Pre-Algebra on Khan Academy: No way, this isn't your run of the mill arithmetic. This is Pre-algebra. You're about to play with the professionals. Think of pre-algebra as a runway.
Heart attack - Causes. Heart attacks are caused by the blood supply to the heart being suddenly interrupted. Without this supply, heart muscles may be damaged and begin to die. Without treatment, the heart muscles will experience irreversible damage.
Understand Heart Attack Heart attacks are caused by heart disease, which is the number one cause of death among both men and women in the United States. According to the American Heart Association, every year in the United States roughly 785,000 people will have their first heart attack.