Pulmonary arterial hypertension

**Definition:** Pulmonary arterial hypertension is a clinical condition characterised by the presence of pre-capillary pulmonary hypertension in the absence of other causes of pre-capillary pulmonary hypertension, such as due to lung diseases, chronic thromboembolic pulmonary hypertension, or other rare diseases. It includes different forms that share a similar clinical picture and virtually identical pathological changes of the lung microcirculation.

**Inclusions:** - primary pulmonary hypertension - Idiopathic pulmonary arterial hypertension