General Information

Corvert (ibutilide fumarate injection) is an antiarrhythmic drug with predominantly class III (cardiac action potential prolongation) properties.

Corvert is specifically indicated for the rapid conversion of atrial fibrillation or atrial flutter of recent onset to sinus rhythm. Patients with atrial arrhythmias of longer duration are less likely to respond to Corvert.

The recommended initial dose of Corvert is in the table below. Ibutilide infusion should be stopped as soon as the presenting arrhythmia is terminated or in the event of sustained or non-sustained ventricular tachycardia, or marked prolongation of QT or QTc.

Second Infusion: If the arrhythmia does not terminate within 10 minutes after the end of the initial infusion, a second 10-minute infusion of equal strength may be administered 10 minutes after completion of the first infusion.

Patient Weight

Initial Infusion (over 10 minutes)

60 kg (132 lb)
or more

One vial
(1 mg ibutilide fumarate)

Less than 60 kg
(132 lb)

0.1 mL/kg
(0.01 mg/kg ibutilide fumarate)

Mechanism of Action

Corvert (ibutilide fumarate injection) prolongs action potential duration in isolated adult cardiac myocytes and increases both atrial and ventricular refractoriness in vivo, ie, class III electrophysiologic effects. Voltage clamp studies indicate that Corvert, at nanomolar concentrations, delays repolarization by activation of a slow, inward current (predominantly sodium), rather than by blocking outward potassium currents, which is the mechanism by which most other class III antiarrhythmics act. These effects lead to prolongation of atrial and ventricular action potential duration and refractoriness, the predominant electrophysiologic properties of Corvert in humans that are thought to be the basis for its antiarrhythmic effect.

Clinical Trial Results

The results of two, large, placebo-controlled, double-blind and randomized clinical trials demonstrated that, compared with placebo, Corvert Injection successfully and rapidly converted atrial fibrillation and flutter to normal rhythm. In a third study conducted in Europe, Covert compared favorably with another intravenous antiarrhythmic agent currently unavailable in the United States