PEERLESS II: RCT of FlowTriever vs. Anticoagulation Alone in Pulmonary Embolism


This study is a prospective, multicenter, randomized controlled trial of the FlowTriever System plus anticoagulation compared to anticoagulation alone for intermediate-risk acute PE.

Study Arms

  • Active Comparator: FlowTriever
  • Active Comparator: Anticoagulant 


  1. Age at enrollment ≥ 18 years
  2. Objective evidence of a proximal filling defect in at least one main or lobar pulmonary artery, as confirmed by CTPA, pulmonary angiography, or other imaging modality
  3. RV dysfunction, as defined as one or more of the following: RV/LV ratio ≥ 0.9 or RV dilation or hypokinesis
  4. At least two additional risk factors, identified by at least one measure in two separate categories noted below:
    1. Hemodynamic: i. SBP 90-100mmHg ii. Resting heart rate > 100 bpm
    2. Biomarker: i. Elevated* cardiac troponin (troponin I or troponin T, conventional or high sensitivity) ii. Elevated* BNP or NT-proBNP iii. Elevated venous lactate ≥2 mmol/L * Elevated, meaning at or above the upper limit of normal, per local standards for the assay used
    3. Respiratory: i. O2 saturation < 90% on room air ii. Supplemental O2 requirement ≥ 4 L/min iii. Respiratory rate ≥ 20 breaths/min iv. mMRC score > 0
  5. Symptom onset within 14 days of confirmed PE diagnosis
  6. Willing and able to provide informed consent