Distinctive patterns of dominant frequency trajectory behavior in drug-refractory persistent atrial fibrillation: preliminary characterization of spatiotemporal instability.

João L Salinet,Jiun H Tuan,G André Ng,Peter J Stafford,Alistair J Sandilands,Fernando S Schlindwein

doi:10.1111/jce.12331

Abstract

The role of substrates in the maintenance of persistent atrial fibrillation (persAF) remains poorly understood. The use of dominant frequency (DF) mapping to guide catheter ablation has been proposed as a potential strategy, but the characteristics of high DF sites have not been extensively studied. This study aimed to assess the DF spatiotemporal stability using high density noncontact mapping (NCM) in persAF. Eight persAF patients were studied using NCM during AF. Ventricular far-field cancellation was performed followed by the calculation of DF using Fast Fourier Transform. Analysis of DF stability and spatiotemporal behavior were investigated including characteristics of the highest DF areas (HDFAs). A total of 16,384 virtual electrograms (VEGMs) and 232 sequential high density 3-dimensional DF maps were analyzed. The percentage of DF stable points decreased rapidly over time. Repetition or reappearance of DF values were noted in some instances, occurring within 10 seconds in most cases. Tracking the HDFAs' center of gravity revealed 3 types of propagation behavior, namely (i) local, (ii) cyclical, and (iii) chaotic activity, with the former 2 patterns accounting for most of the observed events. DF of individual VEGMs was temporally unstable, although reappearance of DF values occurred at times. Hence, targeting sites of 'peak DF' from a single time frame is unlikely to be a reliable ablation strategy. There appears to be a predominance of local and cyclical activity of HDFAs hinting a potentially nonrandom temporally periodic behavior that provides further mechanistic insights into the maintenance of persAF.

Highlights

The role of substrates in the maintenance of persistent atrial fibrillation remains poorly understood
Spectral analysis has been used for the analysis of AF electrograms (EGMs) to identify areas within the atria that contain high dominant frequency (DF) signals which may be responsible for driving the rhythm.[3]
Using non-contact mapping (NCM) analysis of individual virtual AF electrograms (VEGM), we have demonstrated that DF is not temporally stable during persistent atrial fibrillation (persAF), reappearance of DF values can occur at times

Summary

Introduction

The role of substrates in the maintenance of persistent atrial fibrillation (persAF) remains poorly understood. This study aimed to assess the DF spatiotemporal stability using high density non-contact mapping (NCM) in persAF. Spectral analysis has been used for the analysis of AF electrograms (EGMs) to identify areas within the atria that contain high dominant frequency (DF) signals which may be responsible for driving the rhythm.[3] It has been suggested that ablation at these sites could be an effective way to terminate AF.[4] In addition, ablation strategies which include pulmonary vein (PV) isolation and additional linear lesions have been shown to reduce local and/or global DF with an associated beneficial post-ablation outcome, highlighting DF as an important parameter.[5,6,7] DF mapping during AF has been performed largely using point-bypoint sequential mapping. The aim of this study was to characterise the spatiotemporal behaviour of DF during AF using NCM in patients with persAF to help further the understanding of the significance and utility of DF mapping

Objectives

Methods

Results

Discussion

Conclusion