Assessing pre-clinical ventricular dysfunction in obese children and adolescents: the value of speckle tracking imaging

Abstract

Obesity has become a major health problem worldwide. Cardiovascular abnormalities have been described not only in obese adults but also in obese children and adolescents. The aim of the present study was to investigate left and right, systolic and diastolic ventricular dysfunction in obese paediatric patients without comorbidities using 2D speckle tracking longitudinal strain. Doppler echocardiogram was performed on 50 obese children and adolescents with body mass index (BMI) above the 95th percentile (OG) and 46 non-obese sex- and age-matched controls (CG). Systolic and diastolic functions of both ventricles were investigated through conventional Doppler echocardiography. Tissue Doppler imaging (TDI), colour Doppler myocardial imaging (CDMI), and two-dimensional (2D) speckle tracking were also used to analyse ventricular performance in both groups. Left-ventricular (LV) ejection fraction was similar between groups (68.2 ± 6.2 vs. 68.3 ± 5.3, P = 0.931). Left-ventricular diastolic parameters did not differ between groups, except for a lower mitral A wave (61.6 ± 13.0 vs. 51.9 ± 10.0 cm/s, P > 0.001) and higher E/A ratio (1.8 ± 0.5 vs. 2.1 ± 0.4, P = 0.007) in the controls. Left-ventricular global strain was lower in the OG by both methods (CDMI: 22.0 ± 2.8 vs. 24.6 ± 2.7%, P = 0.020; 2D speckle tracking: 18.4 ± 1.6 vs. 20.4 ± 1.7%, P < 0.001). In multivariate analysis, 2D longitudinal global strain correlated negatively with BMI, r = -0.433, p = 0.002. Although EF was not different between the two groups, LV 2D speckle tracking longitudinal strain was lower in the obese group, even in the absence of other comorbidities, indicating that obesity effects on LV function is an early finding in obesity.