Noninvasive ultrasonic measurement of regional and local pulse-wave velocity in mice.

Mouse models of human disease are increasingly used to study the nature of cardiovascular diseases such as atherosclerosis. The pulse wave velocity (PWV) provides an indirect measure of arterial stiffness and can be useful for characterizing disease progression. In this study, the PWV was measured noninvasively in the left common carotid artery of seven young mice using two image-guided approaches: a regional transit-time (TT) method and a local flow-area (QA) method. The QA approach measures the cross-sectional area and volume flow through the vessel using high frame-rate retrospective colour flow imaging. The QA method was found to correlate well with the TT method (r2=0.80, p<0.001). The mean difference between methods was 0.05+/-0.21 m/s. This study demonstrates the feasibility of measuring both regional and local PWV in mice using image-based high-frequency ultrasound methodologies.