Peripheral Arterial Disease

Overview

When you were younger, as you began to exercise you would pick up speed and distance and your legs would carry you to your destination, without difficulty or challenge. Your breathing would quicken, your heart rate increase, and the lungs and heart would work together so that increased blood would circulate to the arteries and muscles of your legs. You would walk or run effortlessly.

In some people, however, atherosclerosis, or hardening of the arteries, restricts this blood flow. When your muscles don't get the oxygen and nutrients they need during exercise such as walking, you may experience a cramping discomfort, squeezing or tightness in the calf called claudication, which can be severe enough to make you want to stop exercising. It is sometimes called intermittent claudication because the pain stops with rest, and then you could resume walking. Pain will recur each time you walk a certain distance so you may need to stop several times before you get to where you are going.

This leg muscle fatigue, discomfort or pain is the primary symptom of peripheral arterial disease (PAD). It most commonly affects the blood supply to the legs and results from clogged arteries. People with PAD could have the same disease of the arteries elsewhere in the body, such as the brain, heart or kidneys.

Many people don't experience any leg muscle discomfort or intermittent claudication until the artery is blocked or occluded by 60 percent or more. Thus, during the years or even decades PAD is developing, you may be unaware of what's happening inside the arteries of your body. Even when you start to experience some symptoms, many people just assume these aches and pains in the leg muscles are a natural part of getting old.

However, when arteries are damaged by atherosclerosis in one site (such as the leg arteries), they're likely also damaged in other vital locations (such as the heart or brain). If a blood clot forms in a damaged artery to the heart or brain, it can lead to a heart attack or stroke.

In fact, the risk of dying from a heart attack or stroke is significantly higher in those with PAD compared to those without.

While atherosclerosis is by far the most common cause of PAD, other conditions can cause narrowing such as blood clots, injury to your limbs, inflammation of your arteries (due to other illnesses), or unusual inherited variations of the anatomy of your leg's ligaments or muscles.

According to the Centers for Disease Control and Prevention (CDC), 12 percent to 20 percent of people over 60 have PAD. Many people with PAD have mild or no symptoms, and only about 10 percent of people with PAD have typical intermittent claudication. Nevertheless, PAD is very common and affects about 8 million to 12 million Americans.

Only a small percentage of people with PAD will ever face a risk of amputation. PAD is, however, the leading cause of amputation in people age 50 and over and accounts for an estimated 90 percent of amputations overall.

If you think you might have PAD, talk to your doctor about your symptoms. A number of simple, risk-free and inexpensive tests can help to confirm the diagnosis.

Your risk for PAD increases if you:

• Are over age 50.
• Smoke. Tobacco use is the single greatest cause of PAD. In fact, smokers are diagnosed with PAD as much as 10 years earlier on average than nonsmokers. People with PAD who smoke are also more likely to experience worse symptoms, to require leg bypass surgery and to undergo amputation or die from PAD-related complications.
• Have diabetes. One in three people over 50 with diabetes has PAD, and those with diabetes face an increased risk of amputation due to the development of PAD.
• Have high blood pressure.
• Have high cholesterol levels.
• Have coronary artery disease.
• Have a family history of coronary artery disease or PAD.
• Have high levels of homocysteine, an amino acid, in your blood.
• Are African American

Diagnosis

The first sign of PAD may be symptoms such as intermittent claudication: leg muscle discomfort that gets worse with exercise but improves with rest or warmth.

As PAD becomes more severe, other symptoms in the legs may occur:

• Pain in the foot at rest, or when lying down, that is not caused by arthritis or neuropathy
• Leg sores that don't heal
• Gangrene, or tissue death

If any tissue in the body does not receive the oxygen and nutrients needed via the circulating blood, over time that tissue will die. With very severe PAD, the skin of the feet may break down, forming sores and ulcers and sometimes infection can occur and spread to the bone.

To diagnose PAD, your health care professional should take a thorough medical history and ask about any risk factors such as smoking, diabetes, high blood pressure or high blood cholesterol.

Your doctor will also perform a physical examination feeling the pulse of the arteries in key locations, such as at the groins, at the backs of your knees, the tops of your feet and just behind the bone on the inside of each ankle. Using a blood pressure cuff and a special ultrasound stethoscope called a Doppler, your doctor might also take your blood pressure on each arm and ankle.

Comparing blood pressure readings between the arms and legs determines how well blood is flowing to each limb. This painless procedure is called the ankle-brachial index (or ABI) and helps determine if further testing is needed. The ankle pressure is normally at least 90 percent of the arm pressure, but with moderately severe PAD, the ankle pressure may be less than 50 percent of the arm pressure.

However, this test may not be precise enough in people with diabetes. In those cases, the doctor may take pressure measurements of your toes, or you may be referred to a vascular laboratory for more sophisticated tests described below.

Other possible tests include:

• Duplex ultrasound. This test uses sound waves to determine the site and severity of artery blockages.
• A computed tomographic angiogram (CT). This is a noninvasive test that provides an image of the arteries in the abdomen, pelvis and legs.
• Magnetic resonance angiogram (MRA). This is a noninvasive test that provides information similar to a CT scan but without the use of X-rays. The MRA provides a very detailed picture of the arteries. This test is not accurate or safe in people who have pacemakers or stents.
• Contrast arteriogram. In this test, an X-ray is taken of your arteries after a small tube (catheter) is inserted into an artery and a contrast dye injected. The dye makes areas of atherosclerosis and structural changes more obvious.

Treatment

Treatment goals for peripheral arterial disease (PAD) always include reducing your risk of heart attack and stroke by immediately controlling your risk factors and through the use of medications. Additional goals are to improve your leg symptoms, if these are present, and to reduce the risk of amputation. Once again, it is extremely important that any risk factors be recognized and treated promptly so that your PAD doesn't get worse.

Lifestyle Changes

Lifestyle can profoundly affect your health. If you expose your arteries to damaging factors, you should note that other treatments may not be effective and your health is likely to deteriorate. On the other hand, successful control of your daily habits can usually be enough to slow the progression or even reverse symptoms of PAD. These beneficial lifestyle changes include:

• Stop smoking immediately. This is critical because all tobacco products directly damage the arteries, and nicotine further narrows the blood vessels.
• Exercise. Regular exercise is the most consistently effective treatment for people with PAD. When you walk, your body develops new blood vessels. Walking helps to reduce cholesterol levels, improve weight loss and maintain healthy circulation. Exercise programs are most effective when performed in a supervised setting such as a cardiac rehabilitation program. Simple walking regimens on a treadmill, outdoors or in malls for at least 30 to 60 minutes, five or more times a week, may also help. Your health care professional is likely to ask you to walk each day until leg discomfort develops, then rest, then continue walking until the pain develops again. The goal is to travel longer distances without pain each time you walk.
• Watch your diet. Many people with PAD have high cholesterol and blood pressure levels. A healthful, balanced diet low in saturated fat, salt and cholesterol, and rich in fruits, vegetables, whole grains, beans, fish and low-fat dairy products may help lower cholesterol levels and high blood pressure. However, some people may require medication to reduce cholesterol and/or blood pressure levels and keep them low.
• Maintain good foot hygiene. Check your feet each day for sores, redness or swelling. Wash your feet every day and apply a moisturizing lotion; tuck cotton or lamb's wool between your toes if the skin is starting to crack; and wear cotton socks and comfortable, breathable shoes made of natural materials. Avoid injuring your feet.

Medication

Treatment for PAD always includes the use of medication to reduce the risk of heart attack and stroke and improve symptoms. Medications used include:

• Antiplatelet medications. These drugs, such as aspirin or clopidogrel (Plavix), help reduce your risk of heart attack and stroke. Side effects of aspirin include stomach ulcers and bleeding complications. Side effects of clopidogrel include allergic reaction, bleeding complications, severe headache, confusion or dizziness. Other, less serious, side effects may include upset stomach, diarrhea or constipation, or headache or dizziness. In some people, clopidogrel may not work as it is supposed to. There is a blood test your health care provider can do to check how you respond to this drug. Some drugs used to treat acid reflux interfere with how clopidogrel works so make sure your health care provider knows all of the medications you are taking.
• Cholesterol-lowering drugs such as statins. These drugs not only lower cholesterol but also improve the health of the lining of the arteries (endothelium) and reduce the likelihood that an artery will slowly clog or suddenly be blocked by a blood clot. Most individuals tolerate statins with no difficulty. However, possible side effects include nausea, gas, constipation and muscle pain. Your physician will also monitor your liver function. Any side effects are usually mild and fade as your body adjusts to the drug. If you experience any unusual or persistent muscle soreness or weakness while using these medications, contact your health care professional immediately.
• Cilostazol (Pletal). This drug widens the arteries that supply blood to the legs. It is particularly effective when combined with exercise. Side effects are rare and include headache, mild palpitations, loose stools and nausea. You should not take this medication if you have congestive heart failure.

Nonsurgical Procedures

There are a number of ways health care professionals can open blood vessels at the site of blockages and restore normal blood flow. All of these invasive PAD treatments, whether based on use of a catheter or surgery, are most useful for individuals whose blockages are not widespread or whose blockages are in the arteries closer to the groin.

In these instances, a nonsurgical endovascular procedure can sometimes bring swift relief and may be more cost-effective than surgery. Most endovascular procedures require no more than an overnight hospital stay and little down time afterward.

In these procedures, a tiny tube called a catheter is inserted into an artery to open the blockage. The most common procedures treat the plaque by compressing it and/or displacing it with a metal coil inserted within the artery, called a stent. The two main procedures are:

• Angioplasty. With the help of a catheter and X-ray guidance, a tiny balloon is inserted into the blood vessel through a small opening in the skin and moved through the artery to the site of the blockage, then inflated to open the blood vessel. The balloon is then deflated and removed.
• Stenting. A tiny metal cylinder or "stent" is permanently inserted in the clogged vessel, where it acts like a scaffold to hold it open.

More rarely, physicians may identify a clot that is blocking an artery, stent or bypass graft. If so, thrombolytic therapy may be used:

• Thrombolytic therapy. If you have a clot that's blocking an artery, your doctor may inject a clot-dissolving drug into your artery where the clot is located to break it up. Once the clot dissolves, you will likely need to be on a strong blood thinner like warfarin.

Surgery

• Endarterectomy. This procedure is used when a very short segment of an artery is blocked or severely clogged. The surgeon identifies the location of the blockage, then makes an incision over the area and removes the plaque in the artery's inner lining. This procedure opens the artery, restoring blood flow. It is used most commonly for clogged carotid arteries in the neck and less often for blockages of the leg arteries.
• Bypass. If the blockage is extremely long or has become very hard and calcified with time, surgery may be required to bypass the problem area. A bypass involves using one of the patient's own veins from another part of the body or a synthetic graft to create a detour around the diseased region of the artery.
• Amputation. In rare cases, gangrenous tissue (such as a toe, foot or leg) may have to be removed permanently.

Prevention

There are several things you can do to prevent PAD, including:

• Quit smoking. Smoking damages the inner lining of vessels and makes blood clot more easily.
• Exercise regularly under the supervision of your health care provider to prevent the buildup of cholesterol, help with weight loss and maintain healthy circulation.
• Eat a low-fat, low-salt, balanced diet that includes vegetables, fruits, whole grains, beans and low-fat dairy, poultry, fish and meats. People with PAD often have elevated cholesterol levels and high blood pressure, both of which can be controlled with a healthy diet.
• Reach and maintain a healthy weight.
• Keep good control of your blood glucose levels, if you have diabetes.

Facts to Know

1. Peripheral arterial disease (PAD) is primarily caused by atherosclerosis, or hardening of the arteries.
2. According to the Centers for Disease Control and Prevention, 12 percent to 20 percent of people over 60 may suffer from PAD. Unfortunately, many of them consider PAD's leg pain as simply part of getting older and don't get treatment.
3. PAD is associated with a high short-term risk of heart attack and stroke and a very low risk of development of non-healing wounds, gangrene and amputation.
4. For most individuals with claudication, a program of supervised exercise may be all that is required to improve the symptoms of PAD. Regular exercise is the most consistently effective treatment of PAD because it reconditions weakened muscles, helps decrease buildup of cholesterol, improves blood pressure, improves diabetes control, assists in weight-loss efforts and helps maintain healthy circulation.
5. Smoking is the single most important risk factor for PAD because many components of tobacco directly damage the artery.
6. Unfortunately, many people with symptoms of PAD don't report them. Therefore, a large number of people with the condition go untreated.
7. People with PAD often have elevated cholesterol levels and high blood pressure, which can be brought under control through diet and medications.
8. There are several medications that can help you achieve your PAD treatment goals. The risk of heart attack and stroke can be reduced with aspirin and medications that reduce blood pressure and cholesterol levels and improve diabetic control. Other medications can improve the symptoms of claudication by helping blood reach the leg muscles despite arterial blockages.
9. If exercise and medications aren't effective in improving claudication, the symptoms can sometimes be treated with nonsurgical procedures that involve only a small nick in the skin and the use of small balloon-tipped catheters (tubes) under X-ray guidance to open arteries. Specialized physicians perform these procedures, which usually require only an overnight stay in the hospital and little recuperation time.
10. Surgery, in which closed arteries are bypassed, is rarely required but may be an option if there is a risk of amputation, or if all other exercise, medication and angioplasty options are ineffective or are not feasible.

Questions to Ask

Review the following Questions to Ask about peripheral arterial disease so you're prepared to discuss this important health issue with your health care professional.

1. Do my symptoms indicate that I have peripheral arterial disease (PAD)? If so, how severe is my condition? What is my ankle-brachial index (ABI)?
2. Can my PAD be controlled with lifestyle changes, such as exercise?
3. Can you prescribe a supervised exercise program?
4. What medications might help me reduce my risk of heart attack and stroke?
5. What medications might help me reduce my symptoms of claudication?
6. If medications are prescribed, what are the side effects?
7. How will any of these PAD medications interact with any other medications I'm taking or other medical conditions I have or might have?
8. What are the risks and benefits of the various treatment options suitable for me? Have you offered me all of the choices for treating my claudication?
9. How should I take care of my feet?
10. Is there evidence of blocked arteries (atherosclerosis) in other parts of my body, and what is my personal risk of heart attack and stroke?
11. If I am at a high risk for a heart attack or stroke, how can I prevent them?

Key Q&A

Organizations and Support

For information and support on coping with Peripheral Arterial Disease, please see the recommended organizations and Spanish-language resources listed below.

American Heart Association (AHA)
Website: https://www.americanheart.org
Address: 7272 Greenville Avenue
Dallas, TX 75231
Hotline: 1-800-AHA-USA-1 (1-800-242-8721)
Email: Review.personal.info@heart.org

National Heart, Lung, and Blood Institute (NHLBI) - NHLBI Health Information Center
Website: https://www.nhlbi.nih.gov
Address: Attention: Website
P.O. Box 30105
Bethesda, MD 20824
Phone: 301-592-8573
Email: nhlbiinfo@nhlbi.nih.gov

Vascular Cures
Website: https://vascularcures.org
Address: 274 Redwood Shores Parkway, #717
Redwood City, CA 94065
Phone: 650-368-6022
Email: info@vascularcures.org

Spanish-language resources

Medline Plus: Peripheral Arterial Disease
Website: https://www.nlm.nih.gov/medlineplus/spanish/peripheralarterialdisease.html
Address: Customer Service
8600 Rockville Pike
Bethesda, MD 20894
Email: custserv@nlm.nih.gov