What is Ankle Brachial Index (ABI) technology?

Before we get into the specifics of how  and ankle brachial index works and dive into the various interpretation of its results, we need to first understand what ankle brachial index refers to.

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The ankle brachial index study, simply put, is a vascular study used primarily to diagnose Peripheral Arterial Disease. A non-invasive vascular testing equipment — an ABI Doppler Ultrasound Machine — is used to measure a patient’s systolic pressures at the arm and the ankle. The ankle brachial index is then determined by calculating the ratio of these two systolic pressures. 

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In other words, the ankle brachial index is the systolic pressure of a patient at the ankle divided by the systolic pressure at the arm. Based on this index, the potential and the severity of peripheral vascular disease in a patient is determined.

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It might sound rather weird that a test of your ankle could help predict threatening cardio-vascular diseases. However, ABI vascular test is not only possible but also crucial as it helps your doctor test the blood flow in your arteries and foresee threatening diseases.

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With a proper ABI ultrasound protocol in place, a team of doctors with the help of an ABI ultrasound machine and an ABI ultrasound CPT code conduct the test. During the process, the specialized ABI equipment bounces sound waves on the patient’s arteries to get their blood flow readings and transform those readings into images.

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The accuracy and comprehensiveness of the ankle brachial index test have made it the most popular cardiovascular examination method and the most specific metric in diagnosing peripheral vascular diseases and arterial stress.

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Furthermore, the ankle brachial index also helps identify the extent of damage from the disease, especially how it might be affecting a patient’s extremities. The index does have its limitations, though. For instance, the test doesn’t show where or how severe the blockage is.

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Before we understand how ABI helps diagnose PAD, let’s have a look at PAD is and what causes it.

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Essentially, the buildup of plaque in a person’s arteries leads to blockage in regular blood flow. The arteries carrying blood to the arms, stomach, aorta, kidneys and brain could be blocked. The arteries inside the heart could harden from the plaque leading to a cardiovascular condition called coronary artery disease.

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This can also be done using ABI Test.

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Depending on the extent of the blockage to the peripheral arteries, the severity of PAD is determined. In case of PAD, the narrowing of the arteries could lead to the occlusion of a patient’s legs.

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PAD is not the only cardiovascular disease that ankle brachial index helps predict. The index is also used to predict adverse cardiovascular events with non-traditional risk factors.