Table 2

Clinical classification of pulmonary hypertension4

Group 1: PAHIdiopathic PAH
Heritable PAH
Drug and toxin-induced PAH
PAH associated with:
  • Connective tissue disease

  • HIV infection

  • Portal hypertension

  • Congenital Heart disease

  • Schistosomiasis

PAH long-term responders to calcium channel blockers
PAH with over features of venous/capillary (PVOD/PCH) involvement
Persistent PH of the newborn syndrome
Group 2: PH due to left heart diseasePH due to heart failure with preserved left ventricular ejection fraction
PH due to heart failure with reduced left ventricular ejection fraction
Valvular heart disease
Congenital/acquired cardiovascular conditions leading to postcapillary PH
Group 3: PH due to lung diseases and/or hypoxiaObstructive lung disease
Restrictive lung disease
Other lung disease with mixed restrictive/obstructive pattern
Hypoxia without lung disease
Developmental lung disorders
Group 4: PH due to pulmonary artery obstructionChronic thromboembolic PH
Other pulmonary artery obstructions: sarcoma or angiosarcoma, other malignant tumors (renal carcinoma, uterine carcinoma, germ cell tumors), non-malignant tumors (uterine leiomyoma), arteritis without connective tissue disease, congenital pulmonary artery stenosis, parasites (hydatidosis)
Group 5: PH with unclear and/or multifactorial mechanismsHematologic disorders: chronic hemolytic anemia, myeloproliferative disorders
Systemic and metabolic disorders: pulmonary Langerhans cell histiocytosis, Gaucher disease, glycogen storage disease, neurofibromatosis, sarcoidosis
Others: chronic renal failure with or without hemodialysis, fibrosing mediastinitis
Complex congenital heart disease
  • PAH, pulmonary arterial hypertension; PCH, pulmonary capillary hemangiomatosis; PH, pulmonary hypertension; PVOD, pulmonary veno-occlusive disease.