Diagnosis and classification of pulmonary hypertension

Pulmonary hypertension (PH) has been defined as on increase in mean pulmonary arterial pressure (mPAP) >= 25 mmHg at rest as assessed by right heart catheterisation (RHC). Precapillary pulmonary hypertension is defined by an increase in mPAP >= 25 mmHg and a pulmonary capillary wedge pressure (PCWP) <= 15 mmHg associated with a normal or reduced cardiac output. No definition for PH on exercise as assessed by RHC con be provided at the present time. In group 1 pulmonary arterial hypertension (PAH), the term "familial PAH" has been replaced by "heritable PAH". Heritable forms of PAH include clinically sporadic idiopathic PAH with germline mutations and clinical familial cases with or without identified germline mutations. Schistosomiasis and chronic haemolytic anaemia have been included among the group of associated PAH. Pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis hove been individualized and designated as clinical group 1'. Group 2 "Pulmonary hypertension due to left heart diseases" has been divided into 3 sub-groups: systolic dysfunction, diastolic dysfunction and valvular disease. Group 4 includes only chronic thromboembolic pulmonary hypertension without any distinction of proximal or distal forms.