Mesoportal bypass: a unique operation for mesenteric hypertension.

A 47-year-old man was referred for evaluation and treatment of gastrointestinal variceal bleeding and possible transjugular intrahepatic portal-systemic shunting. Intrahepatic manometry disclosed a normal portal pressure, but selective mesenteric arteriography revealed occlusion of the superior mesenteric, splenic, and inferior mesenteric veins. Duodenal and gastric varices were noted, but no esophageal varices were seen. The portal vein was clearly patent. At surgery, a 2 cm mass was found at the superior mesenteric vein-splenic vein juncture, and subsequent pathologic examination confirmed the presence of suture material within dense fibrous tissue as the probable cause for this rare condition. The surgical procedure performed was a superior mesenteric vein-to-portal vein bypass, employing ringed expanded polytetrafluoroethylene. Graft patency and function have been confirmed postoperatively by means of both venous-phase mesenteric arteriography and duplex imaging. The surgical procedure was novel, in that it was possible to decompress the hypertensive mesenteric circulation from the distal superior mesenteric vein directly into the portal vein with a prosthetic bypass. The physiologic benefit of this operation is clear: the avoidance of the encephalopathic syndrome and the facilitation of hepatopetal blood flow.