Anomalous hepatic vein anatomy of left lateral section grafts and customized unification venoplasty for pediatric living donor liver transplantation

Abstract

In liver transplantation, a left lateral section (LLS) graft may have an unusual variant left hepatic vein (LHV) anatomy. This study was designed to analyze the incidence of unusual LHV variants and to determine technical methods for effective reconstruction in infant recipients weighing approximately 10 kg or less. The study comprised 3 parts: an LHV variation analysis, a simulation-based design for the technical modification of graft LHV venoplasty, and its clinical application. The LHV anatomy of 300 potential LLS graft donors was classified into 4 types according to the number and location of the hepatic vein openings: (1) a single opening (n = 218 or 72.7%); (2) 2 large adjacent openings (n = 29 or 9.7%); (3) 2 adjacent openings, 1 large and 1 small (n = 34 or 11.3%); and (4) 2 widely spaced openings (n = 19 or 6.3%). Types 2 and 3 required wedged unification venoplasty, and type 4 required additional vein interposition. In a series of 49 cases using LLS grafts, the graft hepatic vein complication rate was 4.5% at 3 years; stenting was necessary for 1 of the 36 type 1 LHV grafts (2.8%) and for 1 of the 13 type 2-4 LHV grafts (7.7%, P = 0.46). A customized interposition-wedged unification venoplasty technique for coping with type 4 vein variations was developed with a simulation-based approach, and it was successfully applied to a 10-month-old male infant receiving an LLS graft with a type 4 LHV. In conclusion, nearly all LHV variations can be effectively managed with customized unification venoplasty. These venoplasty techniques represent beneficial surgical options as part of graft standardization for hepatic vein reconstruction in pediatric living donor liver transplantation.