Peripheral artery disease (PAD) refers to diseases of the blood vessels located outside the heart and brain. They are most often caused by a buildup of fatty deposits in the arteries. PAD is also known as peripheral arterial disease or peripheral vascular disease (which includes both arteries and veins).
PAD affects the blood vessels causing them to narrow, therefore restricting the blood flow to the arms, kidneys, stomach, and most commonly, the legs.
An estimated 8.5 million people in the United States have peripheral artery disease, affecting approximately 12-20 percent of Americans over 60.
Peripheral artery disease is a major risk factor for heart attack and stroke. PAD is more common in African-Americans than other racial groups; and men are slightly more likely than women to develop PAD. Peripheral vascular disease is also more common in smokers.
Although the condition can have serious consequences, physical activity can substantially improve symptoms.
Fast facts on peripheral artery disease
- The best way to prevent PAD is by taking part in physical activity.
- The most common cause is a build-up of cholesterol in the arteries.
- Peripheral artery disease is a risk factor for more serious cardiac events.
- Symptoms of PAD include numbness and pain in the legs.
Experts say that around half of all people with PAD do not know they have the condition; this is because many individuals have no symptoms. Possible symptoms include:
- Hair loss on the feet and legs.
- Intermittent claudication - the thigh or calf muscles may feel pain when walking or climbing stairs; some individuals complain of painful hips.
- Leg weakness.
- A foot or the lower leg may feel cold.
- Numbness in the legs.
- Brittle toenails.
- Toenails grow slowly.
- Sores or ulcers on the legs and feet that take a long time to heal (or never heal).
- The skin on the legs becomes shiny or turns pale or bluish.
- Difficulty in finding a pulse in the leg or foot.
- Erectile dysfunction (impotence in men, problems achieving or sustaining an erection).
Less common causes of peripheral artery disease are blood clots in the arteries, injury to the limbs, and unusual anatomy of the muscles and ligaments.
Risk factors that contribute to PAD are diabetes, smoking, obesity, high blood pressure, increasing age, high cholesterol, family history of heart disease, and excess levels of C-reactive protein or homocysteine.
There are several ways PAD can be diagnosed, if the disease is suspected, the doctor will initially check the patient's legs.
- Ankle-brachial index - the most common test for PAD, it is a test that compares the blood pressure in the ankle with the blood pressure in the arm.
- Ultrasound scan, angiography, and blood tests - may also be recommended to check levels of cholesterol, homocysteine, and C-reactive protein.
- Doppler and ultrasound (Duplex) imaging - a non-invasive method that visualizes the artery with sound waves and measures the blood flow in an artery to indicate the presence of a blockage.
- Computed tomographic angiography (CT) - another non-invasive test that images the arteries of a patient's abdomen, pelvis, and legs. This test is particularly useful in patients with pacemakers or stents.
- Magnetic Resonance Angiography (MRA) - gives similar information to that generated by a CT scan, but without the need for X-rays.
- Angiography - this is normally reserved for use in conjunction with vascular treatment procedures. During an angiogram, a contrast agent is injected into the artery and X-rays are taken to show blood flow and to pinpoint any blockages that may be present.
Undiagnosed or untreated PAD can be dangerous; it can lead to painful symptoms, loss of a leg, increased risk of coronary artery disease, and carotid atherosclerosis (a narrowing of the arteries that supply blood to the brain).
Because people with PAD have an increased risk of heart attack and stroke, the American Heart Association encourages people at risk to discuss PAD with their doctor to ensure early diagnosis and treatment.
The American College of Cardiology Foundation and the American Heart Foundation (ACCF/AHA) collaborated to create the "2011 ACCF/AHA Focused Update of the Guideline for the Management of Patients With Peripheral Artery Disease (Updating the 2005 Guideline)." They published the document in the journal Circulation.
Regular physical activity - this is the most effective treatment, a doctor will often recommend a program of supervised exercise training. The patient may have to start off slowly. Simple walking regimens, leg exercises, and treadmill exercise programs three times a week can result in decreased symptoms in just 4-8 weeks.
Diet changes and adjustments - many individuals with PAD have elevated cholesterol levels. A diet low in saturated fat, trans fat, and cholesterol, as well as plenty of fruit and vegetables, can help lower blood cholesterol levels.
Smoking cessation - tobacco smoke greatly increases the risk of PAD, heart attack, and stroke. Smokers may have four times the risk of developing PAD than nonsmokers. Stopping smoking will help to slow the progression of PAD and other heart-related diseases.
Some medications - the doctor may prescribe antihypertensive drugs as well as statins to lower cholesterol levels. Cilostazol and pentoxifylline may be recommended for patients with intermittent claudication. The ACE inhibitor - ramipril - was shown to improve pain-free walking by 60 percent in a study published in JAMA.
Exercise for intermittent claudication must take into account the fact that walking can be painful. The program consists of alternating between activity and resting.
If the treatments mentioned above do not help enough, the doctor may advise angioplasty - the surgical unblocking or repair of a blood vessel.
Addressing the following risk factors can help prevent or delay PAD:
- Family history - if you or someone in your family has or had periphery artery disease, be sure to tell your doctor.
- Smoking - smoking is more closely related to developing heart disease than any other risk factor. Regular smokers are four times as likely to develop PAD than lifetime non-smokers. Talk to a doctor about programs and products that can help you quit smoking.
- Diet - follow a healthy eating plan that is low in total fat, saturated fat, trans fat, cholesterol, and sodium. Eat plenty of fruits, vegetables, and low-fat dairy products. Overweight and obese patients should work with a doctor to create a reasonable weight-loss plan.
PAD increases the risk of heart attack and stroke, so it is vital that it is diagnosed as soon as possible. Outlook depends on a range of factors, but following the lifestyle advice above improves outlook significantly.
Some cases of PAD can be managed by lifestyle changes and medication alone.