Fibrinogen Levels and Bleeding Risk in Patients Undergoing Ultrasound-Assisted Catheter-Directed Thrombolysis for Submassive Pulmonary Embolism.

OBJECTIVES We sought to test the hypothesis that patients undergoing ultrasound-assisted catheter-directed thrombolysis (USAT) with standard alteplase and heparin dosing would not develop significant depletion of systemic fibrinogen, which may account for the lower risk of bleeding seen in contemporary trials. We also sought to compare the relative outcomes of individuals with submassive pulmonary embolism (PE) undergoing USAT and...