Mild-to-moderate pulmonary hypertension (PH) is a common complication of advanced chronic obstructive pulmonary disease (COPD). The presence of PH is associated with an increased risk of acute exacerbation and decreased survival.

Patients with COPD may present with severe elevation of pulmonary artery pressure (mean pulmonary artery pressure >35–40 mmHg). This is observed in end-stage disease, left heart disease or another COPD-associated respiratory disorder. A small proportion of patients may develop severe PH without any concomitant heart or lung disease other than COPD. These patients have unusual cardiopulmonary abnormalities with moderate airflow limitation, severe hypoxaemia, hypocapnia, a very low diffusing capacity of the lung for carbon monoxide and pulmonary haemodynamic characteristics similar to those of idiopathic pulmonary arterial hypertension (IPAH). Survival in this latter population of COPD is severely compromised. Right heart catheterisation (RHC) is mandatory when severe PH is suspected.

Management of PH in COPD relies on ruling out comorbidities, optimising therapy for COPD and long-term oxygen therapy. Specific treatment developed for IPAH should not be prescribed in COPD patients outside controlled trials or experienced PAH centre.