颅内动脉瘤用纳米电纺覆膜支架初步实验研究

Implantation of nano electro- spinning covered stent for the treatment of intracranial aneurysm :preliminary experimental study

目的动物实验研究评价新型颅内动脉瘤用纳米电纺覆膜支架的力学性能和生物相容性。方法 10只健康成年比格犬中共植入20枚纳米电纺覆膜支架,其中10枚0.10 mm丝径支架植入左侧锁骨下动脉(A组),10枚0.15 mm丝径支架植入右侧锁骨下动脉(B组)。支架植入术后即刻和术后2、4、6周分别作血管造影随访。支架段血管作组织学病理检查,评价支架内皮化和内膜增生情况。结果 A组支架植入后即刻造影示7枚支架内漏,随访期间2枚支架内漏消失,5枚仍残留内漏;B组支架植入后即刻造影示1枚支架内漏,随访期间内漏消失,3枚支架发生轻度狭窄(狭窄程度<50%)。组织病理学检查显示,B组术后2周血管壁呈慢性炎性反应,术后4周支架内表面部分血管内皮化,术后6周支架内表面基本实现血管内皮化。结论本实验研究初步证明纳米电纺覆膜支架治疗颅内动脉瘤的有效性和可行性,具有重要临床应用价值。但该支架尚处于初始研究阶段,有待进一步远期观察和研究。

Objective To evaluate the mechanical properties and biocompatibility of nano electrospinning （NES） covered stent, regarded as a new type of covered stent, in the treatment of intracranial aneurysm by using animal experiment. Methods A total of 20 NES covered stents were implanted into 10 healthy beagle dogs; implantation of NES covered stent of 0.10 mm diameter wire in the left subclavian artery was performed in 10 dogs （group A）, and implantation of NES covered stent of 0.15 mm diameter wire in the right subclavian artery was performed in the same 10 dogs （group B）. Follow-up angiography examinations were respectively performed immediately after the implantation as well as at 2, 4 and 6 weeks after the implantation. The blood vessels of stenting segment were histopathologically examined, and the endothelialization status of the stent and the intimal hyperplasia were evaluated. Results In group A, angiography preformed imnmdiately after the stent was implanted revealed that endoleak was seen in seven stents. During follow-up period, the endoleak disappeared in two stents, and the endoleak remained in the other five stents. In group B, angiography preformed immediately after the stent iamplantation showed that endoleak was detected in one stent, which disappeared in follow-up period. Mild stenosis （stenosis degree〈50% ） was observed in three stents. Histopathological examination of the blood vessel specimens of group B revealed that at 2 weeks after the treatment the vessel wall showed a chronic inflammatory reaction, at 4 weeks after the treatment partialendothelializalion appeared in the inner surface of the stent, and at 6 weeks after the treatment the inner surface of the stent became basically complete endothelialization. Conclusion The results of this study provide preliminary proof for the effectiveness and feasibility of NES covered stent for the treatment of intraeranial aneurysms, although its long-term results need to be further observed and studied as this stent is still in the initial stage of study.