Wavelet analysis of spatial dispersion of P-wave morphology in patients converted from atrial fibrillation

Identifying patients at risk for atrial fibrillation (AF) is a major task of noninvasive electrophysiology. In this study, we aimed to evaluate the usefulness of a wavelet transformation method describing spatial dispersion of time-frequency components of P-waves for identifying patients at risk for AF. We recorded the X, Y, Z-lead high-resolution ECGs in 18 patients with AF converted to sinus rhythm and 29 healthy control subjects. In each lead, a 256-ms segment encompassing the P wave was decomposed into a network of 255 time-frequency cells. In a median beat from 10 consecutive beats, spatial (interlead) heterogeneity of time-frequency components of the P-wave was quantified. Time-frequency cells and combinations of cells were analyzed for significance of separating AF from healthy subjects. Two parameters describing low frequency components (LFC), and high frequency components (HFC) of P-waves were designed. The wavelet-based method demonstrated increased heterogeneity of P-wave in patients converted from atrial fibrillation. Our preliminary results indicate that analysis of spatial heterogeneity of P-wave morphology may he useful in identifying patients at risk for atrial fibrillation