Peripheral Artery Disease is caused by a thickening of the inside walls of the arteries of your legs. This thickening, called atherosclerosis, narrows the space through which blood can flow, decreasing the supply of oxygen and nutrients to the legs and feet. It can affect both legs, but most often symptoms begin in one leg.

Atherosclerosis usually occurs when a person has high levels of cholesterol, a fat-like substance, in the blood. Cholesterol and fat, circulating in the blood, build up on the walls of the arteries. When the level of cholesterol in the blood is high, there is a greater chance that it will be deposited onto the artery walls. Plaque formations can grow large enough to significantly reduce the blood's flow through an artery. When a plaque formation becomes brittle, it may rupture, triggering a blood clot to form. A clot may either further narrow the artery, or completely block it. When that blockage occurs in a coronary artery, it can cause a heart attack. When it occurs in a carotid artery, it can cause a stroke. If the blockage remains in the peripheral arteries, it can cause pain, changes in skin color, sores or ulcers and difficulty walking. Total loss of circulation to the legs and feet can cause gangrene and loss of a limb.

Some patients with PAD experience cramping in the arms or legs while moving the extremity. This cramping is called claudication. Claudication comes from the Latin word claudicare meaning to limp. The discomfort usually occurs in large muscles in one or both legs during physical activity, such as walking. Not every person with PAD experiences leg pain. Some people may feel a tightness, heaviness, cramping, or weakness of the leg.

When people experience claudication, the discomfort tends to occur consistently, typically each time a person walks a certain distance, and fades within a few minutes after a person stops to rest. Walking up stairs or uphill may bring on the discomfort more rapidly. As leg artery disease progresses, leg pain may occur at shorter walking distances. Unfortunately, it is estimated that 50 percent of patients with PAD do not have the classic symptoms of claudication.

Other patients may have non-healing ulcers or gangrene. There are also some less-common symptoms that signal PAD. It is important to visit your physician early for proper diagnosis. The most common symptom is cramping, pain or tiredness in the leg or hip muscles while walking or climbing stairs. Typically, this pain goes away with rest and returns when you walk again.

PAD is usually diagnosed by using physical exam, ultrasound or CT scans. All are simple non-invasive procedures which are performed with minimal discomfort.

Treatment

Treatment for PAD focuses on reduction of symptoms and prevention of further progression of the disease. In most cases, lifestyle changes, exercise and claudication medications are enough to slow the progression or even reverse the symptoms of PAD.

Quitting smoking: Smoking has adverse effects on the blood vessels. Among other things, it accelerates the progression of atherosclerosis and diminishes the blood's capacity to carry oxygen to body tissues.

Exercising: Eating right and exercising regularly: Some people who eat foods lower in fat, cholesterol, and calories, and who perform aerobic exercise for 20 to 30 minutes every other day can reduce their blood cholesterol levels by up to 15 percent, which also helps prevent the progression of atherosclerosis.

Medication: Medication is also used to treat early cases of PAD. Medications used for treating atherosclerotic disease in the legs include:

• Antihypertensives, which help control blood pressure;               
• Cholesterol-lowering drugs, such as statins; and               
• Antiplatelet drugs, which block platelets, or cells that make blood clot more easily. Antiplatelet medications minimize the chance that clots will block arteries narrowed by atherosclerotic plaques. Antiplatelets are used to reduce the risk of heart attacks, strokes, or death from circulatory causes and include aspirin and other, stronger medications such as clopidogrel.

Although these drugs do not treat leg artery disease or its symptoms specifically, they can help prevent atherosclerosis from worsening in the leg arteries and in the coronary and carotid arteries as well. Medications that treat diabetes may also help control leg artery disease in cases where diabetes is a contributing cause of PAD.

Endovascular Treatments:

Angioplasty and Stenting: Minimally invasive procedures such as angioplasty and stenting may be recommended for advanced cases of peripheral artery disease. During angioplasty, a physician makes a small incision into the skin above an artery in the arm or groin in order to access the artery. The physician then threads a balloon-tipped catheter from the incision site through the arterial system to the leg artery that is blocked or narrowed. Once the balloon is positioned under the plaque, the physician inflates it to break up and compress the plaque and widen the blood vessel, improving blood flow through the artery. In some cases, the physician may then insert a stent, a small metal-mesh tube, to prop open the artery following angioplasty.

When angioplasty is successful, it has excellent results. Approximately 60 to 70 percent of patients who have an angioplasty have patent vessels, or vessels that remain open to provide adequate blood flow to the legs, 2 years after the procedure. The initial failure rate for angioplasty in patients with leg artery disease is only about 10 percent. Failure may occur if the catheter is unable to move through the blockage or a weakened artery collapses after angioplasty and is impossible to keep open. 

Other techniques, including cryoplasty (a technique to freeze the plaque to prevent renarrowing) and atherectomy (a method of removing the plaque through a catheter) are also being used in treating leg arteries. Newer stent designs have demonstrated early improvements in keeping leg arteries open.

For more advanced forms of leg artery disease, procedures that are more invasive than angioplasty, usually a surgical bypass graft or endarterectomy, may be needed.