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Updated: Mar 21, 2026
Transthoracic Speckle Tracking Echocardiography for the Quantitative Assessment of Left Ventricular Myocardial Deformation
Published on: October 20, 2016
Pediatric Reference Values and Z Score Equations for Left Ventricular Systolic Strain Measured by Two-Dimensional
Frederic Dallaire1, Cameron Slorach2, Timothy Bradley2
1Division of Pediatric Cardiology, Faculty of Medicine, University of Sherbrooke, and Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada.
Insights
Pediatric myocardial strain measurements are influenced by body size. This study provides Z score equations for left ventricular strain, normalized for body surface area, to improve clinical accuracy in children.
Area of Science:
- Pediatric Cardiology
- Echocardiography
- Cardiac Physiology
Background:
- Myocardial strain measurements in children are affected by cardiac size and growth.
- Lack of pediatric reference values hinders clinical application of strain analysis.
- Need for reliable normal values for left ventricular (LV) strain in healthy children.
Purpose of the Study:
- Determine reference values for LV systolic circumferential and longitudinal strain in healthy children.
- Develop Z score equations for pediatric LV strain, accounting for body size.
Main Methods:
- Recruited 233 healthy children aged 1-18 years.
- Measured LV systolic longitudinal and circumferential strain using 2D speckle-tracking.
- Normalized strain values for body size using nonlinear regression; analyzed associations with body size and Z score distribution.
Main Results:
- Weak but significant nonlinear associations found between body size (BSA superior to age, height, weight) and most strain values.
- Second-order polynomial relationship observed between most strain values and body surface area (BSA).
- Computed Z score equations with adequate normal distributions and no residual BSA association for most strain parameters.
Conclusions:
- Body size significantly influences LV circumferential and longitudinal systolic strain in pediatric echocardiography.
- Presented Z scores are normalized to BSA and adjusted for heteroscedasticity.
- Normalized values may reduce misclassification risk due to normal variations in myocardial strain during growth.
Background:
In pediatric echocardiography, myocardial strain measurements are likely influenced by cardiac size and growth in healthy children. The application of this technique in clinical practice has been hampered by the lack of good normal reference values for the pediatric population. The aim of this study was to determine reference values and Z score equations for left ventricular systolic circumferential and longitudinal strain in a healthy pediatric population.
Methods:
Two hundred thirty-three healthy subjects 1 to 18 years of age were prospectively recruited. Left ventricular systolic longitudinal and circumferential strain measurements were recorded using two-dimensional speckle-tracking. Normalization for body size was performed using parametric nonlinear regression modeling. Several analyses were performed to detect potential residual associations with body size, residual heteroscedasticity, or departure from an adequate Z score distribution.
Results:
There were weak but statistically significant nonlinear associations between body size and most strain values. Body surface area was superior to adjust for body size compared with age, height, and weight. Most strain values displayed a second-order polynomial relationship with body surface area. Z score equations were computed with adequate normal distributions and without residual associations in relation to BSA for most strain parameters.
Conclusions:
There was a weak but significant influence of body size on most left ventricular circumferential and longitudinal systolic strain parameters used in pediatric echocardiography. Z scores are presented for strain measurements normalized to body surface area and adjusted for heteroscedasticity. The use of these normalized values may reduce the risk for misclassification caused by normal variation in myocardial strain values during growth.
