Catheter-directed therapies impact on intermediate-high- and high-risk pulmonary embolism patients
Authors: Grazina A , Lacerda Teixeira B , Almeida Morais L , Fiarresga A , Ramos R , Sousa L , Reis J , Galrinho A , Santana A , Teles Antunes H , Cacela D , Cruz Ferreira R 
Published: November 2023

Abstract

Introduction
Intermediate-high- and high-risk pulmonary embolism (PE) patients treated with anticoagulation alone are associated with a considerable risk of circulatory collapse, death, or long-term pulmonary hypertension. Pulmonary Embolism Response Teams (PERT) have been created to deliver PE patients a better care. Catheter Directed Therapies (CDT), with mechanical thrombolysis and/or local fibrinolysis allow faster reperfusion and hemodynamic improvement without the systemic hemorrhagic effects of systemic fibrinolysis. The clinical evidence of its benefits is lacking.

Objectives
This analysis aims to describe the hemodynamics, morphological and perfusion improvement in intermediate-high- and high-risk acute PE patients submitted to CDT.

Methods
Prospective registry of consecutive intermediate-high- and high-risk PE patients submitted to CDT (mechanical thrombolysis with PenumbraÔ aspiration system and/or intrapulmonary local fibrinolysis with alteplase) in a single tertiary center. A multiparametric follow-up protocol was designed to evaluate echocardiographic, CT-scan, pulmonary angiogram, and right heart catheterization data at admission and at 3 months after CDT. The paired samples t-Test was used for the analysis of the variables.

Results
26 PE patients (42.3% male, mean age 59 years old) were submitted to CDT (19% combined Penumbra and local fibrinolysis, 12% isolated Penumbra and 69% isolated local fibrinolysis). Baseline characteristics, laboratorial, imaging and procedure data are summarized in the figure 1. No major bleeding was seen during or after the procedure. 1 pulmonary artery dissection and 1 Penumbra burr partial avulsion occurred, both with conservative treatment with good result. 3 patients died during the follow-up (1 for oncologic disease, 1 for septic shock and 1 after discharge with undetermined cause). Of the remaining, 18 patients completed the 3-month follow-up protocol. At 3 months, a significant improvement was seen in the patients’ hemodynamics with 3.3mmHg mean drop of RA pressure (p 0.007), 16.1mmHg mean drop of systolic PA pressure (p &lt;0.001), 8.0mmHg mean drop of mean PA pressure (p&lt;0.001), 1.4L/min and 0.7L/min/m2 mean increases in cardiac output and index (p 0.003, p 0.001), and a tendency to a 0.8 Wood units decrease in the pulmonary vascular resistance (p 0.093). It was also seen an improvement in the perfusion defects with a mean drop of 7.9 points in the modified Miller index (p &lt;0.001) and an improvement in the RV function with a mean decrease of 0.5 in the RV/LV ratio by CT-scan (p &lt;0.001), a mean increase of 5.6mm in TAPSE (p &lt;0.001) and a decrease of median NT-proBNP levels in 2866pg/ml (p &lt;0.001).

Conclusions
In patients with intermediate-high- and high-risk PE, the use of CDT with mechanical thrombolysis and/or local fibrinolysis is safe and associated with improvement in hemodynamics, RV function and perfusion defects.Table 1.baseline characteristicsTable 2.results