World Health Organization diagnostic classification
| Pulmonary arterial hypertension |
| Primary pulmonary hypertension |
| Sporadic |
| Familial |
| Related to: |
| Collagen vascular disease |
| Congenital systemic to pulmonary shunts |
| Portal hypertension |
| HIV infection |
| Drugs/toxins |
| Anorexigens |
| Other |
| Persistent pulmonary hypertension of the newborn |
| Other |
| Pulmonary venous hypertension |
| Left-sided atrial or ventricular heart disease |
| Left-sided valvular heart disease |
| Extrinsic compression of central pulmonary veins |
| Fibrosing mediastinitis |
| Adenopathy/tumours |
| Pulmonary veno-occlusive disease |
| Other |
| Pulmonary hypertension associated with disorders of the respiratory system and/or hypoxaemia |
| Chronic obstructive pulmonary disease |
| Interstitial lung disease |
| Sleep-disordered breathing |
| Alveolar hypoventilation disorders |
| Chronic exposure to high altitude |
| Neonatal lung disease |
| Alveolar-capillary dysplasia |
| Other |
| Pulmonary hypertension due to chronic thrombotic and/or embolic disease |
| Thromboembolic obstruction of proximal pulmonary arteries |
| Obstruction of distal pulmonary arteries |
| Pulmonary embolism (thrombus, tumour, ova and/or parasites, foreign material) |
| In situ thrombosis |
| Sickle cell disease |
| Pulmonary hypertension due to disorders directly affecting the pulmonary vasculature |
| Inflammatory |
| Schistosomiasis |
| Sarcoidosis |
| Other |
| Pulmonary capillary haemangiomatosis |
Although this clinical classification is primarily concerned with causes and thus prevention and treatment, the classification is in keeping with the pathological characterisation of pulmonary hypertensive states
Pulmonary hypertension (PH) that results from identifiable causes (secondary PH) is far more common than pulmonary hypertension with no apparent cause (primary PH)
HIV: human immunodeficiency virus