Your doctor will review your personal risk factors for atherosclerosis and your family history. Your doctor will ask if you or any family members have heart disease, high cholesterol, diabetes, kidney disease, high blood pressure or any other circulation disorder. During the physical examination, your doctor will feel the pulse in your upper leg (near the groin), on the inside of your ankle, the top of your foot and the back of your knee. Any weakness in a pulse may be a sign of narrowed arteries.
Usually the doctor can diagnose peripheral arterial disease based on your symptoms, risk factors, the examination of your legs and the strength of your pulses. Your doctor may measure the blood pressure in your legs and compare it to the blood pressure in your arm to calculate the ankle-brachial index, or ABI. The ratio the blood pressure measured at your ankle is compared to the blood pressure measured at your elbow. Normally blood pressure is the same or a little higher in the legs so the ratio is 1.0 or higher.
A ratio of less than 0.95 in either leg indicates narrowing of the arteries in that leg. People who have symptoms of peripheral arterial disease usually have a ratio of 0.8 or less.
Your doctor may order ultrasound of the legs to measure blood flow. The test is non-invasive and painless, using sound waves to create the pictures. If your doctor suspects that you need a procedure to help open a blocked blood vessel, you may need a magnetic resonance imaging (MRI) scan of your arteries or an angiogram, which is an X-ray test that uses dye in the narrowed arteries to reveal the pattern of blood flow and spot blockages.