Abstract 17291: Fractionated Atrial Electrograms Recorded During Sinus Rhythm: Is There a Difference Between Patients with Atrial Fibrillation and Controls?
Introduction: Ablation of atrial fibrillation (AF) may require adjunctive substrate modification. Recently, fractionated atrial electrograms recorded during sinus rhythm (SRF) have been suggested as an ablation target and termed “AF Nests”. However the occurrence of SRF in subjects without AF has not been clearly elucidated. Our aim was to determine the prevalence and the distribution of SRF in the left atrium (LA) of patients with and without a history of AF.
Methods: Twenty patients (age 62±9 yrs, 4 male) with a history of AF (20% paroxysmal), and 8 control subjects without structural heart disease or AF (age 36±6 yrs, 4 male) underwent detailed bipolar left atrial (LA) maps in SR (298±139 points). SRF maps were created off-line by classifying each point based on the number of deflections present in each electrogram. The percentage of SRF was calculated in each of 9 predefined regions of the LA (septum, anterior wall, roof, lateral, posterior, mitral annulus, appendage and pulmonary veins).
Results: SRF in patients with and without AF comprised 29±14% and 32±20% of the LA surface area, respectively (P=NS). SRF was most prevalent on the LA septum (53% and 71%), roof (34% and 31%), and anterior wall (45% vs. 54%), and least prevalent in the LA appendage (11% and 8%, Figure). There was no significant difference in the distribution of SRF between patients with AF and controls (p=0.74).
Conclusions: 1) There is no significant difference in the prevalence and distribution of fractionated electrograms recorded during sinus rhythm in patients with and without AF. 2) The most fragmented areas were the septal regions of the LA. 3) These observations suggest that fractionated electrograms recorded during sinus rhythm may not be a suitable ablation target.
- © 2010 by American Heart Association, Inc.