Entropy at the right atrium as a predictor of atrial fibrillation recurrence outcome after pulmonary vein ablation

[EN] Atrial fibrillation (AF) recurrence rates after successful ablation procedures are still high and difficult to predict. This work studies the capability of entropy measured from intracardiac recordings as an indicator for recurrence outcome. Intra-atrial recordings from 31 AF patients were registered previously to an ablation procedure. Four electrodes were located at the right atrium (RA) and four more at the left atrium (LA). Sample entropy measurements were applied to these signals, in order to characterize different non-linear AF dynamics at the RA and LA independently. In a 3 months follow-up, 19 of them remained in sinus rhythm, whereas the other 12 turned back to AF. Entropy values can be associated to a proarrhythmic indicator as they were higher in patients with AF recurrence (1.11 +/- 0.15 vs. 0.91 +/- 0.13), in persistent patients (1.03 +/- 0.19 vs. 0.96 +/- 0.15), and at the LA with respect to the RA (1.03 +/- 0.23 vs. 0.89 +/- 0.15 for paroxysmal AF patients). Furthermore, entropy values at the RA arose as a more reliable predictor for recurrence outcome than at the LA. Results suggest that high entropy values, especially at the RA, are associated with high risk of AF recurrence. These findings show the potential of the proposed method to predict recurrences post-ablation, providing additional insights to the understanding of arrhythmia.This work was supported by the Castilla-La Mancha Research Scheme (PPII- 2014-024-P).Cervigon, R.; Moreno, J.; Garcia-Quintanilla, J.; Perez-Villacastin, J.; Castells, F. (2016). Entropy at the right atrium as a predictor of atrial fibrillation recurrence outcome after pulmonary vein ablation. BIOMEDIZINISCHE TECHNIK. 61(1):29-36. https://doi.org/10.1515/bmt-2014-01722936611Nilsson, F., Stridh, M., Bollmann, A., & Sörnmo, L. (2006). Predicting spontaneous termination of atrial fibrillation using the surface ECG. Medical Engineering & Physics, 28(8), 802-808. doi:10.1016/j.medengphy.2005.11.010Petersson, R., Sandberg, F., Platonov, P. G., & Holmqvist, F. (2011). Noninvasive estimation of organization in atrial fibrillation as a predictor of sinus rhythm maintenance. Journal of Electrocardiology, 44(2), 171-175. doi:10.1016/j.jelectrocard.2010.10.033Pincus, S. (1995). Approximate entropy (ApEn) as a complexity measure. Chaos: An Interdisciplinary Journal of Nonlinear Science, 5(1), 110-117. doi:10.1063/1.166092Aliot, E., Breithardt, G., Brugada, J., Camm, J., Lip, G. Y. H., … Vardas, P. E. (2010). An international survey of physician and patient understanding, perception, and attitudes to atrial fibrillation and its contribution to cardiovascular disease morbidity and mortality. Europace, 12(5), 626-633. doi:10.1093/europace/euq109Schotten, U., Maesen, B., & Zeemering, S. (2012). The need for standardization of time- and frequency-domain analysis of body surface electrocardiograms for assessment of the atrial fibrillation substrate. Europace, 14(8), 1072-1075. doi:10.1093/europace/eus056Lo, L.-W., Tai, C.-T., Lin, Y.-J., Chang, S.-L., Udyavar, A. R., Hu, Y.-F., … Chen, S.-A. (2009). Predicting factors for atrial fibrillation acute termination during catheter ablation procedures: Implications for catheter ablation strategy and long-term outcome. Heart Rhythm, 6(3), 311-318. doi:10.1016/j.hrthm.2008.11.013Cervigón, R., Moreno, J., Reilly, R. B., Millet, J., Pérez-Villacastín, J., & Castells, F. (2010). Entropy measurements in paroxysmal and persistent atrial fibrillation. Physiological Measurement, 31(7), 1011-1020. doi:10.1088/0967-3334/31/7/010Botteron, G. W., & Smith, J. M. (1995). A technique for measurement of the extent of spatial organization of atrial activation during atrial fibrillation in the intact human heart. IEEE Transactions on Biomedical Engineering, 42(6), 579-586. doi:10.1109/10.38719