Pulmonary hypertension

Abstract

Symptoms of unexplained exertional breathlessness or symptoms out of proportion to coexistent heart or lung disease should alert the clinician to the possibility of pulmonary hypertension, and the condition should be actively sought in patients with known associated conditions, such as scleroderma, hypoxic lung disease, liver disease, or congenital heart disease. Heterozygous germ-line mutations in the gene encoding the bone morphogenetic protein type II receptor (BMPR2) are found in over 70% of families with pulmonary arterial hypertension. Pulmonary hypertension is defined as a mean pulmonary arterial pressure greater than 25 mm Hg at rest, and may be due to increased pulmonary vascular resistance (e.g. pulmonary arterial hypertension), increased transpulmonary blood flow (e.g. congenital heart disease), or increased pulmonary venous pressures (e.g. mitral stenosis). Exercise tolerance and survival in pulmonary hypertension is ultimately related to indices of right heart function, such as cardiac output.