Intima–media thickness

Measurement of the thickness of artery walls

Intima–media thickness (IMT) is a measurement of the thickness of the two innermost layers of the artery wall, the tunica intima and the tunica media. It is commonly used as a surrogate marker for atherosclerosis and cardiovascular disease risk assessment.

Structure

Structure of an artery wall

The arterial wall is composed of three layers: the tunica intima, tunica media, and tunica adventitia. The intima is the innermost layer, consisting of a single layer of endothelial cells and a subendothelial layer. The media is the middle layer, composed primarily of smooth muscle cells and elastic tissue, providing structural support and elasticity to the artery.

Measurement

IMT is typically measured using ultrasound imaging, particularly B-mode ultrasound, which provides a cross-sectional view of the artery. The measurement is usually taken at the common carotid artery, as it is easily accessible and provides a reliable indicator of systemic atherosclerosis.

Clinical Significance

Increased IMT is associated with a higher risk of myocardial infarction, stroke, and other cardiovascular events. It is used as a non-invasive method to assess the extent of atherosclerosis and to monitor the effectiveness of interventions aimed at reducing cardiovascular risk.

Factors Affecting IMT

Several factors can influence IMT, including age, hypertension, hyperlipidemia, diabetes mellitus, and smoking. Lifestyle modifications and pharmacological treatments that target these risk factors can lead to a reduction in IMT.

Use in Research and Clinical Practice

IMT is widely used in clinical research to evaluate the impact of various interventions on cardiovascular health. It is also used in clinical practice to identify individuals at high risk for cardiovascular disease, allowing for early intervention and management.

Related pages

• Atherosclerosis
• Cardiovascular disease
• Ultrasound
• Carotid artery