Prognostic significance of 2-dimensional, M-mode, and Doppler echo indices of right ventricular function in children with pulmonary arterial hypertension

Background Echocardiographic measures of right ventricular (RV) function are associated with adverse outcomes in adults with idiopathic pulmonary arterial hypertension (iPAH) but have not been adequately studied in children. We investigated the prognostic value of 2D, M-mode and Doppler indices of RV function in relation to death or lung transplant in children with iPAH and PAH associated with congenital heart diseases (cPAH). Methods Children with iPAH and cPAH were studied. Two echocardiograms were analyzed for each patient: at diagnosis and at last follow-up. Clinical data, catheter hemodynamics and 6-minute walk distance were recorded. Echo indices of RV function were compared between the first and follow-up echo, between iPAH and cPAH patients, and between iPAH patients alive at follow-up versus those who had died or had undergone lung transplant. Survival probability stratified by RV function was analyzed. Results Fifty-four children were studied: 36 cPAH patients (7.5 +/- 5.9 years) and 18 iPAH patients (8.9 +/- 5.7 years) of whom 12 were alive and 6 had died or were transplanted. Despite similar pulmonary hemodynamics, RV function, including right atrial volume, tricuspid annular planar excursion, fractional area of change, and left ventricular eccentricity index were worse in iPAH at presentation and at follow-up. At last echo there was further worsening of RV function in iPAH patients, particularly in those who had died or were transplanted, compared with improved or unchanged indices in cPAH patients or iPAH survivors. Conclusion Conventional echo RV functional parameters are valuable to identify risk for transplant or death in children with PAH.