A Study of Anastomotic Neointimal Hyperplasia After Graft Inplantation.

尽管血管假体得到了改善，但小血管置入术后的长期通畅率仍未达到。吻合口新生内膜增生（ANH）被认为是移植物植入后闭塞的一个因素，血管假体与宿主动脉的力学特性差异、移植物流动异常、手术引起的内膜损伤、吻合口表面血小板聚集、缝合材料和方法等是引起ANH的因素。在本研究中，我们研究了(1)血管移植物与宿主动脉力学性能的差异。(2)犬小口径（直径3mm）移植物植入术及植入术后吻合部位的长期观察。(3)移植物与ANH血栓形成的比较。研究结果如下：(1)研制了一种新型超声位移仪，测量了动脉移植物的顺应性。将人血管的顺应性与移植物的顺应性进行比较，发现移植物与动脉的顺应性明显不匹配。(2)犬用直径3mm的不同顺应性的移植物（ePTFE、分段聚氨酯移植物）置换颈动脉，进行长期观察。高顺应性移植的通畅率为50%/1年，低顺应性移植和高顺应性移植均发生ANH。血管假体与宿主动脉的顺应性不匹配被认为是导致ANH的因素之一，但似乎不是主要因素。(3)评价接枝表面血小板聚集与ANH的关系。^<111>的患者在移植早期和晚期进行血小板显像。植入后早期高血小板聚集组与低血小板聚集组的通畅率差异有统计学意义，但两组间ANH的发生无统计学差异。少

Despite improvement of the vascular prostheses, the long term patency rate remains unfulfilled after small caliver graft implantation. Anastomotic neointimal hyperplasia (ANH) is known as a contributing factor of graft occlusion after implantation and the difference of mechanical properties between a vascular prosthesis and its host arteries, abnormal graft flow, intimal trauma due to surgical procedure, platelet aggregation in a surface of anastomotic site, suture material and method are suggested the factors of ANH.In this study, we investigated (1) the difference of mechanical properties between vascular grafts and host arteries. (2) small caliber(3mm in diameter) graft implantation in dogs and long term observation of the anastomotic site after implantation. (3) comparison of thrombogenecity of grafts and ANH. The results are as follows ;(1) A new type ultrasonic displacement meter was developed and compliance of arterial grafts ware measured. In comparison of compliance of human a … More rteries to that of grafts, a mismatch in compliance between grafts and arteries was obviously demonstrated.(2) In dogs, carotid artery was replaced with different compliance of graft (ePTFE, segmented polyurethane graft) 3mm in diameter and long term observation was performed. The rate of patency was good in high compliance graft (50%/1 year) but ANH was occurred both in low compliance graft and high compliant graft. Compliance mismatch between vascular prosthesis and host arteries is suggested to be one of the factor contributing ANH, but it seems to be not a main factor.(3) To evaluate relationship between platelet aggregation in a surface of graft and ANH. In^<111> platelet scintigraphy was performed in the early and late stage of graft implantation. There was significant difference of the patency rate between high platelet aggregation group and low plate let aggregation group in the early stage after implantation but there was no difference of occurrence of ANH between the two groups. Less