Active right atrial emptying fraction predicts reduced survival and increased adverse events in childhood pulmonary arterial hypertension

Abstract Background Right atrial (RA) function has been studied rarely in childhood pulmonary arterial hypertension (PAH). We sought to determine if RA and right ventricular (RV) area changes measured by echocardiography predicted outcomes. Methods We reviewed data from children with PAH undergoing cardiac catheterization and echocardiography. RA and RV areas were obtained from the apical 4-chamber view. Clinical worsening indicated initiation of parenteral prostanoid therapy, heart and/or lung transplantation, Potts shunt surgery or death. Results We studied 57 children (27 females), median age 3 years (range 0.30–17 years), body surface area 0.56 m2 (0.2–1.8), follow up 3 years (0.21–8.35), time to clinical worsening was 1.14 years (0.03–6.14) and mortality was 1.55 years (range 0.88–4.95). We determined from receiver operator curves that RA active emptying fraction (RA EaF) ≥60% predicted clinical worsening (sensitivity 78%, specificity 69%, AUC 0.7) and mortality (sensitivity 100%, specificity 65%, AUC 0.82). RV fractional area change (RVFAC) Conclusion In childhood PAH, RA EaF ≥ 60% and RVFAC