Atherosclerosis progression affects the relationship between endothelial function and aortic stiffness

Aortic stiffening is the most important determinant of elevated systolic blood pressure which in turn is the main contributor to the burden of disease attributable to hypertension. Endothelial function may affect arterial stiffening as has been shown for carotid-aorto-femoral segments in healthy humans or subjects with cardiovascular risk factors. We investigated whether this association is present selectively for aorta and whether it extends to patients with advanced atherosclerosis. Direct measurements of aortic pulse wave velocity (aPWV) to assess aortic stiffness and brachial artery flow-mediated dilatation (bFMD) tests to assess endothelial function were performed in 111 consecutive patients suspected of coronary artery disease. Progression of atherosclerosis was determined on the basis of the presence or absence of significant coronary artery stenosis, CAS (>or=50%) in angiography. bFMD was lower (P<0.001) and aPWV was higher (P<0.001) in a group of 72 patients with advanced atherosclerosis when compared with a group of 39 patients without significant CAS. bFMD was inversely associated with aPWV but only in patients without advanced atherosclerosis (r=-0.37, P=0.02), even after adjustment of confounding factors in a multivariate analysis model (R(2)=0.37, P<0.001). We concluded that endothelial function may influence aortic stiffness which is limited however by the progression of atherosclerosis.