Therapeutic Flecainide Toxicity Causing VT Storm.
Kiriti Vattikonda1, Christopher J Peterson1, Brian Anyanwu1
1Department of Internal Medicine, Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA.
JACC. Case Reports
|January 31, 2025
Summary
Ventricular tachycardia (VT) storm can be fatal. This case highlights flecainide toxicity, even at therapeutic levels, as a potential cause of VT storm in patients taking this medication.
Area of Science:
- Cardiology
- Clinical Toxicology
Background:
- Ventricular tachycardia (VT) storm is a life-threatening cardiac arrhythmia.
- Multiple factors can contribute to the development of VT storm.
- Flecainide is an antiarrhythmic medication used to treat certain heart rhythm disorders.
Observation:
- A case study of a 71-year-old woman experiencing VT storm is presented.
- The patient developed VT storm while on flecainide therapy.
- The flecainide levels in this patient were within the therapeutic range.
Findings:
- Flecainide toxicity can precipitate VT storm, even when drug levels are considered therapeutic.
- This suggests a need for careful monitoring of patients on flecainide, irrespective of standard therapeutic ranges.
Implications:
- Clinicians should consider flecainide toxicity in the differential diagnosis for any patient presenting with VT storm.
- This case underscores the importance of recognizing atypical drug toxicity presentations.
- Further investigation into the mechanisms of flecainide-induced cardiotoxicity at therapeutic levels may be warranted.
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