Abstract
Pulmonary hypertension (PH) is a serious potential complication of some congenital heart diseases (CHDs). PH encompasses a range of diseases which may be idiopathic or inherited, or secondary to cardiac, respiratory, systemic or thromboembolic conditions, amongst others. Our increasing understanding of the normal ranges of pulmonary haemodynamics, as well as evidence supporting the benefits of early treatment, has resulted in a number of recent revisions to the haemodynamic definition of PH. In this Review Article, we report on the recent updates to haemodynamic definitions and classification of PH, as reflected in the 2022 Pulmonary Hypertension Guidelines and particularly focus on the CHD related sub-type of PH, where the aetiology is often multi-factorial.