Localized Atrial Tachycardia and Dispersion Regions in Atrial Fibrillation: Evidence of Spatial Concordance

Abstract

Introduction: During atrial fibrillation (AF) ablation, it is generally considered that atrial tachycardia (AT) episodes are a consequence of ablation. Objective: To investigate the spatial relationship between localized AT episodes and dispersion/ablation regions during persistent AF ablation procedures. Methods: We analyzed 72 consecutive patients who presented for an index persistent AF ablation procedure guided by the presence of spatiotemporal dispersion of multipolar electrograms. We characterized spontaneous or post-ablation ATs’ mechanism and location in regard to dispersion regions and ablation lesions. Results: In 72 consecutive patients admitted for persistent AF ablation, 128 ATs occurred in 62 patients (1.9 ± 1.1/patient). Seventeen ATs were recorded before any ablation. In a total of 100 ATs with elucidated mechanism, there were 58 localized sources and 42 macro-reentries. A large number of localized ATs arose from regions exhibiting dispersion during AF (n = 49, 84%). Importantly, these ATs’ locations were generally remote from the closest ablation lesion (n = 42, 72%). Conclusions: In patients undergoing a persistent AF ablation procedure guided by the presence of spatiotemporal dispersion of multipolar electrograms, localized ATs originate within dispersion regions but remotely from the closest ablation lesion. These results suggest that ATs represent a stabilized manifestation of co-existing AF drivers rather than ablation-induced arrhythmias.

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

“…Spatial concordance was recently shown using spatiotemporal EGM dispersion between AT locations and AF driver sites. 19 Previously, Baykaner et al 2 using basket recordings, and Yamashita et al 3 using electrographic imaging (ECGI), showed that AT in patients with AF arose at sites that also had harboured ablation termination sites for AF. Our study further advances this concept by revealing how AT-like regions in AF may affect AF treatment response.…”

Two decades of SVT ablation in Denmark: a trend towards higher age, more comorbidity, and less prior use of antiarrhythmic and rate-limiting pharmacotherapy—a nationwide registry-based Danish study

“…It cannot be ruled out that misclassification of atrial fibrillation and EAT in the clinic affects these results; however, previous studies have also shown a close association between atrial fibrillation and EAT. [ 16 , 17 ] A possible explanation for the increasing age could be that younger patients compared to older patients tend to opt out CA due to the risk of severe complications as AV blockage and need for pacemaker after the procedure. However, our results reenforces the encouraging trend that ablation in clinical practice is considered an effective treatment regardless of age and comorbidity.…”