2201Comparative efficacy and safety of novel biodegradable polymer sirolimus-eluting stents versus permanent polymer everolimus-eluting stents at 5-year follow-up

Abstract

Aims: Biodegradable polymers aim to promote arterial healing by reducing the risk of polymer-induced inflammation seen with durable polymer drug-eluting stents. The aim of this study was to compare 5-year clinical outcomes in patients treated with a novel biodegradable polymer sirolimus-eluting stent versus a durable polymer everolimus-eluting stent. Methods: 5-year clinical outcomes in patients treated with a novel biodegradable polymer sirolimus-eluting stent enrolled in a prospective registry were compared with patients treated with a durable polymer everolimus-eluting stent enrolled in the ISAR-TEST 4 randomised trial. Patients with stable coronary artery disease undergoing PCI of De novo lesions were eligible for inclusion. Exclusion criteria included target lesion located in the left main stem and cardiogenic shock. The sirolimus-eluting stent consists of a stainless steel backbone coated with 2.0 μg/mm2 sirolimus eluted by a biodegradable linear polyester polymer with defined polylactide content, typically degraded within 2 months of implantation. The everolimus-eluting stent consists of a cobalt-chromium backbone coated with 100 μg/cm2 everolimus and 2 durable polymers: an acrylic polymer and a fluoro polymer. The primary safety endpoint was the combined incidence of death and myocardial infarction and the primary efficacy endpoint was the incidence of targetlesion revascularisation at 5 years. Stent thrombosis was a secondary endpoint. Multivariate analysis was performed to adjust for baseline differences between treatment groups. Results: 866 patients were treated with the sirolimus-eluting stent (n=214) or the everolimus-eluting stent (n=652). Compared with patients in the sirolimus-eluting stent group, patients in the everolimus-eluting stent group had longer lesion length, as well as smaller minimal lumen diameter and greater % diameter stenosis before and after PCI. At 5-year follow-up, the primary safety endpoint occurred in 39 (18.9%) vs. 118 (18.8%) patients in the sirolimus- vs. everolimus-eluting stent groups, respectively (Padjusted=0.81). The primary efficacy endpoint occurred in 28 (14.2%) vs. 85 (14.1%) patients, respectively (Padjusted=0.67). Stent thrombosis occurred in 0 (0%) patients treated with the sirolimus-eluting stent versus 4 (0.6%) treated with the everolimus-eluting stent (Padjusted<0.001). Conclusions: At 5-year follow-up, rates of stent thrombosis were higher in patients treated with a durable polymer everolimus-eluting stent versus a biodegradable polymer sirolimus-eluting stent, with comparable rates of death, myocardial infarction and target vessel revascularisation between treatment groups.