Study of anastomotic neointimal hyperplasia after vascular prosthesis implantation. Its mechanism and prevention.

吻合口新生内膜肥大（ANH）被认为是最后移植闭塞的一个因素。为了评估和预防ANH，我们在犬体内植入5种小口径移植物，即30、50和90微米纤维长度的聚氨酯（PUG）、膨胀聚四氟乙烯（ePTFE）和自体静脉移植物（AV），并通过光镜和扫描电镜进行病理观察。移植后3个月的累积通畅率为50%，26例移植物中有27%发生ANH。在PUG中ANH明显，在AV中最小，但五组间的增厚率无显著差异。激光吻合术与缝合吻合术相比，两种方法的增厚率无明显差异，但激光吻合术似乎是一种小血管内瘘，内膜愈合良好。建议采用激光吻合术预防ANH。为了评估药物对ANH的预防作用，在移植后给予抗血小板药物。药物治疗组移植物通畅度高于对照组，但增厚率与对照组差异无统计学意义。提示抗血小板药物对ANH的预防效果不明显。

Anastomotic neointimal hypertrophy (ANH) is suggested to be a contributing factor of last graft occlusion. To asess and to prevent ANH,five kind of small caliber grafts, polyurethane (PUG), expanded polytetrafluoroetylene (ePTFE) with 30,50 and 90 micron of fibrile length, and autovein graft (AV) were implanted in dog and pathological observation was performed by light microscopy and SEM.Cmulutative patency rate 3 months after implantation was 50% and ANH was occured in 27% of 26 grafts. ANH was markedly in PUG and was minimal in AV but there was no significant different of thickening rate between the five groups. Compareing anastomotic method of laser with suture, there was no different of thickening rate between the two method but laser anastomosis was seemed to be minilal ANH with good healing of he intima. Laser anastomosis is suggested to prevent ANH.To asess the influence of drug for preventing ANH,antiplatelet drug was administrated to the dog after graft implantation. Graft patency of the drug treatening group was higher than the control group but there was no significant difference of thickening rate between the drug treatening group and the control group. These results suggest that the antiplatelet drug is not effective to prevent ANH.