Utility of the Small Artery Disease Score on Lateral Foot Angiography in Patients with Chronic Limb-Threatening Ischemia

PURPOSE: To evaluate the utility of the small artery disease (SAD) score as a predictor of clinical outcomes and major adverse limb events (MALEs) in patients with chronic limb-threatening ischemia (CLTI), using lateral digital subtraction angiography (DSA) images. MATERIALS AND METHODS: A retrospective study was conducted in 183 patients with Fontaine 3 or 4 (mean age, 72.2 years [SD ± 12.1]; 132 men) who underwent lateral DSA of the foot between 2020 and 2022. Three independent observers assessed all lateral projections of the foot using the SAD score. Outcomes included wound healing, amputation, repeat revascularization, MALEs, and survival. RESULTS: Patients with an SAD score of ≥1 had a significantly increased risk for MALEs (hazard ratio [HR], 2.22; P = .011) and death (HR, 2.06; P = .025). There was no significant risk for impaired wound healing (HR, 1.15; P = .669) and amputation (HR, 1.48; P = .157) in patients with SAD score of ≥1. Interobserver agreement between the 3 observers for presence of SAD was substantial, with an intraclass correlation coefficient of 0.61 (95% confidence interval, 0.53-0.68). CONCLUSIONS: Presence of SAD increases the risk of MALE and death in patients with CLTI but had no relation with wound healing or amputation.