Anatomical Risk Factors for Portal Vein Complications Following Right Hepatectomy in Living Donors.

OBJECTIVE To determine the incidence, clinical outcomes, and anatomical risk factors of portal vein (PV)-related complications after right lobe donor hepatectomy (RLDH). SUMMARY BACKGROUND DATA With the increase in living donor liver transplantation, large-scale studies on donor morbidity have been conducted to ensure donor safety. However, reports evaluating PV-related complications following right hepatectomy in living donors are lacking. METHODS We analyzed the medical records of 4720 consecutive donors who underwent RLDH from July 1997 to December 2020 at our institution. The PV angle was classified according to the angulation between the main and left PV. Outcomes included the incidence of postoperative PV-related complications in living donors who underwent right hepatectomy and risk factors for PV-related complications after RLDH. RESULTS The incidence of PV-related complications following RLDH was 1.9% (n=88), including PV thrombosis (n=9) and stenosis (n=79). Donors with PV-related complications exhibited higher peak alanine aminotransferase levels than those without PV complications (P=0.023); however, peak total bilirubin (P=0.055), peak international normalized ratio (P=0.395), and postoperative hospital stays (P=0.117) were similar. Multivariate logistic regression revealed an angle between the main and left PV of <60° as a significant independent risk factor for PV-related complications (odds ratio: 6.250; P<0.001). Additionally, variant PV anatomy, absence of falciform ligament fixation, and a body mass index of >30 kg/m2 were identified as independent risk factors (P<0.001, P<0.001, and P=0.002, respectively). CONCLUSIONS Acute angulation between the main and left PV or variant PV anatomy is associated with an increased incidence of PV-related complications following RLDH.