Study on the Effect of Streptokinase-Activated Plasmin (Fibrinolysin) on Clots in Various Stages of Organization12

The Lysis of Artificially Induced Intravascular Clots in Man by Intravenous Infusions of Streptokinase*†

“…The experimental data presented here, although limited, strongly suggest that 48 hour clots are initially more difficult to lyse and reform more rapidly than 24 hour clots, and are therefore in basic agreement with the studies of Back, Ambrus, Simpson and Shulman (37).…”

Deep vein thrombosis

“…Although the susceptibility of thrombi to lysis probably decreases with the age of the thrombus (Back et al, 1958), it is of interest and contrary to expectation that in venous thrombo-embolism the age of the thrombus is not invariably critical and that lysis of relatively old thrombi may be obtained. The incidence of re-thrombosis at the present time probably obviates the use of the drug in early cases of iliofemoral thrombosis where venous thrombectomy is so effective.…”

Treatment of experimental pulmonary embolism by main pulmonary arterial infusion of a fibrinolytic agent

“…Dogs belonging to'groups 2 and 3 were sacrificed while receiving the last few millilitres of the Thrombolysin solution. Previous studies (Back, Ambrus, Simpson, and Shulman, 1958) have shown that, after lysis of acute clots, refor.mation was observed in spite of continued treatment with plasmin. These authors attributed this phenomenon to some degree of trauma to the At the fourth hour this graph emphasizes the difference between group 3 animals (Local THR) and groups 1 and 2. vascular walls.…”