Hypertension, Pulmonary

It is usually secondary to underlying heart diseases or lung diseases. Chronic thromboembolic pulmonary hypertension is described as a rare complication of acute pulmonary embolism, with proximal pulmonary artery occlusion by fibrotic intravascular material.

The core abnormality is increased resistance in the pulmonary vascular bed, which raises pulmonary vascular pressure and can lead to progressive right heart failure. In chronic thromboembolic pulmonary hypertension, fibrotic obstruction of proximal pulmonary arteries together with secondary microvasculopathy increases pulmonary vascular resistance. Literature also describes immune-cell infiltration, cytokine and chemokine signaling, and inflammation as contributors to pulmonary vascular remodeling and disease progression.

Underlying heart disease and lung disease increase risk because pulmonary hypertension is usually secondary to these conditions. Acute pulmonary embolism is a risk factor for chronic thromboembolic pulmonary hypertension, and specific genetic variants are associated with increased risk in pulmonary arterial hypertension.

Management is described at the modality level and depends on the cause and lesion type. For chronic thromboembolic pulmonary hypertension, treatment includes lifelong anticoagulation, surgery, angioplasty, and medical therapy. Broader pulmonary hypertension management also includes targeted medical treatment, and in selected contexts immunotherapy or anti-inflammatory approaches are being considered.