Body surface area was the strongest independent predictor of interventricular septal thickness in healthy school-aged children (β = 2.46 mm, p<0.001), alongside male sex and systolic blood pressure.
Cross-Sectional (n=959)
In healthy school-aged children, interventricular septal thickness is primarily determined by body surface area, suggesting that indexing ST to BSA may improve the accuracy of pediatric cardiovascular screening.
Effect estimate: β = 2.46 mm
p-value: p=<0.001
Abstract Background Interventricular septal thickness (ST) is an important echocardiographic measure for assessing cardiac growth and early hypertrophic changes in children. However, normative data from large pediatric cohorts are limited, and the relative influence of age, sex, systolic blood pressure (SBP) and body surface area (BSA) remains unclear. Purpose We aimed to characterize the distribution of ST in healthy children and identify independent determinants of physiological septal variation. Methods In this prospective cross-sectional study, 959 healthy school-aged children (47.5% female; 8–19 years, mean age 13.34 ± 2.30 years) underwent transthoracic echocardiography as part of a school-based cardiovascular screening program. ST was measured by pediatric cardiologists according to current guidelines. Anthropometric data were collected, and BSA was calculated using the Mosteller formula. Participants with missing data for sex, age, SBP, or ST were excluded. Group differences between females and males were assessed using Student’s t-tests and Fisher’s exact tests. Descriptive statistics included mean, SD, median, and percentiles. Associations with continuous variables were examined using Pearson correlation. Independent determinants of ST were identified using multivariable linear regression including sex, SBP, and BSA. Statistical analyses were performed in RStudio, v4.5.1. Results Mean ST was 7.67 (SD 1.59) mm with a median of 8.0 mm (observed range 2–15 mm). Males had significantly higher ST than females (7.95 ± 1.68 mm vs. 7.38 ± 1.43 mm; p 0.001). The 5th–95th percentiles ranged from 5 to 10 mm (5th: 5 mm; 10th: 6 mm; 25th: 7 mm; 50th: 8 mm; 75th: 9 mm; 90th: 10 mm; 95th: 10 mm). ST correlated positively with BSA (r = 0.49), age (r = 0.34), and SBP (r = 0.31) (all p 0.001). Because age and BSA were strongly correlated (r = 0.71), age was excluded from the regression model. In multivariable analysis, BSA was the strongest independent predictor of ST (β = 2.46 mm, p 0.001), while male sex (β = 0.33 mm, p 0.001) and SBP (β = 0.01 mm, p = 0.002) showed modest additional associations. The model explained 26% of the variance (adjusted R² = 0.26) with no relevant multicollinearity (VIF 1.05–1.29). Conclusion In healthy school-aged children, ST is determined by BSA, while male sex and higher SBP exert modest but additional effects. Although age correlated with ST, this association reflected somatic growth and overlapped with BSA. Given the strong influence of BSA, indexing ST to BSA may improve the accuracy of pediatric cardiovascular screening. The normative percentile data generated from this large cohort provides a practical reference for pediatric echocardiography and may enhance early detection of left ventricular hypertrophy in school-based cardiovascular screening, supporting more effective and targeted preventive cardiology strategies in children.
Eichenseer et al. (Mon,) conducted a cross-sectional in Healthy (n=959). Body surface area (BSA) was evaluated on Interventricular septal thickness (ST) (β = 2.46 mm, p=<0.001). Body surface area was the strongest independent predictor of interventricular septal thickness in healthy school-aged children (β = 2.46 mm, p<0.001), alongside male sex and systolic blood pressure.