Introduction: Patients who undergo pulmonary vein isolation for atrial fibrillation can develop recurrent atrial fibrillation (AF) and/or atrial tachycardia (AT). We hypothesized that analyzing AF and AT surface waves on electrocardiograms using spectral analysis techniques would offer insights into the differences between post-ablation AF versus AT.
Methods: We performed a retrospective study of 70 patients who had undergone pulmonary vein isolation and returned for a second ablation due to recurrent AF or AT. Surface electrocardiograms were analyzed using waveform spectral analysis to calculate the following atrial parameters: dominant frequency, dominant amplitude (the amplitude of the dominant frequency), and mean spectral profile (average amplitude of the normalized spectrum) and standard deviation.
Results: Surface electrocardiogram analyses revealed that AF patients manifested the following features when compared to AT patients: higher dominant frequencies (5.80 vs. 4.30 Hz, p?0.0001), lower dominant amplitudes (2.44 vs. 3.68, p<0.0001), higher mean spectral profiles (0.31 vs. 0.19, p<0.0001), and higher standard deviations of mean spectral profiles (0.173 vs. 0.156, p=0.0015).
Conclusions: Non-invasive, electrocardiogram-based signal analyses can be used to measure the degree of differences between atrial frequency as well as spectral organization in patients with AF vs. AT. Further analyses are required to assess whether these techniques can help to differentiate among various types of post-ablation ATs.