Levofloxacin induced polymorphic ventricular tachycardia with normal QT interval
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Updated: Oct 7, 2026

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
B Paltoo1, S O'Donoghue, M S Mousavi
1Section of Cardiology, Washington Hospital Center, 110 Irving St. NW, Washington, DC 20010, USA.
Abstract:
Polymorphic ventricular tachycardia (PVT) is a form of ventricular tachycardia characterized by QRS complexes that seem to change direction during the tachycardia. If associated with a prolonged QT interval, it is called torsades de pointes. In the absence of a congenital long QT syndrome, torsades is seen with certain drugs such as antiarrhythmic agents (Class IA, IC, III), psychotropic medications, antidepressants, antihistamines, and electrolyte disturbances. We report the first case of polymorphic ventricular tachycardia with normal QT interval associated with the oral use of levofloxacin in the absence of other etiologies known to cause these arrhythmias.
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