Evaluation of Catheter-Directed Thrombolysis Device Type and Dosing on Treatment Outcomes in Intermediate-Risk Pulmonary Embolism: A PEERLESS Randomized Controlled Trial Post Hoc Analysis

PURPOSE To assess if catheter-directed thrombolysis (CDT) treatment heterogeneity in the multicenter [REDACTED] RCT is associated with differences in pulmonary embolism (PE) clinical outcomes. MATERIALS AND METHODS All [REDACTED] CDT arm patients were eligible for post hoc analysis, excluding those treated with multiple CDT device types (n=8), non-tPA thrombolytics (n=10), or pharmacomechanical CDT (n=12). Patients were grouped by treatment: ultrasound-accelerated CDT (USAT) or standard CDT (SCDT). Treatment protocols were assessed, and clinical, safety, and quality-of-life outcomes were compared at discharge/7 days, 24 hours, and/or 30 days. RESULTS 159 USAT and 87 SCDT patients were included. Longer mean treatment duration (12.4 vs 20.8 hours, p<0.001), higher mean thrombolytic dose (17.2 vs 23.4mg tPA, p<0.001), and more ICU stays >24 hours (57.4% vs 80.5%, p<0.001) were identified in the SCDT group. However, in-hospital outcomes were not different, including all-cause mortality (0.0% vs 1.1%, p=0.35), intracranial hemorrhage (0.6% vs 0.0%, p=1.00), major bleeding (5.7% vs 10.3%, p=0.20), and clinical deterioration and/or bailout (5.0% vs 5.7%, p=0.77). RV/LV ratio reduction (19.9% vs 23.1%, p=0.10) and respirations per minute (20.0 vs 19.9, p=0.62) were not statistically different at the 24-hour visit. PEmb-QoL (18.5 vs 23.0, p=0.18) and EQ-5D-5L (0.84 vs 0.81, p=0.85) were also not different at the 30-day visit. CONCLUSION Treatment duration and tPA dose were significantly lower in patients treated with USAT; however, clinical outcomes did not differ significantly between USAT and SCDT. This suggests that the primary analysis of [REDACTED] may be generalizable to tPA-based CDT treatment protocols currently in use.