Thrombolysis is the breakdown (lysis) of blood clots by pharmacological means, and commonly called clot busting. It works by stimulating secondary fibrinolysis by plasmin through infusion of analogs of tissue plasminogen activator (tPA), the protein that normally activates plasmin. recent multicenter randomized trial (DUET) compared standard catheter-directed thrombolysis (CDT) versus ultrasound-accelerated thrombolysis (USAT, EKOS Corporation) for the treatment of acute peripheral arterial thrombotic occlusions.