Ankle-brachial pressure index (ABPI) assesses peripheral vascular disease.

These pressures are called segmental blood pressures and are used to evaluate blockage or arterial occlusion in a limb (see Ankle brachial pressure index).

Upon suspicion of PVD, the first-line study is the ankle brachial pressure index (ABPI/ABI).

This concept explains why the arterial pressure inside the peripheral arteries of the legs and arms is higher than the arterial pressure in the aorta, and in turn for the higher pressures seen at the ankle compared to the arm with normal ankle brachial pressure index values.

Individuals with PAD have an "exceptionally elevated risk for cardiovascular events and the majority will eventually die of a cardiac or cerebrovascular etiology"; prognosis is correlated with the severity of the PAD as measured by the Ankle brachial pressure index (ABPI).