Yee D C, Williams S K, Salzmann D L, Pond G D, Patula V, Berman S S, Roach D J
Department of Radiology, University of Arizona Health Science Center, Tucson 85721-0101, USA.
J Vasc Interv Radiol. 1998 Jul-Aug;9(4):609-17. doi: 10.1016/s1051-0443(98)70331-8.
To evaluate the healing characteristics of stents versus endovascular grafts in the porcine iliac artery.
A total of 20 iliac arteries in 10 domestic swine were used to evaluate the healing characteristics of stents versus endovascular grafts. Each animal received one stent and one endovascular graft in opposite iliac arteries. The endovascular grafts were constructed with use of 6 cm of expanded polytetrafluoroethylene (ePTFE) (3 mm inner diameter, 30 microm internodal distance) and Palmaz stents (P204 or P188) secured at each end of the graft. A solitary Palmaz stent (P308 or P294) was used on the opposite side. The devices were explanted at 1, 5, and 12 weeks.
One of three endovascular grafts and two of three stents were patent at 1 week. Two of three endovascular grafts and all three stents were patent at 5 weeks. All three endovascular grafts and stents were patent at 12 weeks. Gross examination, histologic, and scanning electron microscopy demonstrated differences in the healing response of the two devices. A marked abluminal inflammatory response to the graft material was observed. This resulted in neovascularization of the tissue along the abluminal surface of the graft. In addition, marked neointimal thickening at the unsupported section of the endovascular graft resulted in significant luminal narrowing.
The porcine model may be used for evaluating the healing characteristics of endovascular grafts. Intravascular placement of ePTFE prosthetic graft material dramatically alters the healing of this type of graft material. The graft material did not prevent the formation of a progressively thickening neointima.
评估猪髂动脉中支架与血管内移植物的愈合特性。
使用10头家猪的20条髂动脉来评估支架与血管内移植物的愈合特性。每只动物在对侧髂动脉中分别植入一个支架和一个血管内移植物。血管内移植物采用6厘米的膨体聚四氟乙烯（ePTFE）构建（内径3毫米，节距30微米），两端固定有帕尔马兹支架（P204或P188）。对侧使用单个帕尔马兹支架（P308或P294）。在1周、5周和12周时取出装置。
在1周时，三个血管内移植物中有一个通畅，三个支架中有两个通畅。在5周时，三个血管内移植物中有两个通畅，所有三个支架均通畅。在12周时，所有三个血管内移植物和支架均通畅。大体检查、组织学和扫描电子显微镜显示两种装置的愈合反应存在差异。观察到对移植物材料有明显的管腔外炎症反应。这导致沿移植物管腔外表面的组织新生血管形成。此外，血管内移植物无支撑部分明显的新生内膜增厚导致管腔显著狭窄。
猪模型可用于评估血管内移植物的愈合特性。ePTFE人工移植物材料的血管内放置显著改变了这种类型移植物材料的愈合。移植物材料未能阻止逐渐增厚的新生内膜的形成。
