[Analysis of prognosis and associated risk factors in pediatric idiopathic pulmonary arterial hypertension].

To analyze the prognosis and associated risk factors of pediatric idiopathic pulmonary arterial hypertension. A total of 119 patients under 18 years of age diagnosed as idiopathic pulmonary arterial hypertension in the Pulmonary Arterial Hypertension Center in Beijing Anzhen Hospital between June 2007 and May 2017 were enrolled in this retrospective study. The clinical informations and follow-up data were collected. The endpoints of follow-up were defined as death or undergoing lung transplantation. Kaplan-Meier survival curve was used to assess the survival,and the COX risk regression model was used to analyze the prognostic risk factors. The mean age at diagnosis was (5.9±4.2) years. For 92 (77.5%) patients, the main reason for visit was decreased activity with shortness of breath after exercise. Seventy patients (58.8%) were in baseline NYHA functional class Ⅲ-Ⅳ and 49 patients (41.2%) were in NYHA functional class Ⅰ-Ⅱ. The mean systolic pulmonary arterial pressure estimated by echocardiography was (90±23) mmHg (1 mmHg=0.133 kPa) . Right heart catheterization was performed in 50 patients. Hemodynamic parameters revealed that the mean pulmonary artery pressure was (66±19) mmHg. Mean right atrium pressure was (8.5±3.4) mmHg. Mean pulmonary vascular resistance index was (17±9) wood·m(2) and the mean cardiac index was (3.4±1.3)L/m(2); 100 patients (84.0%) received targeted therapy in which 55 patients (46.2%) were on monotherapy,40 patients (33.6%) were on dual therapy and 5 patients (4.2%) were on triple therapy. The mean time of follow-up was 22.0 months (0-108 months). During follow-up, 43 patients (36.1%) died and 1 patient received double-lung transplantation. Main causes of death including right heart failure, pulmonary hypertension crisis, asphyxia and massive hemoptysis. The mean survival time from diagnosis was 37.0 months,1-,2-,3-and 5-year survival rates were 86.3%, 72.2%, 51.4%and 37.8% respectively. Survival analysis showed that patients in baseline NYHA functional class Ⅰ-Ⅱ had better prognosis. COX regression analysis showed that NYHA function class, edema, increased total bilirubin and troponin concentration and the pulmonary artery and aorta diameter ratio measured by echocardiogram are risk factors of pediatric IPAH (=2.310, 2.723, 1.066, 1.696, 3.719, 0.028, 0.005, 0.001, 0.024, 0.030) . While the existence of aterial septal defect or patent foramen ovale, using bosentan and phosphodiesterase inhibitors(,) dual or triple therapy were protective factors (=0.563, 0.559, 0.603, 0.682, 0.044, 0.169, 0.076, 0.115, 0.258, 0.220) . In multivariate analysis only edema associated with decreased survival (=2.398, 0.025) . Childhood idiopathic pulmonary arterial hypertension patients are seriously ill at visit. Worse cardiac function classification at visit associate with high mortality. Target therapy including using bosentan, dual or triple therapy can improve survival.