Patterns in Hilbert transforms and Wigner-Ville distributions of electrocardiogram data

The computation and characteristics of two new representations of single lead electrocardiogram data, both based upon the analytic signal corresponding to the waveform, are presented. The first method, employing a complex plane plot of the analytic signal, emphasizes waveform shape independently of time base; the second, a time-frequency representation using the Wigner-Ville distribution, appears to highlight instantaneous frequency variation within the waveform. Both are potentially useful when the patterns are displayed using contour plots, and a specific computerised pattern recognition technique is suggested and some results presented.