Short-time Fourier analysis of signal averaged electrocardiograms

Signal averaged electrocardiograms (SAEs) of subjects with and without late potentials were compared. using windows of 50- and 100-m widths, short-time Fourier analysis was performed on each electrocardiogram. Frequency ratios of the energy between 0 and 40 Hz and 40 and 120 Hz were computed for each time shift of the window for all SAEs. Those with late potentials (LPs) could be distinguished from those without LPs on the basis of the energy ratio computed using the 100-ms window.<
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