A review of the appropriate and inappropriate use of dronedarone: lessons learned from controlled studies and regulatory submission.

Dronedarone is a multichannel blocker with electrophysiologic effects similar to amiodarone. Dronedarone has been documented to prevent atrial fibrillation recurrences and also has efficacy in slowing the ventricular response during episodes of atrial fibrillation. However, in the ANDROMEDA trial, dronedarone was associated with increased mortality when tested in New York Heart Association (NYHA) III/IV patients with left ventricular ejection fractions of less than 35%, who also had a recent hospitalization for decompensated heart failure. When such high-risk patients with heart failure were excluded in the ATHENA trial, dronedarone treatment resulted in a statistical reduction in the composite primary end point of all-cause mortality or cardiovascular hospitalization. In ATHENA, dronedarone reduced cardiovascular hospitalizations even though in the DIONY-SOS trial dronedarone had less effect than amiodarone on suppressing atrial fibrillation recurrences. The most appropriate patients for treatment with dronedarone would be patients with a recent history of paroxysmal or persistent atrial fibrillation/atrial flutter (AF/AFL) that have associated risk factors per the inclusion criteria of ATHENA. Inappropriate patients would be those with class IV heart failure or recently hospitalized for heart failure within the last month from an acute decompensation, the main inclusion criteria in ANDROMEDA. Dronedarone is a novel, multichannel blocking antiarrhythmic agent that may have some pleiotropic effects in addition to its ability to suppress and maintain sinus rhythm and control the rate during AF/AFL recurrences.