Challenges Associated with Interpreting Mechanisms of AF

Abstract

Determining optimal treatment strategies for complex arrhythmogenesis in AF is confounded by the lack of consensus regarding the mechanisms causing AF. Studies report different mechanisms for AF, ranging from hierarchical drivers to anarchical multiple activation wavelets. Differences in the assessment of AF mechanisms are likely due to AF being recorded across diverse models using different investigational tools, spatial scales and clinical populations. The authors review different AF mechanisms, including anatomical and functional re-entry, hierarchical drivers and anarchical multiple wavelets. They then describe different cardiac mapping techniques and analysis tools, including activation mapping, phase mapping and fibrosis identification. They explain and review different data challenges, including differences between recording devices in spatial and temporal resolutions, spatial coverage and recording surface, and report clinical outcomes using different data modalities. They suggest future research directions for investigating the mechanisms underlying human AF.

Keywords: AF; anarchical multiple wavelets; anatomical re-entry; cardiac arrhythmia mechanisms; functional re-entry; hierarchical drivers; triggered activity.

Figure 1:. Mechanisms of AF

Figure 2:. Re-entry, Leading Circle and Spiral Mechanisms

Figure 3:. Phase Singularities May Occur at Lines of Conduction Block

Figure 5:. Type of Fibrotic Remodelling Affects Phase Singularity Locations, Where Anchors Could be Anatomical or Functional

Figure 4:. Pseudo Re-entrant Circuits Composed of Multiple Wavefronts May Appear as Stable Rotational Activity