Physiologic Pacing Targeting the His Bundle and Left Bundle Branch: a Review of the Literature
Seth D Scheetz1, Gaurav A Upadhyay2
1Department of Internal Medicine, University of Chicago Medicine, Chicago, USA.
Insights
Conduction system pacing (CSP) offers physiological ventricular activation. His bundle pacing and left bundle branch area pacing show promise for bradycardia and heart failure, but more research is needed.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Conduction system pacing (CSP) aims to restore physiological ventricular activation.
- Pacing targets include the His bundle and left bundle branch area.
- CSP offers an alternative to traditional ventricular pacing.
Purpose of the Study:
- To review the strengths, weaknesses, and clinical applications of His bundle pacing (HBP) and left bundle branch area pacing (LBBAP).
- To discuss the role of CSP in bradyarrhythmias and heart failure (HF).
Main Methods:
- Literature review of studies on His bundle pacing and left bundle branch area pacing.
- Analysis of clinical outcomes, procedural aspects, and limitations of CSP techniques.
Main Results:
- HBP is effective for bradyarrhythmias and QRS correction in cardiac resynchronization therapy (CRT), but faces challenges with implant complexity and rising thresholds.
- LBBAP demonstrates similar physiological benefits to HBP with potentially simpler implantation and more stable thresholds.
- Hybrid systems combining CSP with left ventricular pacing show potential for heart failure treatment and complex conduction blocks.
Conclusions:
- CSP, including HBP and LBBAP, presents promising physiological pacing strategies.
- Further randomized controlled trials are essential to establish definitive treatment paradigms for CSP in bradycardia and heart failure.
- Ongoing research is crucial for optimizing CSP techniques and expanding their clinical utility.
Purpose Of Review:
Conduction system pacing (CSP) has emerged as a means to preserve or restore physiological ventricular activation via pacing at the His bundle or at more distal targets in the conduction system, including the left bundle branch area. This review examines strengths, weaknesses, and clinical applications of CSP performed via these approaches.
Recent Findings:
His bundle pacing (HBP) has been successfully utilized for standard bradyarrhythmia indications and for QRS correction among patients receiving devices for cardiac resynchronization therapy (CRT). Limitations of HBP pacing have included implant complexity and rising pacing thresholds over time. Left bundle branch area pacing (LBBAP) appears to deliver similar physiological benefits with shorter implant times and more stable thresholds. More recently, hybrid systems utilizing HBP or LBBAP in combination with left ventricular leads have been used to treat heart failure (HF) patients, and may be useful in multilevel or mixed conduction blocks. There is growing interest in CSP for bradycardia and HF indications, although high quality data with randomized controlled trials are needed to help guide future treatment paradigms.
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