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Paradoxical atrial undersensing: noise rate reversion or amplifier ringing?
Berry M Van Gelder1, Waldy Van Den Broek, Frank A Bracke
1Catharina Hospital, Eindhoven, The Netherlands. carlgr@cze.nl
Journal of Cardiovascular Electrophysiology
|September 19, 2006
Summary
High atrial signals during tachycardia can paradoxically cause pacemakers to lose atrial sensing. This occurs due to amplifier saturation, leading to atrial undersensing despite high-amplitude electrograms.
Area of Science:
- Electrophysiology
- Cardiovascular device technology
Background:
- Dual-chamber pacemakers are used to manage heart rhythm disorders.
- Atrial tachy-arrhythmias can trigger mode switching or noise rate reversion in these devices.
Observation:
- A paradoxical behavior of atrial sensitivity programming was observed in two patients with dual-chamber pacemakers.
- Intermittent and complete loss of atrial sensing occurred during atrial tachycardia when sensitivity was set higher.
Findings:
- The phenomenon is attributed to amplifier ringing, a state of amplifier saturation.
- This saturation disables atrial sensing despite high-amplitude atrial electrograms during tachycardia.
Implications:
- Clinicians must be aware of this paradoxical atrial undersensing during programming.
- Careful sensitivity programming is crucial in patients with high-amplitude atrial electrograms during tachycardia to ensure proper pacemaker function.
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