Vascular Healing After Biodegradable Polymer Sirolimus-Eluting Versus Durable Polymer Everolimus-Eluting Stents in Chronic Total Occlusions

Abstract

Background: Biodegradable polymer stents may reduce the risk of neoatherosclerosis and stent thrombosis. Limited data is available for biodegradable polymer sirolimus-eluting stent (BP-SES) and durable polymer drug-eluting stents (DP-EES) in chronic total occlusions (CTO). Aim: This study was to evaluate healing patterns of BP-SES versus DP-EES in CTO at 3 and 13 months based on optical coherence tomography (OCT). Methods: The TARGET-CTO study is a prospective, multicenter, randomized noninferiority controlled trial for BP-SES compared to DP-EES in CTO. In the current predefined subanalysis, 44 consecutive patients underwent OCT follow-up at 3 and 13 months. The primary endpoint was mean neo-intimal thickness at 3 months. Results: At 3 months, mean neo-intimal thickness was 47.6 ± 15.7 µm in BP-SES and 62.5 ± 37.3 µm in DP-EES (p = 0.384), meeting the noninferiority for BP-SES (pnoninferiority < 0.001). Mean neo-intimal thickness at 13 months was 76.4 ± 34.1 µm in BP-SES and 106.6 ± 54.9 µm in DP-EES (p = 0.086). No significant differences in strut coverage were observed at 3 or 13 months. At 13 months significantly higher percentages of frames with layered neo-intima and neoatherosclerosis were observed in DP-EES compared to BP-SES (p = 0.015 and p = 0.021, respectively). Conclusions: BP-SES was noninferior to DP-EES in terms of neo-intimal thickness at 3 months and healing responses at 3-month follow-up were comparable. At 13 months, less advanced neoatherosclerosis patterns were observed in BP-SES as compared to DP-EES.