Systemic Fibrinolysis in Symptomatic Intermediate-Risk Pulmonary Embolism: A Real-World Cohort Study

Background: The role of systemic fibrinolysis in patients with intermediate-risk pulmonary embolism (PE) remains controversial because of the uncertain balance between potential benefits and bleeding risk. This study evaluated the association between systemic fibrinolysis and clinical outcomes in a real-world cohort of patients with symptomatic intermediate-risk PE. Methods: This prospective observational study included consecutive patients with symptomatic intermediate-risk PE from 2009 to 2019 at a tertiary hospital. Patients receiving systemic fibrinolysis were compared with those treated with anticoagulation alone. The primary outcome was 30-day all-cause mortality. Secondary outcomes included major bleeding, and recurrent venous thromboembolism. Multivariable Cox proportional hazards regression models were used to adjust for potential confounders. Results: A total of 560 patients with symptomatic intermediate-risk PE were included, of whom 54 (9.6%) received systemic fibrinolysis. Patients receiving fibrinolysis were younger than those treated with anticoagulation alone (median age 58 vs. 73 years; p < 0.001). Thirty-day mortality occurred in 1.8% and 3.3% of patients, respectively (p = 1). After adjustment, fibrinolysis was not associated with reduced 30-day mortality (aHR 1.5; 95% CI 0.1-17.9), nor with a significant increase in 30-day major bleeding (aHR 2.6; 95% CI 0.8-8.3). Intracranial hemorrhage and VTE recurrences were rare. Conclusions: In this real-world cohort, systemic fibrinolysis was not associated with improved survival compared with anticoagulation alone, consistent with current guideline recommendations against routine fibrinolysis in intermediate-risk PE.