title: D-dimers predict stroke subtype when assessed early.
abstract: BACKGROUND
  Early classification of ischemic stroke subtype is important for secondary stroke prevention and may guide further investigations.
  
  
  METHODS
  Levels of coagulation activation [fibrinopeptide A (FPA), prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complex (TAT)] and fibrinolysis activation [plasmin-alpha(2)-antiplasmin complex (PAP), D-dimers] markers were measured in 98 consecutive patients with a first-ever acute ischemic stroke admitted within 12 h after symptom onset.
  
  
  RESULTS
  Median age was 67 years and 44% were women. Median time from symptom onset to blood sampling was 4 h. Stroke subtype was classified as 'cardioembolic' (54%), 'large-artery atherosclerosis' (11%), 'small-vessel disease' (5%), 'other determined' (9%) or 'undetermined etiology' (20%). Patients with cardioembolic stroke suffered more often from coronary artery disease than patients with other stroke etiologies (40 vs. 22%, p = 0.019). There were no differences in age, sex, stroke severity, time to blood sampling, frequency of hypertension, diabetes mellitus or current smoking. D-dimers (medians) were higher in patients with cardioembolic strokes than in those with other etiologies (615 vs. 322 microg/l, p < 0.001). No differences in F1+2, FPA, TAT or PAP levels were found. After multivariate analysis, higher D-dimer levels remained independently associated with cardioembolic stroke (p = 0.022). When measured within 6 h, D-dimers below 300 microg/l excluded cardioembolic stroke with a sensitivity of 100% and a specificity of 52%.
  
  
  CONCLUSIONS
  Low D-dimer levels in the first few hours make a cardioembolic stroke unlikely, and may be useful to guide further investigations. Other coagulation markers were not useful in differentiating between different stroke etiologies.
authors.affiliation: Department of Emergency Medicine, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland.
authors.forename: Jörg
authors.initials: J
authors.lastname: Isenegger
authors.forename: Niklaus
authors.initials: N
authors.lastname: Meier
authors.forename: Bernhard
authors.initials: B
authors.lastname: Lämmle
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Alberio
authors.forename: Urs
authors.initials: U
authors.lastname: Fischer
authors.forename: Krassen
authors.initials: K
authors.lastname: Nedeltchev
authors.forename: Jan
authors.initials: J
authors.lastname: Gralla
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Kohler
authors.forename: Heinrich P
authors.initials: HP
authors.lastname: Mattle
authors.forename: Marcel
authors.initials: M
authors.lastname: Arnold
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001777:Blood Coagulation; D002545:Brain Ischemia / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D004617:Embolism / Q000097:blood / Q000150:complications; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D005342:Fibrinolysis; D006331:Heart Diseases / Q000097:blood / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012307:Risk Factors; D012680:Sensitivity and Specificity; D020521:Stroke / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D