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 results from tests.

P.A.D. often is diagnosed after symptoms are reported. An accurate diagnosis is important, because people who have P.A.D. are at increased risk for coronary artery disease (CAD), heart attack, stroke, and transient ischemic attack (“mini-stroke”). If you have P.A.D., your doctor also may want to look for signs of these conditions.

Specialists Involved

Primary care doctors, such as internists and family practitioners, 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 problems.

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

Medical and Family Histories

To learn about your medical and family histories, your doctor may ask:

• Whether you have any risk factors for P.A.D.
• 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 cardiovascular disease

Physical Exam

During the physical exam, your doctor will look for signs and symptoms 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 section of artery.

During the physical exam, 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) is often 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 ABI test. The ABI compares blood pressure in the ankle to blood pressure in the arm. As the cuff deflates, the blood pressure in the arteries is recorded.

Doppler Ultrasound

A Doppler ultrasound is a test that uses sound waves to show whether a blood vessel is blocked. This test uses a blood pressure cuff and special device to measure blood flow in the veins and arteries of the limbs. A Doppler ultrasound can help find out how severe P.A.D. is.

Treadmill Test

A treadmill test can show how severe your symptoms are and what level of exercise brings them on. For this test, you walk on a treadmill. This shows whether you have any problems during normal walking.

You may have an ABI test done 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 blood vessels inside your body. An MRA is a type of magnetic resonance imaging (MRI).

An MRA can find the location of a blocked blood vessel and show how severe the blockage is.

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. It’s used to find the exact location of a blocked artery.

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

Some hospitals use a newer method of arteriogram that uses tiny ultrasound cameras that 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, you may get a blood test to check for diabetes. You may also get a blood test to check your cholesterol levels.