Introduction: This physician-initiated study provides 5-year (i.e., long-term) treatment durability data from 3 top recruitment sites that participated in the prospective, multicenter, nonrandomized, single-arm VBX FLEX clinical study (ClinicalTrials.gov identifier: NCT02080871). It evaluates the long-term treatment durability of the GORE VIABAHN VBX Balloon Expandable Endoprosthesis (VBX Stent-Graft) in the treatment of subjects with de novo or restenotic aortoiliac lesions. Materials and Methods: A total of 59 subjects with 94 treated lesions were enrolled at the 3 participating sites from the original 140 intent-to-treat subjects in the VBX FLEX study. The primary durability endpoint was long-term primary patency. Secondary long-term outcomes included freedom from target lesion revascularization (TLR), freedom from target vessel revascularization (TVR), as well as resting ankle-brachial index (ABI), Rutherford category, EuroQol 5 Dimensions, and Walking Impairment status. Results: Fifty-nine subjects participated and twenty-eight (47.5%) were available through the end of the study at 5-year follow-up (the median follow-up time was 6.6 years due to complications resulting from COVID-19 precautions). At 3 and 5 years, the Kaplan-Meier estimates for freedom from all-cause mortality were 94.5% and 81.7%, respectively. The Kaplan-Meier estimates for primary patency at 3 and 5 years were 94.0% and 89.5% (by lesion) and 91.7% and 84.4% (by subject). Primary assisted patency at 3 and 5 years were 93.3% and 93.3%. Kaplan-Meier estimate for freedom from TLR at 5 years was 89.1%. The majority of subjects were asymptomatic (Rutherford category 0) at 3 years (29/59; 72%), and at 5-year follow-up (18/28; 64%). The 5-year mean resting ankle-brachial index was 0.95±0.18, an improvement of 0.15±0.26 from the baseline (p<0.001). Quality of life measures also showed sustained improvement through long-term follow-up. Conclusion: The 5-year long-term follow-up data underscore the robustness and durability of the Viabahn Balloon-Expandable Endoprosthesis for treating aortoiliac occlusive disease. Clinical Impact Durable improvement after endovascular treatment of iliac occlusive disease is clinically important because many of these patients are claudicants with significant life expectancy. This study is the first to evaluate the long-term outcomes in patients with iliac occlusive disease treated with the Viabahn VBX balloon-expandable endopirostheses. The study reports excellent long-term patency outcomes with prolonged clinical benefit. These durable results are likely to be an important consideration for clinicians undertaking iliac artery revascularization procedures.
