Background
Once considered by the ancient Greeks as inert conduits within which air flowed, William Harvey is generally credited with being the first to describe the circulation of the blood through arteries. When the heart contracts it generates a pulse or energy wave that travels through the circulation. The speed of travel of this pulse wave (pulse wave velocity or PWV) is related to the stiffness of the arteries. Other terms that are used to described the mechanical properties of arteries include elastance, or the reciprocal (inverse) of elastance, compliance. The relationship between arterial stiffness and pulse wave velocity was first predicted by Thomas Young in his Croonian Lecture of 1808 but is generally described by the Moens–Korteweg equation or the Bramwell–Hill equation. Typical values of PWV in the aorta range from approximately 5 m/s to >15 m/s.
Measurement of aortic PWV provides some of the strongest evidence concerning the prognostic significance of large artery stiffening. Increased aortic PWV has been shown to predict cardiovascular, and in some cases all cause, mortality in individuals with end stage renal failure, hypertension, diabetes mellitus and in the general population. However, at present, the role of measurement of PWV as a general clinical tool remains to be established. Devices are on the market that measure arterial stiffness parameters (augmentation index, pulse wave velocity). These include the Complior, CVProfilor,PeriScope, Hanbyul Meditech, Mobil-O-Graph NG, Pulsecor, PulsePen, BPLab Vasotens, Arteriograph and SphygmoCor.
Read more about this topic: Arterial Stiffness
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