Feasibility Assessment of Interposition Vessel Graft Substitutes in Dog Models for Later Clinical Application to Middle Hepatic Vein Reconstruction during Living Donor Liver Transplantation

ABSTRACT

PURPOSE: Most of grafts used as interposition conduits for middle hepatic vein (MHV) in living donor liver transplantation (LDLT) have been allografts and autografts. Recently, polytetrafluoroethylene (PTFE) and bovine pericardium patch have also been used. Thus, we performed large-animal lab tests to assess the feasibility of interposition vessel graft substitutes for MHV. METHODS: The inferior vena cava was replaced in 9 dogs with allograft (3), PTFE (3), and bovine pericardium patch (3). After 28 days, patency rate, outer and inner diameter, intimal thickness, histology, and immunohistochemistry were evaluated according to interposition grafts. RESULTS: The allograft and PTFE groups were all patent at post-operative week 4, but the bovine group was not patent in all dogs. Outer diameter of anastomotic site at 4 weeks was 8.41+/-0.37, 10.83+/-0.51, and 7.41+/-0.86 mm in allograft, PTFE, and bovine group, respectively. Inner diameter of interposition graft at 4 weeks was 7.90+/-0.23, 6.33+/-0.68, and 0 mm in allograft, PTFE, and bovine groups, respectively. Intimal thickness was 48.0+/-8.6, 113.8+/-45.3, and 218.3+/-59.9microm in allograft, PTFE, and bovine groups, respectively. In histologic findings, inflammation was most severe in the bovine group. Intima of anastomotic site in the bovine group was thickest in all groups. Proliferation of smooth muscle cells was most severe in anti-alpha-actin antibody test in bovine group. CONCLUSION: Our data implicate that the use of allografts and PTFE grafts is more feasible than bovine pericardium for MHV reconstruction in LDLT.