Alternating bundle branch block with alternating PR interval
Sudipta Mondal1, Anubhav Chatterjee1, Tapan Kr Matia1
1Department of Cardiology, The Mission Hospital, Durgapur 713212, West Bengal, India.
Journal of Electrocardiology
|September 13, 2025
Summary
A sexagenarian man experienced syncope due to alternating bundle branch block and alternating PR interval on ECG. This case highlights a rare cardiac conduction abnormality in a patient with a structurally normal heart.
Area of Science:
- Cardiology
- Electrophysiology
- Internal Medicine
Background:
- Syncope is a common clinical presentation, often requiring thorough investigation.
- Bundle branch block and PR interval variations can indicate underlying cardiac conduction system disease.
Purpose of the Study:
- To explore the potential mechanism behind alternating bundle branch block and alternating PR interval in a patient presenting with syncope.
- To correlate electrocardiographic findings with clinical presentation in a case of cardiac conduction abnormality.
Main Methods:
- Case report of a sexagenarian male presenting with syncope.
- Electrocardiogram (ECG) analysis revealing alternating bundle branch block and alternating PR interval.
- Cardiac biomarker assessment and echocardiography to evaluate cardiac structure and function.
Main Results:
- The patient presented with a single episode of syncope.
- ECG demonstrated alternating bundle branch block and alternating PR interval.
- Cardiac biomarkers were negative, and echocardiogram showed a structurally normal heart.
Conclusions:
- The findings suggest a complex disturbance in cardiac electrical conduction.
- Further investigation may be warranted to elucidate the precise electrophysiological mechanism of these alternating conduction abnormalities.
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