Impact of catheter-directed therapy for acute pulmonary embolism on subsequent CTEPH hemodynamics

Background

Pulmonary embolism (PE) is an important risk factor for chronic thromboembolic pulmonary hypertension (CTEPH). Catheter-directed therapy (CDT) is an emerging treatment modality for acute PE. It allows to achieve rapid thrombus reduction and to improve right ventricular function in the acute setting. However, whether CDT influences long-term pulmonary vascular remodeling or alters the progression to CTEPH remains uncertain.

Objective

To compare hemodynamic variables between CTEPH patients with a history of acute PE treated with CDT and those managed without CDT.

Methods

Retrospective analysis of consecutive patients with prior PE and established CTEPH under regular follow-up at a specialized PH center. Echocardiographic and hemodynamic parameters were collected and compared between those with CDT and those without. Chi-square test and t-test for independent samples were used to compare groups.

Results

38 patients with CTEPH and prior PE were evaluated (mean age 66± 15.2 years, 64% females). 84.6% had an intermedia-high PE, 29%(n=11) treated with CDT. CDT group was younger (57.1±22.3 vs 70.1±9.5 years, p= 0.088) and predominantly female (91%).

Hemodynamic assessment showed significantly higher cardiac output (6.0±1.2 vs. 4.6±1.2 L/min; p=0.002) and cardiac index (3.2±0.7 vs. 2.5±0.5 L/min/m2; p<0.001) in the CDT group. Mean pulmonary artery pressure and pulmonary vascular resistance were lower in CDT-treated patients, although not significantly. Venous oxygen saturation demonstrated a non-significant trend toward higher values

(p=0.052). Echocardiography revealed lower es#mated PASP (40.4±15.5 vs. 63.5±22.2 mmHg; p=0.012) and a higher TAPSE/PASP ratio (0.53±0.09 vs. 0.34±0.21; p=0.035) in the CDT group, while other right heart structural parameters did not differ.

Conclusion

Overall, CDT during acute PE was associated with a more favorable hemodynamic profile at CTEPH diagnosis. These findings are in alignment with recent clinical trials and registries that suggest early catheter-directed reperfusion may positively influence long-term pulmonary vascular remodeling, potentially attenuating disease severity or even lowering the likelihood of progression to CTEPH. More data and long-term follow-up are needed to prove this theory.For image description, please refer to the figure legend and surrounding text.