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.
Coronary artery disease. The most common underlying cause of heart attack is atherosclerosis, a condition in which a fatty substance called plaque builds up on the inside walls of blood vessels. When this occurs in the coronary arteries, it's known as coronary artery disease (CAD).
A heart attack (myocardial infarction) is most often due to a blood clot that blocks blood flow into the heart muscle. Most commonly, this causes a pressure, cramping or squeezing pain in your chest, but the pain can also spread to your neck. heart attack (myocardial infarction) is most often due to a blood clot that blocks blood flow into the heart muscle. Most commonly, this causes a pressure, cramping or squeezing pain in your chest, but the pain can also spread to your neck.