Pulmonary vascular disease: pulmonary thromboembolism and pulmonary hypertension

The pulmonary circulation is a high-flow, low-pressure circuit that is highly adapted for efficient gas exchange. Pathological events in the pulmonary circulation either seriously impair ventilation–perfusion matching, resulting in increased dead space, or increase pulmonary vascular resistance, putting extra load on the right ventricle that ultimately leads to right heart failure. This article explores the pathophysiology, clinical presentation, diagnosis and treatment of two major diseases affecting the pulmonary circulation – pulmonary thromboembolism and pulmonary hypertension.