No other antiarrhythmic showed a significant effect on mortality compared with controls .
Class IA , IC , and III drugs are effective in maintaining sinus rhythm but increase adverse effects , and class IA drugs may increase mortality
BACKGROUND A variety of antiarrhythmic drugs have been used to prevent recurrence of atrial fibrillation after conversion to sinus rhythm .
We performed a systematic review to determine the effect of long-term treatment with those drugs on death , embolisms , adverse effects , and atrial fibrillation recurrence .
Use of metoprolol CR/XL to maintain sinus rhythm after conversion from persistent atrial fibrillation: a randomized, double-blind, placebo-controlled study.
OBJECTIVES The primary objective of the present study was to assess the efficacy of metoprolol CR/XL to reduce the risk of relapse after cardioversion of persistent atrial fibrillation to sinus rhythm . BACKGROUND Indirect data from studies with d , l sotalol provide evidence that the beta-blocking effects of the compound are important in maintaining sinus rhythm after cardioversion of atrial fibrillation . METHODS After successful conversion to sinus rhythm , 394 patients with a history of persistent atrial fibrillation were r and omly assigned to treatment with metoprolol CR/XL or placebo . The two treatment groups were similar with respect to all pretreatment characteristics . Patients were seen on an outpatient basis for recording of resting electrocardiogram ( ECG )  after one week , one , three and six months of follow-up or whenever they felt that they had a relapse into atrial fibrillation or experienced an adverse event . RESULTS In the metoprolol CR/XL group , 96 patients ( 48.7 % ) had a relapse into atrial fibrillation compared with 118 patients ( 59.9 % ) in the placebo group ( p = 0.005 ) . Heart rate in patients after a relapse into atrial fibrillation was significantly lower in the metoprolol group ( 98 + /- 23 beats/min ) than in the placebo group ( 107 + /- 27 beats/min ) . The rate of adverse events reported was similar in both groups when the difference in follow-up time was taken into account . CONCLUSIONS The results of this double-blind , placebo-controlled study in patients after cardioversion of persistent atrial fibrillation showed that metoprolol CR/XL was effective in preventing relapse into atrial fibrillation or flutter
No other antiarrhythmic showed a significant effect on mortality compared with controls .
Class IA , IC , and III drugs are effective in maintaining sinus rhythm but increase adverse effects , and class IA drugs may increase mortality
BACKGROUND A variety of antiarrhythmic drugs have been used to prevent recurrence of atrial fibrillation after conversion to sinus rhythm .
We performed a systematic review to determine the effect of long-term treatment with those drugs on death , embolisms , adverse effects , and atrial fibrillation recurrence .