[Interatrial block and its clinical relevance. Renaissance of an ECG change]

Area of Science:

• Cardiology
• Electrophysiology
• Medical Diagnostics

Background:

• Interatrial block (IAB) is a conduction delay between the right and left atria during normal sinus rhythm.
• IAB is an under-recognized electrocardiogram (ECG) finding with potential clinical implications.
• Bayés syndrome is a proposed term for interatrial block.

Purpose of the Study:

• To review the classification of interatrial block.
• To describe the pathomechanism of interatrial block.
• To highlight the clinical significance of interatrial block and aid its recognition through ECG examples.

Main Methods:

• Literature review of interatrial block.
• Analysis of electrocardiogram (ECG) criteria for interatrial block.
• Presentation of illustrative ECG cases.

Main Results:

• Interatrial block is classified based on ECG criteria reflecting conduction delay.
• The pathomechanism involves slowed or blocked conduction across the atria.
• Specific ECG patterns are presented to identify different types of interatrial blocks.

Conclusions:

• Interatrial block is a distinct ECG entity with clinical relevance.
• Accurate recognition of interatrial block requires understanding its classification and ECG manifestations.
• Bayés syndrome provides a framework for understanding and diagnosing interatrial block.