Transcatheter Occlusion of Hepatic Vein-Atrial Communication After Modified Fontan in a Child Post Kawashima Surgery

The hepatic vein-azygos vein connection is a rare Fontan modification used in patients with single ventricle physiology and interrupted inferior vena cava, following an initial Kawashima procedure. We report an unusual case of severe, late-onset hypoxemia due to recanalization of a hepatic vein-atrial communication after this operation.

A girl with heterotaxy, mesocardia, unbalanced atrioventricular septal defect, and interrupted inferior vena cava underwent Kawashima surgery at 1 year of age, followed by modified Fontan completion at 4 years, in which hepatic veins were connected to the azygos vein. Nine years later, she presented with profound cyanosis (SpO₂ 35% to 40%) and polycythemia. Imaging demonstrated recanalization of hepatic vein-atrial communication resulting in significant right to left shunt and diffuse pulmonary arterio-venous malformations. Transcatheter closure of the communication using a 12-mm muscular ventricular septal defect occluder improved oxygen saturation to 65% with symptomatic relief.

The hepatic vein-azygos vein connection represents an uncommon Fontan modification designed to ensure uniform distribution of hepatic venous flow to both the lungs. Late recanalization of a hepatic vein-atrial communication following this procedure has not been previously reported. In our case, transcatheter occlusion of the communication successfully redirected the hepatic venous flow to the pulmonary circuit.

We describe a previously unreported complication of a rare Fontan modification. Transcatheter closure of a recanalized hepatic vein-atrial communication can effectively restore Fontan physiology and improve systemic oxygenation.