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Published on: June 20, 2020
Dofetilide-induced long QT and torsades de pointes
Mehmet K Aktas1, Abrar H Shah, Toshio Akiyama
1University of Rochester, Strong Memorial Hospital, Department of Cardiovascular Diseases, Rochester, NY 14642, USA. Mehmet_aktas@urmc.rochester.edu
Summary
Dofetilide, an antiarrhythmic drug, can prolong the QT interval, potentially causing torsades de pointes. This study examines four cases and discusses risk factors for this serious adverse event.
Area of Science:
- Pharmacology
- Cardiology
- Clinical Medicine
Background:
- Dofetilide is a Class III antiarrhythmic approved for atrial fibrillation and flutter.
- It selectively inhibits the rapid component of the delayed rectifier potassium current.
- This action prolongs the effective refractory period, a key mechanism in its antiarrhythmic effect.
Purpose of the Study:
- To report four cases of dofetilide-induced QT prolongation and torsades de pointes.
- To discuss the risk factors associated with these adverse events.
- To review the existing literature on dofetilide's cardiac effects.
Main Methods:
- Case report analysis of four patients experiencing adverse events.
- Literature review of studies on dofetilide, QT interval, and torsades de pointes.
Main Results:
- Four cases of dofetilide-induced QT prolongation and subsequent torsades de pointes were identified.
- The study highlights the potential for serious cardiac events with dofetilide use.
Conclusions:
- Dofetilide, while effective, carries a risk of QT prolongation and torsades de pointes.
- Identifying and managing risk factors is crucial for patient safety during dofetilide therapy.
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