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Updated: Jan 9, 2026

Catheter-based Endovascular Angioplasty for Fibrosing Mediastinitis-associated Pulmonary Vein Stenosis
Published on: August 26, 2025
Upfront combination therapy with sildenafil and ambrisentan in patients with chronic thromboembolic pulmonary
William Salibe-Filho1, Tulio Martins Vieira1, José Leonidas Alves-Junior1
1. Divisão de Pneumologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil.
Objective:
Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism, being characterized by persistent obstruction of pulmonary vessels and leading to increased pulmonary vascular resistance and right ventricular failure. Although pulmonary endarterectomy is the preferred treatment, medical therapies may offer clinical benefits in specific settings. We sought to evaluate the clinical and hemodynamic response of CTEPH patients treated with sildenafil and ambrisentan upfront combination therapy.
Methods:
This was a retrospective cohort study including patients with operable and inoperable CTEPH. The patients were followed from 2019 to 2022 and were treated with sildenafil and ambrisentan as first-line therapy.
Results:
Functional and hemodynamic data were analyzed at baseline and after a minimum of six months of therapy. Following treatment, there was a notable improvement in functional class, natriuretic peptide levels, and invasive hemodynamics.
Conclusions:
The combined use of sildenafil and ambrisentan appears to be associated with clinical, functional, and hemodynamic improvement in patients with CTEPH.
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