What is FMD?
Vascular endothelial function and FMD
The endothelial covers the vascular lumen and has been recognized as an organ that responds to physical and chemical signals by producing some vasoactive substances. The early detection of endothelial dysfunction(ED) is essential to intervene and prevent its progression as ED is considered as an initial step of atherosclerosis.
Many studies have been reported the relationship between vascular endothelial cells and cardiovascular disease since Furchgott (Nobel prize in medicine awarded in 1998) proved nitric oxide (NO) was the endothelium derived relaxing factor.
Flow mediated dilation (FMD), developed by Celermajer in 1992, is an index of vasomotor function that measures arterial diameter to dilate in response to a shear stress stimulus that produces a NO dependent response (induced by the cuff inflation and then deflation).
FMD can be calculated as follows:
The guidelines for FMD testing were first issued by mainly Western researchers in the JACC in 2002, and the Japanese guidelines for FMD testing were published in Hypertension Research in 2008.
Guidelines for FMD:
- Guidelines for the Ultrasound Assessment of Endothelial-Dependent Flow-Mediated vasodilation of Brachial Artery. Corretti MC, Anderson TJ, et al, J.Am.Coll. Cardiol. 2002;39:257-265.
- Flow-Mediated Vasodilation as a Diagnostic Modality for Vascular Failure. Inoue T, Matsuoka H, et al: Hypertension Research 2008;31:2105-2113.
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