The grade of pre-transplant portal vein thrombosis in liver transplant recipients impacts graft and patient survival
Safwan M, Sobolic M, Nagai S, Schilke R, Collins K, Yoshida A, Abouljoud M, and Rizzari M. The grade of pre-transplant portal vein thrombosis in liver transplant recipients impacts graft and patient survival. Am J Transplant 2018;18(Suppl 4):975-976.
Am J Transplant
Background: Portal vein thrombosis (PVT) in the pre-transplant (pretx) setting makes liver transplantation technically challenging and is also known to affect post transplant outcomes. Few studies describe the impact of the grade of PVT on morbidity and post transplant survival. Methodology: Case records of all liver transplant recipients with known pretx PVT from Jan 2010 to May 2017 (n=95) were reviewed. All recipients had PVT grades 1 to 3 (Yerdel classification) hence were divided into two groups, those with Grade 1 (n=56) and those with Grade 2 or 3 (n=39). Demographics, graft, operative and intraoperative characteristics were analyzed with postoperative outcomes. Results: Demographic characteristics were similar in both groups. Intraoperative factors such as cardiac output, central venous pressure, pulmonary artery pressure and transfusion requirements were also similar. Postoperative PVT incidence rates were higher in Grade 2/3 group but this was not statistically significant (17.9% Vs 8.9%, p=0.42). In terms of biliary strictures, higher cumulative rates at 6 months, 1 year and 2 years were observed in Grade 2/3 group compared to Grade 1 group (26.2% Vs 16.3%, 33.1% Vs 18.4% and 40.5% Vs 18.4% respectively, p=0.037). Grade 2/3 group also had a higher instantaneous 5-year graft loss risk (HR 3.0, CI 1.01-9.06, p=0.048) and overall instantaneous mortality risk after transplant (HR 2.97, CI 1.03-8.53, P=0.043) compared to Grade 1. Other postoperative complications such as hepatic artery thrombosis, early allograft dysfunction, bile leak rates, early and late rejection rates and hospital stay were similar. On multivariate analysis, grade 2/3 PVT (HR 3.6, CI 1.18-11.03, p=0.025) and bile leak (HR 4.47, CI 1.5-13.3, p=0.007) were the only factors associated with worse 5-year graft survival. Pre (HR 0.17, CI 0.02-1.4, p=0.1) and post transplant anticoagulation (HR 0.53, 0.16-1.7, p =0.3) appear to improve graft survival but there weren't statistically significant. Conclusions: Higher PVT grades may be an independent negative predictor of liver allograft and patient survival. Post-transplant bile leak may be also be a negative predictor for allograft survival. Pre and post transplant anticoagulation appear to have protective effects on graft survival.