Non-invasive Assessment of Vascular Function
There are new ways to measure the function of the arteries in the body without using needles or X-rays. These 'non-invasive' methods include ultrasound of the carotid artery along with measurement of brachial distensibility, aortic augmentation index and pulse wave velocity to the arm, leg and foot arteries. With these new instruments, we can tell if an individual is developing hardening of the arteries, a risk factor for heart attack, stroke and progression of kidney disease. Abnormalities in these measurements are also associated with elevation in CV risk factors like blood pressure, cholesterol and diabetes. Doctors can then treat the risk factors in an effort to get the function of the arteries to improve.
These techniques are now demonstrating useful in studies of children. The thickness of the carotid artery with ultrasound was found to be higher in children with overweight or high blood pressure. This may put children at risk of stroke and indicates an urgent need for treatment. Brachial artery distensibility is abnormally reduced in overweight children especially those that have a high insulin level, a pre-diabetic condition. Augmentation Index is abnormally elevated in children with type I diabetes and childhood blood pressure predicts abnormally elevated PWV later in life. Therefore, non-invasive measures of vascular function can be used to identify children at high risk of later cardiovascular disease so preventive treatment can be started early in life.
References
Sorof JM, Alexandrov AV, Garami Z, Turner JL, Grafe RE, Lai D, Portman RJ. Carotid ultrasonography for detection of vascular abnormalities in hypertensive children. Pediatric Nephrology. 2003;18:1020-4.
Urbina EM BJ, Daniels SR, Dolan LM. Overweight and Insulin Resistance Provide Individual Contributions to Compromises in Brachial Artery Distensibility in Healthy Adolescents. Diabetes. 2005;54 (suppl 1):A52 (abstract 208-OR).
Haller MJ, Samyn M, Nichols WW, Brusko T, Wasserfall C, Schwartz RF, Atkinson M, Shuster JJ, Pierce GL, Silverstein JH. Radial artery tonometry demonstrates arterial stiffness in children with type 1 diabetes. Diabetes Care. 2004;27:2911-7.
Li S, Chen W, Srinivasan SR, Berenson GS. Childhood blood pressure as a predictor of arterial stiffness in young adults: the bogalusa heart study. Hypertension. 2004;43:541-6.
For more information about the Cardiovascular Imaging Core Research Laboratory at Cincinnati Children's, please contact Thomas R. Kimball, MD, (tkimball@cchmc.org) 513-636-8270 or Sandra A. Witt, RDCS, FASE, (sandy.witt@cchmc.org) 513-636-7409.
