Shaping the future of paediatric pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe progressive pulmonary vascular disease with a detrimental prognosis. The studies described in this thesis give specific paediatric data that is necessary to improve outcome of paediatric PAH. Three large patient cohorts were involved in these studies: our national registry for pulmonary hypertension including all Dutch children with PAH, the unique international TOPP-registry with 699 patients from 19 countries and a large international cohort from expert centres in The Netherlands, Denver and New York. The epidemiologic data from this thesis provides new information on the presentation, associated diseases and risk factors of PAH. This data helps to detect the disease in an earlier phase and even screen for the disease in specific risk groups. The current paediatric acute response criteria, used to identify children that qualify for calcium channel blocker therapy, could be rejected based on this thesis. We demonstrated that newer criteria could better identify patients that respond well to calcium channel blocker therapy. Hereby the right patients can be selected for calcium channel blocker therapy and PAH-targeted therapy is not wrongly withheld for false responders. Furthermore, we provided the first evidence that add-on therapy is effective in children with PAH and that combination therapy improves outcome compared to mono-therapy. Also, we could identify parameters that can predict outcome of children with PAH and that can serve as treatment targets. Therefore this thesis provides a scientific basis for an aggressive treatment strategy for children with PAH, that can improve outcome for these children