47-year-old female with a history of Antiphospholipid antibody syndrome who has been non compliant with warfarin presents with deep vein thrombosis and dyspnea. She is hypotensive and tachypneic.CT of chest shows a saddle embolus. She does not respond to heparin and fluids. Echocardiogram shows RV hypokinesis. Which of the following is appropriate management?