Analysis of P-wave Changes for Prediction of Atrial Fibrillation Episodes

The aim of this study is to assess the value of P-wave morphology markers in sinus rhythm to predict the imminence of atrial fibrillation (AF) episodes in patients with paroxysmal AF (PxAF). P-wave signal-to-noise ratio (SNR) is emphasized by signal processing methods based on principal component (PCA) and periodic component (πCA), together with time averaging analysis. The P-wave morphology features considered are: total power, relative power components, power at high frequency bands (as a measure of rugosity) and P-wave duration. Features are evaluated at three different five-minute time intervals before AF episode occurrences (at 5 minutes, 30 minutes and 60 minutes before the episode onset) in PxAF patients. Results show that in PxAF patients the relative power of the second-to-first principal component increases and the mean duration of the first principal and periodic P-wave component also increases when the time interval gets closer to the AF episode onset. No significant differences were observed in P-wave rugosity by none of both methods. These findings can be interpreted as P wave becoming more complex and wider at the imminence of AF episodes.