Pulmonary hypertension: clinical classification
Pulmonary hypertension is a clinical and haemodynamic condition associated with several baseline clinical conditions or existing as a pure pulmonary vascular disease. The current classification groups aetiologies of pulmonary hypertension that share similarities in terms of clinical presentation, pathological findings, and haemodynamic profiles, in an attempt to guide management strategies in these distinct conditions. As a consequence, pulmonary hypertension is classified into five different groups: pulmonary arterial hypertension, pulmonary hypertension due to left heart disease, pulmonary hypertension due to lung disease and/or hypoxia, chronic thromboembolic pulmonary hypertension, and pulmonary hypertension with unclear multifactorial mechanisms. This chapter reviews the rational supporting the current classification system alluding also to the existing evidence for specific therapies in each one of the groups.