COPD and pulmonary hypertension

Pulmonary hypertension (PHT) is a common complication in chronic respiratory diseases and specifically in chronic obstructive pulmonary disease (COPD), although its prevalence has not been well determined. PHT affects functional capacity and survival in these patients. This complication is usually moderate or mild and develops when airflow obstruction is severe. However, some patients have "disproportionate" PHT, despite minimal functional involvement and optimal treatment. Although alveolar hypoxia has classically been considered to be the main cause, in the last few years other pathogenic mechanisms have been identified, especially those producing vascular remodelling, which are reviewed in the present article. Lastly, the diagnostic approach and therapeutic management of PHT in patients with COPD are analyzed.