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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

This summary is machine-generated.

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.

Keywords:

Alternating bundle branch block Atypical Infrahisian Wenckebach

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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.