Relationship between the CHADS2 score and risk of very late recurrences after catheter ablation of paroxysmal atrial fibrillation

BACKGROUND Catheter ablation of paroxysmal atrial fibrillation has been performed for more than 10 years. However, data about the long-term results were limited. OBJECTIVES To evaluate the long-tem efficacy following paroxysmal atrial fibrillation ablation and to investigate whether there were different patterns of recurrences in patients with different CHADS(2) scores. METHODS A total of 238 patients with paroxysmal atrial fibrillation who received a catheter ablation from 2004 to 2007 were enrolled. Free of recurrence was defined as the absence of atrial arrhythmias without using any antiarrhythmic agents after ablation. RESULTS There were 121 patients (50.8%) suffering from recurrences after the first ablation procedure during a median follow-up period of 5 years. The CHADS(2) score and left atrial diameter were significant predictors of recurrences in the multivariate analysis. Different patterns of recurrence were observed in different groups of patients categorized on the base of CHADS(2) score. Among patients with a CHADS(2) score of >= 3 without recurrences at 2 years postablation, 63.6% experienced episodes of arrhythmias during the subsequent follow-up period. In contrast, in patients with a CHADS(2) score of 0 without recurrences at 2 years postablation, the future recurrence rate was only 2.7%. CONCLUSIONS After a successful ablation, recurrences may continue to occur without reaching a plateau during the long-term follow-up, especially in patients with a high CHADS(2) score. The optimal follow-up strategy may differ and should be individualized for patients with different scores.