Development of catheter-directed intrathrombus thrombolysis with plasmin for the treatment of acute lower extremity arterial occlusion

Catheter-directed thrombolysis is an important treatment option for many patients with acute lower extremity ischemia due to arterial and/or graft thrombosis. A growing body of evidence demonstrates that thrombolytic therapy for acute limb ischemia reduces the need for amputation; however, bleeding complications are more likely with lytic therapy. New direct-acting fibrinolytic compounds are being developed that facilitate thrombolysis while reducing the risk of bleeding. Plasmin, the active enzyme produced by all plasminogen activators, works directly upon thrombus and is neutralized instantly in the systemic circulation. This report reviews the principles for effective catheter directed thrombolysis for acute arterial occlusions and describes the development and evaluation of the new thrombolytic, plasmin.