Pulmonary arterial hypertension (PAH) is a serious disease of the pulmonary arteries connecting the right side of the heart to the lungs. As PAH develops, blood flow through the pulmonary arteries is restricted and the right side of the heart is put under increasing strain to pump blood through to the lungs. This leads to the main symptoms of PAH – breathlessness, chest tightness, limited exercise capacity and fatigue.

Untreated, PAH is a disease with a very poor prognosis.

Treatment is aimed at improving symptoms, exercise tolerance, long-term outcomes and quality of life. Until the mid-1980s, there were no treatment options for patients, and PAH was associated with poor prognosis. Today, treatment options have improved the outlook for patients with this condition.