Fontan Conversion to One and One Half Ventricle Repair

Background. In patients with a modified Fontan connection, particularly the right atrial to right ventricular connection, the pulmonary ventricle may enlarge with time. Methods. Between January 1990 and December 2006, 10 patients (median age, 24 years) underwent Fontan conversion to a one and one half ventricle repair. Tricuspid atresia was the most common diagnosis (n = 7). The right atrial to right ventricular connection was present in 8 patients; 3 patients had a prior bidirectional cavopulmonary anastomosis. Preoperative median right atrial pressure was 14 mm Hg (range, 12 to 20 mm Hg). Indications for surgery were exercise intolerance, arrhythmias, and conduit obstruction. Echocardiography showed moderate right ventricular hypoplasia, with right atrial to right ventricular regurgitation. The conversion included closure of septal defects, tricuspid valve replacement (n = 8), bidirectional cavopulmonary anastomosis (n = 7), valved right ventricular outflow tract reconstruction (n = 2), and arrhythmia surgery (n = 6). Results. There was no early mortality. There was one reoperation for residual ventricular septal defect. Prolonged chest tube drainage occurred in 2 patients. Postoperative right atrial pressure ranged from 8 to 14 mm Hg (median, 10 mm Hg; p = 0.02). Median follow-up was 8 years. There was no late mortality. Nine patients are in New York Heart Association class I or II, and 1 patient has biventricular failure and was awaiting transplantation. There were two late reoperations, 1 for thrombosis of the mechanical tricuspid valve prosthesis and 1 for obstruction of the valved right ventricular outflow tract conduit. Three patients had recurrent atrial arrhythmias requiring cardioversion. Conclusions. Fontan conversion to one and one half ventricle repair is feasible in selected patients with a failing Fontan circulation. Operation can be performed with low early mortality. Arrhythmia surgery should be performed routinely. Quality of life is excellent. (Ann Thorac Surg 2012; 94: 1269-74) (C) 2012 by The Society of Thoracic Surgeons