Regeneration rate of left liver grafts in adult living donor liver transplant

Objective: Appropriate graft weight is important in liver transplant to provide better graft regeneration and to avoid small-for-size syndrome with graft failure. Generally, to protect the donor, the left liver is always selected as the graft. The aim of this study is to evaluate the regeneration rate of the left lobe liver graft in adult living donor liver transplantation (ALDLT).

Patients and methods: The records and preoperative and postoperative images within 6 months after liver transplantation were reviewed for 9 left and 145 right liver grafts ALDLT enrolled in this study. We calculated the graft volume at 6 months after transplantation divided by the standard liver volume as the regeneration ratio. The regeneration rate of the group with a left liver graft ALDLT was compared with our right liver graft group.

Results: The liver graft regeneration ratio of the left lobe was 85.3+/-11.0 (range, 61-97), slightly lower than the right liver graft (91.2+/-12.6%; range, 58-151). In the graft-recipient body weight ratio (GRWR)>1, the regenerative rate was slightly higher than the group of GRWR<1. The regeneration ratio was proportional to spleen volume and portal inflow (P=.039).

Conclusion: Either the right or left liver graft can achieve sufficient regeneration in ALDLT. However, there was a slightly lower regeneration rate among the left liver graft and GRWR<1 groups. Spleen size, a major factor contributing to portal inflow, may directly trigger graft regeneration after transplantation with a linear correlation in growth.