[Long-term efficacy of radiofrequency catheter ablation in atrial tachycardia]

Radiofrequency ablation has shown to be an effective treatment for supraventricular tachycardias including flutter and atrial tachycardia, however the clinical information available on atrial tachycardia is limited. The aim of this study was to evaluate the immediate and long term effectiveness of radiofrequency ablation in patients with atrial tachycardia and to establish predictors of effectiveness and arrhythmia recurrence.

We analyzed a series of 126 procedures of atrial tachycardia ablation in 117 patients (69% women) with a mean age of 50 +/- 19 years.

Ninety-one percent of the foci were located in the right atrium. A mean of 6 applications were necessary to achieve an efficacy of 74% during the first procedure with a total of 80%. The only predictor of ablation success was the number of foci being smaller in multifocal compared to unifocal (p < 0.01) whereas for recurrences a less premature electrogram at the application point (p = 0.02) was predictive of ablation success. Over a follow-up of 34 +/- 19 months 7.4% of patients had recurrent atrial tachycardia. The probability of recurrence at one year calculated by the Kaplan-Meier method was 12%. Seventy-one percent of the recurrences occurred during the first 3 months after ablation.

Ablation is an effective, safe procedure for short and long term treatment of patients with atrial tachycardia. Effectiveness depends on the number of foci while the recurrence rate is related to the prematurity of atrial electrogram at the application point.