Detailed Intravascular Ultrasound Analysis of Zotarolimus-Eluting Phosphorylcholine-Coated Cobalt-Chromium Alloy Stent in de Novo Coronary Lesions (Results from the ENDEAVOR II Trial)

Zotarolimus-eluting phosphorylcholine-coated cobalt-chromium alloy Driver stents (ZES) demonstrated significant reductions in target lesion revascularization rate with few apparent adverse events compared with bare metal stents (BMS; uncoated Driver stents) in a prospective, multicenter, double-blind, randomized controlled trial in de novo coronary lesions. The aim of this study was to examine detailed vascular responses to ZES compared with BMS using serial intravascular ultrasound analysis. A total of 343 patients (ZES n = 178, BMS n = 165) were enrolled in this formal, prespecified intravascular ultrasound substudy of the Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE Zotarolimus-Eluting Driver Coronary Stent in de Novo Native Coronary Artery Lesions (ENDEAVOR II), a prospective, multicenter, double-blind, randomized controlled trial to compare ZES and BMS in de novo native coronary artery lesions. Quantitative and qualitative intravascular ultrasound analyses were performed postprocedurally and at 8-month follow-up in stented and reference segments. ZES showed significantly less neointima, with a larger lumen than BMS at 8 months (percentage neointimal volume 17.6 ± 10.1% vs 29.4 ± 17.2%, p <0.0001; maximum percentage neointimal area 32.9 ± 13.0% vs 47.6 ± 18.6%, p <0.0001; minimum luminal area 4.9 ± 1.6 vs 4.0 ± 1.7 mm2, p <0.0001) and no unfavorable edge effect. In the 18-mm single stents, ZES showed evenly inhibited neointima compared with BMS. Neither persistent stent-edge dissection nor late-acquired incomplete stent apposition was observed in either group. In conclusion, ZES showed evenly inhibited neointima with no apparent adverse vascular response in stented and reference segments at 8 months compared with BMS.