Method. For most structures, each measurement is indexed as measured value ÷ BSA^AE , then converted to a Z-score as (indexed value − reference mean) ÷ reference SD , using the allometric exponent (AE), mean, and SD reported per structure (and, for CT measurements, per cardiac phase). The atrial and ventricular chamber measurements (Cantinotti et al. 2014) instead use that paper's own log-linear model: Z = (ln[measured value] − [intercept + slope × ln(BSA)]) ÷ standard error of the estimate , with intercept, slope, and SEE reported per structure. The echocardiographic valve/vessel fields (Lopez et al. 2017) are entered in mm for consistency with the rest of this tool, then converted to cm internally before applying that paper's coefficients, which were derived in cm. Height/weight, if entered, compute BSA via the Haycock formula (the method used in all four source studies below); BSA can also be entered directly.
Source. Coefficients for the aorta (CT) come from an open-access preprint (CC BY 4.0) of the peer-reviewed study below; coefficients for the pulmonary arteries (CT) are transcribed from the published journal article — verify against the journal versions if you have access. Coefficients for the echocardiographic valve/vessel measurements are transcribed from Table 2 of the published journal article (Lopez et al. 2017) and cross-checked against the paper's own worked clinical example (BSA 0.3 m², mitral valve 4-chamber diameter 11 mm → Z = −1.0). Cardiac-phase timing for those measurements (diastole for AV valve annuli, systole for semilunar valve and arterial diameters) follows the ASE pediatric quantification standard the paper itself cites for measurement technique (Lopez et al. J Am Soc Echocardiogr. 2010;23:465–495). Coefficients for the atrial/ventricular chamber measurements are transcribed from Table 4 of the published journal article (Cantinotti et al. 2014) and cross-checked against that paper's own Table 5 predicted mean and ±2 SD values across all six parameters at BSA 0.30 m² (exact match to 2–3 decimal places).
Not for diagnostic use — professional disclaimer
This tool is intended exclusively for educational and research purposes. The site cannot and does not contain medical/health advice. The information is provided for general informational, research and educational purposes only and is not a substitute for professional advice. THE USE OR RELIANCE OF ANY INFORMATION CONTAINED ON THE SITE IS SOLELY AT YOUR OWN RISK.
Donthula R, Li W, Duvvada A, Dyar D, Uppu SC. Normative computed tomography angiography values of the aortic root, aorta, and aortic arch in children. Eur J Pediatr. 2024 Dec;183(12):5425–5439.
Donthula R, Li W, Kaur H, Adebo DA, Uppu SC. Normative computed tomography angiography values of the main and branch pulmonary arteries in children. Eur J Pediatr. 2024 Mar;183(3):1183–1193 (Epub 2023 Dec 11).
Lopez L, Colan S, Stylianou M, et al; Pediatric Heart Network Investigators. Relationship of echocardiographic Z scores adjusted for body surface area to age, sex, race, and ethnicity: the Pediatric Heart Network Normal Echocardiogram Database. Circ Cardiovasc Imaging. 2017;10(11):e006979.
Cantinotti M, Scalese M, Murzi B, et al. Echocardiographic nomograms for chamber diameters and areas in Caucasian children. J Am Soc Echocardiogr. 2014 Dec;27(12):1279–1292.
