Outcomes of Mechanical Thrombectomy Compared With Systemic Thrombolysis in Pulmonary Embolism: A Comprehensive Evaluation From the National Inpatient Sample Database.

Background: Systemic thrombolysis (ST) may not be ideal for many patients with acute pulmonary embolism (PE) due to bleeding risk. In this analysis, we evaluated the safety and effectiveness of mechanical thrombectomy (MT) as an alternative to ST for acute PE.

Methods: Patients aged ≥18 years who underwent MT and/or ST for PE were identified from the National Inpatient Sample database from 2016 to 2017. Patients who underwent catheter-directed thrombolysis were excluded. We compared in-hospital outcomes of both groups in this retrospective study.

Results: Of 16 890 patients who received an intervention for acute PE, 1380 (8.2%) received MT and 15 510 (91.8%) received ST. There was no difference in age between both groups. In-hospital mortality was significantly lower in patients who received MT than that in those who received ST (11.9% vs 20.6%, odds ratio [OR]: 0.52, 95% confidence interval [CI]: 0.29-0.93, p=0.028). There was no statistically significant difference in terms of periprocedural bleeding, intracranial hemorrhage, and acute kidney injury between the 2 groups (p≥0.608 for all). Patients who received MT had a higher rate of respiratory complications (19.0% vs 11.6%, OR: 1.79, 95% CI: 1.06-3.03, p=0.030) and discharge to an outside facility (34.1% vs 19.2%, OR: 2.18, 95% CI: 1.41-3.37, p<0.001) than those who received ST.

Conclusion: Mortality was significantly lower with MT than that with ST, but larger randomized studies are needed to validate this. The use of MT should be individualized on the basis of the patients' clinical presentation, risk profile, and local resources.

Clinical impact: In this study, we utilized the National Inpatient Sample database to study the in-hospital outcomes of pulmonary embolism patients who underwent mechanical thrombectomy compared to those who underwent systemic thrombolysis. We found that the patients who were diagnosed with pulmonary embolism and underwent mechanical thrombectomy had significantly lower mortality compared to those who were treated using systemic thrombolysis. This study was the first of its kind, utilizing the national inpatient sample database for evaluation of mechanical thrombectomy in comparison with the standard of care. These result would direct further randomized controlled trials for better evaluation of the utilization of mechanical thrombectomy in the correct clinical context. Furthermore, our study demonstrated comparable peri-operative complications between the mechanical thrombectomy group and the systemic thrombolysis group. These results would direct clinicians to consider mechanical thrombectomy if clinically indicated given the promising results.