title: The prognostic significance of atrial fibrillation in heart failure with a preserved and reduced left ventricular function: insights from a meta-analysis.
abstract: BACKGROUND
  The prognostic significance of atrial fibrillation (AF) in patients with heart failure remains inconclusive.
  
  
  OBJECTIVE
  To perform a meta-analysis of the published data to study the prognostic significance of AF in heart failure patients and to determine whether this relates to the presence of preserved or reduced left ventricular systolic function.
  
  
  RESULTS
  We searched the MEDLINE (from inception to May 2014) supplemented by manual searches of references of relevant retrieved articles. Randomized clinic trials and observational studies were included with hazard ratios (HRs) of AF for mortality in chronic heart failure patients. The search strategy yielded 20 studies that met our eligibility criteria. A total of 61 240 AF patients in 152 306 heart failure participants were included, with 39 879 deaths occurring during follow-up. Pooled HRs for AF in mortality in heart failure was 1.17 (95% confidence intervals: 1.11-1.23) using random-effect model (I(2)  = 44.5%). There was a significant difference of combined HRs between heart failure patients with preserved and reduced left ventricular ejection fraction (LVEF) in separate analysis. Sensitivity analysis supported the consistence of the results.
  
  
  CONCLUSIONS
  Atrial fibrillation is significantly associated with increased mortality in heart failure patients. The prognostic significance of AF may be different between heart failure with preserved and reduced LVEF, and AF is associated with poorer prognosis in heart failure patients with preserved LVEF.
authors.affiliation: State Key Laboratory of Cardiovascular Disease, Department of Evidence Based Medicine, Fuwai Hospital, National Centre for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beili Shi Road 167, Beijing, China.
authors.forename: Min
authors.initials: M
authors.lastname: Cheng
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Lu
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Huang
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Gu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000503:physiopathology*; D005260:Female; D006333:Heart Failure / Q000401:mortality / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume / Q000502:physiology; D016019:Survival Analysis; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: Hazard ratio; Mortality; Preserved LVEF