Mortality across treatment strategies in intermediate-to-high risk pulmonary embolism in the modern era: A meta-analysis of observational studies and RCTs

Abstract

Introduction: Pulmonary embolism (PE) represents one of the leading causes of death worldwide and mainly treated with medical management, although the utility of more invasive approaches has emerged more recently. This meta-analysis aims to evaluate the 30-day mortality of intermediate-to-high risk PE across different treatment strategies.

Methods: A systematic literature review and meta-analysis was conducted using PubMed and Cochrane databases. All studies reporting 30-day mortality rates in intermediate-to-high-risk PE were included. Meta-regression analysis and sensitivity analysis were performed on the primary endpoint, 30-day mortality, and secondary endpoints (RV/LV ratio, mPAP, and long-term mortality, any bleeding events).

Results: Of the 2390 studies published between 2000 and 2022, 76 studies (74 observational and 2 RCTs for a total of 1,194,285 patients in the medical cohort and 3007 in the interventional cohort) were included. The median age was 71.4 (IQR 62.8-77.3) years, 53.6% were women. 30-day mortality in the patients treated with medical management was 9.1% (6.6-12.6). In the interventional cohort, 30-day mortality was 2.1% (1.5-3.1) while the pre- vs post-procedure change in mean difference was -6.1 mmHg (-11.2 to -1.1) for mPAP and - 0.41 (-0.51 to - 0.31) for RV/LV ratio. The overall bleeding rate in the interventional cohort was 4.9% (CI 2.6-8.9), without differences between the two strategies (RR 1.26 CI 0.89-1.78).

Conclusion: Intermediate-high-risk mortality in pulmonary embolisms treated with medical management remains high in the modern era. Despite the absence of comparative studies, an interventional approach may have a lower 30-day mortality rate and a good safety profile.

Keywords: Pulmonary embolism; Thrombolysis; meta-analysis; thrombus aspiration.