Peripheral Artery Disease and Intermittent Claudication
DescriptionAn in-depth report on the causes, diagnosis, and treatment of peripheral artery disease
Alternative NamesIntermittent Claudication
Evidence suggests that PAD is an important risk factor for heart disease and stroke but is greatly underdiagnosed. Many patients do not report symptoms or may not even have symptoms. People should be evaluated for peripheral artery disease if they have risk factors for heart disease, leg pain during walking, or ulcers on their legs.
The physician should evaluate the patient with a number of physical examinations for high blood pressure, heart abnormalities, blockage in the artery in the neck, and abdominal aneurysms. The physician will also examine the skin of the legs and feet for color changes, ulcers, infection, or injuries. The physician will also check the pulse of the arteries in the leg.
Doppler Ultrasound and Ankle-Brachial Index
Intermittent claudication caused by peripheral artery disease is typically diagnosed using a procedure called Doppler ultrasound and a calculation called the ankle-brachial index. This procedure is also proving to be important for diagnosing PAD even in patients without symptoms of intermittent claudication.
The procedure involves the following:
The physician divides the systolic pressure in the ankle by that in the arm. The result is called the ankle-brachial index (ABI), also called ankle-arm pressure index (API). The results suggest the following:
Computed Tomography Angiography
A new technology called computed tomography angiography (CTA) uses x-rays to visualize blood flow in arterial vessels throughout the body. This technique is highly effective in diagnosing PAD.
A patient is often given a treadmill test if the ankle-brachial index is questionable. Patients with claudication have a 50% to 60% reduction in peak performance, which is comparable to that in patients with congestive heart failure. The treadmill test is also useful for determining the severity of the pain while walking and for assessing the effectiveness of treatments.
A test called a wave form analysis may be used to confirm an abnormal API or pressure reading. The patient lies on his or her back for at least 10 minutes in a warm room (so that the blood vessels will not narrow). The leg is turned out and the knee is bent slightly. A probe is passed over the leg, which picks up sound waves coming from the arteries. These signals are recorded and the wave forms traced to detect abnormal blood flow.
Tests for Detecting Heart Disease
Patients with suspect PAD should have an electrocardiogram (ECG) and possibly other tests that would detect heart problems. Evidence suggests that heart disease may be underdiagnosed in these patients. In one study, for example, a third of patients had silent ischemia, which is heart disease without angina, the chest pain that indicates blockage of blood flow to the heart.
Ruling out Other Disorders with Similar Symptoms
A number of other tests can rule out disorders with similar symptoms, which include the following: