Testing for the Ankle Brachial Index
An ankle brachial index is a number used to diagnose peripheral artery disease (PAD). PAD is a condition that causes blood flow to your limbs to be limited due to narrowed arteries. It is important to diagnose PAD, because it is associated with a higher risk of having a heart attack.
How It Works
The ankle-brachial index testing procedure is quick, painless, and non-invasive, lasting only about 30 to 60 minutes. During the test, a technician will compare blood pressure measured at your arm with blood pressure measured at your ankle. If a low ankle-brachial index number is found, you may have narrowing or blocked arteries in the leg. The test can also be used to determine the severity of artery blockage while walking.
Test Results
When your doctor uses blood pressure measurements from the ankles and arms, your ankle-brachial index will be calculated. The following will be used to determine if issues are present:
- No blockage (1.0 to 1.4) If your ankle-brachial is between 1.0 and 1.4, it’s unlikely that you have PAD.
- Borderline Blockage (0.91 to 0.99) An ankle-brachial index between 0.91 and 0.99 indicates that minor blockage is present.
- Blockage (under 0.90) An ankle-brachial index under 0.90 indicates that you have abnormal blockage and you’ll be diagnosed with PAD.
This information is intended for general knowledge and educational purposes only, and does not constitute medical advice or a diagnosis of any medical condition. Consult a qualified healthcare professional for any health concerns or before making decisions related to your health or treatment.