紫杉醇洗脱支架在小猪糖尿病模型外周动脉中抑制再狭窄的实验研究

摘要

目的 研究紫杉醇洗脱支架(PES)在小猪糖尿病模型外周动脉中抑制再狭窄的效果.方法小猪10头,通过静脉注射链脲菌素(STZ)成功建立糖尿病模型.小猪血糖升高并且稳定2周后,颈部切开,经右侧颈总动脉造影明确双下肢动脉情况.选择没有明显分支的髂动脉作为靶血管,测量其直径,按照支架与血管直径1.1～1.2:1比例随机植入PES或裸金属支架(BMS).术后3个月行CT血管造影(CTA),6个月行数字减影血管造影(DSA),测量支架处直径,处死猪取支架段行苏木素伊红(HE)染色及扫描电镜检查,观察其内膜厚度及内皮化情况.结果10头小猪注射STZ后1头死亡,其余血糖均升高,且稳定.2周后行介入操作,其中PES组5头,BMS组4头.术后第二天PES组小猪死亡1头,余小猪随访期内无死亡.3个月CTA及6个月DSA显示两组均无支架内狭窄;大体标本显示,PES组2枚支架部分裸露,2枚内皮化良好;BMS组4枚支架内皮化良好;光镜显示两组支架内膜厚度相仿;扫描电镜显示PES组4枚均存在内皮化不全,BMS组内皮化完全.结论在小猪糖尿病模型的外周动脉中,6个月随访显示PES在抑制内膜增生方面没有优于BMS,且存在内皮化不全,有待更长时间的随访.%Objective To evaluate the effect of paclitaxel-eluting stent (PES) inhibits restenosis in peripheral arteries in a swine model of diabetes. Methods Diabetes model were established successfully in 10 pigs through intravenously streptozocin (STZ). A digital subtraction angiography (DSA) of lower extremity arteries was performed via right common carotid artery approach for each pig under general anesthesia as the blood glucose elevated and maintained stable for two weeks. Iliac artery without visible branch was selected as the target vessel. Diameter of the target vessel was calculated and then a PES or bare metal stent (BMS) with a ratio of 1.1-1.2:1 (stent:vessel) was implanted randomly. All pigs were fed with 100 mg of aspirin and 50 mg of clopidogrel hydrogensulfate after procedure. Computed tomography angiography (CTA) and DSA were performed to elucidate the intra-stent diameter at three- and six-month postoperatively, respectively. Afterwards, all pigs were sacrificed and stents were extracted for H&E staining and scanning electron microscopy examination. Results All except one pigs survived with a hyperglycemia after STZ injection. Nine stents were implanted including PES in five and BMS in four. After the procedure, one pig in PES group died in the second day after operation while the others stayed alive during the study duration. No intra-stent stenosis was observed in either groups. There was no significant difference in intima thickness between PES and BMS groups. However, complete endothelialization were found in all cases of BMS group while PES group showed insufficient endothelialization in stents. Conclusion PES is not superior to BMS in inhibiting neointimal hyperplasia in a swine model of diabetes during six months follow-up. Nonetheless, incomplete endothelialization is related to the utilization of PES. Thus, the efficacy of PES requires further study via a longer term follow-up.