Introduction: The most efficient risk stratification algorithms are expected to deliver robust and indefectible identification of high-risk children with hypertrophic cardiomyopathy (HCM). Here we compare algorithms for risk stratification in primary prevention in HCM children and investigate whether novel indices of biatrial performance improve these algorithms. Methods and Results: The endpoints were defined as sudden cardiac death, resuscitated cardiac arrest, or appropriate implantable cardioverter-defibrillator discharge. We examined the prognostic utility of classic American College of Cardiology/American Heart Association (ACC/AHA) risk factors, the novel HCM Risk-Kids score and the combination of these with indices of biatrial dynamics. The study consisted of 55 HCM children (mean age 12.5 ± 4.6 years, 69.1% males); seven had endpoints (four deaths, three appropriate ICD discharges). A strong trend (DeLong p = 0.08) was observed towards better endpoint identification performance of the HCM Risk-Kids Model compared to the ACC/AHA strategy. Adding the atrial conduit function component significantly improved the prediction capabilities of the AHA/ACC Model (DeLong p = 0.01) and HCM Risk-Kids algorithm (DeLong p = 0.04). Conclusions: The new HCM Risk-Kids individualised algorithm and score was capable of identifying high-risk children with very good accuracy. The inclusion of one of the atrial dynamic indices improved both risk stratification strategies.

Pulmonary hypertension in children with bronchopulmonary dysplasia (BPD-PH) significantly worsens the prognosis. Pulmonary vasodilators are often used in BPD-PH but the short-term outcome of treatment is not well described. The aim of this study was to evaluate BPD-PH children diagnosed beyond 36 weeks postmenstrual age treated with pulmonary vasodilators (sildenafil, bosentan, or both) and to assess the short and long-term effect of oral pulmonary vasodilators treatment. Twenty patients were included in the study. Cardiology evaluation (WHO-FC, NTproBNP, oxygen saturation, pulmonary to systemic pressure ratio PAP/SAP) was performed at diagnosis and after treatment initiation. In the majority of patients improvement in all evaluated factors was observed. No side effects of vasodilators were observed. PH resolved in 10 patients after a mean of 21.4 months of treatment. Six patients died. The number of poor prognostic factors commonly used to assess patients with pulmonary arterial hypertension (PAH) decreased significantly during BPD-PH treatment. The influence of BPD-PH perinatal risk factors on prognosis was considered but was not confirmed. In conclusion, the treatment of BPD-PH with pulmonary vasodilators was well tolerated and led to a clinical improvement with the possibility of discontinuation without recurrence of PH. Prognostic factors used in pediatric PAH risk stratification also seem to be useful in assessing treatment efficacy and prognosis in patients with BPD-PH.