P2.010: Echocardiographic Assessment of Cardiac Growth in Children with Structurally Normal Hearts

Background: Early childhood is a critical window for cardiac development, yet the impact of prenatal factors and early growth patterns on heart structure and function in healthy children remains underexplored. This study investigates the roles of birth weight (BW), gestational age (GA), birthweight-for-gestational-age (BW/GA) z-score, and weight gain z-score in shaping cardiac dimensions, aiming to clarify the impact of both perinatal factors and postnatal weight gain on cardiac development in a healthy pediatric population.

Methods: In this longitudinal study we analyzed 1,000 echocardiograms from 738 healthy children aged 11 to 83 months. We measured various cardiac structures, including the aortic root, ascending aorta, left ventricular internal diameter, left ventricular mass, and functional indices such as ejection fraction and fractional shortening. Z-scores for cardiac dimensions and volumes were used to standardize for body surface area (BSA). BW, BW/GA z-score, GA, and weight gain z-score (calculated as weight-for-age (WFA) z-score minus BW/GA z-score) were analyzed as predictors of these parameters.

Results: Higher weight gain z-score was independently associated with smaller cardiac dimension z-scores, particularly in the aortic root, ascending aorta, left ventricular internal diameter at end-diastole, left ventricular internal diameter at end-systole, end-systolic volume, end-diastolic volume, and left ventricular mass. While birth characteristics influenced some cardiac parameters, postnatal growth trajectories emerged as more significant predictors of cardiac size. Ejection fraction and fractional shortening, as functional indices of myocardial performance, were not influenced by the predictors in our analysis.

Conclusion: Our findings suggest that postnatal weight gain plays a more critical role than prenatal factors in shaping cardiac dimensions in healthy children. While GA and BW/GA z-score had some influence, postnatal growth trajectories emerged as stronger determinants of cardiac size. Specifically, greater changes in postnatal weight gain during early childhood were associated with disproportionately smaller cardiac dimension z-scores in aortic root, ascending aorta, and some left ventricular structures. These findings underscore the importance of monitoring postnatal growth patterns and suggest that early interventions targeting rapid weight gain may be crucial for optimizing long-term cardiovascular health.