Bypass Versus Endovascular Therapy in Chronic Limb Threatening Ischemia Requiring Infra-Popliteal Interventions.

Objectives: Chronic Limb Threatening Ischemia (CLTI) involving the crural arteries is clinically and anatomically challenging. The BASIL-2 trial and a sub-analysis of the BEST-CLI trial examined the efficacy of endovascular therapy (EVT) versus surgical bypass (BP) among this cohort, but arrived at differing conclusions. This study aimed to compare the outcomes of EVT and surgical bypass among patients with CLTI requiring infra-popliteal interventions in a real-world registry.

Methods: All infra-popliteal procedures performed for CLTI were identified in the peripheral vascular intervention and infra-inguinal bypass registries of the Vascular Quality Initiative (VQI) from 2017-2022. 19,505 EVT and 9,185 BP were identified with significantly different risk profiles. Propensity score-matched cohorts were constructed to compare EVT versus BP, BP with autologous vein (BPAV), and BP with prosthetic conduit (BPPC). Amputation-free survival (AFS), overall survival (OS), and freedom from major amputation were examined.

Results: 5,236 well-matched pairs of EVT vs BP, 3,892 well-matched pairs of EVT vs BPAV, and 1,971 well-matched pairs of EVT vs BPPC were included. BP and EVT demonstrated equivalent AFS (two-year AFS: 50.3% vs 49.0%, HR amputation/death: 0.947 [0.876-1.024], P=0.229), which was due to superior OS in the BP group (two-year OS: 79.7% vs 75.6%, HR all-cause mortality: 0.841 [0.761-0.928] P=0.002) matched by inferior limb salvage in the BP group (two-year freedom from major amputation: 71.4% vs 81.4%, HR major amputation: 1.432 [1.266-1.620], P<0.001). BPAV, composed primarily (91%) of great saphenous vein bypass (GSV BP), was associated with significantly greater AFS than EVT (two-year AFS: 53.9% vs 52.5%, HR amputation/death: 0.854 [0.778-0.938], P<0.001), which was driven by greater OS (two-year OS: 81.1% vs 77.4%, HR all-cause mortality: 0.872 [0.776-0.980], P=0.015) with equivalent limb salvage (two-year freedom from major amputation: 76.0% vs 81.4%, HR major amputation: 1.102 [0.951-1.278], P=0.353). However, BPPC was associated with significantly lower AFS than EVT (two-year AFS: 44.1% vs 46.9%, HR amputation/death: 1.279 [1.126-1.452], P=0.001), which was driven inferior limb salvage in the BPPC group (two-year freedom from major amputation: 63.3% vs 77.5%, HR major amputation: 2.165 [1.780-2.633], P<0.001) despite higher OS in the BPPC group (two-year OS: 78.8% vs 75.8%, HR all-cause mortality: 0.837 [0.706-0.992], P=0.012).

Conclusion: When feasible, BPAV (particularly with GSV) should be considered over EVT due to superior AFS and OS with equivalent limb salvage. However, when autologous vein is unavailable, an aggressive approach to EVT may be warranted due to superior AFS and limb salvage despite slightly higher OS in the BPPC group.