Morphology discrimination in implantable cardioverter-defibrillators: consistency of template match percentage during atrial tachyarrhythmias at different heart rates.

Background: Morphology discrimination (MD) in implantable cardioverter-defibrillators (ICDs) is based on the comparison of the ventricular electrogram during tachycardia with a stored reference template obtained during baseline rhythm. However, the effect of heart rate on the template match percentage during supraventricular tachyarrhythmias (SVT) is not known. The purpose of this study was to evaluate the performance of the template match percentage during SVT at different heart rates.