title: Hypercoagulability and platelet inhibition after OPCAB. Randomized intervention with clopidogrel.
abstract: OBJECTIVE
  Data on graft patency after Off-Pump Coronary Artery Bypass (OPCAB) suggest that the incidence of early graft closure is not increased compared to conventional coronary artery bypass surgery. However, hypercoagulability following OPCAB is still of concern, and acetylsalicylic acid as thromboembolic prophylaxis might be insufficient in the first weeks following OPCAB surgery.
  
  
  METHODS
  Twenty nine patients were randomly assigned to+/- 75 mg of clopidogrel until 30 days after OPCAB surgery. The follow-up time was 2 months including standard blood samples and thrombelastography (TEG) with a specific platelet inhibition assay, which was evaluated as a part of the study.
  
  
  RESULTS
  In both groups a significant increase in TEG maximum amplitude was found 5 days after surgery. Platelet inhibition showed great variations but was significantly increased in the clopidogrel group (34.1%) vs. control group (11.0%) after 1 month.
  
  
  CONCLUSIONS
  Hypercoagulability was seen 5 days after OPCAB and could not be demonstrated after 1 month. No clinical effects of the hypercoagulability were observed, and further research is needed to determine if clopidogrel should be recommended after OPCAB.
authors.affiliation: Department of Cardiothoracic Surgery, Rigshospitalet, Copenhagen University Hospital, Denmark. allan@bybeck.dk
authors.forename: Allan Bybeck
authors.initials: AB
authors.lastname: Nielsen
authors.forename: Louise
authors.initials: L
authors.lastname: Bochsen
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Steinbrüchel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000494:pharmacology*; D000077144:Clopidogrel; D047549:Coronary Artery Bypass, Off-Pump; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D011446:Prospective Studies; D013916:Thrombelastography; D013923:Thromboembolism; D019851:Thrombophilia; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine