Sex-Stratified Outcomes of Drug-Eluting Resorbable Scaffolds Versus Balloon Angioplasty for Below-the-Knee Revascularization: Insights From the LIFE-BTK Trial.

BACKGROUND: Women with chronic limb-threatening ischemia remain historically underrepresented in peripheral artery disease trials and often exhibit distinct anatomic and clinical profiles. The LIFE-BTK randomized trial demonstrated superiority of an everolimus-eluting resorbable scaffold (DRS) over percutaneous transluminal angioplasty (PTA) for below-the-knee revascularization. This analysis assessed whether sex influenced baseline characteristics, procedural details, or clinical outcomes after DRS compared with PTA. METHODS: LIFE-BTK randomly assigned 261 patients (2:1 DRS/PTA) with Rutherford-Becker class 4-5 ischemia across 50 global sites. Sex-stratified outcomes at 1 and 2 years were evaluated using descriptive statistics, multivariate models, and Kaplan-Meier estimates. The primary efficacy end point was freedom from above-ankle amputation, target vessel occlusion, clinically-driven target lesion revascularization (CD-TLR), and binary restenosis. The primary safety end point was freedom from major adverse limb events and perioperative death. Both end points are presented here as event rates. RESULTS: Female patients (32% of cohort) were older and had smaller reference vessel diameters and lower ankle-brachial index values; male patients had higher tobacco use and cardiovascular comorbidities. At 1 year, DRS significantly reduced event rates for the primary efficacy end point vs PTA in both sexes (female: 23.5% vs 57.1%; male: 26.5% vs 56.0%). Benefits persisted at 2 years (female: 34.1% vs 68.4%; male: 40.7% vs 66.7%). Binary restenosis and CD-TLR were lower with DRS. Multivariate analysis showed sex was not significantly associated with outcomes, and no sex-by-treatment interaction was observed. Female patients demonstrated higher restenosis but lower CD-TLR rates, suggesting discordance between anatomic and clinical failure. CONCLUSIONS: DRS provided durable benefit over PTA irrespective of sex. Although sex did not modify treatment effect, differences in vessel size, ischemia severity, and restenosis-reintervention patterns highlight the need for sex-specific surveillance and personalized below-the-knee treatment strategies.