title: Circulating endothelial cells demonstrate an attenuation of endothelial damage by minimizing the extracorporeal circulation.
abstract: OBJECTIVE
  Detachment of endothelial cells may represent serious injury of the endothelium after cardiopulmonary bypass. We investigated whether the extent of endothelial injury is related to the type of cardiopulmonary bypass system used (conventional or minimized) and determined circulating endothelial cells as well as von Willebrand factor and soluble thrombomodulin.
  
  
  METHODS
  Twenty patients scheduled for elective coronary bypass grafting were randomly assigned to either the minimal extracorporeal circulation system or the standard cardiopulmonary bypass. Ten healthy volunteers served as controls. Circulating endothelial cells per milliliter of full blood were perioperatively determined by immunomagnetic cell separation technique. Endothelial plasma markers were measured by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Preoperative circulating endothelial cell numbers did not differ between the experimental groups, but were significantly higher than in the healthy controls (18.6 +/- 5.6 vs 7.2 +/- 3.8, P < .001). At 6 hours, circulating endothelial cell numbers increased significantly compared with baseline in both experimental groups and peaked at 12 hours after cardiopulmonary bypass initiation, each time with significantly lower values in the minimal extracorporeal circulation group (6 hours: 44.0 +/- 9.9 vs 29.6 +/- 9.8, P = .007; 12 hours: 48.1 +/- 6.8 vs 31.8 +/- 7.1, P < .001). Likewise, von Willebrand factor and soluble thrombomodulin postoperatively increased in both groups with a tendency toward lower levels in the minimal extracorporeal circulation group. Although circulating endothelial cells gradually declined, continually with lower numbers in the minimal extracorporeal circulation group, the endothelial plasma markers remained elevated during observation time.
  
  
  CONCLUSIONS
  Circulating endothelial cells represent a novel marker of the intrinsic endothelial damage caused by cardiopulmonary bypass. Its analysis facilitates the evaluation of cardiopulmonary bypass modifications as the minimal extracorporeal circulation system could be proven to be less injurious to endothelium and myocardium.
authors.affiliation: Department of Cardiac Surgery, University of Rostock, Rostock, Germany. cskrabal@fastmail.fm
authors.forename: Christian A
authors.initials: CA
authors.lastname: Skrabal
authors.forename: Yeong H
authors.initials: YH
authors.lastname: Choi
authors.forename: Alexander
authors.initials: A
authors.lastname: Kaminski
authors.forename: Michael
authors.initials: M
authors.lastname: Steiner
authors.forename: Guenther
authors.initials: G
authors.lastname: Kundt
authors.forename: Gustav
authors.initials: G
authors.lastname: Steinhoff
authors.forename: Andreas
authors.initials: A
authors.lastname: Liebold
mesh_terms: D000368:Aged; D015415:Biomarkers; D002315:Cardiopulmonary Bypass / Q000379:methods; D002318:Cardiovascular Diseases / Q000097:blood / Q000601:surgery; D002452:Cell Count; D002469:Cell Separation; D042783:Endothelial Cells / Q000473:pathology / Q000502:physiology*; D004730:Endothelium, Vascular / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D018180:Thrombomodulin / Q000097:blood; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D015415:Biomarkers; D018180:Thrombomodulin; D014841:von Willebrand Factor