title: Induction of monocyte tissue factor procoagulant activity during coronary artery bypass surgery is reduced with heparin-coated extracorporeal circuit.
abstract: The possible activation of monocytes to express tissue factor procoagulant activity (TF-PCA) during CPB (cardiopulmonary bypass) was investigated. 22 patients undergoing myocardial revascularization were randomly assigned to two groups. In group C, heparin-coated circuits (Duraflo II) and reduced systemic heparinization (ACT > 250s) were used. In group NC, non-coated circuits and standard heparin administration (ACT > 480s) were used. Adherent monocytes retrieved from the oxygenators immediately after bypass arrest showed a 2-3-fold increase in TF-PCA when compared to circulating cells pre-CPB (P < 0.01). When cell PCA was expressed as percent change from pre-CPB (baseline) values, circulating monocytes in group NC at CPB-arrest showed a 2-fold increase in PCA compared to group C (P < 0.05). Moreover, the percent increase in PCA of oxygenator-retrieved monocytes was 7-fold in group NC and 2-fold in group C (P < 0.008 and P < 0.004, respectively). Thus, heparin-coating of the extracorporeal circuit reduced induction of adherent cell TF-PCA by 70% (P < 0.05). Thus, monocyte TF-PCA may cause activation of the extrinsic coagulation pathway during CPB surgery. It is apparent that heparin-coating enhanced biocompatibility of extracorporeal circuits. Reduced systemic heparinization in group C proved to be safe. However, further reduction of heparin administration may not be advisable, since monocytes were still activated in the coated oxygenator.
authors.affiliation: Nycomed Pharma AS, Oslo, Norway.
authors.forename: R M
authors.initials: RM
authors.lastname: Barstad
authors.forename: E
authors.initials: E
authors.lastname: Ovrum
authors.forename: M A
authors.initials: MA
authors.lastname: Ringdal
authors.forename: R
authors.initials: R
authors.lastname: Oystese
authors.forename: M J
authors.initials: MJ
authors.lastname: Hamers
authors.forename: O P
authors.initials: OP
authors.lastname: Veiby
authors.forename: T
authors.initials: T
authors.lastname: Rolfsen
authors.forename: R W
authors.initials: RW
authors.lastname: Stephens
authors.forename: K S
authors.initials: KS
authors.lastname: Sakariassen
mesh_terms: D001777:Blood Coagulation; D001779:Blood Coagulation Factors / Q000378:metabolism*; D001026:Coronary Artery Bypass; D005112:Extracorporeal Circulation; D005260:Female; D006493:Heparin / Q000627:therapeutic use*; D006801:Humans; D008070:Lipopolysaccharides / Q000378:metabolism; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D009204:Myocardial Revascularization; D013925:Thromboplastin / Q000378:metabolism*
chemical_list: D001779:Blood Coagulation Factors; D008070:Lipopolysaccharides; C045071:leukocyte procoagulant activity; D006493:Heparin; D013925:Thromboplastin