title: The effect of pre-hospital glycoprotein IIb-IIIa inhibitors on angiographic outcome in STEMI patients who are candidates for primary PCI.
abstract: OBJECTIVE
  Aim of this study was to assess the effect of early initiation of high bolus dose tirofiban on top of dual antiplatelet therapy on angiographic outcome before and after primary percutaneous coronary intervention (PCI) in ST-elevation myocardial infraction patients.
  
  
  BACKGROUND
  Glycoprotein IIb/IIIa inhibitors are effective inhibitors of platelet aggregation, and have shown to reduce thrombotic complications in patients undergoing PCI.
  
  
  METHODS
  This is a pre-specified angiographic analysis of the On-TIME 2 trial (N = 984) and its open label run-in phase (N = 414). All angiographic parameters, including quantitative coronary angiography (QCA) were performed in an independent angiographic core lab.
  
  
  RESULTS
  Of the 1,398 patients, 709 patients (50.7%) were randomized to pre-hospital tirofiban. An open infarct related vessel (TIMI 2 or 3 flow) at initial angiography was more often present in the tirofiban group as compared to the no tirofiban group (58.3% vs. 49.7%, P = 0.002). Tirofiban also reduced initial thrombus burden (P for trend = 0.035) as well as thrombus grade 5 (46.9% vs. 54.3%, P = 0.016) and showed a trend toward a reduction in large thrombus burden (LTB) (69.4% vs. 74.5%, P = 0.055). After PCI, a trend towards a lower corrected TIMI frame count (cTFC) in the tirofiban group was found. A significant interaction was found with time of initiation of study drug, with highest efficacy of tirofiban when given within 76 min after symptom onset, with a significantly lower cTFC after PCI (21.9 ± 17.6 vs. 23.9 ± 18.5, P = 0.008, P for interaction P = 0.006).
  
  
  CONCLUSIONS
  In patients undergoing primary PCI, pre-hospital administration of tirofiban reduces initial thrombus burden and improves initial patency of the infarct related vessel before PCI. Initiation of tirofiban seems to be most effective when given very early after the onset of symptoms; however, this finding needs confirmation in other studies.
  
  
  BACKGROUND
  The On-TIME 2 trial is registered, at http://isrctn.org, number ISRCTN06195297.
authors.affiliation: Isala klinieken, Zwolle, The Netherlands.
authors.forename: Renicus S
authors.initials: RS
authors.lastname: Hermanides
authors.forename: J Wouter
authors.initials: JW
authors.lastname: van Werkum
authors.forename: Jan Paul
authors.initials: JP
authors.lastname: Ottervanger
authors.forename: Nicoline J
authors.initials: NJ
authors.lastname: Breet
authors.forename: A T Marcel
authors.initials: AT
authors.lastname: Gosselink
authors.forename: K Gert
authors.initials: KG
authors.lastname: van Houwelingen
authors.forename: Jan-Henk E
authors.initials: JH
authors.lastname: Dambrink
authors.forename: Christian
authors.initials: C
authors.lastname: Hamm
authors.forename: Jurrien M
authors.initials: JM
authors.lastname: ten Berg
authors.forename: Arnoud W J
authors.initials: AW
authors.lastname: van 't Hof
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects; D001241:Aspirin / Q000008:administration & dosage; D000077144:Clopidogrel; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000187:drug effects; D003328:Coronary Thrombosis / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology / Q000628:therapy*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology / Q000628:therapy*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012720:Severity of Illness Index; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D013997:Time Factors; D000077466:Tirofiban; D016896:Treatment Outcome; D014443:Tyrosine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D014654:Vascular Patency / Q000187:drug effects
chemical_list: D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D014443:Tyrosine; D000077144:Clopidogrel; D000077466:Tirofiban; D013988:Ticlopidine; D001241:Aspirin