Update from the World Symposium on Pulmonary Hypertension 2018: does the new hemodynamic definition of pediatric pulmonary hypertension have an impact on treatment strategies?

Pediatric pulmonary arterial hypertension (PAH) is a progressive life-threatening disease of the pulmonary vasculature and is defined as an elevation of the mean pulmonary arterial pressure. Before the 6th World Symposium on Pulmonary Hypertension (WSPH) in 2018, pulmonary hypertension (PH) used to be defined as a mean pulmonary artery pressure (mPAP) of ≥25 mmHg. On the WSPH a revised hemodynamic definition of PH was introduced lowering the threshold for a normal mPAP from <25 to <21 mmHg. The Pediatric Task Force chose to follow this newly proposed definition of PH in order to speak a uniform language and facilitate transition to adult services. In this opinion paper we discuss the rationale behind the new PH definition and the impact on pediatric PH. We conclude, that to date, there is no evidence in children, suggesting that this decrease of threshold for PH warrants any further measures than clinical outpatient-follow-up. Hitherto, the new definition does not impact on currently applicable treatment strategies in children with PH.