title: A simulation of T-wave alternans vectocardiographic representation performed by changing the ventricular heart cells action potential duration.
abstract: The presence of T wave alternans (TWA) in the surface ECG signals has been recognized as a marker of electrical instability, and is hypothesized to be related to patients at increased risk for ventricular arrhythmias. In this paper we present a TWA simulation study. The TWA phenomenon was simulated by changing the duration of the ventricular heart cells action potential. The magnitude was calculated in the surface ECG with the use of the time domain method. The spatially concordant TWA, where during one heart beat all ventricular cells display a short-duration action potential and during the next beat they exhibit a long-duration action potential, as well as the discordant TWA, where at least one region is out of phase, was simulated. The vectocardiographic representation was employed. The obtained results showed a high level of T-loop pattern and location disturbances connected to the discordant TWA simulation in contrast to the concordant one. This result may be explained by the spatial heterogeneity of the ventricular repolarization process, which could be higher for the discordant TWA than for the concordant TWA.
authors.affiliation: Department for Biophysical Measurements and Imaging, Nalecz Institute of Biocybernetic and Biomedical Engineering PAS, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland. Electronic address: djanusek@ibib.waw.pl.
authors.forename: D
authors.initials: D
authors.lastname: Janusek
authors.affiliation: Department for Biophysical Measurements and Imaging, Nalecz Institute of Biocybernetic and Biomedical Engineering PAS, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Kania
authors.affiliation: First Department of Cardiology, Medical University of Warsaw, 1A Banacha Str., 02-097 Warsaw, Poland.
authors.forename: R
authors.initials: R
authors.lastname: Zaczek
authors.affiliation: Department for Biophysical Measurements and Imaging, Nalecz Institute of Biocybernetic and Biomedical Engineering PAS, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland.
authors.forename: H
authors.initials: H
authors.lastname: Zavala-Fernandez
authors.affiliation: Department for Biophysical Measurements and Imaging, Nalecz Institute of Biocybernetic and Biomedical Engineering PAS, 4 Ks. Trojdena Str., 02-109 Warsaw, Poland.
authors.forename: R
authors.initials: R
authors.lastname: Maniewski
mesh_terms: D000200:Action Potentials; D006801:Humans; D014672:Vectorcardiography / Q000379:methods*; D016276:Ventricular Function
keywords: Action potential duration; ECG simulation; T-wave alternans; Vectocardiography