To be able to design goal-oriented treatment strategies in paediatric pulmonary arterial hypertension (PAH), we aimed to identify treatment goals by investigating the prognostic value of treatment-induced changes in noninvasive predictors of transplant-free survival.66 consecutive, treatment-naïve paediatric PAH patients in the Dutch National Network for Paediatric Pulmonary Hypertension who started taking PAH-targeted drugs between January 2000 and April 2013 underwent prospective, standardised follow-up. Clinical, biochemical and echocardiographic measures were longitudinally collected at treatment initiation and follow-up, and their respective predictive values for transplant-free survival were assessed. Furthermore, the predictive values of treatment-induced changes were assessed.From the identified set of baseline predictors, the variables World Health Organization functional class (WHO-FC), N-terminal pro-brain natriuretic peptide (NT-proBNP) and tricuspid annular plane systolic excursion (TAPSE) were identified as follow-up predictors in which treatment-induced changes were associated with survival. Patients in whom these variables improved after treatment showed better survival (p<0.002).Therefore, WHO-FC, NT-proBNP and TAPSE are not only predictors of transplant-free survival in paediatric PAH but can also be used as treatment goals, as treatment-induced improvements in these variables are associated with improved survival. The identification of these variables allows for the introduction of goal-oriented treatment strategies in paediatric PAH.

Background and aims: The Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension (TOPP) registry is a global network established to gain insights into the disease course and long-term outcomes of paediatric pulmonary arterial hypertension (PAH). Previously published cohorts in paediatric PAH are obscured by survival bias due to the inclusion of both prevalent (previously diagnosed) and incident (newly diagnosed) patients. The current study aims to describe long-term outcome and its predictors in paediatric PAH, exclusively of newly diagnosed patients. Methods and results: Five hundred thirty-one children with confirmed pulmonary hypertension, aged ≥3 months and <18 years, were enrolled in the real-world TOPP registry at 33 centres in 20 countries, from 2008 to 2015. Of these, 242 children with newly diagnosed PAH with at least one follow-up visit were included in the current outcome analyses. During long-term follow-up, 42 (17.4%) children died, 9 (3.7%) underwent lung transplantation, 3 (1.2%) atrial septostomy, and 9 (3.7%) Potts shunt palliation (event rates: 6.2, 1.3, 0.4, and 1.4 events per 100 person-years, respectively). One-, three-, and five-year survival free from adverse outcome was 83.9%, 75.2%, and 71.8%, respectively. Overall, children with open (unrepaired or residual) cardiac shunts had the best survival rates. Younger age, worse World Health Organization functional class, and higher pulmonary vascular resistance index were identified as independent predictors of long-term adverse outcome. Younger age, higher mean right atrial pressure, and lower systemic venous oxygen saturation were specifically identified as independent predictors of early adverse outcome (within 12 months after enrolment). Conclusion: This comprehensive analysis of survival from time of diagnosis in a large exclusive cohort of children newly diagnosed with PAH describes current-era outcome and its predictors.

Prognosis in children with pulmonary vascular disease (PVD) is closely linked to right ventricular (RV) failure due to increased RV-afterload. Pulmonary arterial (PA) stiffening is known to occur early in the course of PVD and constitutes a main component of RV-afterload. This study aimed to evaluate the clinical value of PA-stiffness in children with PVD by determining its association with advanced pulmonary arterial hypertension (PAH) and mortality at long-term follow-up. Forty-one children with various stages of arterial PVD, defined as mean PA-pressure ≥20 mmHg and/or pulmonary-to-systemic flow-ratio ≥1.2, and mean pulmonary capillary wedge pressure <15 mmHg, underwent cardiac catheterization with intravascular ultrasound (IVUS) imaging between 1994 and 1997 with follow-up until 2015. PA-stiffness indices evaluated were PA-area-compliance (PA-compliance) and PA-area-distensibility (PA-distensibility). During follow-up, advanced PAH was determined by echocardiography and cardiac catheterization. During a median follow-up of 19 years, in 31 (76%) patients PVD had reversed and 10 (24%) had advanced PAH. Six (15%) died due to PVD. In addition to conventional haemodynamics, PA-compliance and PA-distensibility were associated with advanced PAH at long-term follow-up (adjusted OR [95% CI] 0.56 [0.37–0.85] and 0.52 [0.31–0.86]), and mortality (adjusted HR [95% CI] 0.60 [0.41–0.87] and 0.67 [0.49–0.90]). Also in a subgroup of patients with favourable haemodynamics, baseline PA-compliance and PA-distensibility were lower in patients with advanced PAH at follow-up (P = 0.002 /P = 0.030). In children with PVD, PA-stiffness indices assessed by IVUS predict advanced PAH and mortality at long term follow-up. Especially in patients with favourable haemodynamics, assessment of intrinsic PA-stiffness may enhance the prognostication of disease progression and survival.