1

PAH

1.1

Idiopathic PAH

1.2

Heritable

1.2.1

BMPR2

1.2.2

ALK1, endoglin (with or without hereditary haemorrhagic telangectasia)

1.2.3

Unknown

1.3

Drug and toxin induced

1.4

Associated with:

1.4.1

Collagen tissue diseases

1.4.2

HIV infection

1.4.3

Portal hypertension

1.4.4

Congenital heart diseases

1.4.5

Schistosomiasis

1.4.6

Chronic haemolytic aneamia

1.5

Associated with significant venous or capillary involvement

1.5.1

Pulmonary veno-occlusive disease

1.5.2

Pulmonary capillary haemangiomatosis

1.6

Persistent PH of the newborn

2

PH with left heart disease

2.1

Left-sided atrial or ventricular heart disease

2.2

Left-sided valvular heart disease

3

PH associated with lung diseases and/or hypoxaemia

3.1

COPD

3.2

Interstitial lung disease

3.3

Other pulmonary diseases with mixed restrictive and obstructive pattern

3.4

Sleep-disordered breathing

3.5

Alveolar hypoventilation disorders

3.6

Chronic exposure to high altitude

3.7

Developmental abnormalities

4

CTEPH

5

PH with unclear multifactorial mechanisms

5.1

Haematologic disorders: myeloproliferative disorders, splenectomy

5.2

Systemic disorders: sarcoidosis, pulmonary Langerhans cell histiocytosis, lymphangioleiomyomatosis, neurofibromatosis, vasculitis

5.3

Metabolic disorders: glycogen storage disease, Gaucher’s disease, thyroid disorders

5.4

Others: tumoral obstruction, fibrosing mediastinitis, chronic renal failure on dialysis