Changes in the Interventricular Septal Curvature in Healthy Full-term Neonates During the First 14 Days of Life.

Abstract

Interventricular septal geometry and motion reflect the interaction between the ventricles, and an abnormal shape and abnormal motion are always regarded as signs of increased right ventricular or pulmonary artery pressure. During the neonatal period, there are profound changes in the cardiac circulation. The aims of this study were to quantitatively analyze neonatal septal deformations under normal physiologic conditions and evaluate the changes in association with the hemodynamic changes occurring during the transitional period. This was a retrospective study of 114 healthy full-term neonates from birth to 14 days of age. Normalized septal curvatures were measured on left ventricular parasternal short-axis views during end diastole and end systole. The interventricular pressure gradient, ratio of ventricular volumes, septal strain, thickness, and some clinical characteristics were assessed, along with the association of these parameters with septal curvature. All 4 normalized septal curvatures were found to have a significant correlation with the trans-septal pressure gradient (TSPG) and the end-diastolic volume ratio of the left and right ventricles (P < .0001). The TSPG had the highest impact on septal curvature, and among the 4 curvatures, the middle end-systolic normalized septal curvature had the highest correlation with the TSPG (r2 = 0.948; P < .0001). There were significant correlations between septal curvature and the interventricular pressure gradient and ventricular volume ratio in healthy full-term neonates. The normalized septal curvatures gradually increased with increasing age and could be good indicators of the hemodynamic changes occurring during the transitional period.