Heart Disease page 3 Prevention, Diagnosis and Treatment

As these descriptions of the various forms of heart disease indicate, much is known about the causes, often referred to as “risk factors.” Some—such as heredity, age, race, and gender—cannot be controlled. But many others are controllable and there are many ways you can prevent heart disease.

Basically, heart disease prevention falls into two categories: lifestyle or behavior modification; and pharmacological intervention, or use of medications.

Lifestyle

Cigarette Smoking. The single most important thing you can do to prevent heart disease is not smoke. If you do smoke, you should stop; your risk of heart disease will begin to decline, reaching the level of a non-smoker after 5 to 10 years.

The higher risk of cardiovascular disease in women due to smoking is similar to that of men. Low tar and low nicotine cigarettes seem to be no less harmful than regular cigarettes. A range of studies has shown that women who smoke are from 2 to 6 times more likely than non-smokers to develop heart disease. Statistics from the Nurses' Health Study, a large, ongoing survey of women's health, show that half of the cases of heart disease in women aged 30 to 55 can be linked to cigarette smoking.

The most dramatic increase in risk is in women who smoke and use oral contraceptives. Tests have shown that these women are 20 to 30 times more likely to suffer heart disease and stroke than women who do neither. However, most of the data on this subject came from studies done when participants were taking a much higher dose of estrogen than is currently prescribed. As a result, further research is needed on the effects of today's lower-dose oral contraceptives.

Cigarettes act in a number of ways to increase your risk of heart disease. Smoking causes thickening of the blood, which can lead to clots. It raises the level of carbon monoxide in the blood, robbing the heart and other tissues of needed oxygen. The nicotine in tobacco also constricts the coronary arteries, raising blood pressure, and causing the heart to work harder. Thus smoking increases the amount of oxygen that the heart needs, while at the same time decreasing the amount it gets.

High blood pressure contributes to heart disease because it makes the heart work harder. Controllable factors that contribute to high blood pressure include overweight, lack of exercise, excessive salt intake, and cigarette smoking. It follows logically that losing weight, exercising, limiting salt in your diet, and stopping smoking can reduce blood pressure to healthier levels. Living with continually high levels of stress is also linked to high blood pressure.

The first thing you can do to control your blood pressure is to know what it is. Although you can measure blood pressure with a sphygmomanometer at the supermarket or shopping mall, it is a good idea to discuss the implications of your blood pressure level with your doctor.

Cholesterol, a very popular topic these days, is a substance that circulates in the blood, and is essential for functions such as producing some hormones (including estrogens) and building a protective membrane for our cells. We get some from what we eat, but mostly it is manufactured in the liver.

Cholesterol travels through the bloodstream attached to lipoproteins, compounds composed of fats (lipids), proteins, and triglycerides. There are four kinds of lipoproteins, classified according to their weights: very low density (VLDL), low density (LDL), high density (HDL) and very high density (VHDL). You've probably heard about “good” and “bad” cholesterol. The good is HDL, which is associated with a cleansing effect in the blood; and the bad is LDL, which leaves deposits on the interior walls of the arteries, hampering the flow of blood and leading to atherosclerosis.

In general, a total cholesterol count of less than 200 milligrams per deciliter of blood is viewed as healthy; if that count reaches 240, the risk of heart disease doubles. However, most of the studies that have drawn this conclusion have been done on men. One study focusing on women has found that the most important factor predicting coronary artery disease in women is not total cholesterol, but the ratio of HDL to total cholesterol: The higher your HDL, the less likely you are to get heart disease.

Triglycerides are another kind of fat in your bloodstream, but elevated triglycerides are not necessarily associated with an increased risk of heart disease. Triglyceride levels fluctuate widely throughout the day, depending on what you eat. They may, however, be associated with high cholesterol levels.

You can do a great deal to achieve a healthier cholesterol level by controlling your diet. Reducing cholesterol and fat intake, particularly saturated fats, will lower total cholesterol levels. Monounsaturated fatty acids (such as those found in olive and canola oil) tend to raise HDL, so those are the healthiest oils to choose for cooking. Polysaturated oils (safflower, corn) lower LDL, which is good, but also lower HDL. The worst offenders are the saturated fats (meat fat, butter), which raise LDL, lower HDL, and also include cholesterol itself. (For more information, turn to chapter 15, “A Common­Sense Look at Diet and Health.”)

Diet is not the only thing that affects your cholesterol level; other factors include heredity, smoking, and hormones. Estrogen plays an important role in keeping cholesterol levels down, and the hormonal changes of menopause will adversely affect your LDL and HDL counts.

Exercise and weight. Lack of exercise has been shown to be a risk factor for heart disease. Regular aerobic exercise seems to tone the heart muscle and help prevent heart disease. Again, most of the studies about exercise and heart disease have been done on men, but the effects are thought to be similar in women. Strenuous athletics are not necessary; moderate exercise such as brisk walking or stair­ climbing are sufficient to benefit the heart.

Exercise also lowers cholesterol and blood pressure and is usually associated with weight loss. Being overweight also contributes to high cholesterol and high blood pressure, both factors in developing heart disease.

Body shape is another risk factor for heart disease. Women with “apple-shaped” bodies—more weight around the waistline—have a greater risk than “pear-shaped” women who carry most of their weight around their hips.

Women, especially those who have already suffered heart disease and those with high risk factors, should know that although the benefits of exercise usually outweigh the risks, there is a slight chance that strenuous exercise can contribute to heart attacks, strokes, and arrhythmias. You should plan and discuss any exercise program with your doctor, particularly if you have not been physically active for a while.

Alcohol consumption. The effect of alcohol on heart disease is a very controver-sial subject. On one hand, there is plenty of documentation of the negative effects of excessive drinking on not just the heart, but a number of body systems. On the other, a number of tests in recent years have indicated that moderate drinking (1 or 2 drinks a day) may protect against heart disease.

The American Heart Association has addressed this issue by advising that drinking is safe only in moderation; and that if you don't already drink, there really is no benefit to starting.

Social and psychological factors. It was once speculated that as women entered the workforce in increasing numbers and began experiencing the same workplace stresses as men, heart attack rates in middle-aged women would begin to approach those of their male counterparts. That has not happened. Women working outside the home have about the same rates of heart disease as women who don't. Twenty years of research in the Framingham study found that employment itself is not predictive of heart disease, but factors such as high demands and low control of the situation, as well as financial anxiety, are related to higher rates of heart disease.

In men, heart disease has been linked to the so-called “Type A” personality, the impatient, driven, competitive personality type. No similar link has been found in women. In fact, Framingham data have shown that women who suppress anger and hostility are more likely to suffer heart disease than those who express it in the Type A manner. Having depression or anxiety is also linked to increased rates of heart disease in women.

Research over the last 10 years has consistently found that heart disease occurs more frequently in less educated women in lower socioeconomic groups than in better educated women in higher socioeconomic groups. The reasons for this are probably related to a number of factors including poorer health care, lack of health insurance, gender discrimination, and increased stress.

Drugs

A number of different drugs can also play an important role in preventing heart disease.

Aspirin has received a lot of attention since several studies found that, in small daily doses, it helps prevent heart attacks. Unfortunately, the tests that turned up these results were done only on men, and it is not known whether the findings are applicable to women. Preliminary studies of women's use of aspirin seems to suggest that a similar protective factor may be found. Aspirin is thought to lower heart attack risk because of its blood-thinning effects. But more research is needed before aspirin's benefits for women are fully defined.

Since some women should not take aspirin because of other medical conditions (for example, clotting disorders), and because dosing is different for preventive therapy than it is for headaches or other common uses, you should consult your physician before taking aspirin to prevent heart disease.

Hormone replacement therapy has become one of the most controversial areas of women's health. When you pass through menopause, your body produces ever decreasing amounts of estrogen. And since it is after menopause that heart disease rates in women rise towards those in men, natural estrogen depletion is thought to be a major factor. (Although not the only one: Some scientists are testing the hypothesis that iron loss during menstruation also helps protect against heart disease.)

Many studies have found that women on estrogen replacement therapy during and after menopause have a lower risk of heart disease. However, the subject is still controversial because replacing estrogen also increases the risk of other diseases, particularly endometrial cancer and possibly breast cancer. The therapy has evolved over the years, and most women on hormone replacement therapy now receive a combination of estrogen and progestin, a hormone that prevents endometrial cancer. However, not much is known about whether the addition of progestin decreases estrogen's heart benefits, and a number of studies are only now underway to test that effect.

The drugs used for hormone replacement therapy are the same as those in oral contraceptives, except at much lower doses; and combining oral contraceptives and cigarette smoking compounds the risk of heart disease. It's not known whether smoking has the same effect during hormone replacement therapy. This is another area that needs further investigation. For more on the hormone replacement controversy, see chapter 31, “Hormone Replacement Therapy: Weighing the Pros and Cons.”

High blood pressure medications are available in great variety if diet and behavior changes are not effective. There are five major types:

• Diuretics, which reduce the amount of salt and fluid in the bloodstream, in turn reducing blood pressure.
• Beta blockers, which reduce the force and speed of the heart's pumping action.
• ACE inhibitors, which reduce the level of angiotensin, a chemical that the body produces to raise blood pressure.
• Calcium channel blockers, which relax the arteries and reduce resistance to bloodflow.
• Vasodilators and alpha adrenergic blocking agents, which also relax the arteries.

Cholesterol lowering drugs work in several ways: They prevent the body from producing cholesterol, reduce the absorption of the cholesterol that you consume, or combine with cholesterol to remove it from the bloodstream. Some of the drugs that are used include niacin, lovastatin (Mevacor), cholestryamine (Questran), gemfibrozil (Lopid), and probucol (Lorelco).

Vitamin E, in early studies of women, has shown promising effects on the heart. Taken for a sustained period of time at high enough levels, it seems to lower the risk of heart disease. However, researchers are unwilling to make a firm recommendation until additional evidence is in.

How To Diagnose The Disease

Return to top

A lot of attention is given to many of the “miracle” drugs offered by modern science. Equally impressive are some of the diagnostic tools that have been developed to detect heart disease, so that it can be appropriately treated and controlled.

Diagnostic procedures range from non­ invasive tests done outside the body to invasive probes into the circulatory system. Often, positive findings on non­ invasive tests like the electrocardiogram or treadmill test signal the need for more invasive procedures.

Electrocardiogram

The electrocardiogram (known popularly as the ECG or EKG) is a graphic representation of the electrical currents that run through the heart as it pumps. The ECG can be taken while you are resting or exercising (usually on a treadmill), and the only discomfort you might experience is several small electrodes attached to your skin.

Normal ECG readings in women during exercise are likely to mean that no heart disease is present; and—compared with men—abnormal readings are much more likely to be false positives; that is, not truly a sign of heart disease. One study found false positives in only 8 percent of the men tested and a whopping 67 percent of women undergoing the same test. In other words, even if stress testing is positive, there's still an excellent chance that your heart is healthy. Some doctors skip the stress test altogether, especially in a patient with clear physical symptoms (such as repeated incidents of angina), and move directly to more specific testing.

Radionuclide Studies

These studies follow radioactive substances that have been injected into the bloodstream. One common example, exercise thallium scintigraphy, uses computer imaging to track an injection of radioactive thallium through the bloodstream and assess bloodflow to the heart during exercise. This test also turns up many false positives in women because breast tissue can create a shadow that looks like a blockage. Another form of radionuclide testing is used for women who are unable to exercise strenuously enough for exercise testing. The drugs used in these tests, dipyridamole (Persantine IV) or adenosine (Adenocard), mimic the effects of exercising.

Echocardiogram

Echocardiography is a diagnostic method that measures ultrasound waves. The waves are transmitted into the body, and the echoes that come back from the heart's surface are transformed into a video picture showing the size, shape, and movement of the heart. Like radionuclide studies, echocardiography can be combined with exercise or drug­induced stress to study the heart and blood flow under stress conditions. Dobutamine (Dobutrex) can be administered during echocardiography to simulate the effects of exercise on the heart. Doctors frequently use echocardiography to confirm a suspicion of mitral valve prolapse and other valvular disorders.

Angiogram

Angiography is a way of seeing the interior of the heart and blood vessels. In a procedure more invasive than electro­ or echocardiography, a catheter (a long, flexible tube) is inserted into a large blood vessel, usually the femoral artery in the upper thigh, and threaded up to the heart in a procedure called cardiac catheterization. Contrasting die is injected through the catheter, allowing x­rays of the heart and blood vessels that can show the degree of blockage.

The angiogram is probably the most definitive tool for diagnosing heart disease, but because it carries a small risk of injury or death, it is not routinely prescribed. One of the controversies about women's health care focuses on the angiogram, which is ordered much less frequently for women than for men. One study found that 10 times as many men as women (40 percent, compared to 4 percent) were referred for an angiogram after a positive ECG stress test. This is partly because of the known high number of false positives in women's stress ECGs, but it may also reflect a pervasive pattern of less aggressive treatment of heart disease in women. Many physicians treating women with heart disease believe that this pattern is changing as the medical profession and women themselves become more aware of the true risk of serious heart disease.

Treatment Options Today

Return to top

As with most other diseases, there is a broad range of treatments available for heart disease, proceeding from the minimum—lifestyle and behavior changes—to the maximum—heart transplant. Lifestyle changes to treat heart disease parallel those to prevent it. A primary difference is that if you already have heart disease, you should consult closely with your doctor as you consider which changes will be most appropriate.

There are, of course, many intermediate steps between simple lifestyle changes and heart transplant. These include a variety of drug therapies; angioplasty, in which arteries are widened with the insertion of a balloon; and several different surgical procedures including valve replacement and bypass operations.

Heart disease is really a variety of diseases that strike different parts of the circulatory system and act in different ways. They are progressive, interrelated conditions, and treatment of one problem early in the continuum—for example, coronary artery disease—can prevent more serious consequences such as heart attack.

Obviously, there is no single treatment. And there are no definitive solutions to the problem of determining which therapies—most of which have been tested primarily on men—will work best for women. But understanding the available options is an important first step in deciding, with your doctor, which treatment is best for you.

Drugs

Drugs have been used to treat heart disease for centuries. There's a wide variety; and they work in a variety of ways. Little is known about whether heart medications affect women differently than men. But so far, indications are that the drug's effects are similar, regardless of gender, although the most effective dosage levels may vary.

Digitalis. Two hundred years ago a British physician discovered that digitalis, an extract from the foxglove plant commonly grown in English gardens, strengthens the contraction of the heart muscle. This drug is still used to treat congestive heart failure, and is also useful in correcting irregular heartbeats.

Nitroglycerin. Nearly a century later, a Scottish medical student theorized that amyl nitrite, known to relax the capillaries, could relieve the pain of angina by increasing blood flow to the heart. A form of that drug, nitroglycerin, is still widely used for this purpose.

Beta blockers, often used to treat high blood pressure, are among the most valuable drugs used to treat the heart. They act to block the activity of the beta-adrenergic system, a highly integrated nerve and hormonal system that affects the heart's rhythm and strength of contractions, among other things. Propranolol (Inderal), the first and most widely used of the beta blockers, has been found effective for treating angina, high blood pressure, and migraine headaches. This, and related drugs, are also effective in preventing second heart attacks.

PUTTING THE PRESSURE ON PLAQUE

For many people with clogged coronary arteries, angioplasty now provides a less traumatic alternative to traditional bypass surgery. During this newer procedure, a balloon-tipped catheter is threaded up through the circulatory system until it reaches the diseased artery, then inflated to squeeze back the encroaching plaque. Often the balloon is surrounded by a collapsible mesh tube called a stent. When the expanded stent has been lodged firmly against the plaque, the balloon is deflated and withdrawn.

How To Stave Off Disease

As these descriptions of the various forms of heart disease indicate, much is known about the causes, often referred to as “risk factors.” Some—such as heredity, age, race, and gender—cannot be controlled. But many others are controllable and there are many ways you can prevent heart disease.

Basically, heart disease prevention falls into two categories: lifestyle or behavior modification; and pharmacological intervention, or use of medications.

Lifestyle

Cigarette Smoking. The single most important thing you can do to prevent heart disease is not smoke. If you do smoke, you should stop; your risk of heart disease will begin to decline, reaching the level of a non-smoker after 5 to 10 years.

The higher risk of cardiovascular disease in women due to smoking is similar to that of men. Low tar and low nicotine cigarettes seem to be no less harmful than regular cigarettes. A range of studies has shown that women who smoke are from 2 to 6 times more likely than non-smokers to develop heart disease. Statistics from the Nurses' Health Study, a large, ongoing survey of women's health, show that half of the cases of heart disease in women aged 30 to 55 can be linked to cigarette smoking.

The most dramatic increase in risk is in women who smoke and use oral contraceptives. Tests have shown that these women are 20 to 30 times more likely to suffer heart disease and stroke than women who do neither. However, most of the data on this subject came from studies done when participants were taking a much higher dose of estrogen than is currently prescribed. As a result, further research is needed on the effects of today's lower-dose oral contraceptives.

Cigarettes act in a number of ways to increase your risk of heart disease. Smoking causes thickening of the blood, which can lead to clots. It raises the level of carbon monoxide in the blood, robbing the heart and other tissues of needed oxygen. The nicotine in tobacco also constricts the coronary arteries, raising blood pressure, and causing the heart to work harder. Thus smoking increases the amount of oxygen that the heart needs, while at the same time decreasing the amount it gets.

High blood pressure contributes to heart disease because it makes the heart work harder. Controllable factors that contribute to high blood pressure include overweight, lack of exercise, excessive salt intake, and cigarette smoking. It follows logically that losing weight, exercising, limiting salt in your diet, and stopping smoking can reduce blood pressure to healthier levels. Living with continually high levels of stress is also linked to high blood pressure.

The first thing you can do to control your blood pressure is to know what it is. Although you can measure blood pressure with a sphygmomanometer at the supermarket or shopping mall, it is a good idea to discuss the implications of your blood pressure level with your doctor.

Cholesterol, a very popular topic these days, is a substance that circulates in the blood, and is essential for functions such as producing some hormones (including estrogens) and building a protective membrane for our cells. We get some from what we eat, but mostly it is manufactured in the liver.

Cholesterol travels through the bloodstream attached to lipoproteins, compounds composed of fats (lipids), proteins, and triglycerides. There are four kinds of lipoproteins, classified according to their weights: very low density (VLDL), low density (LDL), high density (HDL) and very high density (VHDL). You've probably heard about “good” and “bad” cholesterol. The good is HDL, which is associated with a cleansing effect in the blood; and the bad is LDL, which leaves deposits on the interior walls of the arteries, hampering the flow of blood and leading to atherosclerosis.

In general, a total cholesterol count of less than 200 milligrams per deciliter of blood is viewed as healthy; if that count reaches 240, the risk of heart disease doubles. However, most of the studies that have drawn this conclusion have been done on men. One study focusing on women has found that the most important factor predicting coronary artery disease in women is not total cholesterol, but the ratio of HDL to total cholesterol: The higher your HDL, the less likely you are to get heart disease.

Triglycerides are another kind of fat in your bloodstream, but elevated triglycerides are not necessarily associated with an increased risk of heart disease. Triglyceride levels fluctuate widely throughout the day, depending on what you eat. They may, however, be associated with high cholesterol levels.

You can do a great deal to achieve a healthier cholesterol level by controlling your diet. Reducing cholesterol and fat intake, particularly saturated fats, will lower total cholesterol levels. Monounsaturated fatty acids (such as those found in olive and canola oil) tend to raise HDL, so those are the healthiest oils to choose for cooking. Polysaturated oils (safflower, corn) lower LDL, which is good, but also lower HDL. The worst offenders are the saturated fats (meat fat, butter), which raise LDL, lower HDL, and also include cholesterol itself. (For more information, turn to chapter 15, “A Common­Sense Look at Diet and Health.”)

Diet is not the only thing that affects your cholesterol level; other factors include heredity, smoking, and hormones. Estrogen plays an important role in keeping cholesterol levels down, and the hormonal changes of menopause will adversely affect your LDL and HDL counts.

Exercise and weight. Lack of exercise has been shown to be a risk factor for heart disease. Regular aerobic exercise seems to tone the heart muscle and help prevent heart disease. Again, most of the studies about exercise and heart disease have been done on men, but the effects are thought to be similar in women. Strenuous athletics are not necessary; moderate exercise such as brisk walking or stair­ climbing are sufficient to benefit the heart.

Exercise also lowers cholesterol and blood pressure and is usually associated with weight loss. Being overweight also contributes to high cholesterol and high blood pressure, both factors in developing heart disease.

Body shape is another risk factor for heart disease. Women with “apple-shaped” bodies—more weight around the waistline—have a greater risk than “pear-shaped” women who carry most of their weight around their hips.

Women, especially those who have already suffered heart disease and those with high risk factors, should know that although the benefits of exercise usually outweigh the risks, there is a slight chance that strenuous exercise can contribute to heart attacks, strokes, and arrhythmias. You should plan and discuss any exercise program with your doctor, particularly if you have not been physically active for a while.

Alcohol consumption. The effect of alcohol on heart disease is a very controver-sial subject. On one hand, there is plenty of documentation of the negative effects of excessive drinking on not just the heart, but a number of body systems. On the other, a number of tests in recent years have indicated that moderate drinking (1 or 2 drinks a day) may protect against heart disease.

The American Heart Association has addressed this issue by advising that drinking is safe only in moderation; and that if you don't already drink, there really is no benefit to starting.

Social and psychological factors. It was once speculated that as women entered the workforce in increasing numbers and began experiencing the same workplace stresses as men, heart attack rates in middle-aged women would begin to approach those of their male counterparts. That has not happened. Women working outside the home have about the same rates of heart disease as women who don't. Twenty years of research in the Framingham study found that employment itself is not predictive of heart disease, but factors such as high demands and low control of the situation, as well as financial anxiety, are related to higher rates of heart disease.

In men, heart disease has been linked to the so-called “Type A” personality, the impatient, driven, competitive personality type. No similar link has been found in women. In fact, Framingham data have shown that women who suppress anger and hostility are more likely to suffer heart disease than those who express it in the Type A manner. Having depression or anxiety is also linked to increased rates of heart disease in women.

Research over the last 10 years has consistently found that heart disease occurs more frequently in less educated women in lower socioeconomic groups than in better educated women in higher socioeconomic groups. The reasons for this are probably related to a number of factors including poorer health care, lack of health insurance, gender discrimination, and increased stress.

Drugs

A number of different drugs can also play an important role in preventing heart disease.

Aspirin has received a lot of attention since several studies found that, in small daily doses, it helps prevent heart attacks. Unfortunately, the tests that turned up these results were done only on men, and it is not known whether the findings are applicable to women. Preliminary studies of women's use of aspirin seems to suggest that a similar protective factor may be found. Aspirin is thought to lower heart attack risk because of its blood-thinning effects. But more research is needed before aspirin's benefits for women are fully defined.

Since some women should not take aspirin because of other medical conditions (for example, clotting disorders), and because dosing is different for preventive therapy than it is for headaches or other common uses, you should consult your physician before taking aspirin to prevent heart disease.

Hormone replacement therapy has become one of the most controversial areas of women's health. When you pass through menopause, your body produces ever decreasing amounts of estrogen. And since it is after menopause that heart disease rates in women rise towards those in men, natural estrogen depletion is thought to be a major factor. (Although not the only one: Some scientists are testing the hypothesis that iron loss during menstruation also helps protect against heart disease.)

Many studies have found that women on estrogen replacement therapy during and after menopause have a lower risk of heart disease. However, the subject is still controversial because replacing estrogen also increases the risk of other diseases, particularly endometrial cancer and possibly breast cancer. The therapy has evolved over the years, and most women on hormone replacement therapy now receive a combination of estrogen and progestin, a hormone that prevents endometrial cancer. However, not much is known about whether the addition of progestin decreases estrogen's heart benefits, and a number of studies are only now underway to test that effect.

The drugs used for hormone replacement therapy are the same as those in oral contraceptives, except at much lower doses; and combining oral contraceptives and cigarette smoking compounds the risk of heart disease. It's not known whether smoking has the same effect during hormone replacement therapy. This is another area that needs further investigation. For more on the hormone replacement controversy, see chapter 31, “Hormone Replacement Therapy: Weighing the Pros and Cons.”

High blood pressure medications are available in great variety if diet and behavior changes are not effective. There are five major types:

• Diuretics, which reduce the amount of salt and fluid in the bloodstream, in turn reducing blood pressure.
• Beta blockers, which reduce the force and speed of the heart's pumping action.
• ACE inhibitors, which reduce the level of angiotensin, a chemical that the body produces to raise blood pressure.
• Calcium channel blockers, which relax the arteries and reduce resistance to bloodflow.
• Vasodilators and alpha adrenergic blocking agents, which also relax the arteries.

Cholesterol lowering drugs work in several ways: They prevent the body from producing cholesterol, reduce the absorption of the cholesterol that you consume, or combine with cholesterol to remove it from the bloodstream. Some of the drugs that are used include niacin, lovastatin (Mevacor), cholestryamine (Questran), gemfibrozil (Lopid), and probucol (Lorelco).

Vitamin E, in early studies of women, has shown promising effects on the heart. Taken for a sustained period of time at high enough levels, it seems to lower the risk of heart disease. However, researchers are unwilling to make a firm recommendation until additional evidence is in.

How To Diagnose The Disease

Return to top

A lot of attention is given to many of the “miracle” drugs offered by modern science. Equally impressive are some of the diagnostic tools that have been developed to detect heart disease, so that it can be appropriately treated and controlled.

Diagnostic procedures range from non­ invasive tests done outside the body to invasive probes into the circulatory system. Often, positive findings on non­ invasive tests like the electrocardiogram or treadmill test signal the need for more invasive procedures.

Electrocardiogram

The electrocardiogram (known popularly as the ECG or EKG) is a graphic representation of the electrical currents that run through the heart as it pumps. The ECG can be taken while you are resting or exercising (usually on a treadmill), and the only discomfort you might experience is several small electrodes attached to your skin.

Normal ECG readings in women during exercise are likely to mean that no heart disease is present; and—compared with men—abnormal readings are much more likely to be false positives; that is, not truly a sign of heart disease. One study found false positives in only 8 percent of the men tested and a whopping 67 percent of women undergoing the same test. In other words, even if stress testing is positive, there's still an excellent chance that your heart is healthy. Some doctors skip the stress test altogether, especially in a patient with clear physical symptoms (such as repeated incidents of angina), and move directly to more specific testing.

Radionuclide Studies

These studies follow radioactive substances that have been injected into the bloodstream. One common example, exercise thallium scintigraphy, uses computer imaging to track an injection of radioactive thallium through the bloodstream and assess bloodflow to the heart during exercise. This test also turns up many false positives in women because breast tissue can create a shadow that looks like a blockage. Another form of radionuclide testing is used for women who are unable to exercise strenuously enough for exercise testing. The drugs used in these tests, dipyridamole (Persantine IV) or adenosine (Adenocard), mimic the effects of exercising.

Echocardiogram

Echocardiography is a diagnostic method that measures ultrasound waves. The waves are transmitted into the body, and the echoes that come back from the heart's surface are transformed into a video picture showing the size, shape, and movement of the heart. Like radionuclide studies, echocardiography can be combined with exercise or drug­induced stress to study the heart and blood flow under stress conditions. Dobutamine (Dobutrex) can be administered during echocardiography to simulate the effects of exercise on the heart. Doctors frequently use echocardiography to confirm a suspicion of mitral valve prolapse and other valvular disorders.

Angiogram

Angiography is a way of seeing the interior of the heart and blood vessels. In a procedure more invasive than electro­ or echocardiography, a catheter (a long, flexible tube) is inserted into a large blood vessel, usually the femoral artery in the upper thigh, and threaded up to the heart in a procedure called cardiac catheterization. Contrasting die is injected through the catheter, allowing x­rays of the heart and blood vessels that can show the degree of blockage.

The angiogram is probably the most definitive tool for diagnosing heart disease, but because it carries a small risk of injury or death, it is not routinely prescribed. One of the controversies about women's health care focuses on the angiogram, which is ordered much less frequently for women than for men. One study found that 10 times as many men as women (40 percent, compared to 4 percent) were referred for an angiogram after a positive ECG stress test. This is partly because of the known high number of false positives in women's stress ECGs, but it may also reflect a pervasive pattern of less aggressive treatment of heart disease in women. Many physicians treating women with heart disease believe that this pattern is changing as the medical profession and women themselves become more aware of the true risk of serious heart disease.

Treatment Options Today

Return to top

As with most other diseases, there is a broad range of treatments available for heart disease, proceeding from the minimum—lifestyle and behavior changes—to the maximum—heart transplant. Lifestyle changes to treat heart disease parallel those to prevent it. A primary difference is that if you already have heart disease, you should consult closely with your doctor as you consider which changes will be most appropriate.

There are, of course, many intermediate steps between simple lifestyle changes and heart transplant. These include a variety of drug therapies; angioplasty, in which arteries are widened with the insertion of a balloon; and several different surgical procedures including valve replacement and bypass operations.

Heart disease is really a variety of diseases that strike different parts of the circulatory system and act in different ways. They are progressive, interrelated conditions, and treatment of one problem early in the continuum—for example, coronary artery disease—can prevent more serious consequences such as heart attack.

Obviously, there is no single treatment. And there are no definitive solutions to the problem of determining which therapies—most of which have been tested primarily on men—will work best for women. But understanding the available options is an important first step in deciding, with your doctor, which treatment is best for you.

Drugs

Drugs have been used to treat heart disease for centuries. There's a wide variety; and they work in a variety of ways. Little is known about whether heart medications affect women differently than men. But so far, indications are that the drug's effects are similar, regardless of gender, although the most effective dosage levels may vary.

Digitalis. Two hundred years ago a British physician discovered that digitalis, an extract from the foxglove plant commonly grown in English gardens, strengthens the contraction of the heart muscle. This drug is still used to treat congestive heart failure, and is also useful in correcting irregular heartbeats.

Nitroglycerin. Nearly a century later, a Scottish medical student theorized that amyl nitrite, known to relax the capillaries, could relieve the pain of angina by increasing blood flow to the heart. A form of that drug, nitroglycerin, is still widely used for this purpose.

Beta blockers, often used to treat high blood pressure, are among the most valuable drugs used to treat the heart. They act to block the activity of the beta-adrenergic system, a highly integrated nerve and hormonal system that affects the heart's rhythm and strength of contractions, among other things. Propranolol (Inderal), the first and most widely used of the beta blockers, has been found effective for treating angina, high blood pressure, and migraine headaches. This, and related drugs, are also effective in preventing second heart attacks.

PUTTING THE PRESSURE ON PLAQUE

For many people with clogged coronary arteries, angioplasty now provides a less traumatic alternative to traditional bypass surgery. During this newer procedure, a balloon-tipped catheter is threaded up through the circulatory system until it reaches the diseased artery, then inflated to squeeze back the encroaching plaque. Often the balloon is surrounded by a collapsible mesh tube called a stent. When the expanded stent has been lodged firmly against the plaque, the balloon is deflated and withdrawn.

Calcium channel blockers were first approved to treat irregular heartbeat, but were found to have other uses. The flow of calcium across cell membranes in the heart muscle plays a large role in determining how hard the heart contracts: decreasing the flow of calcium across membranes can improve heart function. These drugs—the most widely used is verapamil (Isoptin, Calan)—also relieve the pain of angina by relaxing the coronary arteries and helping the heart beat more easily. Calcium supplementation (either dietary or through pills) is not thought to effect the action of calcium channel blockers.

Thrombolytics, known as clot-busters, are among the wonder drugs of modern heart medications. Drugs such as Tissue-Plasminogen Activator or t­PA (Activase) and streptokinase (Streptase) dissolve blood clots when injected into the bloodstream. If administered shortly after a heart attack, they can clear the obstruction before heart tissue is deprived of oxygen and dies. Speed is critical for the effectiveness of these drugs. New federal guidelines recommend that most heart attack patients be given a thrombolytic within 30 minutes of arrival at the emergency room.

Some of the limited existing data about women and thrombolytics indicate that women are not as likely as men to get these drugs in the emergency room, and when they do, the drugs do not work as effectively. No one doubts, however, that these are important drugs to use in treating both women and men.

Angioplasty

This procedure involves attaching a tiny balloon to the tip of a catheter, threading it up through an artery until it reaches a developing blockage, then inflating the balloon to push the blockage aside and enlarge the artery opening, or lumen. The technical name for this procedure is percutaneous transluminal coronary angioplasty or PTCA. It has a high success rate, although blockage returns in many patients in about 3 months. A refinement of angioplasty is a procedure using a collapsible stent, a stainless steel tube that is inserted and opened by inflating the balloon, then left in place as a more permanent vessel opener when the balloon is removed. Valvuloplasty, a procedure similar to angioplasty, uses the balloon to open an obstructed portion of a heart valve.

Women undergoing angioplasty have lower success rates and higher complication rates than men. This may be because women are usually sicker and older when the procedure is performed, and because the generally smaller surface area of the interior of their blood vessels makes the treatment more delicate. Technological advances in designing equipment specific to the needs of women may help to eliminate these disparities.

Surgery

Women are referred for heart surgery less frequently than men and they have poorer outcomes, including a higher incidence of death. Still, surgery can be very effective, although even when successful, it is seldom the final “cure,” and many heart patients continue to require some kind of daily medication thereafter.

Coronary artery bypass graft (CABG), known popularly as simply bypass surgery, is the most common form of heart surgery. In bypass surgery, a clogged portion of a coronary artery is replaced with a short piece of a blood vessel that has been removed from another part of the patient's body.

Women are probably referred less than men because their outcomes are not as good. This could be a blessing: Many think that CABG is prescribed for men more often than it should be. Women are sicker and older when they are referred for bypass surgery, which may help explain the poorer outcomes. Once a woman leaves the hospital following this surgery, however, her long term survival rate is equal to a man's.

Valve replacement surgery is used when medications are not effective in correcting the problems of damaged or congenitally malformed heart valves. The natural valve is replaced with an artificial one made of light metal or plastic, or with a specially prepared valve taken from an animal, most often a pig. Little is known about the different outcomes in men and women who receive these replacements.

Electrical Devices. Some people have an irregular heartbeat that cannot be corrected with medications. If the heartbeat is too slow, a surgically implanted pacemaker can be an effective device to increase the heartbeat, and many people live for years with one of these devices in place. Often medications are still required after insertion of a pacemaker. Another device, the implantable cardioverter­defibrillator, automatically detects the rapid or uncontrolled beats of ventricular tachycardia or fibrillation when they occur and within seconds generates an electrical shock to correct the problem.

HOW BYPASS SURGERY GETS ITS NAME

When a blockage occurs in one or more of the coronary arteries supplying the heart muscle with blood, the most effective solution is often to establish a new route around the barrier—to literally bypass the site of the problem. To do this, surgeons generally snip out a small portion of the saphenous vein in the leg and graft it to the diseased coronary artery on either side of the blockage. Short of an open heart procedure or a transplant, this operation is about as major as surgery gets.

A heart transplant is the most dramatic of all treatments. The procedure is used most frequently in patients with severe cardiomyopathy (heart muscle disease). Heart transplants are very rare, since they depend on the advanced technological resources of a sophisticated medical center and the availability of a compatible donor heart. However, with advances in anti-rejection drugs, the operation is recognized as an option that can prolong life by years in appropriately selected patients. Because it is still so rare, little data is available about the differences between men and women who have received heart transplants

Cardiopulmonary Resuscitation

CPR is an emergency intervention for someone suffering cardiac arrest. Designed to keep oxygenated blood flowing to the heart and brain until the heartbeat resumes or life support is started, it is a combination of chest compression and mouth-to-mouth breathing. Only people properly trained in CPR should attempt to administer it.

Other Dangers

Return to top

As is the case with many illnesses, heart disease in women can be complicated by other factors. The two most important are diabetes and pregnancy.

Diabetes

Diabetes most commonly occurs after the age of 45. Depending on severity, it is treated with oral medications that lower blood sugar levels or with regular injections of insulin. More women than men have diabetes, but this may simply be because there are more women than men in the older age groups.

Ischemic heart disease is the most common cause of death in diabetics, even though diabetes itself is listed as one of the top-ten causes of death in this country. At any given age, a woman with diabetes has more than twice the risk of having a heart attack than a woman without diabetes. The increased risk of heart disease in diabetics is also greater in women than in men. Diabetics are also more likely to be overweight, have high cholesterol, and suffer from hypertension, all of which are also risk factors for heart disease.

Pregnancy

Because coronary artery disease usually strikes later in life, it is rarely a complication during pregnancy. However, a number of heart problems, such as congenital defects and valvular disease, do occur in women of childbearing age. Most of these diseases can be well-managed in pregnancy and present little danger to mother or baby. There is even a report of a woman who had a baby four years after having had a heart transplant.

Some symptoms of pregnancy are very similar to symptoms of heart disease; for example, fatigue, shortness of breath, swelling in the arms and legs, and sometimes palpitations. If you are pregnant, and concerned about such symptoms, discuss them with your doctor; usually there is little cause for alarm. Similarly, heart murmurs are commonly heard during pregnancy, but usually just indicate increased blood flow across the aortic and pulmonary valves, rather than a valve abnormality. Your blood pressure should be monitored regularly during pregnancy, because it often rises.

Most diagnostic techniques for heart disease can be used during pregnancy, but those requiring radioactive substances should normally be avoided because of possible harm to the developing baby. (Radioactive substances are sometimes used during pregnancy when the need for diagnosis in the mother outweighs the risk to the baby.) Echocardiography is not harmful to the child, and is used for diagnosis in a pregnant heart patient whenever needed.

More Women's Health...