Abstract Body (Do not enter title and authors here): Background: Catheter-Directed Interventions (CDIs) for Acute Pulmonary Embolism (PE) have been present for years but their use is limited due to paucity of data especially in patients with cancer. We examine the safety and efficacy of CDIs in patients with high-risk PE and cancer.

Methods: Nationwide Readmissions Database (2016-2021) was used to analyze cancer patients presenting with high-risk PE (HR-PE) (shock, pressor or mechanical circulatory support requirement). Patients who received systematic thrombolysis were excluded. Mahalanobis Distance Matching within the Propensity Score Caliper was used to match patient who received CDIs vs those who were treated with anticoagulation alone. Inverse Probability weighting (IPW) was utilized, and Pearson’s chi-squared test was applied to the PSM-2 matched cohorts to compare outcomes.

Results: Among 265,196 hospitalization of cancer patients with HR-PE, X were treated with systemic thrombolysis and 795 (0.3%) of the patients underwent CDI.
After propensity matching (N: 421 in each group), patients receiving CDI had a significantly lower mortality (33% vs. 41.8%, aOR:0.76 (95% CI, p: 0.008); However, bleeding complications including major bleeding (10.7% vs 6.2%, aOR:1.97 (95% CI, p: 0.018) was higher in patients receiving CDIs. No difference was observed in the risk of intracerebral hemorrhage (p>0.05). Readmission rates were similar at 30-day and 90-day intervals (p>0.05). From 2016-2021, mortality associated with HR-PE in cancer has not changed significantly (p>0.05); however, mortality in patients undergoing CDIs has decreased from (43.8% to 22.6%, p-trend: 0.0004). There has been increasing use of mechanical thrombectomy (MT) over thrombolysis in recent years.

Conclusion: CDIs for HR-PE in cancer patients are associated with significant reduction in mortality and associated with higher bleeding. Mortality has decreased across the years for patients undergoing CDIs with higher utilization of MT.