title: Postoperative atrial fibrillation is a major cause of stroke after on-pump coronary artery bypass surgery.
abstract: BACKGROUND
  Atrial fibrillation, occurring after coronary artery bypass grafting (CABG), has been suggested to be associated with the development of postoperative stroke. However, it is not clear what is the incidence of atrial fibrillation-related postoperative stroke, the timing of its occurrence, and the outcome. These issues have been investigated in a consecutive series of patients who have undergone on-pump coronary artery bypass grafting (ONCAB).
  
  
  METHODS
  Among 2,630 patients who underwent ONCAB, 52 patients (2.0%) experienced postoperative stroke and form the basis of the present study.
  
  
  RESULTS
  Twelve patients (23.1%) died postoperatively. The ischemic cerebral event occurred after a mean of 3.7 days (range, 0 to 33). In 19 patients (36.5%), atrial fibrillation preceded the occurrence of neurologic complication. These patients experienced a mean of 2.5 episodes of atrial fibrillation before the occurrence of neurologic complication. The cerebrovascular event occurred after a mean of 6.0 days in patients in whom atrial fibrillation preceded it, after a mean of 1.2 days in those with calcified ascending aorta, and after a mean of 3.1 days in those without calcified ascending aorta or in whom atrial fibrillation did not precede the cerebrovascular complication (p < 0.0001). Stroke occurred a mean of 21.3 hours after atrial fibrillation.
  
  
  CONCLUSIONS
  This study confirmed that atrial fibrillation, occurring after CABG, is a major determinant of postoperative stroke. Prevention of postoperative atrial fibrillation, and of formation of clots into the left atrium, may dramatically reduce the risk of postoperative stroke.
authors.affiliation: Division of Cardiothoracic and Vascular Surgery, Department of Surgery, University of Oulu and Oulu University Hospital, Oulu, Finland.
authors.forename: Jarmo
authors.initials: J
authors.lastname: Lahtinen
authors.forename: Fausto
authors.initials: F
authors.lastname: Biancari
authors.forename: Esa
authors.initials: E
authors.lastname: Salmela
authors.forename: Martti
authors.initials: M
authors.lastname: Mosorin
authors.forename: Jari
authors.initials: J
authors.lastname: Satta
authors.forename: Pekka
authors.initials: P
authors.lastname: Rainio
authors.forename: Jussi
authors.initials: J
authors.lastname: Rimpiläinen
authors.forename: Martti
authors.initials: M
authors.lastname: Lepojärvi
authors.forename: Tatu
authors.initials: T
authors.lastname: Juvonen
mesh_terms: D001018:Aortic Diseases / Q000150:complications; D001281:Atrial Fibrillation / Q000209:etiology*; D002114:Calcinosis / Q000150:complications; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors; D020521:Stroke / Q000209:etiology*