[QRS alternans during ventricular tachycardia]
Marek Jastrzebski1, Piotr Gomuła
1I Klinika Kardiologii i Nadciśnienia Tetniczego, Szpital Uniwersytecki, 31-501 Kraków. mcjastrz@cyf-kr.edu.pl
Kardiologia Polska
|April 21, 2009
Summary
This study details a case of ventricular tachycardia misdiagnosed due to narrow QRS complexes. Ablation successfully treated the arrhythmia originating from Purkinje fibers.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Diagnostics
Background:
- A 70-year-old male with a history of inferior wall myocardial infarction experienced recurrent ventricular tachycardia.
- These episodes were frequently misdiagnosed as supraventricular tachycardia or atrial flutter.
Observation:
- The misdiagnoses were attributed to narrow QRS complexes and QRS alternans mimicking fusion beats.
- The ventricular tachycardia exhibited QRS morphology resembling idiopathic ventricular tachycardia.
Findings:
- The reentrant circuit likely involved the Purkinje fibers of the posterior fascicle.
- Successful ablation of the ventricular tachycardia was achieved via radiofrequency current application.
Implications:
- Accurate electrocardiogram interpretation is crucial for diagnosing ventricular tachycardia, especially post-myocardial infarction.
- Understanding Purkinje fiber involvement can guide ablation strategies for complex arrhythmias.
- This case highlights the importance of recognizing subtle electrocardiographic features in differentiating arrhythmias.
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