Ankle-Brachial Index Test
This test is done by measuring blood pressure at the ankle and in the arm while a person is at rest. Some people also have an exercise test. In this case, the blood pressure measurements are repeated at both sites after a few minutes of exercise, such as walking on a treadmill.
Why It Is Done
The test might be done to check your risk of heart attack and stroke.footnote 2 The results can help you and your doctor make decisions about how to lower your risk.
The ABI result can help diagnose peripheral arterial disease (PAD). The result can also be used to check your risk of a heart attack and stroke.
A normal resting ankle-brachial index is 1.0 to 1.4. This means that your blood pressure at your ankle is the same or greater than the pressure at your arm, and suggests that you do not have significant narrowing or blockage of blood flow.footnote 3
A lower ABI means you might have PAD. Abnormal values for the resting ankle-brachial index are 0.9 or lower and 1.40 or higher. If the ABI is 0.91 to 1.00, it is considered borderline abnormal.footnote 3
Abnormal values might mean you have a higher chance of having narrowed arteries in other parts of your body. This can increase your risk of a heart attack or stroke.
- Gerhard-Herman MD, et al. (2016). 2016 AHA/ACC guideline on the management of patients with lower extremity peripheral artery disease. Circulation, published online November 13, 2016. DOI: 10.1161/CIR.0000000000000471. Accessed November 25, 2016.
- Grundy SM, et al. (2018). 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline on the management of blood cholesterol: A report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines. Journal of the American College of Cardiology, published online November 8, 2018: S0735. DOI: 10.1016/j.jacc.2018.11.003. Accessed January 28, 2019.
- Aboyans V, et al. (2012). Measurement and interpretation of the ankle-brachial index: A scientific statement from the American Heart Association. Circulation, 126(24): 2890–2909.
Current as of: June 25, 2023