Prehepatic portal hypertension with aneurysm of the portal vein: unusual but treatable malformative pattern.

INTRODUCTION: Portal vein aneurysms (PVAs) are usually located at the vein trunk or at its bifurcation, rarely intra-hepatic, or at the umbilical portion. Etiology remains unclear.

METHODS: Three children with PVA were identified over a 5-year period. PVA anatomy was assessed by Doppler Ultrasound, Angio CT/MRI, and trans-jugular retrograde portography.

RESULTS: Three children with intrahepatic PVA (including the umbilical portion) were identified during assessment for pre-hepatic portal hypertension: all had splenomegaly and hypersplenism. One presented with massive variceal bleeding. In two cases, a portal vein cavernoma was found, and in the third a severe stricture at the portal bifurcation was observed. Restoration of portal venous flow was achieved by a meso-Rex bypass in two cases and transposing the PV into the Rex in one. High hepatopetal portal flow was restored immediately, with follow-up confirming long-term patency and resolution of signs of portal hypertension with time.

CONCLUSIONS: These original observations suggest a common initial malformative pattern consisting of a portal venous stricture/web causing a post-stenotic aneurysmal dilatation of the intrahepatic portal branches complicated by thrombosis and cavernomatous transformation of the portal vein trunk. Importantly, the Meso-Rex bypass allows restoring a normal portal flow and cures the portal hypertension.