Impact of radiofrequency catheter ablation of accessory pathways on the frequency of atrial fibrillation during long-term follow-up - High recurrencerate of atrial fibrillation in patients older than 50 years of age

Aims Atrial fibrillation represents a frequent and potentially life-threate ning arrhythmia in patients with accessory atrioventricular pathways. Radio frequency ablation has become the curative treatment of first choice for th ese patients. Investigations after successful surgical pathway dissection r eported an almost complete elimination of paroxysmal atrial fibrillation. H owever, there are only a few reports which include a small number of patien ts undergoing radiofrequency ablation. The purpose of this study go was to examine whether successful radiofrequency ablation of accessory pathways pr events the occurrence of paroxysmal atrial fibrillation, and to identify po ssible predictors of atrial fibrillation recurrence. Methods and Results A total of 116 consecutive patients (mean age 42 +/- 15 years) with manifest or concealed accessory pathways and documented paroxy smal atrial fibrillation underwent radiofrequency catheter ablation. The pa tients were reexamined at 6 and 12 months. Long-term follow-up information was obtained by questionnaire and/or by consulting the referring physician. Pathway conduction was abolished in 101 cases (87%). Late follow-up inform ation was obtained from 91 of these 101 patients (90%) with successful abla tion with a mean follow-up duration of 23.9 +/- 12.3 months. During follow- up, 25 of 91 patients (27%) experienced arrhythmias. Recurrent episodes of atrial fibrillation were observed in 18 of these 25 cases (i.e. 20% of the 91 patients). Differences between patients with and without recurrences of atrial fibrillation were examined for age, sex: associated cardiac disease, presence of multiple pathways, pathway location? atrial fibrillation induc ibility during the procedure and cycle length of the atrioventricular reent rant tachycardia. Only older age was a significant independent predictor of atrial fibrillation recurrence (P=0.02). Eleven of 31 patients (35%) older than 50 years of age had atrial fibrillation recurrences during follow-up compared to seven of 60 patients (12%) under age 50. The recurrence rate of atrial fibrillation was even higher in patients older than 60 years (6 of 11 patients, i.e. 55%). In comparison, the occurrence rate of atrial fibril lation during follow-up in a control group of 100 consecutive patients with successful accessory pathway ablation, who did not have evidence of paroxy smal atrial fibrillation prior to ablation, was 4% and, thus, significantly lower than in the study group of the 91 patients (P=0.001). Conclusions The recurrence rate of paroxysmal atrial fibrillation after suc cessful radiofrequency ablation of accessory pathways shows an age-related increase, being low in patients younger than 50 years of age (12%) and high in the older patients: 35% in patients older than 50 years and 55% in pati ents older than 60. These results have significant therapeutic implications concerning the decisions on pharmacological therapy after successful ablat ion in patients older than 50 years. Furthermore, these data will help phys icians advise older patients properly about their risk of recurrence of atr ial fibrillation after ablation. (Eur Heart J 2001; 22: 423-27, doi:10.1053 /euhj.2000,2429) (C) 2001 The European Society of Cardiology.