title: Platelet inhibition by abciximab bolus-only administration and oral ADP receptor antagonist loading in acute coronary syndrome patients: the blocking and bridging strategy.
abstract: BACKGROUND
  Current guidelines still recommend the bolus and infusion administration of glycoprotein IIbIIIa inhibitors in patients with high-risk acute coronary syndrome undergoing percutaneous coronary intervention. We sought to evaluate the extent of platelet inhibition by a blocking and bridging strategy with intracoronary abciximab bolus-only administration and oral loading of adenosine diphosphate receptor antagonists.
  
  
  METHODS
  Fifty-six consecutive high-risk acute coronary syndrome patients with bolus-only abciximab administration (0.25 mg/kg i.c.) and loading with 600 mg clopidogrel (55%) or 60 mg prasugrel (45%) were included in this study. Platelet aggregation induced by thrombin receptor-activating peptide and adenosine diphosphate was measured by multiple electrode aggregometry up to 7 days.
  
  
  RESULTS
  Thrombin receptor-activating peptide induced platelet aggregation was significantly suppressed for a minimum of 48 h (45±17U) and returned to a normal range (>84 U) after 6 days (90±26U; p<0.001). Co-medication with prasugrel significantly reduced adenosine diphosphate-induced (p=0.002) and thrombin receptor-activating peptide-induced (p=0.02) platelet aggregation compared with clopidogrel throughout the observation period. No stent thrombosis or repeat myocardial infarction occurred at 30-day follow-up.
  
  
  CONCLUSIONS
  Immediate blocking of platelet aggregation in high-risk acute coronary syndrome patients by intracoronary abciximab bolus-only administration and bridging to prolonged inhibition via oral blockade of ADP receptors effectively inhibited overall platelet reactivity for at least 48 h, questioning the value of continuous abciximab infusion. Co-medication with prasugrel vs. clopidogrel synergistically augmented platelet inhibition.
authors.affiliation: 5th Medical Department with Cardiology, Kaiser Franz Josef Hospital, Vienna, Austria. guenter.christ@wienkav.at
authors.forename: Günter
authors.initials: G
authors.lastname: Christ
authors.forename: Thomas
authors.initials: T
authors.lastname: Hafner
authors.forename: Jolanta M
authors.initials: JM
authors.lastname: Siller-Matula
authors.forename: Marcel
authors.initials: M
authors.lastname: Francesconi
authors.forename: Katharina
authors.initials: K
authors.lastname: Grohs
authors.forename: Eva
authors.initials: E
authors.lastname: Wilhelm
authors.forename: Andrea
authors.initials: A
authors.lastname: Podczeck-Schweighofer
mesh_terms: D000077284:Abciximab; D054058:Acute Coronary Syndrome / Q000188:drug therapy*; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000627:therapeutic use; D001792:Blood Platelets; D000077144:Clopidogrel; D004333:Drug Administration Routes; D005260:Female; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000008:administration & dosage* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage* / Q000627:therapeutic use; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000627:therapeutic use; D010979:Platelet Function Tests; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors; D000068799:Prasugrel Hydrochloride; D058921:Purinergic P2Y Receptor Antagonists / Q000008:administration & dosage* / Q000627:therapeutic use; D013876:Thiophenes / Q000008:administration & dosage* / Q000627:therapeutic use; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D000911:Antibodies, Monoclonal; D007140:Immunoglobulin Fab Fragments; D010879:Piperazines; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D058921:Purinergic P2Y Receptor Antagonists; D013876:Thiophenes; D000077144:Clopidogrel; D000068799:Prasugrel Hydrochloride; D013988:Ticlopidine; D000077284:Abciximab
keywords: ACS; ADP; Abciximab; Dual antiplatelet therapy; GPI; MEA; NSTEMI; Non-ST-elevation myocardial infarction; PCI; Platelet function; Primary percutaneous coronary intervention; ST-elevation myocardial infarction; STEMI; TRAP; Thrombin receptor-activating peptide; acute coronary syndrome; adenosine diphosphate; glycoprotein IIb/IIIa receptor inhibitor; multiple electrode aggregometry; percutaneous coronary intervention