title: High serum levels of pro-brain natriuretic peptide (pro BNP) identify cardioembolic origin in undetermined stroke.
abstract: BACKGROUND
  Stroke subtype diagnosis leads to specific therapies to reduce recurrences. Because nearly one third of patients remain with unknown etiology after a complete screening workup, we aim to investigate whether molecular markers of myocardial damage were associated with cardioembolic stroke and if they were useful to reclassify strokes of undetermined etiology.
  
  
  METHODS
  We included 262 patients with first ischemic stroke within the first 12 hours. Stroke subtype was evaluated by TOAST criteria. Stroke of undetermined origin were reclassified into likely atherothrombotic or likely cardioembolic according to a predefined non-validated algorithm. Blood samples were obtained on admission to determine serum levels of molecular markers (pro-BNP, pro-ANP and CK-MB) of myocardial damage.
  
  
  RESULTS
  Patients with cardioembolic infarct showed higher levels of pro-BNP, pro-ANP and CK-MB. Pro-BNP > 360 pg/mL was independently associated with cardioembolic stroke (OR: 28.51, CI95%: 5.90-136.75, p< 0.0001). Stroke etiology was undetermined in 82 patients (31%); 34 were reclassified as likely cardioembolic, 22 as likely atherothrombotic, and 26 remained as undetermined. Pro-BNP > 360 pg/mL was the only factor independently associated with likely cardioembolic stroke.
  
  
  CONCLUSIONS
  Pro-BNP levels higher than 360 pg/mL are associated with cardioembolic stroke and may be useful to reclassify undetermined strokes as of cardioembolic origin.
authors.affiliation: Clinical Neuroscience Research Laboratory, Department of Neurology, Hospital Clínico Universitario, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Rodríguez-Yáñez
authors.forename: Tomás
authors.initials: T
authors.lastname: Sobrino
authors.forename: Miguel
authors.initials: M
authors.lastname: Blanco
authors.forename: Natalia Pérez
authors.initials: NP
authors.lastname: de la Ossa
authors.forename: David
authors.initials: D
authors.lastname: Brea
authors.forename: Raquel
authors.initials: R
authors.lastname: Rodríguez-González
authors.forename: Rogelio
authors.initials: R
authors.lastname: Leira
authors.forename: Antonio
authors.initials: A
authors.lastname: Dávalos
authors.forename: José
authors.initials: J
authors.lastname: Castillo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D009320:Atrial Natriuretic Factor / Q000096:biosynthesis / Q000097:blood; D015415:Biomarkers; D020520:Brain Infarction / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism*; D052279:Creatine Kinase, MB Form / Q000096:biosynthesis / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000096:biosynthesis / Q000097:blood*; D010446:Peptide Fragments / Q000096:biosynthesis / Q000097:blood*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor; D052279:Creatine Kinase, MB Form