One-year Outcomes of Mechanical Thrombectomy and Catheter-Directed Thrombolysis in Acute Pulmonary Embolism

BACKGROUND: While anticoagulation remains the standard of care for acute pulmonary embolism, mechanical thrombectomy (MT) and catheter-directed thrombolysis (CDT) have emerged as effective interventional options for rapid clot removal. However, their comparative outcomes remain incompletely defined. This study aimed to compare the outcomes of MT and CDT for acute PE at a tertiary referral center in the United States. METHODS: We conducted a retrospective cohort study of all patients who underwent MT or CDT for acute PE across a single hospital system between January 2021 and April 2025. Patients were stratified into MT and CDT groups based on the treatment received. Baseline characteristics, procedural data, and clinical outcomes were analyzed. The primary outcome was 30-day mortality. Secondary outcomes included length of hospital stay, major adverse events, reintervention, and PE recurrence. Patients were followed for up to one year or until death. RESULTS: A total of 724 patients were included: 569 (79%) underwent MT and 155 (21%) received CDT. The mean age was 63 ± 16 years, and 49% were female. Most patients (76%) were classified as intermediate-high risk, with a mean right ventricle to left ventricle (RV/LV) ratio of 1.5 ± 0.5. Bilateral or saddle embolism was present in 93% of cases. Patients in the MT group were more likely to have a simplified PE severity index (sPESI) > 0 (73% vs. 60%, p < 0.001). Age, rates of cancer, chronic cardiopulmonary disease, and concurrent deep vein thrombosis were similar between groups. Median procedure duration was longer for MT (66 minutes, IQR 46-89) than CDT (58 minutes, IQR 40-77; p = 0.003). Median postoperative length of stay was 3 days in both groups. MT was associated with a higher incidence of intraoperative adverse cardiac events (2.5% vs. 0%, p = 0.048), while CDT was associated with higher ICU admission rates (83% vs. 36%, p < 0.001). However, thirty-day mortality was similar between groups (CDT: 2.6% vs. MT: 4.6%; p = 0.27). Additionally, the one-year incidences of CTEPH (MT: 4.5% vs. CDT: 3.4%, p=0.69), PE recurrence (MT: 4.4% vs CDT: 2.5%, p=0.31) and all-cause mortality (MT:7.8% vs. CDT: 5.8%, p=0.41) were not statistically significant between MT and CDT respectfully. CONCLUSION: In this retrospective cohort, MT and CDT for acute PE showed statistically comparable mortality, CTEPH, and PE recurrence rates at one-year. MT was associated with higher intraoperative cardiac complications, whereas CDT required more frequent ICU admission.