HEPATIC ARTERY THROMBOSIS AFTER LIVER TRANSPLANTATION IN CHILDREN UNDER 5 YEARS OF AGE

Abstract
The incidence of hepatic artery thrombosis (HAT) following orthotopic liver transplantation in children varies from 4% to 26% and represents a significant cause of graft loss1. The purpose of this study was to analyze the risk factors for HAT following liver transplantation in children less than 5 years old. Seventy-three transplants were performed in 62 children under 5 years of age, including 16 for acute hepatic failure, 46 for chronic liver disease, and 11 retransplants. Twenty-four whole liver grafts (WLG) and 49 reduced size grafts (3 right lobes, 16 left lobes, and 30 left lateral segments) were transplanted. The recipient common hepatic artery was used to provide arterial inflow in 22 transplants and an infrarenal iliac conduit in 51 transplants. The overall incidence of HAT was 8 out of 73 transplants (11%). The cold ischemia time (14.3±3.03 hr) in this group was significantly longer than the cold ischemia time for those without HAT (11.7±3.94 hr) (P=0.049). The incidence of HAT for whole and reduced grafts was 25% (6/24) and 4% (2/49), respectively (P=0.01). HAT occurred in 6 of 22 grafts (27.3%) revascularized from the recipient common hepatic artery, compared with 2 of 51 grafts (3.9%) using an infrarenal arterial conduit (P=0.008). The combination of recipient hepatic arterial inflow to a WLG resulted in HAT in 50% (6/12), whereas there were no cases of HAT with an iliac conduit to a WLG (P=0.01). Of the eight patients with HAT, five are alive (median follow-up, 20 months; range, 7-27 months). Five patients were retransplanted, three within the first 2 weeks and two at 4 and 5 months for abnormal liver function in association with clinical and histological features of chronic rejection. Prolonged cold ischemia time and use of a whole graft with recipient hepatic arterial inflow are risk factors for developing HAT. The use of reduced size grafts and infrarenal iliac arterial conduits are associated with a low incidence of HAT.