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 .
Conversion of recent onset paroxysmal atrial fibrillation to normal sinus rhythm: the effect of no treatment and high-dose amiodarone. A randomized, placebo-controlled study.
BACKGROUND Spontaneous conversion of recent onset paroxysmal atrial fibrillation  to  normal sinus rhythm  occurs commonly and is not affected by low-dose amiodarone treatment . METHODS In a r and omized , placebo-controlled trial of 100 patients with paroxysmal atrial fibrillation of recent onset ( < 48 h ) we compared the effects of treatment with continuous intravenous amiodarone 125 mg per hour ( total 3 g ) and intravenous placebo .  Patients in the placebo group who did not convert to normal sinus rhythm within 24 h were started on amiodarone therapy . RESULTS Conversion to normal sinus rhythm occurred within 24 h in 32 of 50 patients ( 64 % ) in the placebo group , most of whom converted within 8 h. Lower conversion rates were observed in patients with hypertension , ischaemic heart disease or congestive heart failure and in patients with echocardiographic findings of left atrial diameter above 45 mm , ejection fraction below 45 % or significant mitral regurgitation . However , in most patients these clinical or echocardiographic risk factors of decreases in conversion rate were not present . In such patients the spontaneous conversion rate was approximately 90 % . The conversion rate during 24 h of treatment in the amiodarone group was 92 % ( P=0.0017 , compared to the placebo group ) . In this group , the conversion rate was largely unaffected by baseline characteristics . Of the 18 patients who did not convert with placebo , 15 ( 85 % ) converted after being crossed over to amiodarone . All patients not responding to high-dose amiodarone were in chronic atrial fibrillation within 1 month . In patients still in atrial fibrillation after 8 h of treatment , the pulse rate decreased significantly more in the amiodarone as compared to the placebo group ( 83+/-15 vs 114+/-20 beats . min(-1 ) , P=0.0014 ) . CONCLUSION The spontaneous conversion of recent onset paroxysmal atrial fibrillation is high and approaches 90 % in specific clinical and echocardiographically defined subgroups . Intravenous high-dose amiodarone safely facilitates conversion of paroxysmal atrial fibrillation . However , such treatment should be reserved for patients with unfavourable risk factor profiles , not converting during 8 h of observation or requiring rate control
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 .