flow-mediated dilation
A non-invasive ultrasound technique measuring endothelial function by assessing arterial dilation following reactive hyperemia.
Full Definition
Flow-mediated dilation (FMD) is a non-invasive vascular imaging technique that assesses endothelial function by measuring the percentage increase in arterial diameter following induced reactive hyperemia. The test typically involves occlusion of the brachial artery for five minutes followed by release, with subsequent measurement of arterial dilation using high-resolution ultrasound. Normal FMD responses range from 5-15%, with reduced values indicating endothelial dysfunction. This technique serves as a surrogate marker for coronary endothelial function and cardiovascular risk assessment, particularly valuable in research settings and early detection of atherosclerotic disease.
Usage
Usage note: Expressed as a percentage; higher values indicate better endothelial function.
In Context
- "Flow-mediated dilation was impaired at 3.2%, suggesting significant endothelial dysfunction." — Vascular function study report
- "The research protocol included FMD assessment to evaluate the effects of statin therapy on endothelial function." — Clinical trial methodology