Approach to anatomic variations of the graft portal vein in right lobe living-donor liver transplantation.

Right lobe living-donor liver transplantation (LDLT) is often not attempted in donors with anomalous portal venous branching (APVB). The authors describe their experience with portal vein (PV) reconstruction in 17 cases of APVB in right lobe LDLT. From July 1997 to December 2001, 214 right liver LDLT were performed at the Asan Medical Center. Seventeen of the donors had APVB and successfully underwent right lobectomy. The APVB were type II (trifurcation) in nine cases, type III (independent posterior segmental branching from main PV trunk) in seven, and unclassified in one. All 17 donors and recipients are alive, with good liver function. In type II APVB, the donor PV branches were obtained with separate openings that were joined as a common orifice at the back table in two, with a discoid-patch single opening in four, and with one common opening in three. In type III APVB, the donor PV were divided with two openings in four and with a discoid-patch single opening in three. The discoid-patch defect in the remnant PV was repaired with a vein patchplasty in two donors and resected with end-to-end anastomosis in five. However, one donor developed portal vein thrombosis (PVT) that was managed successfully by re-exploration and insertion of a metallic vascular stent. Of the four type III APVB obtained with two separate PV openings, the first two liver grafts were each reconstructed as double PV anastomoses. One of them required re-exploration because of PVT. In the two succeeding cases, a Y-graft interposition technique using a cryopreserved cadaveric iliac vein or the recipient's own portal confluence was successfully applied. To minimize the risk of PVT in donors with APVB, discoid-patch excision followed by repair with vein patchplasty or segmental resection should be avoided. Individual division of the PV branches creating two separate openings instead is recommended. To decrease the recipient's risk of PVT, interposition Y-graft venous reconstruction at the back table is superior to double PV anastomoses.