Echocardiographic Normal Reference Ranges for Non-invasive Myocardial Work Parameters in Pediatric Age: Results From an International Multi-Center Study

Abstract

AimsThis international multi-center study aimed to demonstrate the feasibility and reliability of non-invasive myocardial work (MW) parameters in the pediatric population, and to provide normal reference ranges for this useful echocardiographic tool in this specific subset of patients.Methods and ResultsIn this retrospective multi-center study involving three pediatric laboratories, 150 healthy children and adolescents (mean age of 10.6 ± 4.5, 91 males) were enrolled. A complete echocardiographic examination has been performed, including global longitudinal strain (GLS) assessment. The following parameters of non-invasive MW have been obtained through a dedicated software: global work index (GWI), global constructive work (GCW), global work waste (GWW), and global work efficiency (GWE), using left ventricular (LV) strain loops and non-invasive brachial artery cuff pressure values. The lowest expected values were for GWI 1,723 mmHg% in males and 1,682 mmHg% in females, for GCW 2,089 and 2,106 mmHg%, for GWE 95.9 and 95.5% whereas the highest expected value for GWW was 78 mmHg% in men and 90 mmHg% in women. The univariable and multivariable analysis showed significant associations between either GWI or GCW with SBP (β coefficient = 0.446, p < 0.001; β coefficient = 0.456, p < 0.001, respectively) and LV GLS (β coefficient = −0.268, p = 0.001; β coefficient = −0.233, p = 0.003, respectively). Inter- and intra-observer variability showed good reproducibility of non-invasive MW parameters.ConclusionNon-invasive MW parameters were feasible and reliable in the pediatric population. This study provided normal reference ranges of these useful echocardiographic indices.

Normal ranges of non-invasive left ventricular myocardial work indices in healthy young people

“…In the meantime, our results confirmed but also extended previously published findings. We elucidated no influence of age, sex, BMI, HR, mitral annulus e , LVMI, LV sizes or LVEF on GMW indices in young people, in accordance with the previous reports across the different age groups (10,12,13,22). Interestingly, our study showed that SBP increased with age, whereas LV GLS decreases slightly with age in young people, which was in line with previous studies (22,24).…”

“…We elucidated no influence of age, sex, BMI, HR, mitral annulus e , LVMI, LV sizes or LVEF on GMW indices in young people, in accordance with the previous reports across the different age groups (10,12,13,22). Interestingly, our study showed that SBP increased with age, whereas LV GLS decreases slightly with age in young people, which was in line with previous studies (22,24). As the input variables for determining GMW indices, this inverse trend between SBP and LV GLS might explain the independence of GMW parameters from age.…”

“…To date, only three similar studies were conducted regarding the normal ranges of GMW in healthy young people (12,13,22). Specifically, the values of LV GMW indices including GWI, GCW, GWW, and GWE in Pham's study (12) with 81 Asian healthy adolescents (age 10-21 years) were quite similar to our data.…”

“…Specifically, the values of LV GMW indices including GWI, GCW, GWW, and GWE in Pham's study (12) with 81 Asian healthy adolescents (age 10-21 years) were quite similar to our data. However, the other two studies showed slightly higher mean values of GWI and GCW in Western children and adolescents (13,22). In addition, the mean GWW in our study was similar to the result (69 ± 46 mmHg%) from an international multi-center study in pediatric population (mean age of 10.6 ± 4.5 years, 61% males) (22), while lower than that in Tretter's study (84 ± 28 mmHg%) with 52 healthy adolescents (age 11-19 years, 62% males) (13).…”

“…However, the other two studies showed slightly higher mean values of GWI and GCW in Western children and adolescents (13,22). In addition, the mean GWW in our study was similar to the result (69 ± 46 mmHg%) from an international multi-center study in pediatric population (mean age of 10.6 ± 4.5 years, 61% males) (22), while lower than that in Tretter's study (84 ± 28 mmHg%) with 52 healthy adolescents (age 11-19 years, 62% males) (13). The differences of LV GMW indices between studies maybe contributed to the ethnic difference and different levels of image quality.…”