How Is Peripheral Arterial Disease Diagnosed?

Peripheral arterial disease (P.A.D.) is diagnosed based on your medical and family histories, a physical exam, and test results.

P.A.D. often is diagnosed after symptoms are reported. A correct diagnosis is important because people who have P.A.D. are at higher risk for coronary heart disease (CHD), heart attack, stroke, and transient ischemic attack ("mini-stroke"). If you have P.A.D., your doctor also may want to check for signs of these diseases and conditions.

Specialists Involved

Primary care doctors, such as internists and family doctors, may treat people who have mild P.A.D. For more advanced P.A.D., a vascular specialist may be involved. This is a doctor who specializes in treating blood vessel diseases and conditions.

A cardiologist also may be involved in treating people who have P.A.D. Cardiologists treat heart problems, such as CHD and heart attack, which often affect people who have P.A.D.

Medical and Family Histories

Your doctor may ask:

• Whether you have any risk factors for P.A.D. For example, he or she may ask whether you smoke or have diabetes.
• About your symptoms, including any symptoms that occur when walking, exercising, sitting, standing, or climbing.
• About your diet.
• About any medicines you take, including prescription and over-the-counter medicines.
• Whether anyone in your family has a history of heart or blood vessel diseases.

Physical Exam

During the physical exam, your doctor will look for signs of P.A.D. He or she may check the blood flow in your legs or feet to see whether you have weak or absent pulses.

Your doctor also may check the pulses in your leg arteries for an abnormal whooshing sound called a bruit (broo-E). He or she can hear this sound with a stethoscope. A bruit may be a warning sign of a narrowed or blocked artery.

Your doctor may compare blood pressure between your limbs to see whether the pressure is lower in the affected limb. He or she also may check for poor wound healing or any changes in your hair, skin, or nails that may be signs of P.A.D.

Diagnostic Tests

Ankle-Brachial Index

A simple test called an ankle-brachial index (ABI) often is used to diagnose P.A.D. The ABI compares blood pressure in your ankle to blood pressure in your arm. This test shows how well blood is flowing in your limbs.

ABI can show whether P.A.D. is affecting your limbs, but it won't show which blood vessels are narrowed or blocked.

A normal ABI result is 1.0 or greater (with a range of 0.90 to 1.30). The test takes about 10 to 15 minutes to measure both arms and both ankles. This test may be done yearly to see whether P.A.D. is getting worse.

Ankle-Brachial Index

The illustration shows the ankle-brachial index test. The test compares blood pressure in the ankle to blood pressure in the arm. As the blood pressure cuff deflates, the blood pressure in the arteries is recorded.

Doppler Ultrasound

A Doppler ultrasound looks at blood flow in the major arteries and veins in the limbs. During this test, a handheld device is placed on your body and passed back and forth over the affected area. A computer converts sound waves into a picture of blood flow in the arteries and veins.

The results of this test can show whether a blood vessel is blocked. The results also can help show the severity of P.A.D.

Treadmill Test

A treadmill test can show the severity of symptoms and the level of exercise that brings them on. You'll walk on a treadmill for this test. This shows whether you have any problems during normal walking.

You may have an ABI test before and after the treadmill test. This will help compare blood flow in your arms and legs before and after exercise.

Magnetic Resonance Angiogram

A magnetic resonance angiogram (MRA) uses magnetic and radio wave energy to take pictures of your blood vessels. This test is a type of magnetic resonance imaging (MRI).

An MRA can show the location and severity of a blocked blood vessel. If you have a pacemaker, man-made joint, stent, surgical clips, mechanical heart valve, or other metallic devices in your body, you might not be able to have an MRA. Ask your doctor whether an MRA is an option for you.

Arteriogram

An arteriogram provides a "road map" of the arteries. Doctors use this test to find the exact location of a blocked artery.

For this test, dye is injected through a needle or catheter (tube) into one of your arteries. This may make you feel mildly flushed. After the dye is injected, an x ray is taken. The x ray can show the location, type, and extent of the blockage in the artery.

Some doctors use a newer method of arteriogram that uses tiny ultrasound cameras. These cameras take pictures of the insides of the blood vessels. This method is called intravascular ultrasound.

Blood Tests

Your doctor may recommend blood tests to check for P.A.D. risk factors. For example, blood tests can help diagnose conditions such as diabetes and high blood cholesterol.