This test is done by measuring blood pressure at the ankle and in
the arm while a person is at rest. Measurements are usually repeated at both
sites after 5 minutes of walking on a treadmill.
The ankle-brachial index (ABI) result is used to predict the
peripheral arterial disease (PAD). A slight drop in
your ABI with exercise means that you probably have PAD. This drop may be
important, because PAD can be linked to a higher risk of heart attack or
In every issue of WebMD the Magazine, we ask our experts to answer readers' questions about a wide range of topics. In our September 2011 issue, we gave a reader's question about preventing heart disease to James Beckerman, MD, WebMD's heart health expert.
Q : Heart disease runs in my family. What can I really do now to help prevent it?
A : Cut out these five things to greatly reduce your risk:
Smoking (or hanging around with smokers). Smoking is the most dangerous -- yet most reversible...
This test is done to screen for peripheral arterial disease of the
legs. It is also used to see how well a treatment is working (such as medical
treatment, an exercise program, angioplasty, or surgery).
The ABI result can help diagnose peripheral arterial disease (PAD).
A lower ABI means you might have PAD. A slight drop in the ABI with exercise,
even if you have a normal ABI at rest, means that you probably have PAD.
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.1
An abnormal resting ankle-brachial index is 0.9 or lower. If the
ABI is 0.91 to 0.99, it is considered borderline abnormal.1
What To Think About
You may experience leg pain during the treadmill portion of the
test if you have peripheral arterial disease (PAD).
Undiagnosed arterial disease in the arms can cause inaccurate test
Blood pressure readings may not be accurate when the blood vessel
being measured is hardened by calcium (calcified). Arteries may calcify more
than usual if you have
diabetes or kidney problems (renal
A very abnormal ABI test result may require more testing to
determine the location and severity of PAD that might be present.
Rooke TW, et al. (2011). 2011 ACCF/AHA Focused update of the guideline for the management of patients with peripheral artery disease (Updating the 2005 guideline): A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Journal of the American College of Cardiology, 58(19): 2020–2045.
Primary Medical Reviewer
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
Specialist Medical Reviewer
David A. Szalay, MD - Vascular Surgery
October 18, 2011
WebMD Medical Reference from Healthwise
October 18, 2011
This information is not intended to replace the advice of a doctor.
Healthwise disclaims any liability for the decisions you make based on this