Hepatic venous territory mapping in living donor liver transplantation using right liver graft: an objective parameter for venous reconstruction

Purpose: This study evaluated the clinical implication of hepatic venous territory mapping in living donor liver transplantation. Methods: Living donor liver transplantations performed using right graft since 2017 were included. Hepatic venous volume mapping was started in 2019. Risk factors for graft failure and overall survival were analyzed. Analysis for factors related to occlusion of reconstructed vein was performed. Results: Among 445 patients included, 213 underwent hepatic venous mapping. Hepatic venous mapping itself was not a significant factor for graft (hazard ratio [HR], 0.958; 95% confidence interval [CI], 0.441–2.082; P = 0.913) and overall survival (HR, 0.627; 95% CI, 0.315–1.247; P = 0.183). Inferior hepatic vein occlusion was a significant risk factor for both graft survival (HR, 8.795; 95% CI, 1.628–47.523; P = 0.012) and overall survival (HR, 11.13; 95% CI, 2.460–50.300; P = 0.002). In a subgroup with middle hepatic vein reconstruction, occlusion was a significant risk factor for overall survival (HR, 3.289; 95% CI, 1.304–8.296; P = 0.012). In patients with middle hepatic vein reconstruction whose venous territory volumes were measured, right anterior volume of ≥300 cm³ was protective for vein occlusion (OR, 0.317; 95% CI, 0.152–0.662; P = 0.002). In patients with V5 reconstruction, V5 volume of ≥150 cm³ was protective for vein occlusion (OR, 0.253; 95% CI, 0.087–0.734; P = 0.011). Conclusion: Inferior and middle hepatic vein reconstruction has significant impact on clinical outcome. Hepatic venous territory mapping can provide an objective measure for successful reconstruction of venous branches.