Left ventricular three-dimensional global systolic strain by real-time three-dimensional speckle-tracking in children: feasibility, reproducibility, maturational changes, and normal ranges.

BACKGROUND: Three-dimensional (3D) strain analysis may help overcome the limitations of Doppler and two-dimensional strain analysis for the left ventricle and become the method of choice for left ventricular (LV) systolic function. The aims of this study were to evaluate the feasibility and reproducibility of LV global 3D systolic strain by real-time 3D speckle-tracking echocardiography (STE) in children and to establish their maturational growth patterns and normal values.

METHODS: A prospective study was conducted in 256 consecutive healthy subjects using real-time 3D echocardiography. Full-volume 3D data were acquired using a 3D matrix-array transducer. Three-dimensional LV peak systolic global strain (GS), global longitudinal strain (GLS), global radial strain (GRS), and global circumferential strain (GCS) values were determined using real-time 3D STE.

RESULTS: A total of 228 patients (89%) met the criteria for analysis; 28 (11%) were excluded. The correlations between age and strain variables by real-time 3D STE were poor (R(2) = 0.01-0.05, P < .05). The differences in GLS and GCS among the five age groups were statistically significant but clinically irrelevant. There were no statistical differences in GRS and GS values among the age groups, nor were there statistical differences between the genders for all 3D strain parameters. Intraobserver and interobserver variability ranged from 5.0 ± 4.3% to 10.1 ± 8.5% versus 6.9 ± 6.1% to 17.0 ± 16.2% for coefficients of variation, respectively. Interclass correlation coefficients ranged from 0.78 to 0.87 and from 0.75 to 0.79 for intraobserver and interobserver measurements for GS, GLS, GCS, and GRS, respectively.

CONCLUSIONS: LV global 3D systolic strain analysis using the new 3D STE is feasible and reproducible in the pediatric population. There are small maturational changes in GLS and GCS, but not in GRS and GS, that are statistically significant but probably clinically irrelevant. Further investigation is warranted for potential clinical application of this new technology in a pediatric population.