Background and Aim Survival after premature birth and neonatal lung disease is nowadays almost universal. To determine the long-term health outcomes for these infants, cardio-respiratory follow-up is needed. Whereas normative reference data for lung function in children exists, reference data of cardiac structure and function are at large lacking. The aim of this study was to determine right heart dimensions, volumes and function in healthy pre-school children using echocardiography. We also wanted to compare right heart dimensions from 2D-images with volumes obtained from 3D-full volume single-beat echocardiographic measurements.
Methods Forty-one healthy children (23 boys) aged 6 years, mean weight=24.1±4.3kg and mean height=121.9±4.3cm, were assessed with echocardiography (Acuson SC2000, Siemens). Using 2D-echocardiography, we measured right ventricular (RVmajor/minor) and right atrial diameters (RA major/minor). Using pulsed waved Doppler tissue imaging we calculated the E/e’-ratio and the Tei-index. With 3D-echocardiography we also calculated volumes for the right ventricle (RVEDV, RVESV) and atrium (RAEDV, RAESV), as well as ejection fraction (EF) for RV.
Results The RVmaj was 53.0±3.7mm, RVmin 29.9±3.1mm, RVEDV 42.8±7.5ml, RVESV 18.9±3.4ml, RAmaj 35.3±3.6mm, RAmin 32.0±3.1mm, RAEDV 6.5±2.4ml, RAESV 15.8±4.3ml, E/e’ratio 3.3±0.7, RV Tei-index 0.36±0.09 and RVEF 56 (range51–61) %. The length of right ventricle (RVmaj) measured with 2D correlated significantly with 3D estimated volumes (RVEDV, r=0.45, p<0.01). Right heart volumes correlated positively with BMI; RVEDV(r=0.61, p<0.001), RVESV(r=0.62, p<0.001), RAEDV(r=0.72, p<0.001) and RAESV(r=0.48, p<0.01).
Conclusion These reference data on right ventricular and atrial dimensions and volumes can be used for follow-up studies of boys and girls at 6-years-of-age. 3D volumes correlated moderately with BMI.