Significance of Portosystemic Shunt on Graft Survival in Liver Transplantation: A Rat Model

Aims: Distal splenorenal shunt effectively controls bleeding from esophageal and gastric varices but has a different effect on liver transplantation. This study sought to develop an animal model in rats to mimic the recipient with a portosystemic shunt and to investigate its hemodynamic consequences on liver transplantation. Methods: We prepared 5 groups of allogeneic or syngeneic rat liver transplantation models with versus without portosystemic shunt, to investigate its effects on graft survival and portal flow. To explore the effects of excessive portal flow on graft survival in small-for-size liver transplantation, we transplanted partial liver grafts into syngeneic recipients. Results: In allogeneic combinations, graft survival among the shunt group was shortened compared with their control counterparts. The graft survival of the large shunt group was significantly lower than that of a small shunt or without shunt group in a syngeneic liver transplantation model. Portal blood pressure of the large shunt group was significantly lower than that of the small shunt group. In contrast, excessive portal flow resulted in dysfunction of liver graft in small-for-size liver transplantation. Conclusions: These results suggested that reduction in portal flow by portosystemic shunt lead to an acceleration of acute rejection and subsequent liver graft dysfunction, but it may be applicable to regulate the excessive portal flow in small-for-size transplantations. This study showed a valuable model mimicking the recipient with a portosystemic shunt.