Right Lobe Versus Left Lobe Living Donor Liver Transplantation: A Systematic Review and Meta-analysis of Donor and Recipient Outcomes

Background. Living donor liver transplantation (LDLT) is an established treatment for advanced liver disease. Whether right lobe (RL) or left lobe (LL) LDLT provides the best outcomes for donors and recipients remains contentious. Methods. MedLine, Embase, PubMed, and Cochrane Central were searched to identify studies comparing RL- and LL-LDLT and reporting donor and/or recipient outcomes. Effect sizes were pooled using random-effect meta-analysis. Meta-regressions were used to explore heterogeneity. Results. Sixty-seven studies were included. RL donors were more likely to experience major complications (relative risk [RR] = 1.63; 95% confidence interval [CI] = 1.30-2.05; I²= 19%) than LL donors; however, no difference was observed in the risk of any biliary complication (RR = 1.41; 95% CI = 0.91-2.20; I²= 59%), bile leaks (RR = 1.56; 95% CI = 0.97-2.51; I²= 52%), biliary strictures (RR = 0.99; 95% CI = 0.43-1.88; I²= 27%), or postoperative death (RR = 0.51; 95% CI = 0.25-1.05; I²= 0%). Among recipients, the incidence of major complications (RR = 0.85; 95% CI = 0.68-1.06; I²= 21%), biliary complications (RR = 1.10; 95% CI = 0.91-1.33; I²= 8%), and vascular complications (RR = 0.79; 95% CI = 0.44-1.43; I²= 0%) was similar. Although the rate of small for size syndrome (RR = 0.47; 95% CI = 0.30-0.74; I²= 0%) and postoperative deaths (RR = 0.62; 95% CI = 0.44-0.87; I²= 0%) was lower among RL-LDLT recipients, no differences were observed in long-term graft (hazard ratio = 0.87; 95% CI = 0.55-1.38; I²= 74%) and overall survival (hazard ratio = 0.86; 95% CI = 0.60-1.22; I²= 44%). Conclusions. LL donors experience fewer complications than RL donors, and LL-LDLT recipients had similar outcomes to RL-LDLT recipients. These findings suggest that LL-LDLT offers the best outcomes for living donors and similar outcomes for recipients when measures are taken to prevent small for size syndrome.