Abstract 18517: Treprostinil Decreases Platelet Microparticles in Pediatric Pulmonary Hypertension

Introduction: Vasodilator therapy has greatly improved Pulmonary arterial hypertension (PAH) prognosis. Increased numbers of circulating microparticles (MPs) are found in adult PAH patients and might correlate with disease severity. Therefore, our purpose was to determine if MPs are upregulated in pediatric PAH, and the impact of vasodilator therapies on MPs count and function. Methods: Population study consisted of 27 patients with Congenital Heart Disease (CHD) and elevated pulmonary vascular resistance (CHD-PAH) or idiopathic PAH (iPAH) with a median age of 6.09 years. Among the 27 patients, 12 of them never received any therapy, 8 received one or two oral vasodilators (bosentan and/or sildenafil) and 6 received a triple therapy associating bosentan, sildenafil and SC-treprostinil. Results: Compared to healthy controls, all circulating MP subpopulations were found higher in untreated PAH patients confirming results of adult PAH patients. No significant differences were found between untreated patients ...