Abstract 10109: Left Atrial Wall Thickness Rather Than Epicardial Fat Related With the Complex Fractionated Atrial Electrogram
Background: The mechanism of complex fractionated atrial electrogram (CFAE) in patients with atrial fibrillation (AF) remains controversial. This study investigated the relationship between CFAE, the left atrial wall thickness (LAWT) and epicardial fat thickness (EFT).
Methods: Thirty three patients (27 men, 56.9 ± 9.0 years) with symptomatic paroxysmal (n = 13) or persistent (n = 20) AF were studied. Atrial electrograms during AF were mapped/analyzed using an automated CFAE algorithm. Using multi detector computed tomography, we measured LAWT and EFT in a total of 31 sites including 9 anterior, 3 roof, 9 posterior, 3 bottom, 1 anterior appendage base, 3 lateral, and 3 septal sites in each patient.
Results: Mean LA size was 45.0 ± 5.0 mm and left ventricular ejection fraction was 64.0 ± 7.1%. There was a large range of LAWT (median: 1.75mm, range 0.57-5.65 mm) and EFT (median: 3.11mm, range 0.00-22.50 mm). In addition, there were significant regional differences in LAWT and EFT. The septal area had the thickest LAWT (2.36 ± 0.78 mm) and the posterior wall was thinnest (1.65 ± 0.32 mm). The bottom area had the thickest EFT (9.62 ± 3.91 mm) and the anterior wall was thinnest EFT (1.26 ± 0.68 mm).
Each patient had average 7.6 (24.5%) CFAE sites among 31 sites. In a total of 1023 sites, LA wall was much thicker at the areas with CFAE than those without CFAE (2.25 ± 0.72 vs. 1.75 ± 0.54 mm, p<0.001). However, EFT showed no difference between the areas with and without CFAE (3.66 ± 3.70 vs. 4.17 ± 4.17 mm, p=0.093).
In 15 patients, CFAE mapping was performed before and after PV isolation (PVI) and the CFAE in thicker LA was disappeared after PVI compared to those in thinner LA (2.32 ± 0.60 vs. 1.82 ± 0.56 mm, p<0.001). And CFAE area was decreased after PVI (21.25 ± 19.33 vs. 4.61 ± 5.05 cm2, p=0.002).
Conclusion: The LAWT and CFAE area were well correlated, suggesting that the mechanism of CFAE was related with LAWT. The CFAE in thicker LA area was disappeared after PVI.
- © 2013 by American Heart Association, Inc.