Evaluation Of Left Ventricular Strains In Healthy Infants、Children And Adolescents By Three-dimensional Speckle Tracking

ObjectiveThis study was performed to evaluate the characteristics of left ventricular systolic longitudinal strain,radial strain and circumferential strain in healthy infants, children and adolescents by three-dimensional speckle tracking (3D-STI). So as to provide basic databases for the evaluation of childrenleft ventricular systolic function of children in clinic conditions by three-dimensional speckle tracking.MethodsOne hundred and twenty-six healthy subjects aged from3days to15years were divided into5groups:GroupA infants(3days-3years old), Group B pre school age children(3-6years old), Group C school age children (6-10years old), Group D preadolescent (10-13years old) and Group E adolescent age(13-15years old). The dynamic images of apical two-chamber views and four-chamber views were displayed and apical full-volume acquisition was obtained in126subjects to visualize the whole left ventricular in a volumetric imagine. The full-volume imagines were recorded and then were analyzed by on-line3D-STI analysis software. The peak longitudinal strains (PLS),peak radial strain(PRS),peak circumferential strain(PCS) of the global left ventricular and the16segments by using3D-STI can be got and then the values of the above parameters was compared between different groups.Results1Comparision in the groups①The PLS value of apical segment was larger than the basal one and the middle one, and it has a decreasing trend from the apical segment to the basal segment. And the difference was statistically significant (P<0.05);②The difference of the PRS value in the apical segment, the middle segment and the basal segment was statistically significant (P<0.05); the PRS value of the middle segment is larger than the apical one.③The difference of the PCS value in the apical, the middle segment and the basal segment was statistically significant (P<0.05);2Comparision between the groups①The PGLS value of the five groups showed a decreasing trend with age. The PGLS value of Group A、B and C were larger than the one in Group D and E. And this difference was statistically significant (P<0.05);②The difference of the PGRS value of the five groups was not statistically significant (P>0.05);③The PGCS value of the five groups showed an increasing trend with age. The PGCS value of Group E was larger than the one in Group A. And this difference was statistically significant (P<0.05);Conclusion1. The ongitudinal, radial and circumferential strain have their own characteristics in normal children and there are differences in the16segments..And the differences may be related with the myocardial fibers arrangement in different periods and the children’s heart physiological anatomical characteristics. 2. There is heterogeneity of left ventricular myocardial function distribution in different age groups in normal children.And it mainly reflects in young children group and adolescence group. The global strain along with the age has certain law: axial strain decrease with age, circumferential strain increases with age, radial strain has no change along with the age.