Safety and Efficacy of New Sirolimus-Eluting Stent Models in A Preclinical Study

Introduction and objectives: Initial preclinical studies are required during the process of improving polymers, platforms, and drug-eluting systems for new coronary stent designs. Our objective was to analyze the efficacy and safety of new drug-eluting stent models compared with a conventional stent and commercialized drug-eluting stents in an experimental model with healthy porcine coronary arteries.Methods: Sixty stents (conventional stent, new sirolimus-eluting stents: drug-eluting stents 1, 2 and 3; Cypher (R) and Xience (R)) were randomly placed in the coronary arteries of 20 Large White domestic pigs. Angiographic and histomorphometric studies were done 28 days later.Results: The stents were implanted at a stent/artery ratio of 1.34 +/- 0.15, with no significant differences between groups. The new stents showed less late loss and angiographic restenosis than conventional stents (P = .006 and P < .001, respectively). Histologically, restenosis and neointimal area were lower with all the new platforms than with the conventional stents (P < .001 for each variable), and no differences were found vs the drug-eluting stents on the market. Safety data showed that endothelialization was lower with drug-eluting stents than with conventional stents, except for drug-eluting stent 3 (P = .084). Likewise, inflammation was lower with drug-eluting stent 3 than with other stents.Conclusions: The new drug-eluting stent platforms studied are associated with less restenosis than conventional stents and showed no significant differences in safety or efficacy vs commercialized drug-eluting stents. (C) 2015 Sociedad Espanola de Cardiologia. Published by Elsevier Espana, S.L.U. All rights reserved.