Leveling of arterial wall stiffness between aortic arch and left carotid artery due to aging is associated with reduced volume flow towards the brain: pulse wave velocity evaluation with high-field velocity-encoded MRI

Background A discrete transition of wall stiffness at the interface of a compliant aorta and stiffer carotid arteries creates a reflection site for the aortic pulse wave and consequently limits excessive pulsatile energy transmission towards the brain. Arterial wall stiffness can be expressed by the pulse wave velocity (PWV) and dualslice one-directional through-plane velocity-encoded (VE) MRI is well-validated for accurate PWV-assessment. The hypothesis is that with aging, leveling of PWV across the aortic arch and carotid artery will occur with negative effect on the flow towards the brain. The purpose of this study was to evaluate PWV and volume flow in aorta and carotid artery in younger and older volunteers using 3T VE MRI.