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Updated: Jun 13, 2026
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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Structural causes of right bundle branch block-time for a closer look?
1Department of Physiology, University of Pretoria, Pretoria, South Africa, PO Box 24318, Gesina, Pretoria, South Africa, 0031.
The Open Cardiovascular Medicine Journal
|April 14, 2010
Summary
A new type of right bundle branch block may exist, caused by a subaortic muscular tendon. This finding suggests examining endoventricular structures for structural causes of this electrocardiographic phenomenon.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Anatomy
Background:
- Right bundle branch block (RBBB) is a recognized electrocardiographic finding.
- Currently, RBBB is classified into proximal and distal variants.
- Various pathologies can lead to these RBBB forms.
Purpose of the Study:
- To propose a third type of right bundle branch block.
- To investigate the role of subaortic muscular tendons in RBBB.
- To explore novel structural causes of RBBB.
Main Methods:
- Electrocardiographic analysis.
- Review of cardiac pathologies.
- Hypothesized mechanism involving left ventricular conduction velocity.
Main Results:
- A potential third type of RBBB is suggested.
- This variant may result from a subaortic muscular tendon in the left ventricle.
- This structure could increase left ventricular conduction velocity, causing a 'relative' RBBB.
Conclusions:
- A third type of RBBB, linked to subaortic structures, is proposed.
- Further investigation into endoventricular structures is necessary for diagnosing RBBB.
- This could refine the understanding of RBBB's structural origins.
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