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 .
Surgical ablation of atrial fibrillation during mitral-valve surgery.
BACKGROUND Among patients undergoing mitral-valve surgery , 30 to 50 % present with atrial fibrillation , which is associated with reduced survival and increased risk of stroke .  Surgical ablation of atrial fibrillation has been widely adopted , but evidence regarding its safety and effectiveness is limited . METHODS We r and omly assigned 260 patients with persistent or long-st and ing persistent atrial fibrillation who required mitral-valve surgery  to undergo either surgical ablation ( ablation group ) or no ablation ( control group ) during the mitral-valve operation . Patients in the ablation group underwent further r and omization to pulmonary-vein isolation or a biatrial maze procedure . All patients underwent closure of the left atrial appendage . The primary end point was freedom from atrial fibrillation at both 6 months and 12 months ( as assessed by means of 3-day Holter monitoring ) . RESULTS More patients in the ablation group than in the control group were free from atrial fibrillation at both 6 and 12 months ( 63.2 % vs. 29.4 % , P<0.001 ) . There was no significant difference in the rate of freedom from atrial fibrillation between patients who underwent pulmonary-vein isolation and those who underwent the biatrial maze procedure ( 61.0 % and 66.0 % , respectively ; P=0.60 ) . One-year mortality was 6.8 % in the ablation group and 8.7 % in the control group ( hazard ratio with ablation , 0.76 ; 95 % confidence interval , 0.32 to 1.84 ; P=0.55 ) . Ablation was associated with more implantations of a permanent pacemaker than was no ablation ( 21.5 vs. 8.1 per 100 patient-years , P=0.01 ) . There were no significant between-group differences in major cardiac or cerebrovascular adverse events , overall serious adverse events , or hospital readmissions . CONCLUSIONS The addition of atrial fibrillation ablation to mitral-valve surgery significantly increased the rate of freedom from atrial fibrillation at 1 year among patients with persistent or long-st and ing persistent atrial fibrillation , but the risk of implantation of a permanent pacemaker was also increased . ( Funded by the National Institutes of Health and the Canadian Institutes of Health Research ; Clinical Trials.gov number , NCT00903370 . )
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 .