title: Efficacy of 100 mg of double-bolus alteplase in achieving complete perfusion in the treatment of acute myocardial infarction.
abstract: OBJECTIVE
  The purpose of this study was to assess the efficacy of 150 mg of aspirin plus 100 mg of alteplase, administered as two intravenous bolus injections of 50 mg each given 30 min apart, and followed by intravenous heparin, on infarct-related coronary artery patency (Thrombolysis in Myocardial Infarction [TIMI] flow grade 3).
  
  
  BACKGROUND
  Previous workers have shown in animals that reducing the duration of an infusion of recombinant tissue-type plasminogen activator increases the initial rate of thrombolysis, resulting in high early infarct-related coronary artery patency rates. The logical progression of this idea is bolus administration.
  
  
  METHODS
  Consecutive patients presenting up to 6 h from the onset of symptoms were recruited for the study. Angiography was performed at 60 and 90 min after the first bolus and between 19 to 48 h after study entry. Patients were followed up for 1 month.
  
  
  RESULTS
  At 60 min, angiography revealed infarct-related coronary artery patency of TIMI flow grade 3 in 55 (86%) of 64 patients (95% confidence interval [CI] 75% to 93%) and TIMI flow grade 2 or 3 in 58 (91%) of 64 patients (95% CI 81% to 97%). At 90 min, infarct-related artery patency of TIMI flow grade 3 was achieved in 74 (88%) of 84 patients (95% CI 79% to 94%) and TIMI flow grade 2 or 3 in 78 (93%) of 84 patients (95% CI 85% to 97%). Two patients (2.4%) had early angiographic reocclusion whereas 10 (11.9%) had late reinfarction. Bleeding episodes were mostly minor, and there was no cerebrovascular bleeding. Five patients (6.0%) died within 1 month of the acute myocardial infarction.
  
  
  CONCLUSIONS
  In 84 patients with acute myocardial infarction, administration of 100 mg of double-bolus (2 x 50 mg) alteplase, aspirin and heparin is associated with remarkably high early infarct-related coronary artery patency rates (TIMI flow grade 3) of 86% and 88%, respectively, at 60 and 90 min.
authors.affiliation: Regional Medical Cardiology Centre, Royal Victoria Hospital, Belfast, Northern Ireland, United Kingdom.
authors.forename: J A
authors.initials: JA
authors.lastname: Purvis
authors.forename: A J
authors.initials: AJ
authors.lastname: McNeill
authors.forename: R A
authors.initials: RA
authors.lastname: Siddiqui
authors.forename: M J
authors.initials: MJ
authors.lastname: Roberts
authors.forename: B M
authors.initials: BM
authors.lastname: McClements
authors.forename: D
authors.initials: D
authors.lastname: McEneaney
authors.forename: N P
authors.initials: NP
authors.lastname: Campbell
authors.forename: M M
authors.initials: MM
authors.lastname: Khan
authors.forename: S W
authors.initials: SW
authors.lastname: Webb
authors.forename: C M
authors.initials: CM
authors.lastname: Wilson
mesh_terms: D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D010865:Pilot Projects; D011446:Prospective Studies; D015912:Thrombolytic Therapy / Q000009:adverse effects / Q000379:methods*; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage* / Q000627:therapeutic use; D014654:Vascular Patency / Q000187:drug effects*
chemical_list: D010959:Tissue Plasminogen Activator