Angina pectoris, commonly known as angina, is severe chest pain due to ischemia (a lack of blood, thus a lack of oxygen supply) of the heart muscle, generally due to obstruction or spasm of the coronary arteries (the heart's blood vessels). Coronary artery disease, the main cause of angina, is due to atherosclerosis of the cardiac arteries. The term derives from the Latin angina ("infection of the throat") from the Greek ἀγχόνη ankhonē ("strangling"), and the Latin pectus ("chest"), and can therefore be translated as "a strangling feeling in the chest"...