Long-term Efficacy Of Bosentan In Treatment Of Pulmonary Arterial Hypertension In Chinese Children

Background: Bosentan, an oral endothelin ETA/ETB receptor antagonist, improves hemodynamics and exercise capacity in adults or children with pulmonary arterial hypertension(PAH) in short time; however, limited data are available on its long-term effects in children of china. This study investigated the long-term effectiveness and safety of children with PAH in china treated with bosentan therapy.Methods:In this open and observational study, we screened Chinese children(age<18 years old) from shanghai pulmonary hospital and Beijing fuwai hospital with PAH started bosentan. Before treatment, World Health Organization(WHO) functional class, NT-pro BNP, safety data, echocardiogram indexes and hemodynamic parameters were collected and followed up from July 2007 to June 2013.Results:After 20.7 months with bosentan treatment, in total 39 patients, the WHO functional class of 77.2 percent of patients had no obvious worsen with bosentan treatment. Log NT-pro BNP increased from 2.79±0.93 to 2.89±1.09,but had no significant difference(P=0.528); echocardiogram index: Pulmonary arterial systolic pressure(PASP) decreased from 98.2±24.7mm Hg(1mm Hg = 0.133 k Pa) to 89.6±24.6mm Hg(P=0.021); hemodynamic parameters :mean PAP(PAPm) decreased from 74.7±10.0mm Hg to 68.8±12.1mm Hg(P=0.059); mean right atrial pressure(RAPm) decreased from 9.25±2.02 mm Hg to 4.5±1.32 mm Hg; pulmonary vascular resistance index(PVRi)decreased from 25.2±13.6Wood U·m2 to 20.7±8.8 Wood U·m2(P=0.332); cardiac output(CO) increased from 2.67±1.46 L/min to 4.25±2.15 L/min(P=0.152).Kaplan-Meier survival estimates for the 39 patients were88.3%,73.6%,58.5%,52.6% at 1,2,3 and 4 yrs, respectively. The survival rates of idiopathic PAH(IPAH) and PAH associated with congenital heart disease(had or had not repaired) patients had no obvious diffence(P=0.456). Children were well tolerated to bosentan, with only one patient had appeared the elevated liver enzymes.Conclusion:Bosentan is safety for the long-term treatment of PAH in children,and they had no significant deterioration in cardiac function and may have improved prognosis.