Abstract 14979: Endostatin as a Predictor of Severity and Survival in Pediatric Congenital Heart Disease Associated Pulmonary Hypertension

Abstract

Introduction: Pediatric pulmonary arterial hypertension (PAH) is a multifactorial pulmonary vascular disease with high mortality. Endostatin (ES), an angiogenic inhibitor, is associated with disease severity and mortality in adults with PAH and poor lung growth in children. Hypothesis: Increased ES is associated with worse disease severity and outcomes in pediatric PAH. Methods: Serum ES levels were measured in two cohorts of pediatric PAH (IPAH, FPAH and APAH) patients; the cross-sectional CCHMC PAH Biobank (PAHB, N=175) and a longitudinal cohort from Children’s Hospital of Colorado (CHC, N=61). Outcomes included medical therapy, functional and hemodynamic measures, and survival (death, transplant, palliative shunt). Adjusted logistic and linear regressions and Kaplan-Meier analysis were used to assess the relationship between ES and clinical outcomes. Results: In both cohorts, ES was significantly higher in PAH associated with congenital heart disease (APAH-CHD, PAHB n=70, p=0.002; CHC n=29, p=0.007) and was highest in those with a ventricular shunt (n=24, p=0.001). In APAH-CHD, ES was associated with a decreased 6MWD (-108m, -187- -30, p=0.01) and increased mean right atrial pressure (mRAP 1.8mmHg, 0.3-3.3, p=0.02). Longitudinally, in the APAH-CHD subgroup when adjusted for age, sex, and multiple time points, higher ES was associated with increased PVRi and mPAP (PVRi 2.5WU*m 2 , 0.7-4.3, p=0.007; mPAP 10mmHg, 4.5-15, p<0.001). Kaplan-Meier analysis (Figure 1) demonstrated that ES was associated with worse outcomes in both cohorts, with an adjusted Cox proportional hazard ratio of 4.3 (1.13-16, p=0.03) in the PAHB. Conclusions: ES was associated with worse functional measures, pulmonary vascular hemodynamics, and survival in pediatric APAH-CHD. These observations suggest that serum ES could act as a pulmonary vascular specific biomarker to identify those who are at increased risk of developing PAH and predict poor outcomes in APAH-CHD.