Transit Time Measurement Method by Complex Cross-Spectrum Analysis applied to a variable PWV Arterial Simulator

Pulse Wave Velocity (PWV) is a reliable marker for assessing arterial stiffness and the health of the cardiovascular system. To study under repeatability conditions the relationship between PWV and other hemodynamic quantities, many kinds of arterial simulators are proposed in literature where PWV is estimated by measuring the Pulse Transit Time (PTT) of the pressure wave traveling through the vessels. Over time, several methods have been implemented to assess PTT, among them the wavelet-based approach offers some advantages, nevertheless, in the literature its application to waveforms provided by arterial simulators is still not fully investigated and needs proper validation. In this paper, a method for PTT estimation by wavelet complex cross-spectrum analysis is tested first on simulated waveforms and then on measurement signals acquired from a prototype of an arterial simulator where the PWV can be modified depending on the transmural pressure applied to an arterial surrogate. The results show that the implemented method can be considered a promising tool for the analysis and processing of the pressure waves traveling in the simulator vessel.