Table 1. Clinical classification of pulmonary hypertension (PH)
ClassificationSub-classification
1. Pulmonary arterial hypertension1.1 Idiopathic
1.2 Heritable
1.3 Drugs and toxins induced
1.4 Associated with (APAH)
1.4.1 Connective tissue diseases
1.4.2 HIV infection
1.4.3 Portal hypertension
1.4.4 Congenital heart disease
1.4.5 Schistosomiasis
1.4.6 Chronic haemolytic anaemia
1.5 Persistent PH of the newborn
1′. Pulmonary veno-occlusive disease and/or pulmonary capillary haemangiomatosis
2. PH due to left heart disease2.1 Systolic dysfunction
2.2 Diastolic dysfunction
2.3 Valvular disease
3. PH due to lung diseases and/or hypoxaemia3.1 Chronic obstructive pulmonary disease
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. Chronic thromboembolic PH
5. PH with unclear and/or multifactorial mechanisms5.1 Haematological disorders: myeloproliferative disorders and splenectomy
5.2 Systemic disorders: sarcoidosis, pulmonary Langerhans’ cell histiocytosis, lymphangioleiomyomatosis neurofibromatosis and vasculitis
5.3 Metabolic disorders: glycogen storage disease, Gaucher disease and thyroid disorders
5.4 Others: tumoural obstruction, fibrosing mediastinitis and chronic renal failure on dialysis
  • Reproduced from [2] with permission from the publisher.