Regional conduction velocity calculation from clinical multichannel electrograms in human atria

摘要

Abstract Background During atrial fibrillation, heterogeneities and anisotropies result in a chaotic propagation of the depolarization wavefront. The electrophysiological parameter called conduction velocity (CV) influences the propagation pattern over the atrium. We present a method that determines the regional CV for deformed catheter shapes, which result due to the catheter movement and changing wall contact. Methods The algorithm selects stable catheter positions, finds the local activation times (LAT), considers the wall contact and calculates all CV estimates within the area covered by the catheter. The method is evaluated with simulated data and then applied to four clinical data sets. Both sinus rhythm activity as well as depolarization wavefronts initiated by stimulation are analyzed. The regional CV is compared with the fractionation duration (FD) and peak-to-peak (P2P) voltages. A speed of 0.5?m/s was defined to create the simulated LAT. Results After analyzing the simulated LAT with clinical catheter spatial coordinates, the median CV of 0.5?m/s with an interquartile range of 0.22 and exact CV direction vectors were obtained. For clinical cases, the CV magnitude range of 0.08?m/s to 1.0?m/s was obtained. The P2P amplitude of 0.7?mV to 3.7?mV and the mean FD from 40.79ms to 48.66ms was obtained. The correlation of 0.86 was observed between CV and P2P amplitude, and 0.62 between CV and FD. Conclusion In this paper, a method is presented and validated which calculates the CV for the deformed catheter and changing wall contact. In an exemplary clinical data set correlation between regional CV with FD and the P2P voltage was observed. Highlights ? Regional CV calculated for stable catheter positions and individual cardiac excitation. ? The algorithm works for different catheter shapes and changing wall contact. ? The algorithm has been benchmarked with simulated data. ? A novel method to identify critical, slow conducting substrate.