Insight into normal mitral and tricuspid annular dynamics in pediatrics: A real-time three-dimensional echocardiographic study

Background: Although there are animal or adult studies analyzing annular motion of the mitral valve (MV) or tricuspid valve (TV) separately, there are no data analyzing interaction between the MV and TV, or data from the pediatric population. Methods: A total of 17 healthy children (age 3-15 years) were enrolled in this study. Using real-time 3-dimensional echocardiography, annular area, perimeter, segmental diameter, and bending angle were obtained and analyzed. Results: MV area increased during systole, in contrast to TV area, which decreased.. TV area demonstrated a greater reduction of lateral diameter during systole. Bending motion became most acute in early diastole, which was greater for the TV. Conclusions: MV area change differs from adults, which may be explained by a more compliant myocardium in children. Greater lateral forces on W prevent it from becoming circular, thus, preserving valve competency. Both valves show a bending motion, which becomes most prominent during isovolumic relaxation continuing into early diastole for the TV, suggesting a relationship with torsional forces within the ventricles.