Related Experiment Video
Updated: Jul 26, 2025

Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
Published on: July 5, 2021
The power of three: Atrial rate limit power-on-reset - A non-electromagnetic cause of pacemaker-induced extracardiac
Estelle Torbey1, Esseim Sharma1, Robert Betzold2
1Brigham and Women's Hospital, Arrhythmia Services Section, The Warren Alpert Medical School, Brown University, Boston, Massachusetts, Rhode Island, USA.
Background:
Power-on reset (PoR) is most commonly due to electromagnetic interference. Full PoR results in a switch to an inhibited mode (VVI) pacing and resets pacing outputs to maximal unipolar settings, leading to extracardiac stimulation.
Methods:
We present a case of PoR occurrence in the absence of electromagnetic interference, resulting in pectoral stimulation triggered by violation of the atrial rate limit.
Conclusions:
It is useful for clinicians to recognizethe occurrence of PoR in the setting of atrial limit violation andthe appropriate management in such circumstances.
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