Position-Dependent and Hidden Atrioventricular Dyssynchrony in Micra AV Leadless Pacemaker
1Department of Cardiology, Soka Municipal Hospital, Soka, Japan.
Pacing and Clinical Electrophysiology : PACE
|May 20, 2025
Summary
Leadless pacemakers like Micra AV can cause position-dependent issues. Careful analysis of signal variations and histograms is crucial for diagnosing and resolving symptoms.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Device Technology
Background:
- The Micra AV leadless pacemaker is designed to maintain atrioventricular (AV) synchrony in patients.
- AV synchrony is critical for effective cardiac function and patient well-being.
Observation:
- An 81-year-old male patient experienced nocturnal palpitations.
- Routine evaluations were normal, but rate histogram analysis showed an unusual pattern.
- Manual atrial mechanical (MAM) testing revealed position-dependent signal oversensing.
Findings:
- The patient exhibited position-dependent AV dyssynchrony, specifically oversensing in the left lateral position.
- This oversensing was linked to an increased A3 signal amplitude.
- Adjusting the A3 threshold and window end settings successfully resolved the patient's symptoms.
Implications:
- This case underscores the significance of evaluating body position-related signal variations in leadless pacemaker function.
- Rate histogram analysis is a valuable tool for identifying subtle pacemaker behavior issues.
- Optimizing pacemaker settings based on position-dependent findings can improve patient outcomes and device efficacy.
Keywords:
Micra AVatrioventricular dyssynchronymanual atrial mechanical testposition‐dependentrate histogramMore Related Videos
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