Angioscopic differences in neointimal coverage and in persistence of thrombus between sirolimus-eluting stents and bare metal stents after a 6-month implantation

Abstract

Aims: The neointimal coverage and intracoronary thrombi within stented segments at 6 months after implantation between sirolimus-eluting stents (SESs) and bare metal stents (BMSs) were compared by direct visualization using angioscopy. Methods and results: Forty-six patients (36 stable angina and 10 acute coronary syndrome) were treated with 33 SESs and 33 BMSs. Immediately after and 6 months after stenting, each of the stented segments, edge body, and overlapping segment were observed by angioscopy and the grade of neointimal coverage over the stents was classified as 0: absent neointima, 1: visible struts through thin neointima, or 2: invisible struts. The existence of thrombi was also evaluated. The average grade of the neointimal coverage at 6 months follow-up was lower in the SES than that in the BMS (edge: 1.4 ± 0.7 vs. 1.9 ± 0.2, body: 1.0 ± 0.5 vs. 1.8 ± 0.5, overlapping segment: 0.6 ± 0.7 vs. 1.8 ± 0.5; P < 0.0001, P < 0.0001, P = 0.0069, respectively). The frequency of persistence of thrombus was significantly higher in the SESs than that in the BMSs (86 vs. 29%, respectively; P = 0.031). Conclusion: The present study suggested a delayed neointimal stent coverage and slower thrombus disappearance process in the SESs in comparison to the BMSs. © The European Society of Cardiology 2006. All rights reserved.