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.
slide 5 of 6. Heart Attack A heart attack may cause a low pulse and high blood pressure. A heart attack is characterized by insufficient oxygen getting to the heart due to blocked blood vessels. Also known as a myocardial infarction, the heart muscle can either become damaged as a result or the heart muscle can die.