title: Effect of heparin on coronary arterial patency after thrombolysis with tissue plasminogen activator in acute myocardial infarction.
abstract: Infarct artery patency rates at 90 minutes after coronary thrombolysis using recombinant tissue-type plasminogen activator (rt-PA) with and without concurrent heparin anticoagulation have been shown to be comparable. The contribution of heparin to efficacy and safety after thrombolysis with rt-PA is unknown. In this pilot study, 84 patients were treated within 6 hours of onset of acute myocardial infarction (mean of 2.7 hours) with the standard dose of 100 mg of rt-PA over 3 hours. Forty-two patients were randomized to receive additionally immediate intravenous heparin anticoagulation (5,000 U of intravenous bolus followed by 1,000 U/hour titrated to a partial thromboplastin time of 1.5 to 2.0 times control) while 42 patients received rt-PA alone. Coronary angiography performed on day 3 (48 to 72 hours, mean 57) after rt-PA therapy revealed infarct artery patency rates of 71 and 43% in anticoagulated and control patients, respectively (p = 0.015). Recurrent ischemia or infarction, or both, occurred in 3 (7.1%) anticoagulated patients and 5 (11.9%) control patients (difference not significant). Mild, moderate and severe bleeding occurred in 52, 10 and 2% of the group receiving anticoagulation, respectively, and 34, 2 and 0% of patients in the control group, respectively (p = 0.006). These data indicate that after rt-PA therapy of acute myocardial infarction, heparin therapy is associated with substantially higher coronary patency rates 3 days after thrombolysis but is accompanied by an increased incidence of minor bleeding complications.
authors.affiliation: Division of Cardiology, Tulane University Medical Center, New Orleans, Louisiana.
authors.forename: S D
authors.initials: SD
authors.lastname: Bleich
authors.forename: T C
authors.initials: TC
authors.lastname: Nichols
authors.forename: R R
authors.initials: RR
authors.lastname: Schumacher
authors.forename: D H
authors.initials: DH
authors.lastname: Cooke
authors.forename: D A
authors.initials: DA
authors.lastname: Tate
authors.forename: S L
authors.initials: SL
authors.lastname: Teichman
mesh_terms: D017023:Coronary Angiography; D003331:Coronary Vessels / Q000187:drug effects*; D005260:Female; D006493:Heparin / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy*; D010865:Pilot Projects; D015912:Thrombolytic Therapy; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014654:Vascular Patency / Q000187:drug effects
chemical_list: D006493:Heparin; D010959:Tissue Plasminogen Activator