Association of donor anterior sector congestion area and neomiddle hepatic vein block with early allograft dysfunction after living donor liver transplantation: a retrospective cohort study

Background: Early allograft dysfunction (EAD) is an important complication after living donor liver transplantation (LDLT). In modified right lobe grafts, anterior-sector venous congestion may contribute to early graft dysfunction, but the clinical relationship between the intraoperatively observed congestion burden, neo-middle hepatic vein (neo-MHV) block, and EAD remains uncertain. Methods: We performed a retrospective single-centre cohort study of adult LDLT recipients receiving modified right lobe grafts from January 2017 through December 2025. The primary outcome was EAD according to the Olthoff criteria. The principal exposure was the intraoperatively estimated donor anterior-sector congestion area (%). Propensity score matching (PSM), multivariable logistic regression, and receiver operating characteristic (ROC) analysis were performed. Results: Among 1,184 recipients, 88 (7.4%) developed EAD. Mean congestion area was greater in recipients with EAD than in those without EAD (approximately 31% vs 22%), and the association persisted after PSM. In complete-case multivariable logistic regression (n=1,153; 85 EAD events), each 10-percentage-point increase in congestion was independently associated with higher odds of EAD (adjusted OR 1.52, 95% CI 1.29-1.79; p<0.001). Neo-MHV block was not independently associated with EAD. Congestion alone had modest discrimination (AUC 0.62). A data-derived 15% cut-off had 100% sensitivity and 32.8% specificity in the full cohort. Conclusion: Higher donor anterior-sector congestion was independently associated with EAD. Neo-MHV block was not significantly associated with EAD. The 15% congestion cut-off should be considered exploratory because discrimination was modest and external validation is lacking.