Neointimal coverage of sirolimus-eluting stents 6 months and 12 months after implantation: evaluation by optical coherence tomography

作者：Yao Zhu hua; Matsubara Tetsuo; Inada Tsuyoshi; Suzuki Yasuyoshi; Suzuki Takahiko^*

来源：Chinese Medical Journal, 2008, 121(6): 503-507.

DOI：10.1097/00029330-200803020-00005

• optical coherence tomography
• sirolimus-eluting stents
• neointima
• intravascular ultrasound

Background Optical coherence tomography (OCT) is a new imaging modality with resolution of approximately 10 mu m and can be employed to visualize intracoronary characteristics. Sirolimus-eluting stents (SES) are susceptible to late thrombosis due to delayed re-endothelialization over the stent struts, which may result in acute myocardial infarction or death. This study was designed to evaluate the re-endothelialization and neointimal coverage of SES with OCT 6 months and 12 months after implantation.
Methods A total of 36 patients enrolled in the study underwent OCT examination 6 months (17 patients) and 12 months (19 patients) after SES implantation. The strut apposition to the vessel wall and neointimal coverage on SES struts were evaluated by OCT.
Results Forty-six SES and 6561 struts were analyzed. At 6 months, 3041 struts (98.7%) were well-apposed and 39 struts (1.3%) were malapposed. At 12 months, 3434 struts (98.6%) were well-apposed and 47 struts (1.4%) were malapposed. Furthermore, only 4 SES at 6 months (18.2%) and 10 SES at 12 months (41.7%) were fully covered by neointimal growth. The average neointimal thicknesses covering the analyzed struts at 6 months and 12 months were (42+/-28) mu m and (88+/-32) mu m, respectively. There were 1989 struts at 6 months (72.1%) and 1461 struts at 12 months (45.6%) with neointimal thickness <100 mu m.
Conclusions OCT was able to visualize the strut apposition to the vessel wall and neointimal coverage on SES struts. At 6-month and 12-month follow-up examinations most struts were covered with thin neointima, but few of the entire SES showed full coverage. To prevent late-stent thrombosis in the presence of uncovered stent struts, longer dual antiplatelet drugs therapy should be recommended.

• 出版日期2008-3-20