Dronedarone: a new antiarrhythmic agent.

Dronedarone is an antiarrhythmic agent recently approved by the United States Food and Drug Administration for the reduction of cardiovascular-related hospitalizations in patients with paroxysmal or persistent atrial fibrillation or atrial flutter. The drug is a derivative of amiodarone and has been modified to reduce the organ toxicities frequently encountered with amiodarone. Dronedarone exerts its antiarrhythmic effects through multichannel blockade of the sodium, potassium, and calcium channels and also possesses antiadrenergic activity, thereby exhibiting pharmacologic effects of all four Vaughan Williams classes of antiarrhythmics. The efficacy of dronedarone for the maintenance of sinus rhythm, ventricular rate control, and reduction in cardiovascular-related hospitalizations has been demonstrated in several randomized, placebo-controlled trials. Although a high rate of gastrointestinal events (e.g., nausea, vomiting, and diarrhea) has been associated with dronedarone, more serious adverse events such as thyroid, liver, or pulmonary toxicities have not been observed. Because of a possible increase in mortality, dronedarone should be avoided in patients with New York Heart Association class IV or II-III heart failure with a recent decompensation. Given the efficacy and safety data currently available, dronedarone represents a reasonable alternative for maintenance of sinus rhythm in appropriately selected patients.