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Supra-his alternate-beat Wenckebach dysrhythmia
Mayo Clinic Proceedings
|August 1, 1975
Summary
Alternate-beat Wenckebach, a rare heart rhythm, was found in the A-V node, not the His bundle, in a patient with sick sinus syndrome. This study proposes electrophysiologic mechanisms for this unusual finding.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Arrhythmias
Background:
- Alternate-beat Wenckebach is an uncommon dysrhythmia.
- It is typically associated with block in the His bundle or bundle branches.
Purpose of the Study:
- To investigate the electrophysiologic mechanisms of A-V nodal (supra-His) alternate-beat Wenckebach.
- To analyze an unusual case of alternate-beat Wenckebach in a patient with sick sinus syndrome.
Main Methods:
- Utilized His bundle electrocardiography.
- Performed atrial pacing.
- Analyzed electrophysiologic data from a patient with sick sinus syndrome.
Main Results:
- Demonstrated A-V nodal (supra-His) alternate-beat Wenckebach during atrial pacing.
- Observed this dysrhythmia in a patient with features of sick sinus syndrome.
Conclusions:
- Proposed novel electrophysiologic mechanisms for supra-His Wenckebach.
- Highlighted that alternate-beat Wenckebach can originate proximal to the His bundle.
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