title: Cardiac electrical instability of the arrhythmogenic tissue substrate assessed by means of wavelet transform.
abstract: The unstable activation wavefront from the tissue responsible for the production of ventricular tachycardia (VT) gives rise to beat-variable signals components that are eluded during the averaging step of high resolution ECG (HRECG). We used a mathematical model of small variations in a largely repetitive waveform to evaluate the beat-to-beat variance of the HRECG signal. The ability of the Morlet Wavelet Transform to discriminate the different factors responsible for the beat-variability (the alignment error and the beat-variable signal component) has been assessed on simulated signals. The performance evaluation on real ECG signals from normal subjects and patients with a documented history of ventricular tachycardia showed that the dynamics of the arrhythmogenic substrate as revealed by wavelet transform offers a significant improvement in ventricular tachycardia risk assessment.
authors.affiliation: Dept. of Medical Physics, University of Patras, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Popescu
authors.forename: N
authors.initials: N
authors.lastname: Laskaris
authors.forename: A
authors.initials: A
authors.lastname: Merloi
authors.forename: I
authors.initials: I
authors.lastname: Chiladakis
authors.forename: C
authors.initials: C
authors.lastname: Stathopoulos
authors.forename: A
authors.initials: A
authors.lastname: Manolis
authors.forename: P
authors.initials: P
authors.lastname: Cristea
authors.forename: A
authors.initials: A
authors.lastname: Bezerianos
mesh_terms: D003198:Computer Simulation; D004562:Electrocardiography / Q000295:instrumentation*; D005583:Fourier Analysis; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008962:Models, Theoretical; D012016:Reference Values; D018570:Risk Assessment; D012815:Signal Processing, Computer-Assisted; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000503:physiopathology