BEYOND THROMBOLYSIS - OTHER EFFECTS OF THROMBOLYTIC DRUGS

OBJECTIVE: To review the effects of plasminogen activators (tissue pla sminogen activator, streptokinase, and anistreplase) on fibrinogen and thrombin, platelets, complement, blood rheology, and neutrophils. DAT A SOURCES: A MEDLINE search, as well as a review of recent scientific abstracts, was conducted to identify pertinent literature. STUDY SELEC TION: Focus was placed on studies conducted in humans. However, many i n vitro studies have been performed to fully elucidate the effect of p lasminogen activators on different aspects of hemostasis and on the fi brinolytic and immune systems. DATA EXTRACTION: Data from in vitro, hu man, and animal studies were evaluated.DATA SYNTHESIS: There is a disc repancy between 90-minute patency and mortality in acute myocardial in farction patients treated with thrombolytic drugs. This could be cause d, in part, by other hematologic and immunologic effects of thrombolyt ic drugs. Though the emphasis of clinical trials has been infarct-rela ted artery patency, left ventricular function, and mortality, some stu dies have evaluated the effect of thrombolytic agents on fibrinogen an d thrombin, platelets, blood rheology, complement, and neutrophils. Th is review discusses the alteration of systemic hematologic and immunol ogic parameters by thrombolytic drugs and the possible clinical implic ations of these effects. CONCLUSIONS: Although the interactions betwee n thrombolytic drugs, hemostasis, and the fibrinolytic and immune syst ems are complex and still not fully understood, it appears that these drugs differ in their effects on these systems. A greater understandin g of these properties and their clinical implications may ultimately e nhance the care and outcome of acute myocardial infarction patients tr eated with thrombolytic therapy.