What is a heart attack?
Approximately 1.1 million Americans--both men and women--die each year from heart attacks, which are the leading cause of death for Americans.  But what exactly happens during a heart attack?  And how can we describe the process?

Myocardial infarction, or a heart attack, occurs when the heart muscle tissue is deprived of its normal blood flow.  This partial or complete reduction of healthy blood flow to the heart can kill or seriously injure healthy heart muscle tissue, thus killing or seriously injuring a person.  While a heart attack may occur suddenly, this process of blood deprivation to the heart usually occurs for several hours.  If a healthy, normal flow of blood is provided to the heart in sufficient time, then damage to the heart muscle tissue may be reduced, allowing the heart, and therefore the person to live.

Do doctors know what causes heart attack?  And what can put you at risk of having a heart attack.  Continue reading the next section for more information about causes of heart attack now.