Aortic Aging in XXXX : Structural, Hemodynamic, and Mortality Implications.

@entity1 @entity730 @entity2333 @entity122 @entity454
UNASSIGNED: Aging incurs aortic stiffening and dilation, but these changes are less pronounced in peripheral arteries, resulting in stiffness and geometry gradients influencing progression of the forward and reflected pressure waves. Because premature arterial aging is observed in @entity454 , we determined the respective roles of stiffness and aortic geometry gradients in 73 controls and 156 @entity1 on hemodialysis. We measured aortic pulse wave velocity ( @entity122 ) and brachial @entity122 to evaluate the stiffness gradient [(brachial @entity122 /aortic @entity122 )(0.5)] and ascending aortic and aortic bifurcation diameters to assess aortic taper (ascending aortic diameter/aortic bifurcation diameter). The global reflection coefficient was estimated from characteristic impedance and vascular resistance. Cox proportional hazard models were used to determine mortality risk. The age-associated increase in aortic @entity122 was higher in @entity1 (P<0.001). In controls, aortic ascending and bifurcation diameters increased with age, with an unchanged aortic taper. In @entity1 on hemodialysis, age did not associate with increased ascending aortic diameter but did associate with increased aortic bifurcation diameter and decreased aortic taper, both of which also associated with @entity730 and smaller global reflection coefficient (P<0.001). In @entity1 , multivariate models revealed all-cause and cardiovascular mortality associated with age, aortic @entity122 , and aortic bifurcation diameter with high specificity and sensitivity. Using stiffness gradient, aortic taper, or global reflection coefficient in the model produced similar results. Thus, whereas @entity2333 is a known independent predictor of mortality, these results indicate the importance of also evaluating the aortic geometry in @entity1 on hemodialysis.
