Chronic Thromboembolic Pulmonary Hypertension: A Worldwide View of How Far We Have Come

Excerpt

Chronic thromboembolic pulmonary hypertension (CTEPH) is classified as group 4 based on the World Health Organization (WHO) classification [1]. The diagnosis of CTEPH is predicated upon the presence of pulmonary hypertension (PH), defined via right heart catheterization as a mean pulmonary artery pressure ≥25 mm Hg at rest, in association with persistent pulmonary perfusion defects, despite therapeutic anticoagulation [2]. In CTEPH patients, after an episode or more of pulmonary embolism (PE), there is incomplete resolution of emboli that obstruct or narrow elastic pulmonary arteries. In addition, a progressive distal small vessel vasculopathy develops overtime [3]. The combination of large vessel obstruction and microvascular disease accounts for the elevated pulmonary pressures, and dictate the treatment approach: surgical removal of fibrotic thrombi, the preferred approach versus medical therapy [4]. …