Intermittent Interatrial Block in a Patient With Recurrent Transient Ischemic Attacks

Area of Science:

• Cardiology
• Neurology
• Electrophysiology

Background:

• Interatrial block (IAB) is a cardiac conduction disorder associated with atrial fibrillation (AF) and increased risk of ischemic stroke.
• Premature atrial complexes (PACs) can trigger intermittent IAB, potentially preceding AF development and thromboembolic events.

Observation:

• A case of embolic stroke of undetermined source (ESUS) is presented, where intermittent partial IAB was detected via electrocardiogram (ECG).
• Analysis of serial ECGs and Holter monitoring revealed dynamic P-wave changes indicative of intermittent partial IAB.
• No episodes of atrial fibrillation or other identifiable embolic sources were found during the monitoring period.

Findings:

• The study identified intermittent partial interatrial block in a patient with ESUS, characterized by dynamic ECG P-wave alterations.
• This finding occurred in the absence of diagnosed atrial fibrillation or other recognized causes of stroke.
• The intermittent nature of IAB suggests a potentially transient atrial electrical abnormality.

Implications:

• Intermittent IAB may serve as a marker of underlying atrial vulnerability in patients diagnosed with ESUS.
• Recognizing subtle and dynamic ECG changes associated with IAB could improve risk stratification for stroke.
• Early identification of intermittent IAB might facilitate targeted preventive strategies to reduce thromboembolic risk in susceptible individuals.