The study, by a team at Washington University School of Medicine, St. Louis, conducted cardiac ultrasound on 168 children ages 10 to 18 to check on symptoms such as heart murmur, chest pain, acid reflux or high blood cholesterol.
A new tissue Doppler imaging technique called "vector velocity imaging" was used to track the movement of the heart's muscular wall.
Of the children, 33 were obese, 20 were at risk for obesity, and 115 were normal weight. The researchers found that the rate of motion of heart muscle changed in the patients who are obese.
With every increase in child's BMIA (body mass index for age), alterations were seen in both the relaxation and contraction phase of the heartbeat.
Dr. Angela Sharkey, an associate professor of pediatrics at Washington University School of Medicine said, "Many of these changes that have been seen in adults were assumed to be from long-standing obesity, but it may be that these changes start much earlier in life than we thought."
"Based on this study, these subtle markers can help us predict who could be at risk for heart disease and heart attacks," Sharkey added.
According to the U.S. Centers for Disease Control and Prevention, about 19 percent of American children ages 6 to 11 and 17 percent of those ages 12 to 19 are overweight.
Researchers say further studies are need to see if interventions, such as dietary changes, increased exercise, and the use of cholesterol-lowering statin drugs have any effect on the obese kids.
The findings were published in the winter issue of the Journal of Cardiometabolic Syndrome.
