Massive systemic venous thrombosis after Fontan operation: report of a case.

A 7 year old boy with single ventricle with pulmonary stenosis underwent a modified Fontan procedure. He had a very stormy postoperative course complicated by continued pleural effusion, hepatomegaly, and chylothorax. He eventually died after an atrial septum reopening. At autopsy, massive thrombi were found in the inferior vena cava, right atrium, and pulmonary artery. This complication was probably due to multiple factors, but a routine anticoagulation therapy may be required after Fontan procedure.