A study that used two-dimensional speckle-tracking echocardiography (2D-STE) to closely examine the hearts of 100 children and teens found changes in cardiac geometry and systolic function resulting from obesity.  Investigators observed thicker left ventricular (LV) walls and an increased LV mass, as well as impaired measures of systolic function, among the obese children when compared with non-obese children.

In the study, published online October 8, 2014 in the Journal of the American College of Cardiology, researchers from the University of Leipzig Heart Center in Leipzig, Germany, performed the 2D-STE on 61 obese children and 40 non-obese children, ages 9 to 16. The subjects were matched in terms of age, sex, and height, but the obese children had significantly higher body-mass index (BMI 31 vs. 19 kg/m²), larger waist circumferences, higher systolic blood pressure, and worse lipid and glucose metabolism parameters.  Researchers also conducted extensive blood chemistry analysis.

Researchers observed unique changes in the shape and function in the hearts of the obese children.  Compared with the non-obese group, the obese children had thicker left ventricular (LV) walls, a 29% larger LV end-diastolic volume, and a 40% larger LV mass. Left atrial (LA) volume, LA volume index, right atrial area, and right ventricular diameter were also significantly larger in the obese children. The differences remained after adjustment for physical development and growth, although the indexed LV systolic and diastolic diameters were similar between the two groups. 

In addition, obese children had significantly higher blood pressure and higher levels of LDL cholesterol, while HDL cholesterol was significantly lower. 

"Children are ideal subjects to observe the effect of obesity on the heart," said the study's lead author Norman Mangner, M.D., of the Heart Center Leipzig. "This is because they are likely free of clinically relevant cardiovascular disease adults may suffer from."

Manger said 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.