Development of superior vena cava to pulmonary vein fistulae following modified Fontan operation: case report of a rare anomaly and embolization therapy.

A patient with double inlet single ventricle, L-transposition of the great arteries, and atrioventricular valve regurgitation developed progressive heart failure necessitating modified Fontan operation at 16 months of age. The procedure included replacement of the atrioventricular valve and pacemaker insertion. Eight years following the operation, the patient developed progressive cyanosis. Catheterization confirmed the presence of fistulae from the superior vena cava and innominate vein to the pulmonary veins as the cause of cyanosis. Coil embolization of several fistulae was performed successfully at catheterization. Contributing factors for fistula formation in Fontan patients are discussed, and therapy is reviewed.