Intima-Media Thickness (IMT)
Intima-media thickness (IMT) is defined by the measurement of a component of the walls of muscular arteries (intima) by specific modalities of ultrasound, at defined locations in the human body. Intima-media thickness of the carotid artery has been the location most consistently associated with risk of atherosclerotic risk. Because ultrasounds of the carotid artery can be performed safely, at low risk (no ionizing radiation) and with a relatively high degree of reproducibility, IMT has been a common surrogate endpoint in epidemiologic studies and in clinic trials.
Carotid IMT (CIMT) is correlated with other vascular risk factors and is considered an “intermediate phenotype” of early atherosclerosis that independently predicts vascular events. In general, greater CIMT values are associated with greater cardiovascular risk. However, an absolute definition of abnormal CIMT has been problematic due to the effects of age and hypertension on CIMT, independent of their...
References and Readings
- Chambless, L. E., Heiss, G., Folsom, A. R., Rosamond, W., Szklo, M., Sharrett, A. R., et al. (1997). Association of coronary heart disease incidence with carotid arterial wall thickness and major risk factors: The Atherosclerosis Risk in Communities (ARIC) study, 1987–1993. American Journal of Epidemiology, 146, 483–494.PubMedCrossRefGoogle Scholar
- Mark Helfand, D. I., Buckley, M. F., Rongwei, Fu, Rogers, K., Fleming, C., & Humphrey, L. L. (2009). Emerging risk factors for coronary heart disease: A summary of systematic reviews conducted for the U.S. Preventive Services Task Force. Annals of Internal Medicine, 151, 496–507.PubMedGoogle Scholar
- Redberg, R. F., Vogel, R. A., Criqui, M. H., Herrington, D. M., Lima, J. A. C., & Roman, M. J. (2003). Task force #3-what is the spectrum of current and emerging techniques for the noninvasive measurement of atherosclerosis? Journal of the American College of Cardiology, 41, 1886–1898.PubMedCrossRefGoogle Scholar