Serial Comparison of 1-Month and 12-Month Vessel Responses between Polymer-Free Biolimus A9-Coated Stent and Durable-Polymer Everolimus-Eluting Stent

Background: A polymer-free biolimus A9-coated stent (PF-BCS) may achieve better arterial healing than a durable polymer drug -eluting stent owing to its polymer-free feature.Methods and Results: This multicenter, prospective, observational study enrolled 105 patients (132 lesions) who underwent PF-BCS (51 patients, 71 lesions) or durable polymer everolimus-eluting stent (DP-EES, 54 patients, 61 lesions) implantation. Serial coronary angioscopy (CAS) and optical coherence tomography (OCT) examinations were performed at 1 and 12 months, and the serial vessel responses were compared between PF-BCS and DP-EES. The primary outcome measure was the incidence of sub -clinical intrastent thrombus on CAS. The secondary outcome measures were: adequate strut coverage (>= 40 mu m) on OCT and maxi-mum yellow color grade on CAS. The incidence of thrombus was high at 1 month (100% vs. 93%, P=0.091), but decreased at 12 months (18% vs. 25%, P=0.56), without a significant difference between PF-BCS and DP-EES. The adequate strut coverage rate was significantly higher (84 +/- 14% vs. 69 +/- 22%, P<0.001) and yellow color was significantly less intense (P=0.012) at 12 months in PF-BCS than in DP-EES; however, they were not significantly different at 1 month (adequate strut coverage: 47 +/- 21% vs. 50 +/- 17%, P=0.40; yellow color: P=0.99).Conclusions: Although the thrombogenicity of PF-BCS was similar to that of DP-EES, the adequate coverage and plaque stabiliza-tion rates of PF-BCS were superior to those of DP-EES at 12 months.