Chronic Obstructive Pulmonary Disease and Pulmonary Hypertension

Pulmonary hypertension (PH) is a common complication of chronic obstructive pulmonary disease (COPD). The increase in pulmonary artery pressure (PAP) is often mild to moderate. However, 5-10% of patients with advanced COPD may suffer from severe pulmonary hypertension. A small proportion of COPD patients may present with "out-of-proportion'' PH, defined by a mean PAP > 35-40 mmHg and a relatively preserved lung function that can not explain prominent dyspnea and fatigue. In patients with of COPD, PH is associated with bad prognosis. The cause of pulmonary hypertension in COPD is generally assumed to be hypoxic pulmonary vasoconstriction. Recently, interest in the cellular and molecular aspects of the pathophysiology of PH in COPD has increased. The most striking finding is the role of vascular endothelial cells and endogenous mediators released by these cells. Pulmonary vascular remodelling in COPD is the main cause of increase in pulmonary artery pressure. At the present, there is no specific and effective treatment for this condition in COPD. The timing of initiation of long-term oxygen therapy is important for the effective management of PH in COPD. Research on therapeutic agents for the effective treatment of PH is still needed in the management aspect of patients with COPD. This review focuses on the recent advances in our understanding of the pathophysiology and treatment of PH in COPD.