Heart Disease

The heart beats about 2.5 billion times over the average lifetime, pushing millions of gallons of blood to every part of the body. This steady flow carries with it oxygen, fuel, hormones, other compounds, and a host of essential cells. It also whisks away the waste products of metabolism. When the heart stops, essential functions fail, some almost instantly.

Given the heart's never-ending workload, it's a wonder it performs so well, for so long, for so many people. But it can also fail, brought down by a poor diet and lack of exercise, smoking, infection, unlucky genes, and more.

A key problem is atherosclerosis. This is the accumulation of pockets of cholesterol-rich gunk inside the arteries. These pockets, called plaque, can limit blood flow through arteries that nourish the heart — the coronary arteries — and other arteries throughout the body. When a plaque breaks apart, it can cause a heart attack or stroke.

Although many people develop some form of cardiovascular disease (a catch-all term for all of the diseases affecting the heart and blood vessels) as they get older, it isn't inevitable. A healthy lifestyle, especially when started at a young age, goes a long way to preventing cardiovascular disease. Lifestyle changes and medications can nip heart-harming trends, like high blood pressure or high cholesterol, in the bud before they cause damage. And a variety of medications, operations, and devices can help support the heart if damage occurs.

Heart diseases include:

  • coronary artery disease: the accumulation of cholesterol-filled plaque in the arteries that nourish heart muscle
  • heart attack (myocardial infarction): the sudden stopping of blood flow to part of the heart muscle
  • heart failure: the inability of the heart to pump as forcefully or efficiently as needed to supply the body with oxygenated blood
  • heart rhythm disorders: heartbeats that are too fast, too slow, or irregular
  • heart valve disorders: problems with the valves that control blood flow from one part of the heart to another part of the heart or to the body.
  • sudden cardiac arrest: the sudden cessation of the heartbeat
  • cardiomyopathy: a disease of the heart muscle that causes the heart to become abnormally enlarged, thickened, and/or stiffened
  • pericarditis: inflammation of the pericardium, a thin sac that surrounds the heart
  • myocarditis: inflammation of the myocardium, the middle layer of the heart wall
  • congenital heart disease: heart diseases or abnormalities in the heart's structure that occur before birth

Heart Disease Articles

Heart attacks in women

Although hard-to-read heart attacks happen to both men and women, they are more common in women. One reason for this is that men's symptoms initially set the standard for recognizing heart trouble. Now a growing body of research shows that women can experience heart attacks differently than men. Understanding sex differences in heart disease is important. Heart disease is the leading cause of death for women. Although it mostly affects older women, it isn't rare in younger women. One in 10 of all women who die from heart disease or a stroke are under age 65, and this age group accounts for one-third of heart- or stroke-related hospitalizations. Even so, younger women and their doctors don't necessarily suspect a heart attack even when all the signs are there. More »

Diabetes Update: 2002

Type 2 diabetes affects approximately 8% of adults in the United States. An additional 10 million Americans are at high risk for the disease. This type of diabetes begins gradually, later in life. Most people with type 2 diabetes produce plenty of insulin, but their tissues resist the action of the hormone, so their blood sugar levels rise; some people develop the disease as their insulin production gradually slows down. Although treatment may prevent some complications of type 2 diabetes, which can include atherosclerosis, vision impairment, and nerve damage, it cannot eliminate the condition altogether. As a result, prevention of type 2 diabetes remains preferable. In a recent study in the New England Journal of Medicine (NEJM), researchers from the Diabetes Prevention Program Research Group sought to determine whether lifestyle intervention or drug treatment could be used to prevent or delay the onset of type 2 diabetes. The researchers gathered 3,234 subjects who they determined to be at high risk for diabetes based on elevated blood sugar levels. They assigned the subjects to one of three interventions: twice-daily treatment with 850 mg of metformin (a drug commonly used to lower blood sugar in people with type 2 diabetes), lifestyle intervention, or placebo. The goal of the lifestyle intervention was to achieve a weight reduction of at least 7% of initial body weight through a low-fat, low-calorie diet, and to complete at least 150 minutes of moderate-intensity physical activity per week. As measured by the researchers, the lifestyle intervention group achieved much greater weight loss and increased their physical activity level more than the metformin or placebo groups. More »

Aspirin and heart disease

The study, published in the May 9, 2002, issue of the New England Journal of Medicine, analyzes the major trials on the subject. Four out of five of the randomized trials show a reduction in cardiovascular events (especially heart attacks) with aspirin use. (In randomized trials, researchers randomly assign patients to one of the treatments being tested.) But the studies' statistics vary wildly. For example, risk reduction ranged from 4%–44%, depending on the study. All but one trial showed that aspirin use increased the risk of bleeding, most commonly in the stomach. Two large observational studies also showed that aspirin use decreased coronary events in both people with and without heart disease. (In observational studies, researchers simply monitor subjects' behaviors and health, they do not test a specific treatment on them.) Subjects' ages had an impact in both studies, with aspirin's benefit on the heart kicking in when subjects hit 50 years old in one, 60 years old in the other. Other trials have found that aspirin has the greatest effect on patients with high risk for heart disease. So what should you do? That depends a lot on your heart disease risk. To calculate your risk go to this downloadable scoring system on the National Institutes of Health Web site. More »