Evaluation of Peripheral Arterial Disease

The pathogenesis of arterial stenosis or occlusion may be secondary to a wide spectrum of etiologic factors including atherosclerosis, thrombosis, embolic events of various etiology, fibromuscular dysplasia, vasculitidies, dissection, trauma, external compression, and vasospastic syndromes. Atherosclerosis is by far the most common cause of arterial stenosis. Atheromatic plaques have been identified as early as the first two decades of life, but usually become hemodynamically significant after the age of 50. They can develop in most of the arteries in the body, and are most commonly located in the area of arterial bifurcations. A hemodynamically significant arterial stenosis reduces blood flow in the capillary bed distal to it. The extent of this interference is related to the severity of the stenosis and is determined by strict hemodynamic principles. Tissue perfusion distal to an arterial stenosis can be maintained by development of a network of collateral vessels around the stenosis,