Background: Many studies have reported a gradual increase in the arrhythmia recurrence in patients who underwent atrial fibrillation catheter ablation (AFCA). Although some observational studies have demonstrated various predictors of AF recurrence after AFCA, it is unclear which factors can predict late recurrence of successful AF ablation. The aim of this study was to produce a useful score for prediction of very late recurrence (>12 months) after first AFCA.
Methods: Study1: we retrospectively studied 112 consecutive patients (age 65 ± 8 years, male : 64 %, paroxysmal AF: 67 %) who were atrial tachyarrhythmia free > 12 months after first AFCA (2011-2013). We examined various echocardioghic parameters, 24-hour holter ECG (minimum coupling interval (CI) of atrial premature contraction (APC)) and serum markers and produce a novel score using the parameters which showed significant correlation with very late recurrence. Study 2: We elucidate whether the novel socre can predict very late recurrence in 2014 AFCA cohort which is comparable with study 1 cohort (age 65 ± 11 years, male: 70 %, paroxysmal AF: 78 %). .
Results: Study 1: very late AF recurrence was observed in twenty-four patients (21%) during follow up periods (mean follow up: 45±16 months). Female, early recurrence of AF (ERAF: recurrence within 3 months) and shorter minimum CI of APC (<49%, AUC: 0.72) obtained from 24-hour holter ECG at 12 months after AFCA were significantly associated with very late AF recurrence (p=0.01, p= 0.002 and p=0.02, respectively). Thus, we produce the FER2CI score (female: 1 point, ERAF: 2 points and CI<49%: 1 point) to predict very late recurrence. Study2: During follow-up period (27 ± 7 months), very late reccurence was found in 44 patiemts (--%). Higher FER2CI score (3 or 4) was significantly associated with long-term AF recurrence by Kaplan-Meier analysis (Log-rank test, p=0.03) (figure).
Conclusion: The FER2CI score is a useful novel score to predict very late recurrence after AFCA.