Diagnosis Coronary Artery Disease

Diagnosis: Coronary Artery Disease

Dear Reader,

If you recently discovered that you have coronary artery disease, a common form of heart disease, you may feel overwhelmed and distressed, especially if your diagnosis came after an unexpected heart attack. But you’re far from alone. Approximately 80 million people in the United States have some form of heart disease, and for about half of them, a heart attack is the first manifestation of the illness. Even more sobering is the fact that half of those people die on the spot, without ever making it to the hospital.

Still, there are reasons for optimism. First, advances in diagnosis and treatment have led to a dramatic drop in the rate of deaths from heart disease. Since 1999, this rate has fallen by a third. Second, even if you have heart disease, there’s a great deal you can do to lessen your odds of a first or second heart attack.

Most heart attacks result from atherosclerosis—the hardening and narrowing of arteries that supply the heart. This progressive condition starts early in life and is influenced by a wide range of factors, including both the genes you inherit and the lifestyle choices you make. But if you’re like most people, you have at least one major risk factor for future heart trouble that’s within your power to change, such as lack of exercise, high blood pressure, cigarette smoking, or abnormal cholesterol levels. Surefire ways to lessen your risk of further heart problems are maintaining a healthy weight, getting regular exercise, and eating plenty of colorful fruits, vegetables, and fiber-rich whole-grain foods.

The special section of this report explains how to make these potentially lifesaving changes, and it details the latest research showing how sleep problems and various types of stress contribute to heart disease. This report also features a risk calculator to help predict your odds of having a heart attack or stroke, needing bypass surgery or angioplasty, or experiencing another kind of cardiovascular “event” over a 10-year period, along with descriptions of what to expect from various diagnostic tests and procedures for heart problems, and finally a detailed guide to medications for the heart.

To your health,
Peter Stone, MD
Medical Editor

If you’ve just been diagnosed with coronary artery disease, you probably have a lot of questions, including the most basic ones: What is this condition? How serious is it? What can I do to treat it?

Heart disease, also known as cardiovascular disease, is a broad term that encompasses a variety of problems with the circulatory system, from high blood pressure to stroke. But most of the time when people speak of heart disease, what they really mean is coronary artery disease—a narrowing of the coronary arteries, resulting in reduced blood flow to the heart muscle. In the United States, coronary artery disease is by far the most prevalent type of life-threatening cardiovascular disease. People often become aware they have the condition when they experience chest pain brought on by exertion or stress (angina) or when they suffer a heart attack (myocardial infarction).

Figure 1: Supplying the heart

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It’s often said that the heart is the size of your fist, but it’s actually closer to the size of two fists. The aorta, the body’s largest blood vessel, is almost the diameter of a garden hose. A network of coronary arteries, each about as thick as a strand of spaghetti, emerges from the aorta. These arteries branch into smaller and smaller vessels that eventually penetrate the heart muscle, supplying it with oxygen and nutrients. This illustration shows the main coronary arteries (for simplicity’s sake, the veins are not pictured). The lighter-shaded vessels represent those that wrap around the back of the heart.

The coronary arteries are so important because they supply the heart muscle itself with the nutrient- and oxygen-rich blood it needs to function. The heart depends on two main arteries, the right and left coronary arteries, for its entire blood supply. The left coronary artery splits into the left anterior descending artery (sometimes called the “widow maker” because it provides blood to the left ventricle, the heart’s main pumping chamber) and the circumflex artery. Like the branches of a tree, these arteries divide into progressively smaller blood vessels (see Figure 1). Any of the coronary arteries can be narrowed by a buildup of fatty plaque, known medically as atherosclerosis. This term combines two Greek words, athere (porridge) and sclerosis (hardening). The name is accurate: in atherosclerosis, the artery walls become filled with soft, mushy deposits that eventually make the artery hard, stiff, and narrow. These deposits can restrict blood flow, which deprives the heart of needed oxygen (a condition called ischemia). A partial or temporary reduction in blood supply, producing mild ischemia, can lead to angina. Severe or prolonged ischemia, usually due to a clot formed after the rupture of a plaque, causes a heart attack and the death of heart muscle cells (see Figure 2).

Figure 2: From healthy artery to heart attack

Heart attacks aren’t just the result of a buildup of fatty plaque in the arteries. Inflammation triggered by damage to the inner lining of an artery sets off the steady growth of atherosclerotic plaque, which can suddenly rupture, causing a heart attack.

Stage 1 Excess LDL passes through the artery

Cholesterol travels in the bloodstream within spherical particles called lipoproteins. About two-thirds of blood cholesterol is in the form of low-density lipoprotein (LDL), often called “bad” cholesterol, because excess LDL leaves the blood and lodges in the artery walls. The higher your LDL, the greater your risk for atherosclerosis. So-called “good” cholesterol, or high-density lipoprotein (HDL), carries cholesterol away from the arteries to the liver, where it’s eventually eliminated from the body via the digestive tract. HDL also helps keep blood vessels dilated and fights inflammation, minimizing blood vessel injury caused by LDL.

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Stage 2 Plaque builds up and the artery narrows

LDL cholesterol lodges in the artery wall, where it triggers a harmful sequence of events. Any injury to the inner layer of cells lining the artery (caused by high blood pressure, smoking, or diabetes, for example) speeds this process. White blood cells arrive on the scene and engulf LDL cholesterol in the artery wall. These cells then enlarge and transform into fat-laden foam cells.

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Stage 3 A fibrous cap tops the plaque

As foam cells die, they release soft, fatty gruel that provokes further inflammation. Smooth muscle cells in the artery wall enlarge and multiply, forming a cap over the whole mess and adding to the bulk of the plaque. The bigger the plaque, the more blood flow is restricted.

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Stage 4  The plaque ruptures

Large plaques tend to be covered by thick, fibrous caps that resist breaking apart. Smaller plaques may be too small to block blood flow—and for this reason do not necessarily show up during a cardiac stress test. But they can be just as dangerous, as they are active, dynamic lesions teeming with inflammatory cells. And they sometimes have very thin, underdeveloped caps that rupture easily. About three of every four heart attacks occur because of plaque rupture.

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Stage 5 A clot blocks the artery

Once a plaque ruptures, a protein called tissue factor is released into the bloodstream, where it attracts platelets. The platelets stick to the disrupted plaque, triggering proteins in the blood to start clotting. The result is a thrombus—a clot of red blood cells, platelets, and other material—that completes the blockage and prevents blood from reaching the heart cells downstream. Deprived of blood and oxygen, a portion of the heart muscle dies.

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In addition, coronary artery disease can lead to heart failure (a chronic condition in which a weakened heart causes shortness of breath, fatigue, and fluid accumulation), abnormal heart rhythms (which can lead to a stroke), or cardiac arrest (in which the heart suddenly stops, usually because scarring of the heart muscle or insufficient blood flow produces an abrupt electrical disturbance). The good news is, coronary artery disease can be treated. To learn how, read on.

Normally, people think of risk factors as the conditions and behaviors that predispose a person to an illness in the first place. But even after you’ve been diagnosed with coronary artery disease, it’s important to pay attention to the risk factors for heart disease, because these are the very same things that cause the disease to worsen, if left unchecked. By addressing these issues now, you can slow the progression of coronary artery disease. In some cases, you can even partially reverse it.

Although you can’t change some of these risk factors (namely, your age, gender, and genetic profile), you can control many others by making positive lifestyle choices like exercising regularly, avoiding tobacco, losing weight if you’re overweight, and eating a healthy diet. All of those habits will also help you manage other health problems, such as diabetes and high blood pressure. (For more information and tips on how to make these changes, see “Lifestyle habits that help your heart”.)

Fast fact:

Only 56% of women recognize that heart disease is the No. 1 killer of women in the United States, according to a survey from the American Heart Association. Heart disease claims the lives of more than 401,000 women a year, compared with about 271,000 deaths from all types of cancer combined.


What you can’t control

Some risk factors for coronary artery disease are unavoidable. But it’s good to be aware of them and to remember that you can offset some of these risks by addressing the factors that are within your control.


Age

Heart disease becomes more prevalent with age in both men and women. More than four in five people who die from heart attacks are over age 65. In men, risk begins to mount beyond age 45, whereas women’s risk rises after age 55.


Gender

Men often develop heart disease at younger ages than women—the average age for a first heart attack in men is 65; for women, it is 70. As a result, many people tend to think of heart disease as a man’s ailment. In fact, heart disease is the leading killer of both men and women in the United States. And contrary to public perception, more women actually die of heart disease than men. This has been true every year since 1984 (see Figure 3). What’s more, women are almost twice as likely as men to have a second heart attack within six years of the first and more likely to die in the hospital after coronary artery bypass surgery or angioplasty. In short, there are real gender-related risks—but they’re not necessarily what you expect.

Figure 3: Deaths from heart disease: Men vs. women

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Source: National Center for Health Statistics.

What’s behind these disparities? One possible explanation may be that, because women tend to develop heart disease at a later age, they’re frailer and also more likely to have other illnesses such as diabetes, which can hinder their recovery. Another problem is anatomy: women’s hearts tend to be smaller than men’s, making it more difficult for surgeons to stitch arteries together during surgery or keep them open after angioplasty. A condition called coronary microvascular disease could be another reason (see “What is coronary microvascular disease?”).

What is coronary microvascular disease?

Unlike typical coronary artery disease, which affects the heart’s largest arteries, microvascular disease affects the heart’s smallest arteries. Instead of growing inside the artery, plaque limits blood flow by growing evenly around the artery or bulging outward. In addition, these tiny arteries can constrict and tighten, preventing adequate blood flow. Standard tests such as a coronary angiogram don’t always detect microvascular disease, which is more likely to occur in women than men.

Some research also suggests that women with heart problems may not be diagnosed as early or treated as aggressively as men. For instance, women with heart attack symptoms are less likely than men to be admitted to the intensive care or coronary care unit and to get electrocardiograms, clot-busting drugs, or cardiac catheterization. After leaving the hospital, they are less likely to be directed to a cardiac rehabilitation program (or to finish one), or to get counseling about nutrition, exercise, and weight loss.

Hormones were once considered a possible explanation for the gender differences seen in heart disease. But teasing out the effects of testosterone and estrogen and their relationship to heart disease risk has proved complicated. In women, estrogen raises HDL cholesterol and lowers LDL cholesterol. But when estrogen declines at menopause, typically around age 50, so do its protective effects, causing a sharp increase in the risk for heart disease. Women who have gone through menopause are two to three times as likely to develop heart disease as women the same age who are still menstruating. Yet, as two major studies showed, not only does hormone therapy fail to prevent heart disease, it may actually increase heart disease risk in some cases—particularly if a woman starts taking hormones 10 years or more after she reaches menopause.

Similarly, men with low testosterone levels appear to have a higher risk of heart disease, type 2 diabetes, and other long-term conditions. But there’s no evidence that boosting testosterone levels (via injections, gels, or lozenges of the hormone) can lessen that risk. What’s more, athletes who abuse testosterone and other male hormones have a clearly higher risk for high blood pressure, heart attack, and stroke.


Family history, race, and ethnicity

Coronary artery disease runs in families, and certain racial and ethnic groups are more at risk than others. As with most diseases, a combination of genes and environment is involved. Genetics can underlie risk factors such as high cholesterol, blood pressure, and blood sugar. Shared environmental and lifestyle characteristics such as smoking, diet, inactivity, or psychological stress clearly play a role as well.

Family history. Many studies have shown that people with a father or brother who developed coronary artery disease before age 55 or a mother or sister stricken before age 65 face a much higher risk than others of developing heart disease themselves. Estimates of the magnitude vary, but this type of family history is clearly on a par with other major risk factors such as high blood pressure and cholesterol.

Many studies are now under way to better understand the genetics of heart disease. The hope is that genetic testing will one day enable doctors to identify people at high risk for heart problems and perhaps help them avoid those problems with preventive treatment. In the meantime, if you have a family history of heart disease, it’s vital to address risk factors such as high blood pressure and elevated cholesterol and adopt a heart-healthy lifestyle as soon as possible.

Race and ethnicity. Blacks are more likely to develop heart disease and to die from it than whites, Latinos, and Asian Americans. In fact, when adjusted for age, death rates from heart disease are 30% higher in black men than in white men, and 40% higher in black women than in white women. One reason behind these trends may be the prevalance of high blood pressure among blacks. Other possible contributing factors include education and economic differences, both of which can affect access to appropriate medical care, and race-related stressors such as discrimination. As a result, despite advances in medical treatments for heart disease, life expectancy remains approximately five years higher in whites than in blacks.


What you can control

A number of major risk factors for heart disease are within your power to change, if you’re willing to alter your lifestyle habits (see “Lifestyle habits that help your heart”). In addition, treating and managing related health conditions, such as diabetes, can also lessen your risk. This section details how poor lifestyle habits and uncontrolled medical problems put you in danger. Understanding the risks may help give you the motivation to make changes.


Smoking

People who smoke are two to three times as likely to die from heart disease as nonsmokers, according to a 2013 study on 50-year trends in smoking in The New England Journal of Medicine. Chemicals in tobacco smoke damage the lining of blood vessels and blood cells, setting the stage for atherosclerosis. And it’s not just yourself you’re hurting. Exhaled smoke and smoke from the lit end of a cigarette also harm the hearts of people nearby. The U.S. Surgeon General has warned that secondhand smoke at home or work increases a nonsmoker’s risk of heart disease by 25% to 30%.

There is no safe level of smoking. In a study of light-to-moderate smokers (one to 14 cigarettes daily), female smokers had nearly double the risk of dying suddenly from heart disease as nonsmokers. For every five years a woman continued to smoke, her risk of sudden death rose by 8%.

People who continue to smoke after being admitted to a hospital for a heart attack or unstable angina are three times as likely to die within a year as people who quit smoking, according to a study in The American Journal of Cardiology.

Air pollution is hard on hearts

Growing evidence finds that smog has damaging effects not just on the lungs, but also on the heart. According to the Environmental Protection Agency, both short-term and long-term exposure to air pollution can make people more likely to die from heart disease. Why? Breathing the tiny particles that pollute air can damage blood vessels, raise blood pressure, and make blood more likely to clot. Try to stay indoors at times when local reports indicate that smog levels are at their worst.


Unhealthy diet

When it comes to heart disease, you are what you eat. A poor diet contributes to elevated cholesterol and triglycerides, high blood pressure, diabetes, and obesity. A number of major studies provide compelling evidence that diet also affects the likelihood of progressing to full-blown coronary artery disease and having a heart attack.

It’s long been known that a diet packed with saturated fat (the kind found in animal products) raises your levels of LDL, or “bad” cholesterol. But recently scientists have learned that refined carbohydrates (think white flour and sugar) are also bad for the heart. The reasons aren’t fully clear, but there are at least two possible explanations: refined carbs increase levels of inflammation, and they also tend to replace other, healthier foods in your diet. These healthier foods can have beneficial effects on blood pressure, cholesterol, the flexibility of blood vessels, and the likelihood of blood to clot.

Just about everyone can benefit from a heart-healthy diet. Be aware, however, that while some foods, such as soy products and cereals, come with labels identifying them as “heart-healthy,” no one food will prevent or reverse heart disease. Instead, decades of research back up the idea that it’s the overall composition of the diet that counts—in particular, eating plenty of vegetables, fruits, whole grains, nuts, and lean protein (see “Eat healthy foods”).


Lack of exercise

Only one in three American adults walks, gardens, golfs, or engages in other forms of physical activity in his or her free time. And the reality is that most people sit much of the day—while commuting to work, on the job, and in front of a television or computer when they come home.

All of that sedentary behavior isn’t healthy for your heart, as a growing number of studies show. In one, researchers studied more than 7,700 men over a 21-year period, tracking how many of their waking hours the men sat (riding in a car or watching television, for instance). Men who spent more than 23 hours a week sitting had a higher risk of dying of heart disease than men who spent less than 11 hours a week being sedentary.

Furthermore, if you’ve already had a heart attack, an exercise-based rehabilitation program can reduce your likelihood of dying from heart disease by one-third. Once you get the okay from your doctor, the sooner you start exercising, the better—even as early as a week after your heart attack. That was the conclusion of an analysis that pooled information from 31 different studies examining more than 1,600 heart attack survivors. Researchers found the greatest gains in heart-pumping ability in those who started exercising a week after their heart attack and who continued for at least three months. (For tips on adding exercise to your daily routine, see “Get active.”)


Overweight or obesity

Because obesity is so closely linked to high blood pressure, unfavorable cholesterol levels, lack of exercise, and diabetes, scientists took a long time to figure out whether obesity itself is a cardiac risk factor. Experts now agree that it is. Excess weight increases your risk for heart disease independent of these other conditions. A study that tracked more than 6,000 middle-aged men for about 15 years found that obese, middle-aged men were about 60% more likely to have a fatal heart attack than non-obese middle-aged men, even after the researchers accounted for the effects of cholesterol, blood pressure, and other risk factors for heart disease. The study underscores the danger of packing on extra pounds.

You probably already know whether you could stand to lose a few (or many) pounds. But it’s a good idea to check your body mass index (BMI), a measurement takes both height and weight into consideration, to see whether your weight is putting you at risk. (See www.health.harvard.edu/bmi for a BMI calculator.) Aim for a BMI of 19 to 24, the range that’s considered normal and poses minimal risk for heart disease and other health problems. A person with a BMI of 25 to 29 is considered overweight (moderate risk), and someone with a value of 30 or over is classed as obese (high risk).

If you’re overweight or obese, it’s worth noting that losing even a modest number of pounds—just 5% to 10% of your total weight—can help lower blood pressure and improve cholesterol levels. (For more on weight loss, see “Eat healthy foods”.)


Diabetes

Many experts suspect that the long-term elevated blood sugar and low-grade inflammation seen in diabetes damage the coronary arteries and speed the process of atherosclerosis. That’s why a person with diabetes has the same high cardiac risk as someone who has already had a heart attack. At least 65% of people with diabetes will die from some type of cardiovascular disease—a death rate that is two to four times that of the general population.

If you have diabetes, do your best to keep your cholesterol levels and blood pressure under control. Aim for an LDL cholesterol level of less than 100 milligrams per deciliter (mg/dL) and a blood pressure of less than 130/80 (ideally, less than 120/80). Also keep your blood sugar levels as close to normal as possible. However, tight blood sugar control doesn’t protect against heart attack as much as it helps to prevent other complications of diabetes, such as eye and kidney disease. Ask your doctor for a specific goal, as the target level depends on the blood test used to assess it.

Yet another link between diabetes and cardiovascular disease should give you pause: diabetes can cause chronic kidney disease, which can increase the risk of cardiovascular disease even more. A larger-than-normal amount of a protein called albumin in the urine—a condition known as microalbuminuria—is an early sign of chronic kidney disease. Make sure your doctor orders a urine test for microalbumin at least once a year. And continue to do your part by controlling your blood sugar and blood pressure. Certain drugs used to treat blood pressure can help curb kidney damage.


High blood pressure

The higher your blood pressure, the greater your risk of suffering a heart attack, heart failure, stroke, or kidney disease. Yet too many people ignore the risk posed by high blood pressure (also known as hypertension). Treating high blood pressure really pays off. Clinical trials have shown that treatment reduces the incidence of stroke by 35% to 40%, of heart attack by 20% to 25%, and of heart failure by more than 50%.

Blood pressure goals. Federal guidelines define normal (meaning “optimal”) blood pressure as anything under 120/80 millimeters of mercury (mm Hg). The category of prehypertension is intended to identify people who might prevent or at least slow the onset of high blood pressure by adopting a healthier lifestyle (see Table 1).

Table 1: Blood pressure guidelines

The guidelines listed in this table are for adults ages 18 and older, based on the average of two or more seated blood pressure (BP) readings on each of two or more office visits.

Category

Systolic BP (mm Hg)

Diastolic BP (mm Hg)

Treatment recommendations

Normal

Less than 120

Less than 80

Lifestyle changes encouraged to maintain health

Prehypertension

120–139

80–89

Lifestyle changes necessary

Drugs for compelling indications *

Stage 1 hypertension

140–159

90–99

Lifestyle changes necessary

Thiazide diuretic for most people

May also consider other blood pressure drugs alone or in combination

Drugs for compelling indications *

Stage 2 hypertension

160 or higher

100 or higher

Lifestyle changes necessary

Two or more blood pressure drugs for most people

Drugs for compelling indications *

* Compelling indications: diabetes, chronic kidney disease, previous heart attack, heart failure, previous stroke, high cardiac risk.

Note: When systolic and diastolic pressures fall into different categories, physicians rate overall blood pressure by the higher category. For example, 150/85 mm Hg is
classified as stage 1 hypertension, not prehypertension.

Source: Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7).

About 60% of American adults have either pre-hypertension or hypertension. And data from the Framingham Heart Study indicate that people who are 55 years old and have normal blood pressure face a 90% chance of developing hypertension as they get older, unless they take preventive steps.

When to be tested. Because blood pressure usually begins gradually increasing between ages 20 and 50, all adults should have their blood pressure checked regularly. Blood pressure checks every two years might suffice for people with normal levels. But people with elevated blood pressure need more frequent measurement—once a year for those with prehypertension, and sometimes even more frequently in people with hypertension.

How low to go. For people with high blood pressure, good control is defined as getting your pressure under 140/90 mm Hg. But people with diabetes or chronic kidney disease should aim for an even lower level, below 130/80 mm Hg. The American Heart Association (AHA) recommends that people with coronary artery disease or other forms of atherosclerosis should also lower their blood pressure below 130/80 mm Hg. However, this advice has been questioned, in light of research showing that blood pressure values below 130/80 did not result in fewer cardiovascular events. And doctors are beginning to rethink the wisdom of strict blood pressure goals in older, frail adults. As blood vessels stiffen with age, slightly higher blood pressure values might be needed to keep plenty of blood flowing to the brain and heart. Blood pressure that is too low can make you more prone to fainting, which raises your risk of injury. So if you’re past age 75, don’t be concerned if your doctor doesn’t think it’s a problem that your blood pressure is a bit higher than normal.

To prevent or treat high blood pressure, the first step is to adopt healthier habits (see “Lifestyle habits that help your heart”). But many people with high blood pressure also need medications to treat the disorder (see “Blood pressure medications”).


Unfavorable blood lipids

Many different forms of lipids, or fats, circulate through your bloodstream, including various forms of cholesterol and triglycerides. About one in five Americans has high total cholesterol, defined as 240 mg/dL or higher. But the chance of having a heart attack drops by 20% to 30% for each 10% drop in your total cholesterol level. The most recent federal guidelines spell out how to set your cholesterol goal based on your category of heart disease risk, as well as what steps to take to achieve your goal (see Table 2).

Table 2: LDL cholesterol treatment goals and recommendations

Use this table to get an overview of your goals and recommendations for treatment, depending on your level of risk for heart disease. (See Table 4, to determine your risk category.)

If your risk category is …

Your LDL cholesterol goal should be …

You should start lifestyle changes if your LDL is …

Consider drug therapy when Your LDL is …

Very high

below 70 mg/dL*

at or above 100 mg/dL

at or above 100 mg/dL (optional: below 100*)

High

below 100
(optional: below 70*)

at or above 100

at or above 100 (optional: below 100*)

Moderately high

below 130 (optional: below 100*)

at or above 130

at or above 130 (optional: 100–129*)

Moderate

below 130

at or above 130

at or above 160

Low

below 160

at or above 160

at or above 190 (optional: 160–189*)

* Optional goal. If treatment brings your lipid levels substantially below the values listed above, you shouldn’t worry about being overtreated unless you’re having adverse side effects from the medication.

Source: National Cholesterol Education Program, National Institutes of Health.

Although total cholesterol levels are important, it’s even more crucial to look at levels of different forms of cholesterol, particularly LDL and HDL. These two cholesterol types work in opposite directions. LDL delivers cholesterol to artery walls; higher levels of it promote artery-clogging atherosclerosis. HDL removes cholesterol from the bloodstream and from artery walls; higher levels of it work to prevent plaque buildup. That is why the guidelines recommend that everyone age 20 or older undergo a fasting lipid profile test (also called a full lipid profile or lipoprotein analysis) every five years. This test measures not only total cholesterol, but also LDL, HDL, and triglyceride levels.

Total cholesterol. This number is the sum of cholesterol carried in all cholesterol-bearing particles in the blood, including HDL, LDL, and very-low-density lipoprotein (VLDL). Although the total cholesterol level closely parallels the LDL level in most people, there are enough exceptions to that rule to make it useful to test separately for LDL, HDL, and triglycerides. Government guidelines advise aiming for a total cholesterol level below 200 mg/dL.

LDL. There is no specific cholesterol level that guarantees you will—or won’t—develop heart disease. However, LDL is clearly the bad guy in terms of raising your cardiac risk, so lowering elevated LDL should be the primary target of therapy. Clinical studies indicate that for every 1% reduction in LDL levels, there is a corresponding 1% drop in the chance of suffering a heart attack, stroke, or related event. The right mix of lifestyle changes and medications can help lower LDL levels by 30% to 40% in many people at risk for heart disease, creating a corresponding drop in the risk for cardiac events.

So how low should you go? If you have had a heart attack or are at very high risk of having one, the answer is probably as low as possible. Your particular LDL target depends on your cardiovascular health and your odds of having a heart attack in the next 10 years. Targets range from below 70 mg/dL for those at very high risk up to 160 mg/dL for people with the least overall risk. (To determine your personal risk, see “Assessing your level of cardiovascular risk”.)

You can lower LDL levels by eating less meat, cheese, eggs, and processed foods, which have higher amounts of unhealthy types of fat; consuming more fruits and vegetables; losing weight if you need to; and exercising regularly (see “Lifestyle habits that help your heart”). If these good habits aren’t enough to help you reach your cholesterol goal, cholesterol-lowering medications are recommended.

HDL. The more HDL in your bloodstream, the lower your chances of having a heart attack. Results from the Framingham Heart Study (a long-running, landmark study of factors contributing to heart disease) suggest that every one-point rise in HDL lowers the risk for heart attack by 2% to 3%. The federal guidelines consider levels of 60 mg/dL or above protective against heart disease, while levels of less than 40 mg/dL are thought to increase your risk. To boost your HDL, your best bets are to lose weight, eat well (paying particular attention to minimizing unhealthy fats and consuming more heart-healthy fats, such as olive oil or canola oil), engage in more physical activity, stop smoking, and drink alcohol in moderation (no more than one drink a day for women and two for men). Certain medications can also help to raise HDL levels (see “Cholesterol medications”).

What is C-reactive protein?

C-reactive protein (CRP) is a protein made by the liver in response to infection, inflammation, or tissue injury anywhere in the body. For years, doctors have measured blood CRP levels to monitor diseases such as pneumonia, rheumatoid arthritis, and lupus. The discovery that inflammation is an integral part of atherosclerosis led researchers to develop a new, more sensitive test to measure CRP, called the high-sensitivity CRP (hsCRP) or cardiac CRP (cCRP) test, which measures blood vessel inflammation.

Studies show that people with the highest CRP levels are about twice as likely to develop coronary artery disease and suffer a heart attack or other cardiac event as people with the lowest levels. As a result, CRP is now used along with other markers (such as cholesterol and blood pressure) to estimate cardiovascular risk. A Harvard study showed that people without a history of heart disease who had average LDL cholesterol levels (less than 130 mg/dL) but elevated CRP (equal to or greater than 2 mg/L) who received a cholesterol-lowering statin medication had a 54% decrease in their risk of heart attacks, a 48% reduction in stroke risk, and a 43% decrease in venous blood clots compared with their counterparts who got a placebo pill.

Standards for using CRP in clinical practice are still evolving. For example, it is not yet clear what CRP target levels should be for healthy men and women of different racial and ethnic groups. For now, risk assessment is based on the following three levels of CRP:

  • below 1 mg/L = low risk

  • 1–3 mg/L = average risk

  • above 3 mg/L = high risk.

The hsCRP test is recommended to ensure that you get the most accurate reading.

If you are already being treated for heart disease or are considered at high risk for cardiovascular disease (greater than 20% in the next 10 years, based on the calculations in Table 4 or an online risk calculator), a CRP test is not necessary. The results won’t change how you and your doctor manage your condition.

If you have a moderate risk of heart attack (10% to 20% in the next 10 years), an hsCRP test might help to more accurately place you in a high- or low-risk category. Studies indicate that people at moderate risk based on the conventional risk factors might move into the high-risk category if they also have elevated CRP. Such people might need more aggressive treatment to prevent a heart attack. In particular, your doctor may recommend a lower LDL goal—under 100 mg/dL rather than under 130 mg/dL.

If your cholesterol levels are fine but you have other risk factors (such as diabetes, high blood pressure, or a family history of heart disease), ask your doctor whether an hsCRP test would help to better assess your risk and decide how to reduce it. Think of the results as a “tiebreaker” to help you decide whether to take medications, if you’re on the fence about doing so.

Ratio of total cholesterol to HDL. Some clinicians use the ratio of total cholesterol to HDL cholesterol to help identify people who need cholesterol-lowering therapy. As a general rule of thumb, the lower the ratio, the better. To determine your ratio, simply divide total cholesterol by HDL cholesterol. Reports from the Framingham Heart Study suggest that for men, a ratio of 5 signifies average heart disease risk; for women, average risk is signified by a ratio of 4.4.

Triglycerides. The main form of stored fat—both in the food we eat and in the body’s adipose (fat) tissue—is triglycerides. In general, triglyceride levels have less impact on heart disease risk than LDL or HDL levels. However, when triglyceride levels are very high, risk for heart disease does increase. Often people with low HDL cholesterol levels also have high triglycerides, and this combination seems an especially important predictor of heart disease risk.

Table 3: Triglyceride levels

Triglyceride level

Triglyceride category

Less than 150 mg/dL

Normal

150–199 mg/dL

Borderline high

200–499 mg/dL

High

500 mg/dL and above

Very high

Source: National Cholesterol Education Program, National Institutes of Health.

Normal fasting triglyceride levels are below 150 mg/dL (see Table 3). High triglyceride levels can result from obesity, physical inactivity, tobacco exposure, alcohol abuse, uncontrolled diabetes, and even certain medications, as well as some genetic disorders. Often, you can lower your triglycerides using the same steps that help bring down LDL cholesterol: choose healthful foods, exercise more often, lose weight, avoid tobacco in all its forms, and, if necessary, take medications.

Because you have already been diagnosed with coronary artery disease, you are considered to be in the high or very high risk category for having a heart attack or stroke, or needing a cardiac procedure such as angioplasty or bypass surgery (see “Risk treatment categories,” below). The same is true for people with diabetes or chronic kidney disease.

In the past, physicians gave people ballpark assessments of their heart attack risk based on their total cholesterol level. Today there are statistics-based tools called risk calculators that predict much better who is most likely to have a heart attack or some other complication of coronary artery disease. Even more importantly, they enable doctors to tailor treatment to an individual’s particular risk profile, with a multipronged strategy of diet, exercise, and medication. Although there is no one-size-fits-all solution, in general, the higher your risk, the more aggressive the treatment you will receive.

Risk treatment categories

The following five categories are used to guide a person’s treatment for coronary artery disease.

Category 1: Very high risk

• cardiovascular disease (a previous heart attack or stroke or episode of unstable angina; stable angina; a heart procedure such as angioplasty or bypass surgery; detection of narrowed or partially blocked arteries in your heart, neck, legs, or elsewhere)

and one or more of the following:

• diabetes or kidney disease

• severe and poorly controlled risk factors (cigarette smoking, uncontrolled high blood pressure, or family history of heart disease)

• multiple risk factors, especially high triglycerides (200 mg/dL or above) and low HDL (below 40 mg/dL).

Category 2: High risk

• a history of heart disease (such as heart attack, stable or unstable angina, or a heart procedure such as angioplasty or bypass surgery)

or

• a heart disease “risk equivalent” (such as diabetes, kidney disease, peripheral artery disease, blocked carotid arteries, or transient ischemic attacks), along with two or more major risk factors (such as smoking, high blood pressure, or family history of heart disease

and

• a 10-year cardiovascular disease risk of more than 20% (see Table 4).

Category 3: Moderately high risk

• two or more major risk factors

and

• a 10-year cardiovascular disease risk of 10% to 20% (see Table 4).

Category 4: Moderate risk

• two or more major risk factors

and

• a 10-year cardiovascular disease risk of less than 10% (see Table 4).

Category 5: Low risk

• one major risk factor or none.

Table 4 contains one risk calculator for estimating your chances of further cardiac problems over the next decade. Researchers with the Framingham Heart Study developed this risk tool. Note that a 3% risk means that three out of 100 people with your risk profile will have a heart attack in the next 10 years, a 10% risk means that 10 out of 100 people with your risk profile will have one in the next 10 years, and so on. This risk calculator also presents risk in a new way; it gives an estimate of your “vascular age”—how old your arteries are, regardless of how old you are.

Alternately, if you prefer to use an online risk calculator, you can find a detailed one in the heart disease section of the website “Your Disease Risk,” at www.yourdiseaserisk.wustl.edu.

Table 4: What’s your 10-year risk of cardiovascular disease (CVD)?

Step One: Calculate your cardiovascular risk. Tally up your total points from the six categories below.

Step Two: Convert points to risk. Find your total points in the left column of the appro­priate gender table below to find your 10-year risk of CVD and your vascular age.

If you’ve got coronary artery disease, your doctor has probably mentioned that it’s important for you to eat a heart-healthy diet, exercise regularly, and give up cigarettes, if you’re a smoker. These measures are so powerful, they should be considered an essential part of your treatment, along with medication. In addition, research has recently highlighted the cardiac benefits of adequate sleep and stress reduction.

Getting on board with these habits takes a fair amount of time and effort, but the rewards are well worth it. The good news is that these factors are all interconnected. Smoke fewer cigarettes and you’ll find that you’re less winded when you exercise. The more you exercise, the easier it will be to shed extra pounds. And losing weight can help lower both high blood pressure and cholesterol, as well as control diabetes.

This special section details how to make these potentially lifesaving changes.


Stop smoking

A variety of tools can double or triple your chances of kicking your smoking habit. The best approach uses medication to quell cravings for nicotine along with some sort of support or counseling to break the patterns that make a smoker reach for a cigarette. In the meantime, a few tips may help:

Know the enemy. List all the hazards of smoking. Then write down why you want to quit. Keep this list where you can refer to it easily.

Make a date. Pick a date to quit and prepare yourself by figuring out how you will deal with cravings. The day before, throw away all cigarettes, ashtrays, and lighters—anything that may tempt you.

Talk with your doctor. Smoking changes the way your body processes some medications, so talk with your doctor about how to manage doses. You may also want to ask about nicotine replacement (available as patches, gum, and inhalers) and bupropion (Wellbutrin, Zyban) to ease cravings. Varenicline (Chantix) is another option. This drug packs a one-two punch: by binding to the same receptors in the brain as nicotine, it can help ease withdrawal symptoms and also make smoking less pleasurable if you do slip up and resume smoking.

Avoid temptation. Until you feel stronger in your resolve, try to avoid social situations that may trigger the desire to smoke.

Find alternatives. Start exercising or take up another healthy, engaging pastime that brings you pleasure. A substitute activity that takes the place of smoking can help you beat the habit.

Keep trying. If you don’t succeed on your first try, try again. It often takes several attempts to quit smoking completely.


Get active

What kind of exercise is best, and how much should you do? After a “breaking in” period, aim for 30 minutes or more of moderate activity per day as a good initial goal. (Examples of moderate activity include bicycle riding at a leisurely pace, gardening, golf, housework, mowing the lawn, raking leaves, and walking at 3 to 4 mph.) Aerobic exercise, which uses large muscle groups in a rhythmic, repetitive fashion for prolonged periods of time, is the best type of exercise for the heart. But flexibility exercises (those that stretch muscles) and resistance exercises (which strengthen them) are also good. Try the following steps to ease into a fitness routine:

Get started. After a heart attack or procedure, your first exercise should take place in a medical setting during the first few weeks of your recovery. Your heart rate will be monitored to make sure you don’t develop any dangerous heart rhythms. If you don’t attend a formal cardiac rehabilitation program, you should have a pre-exercise stress test, which can help set the guidelines for your exercise prescription.

If you aren’t doing much physically, even mild exercise a few times a week will cut your heart disease risk in half. Just walking at a reasonable pace can make a big difference in the health of your blood vessels. Raising your heart rate and dilating arteries a bit can help to lower your blood pressure and prevent atherosclerosis. Start with 20- to 30-minute walks three days a week, then build up to 30 minutes or more nearly every day. Or try three 10-minute walks every day, which is just as effective. If you feel chest pressure, lightheadedness, or marked shortness of breath, see your doctor right away.

Pump up the volume. If you can do mild or moderate physical activity daily, start doing short bursts of more intense activity. You can walk five miles every day at the same slow clip, and you will burn plenty of calories. But short bursts of intense activity—30 to 60 seconds of really pushing yourself—can help take the health of your blood vessels to a new level. If you walk for exercise, for instance, increase your pace, try a slow jog, or try walking in a pool (the water provides resistance, making you work harder). This type of moderate physical stress on the arteries helps to keep them younger.


Eat healthy foods

Advice on healthy eating—especially for people with heart disease—has evolved over the past decade. Instead of focusing on individual nutrients or specific vitamins, the new emphasis is a food-based approach. This strategy makes sense for a lot of reasons. For one thing, it’s less complicated. Who wants to tally up how many grams of fat or fiber they’re eating each day? Also, we don’t eat nutrients in isolation. When you eat “protein”—say, a spoonful of peanut butter—you also get some fat, vitamins, carbohydrates, and fiber. This may also explain why taking individual vitamins or other supplements has not proved helpful (see “What about vitamins and other supplements?”). And the once-popular advice for heart patients to follow a low-fat diet has fallen by the wayside. That’s because people who tried cutting down on fat usually stopped eating healthy unsaturated fats along with unhealthy saturated fats, and also turned to foods rich in rapidly digested carbohydrates, which aren’t good for the heart.

What about vitamins and other supplements?

Over the past few decades, various vitamins and nutritional supplements have been touted for their alleged ability to stave off heart disease. But while numerous observational studies have shown links between higher vitamin intakes and heart health, the more rigorous research that compares people who take specific vitamins with those who take placebos has come up short. In fact, the American Heart Association guidelines specifically state that supplements of vitamin C, vitamin E, beta carotene, and three B vitamins (folic acid, B6, and B12) should not be taken to prevent heart disease. Not only do they not help, there’s even some suggestion that taking vitamin E supplements may slightly raise the risk of heart failure and hemorrhagic (bleeding) strokes.

Calcium supplements have also come under scrutiny following a report suggesting that men who took more than 1,000 milligrams of supplemental calcium daily over a 12-year period were 20% more likely to succumb to heart disease than those who didn’t take the pills.

And while some studies have found that popping fish oil capsules lowers the chance of having a heart attack or related problem, others failed to find such a benefit, including a 2013 report involving about 12,500 people with high blood pressure and other risk factors for heart disease.

The bottom line? Get your nutrients from foods, not pills.

Nutrition experts summarized the current advice on a food-based approach to a heart-healthy diet in the journal Circulation (see Table 5). Instead of focusing on what you shouldn’t eat (foods laden with fat, sugar, or salt), they advised, concentrate more on what’s missing from your diet—fruits, vegetables, whole grains, and healthy fats. Only about a quarter of Americans eat three or more vegetables a day, and about a third eat two or more fruits, which means most people get woefully low amounts of these nutrient-dense foods.

Table 5: Foods to enjoy and to avoid in a heart-healthy diet

 

Goal

One serving equals…

Examples

E

A

T

M

O

R

E

Vegetables

4 to 5 servings per day

1 cup of raw leafy vegetables; ½ cup of cut-up raw vegetables, cooked vegetables, or 100% vegetable juice

Spinach, kale, and other green leafy plants; broccoli, peas, carrots, onions, peppers. Don’t include potatoes, corn, and other starchy vegetables in this category.

Fruits

4 to 5 servings per day

1 medium-sized fruit; ½ cup of fresh, frozen, or unsweetened canned fruit; ½ cup of dried fruit; ½ cup of 100% juice

Blueberries, strawberries, apple, grapes, kiwi, grapefruit, avocado, mango

Whole grains

3 or more servings
per day, in place of
refined grains

1 slice of whole-grain bread; 1 cup of high-fiber, whole-grain cereal; ½ cup of cooked whole-grain rice, pasta, or cereal

Brown rice, whole-grain bread,
oats, bulgur, whole-wheat couscous, barley

Vegetable oils

2 to 6 servings per day

1 teaspoon oil, 1 tablespoon vegetable spread

Canola oil, olive oil, safflower oil, peanut oil, soybean oil; “tub” spreads made with vegetable oils

Dairy products

2 to 3 servings per day

1 cup of milk or yogurt; 1 ounce of cheese or sour cream

Reduced fat or nonfat milk or yogurt, buttermilk, cottage cheese

Nuts and seeds

4 to 5 servings per week

1.75 ounces (the proverbial “handful”)

Almonds, walnuts, peanuts, hazelnuts, cashews, pecans, Brazil nuts, sunflower seeds, sesame seeds

Fish and shellfish

2 or more servings
per week

3.5 ounces (about the size of a deck of cards)

Salmon, tuna, mackerel, trout, herring, and sardines

 

E

A

T

L

E

S

S

Sugar-sweetened beverages, sweets, grain-based desserts, and
bakery foods

No more than 5 servings per week

8 ounces (1 cup) of beverage; 1 small sweet, pastry, or dessert

Sugar-sweetened soda, fruit drinks, sports drinks; candy bars, packaged sweets; cookies, donuts, pie, cake, ice cream

Processed meat

No more than 2 servings per week

1.75 ounces

Bacon, sausage, hot dogs, pepperoni, salami, processed deli meats

Any food containing or made with partially hydrogenated vegetable oil

Don’t eat

 

Stick margarine, commercially prepared baked foods (cookies, pies, donuts, etc.), snack foods, and deep-fried foods

Source: Adapted from Circulation, 2011.

The foods noted in this table jibe well with eating patterns shown to be good for your heart—most notably, the Mediterranean diet. Early evidence for the health benefits of a Mediterranean diet dates back to the 1970s with the publication of the Seven Countries study, which showed the lowest heart disease rates in Greek islanders and southern Italians. Their traditional diets featured

  • high amounts of olive oil, fruits, vegetables, and whole grains

  • moderate amounts of fish and poultry (and wine, drunk with meals)

  • small amounts of cheese, yogurt, red meat, processed meat, and sweets.

Since then, many studies have shown a link between this eating style and fewer heart attacks and strokes. The strongest proof to date comes from the first major clinical trial of the diet, published in 2013 in The New England Journal of Medicine. Researchers randomly assigned nearly 7,500 people, all at risk for heart disease, to three different diets. Two were Mediterranean-style diets: one with an extra quarter-cup of olive oil and the other with an extra handful of nuts per day. The third group ate a standard low-fat control diet. After nearly five years, researchers stopped the study early because the findings were so striking. People who followed the two Mediterranean plans were 30% less likely to have a heart attack or stroke, or to die from cardiovascular disease.

Mediterranean diet: Good for weight loss, too

Even though the Mediterranean diet is rich in fat, it doesn’t make you fat. In fact, in a two-year study that compared a low-fat diet, a low-carb diet, and a Mediterranean-style diet, people lost the most weight on the low-carb and Mediterranean diets (an average of about 10 and 9 pounds, respectively) versus about 6 pounds in the low-fat group. Four years later, about two-thirds of the participants said they’d stuck with their diets, although most had regained some weight—especially those in the low-carb diet group. At the six-year mark, the low-fat group had lost just over a pound and the low-carb group just under 4 pounds. But the Mediterranean group had almost held steady, with an average weight loss of nearly 8 pounds.

These findings uphold earlier research showing that sticking to a low-fat or low-carb diet over the long haul can be hard. If you need to lose weight, a Mediterranean-style diet is an excellent choice.


Sleep soundly

Two sleep-related problems that plague many people—sleep deprivation and sleep apnea—have been linked to a higher risk of heart disease.

Sleep deprivation. Most people need between seven and nine hours of sleep per night, but one in five Americans sleeps less than six hours per night—a trend that can have serious personal and public health consequences. Insufficient sleep can make you too tired to work efficiently, to exercise, or to eat healthfully. Over time, sleep deprivation increases the risk for a number of chronic health problems, including heart disease.

A number of studies have linked short-term sleep deprivation with several well-known risk factors for heart disease, including higher cholesterol levels, higher triglyceride levels, and higher blood pressure. One such report, published in the journal Sleep, included more than 98,000 Japanese men and women ages 40 to 79 who were followed for just over 14 years. Compared with women who snoozed for seven hours, women who got no more than four hours of shut-eye were twice as likely to die from heart disease, the researchers found. (See “Tips for a better night’s sleep”, for advice on good sleep habits.)

Tips for a better night’s sleep

  • Go to bed and wake up at the same time every day, even on weekends.

  • Use the bed only for sleeping or sex.

  • Forgo naps, especially close to bedtime.

  • Avoid caffeine-containing beverages (coffee, many teas, chocolate, and cola drinks) after 2 p.m., or noon if you’re caffeine-sensitive.

  • Limit the time you spend in bed. If you don’t fall asleep within 20 to 30 minutes or if you wake up and can’t fall back to sleep within that amount of time, get out of bed and do something relaxing until you feel sleepy again.

  • Avoid eating foods that contribute to heartburn.

  • Don’t drink alcohol for at least two hours before bedtime.

  • Limit fluids before bedtime to minimize nighttime trips to the bathroom.

  • Stop smoking, or at least do not smoke for one to two hours before turning in for the night.

  • Exercise regularly (but not within two hours of bedtime).

  • Keep the bedroom cool, dark, and as quiet as possible.

  • Replace a worn-out or uncomfortable mattress.

  • Take a hot bath before bedtime.

  • Use relaxation techniques before bedtime.

Sleep apnea. A common cause of loud, disruptive snoring, sleep apnea makes people temporarily stop breathing many times during the night. In those with the most common form, obstructive sleep apnea, soft tissue in the upper part of the mouth or back of the throat completely blocks the airway. The resulting drop in oxygen prompts the brain to send a “Breathe now!” signal that briefly awakens the sleeper and makes him or her gasp for air. That signal also jolts the same stress hormone and nerve pathways that are stimulated when you are angry or frightened (see Figure 4). As a result, the heart beats faster and blood pressure rises—along with other factors that drive up heart disease risk, such as inflammation and a propensity for blood clot formation. Daytime drowsiness often occurs with sleep apnea, which affects one in 10 people ages 65 and older. Up to 83% of people with heart disease also have sleep apnea, according to some estimates.

Research documents the dangers of sleep apnea: in one study, people with severe sleep apnea were three times more likely to have died of cardiovascular disease during 18 years of follow-up than those without apnea. When researchers excluded those who used a breathing machine (a common apnea treatment), the risk jumped to more than five times higher. Apnea spells can trigger arrhythmias (irregular heartbeats), and the condition also increases the risk of stroke and heart failure. Studies are now under way to see if treating sleep apnea with specialized breathing machines can help prevent heart disease deaths.

Ask your doctor if you should have a sleep study—especially if your bed partner complains about your snoring or if you have sleepy spells during the day.


Mind your stress (and negative emotions)

The links between the heart and the mind are harder to measure than those between the heart and the waistline. But a growing body of evidence suggests that psychological factors are—literally—heartfelt, and can contribute to cardiac risk. Stress from all sorts of challenging situations and events plays a significant role in cardiovascular symptoms and outcome, particularly heart attack risk. The same is true for depression, anxiety, anger, and hostility, as well as for social isolation. Acting alone, each of these factors heightens your chances of developing heart problems. But emotional issues are often intertwined: people who have one commonly have another. For example, psychological stress often leads to anxiety, depression can lead to social isolation, and so on. When combined, their influence is compounded.

In some cases, you can make changes to ease your burdens—by changing jobs or relationships, for example. But some of the stress in our lives is simply impossible to avoid, and a moderate amount of stress can act as a positive, motivating force. The question is this: does reducing stress, or changing how you respond to it, actually lower your cardiac risk and the likelihood of having a heart attack? The answer isn’t entirely clear, although some preliminary results suggest yes (see “Relaxation and your health”). The uncertainty reflects the challenge of doing research into psychological stress, which is so often accompanied by behaviors that are risky in their own right, such as smoking and overeating. It also reflects the challenge of persuading people to make changes in the way they think and behave.


The stress response

Your body reacts to life-threatening stress (“The house is on fire!”) with a “fight-or-flight” response. The brain triggers a cascade of chemicals and hormones that speed the heart rate, quicken breathing, increase blood pressure, and boost the amount of energy (sugar) supplied to muscles. All of these changes enable your body to respond to an impending threat. Unfortunately, the body does a poor job of discriminating between grave, imminent dangers and less momentous, ongoing sources of stress. When the fight-or-flight response is chronically in the “on” position, the body suffers.

The release of stress hormones also activates the blood’s clotting system. And long-term mental stress appears to stimulate the body’s production of harmful LDL and triglycerides, interfere with blood pressure regulation, and activate molecules that fuel inflammation (see Figure 4).

Figure 4: The stress response

image

The hypothalamus, pituitary gland, and adrenal glands make up the HPA axis, which plays a pivotal role in triggering the stress response. By releasing certain chemicals, such as adrenocorticotropic hormone (ACTH) and cortisol, the HPA axis rouses the body for action when it’s faced with a stressor. As the illustration reveals, the effect of this release of hormones is widespread. Senses become sharper, muscles tighten, the heart beats faster, blood pressure rises, and breathing quickens. All of this prepares you to fight or flee in the face of danger.


Stressors that harm the heart

Particular events, such as the death of a spouse or being fired from a job, are extremely stressful. Yet research indicates that less dramatic but more constant types of stress may also harm the heart. In a major study in The Lancet that involved over 24,000 participants from 52 countries, roughly 11,000 people who had just had a first heart attack were asked, as they left the hospital, about various forms of stress they had experienced in the preceding 12 months. The questions probed reactions to job and home stress, financial problems, and major life events. Members of a control group, who were matched to the heart attack survivors for age and gender but had no history of heart disease, underwent similar assessments. Despite variations in the prevalence of stress across countries and racial or ethnic groups, increased stress levels conferred a greater risk for heart attack than did high blood pressure, fat accumulated around the waist, diabetes, and several other risk factors.

Many other studies have also documented that various forms of stress can take a toll on the heart:

Workplace stress. Women whose work is highly stressful have a 40% increased risk of heart disease (including heart attacks and the need for coronary artery surgery) compared with their less-stressed colleagues. These findings come from the Women’s Health Study (WHS), which included more than 17,000 female health professionals. For the study, researchers defined job strain as a combination of demand (the amount, pace, and difficulty of the work) and control (the ability to make work-related decisions or be creative at work).

Earlier studies found similar trends among men: one documented twice the risk of newly diagnosed heart disease among men who felt the rewards they received at work weren’t compatible with their effort. Finally, working overtime hours seems to overtax the heart, as evidenced by a study that found a nearly 70% higher risk of heart disease among people who worked an average of 11 hours per weekday, compared with those who worked normal working hours (seven to eight hours per day). The study, which followed nearly 7,100 people (none of whom had heart disease at the outset) for just over 12 years, was published in the journal Annals of Internal Medicine.

Financial stress. Heart attacks rise when the stock market crashes, according to a report in The American Journal of Cardiology. Researchers at Duke University reviewed medical records for 11,590 people who had undergone testing for heart disease during a three-year period, and then compared monthly heart attack rates with stock market levels. Heart attacks increased steadily during one eight-month period—September 2008 to March 2009—that was particularly bad for the stock market (see Figure 5).

Figure 5: Heart attacks rise as stocks crash

image

Heart attacks increased steadily during one eight-month period that was particularly bad for the stock market.

Source: The American Journal of Cardiology, 2010.

Caregiver stress. Women who cared for a disabled spouse for at least nine hours a week were significantly more at risk of having a heart attack or dying from heart disease compared with women who had no caregiving duties, according to findings from the Nurses’ Health Study. This large study followed more than 54,000 female nurses over a four-year period.

Disaster-related stress. Following the terrorist attacks of Sept. 11, 2001, researchers asked 2,700 American adults to complete an online survey of physical and mental health. People who had high levels of stress immediately after the attacks were nearly twice as likely to develop high blood pressure and more than three times as likely to develop heart problems during the following two years compared with those who had low stress levels.

Grief. For some people, the emotional and psychological impact of grief can trigger sudden, intense chest pain, even in people without heart disease. Known as “broken heart syndrome,” the pain feels like a heart attack, but there’s no evidence of a blocked artery or dead heart tissue. Instead, a long-lasting spasm of the artery blocks blood flow, causing the bottom of the heart to balloon out and preventing it from pumping properly. This condition is also known as stress cardiomyopathy or takotsubo cardiomyopathy (tako tsubo is Japanese for octopus trap, which is said to resemble the potlike shape of the afflicted heart).

But grief can also trigger a true heart attack, as documented in a study in Circulation, which found that the chance of having a heart attack is 21 times higher than normal during the first 24 hours following the death of a loved one. Researchers also found that the risk of dying from heart disease in the months after a loved one’s passing rose by 20% to 53%, with the higher increase seen in people with existing heart disease or risk factors for it.

Depression and heart disease

The relationship between depression and heart disease is a two-way street.
Not only does depression appear to promote heart disease, but it can also result from a heart attack. Studies suggest that people who are depressed are about twice as likely to develop coronary artery disease, and that people who already have heart disease are three times as likely to be depressed as other people. For as many as one in five people, depression follows a heart attack. Finally, depression is an independent risk factor for a subsequent heart attack in people who’ve already had one. This may be in part because people who are depressed are less likely to take proper care of themselves—they might continue to smoke, fail to take their medications regularly, or not exercise enough.

Whether you’ve had a heart attack or not, if you feel depressed, tell your doctor. Depression can be treated successfully with antidepressants, psychotherapy, or both. Treating depression can make you feel better and decrease your heart attack risk.


Stress-easing strategies

It’s nearly impossible to avoid all sources of stress in your life. While you can’t change the world around you, you can try to change your reactions and to manage your stress. Try the following to minimize your stress level:

  • Get enough sleep. Lack of sound sleep can affect your mood, mental alertness, energy level, and physical health.

  • Exercise. Physical activity alleviates stress and reduces your risk of becoming depressed.

  • Learn relaxation techniques. Meditation, progressive muscle relaxation, guided imagery, deep breathing exercises, and yoga are mainstays of stress relief. Your local hospital or community center may offer meditation or yoga classes, or you can learn about these techniques from books or videos.

  • Learn time-management skills. These skills can help you juggle work and family demands.

  • Confront stressful situations head-on. Don’t let stressful situations fester. Hold family problem-solving sessions and use negotiation skills at work.

  • Nurture yourself. Treat yourself to a massage. Truly savor an experience: eat slowly, focusing on each bite of that orange, or soak up the warm rays of the sun or the scent of blooming flowers during a walk outdoors. Take a nap. Enjoy the sounds of music you find calming.

  • Cultivate friendships. Having a core group of friends that you can do relaxing activities with and talk to can be extremely helpful in blowing off steam. Remember that friends are the family that you get to choose!

  • Talk to your doctor. Discuss with your doctor why you think that you might be stressed or anxious. Your doctor can give you strategic tips to help you or refer you to a specialist. If stress and anxiety persist, ask your doctor whether anti-anxiety medications could be helpful.


Relaxation and your health

A modest but encouraging body of work shows some benefits to managing stress and anger. One study found that elderly people with hard-to-treat high blood pressure who underwent relaxation training were more likely to be able to effectively control their blood pressure to the point where they could eliminate their blood pressure medications.

If anger is an issue for you, an anger-management program might help. An analysis of 50 studies that included almost 2,000 volunteers found that such programs help people tone down their anger, respond to threatening situations less aggressively, and use positive behaviors such as relaxation techniques or better communication skills. Other studies have demonstrated that improvements like these translate into lower blood pressure and better blood flow to the heart during exercise and stress. It’s not yet known, however, whether anger management can reduce the likelihood of heart attacks, strokes, and other cardiac events.

An evaluation by the Centers for Medicare and Medicaid Services examined two programs aimed at improving cardiovascular health through lifestyle modifications, including stress management, exercise, and nutrition counseling. The study, which ran from 1999 through 2007 and involved 589 patients who already had heart disease, evaluated two nationally recognized programs: one from the Benson-Henry Institute for Mind Body Medicine and one developed by Dr. Dean Ornish.

Both programs had a beneficial effect on cardiac risk factors; for example, participants lost weight, reduced their blood pressure levels, improved cholesterol levels, and reported greater psychological well-being. Participants in both programs also appeared to have better cardiac function. Moreover, those in the Benson-Henry program had lower death rates and were less likely to be hospitalized for heart problems, compared with controls. The study concluded that these kinds of intensive lifestyle modification programs are clinically effective. While this study is good news for those with heart disease, more studies are needed to confirm these results.

Most people with coronary artery disease will undergo testing periodically to evaluate the severity of their condition and to assess whether it is changing. Your doctor will begin with a detailed medical history and physical exam and an electrocardiogram (ECG). The extent of any additional testing you receive will depend on your condition and your doctor’s level of concern. If you have mild, stable, or atypical symptoms (for instance, fleeting episodes of stabbing pain), an experienced clinician might not go any further. On the other hand, if your symptoms are threatening (for example, a squeezing sensation in your chest, with breathlessness when walking more than a few yards and an abnormal ECG), he or she might skip the preliminaries and go straight to an angiogram. In practice, most people fall between these two extremes, and they often benefit from a stepwise approach that begins with easy tests, followed by more sophisticated tests as needed.


Your medical history

When taking your medical history, the doctor should ask about such things as smoking, diet, and exercise; whether your parents or other family members have had heart problems; and whether you have a history of other medical problems, such as high blood pressure, high cholesterol levels, or diabetes. The clinician will also likely ask about chest pain and palpitations.


Chest pain

The most common symptom of heart disease is angina, or pain in the chest brought on by exertion or stress. The pain is often described as a feeling of pressure, heaviness, or tightness. Some people complain of a burning or aching sensation. The discomfort often spreads to the shoulders, arms, neck, or jaw, and is often accompanied by shortness of breath or sweating. Pain that is very short-lived or is limited to a small area (a couple of inches) is probably not from the heart.

Angina often occurs in response to physical or emotional stressors. Angina that lasts just a few minutes and goes away quickly when you rest or take medication is considered stable angina. A more serious form, unstable angina, builds in intensity, lasts several minutes to hours, and doesn’t subside with rest.

Why it happens: Angina occurs when plaque in the coronary arteries partially blocks blood flow and the heart muscle isn’t getting enough oxygen and nutrients (see “Common angina triggers”).

Common angina triggers

  • Walking briskly outside on a cold, windy, or humid day

  • Hurrying with a heavy load

  • Exerting yourself after a heavy meal

  • Working under a deadline

  • Speaking in public

  • Engaging in sexual activity

  • Being worried, tense, or angry

How it’s treated: Stable angina is commonly treated with nitroglycerin, a drug that widens blood vessels. Your doctor will probably also prescribe other drugs used to treat heart disease (see “Medications for heart disease”). But unstable angina demands urgent medical care. If the blockage in your coronary arteries is severe, you may need angioplasty.

Other causes of chest pain that may mimic angina

The heart isn’t the only organ in the chest, and other medical problems can cause chest discomfort, including these:

  • Acid reflux or heartburn. When acid from the stomach flows up into the esophagus, it can cause a burning sensation in the chest that’s often mistaken for angina or a heart attack.

  • Lung conditions. Pneumonia or blood clots in the vessels supplying the lungs tend to cause shortness of breath and sharp pains that intensify with a deep breath.

  • Pericarditis. Inflammation of the tissues around the heart (pericarditis) can cause a sharp pain that often worsens when you lie down.

  • Costochondritis. This condition, caused by inflammation in the chest wall between the ribs and the breastbone, can also trigger pain that’s often mistaken for a heart attack. The stabbing, aching pain may be caused by trauma or an overuse injury, or it may accompany arthritis.

  • Esophageal spasm. This refers to the narrowing and opening of the esophagus, the muscular tube between the mouth and the stomach. Like angina, this pain is also relieved by nitroglycerin. However, only your doctor can conclusively make this diagnosis.

  • Anxiety or panic attack. These attacks—which can occur out of the blue or in response to a stressful event—can cause symptoms very similar to a heart attack, including shortness of breath, palpitations, dizziness, and chest pain. The key difference is that the chest pain is usually fleeting, lasting only a moment or two.


Palpitations

Often described as feeling like the heart is skipping, racing, or fluttering, palpitations are not necessarily a sign of heart disease. Most people experience them at least occasionally. But they may be a symptom of a more serious heart condition, such as an irregular heartbeat (arrhythmia).

Why they happen: Common causes of palpitations include stress or anxiety, strenuous exercise, fever, hormonal changes that occur with menstruation or menopause, or certain stimulant-type drugs, including caffeine, nicotine, weight-loss drugs, or pseudoephedrine (found in some over-the-counter cold and cough medications).

How they’re treated: If palpitations occur in response to a known trigger, try to avoid it. Your doctor may ask you to check your resting pulse regularly. To do so, place your forefinger on your wrist near the base of your thumb to feel the pulse of the radial artery as it supplies blood to the hand. Count the number of pulses during 15 seconds and multiply by four. Most people have heart rates of 60 to 80 beats per minute. But a resting heart rate of 100 or more beats per minute may mean the heart is working extra hard because of some underlying problem. If your heartbeat is irregular (for example, you experience a series of rapid heartbeats that start and stop suddenly), your doctor will probably order an electrocardiogram.


Physical examination

During a routine examination, your doctor will check your blood pressure, pulse, and breathing rate. He or she will also listen to your chest for extra sounds called gallops that may result from damage to or abnormal function of the heart. Gallops are abnormal, soft, thudding noises that the heart makes when it fills with blood. These sounds are not always a sign of coronary artery disease, but they indicate a stiffness of the heart’s main pumping chamber. Gallops are extremely common among older people, particularly if they have high blood pressure. Although gallops are usually nothing to worry about, if you have them, get checked periodically by your doctor for signs of heart trouble.

Your doctor will also listen for a heart murmur, a sound caused by increased or turbulent flow of blood through heart chambers or valves. In some cases, inadequate blood flow due to heart disease deprives the muscles controlling the heart’s mitral valve of needed oxygen, causing a murmur. The mitral valve may also have problems closing correctly if the heart has enlarged because of damage from a heart attack or other medical problem. If the valve fails to close completely during each contraction, blood can be squeezed backward through the valve—a syndrome called mitral regurgitation. Unless the amount of mitral regurgitation is very minor or very pronounced, it will produce a murmur that can be detected with a stethoscope. Other valves in your heart—the aortic, tricuspid, and pulmonary valves—can also malfunction, causing murmurs. Valvular murmurs can result from regurgitation (a leaky valve) or stenosis (a tight valve, usually due to calcium or infection).

Your doctor may also check the pulse in your feet, which may be weakened if there is severe atherosclerosis in the major arteries feeding the legs, a condition known as peripheral artery disease. Sometimes, by looking into your eye with an ophthalmoscope, your doctor can see abnormalities in the small vessels of the retina. If atherosclerosis exists in these vessels, there’s an above-average chance that you also have coronary artery disease. A ring around the iris of your eye or fat-filled nodules just under your skin, particularly on your elbows, hands, and heels, are symptoms of high blood cholesterol levels.

Finally, your doctor will most likely order a blood test to measure your cholesterol and triglyceride levels. A urine microalbumin test and a blood chemistry test can detect diabetes or kidney disease, which are sometimes linked to atherosclerosis.


Electrocardiogram

The single most widely used test for detecting heart problems is the electrocardiogram, which is abbreviated as ECG (or EKG, from the German spelling of electrocardiogram). The ECG provides a picture of the electrical activity that regulates the heart’s cycle of contraction and relaxation (see Figure 6). Every person with suspected or diagnosed coronary artery disease should have an ECG as part of an initial evaluation. This test is likely to be repeated periodically to detect whether a heart attack occurred between examinations.

Figure 6: Electrical waves of the heart

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An ECG produces a diagram, called a tracing, that corresponds with each phase of a heartbeat.

If you have been diagnosed with coronary artery disease, have had an angioplasty or bypass surgery, or have experienced a heart attack or stroke, you should probably have the test yearly, even if you’re feeling fine. Also, because there are wide ranges of what’s considered a “normal” ECG, it’s helpful to have a baseline ECG to compare against future tests, to spot any abnormal changes.

The ECG gives a reading, or tracing, of the electrical activity that occurs with each heartbeat. This simple, painless test reveals a lot about your heart. By evaluating the tracings of your heart’s electrical activity, doctors can spot an irregular heartbeat (an arrhythmia), find out whether your heart is enlarged, or even detect the telltale signs of damage from an old heart attack. The ECG is crucial for evaluating chest pain. ECG abnormalities are often enough to enable emergency department physicians to diagnose a heart attack in progress.

In the standard technique, you lie down as the technician applies four electrodes, or leads, to your skin—one on each arm and one on each leg—with a special paste or adhesive pads. These limb leads permit the recording of cardiac electrical activity from different angles. Six additional electrodes are usually placed across your chest to detect activity at the front and left side of your heart. Sometimes, people who have suspected heart rhythm abnormalities need to wear a Holter monitor or an event recorder, which are, in essence, portable electrocardiogram devices (see “Holter monitoring”).

Holter monitoring

A Holter monitor is a portable ECG device that records your heart rhythm over a sustained period of time—usually a 24- to 48-hour period—while you go about your daily activities and even while you sleep. You can fit the monitor into a purse or jacket pocket or wear it over your shoulder by its strap and then continue your normal routine, with two exceptions. First, you can’t take a shower or bath during the period in which you’re wearing the monitor. Second, you are given a small diary in which to note any worrisome symptoms you feel, along with the time they occur. The doctor will later review both your diary and data about your heart’s activity from the monitor, to see if any symptoms you experienced were caused by some underlying heart problem.

Another type of monitor, known as an event recorder, can be activated by the person wearing it to capture the heart rhythm during symptoms. Cardiologists commonly order these devices for people who experience infrequent palpitations (once a week or so) that cause bothersome or potentially dangerous symptoms. Most are worn for one to two months. If you are wearing an event recorder and experience symptoms, you simply press a button, which prompts the device to record your heart rhythm. (Event recorders continuously monitor and record the heart rhythm, but only save the most recent few seconds. When you hit the button, it permanently saves the recording from a few seconds before the button was pressed to a minute or so after.) This information is then transmitted via telephone to the device maker, and from there to your physician.


Exercise stress test

An exercise stress test, also called an exercise tolerance test, indicates whether your heart gets enough blood flow and oxygen when it’s working harder than usual. The test is most commonly ordered if you have symptoms of coronary artery disease or if your doctor wants to assess the effectiveness of your treatment. During this test, the heart’s rhythm and blood pressure are continuously monitored as you walk on a treadmill. You will typically begin walking on a slight incline at a slow pace. If you have had a recent heart attack or are otherwise physically limited, you may be asked to exert yourself even less.

If all is well and you feel up to it, treadmill speed and degree of incline are increased until you need to stop because you feel short of breath, lightheaded, or otherwise uncomfortable. In other cases, the physician may end the test if your blood pressure drops (or rises too high) or abnormalities appear on the ECG. If you are not accustomed to marked physical exertion or have recently had a heart attack, the physician might stop the test after a predetermined period, or after a certain heart rate is reached. When the exercise is over, you are helped to a nearby bed while the ECG continues to record data. Often, the information obtained while you are recovering is the most revealing.

Many people worry that this test could be dangerous to someone with coronary artery disease, possibly even inducing a heart attack. But even though people are asked to push themselves to the limit, the screening is extremely safe if physicians examine you beforehand to make sure that you are healthy enough for it. Fatal complications are rare.

If walking on the treadmill produces symptoms such as chest discomfort, shortness of breath, or dizziness, and if these symptoms are accompanied by ECG changes, the test strongly suggests coronary problems. A test is considered negative if you can perform a normal amount of exercise without symptoms or ECG changes.

However, many people have chest discomfort but no ECG changes, or vice versa. In these cases, the exercise test is of less help and the result will be interpreted as consistent with coronary artery disease, but not definitive. Furthermore, some people with coronary artery disease don’t show any evidence of ischemia in exercise testing because other medical conditions, such as arthritis, prevent them from walking long enough or fast enough to stress their hearts. (For them, other test options exist. See “Nuclear stress test” and “Echocardiography”.)

In addition, exercise testing is less sensitive and possibly less accurate in women. Some doctors believe that women may benefit more from a pharmacologic stress test, which uses medications instead of exercise to make the heart work harder. It’s also possible that women’s breast tissue keeps the leads farther from the heart, distorting the findings and making them harder to interpret.

Finally, almost every physician has heard of someone who had a negative exercise test one week and a heart attack the next, but this is a rare event. Sometimes a negative result may provide false reassurance to someone who had been unable to exercise enough to trigger ischemia during the test. In other instances, a negative result may be accurate, but a heart attack could still occur. For example, an atherosclerotic plaque might not be large enough to cause significant obstruction of a coronary artery during the test, but later suddenly ruptures and leads to the formation of a clot that blocks blood flow.

Stress tests, like all tests, are not foolproof. When the results are unclear, a nuclear stress test can help clarify a person’s diagnosis and risk status.

Radiation risks from heart tests

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Many tests used to diagnose heart disease involve radiation exposure, which is measured in millisieverts (mSv), a designation that reflects the biological effect of radiation on tissues. Radiation offers extraordinary benefits for diagnosing heart disease and other ailments, but it can cause damage to cells that may trigger cancer. Each year, the average person receives about 3 mSv of so-called background radiation from naturally occurring sources of radiation from the Earth and cosmos. This tiny amount has little effect on health. But since the 1980s, the amount of radiation used in medicine has grown so much it now rivals background radiation, adding an average 3 mSv per person each year, says the National Council on Radiation Protection and Measurement. Much of this growth comes from computed tomography (CT) scans (see “Computed tomography”).

The amount of radiation from these scans varies widely, according to a report in The Journal of the American Medical Association (JAMA). Researchers estimated exposures from CT scans at 50 hospitals worldwide and found levels at the highest-dose sites to be six times as high as those at the lowest doses. The variability stemmed from differences in scanner models, how the machine was operated, and whether radiation-reducing techniques were used. The average radiation exposure from a single new-generation test was equal to the exposure from 600 conventional chest x-rays.

Just how dangerous are these levels? A scientific advisory on the topic from the AHA offers some perspective. Your risk of developing some type of cancer during your lifetime is 41%, and the risk of dying as a result is 21%. The relative risk of dying of cancer from the radiation in a heart CT scan is very small in comparison—an estimated increase of about 0.05% above the 21% background risk. In addition, radiationinduced cancers don’t occur until decades after exposure, making the cancer risk even less concerning for older people, who are likely to die from other causes (including heart disease) before developing cancer.

However, a second JAMA study that looked at heart imaging tests on patients at a New York teaching hospital found that many received “alarming and probably unsafe” levels of medical radiation from the tests. About one-third of the tests were done in people without symptoms of heart disease and therefore would not prompt changes in treatment. The findings underscore the AHA’s recommendation that tests involving radiation exposure should be ordered only after “thoughtful consideration,” including whether an alternative test might do instead. Don’t request or agree to any type of medical test unless it will give you and your doctor important information about your health or body. And ask about receiving the lowest dose of radiation possible.


Pharmacologic stress test

People who are older or out of shape and those with arthritis, lung disease, vascular disease, certain baseline ECG abnormalities, or other medical conditions typically cannot exercise enough to undergo the traditional exercise tolerance test. In such situations, a pharmacologic stress test, which substitutes medication for exercise, provides another option. The medication increases the heart’s need for blood, allowing doctors to detect blockages that obstruct the supply of blood.

Two strategies are commonly used in pharmacologic stress tests. In one, the medication used—dobutamine, which acts like adrenaline and is sometimes combined with atropine—increases the amount of work the heart does, thereby increasing its need for oxygen-rich blood, much as exercise does. Echocardiography (see below) is generally used to monitor abnormalities induced by dobutamine. A second strategy is to give dipyridamole (Persantine) or adenosine (Adenocard), medications that cause the coronary arteries to widen, producing a fourfold increase in blood flow. Blood flow does not increase normally in blocked arteries. Nuclear imaging (see “Nuclear stress test”) is usually used to detect blockages revealed by dipyridamole or adenosine.

Pharmacologic stress tests aren’t for everyone. People with asthma, emphysema, carotid artery disease, or aortic stenosis should not take dipyridamole or adenosine, while anyone with uncontrolled hypertension or abnormal heart rhythms should not take dobutamine.


Nuclear stress test

Nuclear stress tests are similar to the other exercise stress tests, but the images are usually taken with single-photon emission computed tomography (SPECT), in which a camera that records x-ray images circles around the heart, taking pictures from many angles. A computer uses this information to build a more detailed and precise image of the heart.

Because nuclear imaging is more expensive and takes longer than a traditional exercise tolerance test, it’s not usually the first test used for diagnosing coronary artery disease. It’s used primarily for people with abnormal ECGs who either have inconclusive exercise test results or can’t do a conventional exercise test because arthritis, stroke, lung disease, or other ailments restrict their mobility.

During a nuclear imaging test, you will either exercise on a treadmill to make your heart work harder (see “Exercise stress test”) or be injected with a medication that can induce ischemia (see “Pharmacologic stress test”). You also get an injection of a tracer, a slightly radioactive substance (technetium or thallium) that circulates in the bloodstream (see “Radiation risks from heart tests”). The SPECT scanner tracks blood flow through the heart by detecting these radioactive particles in the bloodstream. The tracers concentrate in areas of the heart muscle that have a good blood supply, while areas with no blood supply, such as scars from a previous heart attack, won’t collect the radioactive particles.

You wait a short time for the tracers to reach your heart, then lie down as the scanner rotates around you taking pictures. A second series of images is taken later on, when the heart is at rest. When comparing the two sets of images, doctors look to see whether abnormalities present during stress disappear once the stress has passed. This difference would suggest that the heart muscle is in danger from coronary artery disease. In people with coronary artery disease, ischemia occurs under periods of stress, but not otherwise. Any abnormalities that appear on both sets of images indicate old heart damage, perhaps from an earlier heart attack.


Echocardiography

Some cardiologists use echocardiography instead of nuclear imaging to detect ischemia during a cardiac stress test. As with nuclear imaging, echocardiography (sometimes referred to as a stress echo or ultrasound) is appropriate for people at high risk for a heart attack who can’t have an exercise tolerance test or whose exercise test was inconclusive.

With echocardiography, sound waves provide a video image of the beating heart (see Figure 7). After exercise or an injection of one of the ischemia-inducing drugs, an echocardiogram can detect if a portion of the heart muscle with inadequate blood supply is contracting abnormally.

It’s difficult to compare echocardiography with nuclear imaging because studies show that their accuracy and effectiveness vary considerably from one imaging laboratory to the next. Therefore, when making the choice, you and your doctor should take into account which test is preferred and used most often by the institution where you’ll be evaluated.

Figure 7: Echocardiogram

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Echocardiography uses sound waves to create still and moving pictures of the heart. These images show the size, shape, and structure of the heart and give important clues about how it is working.


Coronary angiogram

The “gold standard” test used in diagnosing coronary artery disease is a coronary angiogram (also called coronary angiography or arteriography). This test is used to confirm a diagnosis in people who are suspected of having coronary artery disease on the basis of noninvasive tests, such as the exercise tolerance test, or whose tests were inconclusive. It’s also recommended for some people known to have coronary artery disease, to determine the location and extent of arterial blockages, and for those being considered for angioplasty or coronary artery bypass surgery.

A coronary angiogram is a type of cardiac catheterization (a procedure in which a thin tube called a catheter is inserted into a coronary artery). About 1.3 million cardiac catheterizations are performed in the United States each year—mostly in hospitals with special laboratories designed for this purpose.

For the test, the cardiologist inserts the catheter into a blood vessel elsewhere in the body (usually an arm or leg) and threads it deeper into the circulatory system until it reaches the coronary arteries. He or she then squirts a dye that can be seen on x-rays into the coronary arteries. A technician takes x-ray films during the procedure, and these films help reveal whether and how severely the coronary arteries are narrowed (see Figure 8).

Figure 8: Coronary angiogram

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This angiogram shows a narrowing (see arrow) in the left anterior descending coronary artery.

Although the catheterization itself usually takes an hour or less, health care personnel must keep you under observation for several hours after the procedure to make sure that there is no internal bleeding where the catheter was inserted. If a leg vessel was the point of entry, you must lie down for about four to six hours, usually with a weight compressing the catheterization site. If you don’t have angina, internal bleeding, or other complications, you may be able to go home later that day.

An angiogram should not be painful and is remarkably safe when performed by experienced physicians. However, it involves some risks. The most common complications are bleeding where the catheter was inserted or the formation of blood clots in the vessel. Other possible complications include heart rhythm abnormalities, infections, and allergic or kidney reactions from exposure to the contrast dye. Stroke, heart attack, and major bleeding are uncommon.

Some women who have alarming stress tests have what look to be clear coronary arteries on an angiogram. Technically, this is not because the angiogram has missed an atherosclerotic plaque. Rather, these women may have coronary microvascular disease (see “What is coronary microvascular disease?”). They have narrowings in essential blood vessels that are too small to show up on an angiogram, which can only peer into larger blood vessels. Trouble in the heart’s smallest arteries can cause classic symptoms of heart disease, like chest pain and shortness of breath, along with less well-recognized ones such as diffuse discomfort in the chest or unusual exhaustion, even when the arteries register as open. Thus the test result may lead to a false sense of security, or frustration.


Computed tomography

Traditional computed tomography (CT) devices are doughnut-shaped machines that house rotating x-ray tubes that take pictures of thin “slices” of your anatomy. A computer assembles these images into a three-dimensional picture. Older CT scans weren’t fast enough to capture the beating heart, since the heart’s movement blurred the images of the arteries on most scans. It was like trying to take a photograph of a speeding car with a slow shutter speed.

Two developments now make it possible to get images sharp enough to actually see blockages inside the coronary arteries. First, beta blockers, such as atenolol (Tenormin) and metoprolol (Lopressor, Toprol XL), can slow down the heart, so doctors can get a better look.

Second, technology has improved, providing the equivalent of much faster film to photograph that speeding car. Traditional CT devices typically had four internal scanners. Now, 64 scanners have become standard, and devices with 256 or even 320 scanners are used at some institutions. The greater the number of scanners, the better the resulting image. In a process called multidetector computed tomography (MDCT), these devices simultaneously take dozens of snapshots from different angles. These snapshots are then used to reconstruct a complete image of the inner workings of the arteries. A different technology, electron beam CT (EBCT), takes pictures with a rotating beam of electrons that circles the body far faster than an x-ray camera.

The advantage of CT is that it can show whether people have coronary artery blockages without subjecting them to a coronary angiogram. (That’s why these scans are sometimes referred to as “CT angiograms.”) Although coronary angiograms are generally safe, they carry a low but real risk for complications such as stroke, heart attack, kidney problems, and even death.

Even so, there are several issues to consider before undergoing a CT angiogram. First, not all CT scanners are created equal. If you opt for a CT angiogram, make sure the device is the latest generation. Second, although the scans are noninvasive, they do carry risks (see “Radiation risks from heart tests”). Perhaps the most significant issue, though, is that the scans may reveal partial blockages that might not otherwise have been visible. While this may seem like a good thing, it’s not clear that it is. Some people will want to “fix” these with angioplasty and coronary artery bypass surgery rather than trying lifestyle changes and medications. This can lead to greater expense and greater risk for complications, and it is not clear that going after these narrowings in people who have no symptoms helps them avoid heart attacks or live longer. Nor is it clear yet whether using CT scans in place of angiograms will improve health outcomes—ultimately the most important consideration. For these reasons, many insurance companies do not pay for CT angiograms, and they are not routinely used.


Coronary artery calcium tests

MDCT and EBCT can also be used to measure the amount of calcium in the coronary arteries. Calcium is an elemental part of the body’s response to the cycle of inflammation, damage, and repair that results in atherosclerotic plaque. Calcium scores indicate whether a person has calcium-laden plaque in the coronary arteries.

Guidelines from the AHA advise coronary artery calcium scans only for people who fall into the gray zone of intermediate risk for heart disease. For these people, a low calcium score (0–99) could calm worries about having a heart attack, while a high score (400 and over) might tilt the scales in favor of stepping up prevention efforts. Beware, however, that calcium scores may be less reliable for people in certain racial groups. An African American, for example, may receive a low calcium score, but that doesn’t necessarily mean he or she is at low risk for a heart attack.

The scans aren’t useful for people at high risk or who have already been diagnosed with heart disease, since the results wouldn’t change prevention or treatment strategies. The scans are sometimes not covered by insurers. Finally, the next generation of CT scanners, with ever-improving image quality, may make coronary calcium scanning obsolete.

A heart attack, known medically as a myocardial infarction, occurs when one of the coronary arteries is fully or partially blocked (see Figure 9, below). Each coronary artery supplies blood to a specific part of the heart’s muscular wall, so a blockage causes pain and malfunction in the area that the affected artery serves. Depending on the location and the amount of heart muscle involved, this malfunction can seriously interfere with the heart’s ability to pump blood. Also, some of the coronary arteries supply areas of the heart that regulate heartbeat, so a blockage sometimes causes potentially fatal abnormal heartbeats called cardiac arrhythmias.

The classic symptoms of a heart attack include crushing chest pressure; pain radiating to the neck, jaw, back, or arm; sweating and shortness of breath; and sudden “indigestion” or “heartburn” that isn’t relieved by antacids. But some people, particularly women, experience other symptoms (see Table 6).

Table 6: Common symptoms of a heart attack

Seek help immediately if you think you are having a heart attack. Although the most common sign of a heart attack in both men and women is the classic one—pain in the center of the chest that spreads through the upper body—this symptom doesn’t always occur, particularly in women. In fact, one study reported that 43% of women who had heart attacks did not recall any type of chest pain. Instead, the women often reported what some doctors call nonclassic symptoms, listed here. However, you should be aware that heart attack symptoms do not follow strict gender lines; men and women can both experience either classic or nonclassic symptoms, so it’s good to be familiar with both.

Classic symptoms (more common in MEN)

  • Pressure, aching, or tightness in the center of the chest

  • Pain or discomfort that radiates to the upper body, especially shoulders or neck and arms

  • Sweating

  • Dizziness

Nonclassic symptoms (more common in WOMEN)

  • Shortness of breath

  • Weakness

  • Nausea or vomiting

  • Dizziness

  • Back or jaw pain

  • Unexplained fatigue

If you have the symptoms of a heart attack, call 911. Traveling to the hospital by ambulance rather than having someone drive you means you’ll likely arrive faster and be treated more quickly once you get there. You should also chew one standard (325 mg) aspirin as soon as possible. Make sure it’s a regular aspirin, not enteric-coated, which will act slowly even if chewed. Chewing the pill gets its anti-clotting chemicals into your bloodstream much faster than if you swallow it. In one study, platelet activity (which contributes to clots) dropped by 50% within five minutes in people who chewed an aspirin. That same effect took 12 minutes if the aspirin was swallowed whole.

Every minute counts. In one landmark study, people who received treatment within one to two hours were only half as likely to die as those who were treated four to six hours after the onset of symptoms. The primary goal in treating most heart attacks is to unblock the artery and restore blood flow to the heart as fast as possible with medication or surgery. Doing so will minimize the damage to the heart tissue.

Figure 9: Your heart’s “weakest links”

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Blockage can occur in any of your coronary arteries. Two common sites are the right coronary artery (A) and the left anterior descending artery (B). When blockages occur in these locations, heart damage can result in the adjoining areas (shown shaded).


Is it a heart attack?

Emergency department physicians or staff must first determine whether you are having a heart attack, an episode of angina, or something completely unrelated (see “Other causes of chest pain that may mimic angina”). The American College of Cardiology recommends that a diagnosis of heart attack be made when two of the following three criteria are met:

  • symptoms of a heart attack (see Table 6)

  • ECG abnormalities suggestive of a heart attack

  • blood tests that reveal elevated levels of troponin (a protein that signals damage to heart muscle).

Because heart attacks are sometimes hard to distinguish from other causes of chest pain, your physician may also order additional tests, such as echocardiography, nuclear scans, and cardiac catheterization, before making a diagnosis.


ECG and blood testing

Emergency room staff often do an immediate ECG; sometimes this is even done in the ambulance during the ride to the hospital. In many cases (but not all), the ECG helps to determine whether you are having a heart attack, and if so, what type of heart attack. But the ECG abnormalities that accompany a heart attack may be atypical, subtle, or even absent. That’s why doctors always use blood tests to confirm a heart attack diagnosis.

When heart cells die, they release enzymes, the chemicals that trigger vital tissue functions. Some of these enzymes are specific to the heart and aren’t produced in any other tissue in large quantities. Doctors measure the blood levels of these enzymes at intervals over time. Because dying heart cells release different enzymes at different rates, the blood tests can help pinpoint the time the heart attack occurred—information that is particularly useful when symptoms are vague. In addition, the more cells that die, the higher the blood levels of these different enzymes. Doctors can use this information to estimate the amount of heart tissue that has been destroyed.

If doctors suspect that you are having a heart attack, they will probably test your blood for either troponin I or troponin T, which are proteins that begin to rise within minutes after a heart attack.


Treating a heart attack

If you have a heart attack and reach the hospital in time, chances are very good that you will walk out of the hospital within a week or even sooner.

When you reach the hospital, you’ll go first to either an intensive care unit (or coronary care unit), where there are nurses and doctors with specialized training and equipment to monitor your condition and treat emergencies, or to the cardiac catheterization laboratory to open a coronary artery, if it’s blocked.

Treatment of a heart attack involves several strategies, some of them conducted almost simultaneously:

  • reopening the blocked artery (reperfusion)

  • preventing further blood clots from developing

  • reducing the oxygen needs of the heart muscle

  • monitoring for and controlling complications

  • treating any complications that develop

  • assessing short- and long-term risk.


Immediate treatment

During the early stages of a heart attack, heart cells are dying rapidly from a lack of oxygen. For most people, the immediate goal is to restore blood flow to the heart, by reopening the blocked artery and preventing further blood clots from developing. Such reperfusion therapy can restore the flow of oxygen-rich blood to the heart muscle, sometimes before any serious damage occurs.

There are two main ways to restore blood flow: with angioplasty (with or without stenting), or with thrombolytic agents—also known as “clot busting” drugs because they help break down clots in blood vessels. (Coronary artery bypass surgery is used much less frequently.) Angioplasty saves more lives than clot-busting drugs and is less likely to cause complications. But if a cardiac team is not available or the hospital is not equipped to do angioplasty, clot-busters provide another lifesaving option.

Time is of the essence in all cases, however: the faster blood flow is restored to the heart, the greater your chances of surviving and recovering. For people whose ECGs and other tests suggest they are having a heart attack, the goal is to either undergo angioplasty within 90 minutes of arriving at the hospital or to receive clot-busting drugs within 30 minutes of arrival.

Results from a large international trial further emphasize the need to act quickly. For people with chest pain after a heart attack, angioplasty was beneficial only if performed within 24 hours after symptoms began. In this trial, those who underwent angioplasty more than 24 hours after the start of symptoms and then received standard medication treatment (at least aspirin, an ACE inhibitor, a beta blocker, and a statin) had only slightly fewer second heart attacks, cases of heart failure, or deaths than those who received medications alone. This trial reinforces the importance of recognizing heart attack symptoms quickly and getting to the hospital as fast as you can.

Fast fact:

Two-thirds of Americans can’t identify the signs of a heart attack and say what needs to be done when one strikes.

In people with less severe heart damage, the situation is not quite so dire in the short term, and you may be monitored for a longer period before your doctors recommend a particular treatment. However, early, invasive treatment seems to result in better outcomes for people with these diagnoses.

Medications given to open blocked arteries include clot-busting drugs, such as alteplase (Activase), as well as drugs that prevent new blood clots, such as aspirin and heparin (see “Medications for heart disease”). These drugs (especially the clot busters) aren’t appropriate for everyone, since they can cause bleeding complications in people over age 70, people with severe high blood pressure (greater than or equal to 180/100), and people with a history of strokes or certain other conditions.


Minimizing the heart’s oxygen needs

At the same time that blood flow is being restored, doctors take steps to minimize the heart’s oxygen needs. During the first few hours after a heart attack, bed rest helps reduce the heart’s oxygen requirements; so do certain medications, beta blockers, nitrates, analgesics, sedatives, ACE inhibitors, and angiotensin-receptor blockers (see “Medications for heart disease”).


Monitoring and follow-up

For the first few days after a heart attack, you’ll probably need to rest in bed and have your heartbeat continuously monitored to make sure that no dangerous rhythms develop. You may need supplementary oxygen to fuel your heart muscle and an intravenous (IV) line in your hand or arm so you can receive medications.

In the coronary care unit, nurses are highly trained to recognize electrical disorders and to administer heart drugs. An array of devices and machines—defibrillators, ventilators, pacemaker equipment, and other tools for monitoring and maintaining heart function—stand at the ready.

In most hospitals, as soon as you are stable you’ll be encouraged to sit up, walk to the bathroom, and stroll the halls. This progressive exercise helps keep blood clots from forming. It also starts strengthening the heart and is a good check of its function—lack of chest pain is an excellent sign.

Most people don’t have major problems after a heart attack and can leave the coronary care unit for a step-down unit, or intermediate care, within a day or two. Intermediate care units have much of the same monitoring equipment as coronary care units do; the difference is in the ratio of nurses to patients. In intermediate care, each nurse cares for three to five patients, compared with only two in coronary care.

The last step in the hospital phase of treatment is evaluating your risk of having another heart attack—and teaching you how to minimize that risk. This risk assessment involves several types of tests.

Some people who have smooth recoveries may undergo a low-level exercise tolerance test before leaving the hospital. You might get one if you did not have angioplasty or if you have several blocked arteries of unknown severity. The low-level test differs from the conventional exercise tolerance test in that you stop exercising after a predetermined number of minutes of low-level exercise on a treadmill, even if you show no problems or symptoms. The goal is to determine whether you are stable enough to resume a reduced level of physical activity at home. If the test is negative—that is, it reveals no problems—you’ll be able to go home. The test can also help you learn how much exertion is safe and appropriate during the next phase of the healing period. Most people are reassured to learn that the period of imminent danger has passed and that they can resume a fairly normal life over a period of several weeks.

A low-level exercise test that reveals abnormalities—such as exertion-related chest pain, fluctuations in heart rhythms, or changes in blood pressure—generally indicates that parts of the heart remain at risk for further damage. In such cases, cardiologists may suggest cardiac catheterization, which can reveal whether angioplasty or coronary artery bypass surgery might improve blood flow to the heart and reduce the chances of another heart attack.


Healing your heart: Cardiac rehabilitation

Right after having a heart attack or undergoing angioplasty or bypass surgery, you’ll need time to recuperate. In addition to the emotional impact of a brush with mortality, you’ll feel run-down and physically depleted. Even short periods of bed rest and inactivity weaken the muscles, heart, and lungs. Blood loss from surgery, angioplasty, and multiple blood tests can leave you with low blood levels of iron (anemia), a common cause of fatigue. Your appetite may have flagged, and not eating and drinking saps your energy. Finally, your body may be adjusting to a new regimen of medications, which can also cause you to feel weak.

Not that long ago, extended rest was what the doctor ordered after a heart attack or heart trouble. Taking it easy, the thinking went, wouldn’t stress the heart and would help it heal more quickly. Now, doctors know that inactivity doesn’t help your heart or the rest of your body. Exercise not only strengthens your heart, but it also helps your muscles use oxygen more efficiently, easing the heart’s workload.

While you’re in the hospital, you’ll be encouraged to walk to the bathroom and even walk the halls. After you leave the hospital, your doctor will probably advise you to move around at home. A month or so after a heart attack or bypass surgery, and sooner after angioplasty, you should start cardiac rehabilitation, a medically supervised program designed to help you heal your heart and keep it healthy. The centerpiece of cardiac rehabilitation is usually a structured and supervised exercise program. Rehab programs also teach people about heart disease and how to manage it. Many also offer classes or information on weight management, nutrition, stress reduction, smoking cessation, and returning to work. The staff typically includes doctors, nurses, exercise specialists, physical and occupational therapists, nutritionists, and psychologists.


Why rehab?

Cardiac rehabilitation programs have been shown to reduce deaths by up to 25% during the few years following a heart attack or cardiovascular procedure. That’s at least as good as taking aspirin, a beta blocker, a statin, or a combination of these. Participating in rehab can also improve your quality of life. For one thing, you’ll have peace of mind when you exercise, knowing that you’ll be closely monitored for any potential problems. Some people also enjoy the shared camaraderie of working out with people who understand what they’ve been through. Others benefit from group sessions or classes, where they’re able to ask questions and learn from one another. Some cardiac rehabilitation programs also offer support groups for family members.

Doctors sometimes overlook the importance of referring their patients to cardiac rehab, so if you qualify (see “Do you qualify for cardiac rehab?”), ask your physician about local facilities. Despite the benefits, fewer than 30% of eligible patients take part in rehab. For people 65 and older, participation is even lower—just 14%. A shortage of programs nationwide and accessibility issues (for instance, some facilities aren’t near public transportation or the classes are at inconvenient times) may explain these low figures. Private insurers or Medicare usually cover the cost, although you may have a copayment. Schedules vary among different programs, but people usually come to the facility at least once a week and up to three times a week, from one to several hours. Some people attend for just a few weeks, while others continue for months.

Do you qualify for cardiac rehab?

Anyone can sign up for cardiac rehab; the catch is that insurers will typically pay for it only if one of the following applies:

  • You’ve had a heart attack.

  • You’ve undergone angioplasty, with or without a stent.

  • You’ve had bypass surgery.

  • You have stable angina.

  • You’ve had a heart valve repaired or replaced.

  • You’ve undergone a heart or lung transplant.


Choosing a facility

First, check to see that the program is certified by the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR; see “Resources”). There are between 3,500 and 4,000 cardiac rehab centers nationwide, and about 1,500 have been certified by the AACVPR. (You can find a certified program near you at www.health.harvard.edu/cvrehab.) The following list of questions can help you decide on a facility:

  • Does the staff include trained cardiac nurses, exercise specialists, dietitians, and mental health specialists?

  • Is there a doctor on the premises?

  • Is the staff ratio at least one to every four patients?

  • Is the staff certified in basic and advanced life support skills?

  • Does the program offer workshops and counseling?

  • Are assessments and treatment plans individualized?

  • Will someone on staff file your insurance claim?

  • Will the staff stay in regular contact with your cardiologist?

  • Is there a post-rehab program available that would allow you to continue to exercise at the facility for a fee?

  • While visiting a facility, look for these features:

  • a variety of exercise equipment such as treadmills, elliptical trainers, stationary bikes, and step machines

  • equipment that’s modified for elderly or disabled patients

  • free weights, wall pulleys, and rowing machines. 

Lifestyle changes are an essential first step in treating coronary artery disease (see the special section of this report, “Lifestyle habits that help your heart”). But most people also need at least two medications to reach their cholesterol and blood pressure goals and keep the blood flowing freely through their arteries.

Heart disease medications that are taken on a daily basis fall into two broad groups, with some overlap. One group, known as disease-modifying drugs, includes medications that lower your chances of dying from heart disease. There are five main classes of these, including aspirin (which prevents blood clots), statins (which lower cholesterol levels), and beta blockers (which reduce heart rate). The other two—both of which bring down blood pressure and reduce atherosclerosis in the artery wall—are angiotensin-converting-enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs).

The second group, known as symptom-controlling drugs, help reduce symptoms of angina by easing the heart’s workload. These include nitrates and calcium-channel blockers, as well as beta blockers, ACE inhibitors, and ARBs.

The specific combination of drugs you take will depend on your particular symptoms and risk factors. Figure 10 shows each of the major classes of medications typically prescribed to people with heart disease and how they work in the body. The following summaries feature additional information about the most commonly prescribed drugs.

Figure 10: Medications for treating heart disease and how they work

image


Aspirin

This common, inexpensive pill helps protect survivors of heart attack and stroke from subsequent heart attacks and death, and even helps reduce the number of deaths that occur within the first hours following a heart attack. Dozens of studies involving tens of thousands of people have shown that daily low-dose aspirin reduces the risk for a repeat heart attack or stroke by about 25%. For men, the main benefit is preventing a heart attack; for women, it is preventing an ischemic stroke, the most common type of stroke, which is caused by a blockage in an artery feeding the brain. Almost everyone with coronary artery disease benefits from taking daily low-dose aspirin. The exception would be individuals at high risk of developing aspirin-related bleeding complications.

For both men and women, gastrointestinal bleeding and hemorrhagic (bleeding) stroke are the main risks of aspirin. As with heart disease, the risk of bleeding complications rises with age. Aspirin-induced bleeding is also more likely to occur in people who have a history of uncontrolled high blood pressure, ulcers, or bleeding problems and in those who regularly take ibuprofen (Advil, Motrin), another nonsteroidal anti-inflammatory drug, or warfarin (Coumadin, Jantoven).

The U.S. Preventive Services Task Force recommends a dose of 81 mg a day, the amount in a baby aspirin, which seems to work just as well as higher doses, with fewer bleeding problems. In theory, taking aspirin with a protective coating, known as enteric-coated aspirin, should help avoid ulcers and other stomach-related side effects, as the coating allows the aspirin to pass through the stomach to the intestine before dissolving. But aspirin in the bloodstream irritates the stomach just as much. (No matter where it dissolves in the body, aspirin prevents the production of substances called prostaglandins that protect the stomach.) In addition, there’s some evidence that not all the aspirin in a coated pill gets into the bloodstream.

A small number of people—likely just 2%—may not experience all or even any of aspirin’s anticlotting benefits. This problem, called aspirin resistance, seems to be more prevalent in women and in people who smoke, are obese, have diabetes, or have a history of clots forming inside a stent (see “How stents work”). Doctors once thought aspirin resistance was much more common, but research now suggests the real problem is that people just aren’t taking the aspirin. In rare cases, however, people who take aspirin faithfully still develop blood clots. Raising the dose may overcome the resistance.


Blood pressure medications

The five categories of drugs used to treat high blood pressure are equally effective for most people (see Table 7). But keep in mind that most people do not get their blood pressure under control with the starting dose of the first drug chosen.

Some doctors increase the dosage of the first drug to see if it will bring blood pressure down to target levels. A second approach is to use low doses of two or more blood pressure drugs that work in different ways. This approach minimizes the likelihood of side effects, but may be harder to follow, as it requires taking two or more pills per day. It may also be more expensive for the person being treated, as he or she may face additional copayments or out-of-pocket expenses for the drugs. A compromise approach is to use combination drugs that include, for example, both an ACE inhibitor and a low-dose diuretic (see “Combination medications”). This is convenient, but many combinations are available only in brand-name forms and are thus more expensive.

Table 7: Blood pressure medications

Generic name (brand name)

Side effects

Comments

Thiazide diuretics

chlorothiazide* (Diuril)

Weakness, confusion, potassium depletion, gout, fatigue, thirst, frequent urination, lightheadedness, muscle cramps, diarrhea or constipation, increased sensitivity to sunlight, allergic reaction in people allergic to sulfa drugs, erectile dysfunction.

Inexpensive, generally well-tolerated; often the first-line treatment for high blood pressure.

Can cause low potassium levels and may require the use of potassium supplements.

chlorthalidone* (Hygroton)

hydrochlorothiazide* (Esidrix, HydroDiuril, Microzide)

indapamide* (Lozol)

metolazone* (Mykrox, Zaroxolyn)

spironolactone (Aldactone)

ACE inhibitors

benazepril* (Lotensin)

Persistent dry cough, altered taste sensation, rash and other allergic reactions; may cause kidney damage and, rarely, decrease white blood cells.

ACE inhibitors are usually taken once or twice a day; may be used alone or in combination with other medications.

Captopril may take several weeks to achieve the full effect; kidney function should be monitored; usually taken two or three times per day.

captopril* (Capoten, Capozide)

enalapril* (Vaseretic, Vasotec)

fosinopril* (Monopril)

lisinopril* (Prinivil, Zestril)

moexipril* (Univasc)

quinapril* (Accupril)

ramipril* (Altace)

trandolapril* (Mavik)

Angiotensin-receptor blockers (ARBs)

candesartan (Atacand)

Persistent cough, elevated potassium levels, dizziness, headache, drowsiness, diarrhea, abnormal taste sensation, rash.

May be an alternative for people who can’t take ACE inhibitors.

eprosartan (Teveten)

irbesartan* (Avapro)

losartan* (Cozaar)

olmesartan (Benicar)

telmisartan (Micardis)

valsartan (Diovan)

Beta blockers

atenolol* (Tenormin)

Less likely than propranolol to cause wheezing and spasm of arteries outside of the heart.

Atenolol and metoprolol are “cardioselective” beta blockers, which means they can be used with caution by people with asthma, although they can still cause side effects.

metoprolol* (Lopressor, Toprol XL)

nadolol* (Corgard)

Can worsen or provoke asthma or pain in legs because of narrowed arteries; can worsen heart failure; can provoke Raynaud’s phenomenon (spasm of blood vessels to hands); sometimes cause fatigue or depression, impotence, hallucinations, or bad dreams (elderly people are more prone to these latter side effects).

Nadolol is a long-acting drug usually taken once per day; do not stop taking suddenly.

propranolol* (Inderal, Inderide)

Propranolol is available in short-acting and extended-release forms.

timolol (Blocadren, Timolide)

Timolol is usually taken twice per day.

Other beta blockers not included in this table include pindolol (Visken), acebutolol (Sectral), labetalol (Normodyne, Trandate, others),
penbutolol (Levatol), carteolol (Cartrol), betaxolol (Kerlone), bisoprolol (Zebeta), and combination medications with a beta blocker as one ingredient. Although most of these medications are often used to treat hypertension, not all of them have been evaluated in large, randomized trials for their ability to help people who have coronary artery disease.

Calcium-channel blockers

amlodipine* (Lotrel, Norvasc)

Higher doses cause similar side effects to those caused by nifedipine.

Can be taken once daily; with less than
the highest doses, possibly fewer side effects than from nifedipine.

felodipine* (Plendil)

diltiazem* (Cardizem, Dilacor XR, others)

Headache, flushing, nausea, weakness, drowsiness, fluid retention, constipation, excessively slow heart rate.

Low rate of side effects in most people; available in long-acting preparations.

nicardipine* (Cardene)

Headache, swelling of legs (edema), flushing, palpitations, dizziness, constipation.

Long-acting preparation may reduce side effects, but swelling of legs and ankles remains a problem with both short- and long-acting formulations.

nifedipine* (Adalat, Nifedical XL, Procardia)

verapamil* (Calan, Verelan, others)

Constipation, excessively slow heart rate, worsened heart failure.

Available in long-acting preparations; constipation limits use in some people.

*An asterisk indicates the drug is available in a generic version or is expected to be within the near future.


Cholesterol medications

Among the drugs used to lower cholesterol, statins are by far the most effective and therefore most widely used (see Table 8). Results from large trials show that taking a statin reduces the chances of having a heart attack or stroke, needing bypass surgery or angioplasty, or dying of heart disease. Over all, for every 40-point reduction in LDL achieved with a statin, the risk drops by 20%. The greater your chances of having a heart attack or stroke or dying of cardiovascular disease, the more a statin can help. In addition to lowering LDL, these drugs also help stabilize cholesterol-filled plaque in artery walls, promote the growth of new blood vessels, and calm inflammation. For people with coronary artery disease, the target for LDL is under 100 mg/dL, and for some may even be under 70 mg/dL.

Getting the most from your statin

You can do several things to make sure your particular statin is working as well as it can.

  • Take lovastatin with food. This almost doubles the amount of medication that gets into your bloodstream.

  • Take lovastatin, simvastatin, or fluvastatin with your evening meal. Statins work by blocking a key cholesterol-making enzyme in the liver that is most active at night. Because the body tends to break these statins down at a fairly rapid clip, timing is important. Atorvastatin, pravastatin, and rosuvastatin last longer in the body so it doesn’t matter when you take them.

  • Limit grapefruit juice if you take lovastatin, simvastatin, or atorvastatin. Grapefruit juice increases blood levels of these three, but doesn’t usually affect the other statins. A glass a day is okay, but don’t overdo it.

  • Beware of drug interactions. When talking with your doctor about a statin, mention all other medications and dietary supplements you are taking to avoid potentially harmful interactions. Drugs that interact with statins include (but aren’t limited to) some antibiotics and antifungal medications, some calcium-channel blockers, and fibrates. If you are on other medications, you may want to try pravastatin, which is less likely than the other statins to interact with other medications.

Other cholesterol-lowering medications may also be beneficial for you, depending on your circumstances. Bile acid binders lower LDL cholesterol by 15% to 30%, depending on the daily dose and whether they are combined with a statin. If you have high triglycerides in addition to high LDL, fibric acid derivatives may help. They reduce triglycerides by 20% to 50% and raise HDL levels by 10% to 15%, but have only a modest effect on LDL.

If you have low HDL cholesterol, your doctor might recommend adding niacin, although recent studies have shown that niacin doesn’t add much extra cardiac protection when combined with a statin. Niacin alone can reduce LDL levels by 15% or so, lower triglycerides even more, and boost HDL by as much as 20%. Taken in addition to a statin, niacin lowers LDL another 10%.

Another drug in a class of its own is ezetimibe (Zetia), which lowers LDL cholesterol by about 20%. Vytorin, a drug that combines ezetimibe with sim-vastatin, lowers LDL levels another 15% to 23%. Other cholesterol-lowering combination drugs include Advicor (lovastatin plus niacin) and Caduet (atorvastatin plus amlodipine).

Table 8: Cholesterol-lowering medications

Generic name (brand name)

Side effects

Comments

Statins

atorvastatin (Lipitor)

Abdominal pain, constipation, diarrhea, indigestion, nausea, flatulence, heartburn, dizziness, fatigue, headache, rash, blurred vision, muscle pains, damage to muscle or liver, sleep disturbances.

Do not take if you drink heavily or have liver disease. Use with caution if you take gemfibrozil, cyclosporine, clofibrate, erythromycin, or niacin. Can increase the effect of warfarin.

For rosuvastatin (Crestor): Take the lowest starting dose if you are over 65, have hypothyroidism or kidney disease, or are Asian American.

(Also see “Getting the most from your statin”.)

fluvastatin (Lescol)

lovastatin* (Altoprev, Mevacor)

pitavastatin (Livalo)

pravastatin* (Pravachol, Pravigard PAC)

rosuvastatin (Crestor)

simvastatin* (Zocor)

Bile acid binders

cholestyramine* (LoCholest, Questran)

Constipation, heartburn, “bloated” feeling, nausea, flatulence, tendency to bleed easily; decreased absorption of certain drugs and vitamins A, D, and K. May elevate triglycerides.

Do not take if you have familial dysbetalipoproteinemia (a very high triglyceride level) or a history of severe constipation. Use with caution if you have moderately elevated triglycerides. Take any other medications at least one hour before or four hours afterward. Vitamin supplementation may be necessary. Colesevelam also helps lower blood sugar levels, and is less likely to cause side effects than the other two medications.

colesevelam (WelChol)

colestipol* (Colestid)

Cholesterol-absorption inhibitor

ezetimibe (Zetia)

Uncommon but may include fatigue, gastrointestinal problems, muscle pain, fever, headache, runny nose, sore throat.

Helpful for people who have not responded to statins. Boosts LDL-lowering effect of statins, but no evidence for heart disease protection.

Cholesterol-lowering combinations

ezetimibe plus atorvastatin (Liptruzet)

Headaches, muscle pain, allergic reaction, liver problems, inflammation of the pancreas, nausea, gallstones, inflammation of the gallbladder.

Unclear whether this combination strategy will prevent more heart attacks and deaths than other treatment approaches.

ezetimibe plus simvastatin (Vytorin)

Fibric acid derivatives (fibrates)

clofibrate (Atromid-S)

Nausea, vomiting, diarrhea, indigestion, flatulence, abdominal pain, headache, cardiac arrhythmias, dizziness, fatigue, muscle pain and weakness, rash, hair loss, abnormal liver or muscle enzymes.

Do not take if you have liver problems, severe kidney problems, or gallbladder disease. Avoid if in combination with statins. Can increase the effects of warfarin. Liver functions and blood counts should be checked before and throughout therapy.

fenofibrate* (Lofibra, Tricor)

gemfibrozil* (Lopid)

Niacin

niacin/nicotinic acid* (Advicor, Niacor, Niaspan)

Flushing (especially with crystalline preparations), rash, headache, nausea, vomiting, diarrhea, flatulence, indigestion, low blood pressure, elevated uric acid blood levels, high blood sugar, peptic ulcer activation, cardiac arrhythmias, dry skin, abnormal liver enzymes (especially with sustained-release preparations).

Especially effective in combination with bile acid binders. Do not take if you have chronic liver disease, active peptic ulcer, or arterial bleeding. Use with great caution if you have gallbladder disease, diabetes, severe gout, or high blood levels of uric acid. Tests of blood glucose, uric acid, and liver functions need to be performed regularly.

*An asterisk indicates the drug is available in a generic version or is expected to be within the near future.


Nitrates

One of the oldest classes of drugs used to treat heart problems, nitrates (see Table 9) have been used for more than a century to treat angina. One common form, nitroglycerin (Nitrostat), is best known as the little white pills that people carry with them and slip under the tongue when they have bouts of chest pain. The drug also comes in different forms, including a short-acting liquid spray as well as long-acting ointments and patches. People who take the long-acting forms run the risk of developing nitrate tolerance, which means the body no longer responds to the drug’s effects. Removing the patch at night can minimize this risk.

Table 9: Nitroglycerin and long-acting nitrates

Generic name (brand name)

Side effects

Comments

nitroglycerin (Nitrostat)

Headache, flushing, low blood pressure.

Placed under tongue to provide relief from or to prevent angina attack; a short-acting preparation.

nitroglycerin spray (Nitrolingual Pump spray, NitroMist)

One to two squirts onto or under the tongue to treat or prevent angina.

isosorbide mononitrate* (Imdur, Ismo, others)

Long-acting nitrate pill; taken at regular prescribed intervals to decrease the frequency of angina.

nitroglycerin ointment (Nitro-Bid)

Placed on the skin and covered with a dressing, allowing slow absorption of the medication over several hours; removal of ointment for several hours each day recommended to provide a period without exposure to nitroglycerin.

nitroglycerin patch* (Minitran, Nitro-Dur, others)

Convenient; removal of patch for several hours each day recommended to provide a period without exposure to nitroglycerin.

Special caution for all nitrate medications: Do not use if you are taking medications to treat erectile dysfunction, such as tadalafil (Cialis), vardenafil (Levitra), or sildenafil (Viagra). These medications can cause a life-threatening drop in blood pressure when used in addition to a nitrate. If you are taking nitroglycerin and are experiencing erectile dysfunction, talk with your doctor about alternatives.

*An asterisk indicates the drug is available in a generic version or is expected to be within the near future.

Other nitrate delivery systems, including long-acting isosorbide mononitrates (Imdur, Ismo), accomplish the same thing with a single dose each day. One risk with this approach is that you might be left unprotected during the first hour or so after awakening—a high-risk time for heart attacks. This problem is often addressed by using other long-acting anti-anginal medications in conjunction with the nitrates.


Anticlotting medications

One goal of treatment is to prevent unwanted clots from forming, and for this, different types of drugs can be used (see Table 10).

Table 10: Anticlotting medications

Generic name (brand name)

Side effects

Comments

Anticoagulants

warfarin* (Coumadin, Jantoven)

Bleeding from any tissue or organ.

Not recommended for people who have active ulcers. Requires routine blood testing. Certain medications including antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), and barbiturates may boost the bleeding effect of warfarin.

dabigatran (Pradaxa)

Stomach pain, heartburn, nausea. Serious side effects include bleeding, joint pain or swelling, headache, swelling of the arms or lower legs.

Useful alternative to warfarin for people with atrial fibrillation who are at risk of stroke. Not for use in people with certain kidney diseases, liver disease, or a mechanical heart valve.

rivaroxaban (Xarelto)

Serious side effects include bleeding.

Also useful alternative to warfarin in people with atrial fibrillation at risk for stroke. Discontinuing rivaroxaban places patients at increased risk of forming a new blood clot. Not for use in people with reduced kidney or liver function, or those using medications that interfere with drug metabolism.

Platelet inhibitors

aspirin (Bayer, Anacin, others)

Bleeding in the gastrointestinal tract or brain.

Low-dose (81 mg) daily aspirin lowers risk of a repeat heart attack by about 25%.

clopidogrel* (Plavix)

Stomach pain, nausea, headache, dizziness. Serious side effects include bleeding, hives, rash, liver dysfunction, and swelling of the face, hands, and feet.

May be less effective in people taking heartburn drugs such as omeprazole (Prilosec) and esomeprazole (Nexium). About 3% of whites and blacks and up to 20% of East Asians have a genetic variation that diminishes the drug’s effectiveness. Genetic tests are available to identify people with this variant, and information about who should get this test should become available by 2012.

prasugrel (Effient)

Dizziness, excessive tiredness, headache, or pain in the back, arms, or legs. Serious side effects include shortness of breath and a slow, fast, or irregular heartbeat.

Should not be taken by people who have a history of ulcers or other internal bleeding, or who have had recent surgery, a stroke or a mini-stroke, or liver disease.

Glycoprotein IIb/IIIa inhibitors

abciximab (ReoPro)

Bleeding, dizziness, nausea, vomiting, headache, back pain, slow heart rate.

Unsafe for people with recent bleeding episodes or bleeding problems, who have had recent surgery, or who have had a stroke within two years.

eptifibatide (Integrilin)

Dosage should be monitored and adjusted carefully in people with kidney problems.

tirofiban (Aggrastat)

Unsafe for people with kidney problems.

*An asterisk indicates the drug is available in a generic version or is expected to be within the near future.

One class of anticlotting medications—known as anticoagulants, or “blood thinners”—reduces the activity of blood-borne proteins called clotting factors. This is the type of drug your doctor is likely to prescribe if you have atrial fibrillation, the most common cardiac arrhythmia and a leading cause of the clots that lead to strokes. The oldest drug of this class, warfarin (Coumadin, Jantoven), has been used by millions of people to lessen the chances of developing a harmful, or possibly fatal, blood clot. But many things can affect how the drug works, including what you eat and drink, your health, and a number of drugs, vitamins, supplements, and herbal remedies. As a result, people taking warfarin need routine blood tests of their international normalized ratio (INR), a measure of the time it takes blood to clot. The results tell your doctor if your warfarin dosage needs adjusting.

Two newer anticoagulants—dabigatran (Pradaxa) and rivaroxaban (Xarelto)—work in similar ways to warfarin but have several advantages. In clinical trials, these drugs decreased the risk of stroke or death more than warfarin, with fewer episodes of major bleeding. The drugs are not affected by diet and don’t require routine blood tests. But as with all newly approved drugs, the full extent of their efficacy, side effects, and safety won’t be apparent until after hundreds of thousands of people have taken them for long periods of time.

Another class of anticlotting medications is platelet inhibitors. As the name implies, these tamp down the activity of platelets rather than clotting factors. Aspirin is the best known platelet inhibitor. But in recent years, drugs called “super aspirins” have also become available, including clopidogrel (Plavix) and prasugrel (Effient). But because they’re more powerful than aspirin, these drugs are more likely to cause bleeding as well. If you have a newly implanted stent, your doctor may prescribe one of these drugs to prevent a clot forming on the stent.

A third class of anticlotting drugs is called glycoprotein IIb/IIIa inhibitors. These medications are given intravenously in the hospital to people who have unstable angina or who have had certain types of heart attacks, as well as those undergoing angioplasty or other invasive heart procedures.


Clot-busting medications

Your chances of surviving and recovering from a heart attack increase if you receive a clot-busting (thrombolytic) drug within 12 hours—and ideally within the first 90 minutes—after the heart attack starts. These medications, which are given through a vein, help restore blood flow by dissolving blood clots. Alteplase (Activase, or tPA) is the most common one; Table 11 lists additional options.

Table 11: Clot-busting medications

Generic name (brand name)

Side effects

Comments

recombinant tissue-plasminogen activator (t PA), also called alteplase (Activase)

Bleeding from any tissue or organ.

Must be given intravenously within a few hours of when heart attack symptoms begin. Can be life-threatening for people who have had a hemorrhagic stroke.

Unsafe for people who’ve had a previous stroke or head injury or who have uncontrolled hypertension, a bleeding disorder, an aneurysm, or an arteriovenous malformation.

reteplase (Retavase)

May be delivered via a catheter directly to the blood clot.

Unsafe for people who’ve had a previous stroke or head injury or who have uncontrolled hypertension or a bleeding disorder.

streptokinase (Streptase)

tenecteplase (TNKase)

urokinase (Abbokinase)

*An asterisk indicates the drug is available in a generic version or is expected to be within the near future.

Clot-busting drugs work by dissolving fibrin, the stringy protein that holds blood clots together. Because they increase the risk of bleeding, they shouldn’t be taken by people with certain health problems, including a history of hemorrhagic stroke (the type caused by bleeding rather than a clot); a head injury within the past three months; or major surgery, a major injury, or internal bleeding within the past month. People with stomach ulcers or severe high blood pressure shouldn’t take these drugs, either.


Combination medications

A number of combination drugs are available to treat coronary artery disease. Most aim to control high blood pressure by combining a diuretic with a beta blocker, calcium-channel blocker, ACE inhibitor, ARB, or a different type of diuretic. Other combination drugs help lower cholesterol.

Is a combination drug right for you? It depends on your situation. Many people take more than one drug to control blood pressure or cholesterol, for instance. If you find you routinely miss doses or get confused about which medications you have taken, it may make sense to take a combination pill.

Cost is another consideration, especially if you have to make a copayment each time you purchase a medication. Using a combination drug means you would make one copayment instead of two. But if you pay for your medication yourself, or if your health plan charges a higher copayment for brand-name drugs than for generics (as is often the case), a combination could prove more expensive, as some combination drugs include one or more brand-name drugs for which less expensive generic versions are available. Indeed, combination drugs represent a growth industry for drug makers: they can help a company extend high-profit sales of a drug whose patent is about to expire.

Using painkillers safely

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for relieving pain, reducing inflammation, and calming fevers. Some low-dose NSAIDs are available over the counter—for example, ibuprofen (Advil, Motrin) and naproxen (Aleve). Taken occasionally as directed, these medications are generally quite safe. But since NSAIDs were first introduced, some experts have expressed concerns that NSAIDs (particularly the high-dose prescription versions) might be risky for people with heart disease. This concern came to the fore in 2004 when the prescription NSAID rofecoxib (Vioxx) was found to increase the risk of heart attack and stroke. Vioxx and a related drug, Bextra, were taken off the market.

Since then, other studies have found that all existing NSAIDs except aspirin pose some risk for people with heart disease. A study published in The American Journal of Medicine in 2012 found that NSAIDs can raise blood pressure and interfere with blood pressure–lowering medications. And a 2012 report in Circulation found that among people who experienced a heart attack and regularly took NSAIDs after the attack, the risk of having a second heart attack increased by 41% over the next five years, and the risk of dying increased by 63% over the next five years.

The risk of heart attack and death with NSAIDs likely reflects the effect of these medications on blood cells involved in the formation of blood clots. Blood must maintain a constant balance between fluidity and clotting, and NSAIDs tip the balance toward clotting.

With NSAIDs widely used for relief of muscle and joint pain and inflammation, the need for guidance on the safest way to use these medications became clear. To educate prescribers and users, several major medical organizations formed the Alliance for Rational Use of NSAIDs (www.NSAIDAlliance.com). Their message is straightforward: take the lowest dose of NSAIDs for the shortest period of time needed to obtain relief.

Your should also try treating your pain with aspirin or acetaminophen (Tylenol) first. If these don’t control your pain, or if you need to control inflammation (for example, if you have arthritis or an injury), start with the least risky NSAID—naproxen—and move on to other NSAIDs only if it fails to work.

To further lower your risk, follow these tips:

  • Read the label on every drug you take to see whether it is an NSAID or contains an NSAID. This may prevent you from accidentally taking more than one NSAID, which would further raise your risk.

  • Before you take any NSAID, ask your doctor or pharmacist if there are any medications that should not be taken with it.

  • Learn the possible side effects of the NSAID you take.

  • Take the medication as directed.

  • Tell your doctor about over-the-counter drugs you take.

Another drawback to combination medications is that it is hard to adjust the dose, and changing dosages are a fact of life for people using cardiovascular drugs. Most people start on low doses of particular medications and then increase specific ones as needed to control one or more factors such as blood pressure, cholesterol, or blood sugar. But in a combination drug, the doses are paired: you can’t increase one medication without increasing the other.

For those reasons, combination drugs probably aren’t a good idea if you are just starting drug therapy. But if you have been taking two well-established medications at stable doses for some time, a combination that delivers both of them at the right doses is worth looking into, especially if it contains generic versions of the drugs.

With the help of medications and lifestyle changes, most people with coronary artery disease can live normal lives with few limitations. However, some people benefit from revascularization procedures, which restore blood flow to areas of the heart muscle that have been affected by the blocked artery. The two main procedures that are used to restore blood flow are angioplasty and coronary artery bypass surgery.

If your doctor has recommended a cardiac procedure, seek out a cardiac specialist at a medical center where bypass surgery and angioplasty are frequently performed. As you might expect, research has shown that outcomes are best at the institutions with the most experience. You may also want to do research about your surgeon’s track record (see “Report cards for cardiac surgery”). But in an emergency situation, the closest facility that performs the procedure is often your best option.


Angioplasty

Percutaneous transluminal coronary angioplasty (PTCA), better known as angioplasty, revolutionized cardiology. The technique enables doctors to open narrowed or blocked coronary arteries with special catheters that carry inflatable balloons. The term angioplasty refers to the reshaping of the narrowed segment of a blood vessel in the course of the procedure. Most angioplasty procedures also involve the placement of stents, which are metal mesh tubes that serve as scaffolds to help hold arteries open (see “How stents work”).

Angioplasty is usually the go-to treatment for stopping a heart attack. To be effective, angioplasty must be done early—ideally within 90 minutes of the start of symptoms, but certainly within 24 hours. Angioplasty can treat narrowing at curves in coronary arteries, disease in several vessels, and even narrowing in coronary artery bypass grafts. Because of technical advances in angioplasty, doctors are now willing to perform it on some people for whom it used to be considered too risky.

Angioplasty can also be used to alleviate angina. But it isn’t necessarily the first choice for treatment. And what if you have one or more narrowed coronary arteries that aren’t causing any symptoms at all? Angioplasty probably isn’t a good option, because it can’t make you feel any better. A major trial called Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) showed that medication plus lifestyle changes are a better treatment option for stable angina and narrowed coronary arteries that aren’t causing trouble.

And, contrary to what many people believe, angioplasty done for mild or no symptoms does not protect you from having a heart attack in the future. That’s because angioplasty does not solve the underlying problem of atherosclerosis. The procedure may open one or more narrowed arteries, but it is likely that troublesome atherosclerotic plaques lurk elsewhere. Even after people undergo angioplasty, they still have to take other steps to reduce their risk for heart attack, such as eating better, getting more exercise, and taking medications as prescribed. However, if you are having a heart attack or an episode of unstable angina, angioplasty is definitely better than drug treatment at preventing a second heart attack and improving survival.


What happens during angioplasty

A person undergoing angioplasty remains awake during the procedure, but receives local anesthesia. As in a routine coronary angiogram, angioplasty starts with the physician inserting a catheter into an artery in an arm or leg (see Figure 11) and guiding it through the blood vessels to the openings of the coronary arteries. Inside this catheter is a thinner catheter, which has an inflatable balloon near its tip. And inside that catheter is an even thinner wire with a soft tip that can snake through tight narrowings and punch through clots, but is unlikely to damage the wall of the coronary artery.

Figure 11: Radial artery angioplasty

image

Although most angioplasties are done via the femoral artery in the groin, a growing number are done through the radial artery in the wrist. A major study involving more than 7,000 patients in 32 countries found the two approaches to be nearly identical in terms of serious complications such as death or heart attack during the month following the procedure. But there were fewer cases of bleeding around the angioplasty entry site with the radial approach. And it also appeared to be more effective than the femoral approach for treating people in the midst of a heart attack, as reported in a 2011 study in The Lancet. Another advantage of the wrist entry: you don’t need to lie still for several hours after the procedure to make sure the bleeding has stopped.

Once the catheter reaches the heart, the cardiologist guides the wire gently down the artery until the tip is beyond the narrowing. (If the coronary artery is completely blocked, the physician may try to push the wire through the obstruction.) Once the wire has crossed the blockage, the catheter with the balloon slides down the wire until the balloon is next to the plaque (see Figure 12). From outside the body, the physician inflates the balloon, which cracks and compresses the atherosclerotic plaque, stretches the underlying normal artery wall, and widens the artery.

Figure 12: Balloon angioplasty

image

To open an artery narrowed by plaque, the interventional cardiologist feeds a catheter to the site of the blockage and threads a thin, flexible guide wire through the narrowing (A). The balloon catheter advances along the guide wire until it’s positioned directly inside the narrowed area (B). As the balloon inflates, it compresses the plaque, allowing freer passage of blood through the now-reopened artery (C). If a stent is being placed, inflation of the balloon expands the stent and pushes it into the walls of the artery.

Stent placement is also done with the balloon catheter. The stent is made of a springy, collapsible metal mesh, which is crimped onto the balloon catheter. When the balloon is inflated at the site of the blockage, the stent also expands. The doctor withdraws the catheter and the deflated balloon and leaves the expanded stent in place. Most stents are now coated with drugs to prevent cells lining the artery from growing over and around the stent and reblocking the vessel (see Figure 13).

Figure 13: Angioplasty with drug-coated stent

image

One way to prop open a blood vessel is to insert a mesh cage called a stent into the artery. But insertion of a stent can cause cells lining the artery, called endothelial cells, to begin growing over and around the struts of the stent, much like a plant might grow on a trellis. This growth, a process called restenosis (A), can gradually clog the stent. Using a stent coated with a drug that discourages this regrowth can help keep the stented artery clear (B).

Following stent placement, you will need to take medications to prevent the formation of a blood clot on or inside the stent. Aspirin must be taken indefinitely, no matter what type of stent is used. In addition, clopidogrel (Plavix) or prasugrel (Effient) must be taken for at least one month if an uncoated stent is inserted, and for at least one year if a drug-coated stent is used.

Even with the drug-coated stents, about five in 100 people will eventually need to repeat the procedure because the reopened artery narrows again. There are two main ways to tell if a stent has collapsed or if it is being overgrown with tissue: symptoms such as chest pain, and heart function tests. If you start experiencing chest pain or other symptoms of angina, call your cardiologist and ask for an evaluation. But if you feel fine, it is safe to assume that the stented artery remains open.

How stents work

Angioplasty has one troubling complication: restenosis, a renarrowing of an artery in the same spot that angioplasty had cleared. Restenosis usually happens within three to six months of the original procedure and may occur for several reasons. One cause is elastic recoil—that is, the vessel stretched by angioplasty gradually returns to its original size. A second reason is a vigorous growth of cells lining the vessel wall, which can form scar tissue as part of the healing process following angioplasty.

In the 1990s, cardiologists began using devices called stents to prop open arteries after angioplasty. A stent looks like a miniature chain-link fence rolled into a tube. By placing a stent inside the treated blood vessel, cardiologists were able to keep arteries from recoiling, thus preventing one serious complication of angioplasty. However, the early stents did not stop restenosis. Cells still grew in and around the stent.

Since then, drug-coated (also called drug-eluting) stents have helped to solve the problem. The earliest one, the Cypher stent, is coated with sirolimus, a substance that cools inflammation and stops muscle cells in the artery wall from growing and dividing. Trials comparing these stents with the older ones have shown a clear advantage for the sirolimus-coated stent. As of 2013, there were five drug-eluting stents on the market, featuring different but related drugs, and together these make up the majority of stents placed today.

But drug-coated stents have raised concerns of their own. The drugs they exude prevent cells in the artery wall from covering the stent. Without this protective sheath, clots can form on the stent, a process known as stent thrombosis. For this reason, anyone with a drug-eluting stent must also use a combination of two antiplatelet drugs for at least a year, while the bare-metal stents require dual antiplatelet therapy for only a few months.

At this writing, several companies are working on bioabsorbable stents, which would solve both stent problems. These experimental devices appear to hold open the artery for several months as natural healing takes place; then they are gradually broken down and absorbed by the body.


Complications from angioplasty

One possible complication of angioplasty is bleeding at the site in your leg or arm where catheter was inserted. Most of the time, this just causes a bruise, but sometimes serious bleeding occurs, which might require a blood transfusion or surgery. In addition, the blood clots that can occur during the procedure can trigger a minor heart attack in about four in 100 people, and a stroke in about one in 300 people. Overall, fewer than one in 100 people die from complications of angioplasty.

Other rare risks include damage to the coronary artery (such as a tear or rupture), which may require emergency surgery; kidney problems caused by the dye used during the procedure; and abnormal heart rhythms. The latter usually don’t last long, but some people need medications or a temporary pacemaker.


Coronary artery bypass surgery

The formal name for bypass surgery is coronary artery bypass grafting, sometimes referred to by its initials, CABG. It works by constructing a new channel so blood can get around blockages in the coronary arteries. A surgeon takes a length of blood vessel from elsewhere in the body and places it so that it can shunt blood around the narrowed or blocked coronary artery. The grafted vessel lets blood bypass the blockage, replenishing the heart muscle ordinarily supplied by that coronary artery.

Bypass surgery may be a better choice than angioplasty for people with blockages in multiple arteries. It also relieves the pain of angina more effectively on a long-term basis than angioplasty with or without stent insertion. One thing to keep in mind, however, is that bypass surgery does not cure the underlying disease—atherosclerosis—so angina may return five to 10 years after the operation, as arteries again become clogged with plaque. This is why it’s so important to exercise, follow a healthy diet, and take prescribed medications after bypass surgery.

Most bypass surgeries are conventional open-heart procedures (see “What happens during bypass surgery”). Two variations include beating-heart surgery (also called off-pump bypass) and minimally invasive bypass surgery. The procedure you undergo will depend on the nature and extent of your heart disease, your overall health, and your surgeon’s expertise.


What happens during bypass surgery

In most forms of bypass surgery, you receive general anesthesia. The surgeon cuts through your breastbone to reach your heart, which is stopped so that the surgeon doesn’t have to operate on a moving heart. A heart-lung machine pumps oxygen-rich blood through the body, temporarily substituting for the heart.

The surgeon takes a vein or an artery from another part of your body—either your chest, leg, or arm—and sews that vessel into place to reroute blood around the blocked artery. The surgeon will only take an artery or vein that is a “spare” vessel. You will suffer no ill effects from the removal of that piece of artery or vein.

If the grafted vessel is a vein from a leg or arm, one end is attached to the aorta and the other is sewn onto the diseased coronary artery, beyond the blockage. When a chest artery is used, the upper end is usually left in place at the aorta and the lower open end is attached to the diseased coronary artery, below the blockage. After the surgery is completed, your heart is started again, and you are taken off the heart-lung machine.

Some people stay in the hospital for just four to five days, but many stay six to 10 days or, if they have complications, even longer. Within a day or two of surgery, you’ll be encouraged to walk around. You might also be scheduled to start a cardiac rehabilitation program after leaving the hospital. Cardiac rehabilitation helps you and your heart gain strength. It also teaches you heart-healthy practices that will help protect you from future heart disease, such as following a low-fat diet and exercising regularly (see “Healing your heart: Cardiac rehabilitation”).

If your job doesn’t require much exertion, you can probably return to work in about two months. However, people who do heavy labor must wait longer or, in some cases, find jobs that aren’t as physically demanding.


Off-pump coronary artery bypass surgery

One less-invasive innovation in bypass surgery is a procedure called off-pump bypass, or beating-heart surgery, because the operating team doesn’t stop your heart and place you on a heart-lung machine. Instead, the surgeons use special equipment to hold the heart steady, letting them operate on it while it continues beating.

Early studies of the surgery, which was first introduced in the mid-1990s, suggested that off-pump bypass lowers the need for blood transfusions and leads to less short-term decline in memory and thinking skills. But more recent evidence hasn’t upheld that advantage. And some data show that grafts placed during off-pump surgery are more likely to become blocked, which probably reflects the technical difficulty of sewing grafts onto a beating heart.

Over all, in terms of effectiveness and safety, off-pump and conventional bypass surgery seem to be equal. The risks for two of the biggest long-term complications of bypass surgery, cardiac events (subsequent heart attack or the need for a follow-up procedure) and declines in memory and thinking skills, are similar for off-pump and conventional surgery. For now, the skill of the surgeon and the quality of the hospital are more likely to affect the outcome than whether your surgery is performed on-pump or off-pump.


Minimally invasive coronary artery bypass surgery

In minimally invasive coronary artery bypass surgery, the surgeon operates without making a large incision and splitting the breastbone, so recovery times are faster and risks are generally lower. This procedure can also be used either with or without the heart-lung machine. However, this procedure can only be used on people with one or two blocked arteries located at the front of the heart.

During the operation, the surgeon makes an incision of 2.5 to 4 inches on the left front side of the chest. To get to the heart, the surgeon separates the chest muscles and removes a small portion of the front of a rib. Usually a mechanical stabilizer steadies the heart, so that it continues beating while the surgeon performs the bypass operation. However, sometimes it is better to stop the heart. If a heart-lung machine is used, the surgeon operates with the help of a videoscope to see inside the unopened chest.

Compared with conventional bypass surgery, minimally invasive direct bypass causes less postoperative pain and reduces hospital stays to about three days on average. It is not yet known whether this procedure is as safe and effective (in both the short and long term) as conventional bypass surgery.


Keeping vessels clear after bypass surgery

Bypass surgery is very effective in controlling symptoms. Afterwards, people often feel as if they’ve been given a new lease on life. But, as is the case with angioplasty, bypass surgery doesn’t cure coronary artery disease. As a result, angina can recur, either from the buildup of plaque in arteries that weren’t bypassed or because blockages form in the grafts. Combating such problems requires dietary and lifestyle changes, such as exercising regularly and not smoking, as well as aggressive efforts to control cholesterol and blood pressure through medication. To maximize your chances of recovery, the experts recommend these steps:

Take a daily aspirin. You should begin taking a daily aspirin within 48 hours of your bypass operation in order to reduce the risk of your grafted vein closing, as well as to lower your chance of heart attack, stroke, kidney failure, or death. The dosage varies from 81 to 325 mg per day. If you are unable to tolerate or respond to aspirin, your doctor will recommend an alternative antiplatelet medication.

Use statin therapy. Almost everyone undergoing a bypass operation should take a statin to lower LDL cholesterol. If you cannot take a statin, work with your doctor to find another way to lower LDL. People undergoing a bypass operation should aim for LDL levels less than 70 mg/dL, based on recommendations by the National Cholesterol Education Program. Talk with your doctor to determine the LDL goal that will maximize your own recovery.

Treat all other risk factors. Even if your LDL levels are within the target range, you may also have to use medication and make lifestyle changes to boost your healthy HDL cholesterol level, lower harmful triglycerides, and control blood pressure and blood sugar.


Complications and risks of bypass surgery

Bypass surgery is recommended only for people who can’t be helped enough by heart medications or angioplasty, because it is riskier than these other treatments and requires a longer recovery time. Possible complications of conventional bypass surgery include heart attack, bleeding, and stroke. Stroke may occur if blood clots develop and travel to the brain, or if bleeding or periods of low blood pressure deprive the brain of oxygen during the surgery. About 3% to 5% of people who undergo bypass surgery have a stroke. About 5% suffer a heart attack. The risk for death from conventional bypass surgery is about 1% to 2%. Not surprisingly, these risks are lowest at hospitals that perform the most bypass operations. For the best results, find an experienced heart surgeon working at a hospital with a high-volume cardiac surgery unit.


Memory and concentration problems

Many people have mild memory problems or trouble concentrating following a bypass operation. Although the changes can be subtle, they’re often quite worrisome for patients. A frequently cited study found that about half of the people who underwent bypass surgery experienced memory impairment and thinking problems immediately afterward; about six months later, about one in four people continued to experience thinking problems.

Doctors once thought these problems resulted from using the heart-lung bypass machine. When blood passes through the heart-lung machine, it collects atherosclerotic particles and then deposits them in the brain. This may be true, but people who have off-pump bypass surgery also develop these mental problems, and at about the same rate.

On the other hand, the problem may not be the surgery. Some research has suggested that some of the biological processes involved in coronary artery disease also contribute to Alzheimer’s disease and other types of dementia—raising the possibility that it is the underlying disease, and not bypass surgery, that may contribute to problems with memory and thinking skills.

If you are preparing for a bypass operation, talk with your surgeon ahead of time about what strategies are available to minimize the chances of memory and thinking problems. After the operation, mention any issues that arise with attention or concentration.

Report cards for cardiac surgery

When choosing a surgeon to perform your upcoming coronary artery bypass, you probably want to know which surgeon has the lowest mortality rates. Some states, including New York, New Jersey, Pennsylvania, and Massachusetts, post report cards online that rate cardiac surgeons based on the outcomes of their patients.

While the report cards certainly merit a look, it’s important to keep a few precautions in mind. For one thing, the ratings are based on very small numbers. A busy cardiac surgeon may perform 200 bypass operations a year. The average death rate for bypass surgery is 2%. That means that a difference of one or two deaths in a year can make a good surgeon look bad. By the same token, a less experienced surgeon who performs fewer procedures a year may look very good. Mortality rates can also be skewed by how sick a patient was before the surgery. Surgeons who operate on sicker patients may end up looking bad, even if their surgical skills are excellent.

An important factor to consider when evaluating a surgeon is how many bypass procedures he or she performs every year. Choose a physician with more experience, especially if you have health issues that could cause problems during the surgery or recovery.

Finally, the quality of the hospital where you have your surgery is just as important as the quality of the surgeon. The best hospitals have key diagnostic tools, clear-cut safety systems to minimize medication mistakes and surgical errors, and a favorable nurse-to-patient ratio.


In conclusion: Living with coronary artery disease

A diagnosis of coronary artery disease is worrisome, but there are many steps you can take to reduce your risk of further cardiac problems, beginning with rigorous adherence to the drug regimen your doctor recommends. But while it’s tempting to rely solely on medications and surgical procedures, remember that the choices you make about day-to-day living—for example, going for an invigorating walk instead of sitting all day long, or cooking fish and a garden-fresh ratatouille for dinner instead of macaroni and cheese—can also make a surprising difference in the course of your disease. In fact, think of these lifestyle improvements as nature’s medicine chest because they work in so many different ways to help your body.

We won’t try to tell you that making all these changes is easy. But chances are that once you’re accustomed to a healthier lifestyle, you’ll feel so much better that it will inspire you to stick to your new habits—and help you maintain your well-being for years to come.


Organizations

American Association of Cardiovascular and Pulmonary Rehabilitation
330 N. Wabash Avenue, Suite 2000
Chicago, IL 60611
312-321-5146
www.aacvpr.org

Dedicated to reducing death and disability from heart and lung disease through education, rehabilitation, research, and disease management. The AACVPR certifies cardiac and pulmonary rehabilitation facilities to ensure they meet essential standards of care. The website includes a searchable directory of certified programs.

American Diabetes Association
1701 N. Beauregard St.
Alexandria, VA 22311
800-342-2383 (toll-free)
www.diabetes.org

Funds research into diabetes and serves as a prime resource for diabetes news, health information, legislative action, and advocacy efforts. Annual membership includes a subscription to the magazine Diabetes Forecast.

American Heart Association
7272 Greenville Ave.
Dallas, TX 75231
800-242-8721 (toll-free)
www.heart.org

Operates a consumer hotline to answer questions on general heart health, and offers educational pamphlets, posters, and audiovisual material, all at no charge or for a nominal fee. Its website has news on heart disease research, as well as background information on prevention and treatments.

Million Hearts Initiative
millionhearts.hhs.gov

This national initiative, launched by the Department of Health and Human Services in 2011, aims to prevent one million heart attacks and strokes by 2017. The coalition of programs, policies, and campaigns aim to promote heart health by emphasizing the ABCS (aspirin therapy, blood pressure control, cholesterol management, and smoking cessation).

National Heart, Lung, and Blood Institute
NHLBI Health Information Center
P.O. Box 30105
Bethesda, MD 20824
301-592-8573
www.nhlbi.nih.gov

Offers educational pamphlets on heart disease, blood pressure, cholesterol, obesity, and physical activity at no charge or for a nominal fee. These pamphlets are available on the website, or you can order them by phone.


Special Health Reports

To order these or other Harvard Medical School publications, go to www.health.harvard.edu or phone 877-649-9457 (toll-free).

Healthy Eating for a Healthy Heart
Dariush Mozaffarian, MD, and Ellen di Bonaventura, MS, RD, Medical Editors
(Harvard Medical School, 2011)

This 49-page in-depth report helps you to consider the types
of foods that you eat and your overall dietary pattern to improve your heart health.

Hypertension: Controlling the “Silent Killer”
Randall M. Zusman, MD, Medical Editor
(Harvard Medical School, 2010)

Learn how to cut excess salt from your diet, use a home blood pressure monitor, and choose a drug treatment strategy based on your age and any other existing medical issues you may have.

What to Do About High Cholesterol
Mason W. Freeman, MD, Medical Editor
(Harvard Medical School, 2012)

Gain a better understanding of cholesterol tests, the genetics of cholesterol, and treatments based on the latest scientific evidence, and learn how to work with your doctor to individualize your treatment.


Newsletter

Harvard Heart Letter
Harvard Medical School
P.O. Box 9308
Big Sandy, TX 75755

Edited by Harvard Medical School cardiologist Deepak L. Bhatt, MD, MPH, this monthly newsletter provides timely, practical information on heart health. To order, go to www.health.harvard.edu or phone 877-649-9457 (toll-free).

angina: Chest pain or discomfort that develops when the heart muscle isn’t getting enough oxygen and blood.

angioplasty: A procedure in which a catheter with a deflated balloon at the tip is threaded into the heart through a blood vessel in the groin or wrist. The balloon then inflates to open up the blockage in a coronary artery.

atherosclerosis: The buildup of fatty deposits in the walls of arteries; the disease responsible for most heart attacks and many strokes.

cardiac catheterization: A procedure in which a catheter is inserted into a coronary artery.

cardiovascular disease: A broad term for heart disease, including coronary artery disease, heart failure, stroke, and hypertension.

catheter: A thin, flexible tube that is inserted into the body.

cholesterol: A waxy, fatlike substance that is present in animal tissues and produced by the liver. Excess levels can build up in artery walls.

coronary angiogram: A test that involves putting a catheter into a blood vessel in the groin or wrist, threading it up to the coronary arteries, and injecting a dye that can be seen on an x-ray. The x-ray then shows if (and how severely) the coronary arteries are narrowed.

coronary arteries: The small blood vessels that carry oxygen-rich blood to the heart muscle.

coronary artery bypass graft: A surgical procedure that uses a blood vessel taken from a person’s leg, arm, or chest and moves it to reroute blood around a clogged coronary artery; also known by its acronym, CABG (pronounced “cabbage”).

coronary artery disease: The most important form of heart disease, caused by the buildup of fatty plaques in the coronary arteries.

diastolic blood pressure: The pressure in the arteries while the heart is refilling with blood between beats; the second and lower of the two numbers obtained when blood pressure is measured.

echocardiogram: An imaging test that uses sound waves to create still and moving pictures of the heart that show its size, shape, and structure and how well it is functioning.

electrocardiogram (ECG): A graph recording the electrical activity responsible for the contraction and relaxation of the heart.

heart attack: Damage to, or death of, heart muscle because of insufficient blood supply; the medical term is myocardial infarction.

high blood pressure: A longstanding increase in blood pressure above the normal range—that is, abnormally high pressure of blood flow against the artery walls; also called hypertension.

high-density lipoprotein (HDL): A lipoprotein that transports cholesterol from body cells to the liver and other sites for elimination; called “good” cholesterol.

lipoprotein: A combination of fat (lipid) molecules and protein molecules bound together as packages that enable other fats and cholesterol to move easily through the blood. See low-density lipoprotein and high-density lipoprotein.

low-density lipoprotein (LDL): Spherical particles that transport cholesterol in the blood; called “bad” cholesterol because high levels are associated with a high risk for heart attack.

myocardial infarction: Heart attack.

plaque: Deposits of cholesterol and fatty and fibrous substances in the walls of the arteries.

platelets: Small, fragmentary blood cells that initiate the clotting process.

prehypertension: A condition that increases the risk of developing high blood pressure; defined as systolic pressure between 120 and 139 mm Hg or diastolic pressure between 80 and 89 mm Hg.

restenosis: Renarrowing of a blood vessel that has been widened (with or without a stent) during angioplasty.

stable angina: Chest pain brought on by exertion or stress that lasts just a few minutes and goes away quickly when you rest or take medication.

stent: A wire mesh device inserted into a coronary artery to prop it open once a blockage has been cleared by angioplasty.

systolic blood pressure: The pressure in the arteries at the point when the heart pumps; the first and higher of the two numbers obtained when blood pressure is measured.

triglycerides: Particles that transport fats through the bloodstream.

unstable angina: Chest pain that happens unexpectedly, usually during rest, and that lasts several minutes to several hours.

Medical Editor
Peter H. Stone, MD
Professor of Medicine, Harvard Medical School
Senior Physician, Brigham and Women’s Hospital
Director of Vascular Profiling Research Group
Cardiovascular Division, Brigham and Women’s Hospital

Executive Editor
Anne Underwood

Writer
Julie Corliss

Copy Editor
Robin Netherton

Creative Director
Judi Crouse

Production Manager
Lori Wendin

Illustrators
Scott Leighton
Michael Linkinhoker

Published by Harvard Medical School
Anthony L. Komaroff, MD, Editor in Chief
Patrick J. Skerrett, Executive Editor

In association with Belvoir Media Group, LLC
Robert Englander, Chairman and CEO
Timothy H. Cole, Executive Vice President and Editorial Director

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natalie_ramm@hms.harvard.edu

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For the latest information and most up-to-date publication list, visit us online at www.health.harvard.edu

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