PEERLESS Trial

The PEERLESS randomized controlled trial compared large-bore mechanical thrombectomy (LBMT) and catheter-directed thrombolysis (CDT) in managing intermediate-risk pulmonary embolism (PE). Enrolling 550 patients, the study assessed a primary composite endpoint through a win ratio approach, evaluating all-cause mortality, intracranial hemorrhage, major bleeding, clinical deterioration, and post-procedural ICU admission or stay length. LBMT showed a significantly lower occurrence of the primary endpoint compared to CDT (win ratio = 5.01; 95% CI: 3.68–6.97; P<0.001).

Key outcomes included reduced rates of clinical deterioration and ICU utilization for LBMT, with fewer ICU admissions (41.6% vs. 98.6%) and shorter stays (>24 hours in 19.3% vs. 64.5% for CDT). While both treatments had similar rates of mortality and major bleeding, LBMT patients experienced better respiratory metrics and shorter hospital stays (4.5 vs. 5.3 days; P=0.002)​.