光学相干断层显像评价药物洗脱支架置入后内膜增殖和血栓形成

Evaluation of neointimal coverage and thrombosis at 3 months and 2 years post sirolimus-eluting stent implantation by optical coherence tomography

目的应用光学干涉断层显像（OCT）技术评价雷帕霉素洗脱支架（SES）置入后3个月和2年后内膜增殖和支架内血栓形成情况。方法对3个月组进行SES置入后3个月的OCT随访观察，对2年组进行SES置入后2年的随访观察。测量每一个支架支撑杆表面的新生内膜厚度，并评估无内膜覆盖支架支撑杆及支架内血栓形成情况。结果2年组的内膜厚度显著大于3个月组[（71±93）μm比（29±41）μm，P〈0．01]，而2年组中的无内膜覆盖支架支撑杆的比例明显低于3个月组（5％比15％，P〈0．01）。2年组与3个月组无内膜覆盖支撑杆患者的比例差异无统计学意义（81％比95％，P〉0．05）。两组中均有14％的患者出现无临床症状的支架内血栓形成。结论SES置入后3个月到2年新生内膜的增生在不断进展，无内膜覆盖支撑杆数明显减少。但是直到支架置入后2年，多数患者体内仍然存在部分无内膜覆盖的支架支撑杆。

Objective To evaluate the short- and long-term prevalence of persistent uncovered struts and in-stent thrombus after sirolimus-eluting stent （SES） implantation by optical coherence tomography （OCT）. Methods OCT was performed for 31 SES in 21 patients at 3 months and for 30 SES in 21 patients at 2 years post SES implantation. Thickness of new intima inside each strut was measured and thickness equal to 0 μm was defined as an uncovered strut. Existence of in-stent thrombus was also evaluated. Results A total of 4545 struts and 3707 struts were evaluated at 3 months and at 2 years post SES implantation, respectively. New intima at 2 years was significantly thicker than that at 3 months [ （71 ±93）μm vs. （29 ±41 ） μm, P 〈 0.01 ]. Percent of uncovered struts at 2 years was significantly lower than that at 3 months （5 % vs. 15 % , P 〈 0. 01 ）. Prevalence of uncovered struts was similar at 2 years and at 3 months （ 81% vs. 95 % , P 〉0. 05）. Subclinical thrombus was recognized in 14% patients at 3 months and 2 years post SES implantation. Conclusions Neointimal coverage inside the SES is a continuous process and the number of uncovered struts decreased from 3 months to 2 years after SES implantation. Few uncovered struts could still be visualized in the majority of patients at 2 years post SES implantation.