Pulmonary hypertension (PH) is a complex and often misunderstood disease. PH means high blood pressure in the lungs. PH is different from regular hypertension. In regular hypertension (also known as high blood pressure), the arteries throughout a person’s body are constricted. In pulmonary hypertension, the blood vessels in the lungs become narrowed and the heart has to work harder to pump blood through them.
In many cases, no cause can be identified, and in these cases the disease is referred to as idiopathic pulmonary arterial hypertension (IPAH). Sometimes PH can develop due to another medical condition, including connective tissue disease, congenital heart disease, liver disease, HIV, and others. This type of PH is known as associated pulmonary arterial hypertension (APAH). Some families have a form of PH that can be inherited. This is known as heritable pulmonary arterial hypertension (HPAH).