Volume elastic modulus of the brachial artery and coronary artery stenosis in patients with suspected stable coronary artery disease

This study aimed to examine the association between the non-invasive measurement of the brachial artery volume elastic modulus (VE), an index of arterial stiffness, and the presence of coronary artery stenosis in patients with suspected stable coronary artery disease (CAD). A total of 135 patients with suspected stable CAD (87 men, mean age, 64 ± 12 years) underwent oscillometric measurement of the brachial artery to obtain VE. Coronary angiography was thereafter carried out to diagnose CAD, defined as having ≥75 % stenosis in the epicardial coronary arteries. VE was significantly higher in patients with CAD (1.94 ± 0.34 mmHg/%) than in those without CAD (1.71 ± 0.35 mmHg/%, P < 0.001). In multiple logistic regression analysis, VE was an independent predictor for the presence of CAD (odds ratio 1.19 per 0.1 mmHg/% increase, 95 % CI 1.04–1.51) even after adjusting for multiple potential confounders including the Framingham risk score (FRS). The area under the curve of the receiver operating characteristic curve analysis for discriminating CAD increased significantly after the addition of VE to the FRS (from 0.75 to 0.81, P = 0.034). The category-free net reclassification improvement and the integrated discrimination improvement by adding VE to the FRS were 0.476 (95 % CI 0.146–0.806) and 0.086 (95 % CI 0.041–0.132), respectively. In conclusion, the brachial VE was significantly associated with the presence of coronary artery stenosis. The additional measurement of VE to the FRS improved the ability to identify patients with coronary artery stenosis among those with suspected stable CAD.