The sequelae of thrombus formation, both by shear forces and by collagen fiber, the subsequent coagulation, and the dislodgement of thrombi (thromboly sis) were measured from a small volume of nonanticoagulated blood sample, by a new instrument. Addition of streptokinase (SK) or tissue-type plasminogen activator (rt-PA) to the blood sample eliminated the need for anticoagulation for thrombolysis measurement: clot lysis preceded and allowed thrombolysis to occur. The test revealed activation of platelets and coagulation by SK and rt-PA. Apart from this general trend, platelet reactivity in response to plasminogen activator showed great individual variation. Whether the greatly enhanced (42 %) or prolonged hemostasis (13%), observed in different blood samples with rt-PA, could be used as a predictor of reocclusion or bleeding complications remains to be established. Thrombolysis did not occur in 12 % of the samples tested. These thrombolysis models may be useful for developing new agents for the dissolution of platelet-rich thrombi. It is suggested that this technique be used for monitoring thrombolytic therapy. © 1990, Sage Publications. All rights reserved.
