Distribution of atrial electrogram types during atrial fibrillation: Effect of rapid atrial pacing and intercaval junction ablation

  • Li H
  • Hare J
  • Mughal K
 et al. 
  • 3

    Readers

    Mendeley users who have this article in their library.
  • 46

    Citations

    Citations of this article.

Abstract

Objectives. This study examined the anatomic distribution types and possible determinant of atrial electrogram types during atrial fibrillation. Background. Different types of atrial electrograms during atrial fibrillation have been observed and classified, but their anatomic distribution patterns, determinants and potential usefulness in guiding future catheter ablation are unknown. Methods. Two animal models of atrial fibrillation were used: the sterile pericarditis model (n = 10) and the rapid atrial pacing model (400 beats/min for 6 weeks, n = 6). The atrial electrogram of atrial fibrillation and the atrial effective refractory period were obtained from multiple sites of the right and left atrium. In addition, decremental rapid atrial stimulation was applied to the site of shortest and longest atrial effective refractory periods until atrial fibrillation induction in a subgroup of nine dogs. Ablation of the intercaval junction was performed using the radiofrequency catheter technique in dogs with atrial fibrillation duration >1 min. Results. In both models, organized atrial electrograms (type I) were predominantly observed at the left atrial sites and the right atrial appendage, whereas disorganized atrial electrograms (type III) were mainly observed at the right posterolateral atrium. The distribution of the atrial electrogram types closely followed that of the atrial effective refractory period, with the shortest atrial effective refractory period corresponding to organized atrial electrograms (type I) and the longest atrial effective refractory period corresponding to disorganized atrial electrograms (type III). The correlation of atrial electrogram type with the atrial effective refractory period was further demonstrated by the effect of rapid atrial stimulation. When rapid atrial stimulation was applied to the site with the shortest atrial effective refractory period, disorganized atrial electrograms were observed at sites with the longest atrial effective refractory period, whereas 1:1 atrial capture was still present at the stimulation site. Ablation of the intercaval junction made atrial fibrillation noninducible or tended to shorten the atrial fibrillation duration (from 26.4 ± 24.2 to 8.8 ± 22.6 min in the pericarditis group, p = 0.02, and from 33.7 ± 29.2 to 12.1 ± 23.8 min in the rapid pacing group, p = 0.09) but did not change the atrial electrogram types during atrial fibrillation. Conclusions. Various types of atrial electrograms are present at different locations during atrial fibrillation. The atrial electrogram characteristics of atrial fibrillation at a specific location are related to the atrial effective refractory period, with short effective refractory periods associated with organized atrial electrograms and long effective refractory periods associated with disorganized electrograms.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Huagui Li

  • John Hare

  • Kashef Mughal

  • David Krum

  • Michael Biehl

  • Sanjay Deshpande

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free