Levofloxacin induced polymorphic ventricular tachycardia with normal QT interval

Area of Science:

• Cardiology
• Pharmacology
• Electrophysiology

Background:

• Polymorphic ventricular tachycardia (PVT) is a potentially life-threatening arrhythmia.
• Torsades de pointes, a specific type of PVT, is typically associated with a prolonged QT interval.
• Known causes of torsades de pointes include congenital long QT syndrome, certain medications, and electrolyte disturbances.

Observation:

• This report details a unique case of PVT occurring in a patient with a normal QT interval.
• The patient had no congenital long QT syndrome or other common predisposing factors for arrhythmias.
• The arrhythmia was temporally associated with the oral administration of levofloxacin.

Findings:

• The study identifies oral levofloxacin as a potential, previously unreported cause of polymorphic ventricular tachycardia with a normal QT interval.
• This finding expands the spectrum of drug-induced cardiac arrhythmias.
• Levofloxacin-induced PVT occurred despite a normal baseline QT interval, differentiating it from typical torsades de pointes.

Implications:

• Clinicians should consider levofloxacin as a potential cause of PVT, even in the absence of QT interval prolongation.
• This case highlights the importance of thorough medication review in patients presenting with unexplained ventricular arrhythmias.
• Further research is warranted to elucidate the mechanism of levofloxacin-induced PVT and its prevalence.