不同设计的两代国产铂铱合金支架对兔颈动脉血管反应的影响

目的　评估不同金属丝直径、不同结构设计的国产铂 铱合金支架对血管反应的影响。方法　将家兔分为三组 ,第一组置入直径 0 .1 3mm单丝缠绕成螺旋形结构的第一代支架 (n =5) ,第二组置入直径 0 .1 75mm单丝缠绕成“之”字形结构的第二代支架 (n =5) ,第三组置入第二代明胶蛋白涂层支架 (n =7)。术后 7d行病理形态分析及扫描电镜观察。结果　所有动物均成功置入支架 ,组织病理学检查显示 :一代和二代支架组各有 1例不完全性血栓形成 ;涂层支架组无血栓形成。支架置入血管无明显炎症反应和异物巨细胞聚集。涂层支架组平均新生内膜厚度与新生内膜面积最小 ,而管腔面积最大 (P均 <0 .0 5)。扫描电镜显示支架表面几乎完全内皮化。结论　支架金属丝直径与结构设计的不同对新生内膜增殖及管腔面积有影响 ;明胶蛋白涂层具有良好的组织相容性。

Different design of platinium-iridium stent influence the vascular response in normal rabbit carotid arteries

Objective　To investigate the influence of stent design and wire diameter on neointimal hyperplasia in normal rabbits carotid artery.Methods　The rabbits were randomly divided into 3 groups:group A were implanted the first generation Pt-Ir stent which were made of 0.13*!mm wire and twisted in a spiral shape (n＝5);group B were implanted the second generation Pt-Ir stent which were made of 0.175*!mm wire and twisted in a zig-zig shape (n=5);group C were implanted the second generation gelatin coated stent (n=7). After 7*!d,we killed the rabbits and inspected results through histopathology and scanning electron microscope.Results　All stents were successfully implanted into rabbits' carotid arteries.Histopathologic examination revealed only one incomplete thrombosis both in the group A and B,and no thrombosis in the group C.There were no inflammation and foreign-body giant cells.Scanning electron microscope showed almost complete endothelialization developed.Mean neointimal thickness and neointimal area of the group C were (56.5±7.0)*!μm and (0.10±0.03)*!mm2,respectively. It had significant difference compared with that of the group A and B［(90.3±11.1)*!μm,(71.3±7.2)*!μm;(0.16±0.01)*!mm2,(0.13±0.09)*!mm2,P＜0.05,respectively］.However,lumen area of the group C was (1.53±0.81)*!mm2 and had significant difference compared with that of the group A and group B ［(0.89±0.38)*!mm2,(1.16±0.45)*!mm2,P＜0.05,respectively］.Conclusion　Different Pt-Ir stent design and wire diameter influence the neointimal hyperplasia and lumen area.The gelatin coated Pt-Ir stent favorably influences the vascular response in a normal rabbit carotid artery.