Ankle-Brachial Index Information

Peripheral artery disease is a condition that can increase a person's risk for developing heart complications, such as poor circulation, heart attack and stroke. This condition causes the arteries of the legs and ankles to become narrowed, decreasing proper blood flow. To diagnose this condition, an ankle-brachial index test is used. This test is an easy and non-invasive procedure to diagnose the condition.

This is a very simple test to undergo to assess a person's risk for an underlying health condition. The test measures the blood pressure taken from the arms and compares it with the blood pressure taken from a person’s ankle. The results from the test, will determine whether or not a person suffers from peripheral artery disease. If the blood pressure measurement taken from the ankle is lower than the measurement taken from the arm, than there is an indication the arteries of the legs may have narrowed.

Generally, there is no preparation needed for the test. To perform the ankle-brachial index test, the doctor will measure the blood pressure in both of the patient’s arms while they are laying flat on the doctors table. An inflatable cuff is used to measure the blood pressure.

Afterwards, the doctor measures the blood pressure of the left ankle using the inflatable cuff and a hand-held Doppler device. The blood pressure will be taken in the ankle in two separate positions.

This test is a painless procedure that does not pose any risks or complications. The procedure is very similar to blood pressure being taken during routine physical examinations.

Receiving the result from the test is very simple. The doctor will take the highest number of the blood pressure measurement from the arms and divide it by the highest measurement taken from the ankles. The number the doctor receives as a result will determine whether or not there is a blockage.

• 1.0 to 1.3: This is considered to be a normal reading with no apparent blockage in the arteries.
• 0.8 to 0.99: This result indicates a mild blockage with some narrowing of the arteries. The doctor is likely to continue monitoring for further progression of the disease.
• 0.5 to .79: A moderate blockage is present if this is the result of the test. A person with this progression of the condition may experience pain in the legs when exercising.
• Less than 0.5: This indicates a severe blockage. Pain may be present in the legs, even while resting.

Depending on the results of the test, a doctor may order more tests to be conducted and continue to monitor the situation.

“Ankle-Brachial Index” June 25, 2008 MayoClinic.com

“Ankle-Brachial Index Test” 2007 WebMD.com