Table of Contents

Introductory slide

Objectives and Methods

VF initiated by 50 Hz stimulation (10 s of VF signal in time domain)

VF initiated by 50 Hz stimulation (initial and end intervals - time and frequency domain; same patient)

VF initiated by T-shock (10 s of VF signal in time domain; same patient)

VF initiated by T-shock stimulation (initial and end intervals - time and frequency domain; same patient)

Short-time spectra were estimated using Auto-Regressive (AR) modeling of short time VF epochs of optimum length

AR power spectrum estimation - main equation

Spectral Distance estimation - main equation

Early spectrum: 50 Hz vs. TS type of VF (same patient)

Late spectrum: 50 Hz vs. TS type of VF (same patient)

Spectral Distance between the two VF types (same patient)

Spectral Distance between the two VF types (all patients)

Dynamics of VF Spectral Distance of overlapping short intervals in the middle interval Tm with respect to late VF

Dynamics of the 50 Hz type of VF. Time course of the spectral distance illustrating the way VF-50Hz parameters evolve in time. For all patients the distances between subsequent time segments in Tm and late VF (Te) were calculated and plotted.

Dynamics of the TS type of VF. Time course of the spectral distance illustrating the way VF-TS parameters evolve in time. For all patients the distances between subsequent time segments in Tm and late VF (Te) were calculated and plotted.

VF dynamics: Time course of the spectral distance, averaged for all patients. The standard deviation for each VF type is shown.

Conclusions