Occlusive atherosclerotic lesions in the extremities, or peripheral artery disease (PAD), is evidence of a systemic atherosclerotic process. The prevalence of PAD is 30% in patients who are 70 years old without other risk factors, or 50 years old with risk factors such as diabetes mellitus or tobacco use. Pathologic changes of atherosclerosis may be diffuse, but flow-limiting stenoses occur segmentally. In the lower extremities, stenoses classically occur in three anatomic segments: the aortoiliac segment (eFigure 12–1), femoral-popliteal segment, and the infrapopliteal or tibial segment of the arterial tree.
Magnetic resonance angiography showing atherosclerotic occlusive disease of the aortoiliac segment. The vessels proximally and distally are relatively unaffected.
Approximately two-thirds of patients with PAD are either asymptomatic or do not have classic symptoms. Intermittent claudication, which is pain with ambulation that occurs from insufficient blood flow relative to demand, is typically described as severe and cramping primarily in the calf muscles.