A Platform to guide Catheter Ablation of Persistent Atrial Fibrillation using Dominant Frequency Mapping

Abstract

Introduction: Dominant frequency (DF) analysis has been widely used to understand the pathophysiology of atrial fibrillation (AF). An interactive digital platform was developed to provide real-time DF mapping during DF-guided AF ablation. Methods: A user oriented graphic interface was developed in Matlab for real-time analysis of data exported from the non-contact balloon array (St. Jude Ensite Velocity System). The platform performs QRST subtraction on all electrograms (EGM) and Fast Fourier transform with 4 seconds windows (50% overlap) to compute DF, organization index (OI), regularity index (RI) and phase. DF, OI and RI of each window can be colour-coded and plotted on a 3D left atrium mesh, and 3D phase movies can also be played using a slider. High DF areas and the trajectory of their centres of gravity can be shown per individual window. Also any EGM of interest on the 3D mesh is easily accessible using the mouse. Results: 30 seconds of EGM data sampled at 2034.5 Hz with 2048 chan-nels are processed within 10 mins, which is acceptable for practical use dur-ing catheter ablation. The figure shows the percentage of processing time of each part of the program. Till now the software was tested and used success-fully in 5 catheter ablation cases. Conclusion: The proposed platform is fully automated with user-oriented graphic interface that provides a 3 dimensional representation of the left atrium with the DF behaviour. This software might provide further online information to relate DF to remodelled atrial substrate.