Identifying (electrophysiological) predictors of atrial fibrillation recurrences after catheter ablation: first results from the ISOLATION registry

Abstract

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): a.o. The European Union (ITN Network Personalize AF: Personalized Therapies for Atrial Fibrillation: a translational network, grant number 860974; MAESTRIA: Machine Learning Artificial Intelligence Early Detection Stroke Atrial Fibrillation, grant number 965286). Background/Introduction Noninvasive quantification of electrophysiological properties of the atria is increasingly used for outcome prediction in atrial fibrillation (AF) patients. Data on the added value of ECG parameters to predict AF recurrences in patients undergoing AF ablation are scarce. Purpose To investigate the predictive performance of clinical and echocardiographic characteristics as well as features extracted from extended surface electrocardiogram (extECG) recordings for AF recurrences in patients after AF ablation. Methods ISOLATION is a prospective, observational, multicenter registry of patients scheduled for AF catheter ablation, including cryoballoon and radiofrequency ablation. 178 patients (66.4%) patients used anti arrhythmic drugs at baseline. Clinical characteristics and results of routine blood tests were collected. In addition, an extECG was recorded (12 additional leads, 5 minutes recording) before ablation to analyze P-wave characteristics. The main study endpoint was ablation success after 12 months, defined as freedom from any episode of documented atrial arrhythmia after the blanking period recorded on holter or ECG. Results Currently, 627 of 650 scheduled patients have been included. In total, 268 patients completed the 1-year follow-up. 190 patients (70.9%) had paroxysmal AF and 75 patients (28.0%) had persistent AF. Median age was 65±9 years, 38.1% were female. 46 patients (17.2%) had a recurrence of AF after 12 months [figure 1]. Univariate analysis showed that higher age (64 years vs. 69 years, p=0.023, Mann-Whitney U-test), lower P-wave mean area (4.402 mV vs. 3.567 mV, p=0.034) and lower P-wave mean amplitude (0.087 mV vs. 0.081 mV, p=0.033), were associated with a higher recurrence rate of AF [figure 2]. However, multivariate analysis showed no significant independent prognostic factors so far. Conclusion Our first results show that patients with AF recurrences after catheter ablation are older, show lower P-wave mean area and lower P-wave mean amplitude. We need to wait for the completion of follow-up in more patients, before we can determine the predictive value of P-wave parameters derived from extECGs for the prediction of AF recurrence and to identify predictive factors with more subtle effects on risk for AF recurrences.