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Related Experiment Video

Updated: Jul 12, 2025

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing

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Left bundle branch pacing in alternating bundle branch block.

Juan Benezet-Mazuecos¹, Adrian Baranchuk², Álvaro Lozano¹

¹Arrhythmia Unit, Cardiology Department, Hospital Universitario La Luz, Madrid, Spain.

Journal of Electrocardiology

|October 20, 2023

Summary

This study highlights left bundle branch pacing as a physiological solution for intermittent atrioventricular block with alternating bundle branch block. It effectively restored atrioventricular synchrony, offering a promising alternative to traditional pacing methods.

Keywords:

Alternating bundle branch block Left bundle branch pacing Physiological pacing

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Area of Science:

Cardiology
Electrophysiology
Cardiac Pacing

Background:

Intermittent atrioventricular (AV) block can present with complex conduction abnormalities, including alternating bundle branch block.
Standard pacing may not always provide optimal physiological synchrony in such cases.

Observation:

A patient with symptomatic intermittent AV block and alternating bundle branch block was monitored.
A high need for pacing was presumed due to the patient's condition.

Findings:

Conduction system pacing, specifically left bundle branch pacing (LBBP), was considered a more physiological alternative.
LBBP successfully restored stable atrioventricular synchrony.
The paced QRS complex following LBBP closely resembled the native QRS complex.

Implications:

Left bundle branch pacing may be a valuable and physiological pacing strategy for patients with intermittent AV block and alternating bundle branch block.
This approach can potentially improve cardiac synchrony and patient outcomes compared to conventional pacing.