[II-S13-02] Current Managements and Treatment Strategies for Pediatric Idiopathic and Heritable Pulmonary Arterial Hypertension in Japan
Keywords:肺高血圧症, von willebrand factor, thrombomodulin
In the last decade, specific targeted therapies have been developed and have improved survival in adult patients with idiopathic pulmonary arterial hypertension. However, there have been limited data as for treatment strategies in children due to a small number of randomized controlled trials. Therefore, a clinical impact of the targeted therapies on prognosis in children with idiopathic and heritable pulmonary arterial hypertension (i/hPAH) has not been well evaluated. The aim of this study is to review survival rate with advanced PAH therapies and to identify the critical prognostic factors in children who are followed-up at single center. Consecutive 81 patients with i/hPAH were enrolled. In our current treatment strategies, epoprostenol infusion is initiated at 1 to 2 ng/kg/min and gradually increased dose by 1 ng/kg/min every 1 month. The target dose in children is usually 20 ng/kg/min to 30 ng/kg/min. The patients with ALK-1 mutation positive and familial history were received epoprostenol, if their NYHA functional class was I or II. Overall, 20 patients expired (25%) and 3 patients performed lung transplantation during follow-up and the 5 year-survival rate was 75% in all study population. The current 5 year-survival rate was 94% and the survival rate was dramatically improved since 1978. We retrospectively evaluated clinical parameters and adverse outcomes. As results, BNP (>300pg/ml), pulmonary vascular resistance index (>25units･m2), pulmonary artery capacitance index (<0.85ml/mmHg/m2), and NYHA functional class (IV) at baseline were potential predictors of cardiac mortality in children. Our result suggested that the prognosis of children with i/hPAH has been improved owing to the combination of specific pulmonary vasodilators, although the treatments in children still depend on results from larger adult studies. Future studies are required for development of treatment strategies for children with i/hPAH.