Utility of implantable cardioverter defibrillator electrograms to estimate repolarization alternans preceding a tachyarrhythmic event.
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.
Armoundas
Antonis A
AA
Division of Molecular Cardiobiology, Johns Hopkins University, Baltimore, Maryland, USA. aarmoundas@partners.org
Albert
Christine M
CM
Cohen
Richard J
RJ
Mela
Theofanie
T
D000465:Algorithms; D001145:Arrhythmias, Cardiac / Q000175:diagnosis; D017147:Defibrillators, Implantable; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D015716:Electrocardiography, Ambulatory / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D018570:Risk Assessment; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000175:diagnosis*