Heart Attack: Key Q&A

What is a heart attack?

A heart attack is an event that results in permanent damage or death to part of the heart muscle. It is also known as a myocardial infarction. A heart attack may be the result of a number of chronic heart conditions. However, the trigger for a heart attack is often a blood clot that has blocked the flow of blood through a coronary artery. In most cases, the blood clot is linked to atherosclerosis. Atherosclerosis is a condition that occurs when plaque builds up in the arteries, making them stiff and narrow.

Do men and women experience heart attacks in the same way?

Not necessarily. The heart attack symptoms that women get are often different from those of men. Like men, they may experience shortness of breath, weakness, unusual fatigue and cold sweats. But unlike men, they may not experience chest pain. They may instead feel pain similar to severe heartburn high in the abdomen or pain in the breast, back, neck or jaw. They may also experience dizziness. Women have also reported symptoms of unusual fatigue, sleep disturbances, shortness of breath, indigestion and anxiety in the weeks leading up to their heart attack.

Do genetics play a role in heart attacks?

Yes. People whose parents have had a heart attack before age 60 have a higher risk for developing coronary artery disease at a young age. One study looked at people, with an average age of 19, whose parents had early heart attacks. These subjects had thicker artery walls and worse artery function than is normal for their age. Researchers suggest that a genetic cause may be responsible and stress the need for healthy lifestyle changes among people in this situation.

Research has also shown that people with one particular estrogen gene variant are three times more likely to have a heart attack than those without the variant. Both men and women have the gene, but only a small number have the variant that increases heart attack risk.

Finally, researchers have identified a gene mutation that causes heart attacks. While the mutation was discovered in only one family, and is unlikely to be found in others, the finding provides new insight into the genetic component of heart disease.

Does race play a role in heart attacks?

Yes. African-Americans have greater rates of heart disease and heart attack than do white Americans. The reasons for this are currently being explored in the Jackson Heart Study, which was launched in 2000. Sponsored by the National Institutes of Health, it is modeled after the famed Framingham Heart Study. More than 6,000 black American men and women ages 35 to 84, in Jackson, Mississippi, are being studied. A combination of physical examinations and questionnaires are being used to establish risk factors for cardiovascular disease in black Americans.

Is menstruation a factor in heart attacks?

Possibly. Recent studies have explored whether a woman's menstrual cycle plays a role in heart attack risk. One found a higher risk of heart attack at the onset of the menstrual cycle, when estrogen and progesterone levels are at their lowest. Researchers are unsure of the reason but stress that the increase in risk is very low.

Another study focused on a possible association between irregular periods and heart disease. Spanning 14 years, it followed 82,000 female nurses aged 20 to 35. Compared to those having regular menstrual cycles, the nurses with irregular periods had a higher incidence of heart problems. Researchers conducting the study did not feel that irregular periods by themselves caused heart disease. Rather, they may reflect some other underlying condition that can increase risk for heart disease.

Is there a difference in outcome between totally blocked and partially blocked arteries?

Yes. A totally blocked artery is generally considered less of a threat in terms of a future heart attack than a partially or almost totally blocked artery. This is because there is no potential for further damage with the totally blocked vessel. The areas of the heart formerly supplied by that vessel are permanently scarred or "dead," with no need for an oxygen-rich blood supply. Surgical bypass of a totally blocked artery that supplies a "dead" area of the heart may serve little or no purpose. Instead, the goal of the physician and the patient is to prevent further damage in those areas in which good or partial function still exists.

Of course, it's best not to have any damage or blockage at all. That is why it's important to follow steps to prevent a heart attack or seek immediate emergency care if you are experiencing a heart attack.