Ultrasound-Facilitated, Catheter-Directed Fibrinolysis for Acute Pulmonary Embolism

Whether anticoagulation alone is an adequate treatment for acute, intermediate-risk pulmonary embolism is uncertain.

We conducted a multinational, adaptive-design trial with blinded outcome adjudication. Patients with intermediate-risk pulmonary embolism (with a ratio of right ventricular end-diastolic diameter to left ventricular end-diastolic diameter of ≥1.0 and an elevated troponin level) were eligible if they had at least two indicators of cardiorespiratory distress (systolic blood pressure of ≤110 mm Hg, a heart rate of ≥100 beats per minute, or a respiratory rate of >20 breaths per minute). Patients were randomly assigned to undergo ultrasound-facilitated, catheter-directed fibrinolysis with alteplase plus anticoagulation (the intervention group) or anticoagulation alone (the control group) according to prespecified treatment protocols. The primary outcome was a composite of pulmonary embolism-related death, cardiorespiratory decompensation or collapse, or symptomatic recurrence of pulmonary embolism within 7 days.