Electroanatomic Voltage mapping and Conduction Heterogeneity
Left and right atrial geometries created using Ensite Precision were exported and fused with the AcQMap anatomies using fiducial points and a nearest neighbour approach to assign bipolar voltage amplitude to each site on the AcQMap chamber enabling comparison between sites according to identified activation patterns.
Activation time maps obtained using Supermap were exported and analysed offline. The local activation time difference (LAT) for a 5mm radius from every vertex of the anatomy was calculated for each map and the largest value taken for each point to generate a histogram. The median LAT difference (MAT) and the conduction heterogeneity index (CHI) (95th percentile - 5thpercentile/median) was calculated within regions shown to demonstrate stable high frequency activation patterns during AF as described previously(8) and the effect of extrastimulus pacing on the CHI calculated in these regions compared to the remainder of the chamber.