Objectives: In patients after the Fontan operation, we determined risk factors for late failure and for intra-atrial re-entrant tachycardia at 15 to 20 years' follow-up. Midterm results after electrophysiologic ablation therapy for these tachycardias were also evaluated.
Methods: Current follow-up was available in 162 patients (2005 patient-years) with a wide range of underlying diagnoses operated on between February 1978 and May 1995. Risk factor analysis included patient-related and procedure-related variables, with late failure and the incidence of re-entrant tachycardia as outcome parameters.
Results: Forty late failures were observed (2.0 per 100 patient-years). At 15 years, Kaplan-Meier estimated survival was significantly (P =.007) better for patients with tricuspid atresia (93%) compared with that for patients with complex congenital malformation (71%). The sole multivariable risk factor for Fontan failure was the type of underlying diagnosis. At 20 years' follow-up, overall freedom from tachycardia was estimated to be 46% +/- 12%. Acute success of electrophysiologic ablation was seen in 25 (83%) of 30 patients, and Kaplan-Meier estimated freedom from recurrent tachycardia was 81% +/- 10% at 3 years. Multivariate analysis identified duration of Fontan circulation as the sole risk factor for re-entrant tachycardias.
Conclusion: After the modified Fontan operation, long-term survival in patients with tricuspid atresia was significantly better compared with that in patients with complex congenital malformations. As first-choice therapy for atrial re-entrant tachycardias, we recommend electrophysiologic ablation therapy.