Assessing Children's Arteries For Heart Disease
Addressing the unprecedented rise of heart disease risk factors in children, the American Heart Association recommends standardizing non-invasive assessment of children’s arteries. The recommendations — published as a scientific statement in Hypertension: Journal of the American Heart Association — apply only to children who are participating in research.
The authors said more investigation is needed before issuing clinical recommendations.
Previous research has found that nearly all children have some degree of fatty streaks in their arteries by age three and atherosclerotic plaque by adolescence. This atherosclerosis process leads to changes in the structure and function of the arteries.
Among the key recommendations:
* Researchers should use ultrasound to measure carotid intima-media thickness (CIMT) — the thickness of the wall of the neck artery — to detect early atherosclerosis in children.
* In addition, flow mediated dilation (FMD) can be used to measure how well the blood vessel contracts and expands in response to changing rates of blood flow.
* Tests to measure calcium deposits in arteries should be restricted to very high risk kids due to radiation exposure from the test.
“A paradigm shift in our thinking about cardiovascular disease needs to occur,” said Elaine Urbina, M.D., director of preventive cardiology at Cincinnati Children’s Hospital and Medical Center and lead author of the statement. “The emphasis should be on prevention from both a population basis and by better identifying high-risk individuals before clinical cardiovascular disease occurs. We believe that a better understanding of vascular changes in children will increase our ability to identify high-risk youth in most need of treatment.”
In the statement, the authors recapped current literature on non-invasive assessment of atherosclerosis in children and adolescents, made recommendations for standardizing tools for research and said they hope to stimulate further research.
The statement covers three areas of assessing arteries: artery structure, artery wall stiffness and endothelial function. The endothelium is the inner lining of a blood vessel.
Carotid intima-media thickness can assess arterial structure and gauge atherosclerosis before symptoms appear. Regular measurements allow charting of changes in vessel walls over time.
“We know that atherosclerosis affects the arterial tree in a non-uniform manner,” said Urbina, a member of the Department of Pediatrics at the University of Cincinnati. “We also believe risk factors may affect the layers of the artery differently or affect different arterial segments.”
Coronary artery calcification scanning also assesses arterial structure but should be restricted to children and youth at the highest risk, such at those with a family history of high cholesterol, type 1 diabetes, chronic kidney disease, Kawasaki disease with aneurysm or post heart transplant.
The authors noted that no gold standard has emerged for measuring artery wall stiffness in children, but they recommend pulse wave velocity — which increases in stiffer arteries — because it’s the most widely tested and acceptable method. Pulse wave velocity measures the speed at which the pulse from a heartbeat travels through the circulatory system.
Proper endothelial function involves expanding and constricting the vessel in response to the body’s increased or decreased need for blood flow. This is accomplished by chemical changes in the lining of the blood vessel. Brachial artery reactivity testing, which measures the rate of blood flow in the upper arm, can assess endothelial function.
“We need to apply these tests to thousands of healthy kids of a variety of ages, races, ethnicities and genders so we can better define ‘normals’ for different ages and body sizes,” Urbina said. “Then we need to explore a variety of diseases with the potential for vascular damage. At that point, we will be able to identify kids with accelerated atherosclerosis.”