Similar to pathology in the coronary arteries, the pathologic hallmark of the lesions involves plaques of atherosclerosis with calcium deposition, thinning of the media, patchy destruction of muscle and elastic fibers, fragmentation of the internal elastic lamina, and thrombi composed of platelets and fibrin (Duerschmied et al., 2006, 310-315). According to statistics delineated in different articles, the primary sites of involvement are the abdominal aorta and iliac arteries comprising 30% of symptomatic patients; the femoral and popliteal arteries consisting of 80 to 90% of patients, and the more distal vessels, including the tibial and peroneal arteries making 40 to 50% of patients (McDermott, 2006, S2). Mechanically and topographically, atherosclerotic lesions occur preferentially at arterial branch points, which are sites of increased turbulence leading to altered shear stress, and hence injury to the tunica intima. Epidemiologic and demographic data suggest that the distal vasculature is most commonly involved in elderly individuals, mostly in patients with diabetes mellitus (Marso and Hiatt, 2006, 921-929).
The history and physical examination are usually sufficient to establish the diagnosis of peripheral arterial disease (PAD). An objective assessment of the severity of disease is obtained by noninvasive techniques. These include digital pulse volume recordings; Doppler flow velocity waveform analysis; duplex ultrasonography, which combines B-mode imaging and pulse-wave Doppler examination; segmental pressure measurements; transcutaneous oximetry; stress testing, usually using a treadmill; and tests of reactive hyperemia (Mohler, III, 2003, 2306-2314). In the presence of significant PAD, the volume displacement in the leg is decreased with each pulse, and the Doppler velocity contour becomes progressively flatter. Duplex ultrasonography is often useful in detecting stenotic lesions in native