Shiroma H, Kusaba A
Second Department of Surgery, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan.
Cardiovasc Surg. 1996 Jun;4(3):393-8. doi: 10.1016/0967-2109(95)00081-x.
The features of intimal hyperplasia at the distal end-to-side anastomosis of arterially implanted autovein bypass grafts in dogs were examined using light and transmission electron microscopy. The bypass grafting was done under conditions of reduced blood flow with an abnormal flow wave and high peripheral resistance. Anastomotic intimal hyperplasia was evident 14 to 31 days after implantation, then gradually increased, particularly at the toe portion of the anastomosis. From 6 to 12 months after implantation, the intimal hyperplasia was excessively increased and severe luminal stenosis had developed. The hyperplastic neointima consisted of two layers; a laminated superficial layer and a randomly arranged deeper layer. The superficial layer had three to four layers of smooth muscle cells, while the deeper layer was mostly fibrocollagenous tissues. Thus, the intimal hyperplasia at the distal end-to-side anastomosis of the arterially implanted autovein graft developed as a result of infiltration of fibroblast-like cells, presumably tissue-synthesizing mesenchymal cells. The neointima at the distal anastomosis, under conditions of reduced blood flow with high peripheral resistance, remained in an active phase of intimal hyperplasia even 12 months after bypass grafting.
利用光学显微镜和透射电子显微镜，对犬动脉植入自体静脉旁路移植远端端侧吻合处内膜增生的特征进行了研究。旁路移植术是在血流减少、血流波异常和外周阻力高的条件下进行的。吻合口内膜增生在植入后14至31天明显，然后逐渐增加，特别是在吻合口的趾部。植入后6至12个月，内膜增生过度增加，出现严重的管腔狭窄。增生的新生内膜由两层组成；一层为分层的表层，另一层为随机排列的深层。表层有三到四层平滑肌细胞，而深层主要是纤维胶原组织。因此，动脉植入自体静脉移植物远端端侧吻合处的内膜增生是由成纤维细胞样细胞（可能是组织合成间充质细胞）浸润所致。在高外周阻力导致血流减少的情况下，远端吻合处的新生内膜在旁路移植术后12个月仍处于内膜增生的活跃期。
