and Stroke
www.aphasia.org -- National Aphasia Association
www.aan.com -- American Academy of Neurology
www.strokecenter.org/trials -- Stroke Trials Directory

References

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Amarenco P, Bogousslavsky J, Callahan A 3rd, Goldstein LB, Hennerici M, Rudolph AE, et al. High-dose atorvastatin after stroke or transient ischemic attack. N Engl J Med. 2006 Aug 10;355(6):549-59.

Chalela JA, Kidwell CS, Nentwich LM, Luby M, Butman JA, Demchuk AM, et al. Magnetic resonance imaging and computed tomography in emergency assessment of patients with suspected acute stroke: a prospective comparison. Lancet. 2007 Jan 27;369(9558):293-8.

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Mas JL, Chatellier G, Beyssen B, Branchereau A, Moulin T, Becquemin JP, et al. Endarterectomy versus stenting in patients with symptomatic severe carotidstenosis. N Engl J Med. 2006 Oct 19;355(16):1660-71.

Rosamond W, Flegal K, Friday G, Furie K, Go A, Greenlund K, et al. Heart disease and stroke statistics -- 2007 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation. 2007 Feb 6;115(5):e69-171. Epub 2006 Dec 28.

SPACE Collaborative Group; Ringleb PA, Allenberg J, Bruckmann H, Eckstein HH, Fraedrich G, et al. 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: a randomised non-inferiority trial. Lancet. 2006 Oct 7;368(9543):1239-47.

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Wolf SL, Winstein CJ, Miller JP, Taub E, Uswatte G, Morris D, et al. Effect of constraint-induced movement therapy on upper extremity function 3 to 9months after stroke: the EXCITE randomized clinical trial. JAMA. 2006 Nov 1;296(17):2095-104.

Review Date:
4/16/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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