Surgical treatment of arrhythmias related to congenital heart diseases.

Background: Supraventricular arrhythmias complicate operated and unoperated congenital heart disease, especially when atrial dilatation coexists.

Methods: We evaluated the results of intraoperative ablation in a group of 23 patients with chronic supraventricular tachyarrhythmias (mostly intraatrial reentry) that were unresponsive to conventional medical therapy. All procedures were performed consecutively between September 1999 and November 2001. Ablation was done during redo operations (Fontan conversion to total cavopulmonary connection in 16 patients) in 18 patients and during primary surgical correction in 5 patients. The mean age at operation was 25 +/- 12 years (2 to 50 years). Cryoablation was done in 10 patients and radiofrequency ablation in 13 patients. Nineteen patients had ablation in one atrium and 4 had ablation in both atria. A generous atrial reduction was always performed at the end of the operation.

Results: The operative mortality rate was 13% (3 patients) from causes unrelated to ablation. In 20 survivors, the ablation was effective immediately. Eight patients required a permanent pacemaker. During a mean follow-up of 22 +/- 4 months, atrial arrhythmias recurred in 25% (5 patients) and were controlled with medical therapy, whereas 1 patient required pacemaker implantation.

Conclusions: Intraoperative treatment of unresponsive atrial tachyarrhythmias associated with operated or unoperated congenital heart disease is feasible and the midterm results are encouraging.