In our days CHD is the leading cause of death in the western countries. Atherosclerosis (thickened artery walls) or the narrowing of the coronary arteries, caused by an inflammation or a spasm of an artery, may impair or even fully block the blood flow, leading to angina pectoris, heart attack, or sudden death. Most heart attacks may occur with less than 50 % blockage of an artery.
The progression of atherosclerosis underlies for many years before CHD symptoms arise. The symptoms are usually, discomfort in chest region, pain may radiate to the left arm, shoulders, back, throat, even teeth. In angina pectoris the symptoms arise by exertion, and subside with rest. In heart attack, the pain may be severe, last longer, and occurs without exertion.