Aims: In patients with surgical atrial septal defect (ASD) repair, late atrial flutters (AFLs), including cavotricuspid isthmus (CTI)-dependent and non-CTI-dependent scar-related flutter (AFL), are common. Radiofrequency ablation (RFA) of these arrhythmias has a high acute success rate. We aimed to characterize the long-term freedom from atrial arrhythmias in this population.
Methods: Twenty consecutive patients undergoing RFA for AFL late after ASD repair were included. Electrophysiological assessment included multipolar activation, entrainment, and electroanatomic mapping. Clinical, electrocardiograph, and Holter monitoring follow-up was conducted every 6 months.
Results: Mean age was 53 ± 13 years. Time from surgical repair to RFA was 29 ± 15 years. All patients had CTI-dependent AFL (20/20). There were 1.6 ± 0.7 arrhythmias per patient; other arrhythmias included non-CTI-dependent AFL (14), focal atrial tachycardia (two), and atrioventricular nodal reentry tachycardia (two). Acute success was obtained in 100%. Five patients with recurrent AFL (three CTI dependent, two non-CTI dependent) at 13 ± 8 months had successful repeat RFA. At 3.2 ± 1.6 years follow-up since the last procedure, 90% of patients with successful RFA for AFL remained free of their clinical arrhythmia. However, 30% of the original 20 patients had documented atrial fibrillation (AF) 2.1 ± 1.6 years after the last procedure; five (25%) required AF intervention. One stroke (5%) occurred in the context of late AF.
Conclusion: RFA of AFL occurring late after surgical ASD repair has a low long-term risk of recurrence, although 25% of patients required two procedures. However, there is a high late incidence of AF (30%), with an additional 25% of patients requiring intervention for AF. (PACE 2011; 34:431–435)