N. M. Corbitt1, D. Hanto1, C. Baron1, P. Bream1, L. Gillis1, N. Wallace1 1Vanderbilt University Medical Center,Nashville, TN, USA
Introduction: Congenital Portosystemic Shunts (CPS) are extremely rare vascular anomalies, often discovered incidentally during imaging necessitated for evaluation of associated congenital anomalies. CPS can be classified according to the absence (Type 1 CPS) or presence (Type 2 CPS) of portal venous perfusion of the liver. They can be further classified according to anatomic variations as follows: Type 2A arise from left or right portal vein (PV), Type 2B arise from the PV, and Type 2C arise from splanchnic veins. CPS are associated with hyperammonemia, hepatic masses, and a variety of congenital anomalies. Closure can result in portal hypertension. We hypothesize that portal venography and temporary balloon occlusion is required to distinguish between type 1 and 2 CPS and temporary balloon occlusion (TBO) testing can determine if CPS are amenable to endovascular closure.
Methods: We report five new cases of CPS with a variety of illustrative presentations. All patients were diagnosed with CPS during childhood using ultrasonography (US) and/or contrasted tomography (CT) imaging. Portal venography and TBO was performed to further characterize CPS and assess feasibility of shunt closure. CPS closure was performed endovascularly using Amplatzer plugs when a single CPS was present and the portal venous pressure was < 20 mmHg.
Results: Associated anomalies were universally present. Five children had hyperammonemia and 4/5 had hyperbilirubinemia. In patient 4, US and CT imaging was suggestive of Type 1 CPS, however venography and TBO demonstrated intrahepatic PV filling. Also, two additional CPS were identified during TBO of the CPS between the PV and hepatic vein confluence, including a shunt between the SMV and the gonadal vein as well as a shunt between the SMV and right renal vein. In patient 5, venography demonstrated a CPS between the SMV-SV confluence and the IVC-right atrium confluence consistent with pre-procedural imaging. TBO of the CPS failed to demonstrate portal venous capillary filling characteristic of Type 1 CPS. Three patients underwent successful endovascular shunt closure using Aplatzer plugs and demonstrated subsequent resolution of hyperbilirubinemia and hyperammonemia. Three patients had hepatic lesions including foci of nodular hyperplasia. Notably, patient 3 had resolution of hepatic lesions following CPS closure.
Conclusion: TBO of CPS can be used to identify intrahepatic portal venous perfusion. Endovascular CPS closure can successfully reverse hepatic deprivation of portal venous flow in Type 2 CPS with resultant correction of hyperammonemia and hyperbilirubinemia. We suspect CPS closure could reduce hepatic malignancy potential by contributing to resolution of associated predisposing hepatic hyperplasia.
