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.
At the root of the cause for heart attacks is a disease called âarteriosclerosis,â which is the accumulation of âplaqueâ or âcrudâ (cholesterol, fatty deposits, and other substances) on the inner lining of artery walls.This buildup narrows arteries until they become so clogged, blood cannot flow through.t the root of the cause for heart attacks is a disease called âarteriosclerosis,â which is the accumulation of âplaqueâ or âcrudâ (cholesterol, fatty deposits, and other substances) on the inner lining of artery walls. This buildup narrows arteries until they become so clogged, blood cannot flow through.