Review
Copyright ©The Author(s) 2015.
World J Respirol. Jul 28, 2015; 5(2): 69-77
Published online Jul 28, 2015. doi: 10.5320/wjr.v5.i2.69
Table 2 World Health Organization's classification of pulmonary hypertension[10]
Group I - PAH
Idiopathic PAH
Heritable PAH (BMPR2, ALK1, ENG, SMAD9, CAV1, KCNK3, Unknown)
Drug and toxin induced
Associated with (1) Connective tissue disease; (2) HIV infection; (3) Portal hypertension; (4) Congenital heart disease; and (5) Schistosomiasis
Pulmonary veno-occlusive disease and/or pulmonary capillary hemangiomatosis
Persistent pulmonary hypertension of the newborn
Group II - Pulmonary hypertension due to left heart disease
Left ventricular systolic dysfunction
Left ventricular diastolic dysfunction
Valvular disease
Congenital/acquired left heart inflow/outflow tract obstruction and congenital cardiomyopathies
Group III - Pulmonary hypertension due to lung diseases and/or hypoxia
Chronic obstructive pulmonary disease
Interstitial lung disease
Other pulmonary diseases with mixed restrictive and obstructive pattern
Sleep-disordered breathing
Alveolar hypoventilation disorders
Chronic exposure to high altitudes
Developmental lung disease
Group IV - Chronic thromboembolic pulmonary hypertension
Group V - Pulmonary hypertension with unclear multifactorial mechanisms
Hematologic disorders: chronic hemolytic anemia, myeloproliferative disorders, splenectomy
Systemic disorders: sarcoidosis, pulmonary histiocytosis, lymphangioleimyomatosis
Metabolic disorders: glycogen storage disease, Gaucher’s disease, hypothyroidism
Others: tumoral obstruction, fibrosing mediastinitis, chronic renal failure, segmental pulmonary hypertension
Adapted from Galiè et al[62]. BMPR: Bone morphogenic protein receptor type II; CAV1: Caveolin-1; ENG: Endoglin; HIV: Human immunodeficiency virus; PAH: Pulmonary arterial hypertension.