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Ventricular ectopy and QTc-interval prolongation associated with dronedarone therapy.
Jaime E Gonzalez1, William H Sauer, Mori J Krantz
1University of Colorado School of Medicine, Division of Cardiology, Aurora, Colorado.
Pharmacotherapy
|July 10, 2013
Summary
Dronedarone, an antiarrhythmic drug, may prolong the QT interval and increase ventricular ectopy, even without causing torsade de pointes. Monitoring is advised for patients on dronedarone therapy.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Amiodarone effectively treats arrhythmias but has significant toxicity.
- Dronedarone was developed as a safer alternative with reduced organ toxicity and proarrhythmic potential.
Observation:
- A 66-year-old male patient initiated on dronedarone for atrial fibrillation developed malaise, fatigue, and palpitations.
- Holter monitoring revealed increased premature ventricular complexes and a prolonged rate-corrected QT (QTc) interval (525-760 ms).
Findings:
- Discontinuation of dronedarone led to symptom resolution and normalization of the QTc interval.
- The case highlights dronedarone's potential to prolong ventricular repolarization and increase triggered ectopy.
Implications:
- Caution is warranted when prescribing dronedarone, even in patients without pre-existing heart failure.
- Serial QTc interval monitoring and Holter monitoring for symptomatic patients on dronedarone are recommended.
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