Discussion The results of this systematic review have the potential to benefit thous and s of patients worldwide as well as healthcare systems and healthcare economy .
Background Atrial fibrillation is the most common arrhythmia of the heart with a prevalence of approximately 2 % in the western world .
Atrial flutter , another arrhythmia , occurs less often with an incidence of approximately 200,000 new patients per year in the USA .
Patients with atrial fibrillation and atrial flutter have an increased risk of death and morbidities .
The management of atrial fibrillation and atrial flutter is often based on interventions aim ing at either a rhythm control strategy or a rate control strategy .
The evidence on the comparable effects of these strategies is unclear .
This protocol for a systematic review aims at identifying the best overall treatment strategy for atrial fibrillation and atrial flutter .
Preliminary report: effect of encainide and flecainide on mortality in a randomized trial of arrhythmia suppression after myocardial infarction.
The occurrence of ventricular premature depolarizations in survivors of myocardial infa rct ion is a risk factor for subsequent sudden death , but whether antiarrhythmic therapy reduces the risk is not known . The Cardiac Arrhythmia Suppression Trial ( CAST ) is evaluating the effect of antiarrhythmic therapy ( encainide , flecainide , or moricizine ) in patients with asymptomatic or mildly symptomatic ventricular arrhythmia ( six or more ventricular premature beats per hour ) after myocardial infa rct ion . As of March 30 , 1989 , 2309 patients had been recruited for the initial drug-titration phase of the study : 1727 ( 75 percent ) had initial suppression of their arrhythmia ( as assessed by Holter recording ) through the use of one of the three study drugs and had been r and omly assigned to receive active drug or placebo . During an average of 10 months of follow-up , the patients treated with active drug had a higher rate of death from arrhythmia than the patients assigned to placebo . Encainide and flecainide accounted for the excess of deaths from arrhythmia and nonfatal cardiac arrests ( 33 of 730 patients taking encainide or flecainide [ 4.5 percent ] ; 9 of 725 taking placebo [ 1.2 percent ] ; relative risk , 3.6 ; 95 percent confidence interval , 1.7 to 8.5 ) . They also accounted for the higher total mortality ( 56 of 730 [ 7.7 percent ] and 22 of 725 [ 3.0 percent ] , respectively ; relative risk , 2.5 ; 95 percent confidence interval , 1.6 to 4.5 ) . Because of these results , the part of the trial involving encainide and flecainide has been discontinued . We conclude that neither encainide nor flecainide should be used in the treatment of patients with asymptomatic or minimally symptomatic ventricular arrhythmia after myocardial infa rct ion , even though these drugs may be effective initially in suppressing ventricular arrhythmia . Whether these results apply to other patients who might be c and i date s for antiarrhythmic therapy is unknown
Discussion The results of this systematic review have the potential to benefit thous and s of patients worldwide as well as healthcare systems and healthcare economy .
Background Atrial fibrillation is the most common arrhythmia of the heart with a prevalence of approximately 2 % in the western world .
Atrial flutter , another arrhythmia , occurs less often with an incidence of approximately 200,000 new patients per year in the USA .
Patients with atrial fibrillation and atrial flutter have an increased risk of death and morbidities .
The management of atrial fibrillation and atrial flutter is often based on interventions aim ing at either a rhythm control strategy or a rate control strategy .
The evidence on the comparable effects of these strategies is unclear .
This protocol for a systematic review aims at identifying the best overall treatment strategy for atrial fibrillation and atrial flutter .