Thrombelastographic patterns produced by fibrinolytic agents incorporated in fibrin

¹ James F. Mitchell Foundation, Institute for Medical Research, Washington, D. C.

Lysis of clots produced from bovine fibrinogen and bovine thrombin in the presence of fibrinolytic agents was followed by thrombelastography in order to obtain information about the mechanism of clot lysis in a standardized, purified system, which simulated physiological clot lysis. A characteristic difference in the thrombelastographic patterns was found between lysis of clots produced by preformed plasmin and by activators of plasminogen. With activator plasmin formation occurred at a late stage of the total period of clot lysis; plasmin was then produced in large quantities and the resulting lysis was extremely rapid. A correlation curve between concentration and lysis time yielded in all instances a straight line in a double logarithmic graph. There was a characteristic difference between the slopes obtained with plasmin and with activator, indicating different mechanisms of reaction.

Key Words: fibrinolysis • plasmin • plasminogen activator • urokinase • streptokinase • thrombolysis • thrombelastography

Submitted on July 29, 1964