[Ankle-brachial index: a useful tool for stratifying cardiovascular risk].

All clinical guidelines on cardiovascular disease prevention recommend estimation of the overall individual risk as the basic tool to carry out an effective intervention. Unfortunately, the predictive power of risk equations and tables is not optimal, since many individuals who experience cardiovascular events are not identified as being at high-risk.1 For this reason, attempts have been made to improve risk estimation by direct detection of arteriosclerosis in various vascular regions through imaging. Several techniques are available for the diagnosis of subclinical arteriosclerosis, including magnetic resonance, electron beam computed tomography scanning, helical computed tomography, and echo-Doppler of the supraaortic vessels. Nevertheless, these techniques have important limitations, such as a limited accessibility, elevated cost, and the need for specialized personnel, all of which make their use in daily clinical practice impracticable.2 There is, however, a simple, low-cost, reproducible test performed in the physician’s office that is highly useful for the diagnosis of peripheral arterial disease (PAD) and for identifying individuals at a high risk of cardiovascular disease,3 namely, the ankle-brachial index (ABI). The ABI is calculated by dividing the systolic arterial pressure (SAP) of each ankle (choosing the highest value between the pedal artery and the posterior tibial artery) by the highest SAP value of either of the brachial arteries. Thus, 2 ABI values are obtained, one for each leg, and the lowest is selected as the definitive value. The test is short (an experienced professional can perform the technique in Ankle–Brachial Index: a Useful Tool for Stratifying Cardiovascular Risk