What is an ankle-brachial index test?
The ankle-brachial index test is a painless exam that is used to diagnose peripheral arterial disease. The ankle-brachial index test compares blood flow in the ankles and arms, detecting poor circulation that can be caused by fatty plaque buildup. During the ankle-brachial index test, inflatable cuffs are used on your arms and ankles to measure your blood pressure. Once the cuffs are deflated, a Doppler ultrasound is also used on your ankle to listen to your arteries. To determine the ankle-brachial index, the systolic blood pressure (the top number of a blood pressure reading) of the ankle is divided by the systolic blood pressure of the arm. The simple ankle-brachial index test takes less than 15 minutes to perform at a physician’s office.
- Pain in your calves, thighs, hips or buttocks
- Symptoms that worsen with activity and are relieved with rest
What to expect during an ankle-brachial index test
- Ankle-brachial index of 1.0 or greater: Your blood flow is in normal range.
- Ankle-brachial index of 0.5 – 0.9: These results fall into the abnormal category. Depending on your test results, your physician may prescribe medications or order additional testing. You may also be referred to a vascular specialist.
- Ankle-brachial index of less than 0.5: This range indicates severe peripheral artery disease. Your physician will determine additional diagnostic measures and medications.