Quantifying a spectrum of clinical response in atrial tachyarrhythmias using spatiotemporal synchronization of electrograms

Abstract

Aims There is a clinical spectrum for atrial tachyarrhythmias wherein most patients with atrial tachycardia (AT) and some with atrial fibrillation (AF) respond to ablation, while others do not. It is undefined if this clinical spectrum has pathophysiological signatures. This study aims to test the hypothesis that the size of spatial regions showing repetitive synchronized electrogram (EGM) shapes over time reveals a spectrum from AT, to AF patients who respond acutely to ablation, to AF patients without acute response. Methods and results We studied n = 160 patients (35% women, 65.0 ± 10.4 years) of whom (i) n = 75 had AF terminated by ablation propensity matched to (ii) n = 75 without AF termination and (iii) n = 10 with AT. All patients had mapping by 64-pole baskets to identify areas of repetitive activity (REACT) to correlate unipolar EGMs in shape over time. Synchronized regions (REACT) were largest in AT, smaller in AF termination, and smallest in non-termination cohorts (0.63 ± 0.15, 0.37 ± 0.22, and 0.22 ± 0.18, P < 0.001). Area under the curve for predicting AF termination in hold-out cohorts was 0.72 ± 0.03. Simulations showed that lower REACT represented greater variability in clinical EGM timing and shape. Unsupervised machine learning of REACT and extensive (50) clinical variables yielded four clusters of increasing risk for AF termination (P < 0.01, χ2), which were more predictive than clinical profiles alone (P < 0.001). Conclusion The area of synchronized EGMs within the atrium reveals a spectrum of clinical response in atrial tachyarrhythmias. These fundamental EGM properties, which do not reflect any predetermined mechanism or mapping technology, predict outcome and offer a platform to compare mapping tools and mechanisms between AF patient groups.

What is atrial fibrillation? A RETRO-spective analysis

“…The authors are to be commended for providing a potential solution for processing electrophysiological activation data of AF with the potential to include this information into the ablation procedure. Furthermore, the data of this study reinforce the paradigm that AF perpetuation follows an organized and repetitive activation pattern (10).…”

What is atrial fibrillation? A RETRO‐spective analysis

“…The authors are to be commended for providing a potential solution for processing electrophysiological activation data of AF with the capability to include this information in the ablation procedure. Furthermore, the data of this study reinforce the paradigm that AF perpetuation follows an organized and repetitive activation pattern 10 …”

Vector Field Heterogeneity for the Assessment of Locally Disorganised Cardiac Electrical Propagation Wavefronts From High-Density Multielectrodes

“…Furthermore, major works have been recently proposed to understand and characterise the organisation of wavefront propagation based on intracardiac recordings. In particular, the study by Ganesan et al [40] defines a novel metric coined as REACT to evaluate the size of the areas containing synchronised EGMs, shown to be predictive of ablation outcomes. Shortly afterwards, a similar analysis proposes Repetitive Atrial Activation Patterns (RAAPs), found to be associated with arrhythmia drivers [41] .…”