2072
Intima-media thickness (IMT), is a measurement of the thickness of tunica intima and tunica media, the innermost two layers of the wall of an artery.
The measurement is usually made by external ultrasound and occasionally by internal, invasive ultrasound catheters.
IMT is used to detect the presence of atherosclerosis and, track the regression, arrest or progression of disease.
The United States Preventive Services Task Force found no support for its routine use in stratification of risk for people at intermediate cardiovascular risk.
IMT can be measured using external ultrasound in large arteries relatively close to the skin and have the advantage of being non-invasive, comparatively low cost and convenient.
IMT is measured in three locations: in the common carotid artery, typically at one cm proximal to the flow divider, at the bifurcation, and in the internal carotid artery.
IMT measurements of the deeper wall, by ultrasound, are generally considered more reliable than measurements performed on the more superficial wall.
Carotid IMT has shown associations with several risk factors, including type 2 diabetes, familial hypercholesterolemia, high-density lipoprotein cholesterol (HDL-C), triglycerides, rheumatoid arthritis,non-alcoholic fatty liver disease, and air pollution.
Using carotid artery IMT as a surrogate endpoint for evaluating the regression and/or progression of atherosclerotic cardiovascular disease is uncertain.
Although carotid intima-media thickness is strongly associated with atherosclerosis, thickening of the intima-media may not always be due to atherosclerosis.
Intima-medial thickening is complex and depends on a number of factors, including blood pressure, local hemodynamics, shear stress, and circumferential tensile stress.