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).
Common causes of heart failure include the following: 1  Damage from a prior heart attack â Also called a myocardial infarction, a heart attack occurs when an artery that supplies blood to the heart is blocked so that no oxygen reaches the heart muscle. When this happens, part of the heart dies.. The medical term for the area of dead muscle is called the infarct.. The remaining, healthy tissue must take over the job of pumping blood, an extra burden that may weaken the heart's pumping ability.