A novel non-invasive method for estimating the local wave speed at a single site in the internal carotid artery

Abstract : Objectives: Local wave speed is a biomarker which provides an objective analysis of the cardiovascular function. The aim of this study was to determine the local wave speed in the internal carotid artery by a new non-invasive method that measures blood velocity waveform at only one site. Methods: For this purpose, the cepstral analysis was employed to determine the arrival time of the reflection wave and the wave speed in the carotid artery. To validate our model, we applied it experimentally in vivo on young and old healthy subjects. The blood velocity waveform was measured by using phase-contrast magnetic resonance for 22 subjects. Results: Our experimental results correlated with reference values reported in previous studies conducted on the internal arterial carotid usually adopting the invasive method. They also correlated with those obtained by using the foot-to-foot method (R-2 =0.72). The wave speed obtained by the method developed in this study and that of the foot-to-foot method increased with age (p<0.001). Conclusions: The method developed in this study can be applied in the other arteries and it can also be used with other techniques such as ultrasound imaging.