An Elusive Case of Transient 6:1 High-Grade Atrioventricular Block Despite Normal Initial Testing
Colten L Witte1, David J Dillard1, Thomas D Mesaris1
1College of Osteopathic Medicine, Edward Via College of Osteopathic Medicine, Auburn, USA.
Cureus
|January 5, 2026
Summary
Recurrent syncope due to high-grade atrioventricular (AV) block was diagnosed in a patient with prior normal tests. An implantable loop recorder confirmed transient AV block, leading to pacemaker implantation.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Case Reports
Background:
- Recurrent syncope and vertigo can be debilitating symptoms.
- High-grade atrioventricular (AV) block is a significant cardiac conduction abnormality.
- Initial diagnostic evaluations for syncope may not always reveal the underlying cause.
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