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.
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.