过大房间隔缺损封堵器对犬术后内皮化的影响

The effect of oversized occluder on endothelialization after percutaneous closure of experimental atrial septal defect in dogs

目的：探讨过大房间隔缺损封堵器对术后封堵器表面内皮化的影响。方法在经胸超声心动图的引导下，在18只实验犬中建立直径为（6.0±0.2）mm的房间隔缺损模型。采用完全随机化方法将实验犬分为正常组及过大组（每组各9只实验犬），正常组置入直径8 mm封堵器，过大组置入直径12 mm封堵器。术后3、6、14个月分别处死实验犬，通过扫描电镜观察各组封堵器表面的内皮化进程。结果4只实验犬在术后1个月左右死亡。正常组术后3个月封堵器表面已基本内皮化，术后6和14个月均为完全内皮化；过大组术后3个月封堵器表面内皮化程度不佳，术后6个月基本内皮化，术后14个月才完全内皮化。结论采用过大封堵器治疗实验犬房间隔缺损，术后6个月封堵器表面尚未完全内皮化。

Objective To observe the effect of oversized occluder on endothelialization post percutaneous closure of experimental atrial septal defect （ ASD） in dogs.Methods ASD was established with the help of transthoracic echocardiography in 18 dogs.ASD size was （ 6.0 ±0.2 ） mm.Dogs were randomly divided into normal size group （ implanted with 8 mm occlude , n =9 ） and oversized group （implanted with 12 mm occluder, n =9）.Dogs were randomly killed at 3, 6 and 14 months after percutaneous closure.The endothelialization process on device surface was observed by scanning electron microscope.Results Four animals died around 1 month post procedure.Microscopic sections from normal group showed nearly complete endothelialization at 3 months after device implantation and complete endothelialization at 6 and 14 months after device implantation.While microscopic sections showed lack of endothelialization at 3 months post implantation , nearly endothelialization at 6 months, and complete endothelialization at 14 months after device implantation in oversized group.Conclusion Incomplete endothelialization of occluder surface is observed at 6 months after implantation of an oversized ASD occluder device in this model.