Background/purpose: A left lobe graft from a small donor will not usually fulfill the metabolic demands of a larger recipient in adult-to-adult living-donor liver transplantation (LDLT). One solution to this problem is to use a right lobe graft. However, the necessity of middle hepatic vein (MHV) outflow drainage from the anterior segment (AS) of a right lobe graft has not yet been clearly described in the literature. From July 1997 to February 1998, five right lobe grafts without MHV outflow drainage were implanted in five adult recipients. The graft weights ranged from 650 to 1000 g, and their volumes ranged from 48% to 83% of the ideal liver mass of the recipients. Two grafts showed severe congestion of the AS immediately after reperfusion, followed by prolonged massive ascites and severe liver dysfunction in each patient postoperatively. Eventually, one patient died of sepsis, on posttransplant day 20, demonstrating progressive hepatic dysfunction.
Methods: Subsequently, since March 1998, 176 of 208 adult recipients who received a right lobe graft, while demonstrating sizable (greater than 5-mm diameter) MHV tributaries underwent reconstruction of MHV outflow drainage, using the recipient's own autogenous or cryopreserved cadaveric interposition vein grafts.
Results: In 170 of the 176 recipients, AS congestion was not demonstrated on enhanced liver computerized tomography (CT) or Doppler ultrasonography (USG) postoperatively, and the patency rate of interposition vein grafts was 96.6% on day 30 posttransplant.
Conclusions: A right lobe graft without MHV outflow drainage might result in severe congestion of the AS, which could lead to the patient's death in an extreme situation. Preservation of MHV outflow drainage in a right lobe graft is possible by two harvesting methods: an extended right lobe (ERL)graft, in which the MHV trunk is included in the graft, and a modified right lobe (MRL) graft, in which venous tributaries of the MHV are reconstructed via interposition vein grafts into the recipient's hepatic venous system. From the viewpoint of donor safety, the ERL graft increases the donor's risk more than the MRL graft, because the remaining left liver lobe of the donor does not possess an MHV. Here, we introduce our experiences of MRL grafts in adult-to-adult LDLTs.