Abstract
OBJECTIVES: Data evaluating outcomes among patients with single-vessel tibial runoff are limited. Our aim was to compare outcomes across patients with sole anterior tibial (AT), peroneal, or posterior tibial (PT) runoff following revascularization for chronic limb-threatening ischemia (CLTI), and to evaluate whether the quality of peroneal communicating branches affects outcome risk within the peroneal runoff population.
METHODS: All patients undergoing first-time revascularization for CLTI were retrospectively reviewed (2005-2022) and stratified by sole runoff vessel (AT, peroneal, PT). Primary outcomes were wound healing, major amputation, major adverse limb events (MALE), and amputation/death, assessed by Kaplan-Meier analysis and multivariable Cox regression. A subset analysis stratified single-vessel peroneal runoff patients into a three-tiered, Peroneal Communicating Branch (PCB) Grade: Both branches present with at least one robust (PCB Grade 1), a single robust branch (PCB Grade 2), or no robust branch (PCB Grade 3), and compared each to the single-vessel AT/PT reference group.
RESULTS: Overall, 732 patients had single-vessel below-knee runoff: 225 AT, 315 peroneal, and 192 PT. Groups differed significantly in age, sex, and diabetes prevalence. Unadjusted two-year major amputation rates were significantly higher in the peroneal group (19% vs. 9.4% [AT] vs. 8.7% [PT]; P<.001), as were MALE rates (30% vs. 14% vs. 26%; P=.01). After adjustment, peroneal runoff was independently associated with higher risk of major amputation (HR 1.81 [1.04-3.13]) and MALE (HR 1.52 [1.03-2.25]) compared with AT/PT runoff. These associations persisted in the endovascular cohort (major amputation: HR 2.09 [1.06-4.13]; MALE: HR 1.59 [1.08-2.35]) but did not reach significance in the bypass cohort, which was limited by low event rates. When patients with single-vessel peroneal runoff were stratified by PCB Grades, unadjusted one-year major amputation rates followed a clear anatomically-driven pattern (6.9% (AT/PT) vs. 5.4% (PCB Grade 1) vs. 15% (PCB Grade 2) vs. 32% (PCB Grade 3); P<.001). After adjustment, when compared to AT/PT runoff, patients without any robust branch (PCB Grade 3) had significantly higher risk of major amputation (HR 3.21 [1.76-4.84]) and MALE (HR 2.41 [1.53-3.79]), while those with two branches with at least one being robust (PCB Grade 1) demonstrated higher rates of complete wound healing (HR 1.69 [1.09-2.62]) and no difference in major amputation or MALE.
CONCLUSIONS: Peroneal runoff is independently associated with worse limb outcomes following revascularization for CLTI, but this risk may be primarily driven by patients with absent or diminutive communicating branches. Those with robust branching demonstrate outcomes comparable to AT/PT runoff, underscoring the importance of further evaluation and pre-operative assessment of peroneal communicating branch quality - using the proposed PCB Grading system - in revascularization planning.
