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Updated: Feb 26, 2026

In Vivo Surface Electrocardiography for Adult Zebrafish
Published on: August 1, 2019
The differential diagnosis of wide QRS complex tachycardia
William J Brady1, Amal Mattu2, Jeffrey Tabas3
1Departments of Emergency Medicine and Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States.
Abstract:
Wide complex tachycardia is defined as a cardiac rhythm with a rate greater than 100 beats/min (bpm) and a QRS complex duration greater than 0.10 to 0.12seconds (s) in the adult patient; wide complex tachycardia (WCT) in children is defined according to age-related metrics. The differential diagnosis of the WCT includes ventricular tachycardia and supraventricular tachycardia with aberrant intraventricular conduction, including both relatively benign and life-threatening dysrhythmias. This review focuses on the differential diagnosis of WCT with a discussion of strategies useful in making the appropriate diagnosis, when possible.
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Sinus Bradycardia: Originating from the sinoatrial (SA) node, sinus bradycardia involves slower impulses, resulting in a heart rate of less than 60 beats per minute (bpm). Causes include sleep, vagal stimulation, beta-blockers, hypothyroidism,...
Electrocardiogram
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