Features January 2011 Issue

Know How to Respond If You Have PAD and Experience A “Leg Attack”

Understand the symptoms that require immediate medical attention if you have peripheral arterial disease. Critical limb ischemia could lead to amputation.

Peripheral arterial disease (PAD) affects about nine million Americans, according to the American Heart Association. In PAD a buildup of plaque in the legs, often occurring in the femoral arteries, can reduce blood flow from the heart to the lower limbs. For most people with PAD, this results in cramping pain in the calf muscles when walking, or in other types of leg pain and decreased function. "However in severe PAD cases, a condition called critical limb ischemia (CLI) can develop," says Heather Gornik, MD, a cardiologist at Cleveland Clinic’s Robert and Suzanne Tomsich Department of Cardiovascular Medicine. "Sometimes referred to as a ‘leg attack,’ CLI can be more deleterious to your health than heart attack or stroke."

Severe blockages

In CLI, severe blockages in the arteries in the lower legs reduce blood flow to the extent it causes "ischemic rest pain": severe pain in the feet or toes. "The pain typically occurs at night, when you’re lying down, and can continue for hours at a time," says Dr. Gornik.

Alan Hirsch, MD, adjunct professor in the Division of Epidemiology at the University of Minnesota School of Public Health, notes that the poor circulation that occurs with PAD also can result in ulcers and wounds that won’t heal. "These often are the earliest sign that PAD might result in gangrene and/or limb loss," he says. Amputation occurs in about 25 percent of all CLI patients, according to the Vascular Disease Foundation.

In some cases, PAD and CLI can be diagnosed with a physical examination. "Your doctor will feel the pulses in your legs and note that they are diminished or absent," says Dr. Gornik. "Alternately, he or she may use a stethoscope to listen for a ‘bruit’—a term used to describe the sound blood makes as it flows past an obstruction—in the arteries of the legs."

However, in most cases, another test will be needed to confirm the diagnosis of PAD. "The ankle-brachial index test (ABI) is the most common test used," Dr. Gornik confirms. "It involves measuring blood pressures at the arms and the ankles, and dividing the systolic (upper number) blood pressure in the arm by the systolic blood pressure at the ankle." A result of 0.7 to 0.9 is classified as mild ischemia, with 0.4 to 0.69 considered moderate ischemia, and 0.39 or less, severe ischemia with a danger of limb loss. Imaging tests such as ultrasound, CT scan, MRI and angiography, also may be used to detect the severity and location of blockages in the legs.

Treating CLI

"If a patient with PAD has signs of CLI, immediate treatment is essential to re-establish blood flow to the affected area," Dr. Gornik explains. "The number one priority is to preserve the limb," Dr. Hirsch confirms.

Medications may be prescribed to reduce the effect of the underlying PAD, with contributing factors such as high blood pressure, high cholesterol and diabetes the main targets for drug treatment. You’ll be given painkillers, and anti-platelet medications or anticoagulants, such as aspirin, clopidogrel (Plavix), or warfarin (Coumadin), to help prevent blood clots. "These medications are critical so that heart attack and stroke, both major associated PAD and CLI risks, don’t occur," Dr. Hirsch adds.

Surgical treatments can be very successful. Angioplasty is one option: It involves having a small balloon catheter inserted into the femoral artery through a puncture in the groin. It is fed through the artery to the site of the blockage, under X-ray guidance, and the balloon is inflated to open the artery. "A wire mesh tube called a stent is often placed at the area of the blockage, as this can help to keep the artery open," says Dr. Hirsch.

Another option for more serious cases is surgical bypass utilizing one of your own veins or a synthetic tube that is attached to the artery above and below the area of blockage to re-route blood. "This typically has a good success rate," Dr. Gornik notes, "but you’ll need to be admitted to the hospital for several days, and the recovery time is longer than it is with angioplasty and stenting."

In the most severe cases of CLI, where there is gangrene, severe non-healing wounds, or few options for improving blood flow to the leg, amputation of the foot or leg may be required. "The goal of CLI treatment is to avoid amputation and protect the limb, so early recognition of this limb-threatening condition is very important, says Dr. Gornik. "If you have PAD and have any of the signs of CLI, such as worsening leg pain with walking, pain in your foot or leg at rest, a non healing sore, or severe color changes of the foot, let your doctor know about this straightaway."

Patients (and their families) with PAD deserve, as for any chronic illness, access to accurate health information, Dr, Hirsch adds.

This can be obtained via the Vascular Disease Foundation
(www.vdf.org) and its PAD Coalition (www.padcoalition.org), or via its PAD book for the public, 100 Questions and Answers about Peripheral Artery Disease.