Classification of Pulmonary Hypertension
The WHO Group Classification of Pulmonary Hypertension (Dana Point version) helps categorize pulmonary hypertension (PH) by type and the New York Heart Association (NYHA) Functional Classification measures symptoms severity associated with PH. Both classification systems are below. All Pulmonary Hypertension (PH) is not Pulmonary Arterial Hypertension (PAH).
Clinical Classification of Pulmonary Hypertension
(updated at 5th WSPH, Nice, France 2013)
The World Health Organization (WHO) first defined the classifications of pulmonary hypertension in 1973 and the classifications have been revised over the years. The classifications of PH were most recently updated in Nice, France in 2013.
1. Pulmonary arterial hypertension (PAH)
1.1 Idiopathic (IPAH)
1.2 Heritable (HPAH) (previously known as Familial (FPAH)
1.2.2 ALK-1*, ENG*, SMAD9*, CAV1*, KCKN3*
1.3 Drug and toxin induced
1.4 Associated with (APAH) (previously known as Secondary (SPAH)
1.4.1 Connective tissue diseases
1.4.2 HIV* infection
1.4.3 Portal hypertension
1.4.4 Congenital heart diseases
1'. Pulmonary veno-occlusive disease (PVOD) and/or pulmonary capillary hemangiomatosis (PCH)
1''. Persistent pulmonary hypertension of the newborn (PPHN)
2. Pulmonary hypertension owing 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 owing to lung diseases 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 lung diseases
4. Chronic thromboembolic pulmonary hypertension (CTEPH)
5. Pulmonary hypertension with unclear multifactorial mechanisms
5.1 Hematologic disorders: chronic hemolytic anemia, 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: tumoral obstruction, fibrosing mediastinitis, chronic renal failure, segmented PH
Main modifications to the previous Dana Point 2008 classification are shown in bold.
*ALK1 = activin receptor-like kinase type 1; BMPR2 = bone morphogenetic protein receptor type 2; HIV = human immunodeficiency virus; ENG = endoglin;SMAD9 = mothers against decapentaplegic 9; CAV1 = caveolin-1; KCNK3 = a gene encoding potassium channel super family K member-3
World Health Organisation (WHO) Functional Classification of PH
Reference is often made to functional class of PH. The World Health Organization (WHO) has developed a system based on a modified New York Heart Association (NYHA) classication system of left heart failure severity. This was created to help doctors determine how limited a patient is in their ability to do the activities of daily living. In general, patients with more severe PH tend to have a higher functional class.
Patients with pulmonary hypertension but without resulting limitation of physical activity. Ordinary physical activity does not cause undue dyspnea or fatigue, chest pain, or near syncope.
Patients with pulmonary hypertension resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity causes undue dyspnea or fatigue, chest pain, or near syncope.
Patients with pulmonary hypertension resulting in marked limitation of physical activity. They are comfortable at rest. Less-than-ordinary physical activity causes undue dyspnea or fatigue, chest pain, or near syncope.
Patients with pulmonary hypertension with inability to carry out any physical activity without symptoms. These patients manifest signs of right heart failure. Dyspnea and/or fatigue may even be present at rest. Discomfort is increased by any physical activity.