Peripheral Vascular Testing

An ankle-brachial index (ABI) test is used to compare blood pressure in your arm to blood pressure in your leg. Cuffs will be placed on your arms and ankles and then inflated. A transducer, or ultrasound device, uses high-frequency sound waves to measure blood pressure in both areas.

Your ankle pressure is divided by arm pressure, creating the ABI ratio. If your value is in the normal range (1.0 to 1.4), then blood pressure at your ankle is the same or greater than the blood pressure at your arm, and you are not at risk for PAD.

If the ABI ratio is 0.9 or lower, this typically indicates a blockage of blood flow in your leg arteries. A value higher than 1.4 may mean that you have rigid arteries that don't compress when the blood pressure cuff is inflated, and further testing may be required for an accurate diagnosis.

Doppler ultrasound is a non-invasive test method that uses high-frequency sound waves to show how blood moves through your arteries and veins. The images are transmitted to a monitor where any abnormalities such as blood clots, narrowed blood vessels, or backward-flowing blood can be detected.