Ankle-Brachial Index (ABI)
Aboyans 2012 (AHA scientific statement) / 2016 AHA-ACC PAD guidelineDivides the higher ankle systolic pressure of each leg by the higher brachial systolic pressure to diagnose and grade peripheral artery disease; flags non-compressible vessels above 1.40.
Also searched as: peripheral artery disease · PAD · vascular lab · Doppler · ankle pressure · peripheral artery · claudication
Information
Incomplete input
- Please provide: at least one brachial systolic pressure.
How this tool works
For each leg the ABI is the higher of the dorsalis pedis and posterior tibial systolic pressures divided by the higher of the two brachial systolic pressures. An index of 1.00-1.40 is normal, 0.91-0.99 borderline, and 0.90 or less is abnormal and diagnostic of PAD — graded mild (0.70-0.90), moderate (0.40-0.69), or severe (below 0.40). An ABI above 1.40 indicates non-compressible, medially calcified arteries (typical in diabetes and chronic kidney disease), in which case a toe-brachial index should be measured (TBI of 0.70 or less is abnormal).
References
- Aboyans V, et al. AHA scientific statement: measurement and interpretation of the ABI. Circulation 2012;126:2890-2909
- Gerhard-Herman MD, et al. 2016 AHA/ACC PAD guideline. Circulation 2017;135:e726-e779
Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.
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