Masuda H, Ogata T, Kikuchi K, Tanaka S
Second Department of Surgery, National Defense Medical College, Saitama, Japan.
Ann Thorac Surg. 1989 Sep;48(3):376-80. doi: 10.1016/s0003-4975(10)62860-3.
We previously reported that the expanded polytetrafluoroethylene (ePTFE) graft for superior vena cava (SVC) substitution presents the problems of flexion and kinking when the graft is long. We therefore replaced the SVC of dogs with two types of prosthetic substitutes, ePTFE (Gore-Tex) and spiral-supported ePTFE (Im/praflex), and evaluated the long-term patency of the prosthetic substitutes. Total replacement of the SVC was performed in 9 adult mongrel dogs. The substitutes were ePTFE and spiral-supported ePTFE in 5 and 4 dogs, respectively. The animals were killed about 3 years after replacement of the SVC, and the harvested specimens were histologically examined by light microscopy and scanning electron microscopy. Evaluation of ePTFE revealed late occlusion in 1 of 5 dogs. The spiral-supported ePTFE showed patency in all dogs. In the group with ePTFE grafts, light microscopic examination revealed abnormalities of endothelial cells, granulation, and necrosis. There was no hyperplasia of the subendothelial connective tissue near the center. In the animals with spiral-supported ePTFE grafts, the subendothelial connective tissue showed favorable growth even in the center of the reconstructed site. There was no granulation in the spiral-supported ePTFE group. Scanning electron microscopic examination in the ePTFE group showed that endothelial cells were spindle-shaped and had an irregular surface. The spiral-supported ePTFE group showed an almost regular form of endothelial cells and no abnormalities except for the slightly spindled shape in the center. Therefore, we recommend that spiral-supported ePTFE should be used as an SVC substitute in clinical situations.
我们之前报道过，用于上腔静脉（SVC）置换的膨体聚四氟乙烯（ePTFE）移植物在移植物较长时会出现弯曲和扭结问题。因此，我们用两种人工替代物，即ePTFE（戈尔特斯）和螺旋支撑ePTFE（Im/praflex）置换了犬的SVC，并评估了人工替代物的长期通畅性。对9只成年杂种犬进行了SVC的全置换。分别有5只和4只犬使用了ePTFE和螺旋支撑ePTFE作为替代物。在置换SVC约3年后处死动物，对收获的标本进行光学显微镜和扫描电子显微镜组织学检查。对ePTFE的评估显示，5只犬中有1只出现晚期闭塞。螺旋支撑ePTFE在所有犬中均显示通畅。在使用ePTFE移植物的组中，光学显微镜检查显示内皮细胞异常、肉芽组织形成和坏死。中心附近的内皮下结缔组织没有增生。在使用螺旋支撑ePTFE移植物的动物中，即使在重建部位的中心，内皮下结缔组织也显示出良好的生长。螺旋支撑ePTFE组没有肉芽组织形成。ePTFE组的扫描电子显微镜检查显示内皮细胞呈纺锤形，表面不规则。螺旋支撑ePTFE组显示内皮细胞形态几乎正常，除中心部位稍呈纺锤形外无异常。因此，我们建议在临床情况下应使用螺旋支撑ePTFE作为SVC替代物。
