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Wide complex irregularly regular tachycardia with QRS alternation.
Gabriel Vanerio1, Daniel Banina Aguerre, Pablo Fernandez Banizi
1Arrhythmia Service, CASMU-INCC. Montevideo, Uruguay. gvanerio@yahoo.com
Journal of Electrocardiology
|August 30, 2008
Summary
A patient experienced symptomatic palpitations diagnosed via electrocardiogram (ECG) as an irregular wide complex tachycardia. Electrophysiology study results are discussed to determine the cause of this cardiac arrhythmia.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- A 44-year-old male presented with symptomatic rapid palpitations starting in January 2007.
- No prior history of syncope or family history of sudden cardiac death was reported.
Observation:
- Electrocardiogram (ECG) during sinus rhythm was normal.
- An episode in July 2007 revealed an irregular wide complex tachycardia with varying QRS morphology (left bundle-branch block with alternating pattern).
Findings:
- Differential diagnoses included supraventricular tachycardia with aberrant conduction and QRS alternans, atrial tachycardia with accessory pathway conduction, or ventricular tachycardia.
- An electrophysiology study was conducted to further investigate the arrhythmia.
Implications:
- This case highlights the diagnostic challenges in differentiating wide complex tachycardias.
- Electrophysiology study is crucial for definitive diagnosis and guiding treatment of complex cardiac arrhythmias.
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