Mechanism of Rethrombosis After Thrombolytic Therapy: Angioscopic Findings and Investigation of the Coagulation System in Dogs

The purpose of this study was to angioscopically observe the process of thrombolysis after intracoronary administration of thrombolytic agents and to investigate the effects of these agents on coagulation/fibrinolysis systems in dogs. The coronary endothelium was removed and thrombus formation was confirmed by angioscopy. In the tissue plas minogen activator (tPA) group (n=8), complete thrombolysis occurred in all animals, but thrombolysis was incomplete in the urokinase (UK) group (n=6). The plasma level of plasmin α2-plasmin inhibitor complex peaked at 15 minutes after treatment in both the tPA and UK groups. Plasma thrombin-antithrombin III (TAT) complex decreased tran siently at 15 minutes after tPA administration but increased at 30 and 60 minutes (P