How does atherosclerosis cause disease?
There are two ways atherosclerosis causes disease; 1) atherosclerosis can limit the ability of the narrowed arteries to increase delivery of blood and oxygen to tissues during periods of increased oxygen demand such as during exertion, or 2) complete obstruction of an artery by a thrombus or embolus (thrombus and embolus are forms of blood clots; see below) resulting in tissue necrosis (death of tissue). Exertional angina and intermittent claudication are two examples of insufficient delivery of blood and oxygen to meet tissue demand; whereas strokes and heart attacks are examples of death of tissue caused by complete artery obstruction by blood clots. There are many similarities between coronary artery diseases (atherosclerosis involving the arteries of the heart) and peripheral artery disease. For example, patients with exertional angina typically have no symptoms at rest. But during exertion the critically narrowed coronary arteries are incapable of increasing blood and oxygen deliv
