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Ankle-Brachial Index (ABI)

The ankle-brachial index (ABI) test is a quick, noninvasive way to check for peripheral artery disease (PAD).

The ankle-brachial index test compares the blood pressure measured at the ankle with the blood pressure measured at the arm. A low ankle-brachial index number can indicate narrowing or blockage of the arteries in the legs.

How does it work?

Typically, the patient lies on a table on his or her back, and a technician measures blood pressure in both arms and both ankles, using an inflatable cuff and a hand-held ultrasound device that’s pressed to the skin. The device uses sound waves to produce images and allows the pulse to be heard in the ankle arteries after the cuff is deflated.

Am I a good candidate for treatment?

Patients should consider ankle-brachial index testing if they have leg pain while walking or risk factors for PAD, such as:

  • History of tobacco use
  • Diabetes
  • High blood pressure
  • High cholesterol
  • Restricted blood flow (atherosclerosis) in other parts of the body

What can I expect after treatment?

A Deborah Specialty Physician will use the blood pressure measurements from both the arms and ankles to calculate ankle-brachial index.

Based on the number, the ABI may show:

  • No blockage (1.0 to 1.4)
  • Borderline blockage (0.91 to 0.99)
  • PAD (less than 0.90)

Depending on the severity of the blockage, the physician may recommend:

  • Lifestyle changes
  • Medication
  • Surgery to treat PAD