Recanalized umbilical vein conduit for meso-Rex bypass in extrahepatic portal vein obstruction Marcelo E. Facciuto, MD, a Manuel I. Rodriguez-Davalos, MD, a Manoj K. Singh, MD, a Juan P. Rocca, MD, a Caroline Rochon, MD, a Wei Chen, MD, b Umadevi S. Katta, MD, c and Patricia A. Sheiner, MD, a Valhalla, NY Background. Meso-Rex bypass is used to treat patients with clinically important extrahepatic portal vein obstruction (EHPVO). Usually, an autologous left internal jugular vein graft is used to bypass the portal blood circulation from the superior mesenteric vein to the left portal vein. Other vascular conduits have included the autogenous saphenous vein, splenic vein, right gastroepiploic vein, and inferior mesenteric vein. Methods. A total of 20 umbilical veins with attached livers were harvested from 20 deceased liver donors. Umbilical veins were dilated mechanically and checked for patency and communication with the left portal vein. Vein length and diameter after dilatation were recorded. Cross-sections of 15 recanalized umbilical veins were processed by routine histologic examination and stained with hematoxylin and eosin, as well as processed by immunohistochemistry for CD31 and factor VIII antigens. Subsequently, 3 children with EHPVO underwent this modified meso-Rex bypass using the umbilical vein as a vas- cular conduit. Results. The mean length of harvested umbilical veins was 15 cm (range, 7--21); the mean length of recanalized and usable umbilical veins was 10 cm (range, 5--15). Recanalization was successful in 16 (80%) of the 20 donor umbilical veins. The mean diameter of the umbilical veins after serial dilatation and recanalization was 1.2 cm (range, 1--2). In 11 (73%) of the 15 recanalized vein specimens, the lumen was lined by endothelial cells. In 2 children, the vascular conduit was constructed entirely with native umbilical vein. In the remaining child, 3 cm of umbilical vein was preserved and anastomosed to a mobilized inferior mesenteric vein due to inadequate length. All 3 children had patent bypass and resolution of clinical manifestations of portal hypertension at a mean follow-up of 21 months. Conclusion. Meso-Rex bypass may prove to be a definitive treatment for patients with EHPVO. The use of native umbilical vein as a vein conduit achieved decompression of the splanchnic venous system and should be considered a natural alternative to other interposition vein grafts. (Surgery 2009;145:406-10.) From the Liver Transplant and Hepatobiliary Service, a Department of Radiology, b and Department of Pathology, c Westchester Medical Center, New York Medical College, Valhalla, NY EXTRAHEPATIC PORTAL VEIN OBSTRUCTION (EHPVO) is being recognized increasingly as a cause of extra- hepatic portal hypertension (EHPH) in children. Traditionally, portosystemic shunt procedures were reserved for patients who failed conservative measures (eg, endoscopic control of variceal bleeding) or who had clinically important hypersplenism. The introduction of the meso- Rex bypass, which redirects mesenteric blood flow into the liver. has changed the therapeutic ap- proach to EHPH. 1 With the meso-Rex bypass, EHPVO is circumvented by an autologous graft (classically the left internal jugular vein) inter- posed between the superior mesenteric vein and the left portal vein. Other vascular conduits also have been used, including the autogenous saphe- nous vein, splenic vein, right gastroepiploic vein, and inferior mesenteric vein. 2-6 In this study, we describe our efforts to assess the technical feasibility and effectiveness of a variant of the classical meso-Rex shunt in which the patient’s recanalized umbilical vein is used as an inflow conduit to the portal circulation. The round ligament is connected to the left portal vein. Accepted for publication December 15, 2008. Reprint requests: Marcelo E. Facciuto, MD, Liver Transplant and Hepatobiliary Service, Transplant Center, BHC-A Wing, Lower Level, 95 Grasslands Road, Valhalla, NY 10595. E-mail: facciutom@wcmc.com. 0039-6060/$ - see front matter Ó 2009 Mosby, Inc. All rights reserved. doi:10.1016/j.surg.2008.12.004 406 SURGERY