Short-term healing response after implantation of the thin-strut, fast-releasing sirolimus-eluting biodegradable polymer-coated Alex Plus stent: optical coherence tomography study

摘要

Introduction Technological improvements in drug-eluting stents (DES) have led to drastic reductions in restenosis and acute stent thrombosis rates. However, chronic inflammation and late and very late stent thrombosis, particularly with the first generation durable polymer DES (DP-DES), prompted the development of new DES platforms that use biodegradable polymers. The advantage of biodegradable polymers relies on the resorbable property of these polymers, reducing in this way the polymer-induced chronic inflammation and related clinical events such as restenosis and stent thrombosis. Notwithstanding , despite the theoretical advantages of bioabsorbable polymer DES (BP-DES), there are limited data focused on its very early vascular healing process. Aim Therefore, we aimed to assess the 1-month vascular healing response following implantation of the bioabsorbable polymer-coated sirolimus-eluting stent Alex Plus (BP-SES, Alex Plus, Balton, Warsaw, Poland). Material and methods Study population In this prospective, single-centre study, patients aged 18 years and older undergoing percutaneous coronary intervention (PCI) for treatment of de novo coronary lesions with implantation of a bioresorbable polymer sirolimus-eluting stent (BP-SES), Alex Plus, for any clinical indication were enrolled. Major exclusive criteria were renal failure (glomerular filtration rate less than 45 ml/min/1.73 msup2/sup), allergy to contrast media or any of the stent components, hemodynamic compromise at presentation, pregnancy as well as participation in other clinical trials. Stent system description Alex Plus is composed of a laser-cut cobalt-chromium alloy stent platform with open-cell geometry and 71 μm struts with a fully biodegradable circumferential coating (copolymer of poly-L-lactic and glycolic acid) and the anti-proliferative drug sirolimus. Experimental studies showed 95% release of the drug after 28 days and practically full polymer biodegradation after 8 weeks following Alex Plus implantation [1]. Optical coherence tomography Optimal coherence tomography (OCT) using iLumien OPTIS Medical system (Abbott Vascular, Santa Clara, CA, USA) imaging was performed before and after stent implantation as well as at 1-month follow-up. The OCT registration included the entire stented segment as well as 5 mm proximally and distally to the stent. The OCT image was acquired using automated pullback...