Conversion of atriopulmonary Fontan to extracardiac total cavopulmonary connection improves cardiopulmonary function

Background: Experimental studies showed that extracardiac total cavopulmonary connection provides superior hemodynamics than atriopulmonary Fontan. Methods: We prospectively assessed the impact of conversion of atriopulmonary Fontan to extracardiac total cavopulmonary connection on exercise capacity and cardiac function in 6 consecutive patients. Results: Six months after conversion to extracardiac total cavopulmonary connection, we observed an increase in peak oxygen uptake in all patients (p = 0.01;+ 17%). This improvement was associated to an increase of peak O₂ pulse (p = 0.01;+16%), but no change in peak heart rate, arterial oxygen saturation at peak exercise, and pulmonary function. Ventricular ejection fraction did not change significantly after surgery. Conversion was associated with an improvement in heart failure symptoms as assessed by the New York Heart Association classification. Patients who had undergone additional anti-arrhythmia surgery for atrial fibrillation had no recurrence of arrhythmia at follow-up. Conclusion: Data indicate that conversion to extracardiac total cavopulmonary connection is associated with an improvement of cardiopulmonary function and heart failure symptoms. Improved exercise capacity is due to an increase in O₂ pulse and may reflect an improved cardiac stroke volume after the operation.