title: Atrial flutter: Clinical risk factors and adverse outcomes in the Framingham Heart Study.
abstract: BACKGROUND
  Few epidemiologic cohort studies have evaluated atrial flutter (flutter) as an arrhythmia distinct from atrial fibrillation (AF).
  
  
  OBJECTIVE
  The purpose of this study was to examine the clinical correlates of flutter and its associated outcomes to distinguish them from those associated with AF in the Framingham Heart Study.
  
  
  METHODS
  We reviewed and adjudicated electrocardiograms (ECGs) previously classified as flutter or AF/flutter and another 100 ECGs randomly selected from AF cases. We examined the clinical correlates of flutter by matching up to 5 AF and 5 referents to each flutter case using a nested case referent design. We determined the 10-year outcomes associated with flutter with Cox models.
  
  
  RESULTS
  During mean follow-up of 33.0 ± 12.2 years, 112 participants (mean age 72 ± 10 years, 30% women) developed flutter. In multivariable analyses, smoking (odds ratio [OR] 2.84, 95% confidence interval [CI] 1.54-5.23), increased PR interval (OR 1.28 per SD, 95% CI 1.03-1.60), myocardial infarction (OR 2.25, 95% CI 1.05-4.80) and heart failure (OR 5.22, 95% CI 1.26-21.64) were associated with incident flutter. In age- and sex-adjusted models, flutter (vs referents) was associated with 10-year increased risk of AF (hazard ratio [HR] 5.01, 95% CI 3.14-7.99), myocardial infarction (HR 3.05, 95% CI 1.42-6.59), heart failure (HR 4.14, 95% CI 1.90-8.99), stroke (HR 2.17, 95% CI 1.13-4.17), and mortality (HR 2.00, 95% CI 1.44-2.79).
  
  
  CONCLUSIONS
  We identified the clinical correlates associated with flutter and observed that flutter was associated with multiple adverse outcomes.
authors.affiliation: Department of Medicine, Boston University Medical Center, Boston, Massachusetts.
authors.forename: Faisal
authors.initials: F
authors.lastname: Rahman
authors.affiliation: Data Coordinating Center, Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Na
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Biostatistics, Boston University, Boston, Massachusetts.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Yin
authors.affiliation: Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, Massachusetts.
authors.forename: Patrick T
authors.initials: PT
authors.lastname: Ellinor
authors.affiliation: Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, Massachusetts.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Lubitz
authors.affiliation: Department of Medicine, Louisiana State University School of Medicine, New Orleans, Louisiana.
authors.forename: Paul A
authors.initials: PA
authors.lastname: LeLorier
authors.affiliation: National Heart Lung and Blood Institute and Boston University's Framingham Heart Study, Framingham, Massachusetts; Departments of Medicine and Quantitative Health Sciences, University of Massachusetts, Worcester, Massachusetts; Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts.
authors.forename: David D
authors.initials: DD
authors.lastname: McManus
authors.affiliation: Department of Biostatistics, Boston University, Boston, Massachusetts.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Sullivan
authors.affiliation: Data Coordinating Center, Boston University School of Public Health, Boston, Massachusetts; Department of Neurology, Boston University School of Medicine, Boston, Massachusetts.
authors.forename: Sudha
authors.initials: S
authors.lastname: Seshadri
authors.affiliation: National Heart Lung and Blood Institute and Boston University's Framingham Heart Study, Framingham, Massachusetts; Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Ramachandran S
authors.initials: RS
authors.lastname: Vasan
authors.affiliation: Section of Cardiovascular Medicine, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts; National Heart Lung and Blood Institute and Boston University's Framingham Heart Study, Framingham, Massachusetts; Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Emelia J
authors.initials: EJ
authors.lastname: Benjamin
authors.affiliation: Section of Cardiovascular Medicine, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts; National Heart Lung and Blood Institute and Boston University's Framingham Heart Study, Framingham, Massachusetts. Electronic address: jmagnani@bu.edu.
authors.forename: Jared W
authors.initials: JW
authors.lastname: Magnani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D001282:Atrial Flutter / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D015331:Cohort Studies; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000209:etiology; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology
keywords: Atrial fibrillation; Atrial flutter; Epidemiology; Outcomes; Risk factors