A heart attack is the sudden death of part of the heart muscle. Each year about 1 million people have a heart attack and one-third of those attacks are fatal. In developed countries, heart attacks are the single most common cause of death.

Men are more likely to suffer a heart attack than women, and smokers more than nonsmokers. Individuals whose immediate or extended family have had a heart attack are more likely to also have one.

Uncontrollable risk factors include family history, old age, and being male. Controllable factors include smoking, overweight body, diet, and physical inactivity.

Anyone who has suffered a heart attack has an increased risk of suffering another one in the following few years, especially if lifestyle and dietary changes are not made to reverse the factors that caused the first heart attack.

A heart attack requires immediate medical attention. Arrhythmia, an erratic heart rate, is common, and can be fatal if not controlled quickly.

Special hospital coronary care units have trained staff to monitor and treat a recovering heart attack patient. However, some specialists believe these units are actually more stressful and prefer that patients, especially the elderly, be cared for elsewhere in the hospital or at home.