title: Randomized comparison of platelet-leukocyte aggregates and platelet activation in blood: heparin-coated coiled wire stent implantation versus balloon angioplasty in acute myocardial infarction.
abstract: BACKGROUND
  Stent implantation has been shown to be superior to balloon angioplasty in patients with acute myocardial infarction (AMI). Newer trials indicate that platelet-leukocyte aggregates are a more sensitive marker for platelet activation than platelet surface marker. Our study examined platelet activation and platelet-leukocyte interaction in blood in patients with AMI randomized to heparin-coated stent implantation versus balloon angioplasty.
  
  
  METHODS
  Forty-seven patients with AMI were included into our study. Patients were randomized to heparin-coated stent implantation (n=31) or balloon angioplasty (n=16). Platelet activation, total platelet-leukocyte aggregates and aggregate composition in blood were assessed by flow cytometry before, immediately after and 24 h after intervention.
  
  
  RESULTS
  No differences in platelet activation, total platelet-leukocyte aggregates and aggregate composition were found between both groups before intervention. Immediately after intervention, platelet activation was comparably increased in both groups. Patients treated with heparin-coated stent showed a decrease in total platelet-leukocyte aggregates 24 h after intervention (3.9% [2.8; 4.7] versus 3.2% [2.4; 4.1]; p<0.01). Platelet-monocyte conjugates decreased 24 h after heparin-coated stent implantation compared to balloon angioplasty alone (0.28% [0.17; 0.42] versus 0.49% [0.45; 0.79]; p<0.05). No difference in total platelet-leukocyte aggregates was found in patients treated with balloon angioplasty alone.
  
  
  CONCLUSIONS
  An inhibitory effect of heparin-coated stent implantation on total platelet-leukocyte aggregates and platelet-monocyte conjugates in blood was demonstrated in patients with AMI. This reflects heparin-coated stent implantation to be less thrombogenic than balloon angioplasty alone.
authors.affiliation: Department of Cardiology, Charité-Universitymedicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Jaster
authors.forename: Peter
authors.initials: P
authors.lastname: Schwimmbeck
authors.forename: Sebastian
authors.initials: S
authors.lastname: Spencker
authors.forename: Heinz-Peter
authors.initials: HP
authors.lastname: Schultheiss
authors.forename: Ursula
authors.initials: U
authors.lastname: Rauch
mesh_terms: D000368:Aged; D000800:Angioplasty, Balloon / Q000009:adverse effects*; D001792:Blood Platelets / Q000473:pathology; D002448:Cell Adhesion; D020099:Coated Materials, Biocompatible; D005260:Female; D005434:Flow Cytometry; D006493:Heparin / Q000627:therapeutic use; D006801:Humans; D007962:Leukocytes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000628:therapy*; D015539:Platelet Activation; D019919:Prosthesis Implantation / Q000009:adverse effects; D015607:Stents / Q000009:adverse effects*
chemical_list: D020099:Coated Materials, Biocompatible; D006493:Heparin