Variations in the origin of middle hepatic artery: a cadaveric study and implications for living donor liver transplantation.

Living donor liver transplantation has been associated with severe vascular complications like hepatic artery thrombosis, which commonly involves the hepatic segment 4. Most authors have defined the artery to this segment as the middle hepatic artery. The present study was undertaken to characterize the origin of middle hepatic artery and classify the variations observed in cadaveric livers, and also to analyze the significance (if any) of the findings in relation to living donor liver transplantation. The study was conducted on 125 adult livers, without macroscopic abnormalities, retrieved from human cadavers (age, 55-78 years; male, 77; female, 48) obtained from clinical wards. The hepatic arterial system was exposed, the origin of the middle hepatic artery was identified in each liver specimen and the variations observed in its origin were noted across all the specimen. Six types of hepatic arterial configurations were observed based on variations in the origin of middle hepatic artery, taking into consideration the presence of accessory hepatic arteries. It was noted in 19 (15.2%) livers that in the presence of an accessory left hepatic artery, the middle hepatic artery arose as a sub-branch of the right hepatic artery. Presence of the above hepatic arterial configuration in the donor could possibly be associated with an increased risk of intra-operative injury to the middle hepatic artery during right/left lobe living donor liver transplantation and this may subsequently lead to serious post-operative vascular complications like hepatic artery thrombosis.