Screening for Subclinical Coronary Artery Disease Measuring Carotid Intima Media Thickness

Traditional coronary risk assessment is based on major cardiovascular risk factors using the Framingham risk score. Carotid intima-media thickness (CIMT) measured by ultrasonography is a noninvasive test used to assess for the presence of coronary atherosclerosis. CIMT has been shown to be an independent predictor of future cardiovascular events and is used in research trials as a surrogate for the presence as well as regression of coronary artery disease. The objectives of this report are to review the published reports on CIMT and to help establish the role of CIMT as a screening tool for coronary artery disease in selected patients. CIMT measurement can modify cardiovascular risk prediction in patients initially classified with the Framingham risk score, with reclassification into higher or lower risk categories. It is most useful for refining risk assessment in patients at intermediate risk. The Screening for Heart Attack Prevention and Education (SHAPE) Task Force recommends screening all asymptomatic middle-aged and older men and women using noninvasive imaging. The American Society of Echocardiography established a consensus on the methodologic aspects of CIMT measurement. Sequential scanning of CIMT to assess atherosclerosis is currently not recommended, because of interscan variability and small expected changes over time. In conclusion, in the primary prevention of coronary artery disease, CIMT measurement reclassifies patients into higher or lower risk categories, allowing early appropriate management.