Table 1.
Comprehensive clinical classification of pulmonary hypertension (updated from Simonneau et al. [3]).
| 1. Pulmonary arterial hypertension (PAH) | 1.1. Idiopathic | |
| 1.2. Heritable | 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 the following: | 1.4.1. Connective tissue diseases | |
| 1.4.2. Human immunodeficiency virus (HIV) infection | ||
| 1.4.3. Portal hypertension | ||
| 1.4.4. Congenital heart diseases | ||
| 1.4.5. Schistosomiasis | ||
| 1′. Pulmonary veno-occlusive disease (PVOD) and/or pulmonary capillary hemangiomatosis (PCH) | 1′.1. Idiopathic | |
| 1′.2. Heritable | 1′.2.1. EIF2AK4 mutation | |
| 1′.2.2. Other mutations | ||
| 1′.3. Drug, toxin, and radiation induced | ||
| 1′.4. Connective tissue diseases | ||
| 1′.5. Human immunodeficiency virus (HIV) infection | ||
| 1″. Persistent pulmonary hypertension of the newborn (PPHN) | ||
| 2. Pulmonary hypertension 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. Pulmonary hypertension due to lung disease and/or hypoxia | 3.1. 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 pulmonary hypertension (CTEPH) | ||
| 5. Pulmonary hypertension with unclear multifactorial mechanisms | 5.1. Hematologic disorders: chronic haemolytic anaemia, myeloproliferative disorders, splenectomy | |
| 5.2. Systemic disorders: sarcoidosis, pulmonary histiocytosis, lymphangioleiomyomatosis (LAM) | ||
| 5.3. Metabolic disorders: glycogen storage disease, Gaucher disease, thyroid disorders | ||
| 5.4. Others: tumoral obstruction, fibrosing mediastinitis, chronic renal failure on dialysis, segmental PH | ||
BMPR2 = bone morphogenetic protein receptor type 2; EIF2AK4 = eukaryotic translation initiation factor 2 alpha kinase 4.