Insight Into Normal Mitral and Tricuspid Annular Dynamics in Pediatrics: A Real-time Three-dimensional Echocardiographic Study

MV area change differs from adults, which may be explained by a more compliant myocardium in children. Greater lateral forces on TV 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.