Peripheral Arterial Disease

Peripheral Arterial Disease (Lower Extremity Arterial Occlusive Disease)

Atherosclerosis, or hardening of the arteries is caused by the accumulation of a fatty substance called plaque on the inside of the walls of arteries, is a condition that affects up to 35% of Americans. Atherosclerosis can cause narrowing of any of the arteries throughout the body. This narrowing or occlusion is called stenosis, and can occur in the arteries in the (the legs), or more infrequently in the arms. When it occurs in the legs and feet, it causes a disease known as lower extremity arterial occlusive disease.

Narrowing of the arteries in the lower extremities of the body decreases the blood supply to the muscles and tissues in the surrounding area (poor circulation). Lower extremity arterial occlusive disease is often present in conjunction with other conditions, such as carotid artery disease and heart disease. Risk factors for lower extremity arterial occlusive disease include family history of atherosclerosis, high blood pressure, diabetes, high cholesterol, and advanced age, as well as factors such as a sedentary lifestyle and smoking. Smoking is the number one risk factor for cardiovascular diseases.

How is Peripheral Arterial Disease Diagnosed?

The symptoms of lower extremity arterial occlusive disease include:

  • Pain in the calves or thighs while walking (claudication)
  • Pain in the feet at rest
  • Coolness of legs and feet
  • Poor healing of wounds in the extremity
  • Ulcers of the feet and legs
  • Black discoloration of the toes or skin (gangrene)

Claudication is the most common symptom of lower extremity arterial occlusive disease. Some people may also experience numbness, weakness, or cold in the feet or legs. As the disease progresses, pain may also be felt at rest in the toes. The skin around the occluded artery may become discolored, and ulcers may develop, which can turn gangrenous if untreated. The development of ulcers indicates that the blood supply to the muscles and tissues in that area has been cut off.

In order to determine the severity of the condition, the doctor will conduct a blood pressure test comparing the blood pressure measurement in the ankle to that in arm. The result of this test, called the ankle brachial index (ABI) will evaluate the extent to which the blood supply is limited in the leg.

Imaging tests may also be necessary to determine the location and the extent of the arterial narrowing (stenosis) in the legs. These tests may include angiography or Magnetic Resonance Imaging (MRI).

How is Lower Extremity Arterial Occlusive Disease Treated?

If symptoms are mild to moderate, the disease can be well managed by lifestyle changes such as a smoking cessation, regular exercise, and management of related conditions such as diabetes, high blood pressure, and cholesterol levels. Exercise can help tremendously in relieving symptoms. Blood-thinning drugs or other kinds of medication may also be prescribed.

In some cases, a procedure may be required to relieve the narrowing in the artery and restore blood flow to the leg. Arterial stenosis may be treated using minimally invasive procedures such as angioplasty and stenting to improve blood supply to the extremity.

However, if the disease is very advanced, or if it occurs in an artery that is difficult to reach with a catheter, arterial bypass surgery may necessary in order to restore blood flow.

Angioplasty and Stenting for Arterial Occlusive Disease

Because they are such simple procedures, angioplasty and stenting are often used in cases where patients would be poor candidates for open surgery. However, they are also being used more and more in all kinds of patients, as they are less invasive and have a quicker recovery time compared to open surgery. The techniques work best when the diseased portion of the artery is relatively small, and when the diseased artery is easily accessible with a catheter.

Angioplasty and stenting for occlusive (blocked) arteries are minimally invasive procedures that can be performed on blockages (occlusions) in the arteries of the kidneys (renal arteries), intestines (mesenteric arteries) and lower extremities (femoral, tibial arteries). Carotid angioplasty and stenting can also be performed. Angioplasty and stenting require only local anaesthesia and intravenous sedation (relaxing medications). During angioplasty, a balloon tipped catheter is inserted through an artery in the groin via a needle puncture. The catheter is pushed through the artery to the point of occlusion and the balloon is then inflated, to expand the opening in the artery. This procedure often improves the blood-flow through the artery.

Sometimes, however, angioplasty does not sufficiently open the artery and the use of a stent is also required. A stent is a synthetic support structure similar to a spring. It is similarly inserted to the point of occlusion in the artery loaded on the balloon tipped catheter. Once in place, it is expanded by inflating the balloon, and left permanently in the artery to provide a reinforced channel through which blood can flow.

Patients generally go home the day after the procedure.

Open Surgery

Arterial Bypass Surgery

Bypass surgery for arterial occlusive disease requires general anesthesia. Surgically correcting the decreased blood flow through the renal or mesenteric artery requires the placement of a bypass graft on the artery. The graft is either made of synthetic material, or it may be a natural vein taken from another part of the body. During the procedure, the surgeon will make an incision to expose the diseased (blocked) artery, and then attach one end of a bypass graft to a point above the blockage in the artery and the other end to a point below the blockage. The blood supply will then be diverted through the graft, around the blockage, bypassing the diseased section of the artery. None of the diseased artery is removed. In-hospital recovery from the surgery will take 3-5 days.

In some cases, angioplasty and stenting, which are minimally invasive procedures, may be utilized instead of open surgery to treat arterial occlusive disease.