title: Long-lasting depression of the factor XII-dependent fibrinolytic system in patients with myocardial infarction undergoing thrombolytic therapy with recombinant tissue-type plasminogen activator: a randomized placebo-controlled study.
abstract: In a randomized placebo-controlled study, seven patients with acute myocardial infarction allocated to intravenous treatment with 100 mg of recombinant tissue-type plasminogen activator (rt-PA) and seven patients allocated to placebo were studied during eight sampling periods before and after treatment. Seven patients with acute myocardial infarction treated intravenously with 1.5 million U of streptokinase were later studied during two sampling periods before and after treatment. The placebo group showed no significant deviations of endogenous factor XII-dependent fibrinolytic activity (p greater than 0.05). In the rt-PA group, this activity decreased significantly (p less than 0.001) after the infusion and remained depressed throughout the 1st 4 days. A significant decrease in activity (p less than 0.05) was also found in the streptokinase-treated patients. The depletion of factor XII-dependent fibrinolytic activity was not due to generation of inhibition or a depletion of factor XII, prekallikrein and plasminogen, but could be related to the proactivator of this system. It is concluded that rt-PA (and streptokinase) treatment in patients with acute myocardial infarction causes a prolonged depletion of factor XII-dependent fibrinolytic activity. This depression of endogenous fibrinolytic activity needs to be evaluated in relation to the enhanced risk of coronary reocclusion after thrombolytic therapy.
authors.affiliation: Department of Clinical Chemistry, Ribe County Hospital, Esbjerg, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Munkvad
authors.forename: J
authors.initials: J
authors.lastname: Jespersen
authors.forename: J
authors.initials: J
authors.lastname: Gram
authors.forename: C
authors.initials: C
authors.lastname: Kluft
mesh_terms: D003864:Depression, Chemical; D004311:Double-Blind Method; D005174:Factor XII / Q000187:drug effects* / Q000502:physiology; D005342:Fibrinolysis / Q000187:drug effects*; D006801:Humans; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000188:drug therapy*; D011994:Recombinant Proteins / Q000627:therapeutic use; D013300:Streptokinase / Q000627:therapeutic use; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014568:Urokinase-Type Plasminogen Activator / Q000502:physiology
chemical_list: D011994:Recombinant Proteins; D005174:Factor XII; D013300:Streptokinase; D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator