title: Brain natriuretic peptide is a marker associated with thrombus in stroke patients with atrial fibrillation.
abstract: BACKGROUND
  Patients with atrial fibrillation (AF) and atrial thrombus are at high risk of thromboembolic events. We investigated whether BNP levels can serve as a biological marker of thrombus.
  
  
  METHODS
  We prospectively enrolled patients with AF within 7days of an ischemic stroke and transient ischemic attack (TIA). We measured BNP levels in all patients while they underwent transesophageal echocardiography (TEE) and then assigned them to groups based on the presence (positive group) or absence (negative group) of left atrial thrombus. Factors associated with atrial thrombus were investigated using multivariate logistic regression analysis.
  
  
  RESULTS
  Of the 67 (male, n = 40; mean age, 76.5 ± 11.1 years) enrolled patients, 17 (25.4%) had left atrial thrombus. The incidence of hypertension was significantly higher in the positive, than in the negative group (88.2% vs. 58.0%, p = 0.020). The BNP level was also significantly higher in the positive, than in the negative group (median (interquartile range) 189.8 (141.4-473.2) vs. 117.9 (70.3-187.1) pg/ml, p=0.012). The optimal cut-off value, sensitivity, and specificity of BNP levels to distinguish the positive, from the negative group were 140.0 pg/ml, 76.5%, and 62.0%, respectively. Multivariate logistic regression analysis demonstrated that a BNP concentration of>140.0 pg/ml (odds ratio, 5.62; 95% CI, 1.39-22.66, p = 0.015) was an independent factor associated with thrombus.
  
  
  CONCLUSIONS
  Levels of BNP can serve as a marker of left atrial thrombus in acute ischemic stroke and TIA in patients with AF.
authors.affiliation: Department of Stroke Medicine, Kawasaki Medical School, Okayama, Japan. yokokada@mac.com
authors.forename: Yoko
authors.initials: Y
authors.lastname: Okada
authors.forename: Kensaku
authors.initials: K
authors.lastname: Shibazaki
authors.forename: Kazumi
authors.initials: K
authors.lastname: Kimura
authors.forename: Noriko
authors.initials: N
authors.lastname: Matsumoto
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Iguchi
authors.forename: Junya
authors.initials: J
authors.lastname: Aoki
authors.forename: Kazuto
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Kennichiro
authors.initials: K
authors.lastname: Sakai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000150:complications* / Q000000981:diagnostic imaging; D015415:Biomarkers; D002545:Brain Ischemia / Q000097:blood* / Q000150:complications; D015897:Comorbidity; D017548:Echocardiography, Transesophageal; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D015994:Incidence; D002546:Ischemic Attack, Transient / Q000097:blood / Q000150:complications; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013927:Thrombosis / Q000097:blood* / Q000000981:diagnostic imaging / Q000209:etiology
chemical_list: D015415:Biomarkers; D020097:Natriuretic Peptide, Brain