OBJECTIVETo investigate the change in endothelium-dependent vasodilation and arterial elasticity and the association between them in patients with coronary artery disease (CAD).

METHODSThirty patients with CAD and thirty control subjects were recruited for this study. Flow-mediated dilation (FMD) in the brachial artery was evaluated by ultrasound Doppler flow method. They also underwent a non-invasive assessment of C(1) large artery and C(2) small artery indices by using pulse wave analysis.

RESULTSFMD was significantly reduced in CAD group compared with that in control group [(5.17 +/- 2.13)% vs (11.1 +/- 4.36)%, P < 0.05], C(1) large artery elasticity index was similar between the two groups [(11.59 +/- 4.56) ml/mm Hg x 10 vs (12.11 +/- 3.82) ml/mm Hg x 10, P > 0.05]. However, C(2) small artery elasticity index was significantly reduced in CAD group compared with that in control group [(4.20 +/- 1.80) ml/mm Hg x 100 vs (6.26 +/- 2.36) ml/mm Hg x 100, P < 0.05]. There was a positive association between reduced C(2) small artery elasticity index and impaired FMD (r = 0.53, P < 0.05).

CONCLUSIONSThere were impaired endothelium-dependent vasodilation and reduced C(2) small artery elasticity index in the patients with CAD, which were closely correlated with each other. The present study suggested that the measurement of C(2) small artery elasticity might be used as a novel index for the determination of endothelial function.