Primary pulmonary hypertension

Alternative names:

idiopathic pulmonary hypertension; pulmonary hypertension

Definition:

A disorder in which the blood pressure in the pulmonary (lung) arteries is abnormally high in the absence of other diseases of the heart or lungs.

Causes, incidence, and risk factors:

The cause of primary pulmonary hypertension is unknown. Pulmonary hypertension develops as a response to increased resistance to blood flow. Diffuse narrowing of the pulmonary arterioles occurs. The right side of the heart becomes enlarged due to the increased work load of pumping blood against this resistance. Eventually, progressive heart failure develops.

People at risk are women between 20 and 40 years old, although the disease can affect any sex and age. The incidence is 8 out of 100,000 people. It is rare in children. More common is pulmonary hypertension in infants with persistent fetal circulation.