Childhood obesity is associated with significant changes in myocardial geometry and function, indicating an early onset of potentially damaging alterations in the myocardium, according to a study published Oct. 8 in JACC: Cardiovascular Imaging. 

The study sought to gain a better understanding of obesity and its association with myocardial structural alterations that may influence cardiac mechanics, and prospectively recruited 61 obese (13.5 ± 2.7 years of age, 46 percent male, SD score body mass index (BMI), 2.52 ± 0.60) and 40 non-obese (14.1 ± 2.8 years of age, 50 percent male, SD score BMI, -0.33 ± 0.83) consecutive, non-selected Caucasian children and adolescents. The authors performed a standardized 2-dimensional (2D) echocardiography examination and 2D speckle-tracking analysis, as well as an analysis of blood chemistry (lipid and glucose metabolism).

Results demonstrated that compared with non-obese children, blood pressure, parameters of glucose metabolism, and low-density lipoprotein cholesterol were substantially increased in obese children, while high-density lipoprotein cholesterol was significantly lower. Compared with non-obese children, obese children were also characterized as having enlarged left- and right-sided cardiac chambers, thicker left ventricular walls, and, as a result, increased left ventricular mass. Despite evidence showing comparable left ventricular ejection fraction, decreased tissue Doppler-derived peak systolic velocity and regional basoseptal strain were found in obese children compared with non-obese children.

Further, the results of the 2D speckle tracking showed that longitudinal (-18.2 ± 2.0 vs. -20.5 ± 2.3, p < 0.001) and circumferential (-17.0 ± 2.7 vs. -19.5 ± 2.9, p < 0.001) strain of the left ventricle was reduced in obese children compared with non-obese children. Additionally, compared with non-obese children, obese children had their diastolic function impaired. Finally, both circumferential strain and longitudinal strain were found to be independently associated with obesity.

“Children are ideal subjects to observe the effect of obesity on the heart,” said lead author Norman Manger, MD, University of Leipzig, Heart Center Leipzig, Department of Internal Medicine/Cardiology, Leipzig, Germany. “This is because they are likely free of clinically relevant cardiovascular disease adults may suffer from.” He adds that moving forward, additional studies are needed to determine if these changes are reversible with weight loss, and to determine the predictive value of these early cardiovascular changes.

Keywords: Weight Loss, Pediatric Obesity, Blood Pressure, Myocardium, Glucose, Lipoproteins, LDL, Cholesterol, Body Mass Index, Stroke Volume, Lipoproteins, HDL, Diastole, Heart Ventricles, Echocardiography