Alternating QRS Morphologies and PR Intervals After Transcatheter Aortic Valve Replacement
Vivek T Kulkarni1,2, Naga Venkata K Pothineni2,3, Ramanan Kumareswaran2,3
1Division of Cardiovascular Medicine, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
JACC. Case Reports
|July 28, 2021
Summary
Alternating bundle branch block on electrocardiograms (ECG) indicates serious prognosis. This study explains the electrophysiological mechanism behind alternating bundle branch block with changing PR intervals.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Education
Background:
- Alternating bundle branch block on ECG is a significant clinical finding.
- This pattern carries important prognostic implications for patients.
- Understanding its electrophysiological basis is crucial for diagnosis.
Purpose of the Study:
- To explore the electrophysiological mechanism of alternating bundle branch block.
- To analyze a specific case presenting with alternating PR intervals alongside the block.
- To provide an educational resource for understanding this complex ECG finding.
Main Methods:
- Case study analysis of an electrocardiogram (ECG).
- Explanation of electrophysiological principles governing cardiac conduction.
- Focus on the transition between different bundle branch block patterns.
Main Results:
- Detailed electrophysiological explanation of alternating bundle branch block.
- Correlation between alternating bundle branch block and alternating PR intervals identified.
- Demonstration of the underlying conduction abnormalities.
Conclusions:
- The study elucidates the mechanism of alternating bundle branch block.
- Understanding this phenomenon aids in ECG interpretation and patient prognostication.
- This educational case serves as a beginner-level guide to complex cardiac conduction.
Keywords:
AV, atrioventricularBBB, bundle-branch blockECG, electrocardiogramLAF, left anterior fascicleLB, left bundleLBBB, left bundle-branch blockLPFB, left posterior fascicular blockRB, right bundleRBBB, right bundle-branch blockTAVR, transcatheter aortic valve replacementaortic valveelectrocardiogramvalve replacementMore Related Videos
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