Study Design

Study Design:

Patients Enrolled: 96
NYHA Class: 47% of patients had NYHA class II or III congestive heart failure.
Mean Follow Up: 30 days
Mean Patient Age: 28-86
Female: 29

Patient Populations:

Sustained atrial fibrillation or atrial flutter of a duration from one hour to six months, hemodynamic stability, and discontinuation of class I or III antiarrhythmic medications for at least five half-lives

Exclusions:

Symptoms of uncontrolled heart failure, prior myocardial infarction, unstable angina, or cardiac arrest; or cardiac surgery within 3 weeks, age <18 years, thyrotoxicosis, history of torsades de pointes, serum potassium level <3.6 or >5.5 mmol/l, resting heart rate <60 bpm, or QTc interval >440 ms

Primary Endpoints:

Conversion of atrial fibrillation or atrial flutter to sinus rhythm within three hours of initiation of therapy

Secondary Endpoints:

Evaluation of ventricular rate before and after administration of therapy in patients not converting to sinus rhythm

Drug/Procedures Used:

Patients were randomized to dofetilide or placebo in a 2:1 distribution. Intravenous dofetilide (8 μg/kg) or placebo was administered over 30 minutes. Patients were monitored continuously with single-lead electrocardiography and a Holter recording throughout the study period up to 24 hours.

Concomitant Medications:

All patients had any class I or III antiarrhythmic medications discontinued for greater than five half-lives prior to enrollment. Prestudy medications continued through the study period included digoxin (73%), beta-blockers (13%), and calcium channel antagonists (32%).