Mesenteric Vein Access for OPVT-Related Recurrent Variceal Bleeding: An Ambispective Cohort

Occlusive portal vein thrombosis (OPVT) is defined as complete thrombosis of the main portal vein trunk, resulting in interruption of portal venous inflow and representing a severe form of portal vein thrombosis. Although some patients may remain asymptomatic for prolonged periods because of collateral compensation, many develop clinically significant portal hypertension when collateral flow is inadequate-most notably gastroesophageal variceal bleeding and ascites. Gastroesophageal variceal bleeding is a major cause of morbidity and mortality and is often more difficult to control, with a higher risk of rebleeding, than variceal bleeding in patients without portal vein thrombosis.

Transjugular intrahepatic portosystemic shunt (TIPS) is an established minimally invasive therapy for complications of portal hypertension. In OPVT, however, technical feasibility often hinges on successful portal vein recanalization. Multiple adjunctive techniques have been developed to improve feasibility in selected patients, including percutaneous transhepatic or transsplenic portal vein recanalization TIPS (PVR-TIPS), portal cavernous collateral-caval shunt procedures, mesenteric-caval or spleno-caval shunts, and surgically assisted hybrid approaches. Despite these advances, a meaningful subset of patients remain poor candidates because of extensive intrahepatic portal branch thrombosis, absence of a feasible splenic puncture route, prior splenectomy, or prohibitive risk for laparotomy-assisted hybrid procedures (e.g., in patients with limited hepatic reserve and/or ascites).

This study will evaluate ultrasound-guided percutaneous mesenteric vein (MV) puncture as an adjunctive access strategy to enable interventional decompression of the portal venous system in OPVT. Using real-time ultrasound, percutaneous MV access is obtained to establish an antegrade working channel. This channel is then used to facilitate portal vein recanalization and/or shunt creation when standard access routes are not feasible or have failed.

Study design and setting: Ambispective, exploratory, single-center clinical study.

Population: Patients with imaging-confirmed OPVT and recurrent gastroesophageal variceal bleeding, particularly those in whom conventional interventional access routes (e.g., transjugular-only approaches, percutaneous transhepatic access, or transsplenic access) are limited, infeasible, or have been unsuccessful.

Intervention (Stepwise Intra-procedural Strategy)

After establishing MV access under ultrasound guidance, operators will follow a predefined escalation algorithm based on intra-procedural anatomy and technical feasibility:

MV-assisted PVR-TIPS (preferred): Antegrade catheter/guidewire manipulation via MV access to attempt recanalization of the occluded main portal vein trunk. A catheter or balloon may be positioned as a target to facilitate completion of a standard TIPS via the transjugular route.

MV-assisted collateral-to-caval shunt (secondary): If main portal vein recanalization is not achievable, selective catheterization of an eligible collateral (e.g., diameter ≥6 mm) may be performed, with target-marker assistance to create a collateral-to-inferior vena cava shunt via the transjugular route.

Extrahepatic MV-to-caval shunt (backup): If neither main portal vein recanalization nor a suitable collateral is available, an extrahepatic MV-to-inferior vena cava shunt tract may be created through the established MV access as an alternative portal decompression strategy.

Outcomes (Overview) The study will assess: (1) technical feasibility (e.g., successful MV access; successful creation of a functioning shunt via any pathway), (2) procedural safety (peri-procedural and follow-up complications), and (3) clinical effectiveness, including control of portal hypertension-related bleeding (e.g., rebleeding during follow-up) and other manifestations of portal hypertension, as applicable.