title: Stroke after cardiac surgery--hemispheric distribution and survival.
abstract: OBJECTIVE
  Stroke following cardiac surgery may occur either in association with surgery (early) or occur postoperatively (delayed). The hemispheric distribution of lesions may provide information about embolic routes, which was analyzed here.
  
  
  METHODS
  In 10,809 patients undergoing cardiac surgery, early (n = 223) and delayed stroke (n = 116) were explored. Symptoms and computed tomography findings were evaluated to categorize hemispheric distributions. This was compared with pre- and intra-operative characteristics and survival, using logistic regression and Kaplan-Meier statistics.
  
  
  RESULTS
  Early stroke had preponderance for the right rather than the left hemisphere (P = 0.009), whereas delayed stroke had a uniform distribution. Several intraoperative variables predicted the development of bilateral stroke compared with its unilateral counterpart. At multivariable analysis, the use of tranexamic acid was associated with bilateral stroke (P = 0.017), but was also associated with right rather than left-hemispheric stroke (P = 0.001). Bilateral lesions dramatically impaired survival versus those with unilateral lesions (P < 0.001). There was no survival difference between left and right-hemispheric stroke.
  
  
  CONCLUSIONS
  When stroke, after cardiac surgery, is subdivided into early and delayed forms, it becomes evident that early, but not delayed stroke, demonstrates a hemispheric side difference. The preponderance for right-hemispheric lesions may indicate embolic mechanisms routed via the brachiocephalic trunk.
authors.affiliation: Department of Surgical and Perioperative Science, Heart Center, Cardiothoracic Division, Umeå University, Umeå, Sweden. magnus.hedberg@karolinska.se
authors.forename: Magnus
authors.initials: M
authors.lastname: Hedberg
authors.forename: Karl Gunnar
authors.initials: KG
authors.lastname: Engström
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000209:etiology* / Q000401:mortality; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000401:mortality; D002533:Cerebral Angiography / Q000379:methods; D054022:Cerebrum / Q000098:blood supply* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012307:Risk Factors; D020521:Stroke / Q000000981:diagnostic imaging / Q000209:etiology* / Q000401:mortality; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants