Modified Fontan operation for single ventricle with common atrium and abnormal systemic venous drainage: usefulness of an additional superior vena cava to pulmonary artery anastomosis.

In two patients (aged 15 and nine years old) with single ventricle, common atrioventricular valve, common atrium, and bilateral abnormally draining superior vena cava (SVC), a modified Fontan procedure was performed together with a SVC to pulmonary artery (PA) anastomosis. This avoided complex intraatrial septation. A bilateral anastomosis was carried out in one patient and a unilateral one in the other, the PA not being divided in either patient. This procedure provided simple intraatrial septation while avoiding possible obstruction of either the pulmonary or systemic blood pathways if complete intraatrial septation had been carried out.