Table 1 Updated clinical classification of pulmonary hypertension#
1. PAH
 1.1. Idiopathic PAH
 1.2. Heritable PAH
  1.2.1. BMPR2
  1.2.2. ALK1, ENG, SMAD9, CAV1, KCNK3
  1.2.3. Unknown
 1.3. Drug and toxin induced
 1.4. Associated with:
  1.4.1. Connective tissue disease
  1.4.2. HIV infection
  1.4.3. Portal hypertension
  1.4.4. Congenital heart diseases
  1.4.5. Schistosomiasis
 1′ Pulmonary veno-occlusive disease and/or pulmonary capillary haemangiomatosis
 1″ Persistent PH of the newborn
2. PH due to left heart disease
 2.1. Left ventricular systolic dysfunction
 2.2. Left ventricular diastolic dysfunction
 2.3. Valvular disease
 2.4 Congenital/acquired left heart inflow/outflow tract obstruction and congenital cardiomyopathies
3. PH due to lung diseases and/or hypoxia
 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 lung diseases
5. PH with unclear multifactorial mechanisms
 5.1. Haematological disorders: chronic haemolytic anaemia, myeloproliferative disorders, splenectomy
 5.2. Systemic disorders: sarcoidosis, pulmonary histiocytosis, lymphangioleiomyomatosis
 5.3. Metabolic disorders: glycogen storage disease, Gaucher disease, thyroid disorders
 5.4. Others: tumoural obstruction, fibrosing mediastinitis, chronic renal failure, segmental PH
  • #: from the Fifth World Symposium on Pulmonary Hypertension (Nice, France, 2013). Reproduced from [7] with permission from the publisher.