Arteries supply leg muscles with the oxygen and nutrients essential for proper function. Atherosclerosis narrows or blocks the vessels, and the diminished blood supply produces symptoms, the earliest of which is pain or cramping during walking. More advanced disease produces pain at rest, gangrene and the need for amputation. Atherosclerosis is not curable, but some measures can improve blood flow.
Cigarette smoking accelerates atherosclerosis. Compounds in the inhaled smoke act directly on the vessel walls to narrow them and decrease blood flow. Secondhand smoke inhalation has the same damaging effects. Avoiding tobacco smoke will eliminate its contribution to atherosclerosis and relax the artery walls.
The larger arteries are the ones primarily affected by atherosclerosis.
Smaller, secondary vessels are capable of growing in size and increasing the blood that flows through them. They are known as collateral vessels, and they work according to the principles of supply and demand: They respond to exercise with increased flow. Regular sessions of walking several steps beyond the onset of pain will stimulate that growth and develop detours around the diseased artery.
For patients in whom smoking cessation and exercise are not sufficient, doctors may prescribe medications. Cilestazol (Pletal) inhibits an enzyme in the vessel wall and causes dilation. The widening of the artery decreases resistance to blood flow. Cilestazol cannot be used in patients with heart failure, however, due to serious side effects. Pentoxifylline (Trental) makes blood cells more flexible and more easily pushed through narrowed vessels by the pumping action of the heart. Although medication is not a substitute for smoking cessation and exercise, it may add to their benefits.
Pain at rest indicates that arterial disease has progressed to the point that tissue loss and amputation are imminent. Surgical procedures to open or bypass the vessels are indicated to save the leg. Some vessels can be opened by dilating them with a balloon on a small tube passed through the area of narrowing. A meshed metal tube can be left at the dilated site to keep it open. A vein may also be taken from elsewhere in the leg and connected to the artery at points above and below the blockage. The blood will bypass the diseased segment and nourish the muscles and other tissues beyond it. Artificial blood vessels may be used if a suitable natural vein is not available.