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 heart disease. Coronary heart disease (CHD) is the leading cause of heart attacks. CHD is a condition in which the coronary arteries (the major blood vessels that supply the heart with blood) get clogged up with deposits of cholesterol. These deposits are called plaques.
The most common form of heart disease is coronary artery disease, which can lead to heart attack, according to the CDC. Heart attack occurs when the heart muscleâs blood supply is cut off by a blood clot in one or more pulmonary veins or arteries.