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Intermittent interatrial block after electrical cardioversion for atrial fibrillation
Adrian Baranchuk1, Kevin Michael, Uzma Syed
1Arrhythmia Service, Kingston General Hospital, Queen's University, Kingston, Ontario, Canada. barancha@kgh.kari.net
Journal of Electrocardiology
|May 9, 2008
Summary
Electrical cardioversion for atrial fibrillation can reveal intermittent interatrial block (IAB). This ECG finding, noted post-cardioversion, may warrant further investigation into its prognostic significance in patients with atrial fibrillation.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- Atrial fibrillation (AF) is a common arrhythmia requiring management.
- Electrical cardioversion is a standard procedure to restore normal sinus rhythm in AF patients.
Observation:
- A 67-year-old woman underwent successful electrical cardioversion for persistent AF.
- Post-cardioversion ECG revealed intermittent interatrial block (IAB), characterized by varying P-wave morphology.
- IAB persisted despite a recurrence of AF and a subsequent successful cardioversion.
Findings:
- Intermittent interatrial block (IAB) was observed on ECG after electrical cardioversion for atrial fibrillation.
- The presence of IAB was noted even after AF recurrence and successful cardioversion.
- The patient was discharged with evidence of IAB on ECG.
Implications:
- This case highlights the potential for electrical cardioversion to unmask or reveal intermittent interatrial block (IAB).
- The prognostic significance of postcardioversion IAB in atrial fibrillation warrants further clinical investigation.
- Understanding IAB's role post-cardioversion may refine risk stratification and management strategies for AF patients.
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