Hepatic Congestion-linked Intrahepatic Biliary Strictures After Living Donor Liver Transplantation

BACKGROUND: Intrahepatic biliary stricture (IHBS) is a serious complication after living donor liver transplantation (LDLT) that often necessitates repeated interventions and compromises graft survival. Graft hepatic congestion (GHC) has been implicated, yet its independent impact on IHBS and its anatomical relevance, distinct from anastomotic stricture, remain incompletely defined. METHODS: We retrospectively analyzed 721 adult recipients who underwent right-liver LDLT with single-duct reconstruction between 2011 and 2018. For the primary analysis, ABO-incompatible transplants and cases with isolated anastomotic stricture were excluded. GHC was evaluated using early postoperative computed tomography and categorized by anatomical extent as none, single-section, or both-section congestion. Anatomical concordance between congestion extent and IHBS distribution was assessed. Fine-Gray competing risk regression identified independent predictors of IHBS, treating death and retransplantation as competing events. Time-dependent analyses distinguished persistent from transient congestion. RESULTS: GHC was common and demonstrated a stepwise association with IHBS according to anatomical extent. The spatial distribution of IHBS closely corresponded to congestion location, supporting anatomical concordance. In competing risk analyses, increasing congestion extent remained an independent predictor of IHBS, with the highest risk observed in both-section congestion. Persistent congestion conferred a significantly higher IHBS risk than transient congestion (hazard ratio, 2.12; 95% confidence interval, 1.29-3.49). Overall survival was poorest among patients with extensive IHBS involving both anterior and posterior sections. CONCLUSIONS: Anatomically defined GHC is a reproducible and clinically meaningful determinant of IHBS after right-liver LDLT in an ABO-compatible setting.