Dronedarone ( Multaq ) is a benzofuran derivative with a pharmacological profile similar to Amiodarone but has a more rapid onset of action and a much shorter half-life ( 13-19 h ).
Researchers have evaluated the efficacy of Dronedarone in atrial fibrillation ( AF ) patients using dual-chamber pacemakers capable of quantifying atrial fibrillation burden.
Pacemakers were adjusted to optimize atrial fibrillation detection.
Patients with atrial fibrillation burden more than 1 % were randomized to Dronedarone 400 mg twice daily ( BID ) or placebo.
Pacemakers were interrogated after 4 and 12 weeks of treatment.
The primary endpoint was the change in atrial fibrillation burden from baseline over the 12-week treatment period.
Patients with permanent atrial fibrillation, severe / recently decompensated heart failure, and current use of antiarrhythmic drugs were excluded.
From 285 patients screened, 112 were randomized ( mean age 76 years, 60% male, 84% hypertensive, 65% with sick sinus syndrome, 26% with diabetes mellitus type II, 15% with heart failure ).
Baseline mean atrial fibrillation burden was 8.77% for placebo and 10.14% for Dronedarone.
Over the 12-week study period, atrial fibrillation burden compared to baseline decreased by 54.4% ( P = 0.0009 ) with Dronedarone and trended higher by 12.8% ( P = 0.450 ) with placebo.
The absolute change in burden was decreased by 5.5% in the Dronedarone group and increased by 1.1% in the placebo group.
Heart rate during atrial fibrillation was reduced to approximately 4 beats/min with Dronedarone ( P = 0.285 ).
Adverse events were higher with Dronedarone compared to placebo ( 65 vs 56% ).
In conclusion, Dronedarone reduced pacemaker-assessed the relative atrial fibrillation burden compared to baseline and placebo by over 50% during the 12-week observation period. ( Xagena )
Ezekowitz MD et al, J Interv Card Electrophysiol 2015; Epub ahead of print