Endovascular Therapy with Interwoven Nitinol Stent Placement after Predilation for Heavily Calcified Femoropopliteal Artery Disease: Results of the BURDOCK Study

Purpose: To investigate the 1-year and 2-year clinical outcomes of interwoven stent (IWS) implantation for symptomatic femoropopliteal arterial disease with calcification.Material and Methods: This prospective multicenter study evaluated 308 limbs (63% with the peripheral arterial calcium scoring system 3 and 4 severe calcification and 87% with >= 180(degrees) calcification on intravascular ultrasound) of 299 patients (diabetes in 66.9%, chronic renal failure in 52.8%, and dialysis in 49.2%) who underwent IWS (Supera; Abbott, Abbott Park, Illinois) implantation after sufficient predilation (residual stenosis < 30%) for calcified femoropopliteal lesions. The primary outcome measure was primary patency (freedom from restenosis) at 1 and 2 years, whereas the secondary outcome measure included freedom from clinically driven target lesion revascularization (CD-TLR). Clinical parameters associated with loss of patency were explored.Results: Kaplan-Meier analysis showed that primary patency was 88.2% (95% confidence interval [CI], 84.5%-92.1%) at 1 year and 80.8% (95% CI, 76.1%-85.8%) at 2 years. The CD-TLR-free rate was 96.5% and 94.8% at 1 and 2 years, respectively. The characteristics associated with loss of patency were restenotic lesion with and without stent implantation (adjusted hazard ratio, 1.96 and 2.40; P = .047 and .041, respectively), chronic total occlusion (adjusted hazard ratio, 1.88; P = .022), and popliteal involvement (adjusted hazard ratio, 2.60; P = .002).Conclusions: The implantation of IWS after sufficient predilation for calcified femoropopliteal atherosclerotic disease demonstrated clinically acceptable primary patency.