title: Progression of paroxysmal to persistent atrial fibrillation: 10-year follow-up in the Canadian Registry of Atrial Fibrillation.
abstract: Progression from paroxysmal to persistent atrial fibrillation (AF) has important clinical implications and is relevant to the management of patients with AF.
  
  
  
  The purpose of this study was to define the long-term rate of progression from paroxysmal to persistent AF and the relevant clinical variables.
  
  
  
  The Canadian Registry of Atrial Fibrillation enrolled patients after a first electrocardiographic diagnosis of paroxysmal AF. Associations between baseline characteristics and clinical outcomes were evaluated using a multivariable Cox proportional hazard model and a competing risk model accounting for death as a competing risk, where appropriate.
  
  
  
  We enrolled 755 patients (61.7% men) aged between 14 and 91 years (mean age 61.2 ± 14.2 years). The median follow-up was 6.35 years (interquartile range 2.93-10.04 years), with a rate of progression to persistent AF at 1, 5, and 10 years was 8.6%, 24.3%, and 36.3%, respectively. All-cause mortality was 30.3% at 10 years. Factors associated with AF progression were increasing age (hazard ratio [HR] 1.40; 95% confidence interval [CI] 1.23-1.60, for each 10-year increment), mitral regurgitation (HR 1.87; 95% CI 1.28-2.73), left atrial dilatation (HR 3.01; 95% CI 2.03-4.47), aortic stenosis (HR 2.40; 95% CI 1.05-5.48), and left ventricular hypertrophy (HR .47; 95% CI 1.04-2.08). Factors associated with a lower rate of progression were a faster heart rate during AF (HR 0.94; 95% CI 0.92-0.96 per 5-beat/min increment) and angina (HR 0.54; 95% CI 0.38-0.77). After accounting for death as a competing risk, left ventricular hypertrophy and aortic stenosis were no longer significant.
  
  
  
  Within 10 years of presenting with paroxysmal AF, >50% of patients will progress to persistent AF or be dead. Increasing age, mitral regurgitation, aortic stenosis, left ventricular hypertrophy, and left atrial dilatation were associated with progression to persistent AF.
authors.affiliation: University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: Padfield
authors.affiliation: University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Christian
authors.initials: C
authors.lastname: Steinberg
authors.affiliation: University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Janice
authors.initials: J
authors.lastname: Swampillai
authors.affiliation: Centre for Health Evaluation & Outcome Sciences, UBC, Vancouver, British Columbia, Canada.
authors.forename: Hong
authors.initials: H
authors.lastname: Qian
authors.affiliation: McMaster University, Hamilton, Ontario, Canada.
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Connolly
authors.affiliation: University of Toronto, Toronto, Ontario, Canada.
authors.forename: Paul
authors.initials: P
authors.lastname: Dorian
authors.affiliation: University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
authors.forename: Martin S
authors.initials: MS
authors.lastname: Green
authors.affiliation: University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Karin H
authors.initials: KH
authors.lastname: Humphries
authors.affiliation: Western University, London, Ontario, Canada.
authors.forename: George J
authors.initials: GJ
authors.lastname: Klein
authors.affiliation: University of Calgary, Calgary, Alberta, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Sheldon
authors.affiliation: Montreal Heart Institute, Montreal, Quebec, Canada.
authors.forename: Mario
authors.initials: M
authors.lastname: Talajic
authors.affiliation: University of British Columbia, Vancouver, British Columbia, Canada. Electronic address: c-man1@shaw.ca.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Kerr
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D002170:Canada / Q000453:epidemiology; D002423:Cause of Death / Q000639:trends; D018450:Disease Progression; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D015996:Survival Rate / Q000639:trends; D013614:Tachycardia, Paroxysmal / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D055815:Young Adult
keywords: Atrial fibrillation; Long-term follow-up; Paroxysmal; Persistent; Progression; Registry; Risk factors