Abstract
Traditional anatomically guided ablation and attempts to perform electrogram-guided atrial fibrillation (AF) ablation (CFAE, DF, and FIRM) have not been shown to be sufficient treatment for persistent AF. Using biatrial high-density electrophysiologic mapping in a canine rapid atrial pacing model of AF, we systematically investigated the relationship of electrogram morphology recurrence (EMR) (Rec% and CLR) with established AF electrogram parameters and tissue characteristics. Rec% correlates with stability of rotational activity and with the spatial distribution of parasympathetic nerve fibers. These results have indicated that EMR may therefore be a viable therapeutic target in persistent AF.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 68-84 |
| Number of pages | 17 |
| Journal | JACC: Basic to Translational Science |
| Volume | 8 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 2023 |
Funding
In the present study, we discovered that discrete morphology patterns exist in AF and can be identified with the novel morphology recurrence plots. Rec% and CLR are only somewhat correlated with established EGM measures of AF fractionation (FI) and complexity (ShEn), and provide new information in quantifying the degree of repeatability of EGM morphologies. We therefore think that these new measures provide more information about the nature of arrhythmogenic AF substrate than more traditional EGM measures for detecting AF sources. To test this hypothesis, we performed a systematic analysis of the number, stability, and cycle length of 360-degree rotational activity in different regions of the atria. Previous studies have found a strong relationship between the presence and number of these rotational activities and the ability of the atria to sustain AF.60 In the present study, the stability of rotational activities in different subregions of the atria was found to correlate with Rec%, helping to serve as an important initial validation of our postulate that sites of high recurrence morphology with the shortest cycle lengths—ie, regions of low CLR—may represent sites of AF drivers. Interestingly though, even this correlation between Rec% and stability of rotational activity is moderate at best, suggesting that EGM morphology recurrence is influenced by other factors as well (and is perhaps a better indicator of arrhythmogenic substrate than rotational activity alone). Indeed, our results show that while no one AF EGM measure correlates with all of the measures of AF substrate that were systematically examined—myofiber orientation, fibrosis, and autonomic innervation—Rec% and CLR do reflect arrhythmogenic substrate (especially parasympathetic innervation) better than all previously AF EGM measures. Taken together, we think that EGM morphology recurrence may be a better marker of arrhythmogenic substrate in the atria than traditional measures of AF organization/fractionation as well as measures of rotational activity that rely on frequency characteristics of AF signals. These data support further testing of this hypothesis in large-animal models or human patients with persistent AF by performing targeted ablation at sites of low CLR.
Keywords
- arrhythmias
- atrial fibrillation
- fibrosis
- mapping
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine