Relationship between the pulse wave and the flow velocity wave and their propagation velocities in the arterial system: Implications for the assessment of regional physical properties of the arterial beds

Abstract

The rate of propagation of pressure wave in a thick-walled viscoelastic tube depends on its wall stiffness following the Moens-Korteweg equation. It is hypothesized that pulse and flow waves are closely related and share the same physical principles of transmission.

Twenty human subjects were studied to explore the relationship between the pulse and flow velocity waves in the arterial system. The pulse waves were recorded using the external pulse recorder from the right carotid and femoral arteries. The velocity signals were recorded from the same locations using pulsed wave Doppler technique. The onsets of the pulse and velocity waves correlated very closely in both the carotid and femoral arteries (r = 0.96, p < 0.001 and r = 0.97, p < 0.001 respectively). The carotid to femoral rates of transmission of the pulse and velocity waves, calculated by the foot to foot method, were very closely related (r = 0.98, p < 0.001, SEE = 50 cm/sec).

It is suggested that velocity waves follow the same physical principles of transmission as the pulse or pressure waves and a study of the velocity waves will enable one to assess the elastic properties of the arterial wall as suggested by the Moens-Korteweg equation. In addition, velocity signals can be obtained noninvasively from deeper vessels, potentially allowing assessment of regional elastic properties of different arterial beds. This may allow serial noninvasive monitoring for disease in different arterial segments.