A Prospective, Single-arm, Multi-center Trial of EkoSonic® Endovascular System and Activase for Treatment of Acute Pulmonary Embolism (PE).

Inclusion Criteria:

- CT evidence of proximal PE (filling defect in at least one main or segmental
pulmonary artery) AND

- Age ≥ 18 years AND

- PE symptom duration ≤14 days AND

- Informed consent can be obtained from subject or Legally Authorized Representative
(LAR) AND

- Massive PE (syncope, systemic arterial hypotension, cardiogenic shock, or
resuscitated cardiac arrest) OR

- Submassive PE (RV diameter-to-LV diameter ≥ 0.9 on contrast-enhanced chest CT)

Exclusion Criteria:

- Stroke or transient ischemic attack (TIA), head trauma, or other active intracranial
or intraspinal disease within one year

- Recent (within one month) or active bleeding from a major organ

- Hematocrit < 30%

- Platelets < 100 thousand/μL

- INR > 3

- aPTT > 50 seconds on no anticoagulants

- Major surgery within seven days

- Serum creatinine > 2 mg/dL

- Clinician deems high-risk for catastrophic bleeding

- History of heparin-induced thrombocytopenia (HIT)

- Pregnancy

- Catheter-based pharmacomechanical treatment for pulmonary embolism within 3 days of
study enrollment

- Systolic blood pressure less than 80 mm Hg despite vasopressor or inotropic support

- Cardiac arrest (including pulseless electrical activity and asystole) requiring
active cardiopulmonary resuscitation (CPR)

- Evidence of irreversible neurological compromise

- Life expectancy < 30 days

- Use of thrombolytics or glycoprotein IIb/IIIa antagonists within 3 days prior to
inclusion in the study

- Previous enrollment in the SEATTLE study