title: Mechanisms of early and delayed stroke after systematic off-pump coronary artery bypass.
abstract: OBJECTIVE
  Stroke is one of the most devastating complications after cardiac surgery. Off-pump coronary artery bypass (OPCAB) has been reported to offer a lower risk of stroke. However, limited information was available on timing and mechanisms of stroke after OPCAB. We sought to assess the incidence, timing, and mechanisms of stroke after OPCAB.
  
  
  METHODS
  A retrospective review of 1010 patients undergoing systematic OPCAB between 2001 and 2012. Stroke was defined as any focal or global neurologic deficits lasting for more than 24 hours. Stroke was classified as early stroke when it occurred less than 24 hours postoperatively, and delayed stroke when it occurred more than 24 hours postoperatively. Stroke mechanisms were classified as embolic or hypoperfusion.
  
  
  RESULTS
  In a total of 10 patients (1.0%) 11 episodes of stroke developed after OPCAB. Early stroke occurred in five (0.5%) patients and delayed stroke occurred in six (0.6%) patients. Of five early strokes, the mechanisms were embolic in two (40%) and hypoperfusion in three (60%). Of six delayed strokes, the mechanisms were embolic in five (83%) and unknown in one. Of six delayed strokes, all the patients had diabetes mellitus and acute cardiac events prior to surgery, and five patients had postoperative atrial fibrillation.
  
  
  CONCLUSIONS
  The incidence of stroke after systematic OPCAB was low. Early and delayed strokes were equally distributed. Stroke mechanisms were predominantly embolic. Early and delayed stroke differed in their mechanisms. Early and delayed stroke should be considered as two separate entities and different preventive strategies should be applied in future intervention.
authors.affiliation: Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Jeng-Wei
authors.initials: JW
authors.lastname: Chen
authors.affiliation: Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Cheng-Hsin
authors.initials: CH
authors.lastname: Lin
authors.affiliation: Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan. Electronic address: ronbin@ntuh.gov.tw.
authors.forename: Ron-Bin
authors.initials: RB
authors.lastname: Hsu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology* / Q000209:etiology*; D013624:Taiwan; D013997:Time Factors
keywords: mechanism; off-pump coronary artery bypass; stroke