Interrelationship between non-invasive measurements of atherosclerosis: flow-mediated dilation of brachial artery, carotid intima-media thickness and pulse wave velocity.

Flow-mediated dilation (FMD) of the brachial artery, carotid intima-media thickness (IMT) and pulse wave velocity (PWV) have been shown to be good surrogate markers of clinical atherosclerosis. We determined the interrelation between these measurements, and examined whether their combination would be of clinical significance. One hundred and thirty-five consecutive subjects (79 women/56 men) were enrolled, including 110 patients with risk factors for atherosclerosis, and 33 patients with atherosclerotic disease such as coronary heart disease, stroke or arteriosclerosis obliterans. IMT and plaque formation of the carotid artery and FMD of the brachial artery were assessed using ultrasonography. Brachial-ankle PWV (baPWV) was measured using an automated device (form ABI/PWV, Colin). Age, FMD, IMT and PWV were significantly correlated with each other. Multivariate analysis revealed an independent correlation between the parameters except for FMD, and all four parameters were independently correlated with each other in subjects <70 years. Next, we classified the subjects by tertile according to the values of FMD, IMT and PWV. Each of the worst tertiles was associated with a higher prevalence of atherosclerotic disease and carotid plaques compared to the other tertiles. Moreover, subjects with the worst tertiles of all three measurements had a markedly higher prevalence of atherosclerotic disease and carotid plaques. These results suggest that FMD, IMT and PWV are related to each other, but the combination of these measurements will be of stronger clinical relevance.