RADIOFREQUENCY CATHETER ABLATION OF RIGHT-VENTRICULAR TACHYCARDIA LATE AFTER REPAIR OF CONGENITAL HEART-DEFECTS

Background Ventricular arrhythmias after repair of congenital heart de fects are a common finding and possibly contribute to sudden death in these patients. Optimal antiarrhythmic management has not yet been def ined. Methods and Results The study population consisted of 16 patient s in whom ventricular arrhythmias occurred 11 to 42 years after comple te surgical repair of congenital heart defects. Fifteen patients had a history of symptomatic sustained or nonsustained ventricular tachycar dia, and 1 had frequent nonsustained ventricular tachycardia. The diag nostic mapping procedure to identify the origin of the arrhythmia incl uded pace mapping during sinus rhythm, activation mapping, and pacing interventions during ventricular tachycardia. Catheter ablation was ca rried out by means of radiofrequency energy in the temperature-control led mode. The follow-up period was 6 to 33 months (mean, 16 months). A right ventricular origin of the tachycardia in the surgically correct ed area could be determined in all patients. Catheter ablation was car ried out without complications. Immediate noninducibility was achieved in 15 of the 16 patients. One patient in whom the tachycardia was aga in inducible at repeat stimulation 1 week later was successfully treat ed with amiodarone. Eleven patients were taken off antiarrhythmic drug s. During follow-up, none of them had a recurrence of the tachycardia that had been ablated. Conclusions In patients with symptomatic or fre quent ventricular tachycardia late after complete surgical repair of c ongenital heart defects, catheter ablation by means of radiofrequency energy is feasible and safe and thus might be taken into consideration far these patients. Short-term follow-up results are promising.