The Importance of ABI (Ankle Brachial Index)
March 3, 2026
Ankle-Brachial Index (ABI) is a vital diagnostic tool in the field of vascular medicine, providing essential information for the assessment, diagnosis, and management of peripheral arterial disease (PAD). PAD is a common circulatory problem characterized by narrowed arteries, which reduce blood flow to the limbs, primarily affecting the legs. The ABI test measures the ratio of blood pressure at the ankle to the blood pressure in the arm, providing a non-invasive and cost-effective means of identifying PAD in patients (Aboyans et al., 2012).
The importance of ABI lies in its role in early PAD detection, risk stratification, and monitoring the effectiveness of therapeutic interventions. PAD often remains asymptomatic or underdiagnosed due to its subtle presentation, leading to significant morbidity and mortality (Fowkes et al., 2013). Accurate and timely PAD diagnosis using ABI allows for appropriate management, preventing disease progression and reducing the risk of severe complications, such as critical limb ischemia, amputation, and cardiovascular events (Gerhard-Herman et al., 2017). Numerous studies have reported that the ABI when compared to angiography has a sensitivity of more than 90% and a specificity of more than 95% in diagnosing 50% stenosis of the lower extremity arteries.
Furthermore, ABI has been demonstrated as an independent predictor of cardiovascular risk, as it correlates with the severity of atherosclerosis (Criqui et al., 1992). Patients with abnormal ABI values are at an increased risk of myocardial infarction, stroke, and cardiovascular-related death (Resnick et al., 2004). As a result, incorporating ABI into routine vascular assessment enables physicians to identify patients at high risk of cardiovascular events, guiding treatment decisions and facilitating early intervention.
ABI plays a crucial role in vascular medicine by facilitating early PAD diagnosis, stratifying cardiovascular risk, and guiding clinical management. The utilization of ABI allows physicians to improve patient outcomes, prevent complications, and reduce the burden of PAD and associated comorbidities.
References:
Aboyans, V., Criqui, M. H., Abraham, P., Allison, M. A., Creager, M. A., Diehm, C., … & Hirsch, A. T. (2012). Measurement and interpretation of the ankle-brachial index: a scientific statement from the American Heart Association. Circulation, 126(24), 2890-2909.
Criqui, M. H., Langer, R. D., Fronek, A., Feigelson, H. S., Klauber, M. R., McCann, T. J., & Browner, D. (1992). Mortality over a period of 10 years in patients with peripheral arterial disease. New England Journal of Medicine, 326(6), 381-386.
Fowkes, F. G., Rudan, D., Rudan, I., Aboyans, V., Denenberg, J. O., McDermott, M. M., … & Cr iqui, M. H. (2013). Comparison of global estimates of prevalence and risk factors for peripheral artery disease in 2000 and 2010: a systematic review and analysis. The Lancet, 382(9901), 1329-1340.
Gerhard-Herman, M. D., Gornik, H. L., Barrett, C., Barshes, N. R., Corriere, M. A., Drachman, D. E., … & Regensteiner, J. G. (2017). 2016 AHA/ ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary. Vascular Medicine, 22(3), NP1-NP43.
Resnick HE, Lindsay RS, McDermott MM, Devereux RB, Jones KL, Fabsitz RR, Howard BV. Relationship of high and low ankle brachial index to all-cause and cardiovascular disease mortality: the Strong Heart Study. Circulation. 2004 Feb 17;109(6):733-9. doi: 10.1161/01. CIR.0000112642.63927.54. PMID: 14970108.