Related Experiment Video
Updated: May 10, 2025
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
The atrial electrocardiogram in patients with persistent atrial fibrillation
Ghaith Zaatari1, Jorge Bohorquez2, Laura E Sutaria3
1Division of Cardiology, Department of Medicine, University of Miami, Miami, Florida.
Background:
The electrocardiogram (ECG) in persistent atrial fibrillation (AF) is underused. Signal processing techniques can extract the f-waves from the QRS-T complex to generate the atrial ECG (A-ECG).
Objective:
This study aimed to explore A-ECG technical and clinical issues.
Methods:
Thirty patients (age, 62.6 ± 9.4 years; 80% male; CHA2DS2-VASc score, 2.2 ± 1.7; ejection fraction, 47.9% ± 10.4%) with persistent AF undergoing ablation were enrolled. ECGs were downloaded for offline analysis. A-ECG was derived by QRS-T subtraction and independent component analysis filtering. A-ECG short-term (DF10s, OI10s) and long-term (DF_Global, OI_Global) spectral features were derived. Optimal recording duration, temporal reproducibility, differences between leads, comparison to intracardiac dominant frequency (DF), acute ablation effect, and A-ECG differences based on ablation outcomes were evaluated.
Results:
Time-frequency A-ECG analysis demonstrated dynamic spectral features. Repeated 10-second A-ECG recordings had higher coefficient of variation (7.5%-10.0%) compared with repeated 4- to 5-minute recordings (1.1%-3.4%). Short-term reproducibility of 2 recordings ∼30 minutes apart showed high correlation (r = 0.91-0.99; all P values < .0001). Regional lead analyses showed no significant differences except for the comparison of posterior leads V7-V9 vs V1-V3. A-ECG DF parameters correlated with right atrial DF (r = 0.64-0.72; P < .0001) and not left atrial DF. A-ECG DF declined after ablation (median-DF10s-1min, 5.94 ± 0.63 Hz vs 5.77 ± 0.63 Hz; P = .0003). Patients with successful ablation at 1 year had higher A-ECG DF vs those with recurrences (median-DF10s-5min, 6.04 ± 0.42 Hz vs 5.13 ± 0.93 Hz; P = .003).
Conclusion:
This study provides the practical basis for further use of the A-ECG as a novel tool for evaluating persistent AF and demonstrates its clinical relevance. Further phenotypic classification of AF based on the A-ECG and assessment of treatment response should be explored.
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