Comparison of short-term changes in right ventricular function after catheter-directed thrombolysis-based therapy vs. anticoagulation alone in acute intermediate-risk pulmonary embolism

Background: Intermediate-risk pulmonary embolism (PE), defined by right ventricular (RV) dysfunction without hemodynamic instability, carries a significant risk of adverse outcomes. While anticoagulation is standard therapy, the optimal treatment strategy remains controversial. Catheter-directed thrombolysis (CDT) has emerged as a potential alternative to systemic thrombolysis, but its short-term efficacy and safety remain incompletely defined. This study aimed to compare the short-term improvement in RV function and the safety of CDT plus anticoagulation with anticoagulation alone in patients with acute intermediate-risk PE. Methods: Between March 2020 and February 2023, a total of 89 patients diagnosed with acute intermediate-risk PE were retrospectively identified, including 33 patients who received CDT plus anticoagulation (CDT group) and 56 patients who received anticoagulation alone. The primary outcome was the difference in the RV/left ventricular (LV) ratio at 1 week vs. baseline. Safety outcomes included major bleeding and clinically relevant non-major bleeding (CRNMB). Results: The rate of improvement in the RV/LV ratio was significantly greater in the CDT group than in the anticoagulation group (34.0% vs. 19.4%, P0.99) or the 3-month follow-up period (6.1% vs. 3.6%, P=0.99). Conclusions: Compared to anticoagulation alone, CDT seemed to obtain a rapid short-term improvement in RV function with no statistically significant increase in bleeding observed in this cohort, although larger studies are required to verify safety.