Catheter-directed treatment in acute pulmonary embolism
Authors: Keller K , Schmidt F , Mohr K , Farmakis I , Christodoulou K , Valerio L , Barco S , Gori T , Munzel T , Lurz P , Konstantinides S , Hobohm L 
Published: October 2024

Abstract

Background
Pulmonary embolism (PE) is a potentially life-threatening emergency. PE occurs when venous thrombi embolize to the pulmonary circulation, resulting in vascular occlusion, impairing gas exchange and circulation. Initial risk stratification of acute PE is based on clinical symptoms, cardiac adaptations, comorbidities, and, in particular signs of haemodynamic instability. The primary aim of the treatment is to restore blood flow to the affected areas of the lungs, resolving/removing embolus burden and preventing further clot formation. In patients with severe PE, comprising decompensation or intended hemodynamic compromise, immediate reperfusion is recommended. Catheter-directed therapies (CDT) are an innovative treatment option for patients with severe PE to resolve embolus and restore pulmonic perfusion. These procedures are less invasive and are supposed to have a lower risk of bleeding complications compared to systemic thrombolysis or surgical embolectomy. Recent studies have shown that CDT are safe and effective treatment options for PE.

Purpose
Nevertheless, CDT have to demonstrate their non-inferiority and benefits regarding patients’ outcomes in real-world settings.

Methods
The German nationwide inpatient sample was used to identify and include all hospitalizations of patients with PE 2005-2020 in Germany. PE patients were stratified for use of CDT. Temporal trends of the usage and the impact of CDT on case-fatality and other outcomes were investigated (source: RDC of the Federal Statistical Office and the Statistical Offices of the federal states, DRG Statistics 2005-2020, own calculations).

Results
Overall, 1,373,084 hospitalisations of patients with PE (55.9% aged ≥70 years; 53.0% females) were included in this study 2005-2020. Among these, 427,238 (31.1%) were categorized as severe PE and 3330 (0.2%) were treated with CDT with an annual increase from 0.17% (2005) to 0.51% (2020). PE patients of younger age, male sex, with previous surgery, and with severe PE were more often treated with CDT. In patients with severe PE, CDT was attributed to lower MACCE (28.2% vs. 34.2%, P&lt;0.001) and in-hospital case-fatality rate (24.9% vs. 31.0%, P&lt;0.001), but higher prevalence of major bleeding (29.5% vs. 17.5%, P&lt;0.001). CDT was associated with reduced MACCE (OR 0.91 [95%CI 0.83-0.99], P=0.031), a trend towards lower case-fatality (OR 0.92 [95%CI 0.84-1.01], P=0.068), but increased major bleeding (OR 2.12 [95%CI 1.92-2.33], P&lt;0.001) in severe PE. The benefit of CDT regarding case-fatality was age-dependent, with the largest benefit in the 8th and 9th decade of life.

Conclusions
Although the annual rate of CDT increased from 2005 to 2020 in Germany, only 0.2% of the PE patients were treated with CDT. Selection criteria for CDT treatment were younger age, male sex, previous surgery, and severe PE. CDT treatment was associated with reduced MACCE and case-fatality rate in PE patients with severe PE.