Novel Pacemaker-Mediated Arrhythmia Without Ventriculoatrial Conduction Can Induce Atrial Fibrillation.

Cardiovascular implantable electronic devices can initiate and sustain pacemaker-mediated arrhythmias. Endless loop tachycardia and repetitive non-re-entrant ventriculoatrial synchrony (RNRVAS) are well-described examples of pacemaker-mediated arrhythmias. However, such arrhythmias only occur in the presence of ventriculoatrial conduction. We identified a novel pacemaker-mediated arrhythmia that closely mimics RNRVAS but in the absence of ventriculoatrial conduction. We identified these arrhythmias in 9 patients, all with a St. Jude Medical/Abbott device, recorded as inappropriate mode-switch episodes by a device algorithm that includes paced events in the atrial counter. This report describes the mechanism, discusses clinical implications, and outlines programming options to eliminate this pseudo-RNRVAS.
Competing Interests: Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(Copyright © 2021 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)