Lower Limb Peripheral Artery Disease Assessment via Ankle Brachial Index and CT Angiography

Abstract

Background: Peripheral arterial disease is common among patients with type 2 diabetes mellitus and may be difficult to assess because arterial calcification can alter ankle-brachial index interpretation. Objective: To determine the association between ankle-brachial index categories and CT angiographic findings in patients with suspected lower-limb peripheral arterial disease. Methods: This single-center cross-sectional observational study included 45 patients with type 2 diabetes mellitus and suspected lower-limb peripheral arterial disease. Demographic characteristics, cardiovascular risk factors, symptoms, limb involvement, ABI values, and CTA findings were recorded. CTA findings included arterial segment involvement, stenosis severity, and calcification. Associations between ABI category and CTA findings were analyzed using chi-square testing. Results: The study included 25 males and 20 females, with 62.2% aged 60 years or above. Bilateral limb involvement was present in 18 patients. Peroneal artery involvement was the most frequent CTA finding (44.4%), followed by tibial artery involvement (42.2%). ABI-defined PAD was significantly associated with CTA stenosis severity; 7 patients had mild stenosis, 15 had moderate stenosis, and 19 had severe or occlusive disease, while all 4 patients with ABI 0.90–1.30 had mild stenosis only (χ²=13.570, p=0.001). Non-compressible ABI was strongly associated with CTA-detected calcification (χ²=35.837, p<0.001). Conclusion: ABI is useful for functional screening of lower-limb PAD, but CTA provides essential anatomical confirmation, particularly in diabetic patients with non-compressible ABI and suspected calcification.