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Utility of implantable cardioverter defibrillator electrograms to estimate repolarization alternans preceding a
Antonis A Armoundas1, Christine M Albert, Richard J Cohen
1Division of Molecular Cardiobiology, Johns Hopkins University, Baltimore, Maryland, USA. aarmoundas@partners.org
Abstract:
Electrical alternans is a pattern of variation in the shape of the ECG waveform that appears on an every-other-beat basis. In humans, alternation in ventricular repolarization, namely, repolarization alternans, has been associated with increased vulnerability to ventricular tachycardia/ventricular fibrillation and sudden cardiac death. This study investigates the utility of implantable cardioverter defibrillator electrograms to estimate repolarization alternans preceding a tachyarrhythmic event. It is demonstrated that microvolt-level repolarization alternans is present prior to an arrhythmic event, and one can record low-amplitude-noise signals that can be used to obtain reliable estimates of repolarization alternans. This study eventually may lead to new methods that would prevent the onset of malignant tachyarrhythmias.
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