An abrupt loss of capture during permanent His-bundle pacing: Assessment of mechanism underlying late capture
Hiroyuki Kato1, Satoshi Yanagisawa2, Ryusuke Ota1
1Department of Cardiology Japan Community Health Care Organization Chukyo Hospital Nagoya Japan.
Journal of Arrhythmia
|December 13, 2024
Insights
His-bundle pacing (HBP) can face capture threshold issues long-term. This case study shows an abrupt rise in His-bundle capture threshold and loss of capture after 3.5 years of stable HBP, highlighting potential chronic phase complications.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Device Technology
Background:
- Permanent His-bundle pacing (HBP) is an advanced bradycardia treatment.
- Maintaining stable His-bundle capture threshold is crucial for long-term pacing efficacy.
- Unexpected increases in pacing thresholds can lead to loss of capture and necessitate intervention.
Purpose of the Study:
- To report a rare case of acute His-bundle capture threshold rise after a prolonged period of stable HBP.
- To investigate potential causes for chronic His-bundle capture threshold instability.
- To emphasize the importance of monitoring pacing parameters even years after successful HBP implantation.
Main Methods:
- Case report presentation.
- Review of patient's pacing parameters and lead impedance over 3.5 years.
- Analysis of potential lead-related and tissue-related factors contributing to threshold changes.
Main Results:
- An abrupt increase in His-bundle capture threshold and subsequent loss of capture occurred after 3.5 years of stable HBP.
- The patient had a history of atrioventricular block treated with HBP.
- Potential contributing factors identified include local fibrosis around the lead helix and altered lead insertion angle.
Conclusions:
- Chronic His-bundle capture threshold elevation is a potential complication of permanent HBP.
- Local tissue changes, such as fibrosis, and lead geometry can impact long-term pacing stability.
- Continued vigilance and monitoring are essential for patients with permanent HBP to ensure optimal device function.
Abstract:
A His-bundle (HB) capture threshold rise is still a significant concern in permanent His-bundle pacing (HBP). We present a case where an abrupt increase in HB threshold and loss of capture occurred even after 3.5 years of stable permanent HBP for an atrioventricular block. The development of local fibrosis around the lead helix and the change in an insertion angle of the lead might adversely affect the HB capture threshold in the chronic phase.
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