Predictive value of entropy analysis for atrial fibrillation recurrence after ablation procedures

The aim of this work is to improve AF dynamics understanding through predicting the reversion to sinus rhythm in the procedures of ablation. Signals from intracardiac recordings previous to ablation were characterized using entropy measurements. The database includes intracardiac recordings from 22 AF patients submitted to an ablation procedure. Four electrodes were located at the right atrium (RA) and 4 more at the left atrium (LA). All patients were monitored after ablation, and were divided in 2 groups according to AF recurrence outcome: 11 of them remained in sinus rhythm, whereas the other 11 turned back to AF. Sample entropy was applied to these signals, in order to characterize different non-linear AF dynamics at RA and LA independently. Results showed statistical significant differences along the atria between both groups (p=0.031). When analyzing regional results, these differences were emphasized at the RA. However, non-statistically significant results were obtained at the LA. Moreover, regional differences were analyzed in both groups separately. In the recurrent group, nonstatistically significant differences between both atria were found, although in the non-recurrent group they were found, p=0.038. These findings show the potential of entropy measurements as useful predictors of AF recurrence after successful ablation of AF.