Aortoiliac Occlusive Disease (AIOD)
AlOD occurs commonly in patients with peripheral arterial disease (PAD). Obstructing plaques caused by atherosclerotic occlusive disease commonly occur in the infrarenal aorta and iliac arteries of the pelvis. Atherosclerotic plaques may induce symptoms either by obstructing blood flow or by breaking apart and embolizing atherosclerotic and/or thrombotic debris to more distal blood vessels. This results in what is known "blue toe" or "trash foot" syndrome. If the plaques are large enough to impinge on the arterial lumen, reduction of blood flow to the extremities occurs. The most common symptom of patients with hemodynamically significant AIOD is claudication. Claudication usually occurs first in the calf muscles, although thigh, hip, and buttocks muscles also can be affected when more extensive disease is present. Symptoms of buttock claudication can occur in association with erectile dysfunction in patients with absent femoral (groin) pulses. This constellation of symptoms is termed Leriche syndrome, named for the surgeon who described the condition in 1923. The incidence of PAD is known to increase with advancing age so that by age 70 years, probably 20% of the US population is affected. Atherosclerosis is the most common cause of occlusive plaques in the aorta and iliac arteries. Several risk factors exist for the development of atherosclerotic plaques in the aortoiliac arterial segment. Cigarette smoking and hypercholesterolemia are observed more commonly in patients with AIOD as compared with infrainguinal occlusive disease. In addition, patients with AIOD tend to be younger and less likely to have diabetes.
Treatment: Surgical treatment of AIOD, which usually involves a bypass of the blocked arteries with a synthetic material, is well standardized, and the outcomes are quite good. With the additional techniques of percutaneous transluminal angioplasty (PTA) and stenting, more alternatives are now available for treatment of atherosclerotic occlusive disease in the aortoiliac region.
