• Public health

To the Editor There is increasing evidence that the mechanical properties of the aorta, and arterioventricular coupling, are of great clinical importance in cardiovascular diseases. Therefore, we read the paper by Vitarelli et al with great interest.1

Given the recent evolution of ultrasound equipment and processing tools, the suggestion of assessing the aorta using velocity and deformation information is interesting, but the way it is used by the authors is confusing.

They measure the velocity of one point on the aortic wall and suggest that this is related to stiffness of the wall. However, the velocity describes the motion of the wall within the thorax rather than the extension of the wall due to the internal pressure (the intrinsic deformation, determined by the pressure within and the stiffness of the vessel). As opposed to the carotid artery, which is not showing substantial overall motion, to measure aortic distension, the difference in motion of the proximal and distal walls has to be assessed, as described, for example, by Long A, et al. …