Moreover all the anti-arrhythmic agents that are used in treatment of AF were potentially pro-arrhythmic especially in patients with coronary artery disease and structurally abnormal heart .
Although atrial fibrillation ( AF ) is the most common sustained arrhythmia seen during daily cardiovascular physician practice , its management remained a challenge for cardiology physician as there was no single anti-arrhythmic agents proved to be effective in converting atrial fibrillation and kept its effectiveness in maintaining sinus rhythm over long term .
Some of these drugs also have serious non cardiac side effects that limit its long term use in the management of atrial fibrillation .
Several new and investigational anti-arrhythmic agents are emerging but data supporting their effectiveness and safety are still limited .
Dronedarone for prevention of atrial fibrillation: a dose-ranging study.
AIMS Dronedarone , a benzofurane derivative without iodine substituents , shares the electrophysiologic properties of amiodarone . This study was design ed to determine the most appropriate dose of dronedarone for prevention of  atrial fibrillation ( AF )  after cardioversion . METHODS AND RESULTS Patients with persistent AF were r and omly allocated to 800 , 1200 , 1600 mg daily doses of dronedarone or placebo . The main analysis was conducted on 199/270 patients , who entered the maintenance phase following pharmacological cardioversion or , if unsuccessful , DC cardioversion . Within 6-month follow-up , the time to AF relapse increased on dronedarone 800 mg , with a median of 60 days vs 5.3 days in the placebo group ( relative risk reduction 55 % [ 95 % CI , 28 to 72 % ] P=0.001 ) . No significant effect was seen at higher doses . Spontaneous conversion to sinus rhythm on  dronedarone  occurred in 5.8 to 14.8 % of patients ( P=0.026 ) . There were no proarrhythmic reactions . Drug-induced QT prolongation was only noticed in the 1600 mg group . Premature drug discontinuations affected 22.6 % of subjects given 1600 mg dronedarone versus 3.9 % on 800 mg and were mainly due to gastrointestinal side effects . No evidence of thyroid , ocular or pulmonary toxicity was found . CONCLUSION Dronedarone , at a 800 mg daily dose , appears to be effective and safe for the prevention of AF relapses after cardioversion . The absence of thyroid side effects and of proarrhythmia are important features of the drug . Further studies are needed to better delineate the antiarrhythmic profile of the drug
Moreover all the anti-arrhythmic agents that are used in treatment of AF were potentially pro-arrhythmic especially in patients with coronary artery disease and structurally abnormal heart .
Although atrial fibrillation ( AF ) is the most common sustained arrhythmia seen during daily cardiovascular physician practice , its management remained a challenge for cardiology physician as there was no single anti-arrhythmic agents proved to be effective in converting atrial fibrillation and kept its effectiveness in maintaining sinus rhythm over long term .
Some of these drugs also have serious non cardiac side effects that limit its long term use in the management of atrial fibrillation .
Several new and investigational anti-arrhythmic agents are emerging but data supporting their effectiveness and safety are still limited .