Competing Risk Analysis of the Impact of Pedal Arch Status and Angiosome-Targeted Revascularization in Chronic Limb-Threatening Ischemia

Abstract

In the context of chronic limb-threatening ischemia, the prognostic impact of angiosome-targeted revascularization and of the status of the pedal arch are debated. This series includes 580 patients who underwent endovascular (n=407) and surgical revascularization (n=173) of the infrapopliteal arteries for chronic limb-threatening ischemia associated with foot ulcer or gangrene. The risk of major amputation after infrapopliteal revascularization was assessed by a competing risk approach. A subanalysis was made separately for patients who underwent endovascular or open surgical revascularization. At 2years, survival was 65.1% and leg salvage was 76.1%. Multivariable competing risk analysis showed that C-reactive protein ≥10mg/dL, diabetes, rheumatoid arthritis, increased number of affected angiosomes, and the incomplete or total absence of pedal arch compared with complete pedal arch (CPA) were independent predictors of major amputation after infrapopliteal revascularization. Multivariable analysis showed increasing risk estimates of major amputation in patients with incomplete (subdistribution hazard ratio [SHR], 2.131; 95% confidence interval [95% CI], 1.282-3.543) and no visualized pedal arch (SHR, 3.022; 95% CI, 1.553-5.883) compared with CPA. Pedal arch was important even if angiosome-targeted revascularization was achieved: Angiosome-directed revascularization in presence of CPA had a lower risk of major amputation (adjusted SHR, 0.463; 95% CI, 0.240-0.894) compared with angiosome-directed revascularization without CPA. In the subanalysis, among patients who underwent endovascular revascularization, CPA (SHR, 0.509; 95% CI, 0.286-0.905) and angiosome-targeted revascularization (SHR, 0.613; 95% CI, 0.394-0.956) were associated with a lower risk of major amputation. Competing risk analysis showed that a patent pedal arch had significant impact on leg salvage and that the subset of patients undergoing endovascular procedure may most benefit of an angiosome-targeted revascularization.