Author + information
- Received March 22, 2004
- Revision received June 5, 2004
- Accepted June 14, 2004
- Published online September 15, 2004.
- Elizabeth S. Kaufman, MD, FACC*,* (, )
- Paul A. Zimmermann, MD, FACC†,
- Ted Wang, MD, FACC‡,
- George W. Dennish III, MD, FACC§,
- Patrick D. Barrell, BS∥,
- Mary L. Chandler, MD, FACOG∥,
- H.Leon Greene, MD, FACC∥,
- AFFIRM Investigators
- ↵*Reprint requests and correspondence:
Dr. Elizabeth S. Kaufman, Heart and Vascular Research Center, Hamann 3rd Floor, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Cleveland, Ohio 44109-1998
Objectives This study examined the risk of proarrhythmic events in patients receiving antiarrhythmic drugs for treatment of atrial fibrillation (AF) according to present-day safety guidelines.
Background Advances in understanding the proarrhythmic risk of antiarrhythmic drugs has led to development of safety guidelines for these agents. Such guidelines were used in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study.
Methods This study was an analysis of the risk of arrhythmic events (arrhythmic death, resuscitated cardiac arrest, sustained ventricular tachycardia (VT), and torsade de pointes VT) in the antiarrhythmic drug arm of the AFFIRM study. Each time an antiarrhythmic drug was begun, it was counted as an exposure to that drug and the risk of an arrhythmic event was calculated.
Results A total of 2,033 patients received 3,030 exposures to antiarrhythmic drugs. Ninety-six arrhythmic events occurred by six years. Patients with a left ventricular ejection fraction <40% had more arrhythmic events. Twelve documented cases of torsade de pointes VT were noted. The incidence of torsade de pointes was 0.6% at five years (95% confidence interval 0.32 to 1.07).
Conclusions The overall risk of adverse arrhythmic events upon exposure to antiarrhythmic drugs in the AFFIRM study was reasonably low. Strict criteria for the safe use of antiarrhythmic drugs were successful in minimizing proarrhythmic events.
Supported under contract N01-HC-55139 by the National Heart, Lung, and Blood Institute. The AFFIRM investigators and their affiliations are listed in reference 8.
- Received March 22, 2004.
- Revision received June 5, 2004.
- Accepted June 14, 2004.
- American College of Cardiology Foundation