Objective To investigate the reference values and Z scores regression equations of newborn undergoing echocardiography. Methods Two hundred and eighty-eight newborns (aged 0-28 days) of Shenzhen Children′s Hospital underwent echocardiography examination, including M-mode, two-dimensional (2D) and real-time three-dimensional (3D) echocardiography, color Doppler lfow imaging (CDFI) and tissue Doppler imaging. The correlation between echocardiography results and weight were analyzed and Z scores were calculated. Results The normal values of right ventricular diameter (RV) and left ventricular end-diastolic diameter (LVEDD) measured by M-mode, the mitral annulus diameter in four chamber view (MV-D1), mitral annulus diameter in two chamber view (MV-D2), mitral annulus diameter in longitudinal view (MV-D3), aortic ring diameter (ARD), aortic sinus diameter (ASD), ascending aorta diameter (AAO), transverse aorta diameter (TA), aortic isthmus diameter (AI), aorta diaphragm diameter (AO-Dia), tricuspid annulus diameter in four chamber view (TV-D1), tricuspid annulus diameter in right ventricular inlfow tract view (TV-D2), right ventricular outlfow tract diameter (RVOT), pulmonary valve diameter (PVD) and main pulmonary artery diameter (PA) measured by 2D echocardiography and the normal values of mitral valve inflow Doppler component during early diastole (MV-E), mitral valve inlfow Doppler component during atrial contraction (MV-A), tricuspid valve inlfow Doppler component during early diastole (TV-E), tricuspid valve inflow Doppler component during atrial contraction (TV-A), aortic valve peak velocity (AV-max), aortic valve velocity-time integral (AV-VTI), pulmonary valve peak velocity (PV-max), pulmonary valve velocity-time integral (PV-VTI) measured by pulse Doppler, the mitral annular tissue Doppler component during systole (MV-s′), mitral annular tissue Doppler component during early diastole (MV-e′), mitral annular tissue Doppler component during atrial contraction (MV-a′), tricuspid annular tissue Doppler component during systole (TV-s′), tricuspid annular tissue Doppler component during early diastole (TV-e′), tricuspid annular tissue Doppler component during atrial contraction (TV-a′), interventricular septum annular tissue Doppler component during systole (IVS-s′), interventricular septum annular tissue Doppler component during early diastole (IVS-e′), interventricular septum annular tissue Doppler component during atrial contraction (IVS-a′) measured by tissue Doppler, the normal values of left atrial volume (LAV), left ventricular end-systolic volume (LVEDV), stroke volume (SV) and cardiac output (CO) measured by bi-plane method and the normal values of LVEDV, SV and CO measured by real-time tri-plane method, together with the normal values of left ventricular (LV) mass, left ventricular mass index [LV mass/BSA, LV mass/H2.7, body surface area (BSA) and height (H)], all showed nonlinear positive correlations with body weight (all P<0.01). The values of MV-E/A, PV-E/A, MV-e′/a′, TV-e′/a′, IVS-e′/a′, MV-E/IVS-e′, LV mass/LVEDV and left ventricular ejection fraction (LVEF) showed no correlations with body weight (all P>0.05). Except for RV, MV-D1, MV-D2, MV-D3, TV-D1, TV-E, MV-s′, IVS-a′, TV-s′and TV-e′, all R2 obtained by nonlinear regression method (lnY=a+bX+cX2+dX3) were larger than those obtained by linear regression method (Y=a+bX). The Z score showed a normal distribution and no correlation with body weight. Conclusions The normal reference values of newborn undergoing echocardiography reflect the variation in weight. The Z scores can be obtained by the predicted nonlinear regression equations and show standard normal distribution. The echocardiography normal reference values have important significance for the diagnosis and treatment of neonatal heart disease.

Objective To investigate the clinical value of coronary artery Z-scores on echocardiography in diagnosing coronary artery abnormalities. Methods The echocardiography results of 612 patients with Kawasaki disease (KD) at the acute and recovery phase were retrospectively studied. Coronary artery luminal diameters were converted to body-surface-area-adjusted Z-scores. According to coronary Z-scores classiifcation, all the subjects were divided to four groups:415 cases with no dilation (ND), 133 cases with small coronary artery abnormalities (SCAAs), 47 cases with large coronary artery abnormalities (LCAAs), and 17 cases with giant coronary artery abnormalities (GCAAs). Clinical features (gender, age, typical clinical manifestations, fever duration) and laboratory results (CRP, ESR, WBC, PLT) were compared among all the four groups. Coronary artery diameters and the Z-scores were compared between acute and convalescence phase. Results Along with the increase of coronary Z-score, fever duration was prolonged [ND group:(7.75±3.12) d, SCAAs group (8.50±4.12) d, LCAAs group: (8.57±3.58) d, GCAAs group: (11.88±4.33) d, F=22.375, P<0.05]. With coronary Z-score increasing, PLT also increased (F=22.029, P=0.000), and the highest PLT was observed in GCAAs group. There were no significant differences in the CRP, ESR and WBC among all the four groups (F=0.236, 1.116, 0.121, all P>0.05). No significant different coronary diameters were found in ND cases between recovery and acute phase [(2.24±0.34) mm vs (2.33±0.36) mm, t=1.926, P > 0.05]. But there were significant difference in the coronary Z-scores of ND patients between recovery and acute phase (0.41±0.82 vs 1.17±0.75, t=8.332, P < 0.05). The coronary Z-scores in SCAAs group (1.32±0.89 vs 3.40±0.62, t=11.073, P < 0.05), LCAAs group (3.12±2.27 vs 6.20±1.28, t=4.579, P<0.05) and GCAAs group (11.88±6.77 vs 20.4±9.70, t=3.480, P<0.05) at recovery phase were smaller than values at acute phase. Conclusions The KD coronary Z-scores are the body-surface-area-adjusted standard value, and not subject to the influence of children growth and development. Therefore, it may accurately evaluate the severity of coronary artery abnormalities and its recovery process. Accurate quantitative of the coronary artery luminal dimensions is important in KD clinical management and prognosis prediction.