Evaluation of neointimal coverage and apposition with various drug-eluting stents over 12 months after implantation by optical coherence tomography

BackgroundOptical coherence tomography (OCT) is an imaging technology with high resolution which provides new opportunities for evaluating the vascular healing reaction after stent implantation. We used OCT to compare neointimal coverage and stent strut apposition with different types of drug-eluting stent (DES) at more than 12 months follow-up.MethodsFifty five patients who accepted 72 DESs (19 sirolimus-eluting stents [SES, Cypher Select], 27 paclitaxel-eluting stents [PES, Taxus Liberte], 26 zotarolimus-eluting stents [ZES, Endeavor]) were enrolled in our study. OCT was performed at 12–18 months after stent implantation. The neointimal hyperplasia (NIH) thickness and stent strut apposition at 1-mm interval and the presence of thrombus in each stent were observed.ResultsThe average NIH thickness (0.1806 ± 0.1726 mm in SES vs. 0.2558 ± 0.2187 mm in PES vs. 0.2983 ± 0.2567 mm in ZES, p < 0.001) and percentage of NIH area (17.21 ± 14.05% in SES vs. 23.09 ± 14.53% in PES vs. 28.73 ± 20.47% in ZES, p = 0.002) were significantly greater in ZES than in other DESs. The prevalence of uncovered struts (8.96% in SES vs. 6.19% in PES vs. 2.98% in ZES, p < 0.01) and malapposed struts (6.36% in SES vs. 2.32% in PES vs. 1.69% in ZES, p < 0.01) was significantly lower in ZES than in other DESs. Thrombus was less frequently observed in ZES than in other DESs (SES 1.70% vs. PES 0.83% vs. ZES 0.17%, p < 0.01).ConclusionsCompared with SES and PES, ZES showed lower prevalence of uncovered struts and malapposed struts at more than 12 months follow-up.