How is Pulmonary Arterial Hypertension classified?

Pulmonary arterial hypertension (PAH) is associated with a number of conditions. These include:

• at times, no underlying cause can be found. In this case, it is called Idiopathic Pulmonary Hypertension (iPAH), formerly known as Primary pulmonary hypertension (PPH)

• 10% of cases are found to have been inherited from a family member (Familial Pulmonary Arterial Hypertension)

• diseases that affect connective tissue and Collagen such as systemic sclerosis (scleroderma) and systemic lupus erythematosus (SLE)

• HIV (Human immunodeficiency virus) infection

• raised blood pressure in the portal vein entering the liver (Portal hypertension)

• certain types of heart disease that have been present since birth such as a congenital systemic to pulmonary shunt

• sickle cell disease

• the development of PAH is also associated with taking appetite-suppressant drugs such as fenfluramine or dexfluramine. However, this is a less common problem nowadays as these drugs are no longer available