Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter-Directed Thrombolysis

Activase, the study drug, is a fibrinolytic drug that is indicated for use in acute myocardial infarction, acute ischemic stroke, and acute massive pulmonary embolism in adults. Previous studies have established the ability of rt-PA to lyse venous thrombus in patients with deep vein thrombosis (DVT), and suggest that successful rt-PA mediated thrombolysis can prevent the post-thrombotic syndrome (PTS), a morbid, late complication of DVT that occurs in nearly 50% of patients. rt-PA is delivered directly into venous thrombus using a catheter/device which is embedded within the thrombus by a physician under imaging guidance. This method of rt-PA delivery, pharmacomechanical catheter-directed intrathrombus thrombolysis (PCDT),is thought to be safer, more effective, and more efficient than previous methods. The question of whether PCDT using rt-PA improves long-term DVT patient outcomes with acceptable risk and cost has not yet been addressed. The rationale for performing the ATTRACT Trial is based upon: * the major burden of PTS on DVT patients and the U.S. healthcare system * the association between rapid clot lysis and prevention of PTS * the proven ability of rt-PA to dissolve venous thrombus in proximal DVT * recent advances in CDT methods which may lower bleeding risk * the major clinical controversy on whether CDT should be routinely used for first-line DVT therapy