Successful Biventricular Repair in Left Isomerism With Hepatic Vein Drainage to the Left-Sided Atrium

Left isomerism with ipsilateral hepatic venous drainage to the right- and left-sided atria is rare and presents complex cardiac anatomy for surgical planning of biventricular repair. This case presents a biventricular repair, guided by 3D modeling, in a patient with left isomerism, balanced complete atrioventricular septal defect (CAVSD), interrupted inferior vena cava with azygos continuation, and ipsilateral hepatic venous drainage to the right- and left-sided atria. Postnatal echocardiogram and cardiac catheterization confirmed balanced CAVSD, normal filling pressures, pulmonary overcirculation, and elevated pulmonary vascular resistance, favoring staged repair with initial pulmonary artery banding. Patient-specific 3D models allowed direct observation of the complex venous drainage into the left-sided atrium and planning of an intra-atrial baffle. At 11 months, the patient underwent biventricular repair using a 2-patch technique and intracardiac baffling. Intraoperative imaging showed no residual shunt, excellent atrioventricular valve function, and unobstructed venous drainage. This case demonstrates the value of 3D modeling in guiding biventricular repair in complex anomalous venous anatomy.