Background: The diagnostic and prognostic importance of brachial artery flow-mediated dilation (BFMD) for cardiovascular disease (CVD) is not certain and associations between BFMD and recognized measures of atherosclerosis have not been well established.
Methods: We investigated cross-sectional and longitudinal correlations between repeated measures of BFMD and quantitative coronary artery angiographic (QCA) measurements of average percent diameter stenosis, number of lesions and minimum luminal diameter (MLD), and ultrasonographic measurement of carotid artery intima-media thickness (CIMT) in an ethnically diverse cohort of postmenopausal women (n=132) with coronary artery disease (CAD). Subjects were participants in a 3-year randomized, placebo-controlled clinical trial, testing the efficacy of hormone therapy on atherosclerosis progression. Associations between BFMD and QCA measures, and between BFMD and CIMT were examined using measurements from the same study visit.
Results: BFMD was significantly inversely correlated with coronary artery stenosis at baseline (beta=-1.21% [S.E.(beta)=0.38], p=0.002). BFMD levels significantly predicted rate of change in CIMT over the trial period (beta=-0.76 microm/year [S.E.(beta)=0.29], p=0.008).
Conclusions: Physiological and anatomical measures of atherosclerosis are correlated among postmenopausal women with CAD, which provides some validation of BFMD as a measure of atherosclerosis in high-risk populations.