title: Creatine kinase-MB elevation after stroke is not cardiac in origin: comparison with troponin T levels.
abstract: OBJECTIVE
  Creatine kinase-MB (CK-MB) increases in some patients with stroke, with no clear evidence of an acute coronary syndrome. Its elevations have been suggested to represent a biological marker for stroke-related myocardial injury. Troponin T has superior sensitivity and specificity to CK-MB in revealing minor myocardial injury. Therefore, we studied troponin T levels after stroke to determine whether troponin T increases in parallel to CK-MB.
  
  
  METHODS
  We made daily measurements of CK-MB, myoglobin, total creatine kinase (total CK), and troponin T levels up to day 5 in 32 patients with large hemispheric infarction and with no history of coronary heart disease. The daily enzyme levels were compared with those of a control group of 22 patients with neurological diseases other than stroke.
  
  
  RESULTS
  Serum CK-MB, myoglobin, and total CK levels were elevated above the cutoff value in 11, 26, and 20 patients with stroke, respectively. These enzyme levels gradually increased within the first 3 days and declined afterward. Troponin T did not exceed the reference range in any patients. One patient had elevated myoglobin and 3 had elevated total CK in the control group. The difference between groups was significant for CK-MB, myoglobin, and total CK at various time points.
  
  
  CONCLUSIONS
  Troponin T, a more specific biochemical marker of myocardial injury, does not increase after stroke. Normal troponin T along with elevated CK-MB signifies that CK-MB is not the biological marker for myocytolysis. CK-MB elevations in stroke patients are likely to be noncardiac in origin.
authors.affiliation: Department of Neurology, Hacettepe University Hospital, Ankara, Turkey. ayhmgh@hotmail.com
authors.forename: Hakan
authors.initials: H
authors.lastname: Ay
authors.forename: Ethem Murat
authors.initials: EM
authors.lastname: Arsava
authors.forename: Okay
authors.initials: O
authors.lastname: Saribaş
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis; D002545:Brain Ischemia / Q000201:enzymology; D003402:Creatine Kinase / Q000096:biosynthesis*; D052279:Creatine Kinase, MB Form; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis*; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000201:enzymology*; D009211:Myoglobin / Q000096:biosynthesis; D020521:Stroke / Q000201:enzymology*; D020107:Troponin T / Q000096:biosynthesis*
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D009211:Myoglobin; D020107:Troponin T; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form