Treatment of experimental venous thrombosis with streptokinase and ancrod (Arvin)

Abstract
Phenol was applied to the exposed femoral veins of anaesthetized dogs and the fate of the induced thrombi was followed by serial phlebography and eventual histology. Thrombi less than 24 hours old were treated with a 9-hour infusion of streptokinase and patency was restored in 38 of 48 veins (79 percent). Rethrombosis had occurred 6 days later in all of 10 veins which received no further treatment. Five of 14 veins (36 per cent) remained patent when dogs were given treatment with ancrod following thrombolysis by streptokinase. Probable explanations for rethrombosis in the other 9 veins despite ancrod therapy were failure to clear the veins completely of thrombi with streptokinase and failure to maintain a sufficiently low level of plasma fibrinogen in some dogs because of bleeding. Streptokinase therapy followed by ancrod warrants further study in the treatment of deep-vein thrombosis.