title: Troponin elevation predicts atrial fibrillation in patients with stroke or transient ischemic attack.
abstract: BACKGROUND
  Atrial fibrillation (AF) is a major cause of ischemic stroke. Cardiac troponin (cTnI) is a marker of myocardial damage and may predict arrhythmia. We sought to determine if increased cTnI levels were a predictor of new-onset AF in ischemic stroke or patients with transient ischemic attack (TIA).
  
  
  METHODS
  Consecutive patients who presented to Charles-Lemoyne Hospital between October 2006 and November 2010 with a diagnosis of acute ischemic stroke or TIA, without a history of AF, with a baseline measurement of cTnI were included in the study. The primary outcome was new-onset AF on 24-hour Holter measurement within 1 week of admission in patients without AF on the baseline electrocardiogram (ECG). Secondary outcomes included AF on Holter measurement, death, myocardial infarction (MI), and stroke within 3 months.
  
  
  RESULTS
  A total of 408 patients were included. Forty-six patients (11.3%) had elevated cTnI levels. These patients were older and had a higher prevalence of coronary artery disease and diabetes. AF on baseline ECG or 24-hour Holter measurement was present in 51 patients (12.5%) and was more frequent among patients with increased cTnI levels compared to patients with normal cTnI levels (34.7% vs 9.7%; P = .004 multivariate analysis). Elevated cTnI levels also predicted the composite outcome of stroke, MI, and death at 3 months (50.0% vs 16.1%; P = .0001).
  
  
  CONCLUSIONS
  cTnI elevation predicts new-onset AF on 24-hour Holter measurement in patients with acute ischemic stroke or TIA and may indicate a poorer prognosis and a higher risk of stroke, MI, and death at 3 months.
authors.affiliation: Division of Neurology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke University, Sherbrooke, Québec, Canada. Electronic address: isabelle.beaulieu-boire@usherbrooke.ca.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Beaulieu-Boire
authors.forename: Nancy
authors.initials: N
authors.lastname: Leblanc
authors.forename: Léo
authors.initials: L
authors.lastname: Berger
authors.forename: Jean-Martin
authors.initials: JM
authors.lastname: Boulanger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000097:blood* / Q000150:complications; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000097:blood* / Q000150:complications; D014336:Troponin / Q000097:blood*
chemical_list: D014336:Troponin