Seven-year follow-up after catheter ablation of atrioventricular nodal re-entrant tachycardia

BACKGROUND: Radiofrequency catheter ablation is considered to be a curative therapy for patients with atrioventricular nodal re-entrant tachycardia (AVNRT). Nevertheless, there is little information available with respect to long-term results and the consequences of catheter ablation. The present study aimed to assess the long-term results (a minimum of 5 years) and clinical events. PATIENTS AND METHODS: The recurrence rate of AVNRT, the development of late atrioventricular block and the presence of other arrhythmias (atrial flutter and fibrillation) were assessed in 131 consecutive patients who were undergoing catheter ablation between January 1992 and December 1998. RESULTS: During a mean follow-up of 7.2 +/- 2.5 years, tachycardia recurred in 13 patients (10%) after a median time of 6 months (interquartile range 4-24 months) and a second procedure was perfomed. Atrioventricular block occurred in two patients (1.5%) after 1 and 13 months. Atrial fibrillation recurred in seven (44%) of 16 patients in whom atrial fibrillation or flutter was present before ablation after a median of 12 months (interquartile range 9-15 months). Overall, all these events occurred after a median of 9 months (interquartile range 4-17 months). Subsequently, no event related to the arrhythmia or to the procedure was observed. A new onset atrial fibrillation, probably not related to AVNRT, occurred late in the follow-up in a further three patients. CONCLUSIONS: Arrhythmic events are not infrequent after catheter ablation of AVNRT during the early years after ablation, but they are unlikely during the subsequent long-term follow-up.