B54-44 Comparing Ninety-Day Survival Across Intervention Strategies for Intermediate and High-Risk Pulmonary Embolism Using Propensity Score Matching

Rationale There is limited comparative data on short-term survival outcomes among patients with intermediate and high-risk pulmonary embolism (PE) treated with contemporary therapeutic strategies. We sought to compare 90-day survival between patients treated with Heparin alone, Percutaneous Mechanical Thrombectomy (PMT), and Catheter-Directed Thrombolysis (EKOS), using propensity score-matched analyses to account for baseline differences. Methods This retrospective cohort study was conducted at a tertiary academic center (University of Cincinnati) and included 590 adult patients categorized as intermediate-low, intermediate-high, or high-risk PE (PE Risk Group). Exclusion criteria included cancer-related hospice deaths, withdrawal of care prior to treatment, contraindications to anticoagulation, surgical embolectomy, and suspected or confirmed chronic thromboembolic pulmonary hypertension (CTEPH). Two separate 1:1 optimal propensity score matching models were performed: Model 1, matched by simplified Pulmonary Embolism Severity Index (sPESI) and sex; Model 2, matched by sex, age, and PE risk group. Kaplan-Meier curves were compared using the log-rank test, and Cox proportional hazards models estimated hazard ratios (HRs) for 90-day survival. Results In the unmatched cohort, no significant survival differences were observed between groups (global log-rank p = 0.12; KM p = 0.78). Compared with heparin (N = 221), hazard ratios for 90-day mortality were 0.51 [95% CI 0.24-1.1; p = 0.074] for EKOS and 0.66 [95% CI 0.28-1.5; p = 0.33] for PMT. After propensity score matching, 142 patients were included in Model 1 and 102 in Model 2. • Model 1 (sPESI + sex): PMT vs. Heparin, HR = 0.76 (p = 0.48); Heparin vs EKOS, HR = 0.56 (p = 0.06); EKOS vs PMT, HR = 1.3 (p = 0.57). • Model 2 (sex + age + risk group): PMT vs. Heparin, HR = 0.44 [95% CI 0.22-0.87; p = 0.015]; Heparin vs EKOS, HR = 0.55 [95% CI 0.3-1.0; p = 0.048]; EKOS vs PMT, HR = 1.2 [95% CI 0.55-2.8; p = 0.61]. PMT was associated with improved 90-day survival compared with Heparin though no significant difference compared to EKOS in Model 2. Conclusion In this single-center cohort of intermediate and high-risk PE, unadjusted analyses showed no survival difference among intervention strategies. However, after adjusting for age, sex, and risk group, PMT was associated with improved 90-day survival compared with Heparin, and no significant difference from EKOS. These findings highlight the importance of risk-adjusted analysis in evaluating outcomes for advanced PE therapies. Further directions include multi-center analyses to increase the sample of matched patients, and comparison of composite endpoints including length-of-stay (LOS) and morbidity.