Lower extremity arterial disease is a condition that develops when the arteries in the legs and feet become narrowed, or occluded, by an accumulation of a fatty substance called plaque, which builds up on the inside walls of the arteries. This narrowing is also called stenosis. As the arteries narrow, blood supply to the muscles and tissues in the legs and feet decreases, causing pain, poor healing, and in severe cases tissue death. Lower extremity arterial disease is one manifestation of atherosclerosis, the hardening and narrowing of the arteries due to plaque build-up. Atherosclerosis affects as many as 35 percent of Americans. People with lower extremity arterial disease often have other cardiovascular problems causes by atherosclerosis such as carotid artery disease and heart disease.