title: Monocyte-platelet aggregates and CD11b expression as markers for thrombogenicity in atrial fibrillation.
abstract: BACKGROUND
  A strong interdependence is known between atrial fibrillation (AF), inflammation and thrombogenesis. Monocyte-platelet aggregates (MPAs) are sensitive markers of platelets and monocyte activation. It is not known whether MPAs are associated with thrombogenicity in AF. Therefore, we examined differences in the content of MPAs and CD11b expression in patients with AF in dependence of the presence of atrial thrombus formation.
  
  
  METHODS
  107 patients with symptomatic AF underwent transesophageal echocardiography (TEE) before planned cardioversion or pulmonary vein isolation. Flow-cytometric quantification analysis was done on the day of performed TEE to determine the content of MPAs and the expression of CD11b on monocytes and granulocytes.
  
  
  RESULTS
  Compared to patients without thrombus (n = 80) those with an echocardiographic proven left atrium (LA) thrombus (n = 27) showed an increased extent of the risk factors age, diabetes and heart failure. The content of MPAs (147 ± 12 vs. 311 ± 29 cells/µl, p < 0.001) as well as the CD11b expression on monocytes (p < 0.05) and granulocytes (p < 0.05) were strongly associated with the existence of a LA thrombus. The content of MPAs and the CD11b expression remained independent predictors for LA thrombus after adjustment in logistic regression analysis and negatively correlated with left atrial appendage flow velocity. MPAs above 170 cells/µl (OR 34.2, p = 0.01) had a sensitivity of 96 % and a specificity of 73 % for predicting LA-thrombus.
  
  
  CONCLUSIONS
  The content of MPAs and the CD11b expression on monocytes and granulocytes are increased in AF-patients with proven thrombus formation. They seem to be appropriate biomarkers for stratification of thromboembolic risk in patients with AF.
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany. christian.pfluecke@mailbox.tu-dresden.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Pfluecke
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Tarnowski
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Lina
authors.initials: L
authors.lastname: Plichta
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Berndt
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Schumacher
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Ulbrich
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Forkmann
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Marian
authors.initials: M
authors.lastname: Christoph
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: David M
authors.initials: DM
authors.lastname: Poitz
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Wunderlich
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Ruth H
authors.initials: RH
authors.lastname: Strasser
authors.affiliation: Technische Universität Dresden, Heart Center Dresden, University Hospital, Fetscherstrasse 76, 01307, Dresden, Germany.
authors.forename: Karim
authors.initials: K
authors.lastname: Ibrahim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets / Q000378:metabolism*; D039481:CD11b Antigen / Q000097:blood*; D017548:Echocardiography, Transesophageal; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D016017:Odds Ratio; D010973:Platelet Adhesiveness; D011237:Predictive Value of Tests; D012307:Risk Factors; D013927:Thrombosis / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D039481:CD11b Antigen; C509295:ITGAM protein, human
keywords: Atrial fibrillation; Monocytes; Monocyte–platelet aggregates; Stroke, thromboembolism, inflammation; Thrombogenicity