Evaluation of brachial artery endothelial function in patients with idiopathic dilated cardiomyopathy by high-resolution ultrasonography

Objective To evaluate brachial artery endothelial function in patients with idiopathic dilated cardiomyopathy using reactive hyperemia-induced percent change in the brachial artery diameter measured by high-resolution ultrasonography. Methods Measurements of brachial artery diameter were performed by high-resolution ultrasonography during baseline,reactive hyperemia and sublingual nitroglycerin administration in twenty-one patients with idiopathic dilated cardiomyopathy and eighteen healthy subjects. Reactive hyperemia-induced and nitroglycerin-induced percent changes in brachial artery diameter were calculated. Results The percent change in the brachial artery diameter induced by reactive hyperemia in patients with idiopathic dilated cardiomyopathy [(4.2±4.7)%] was significantly less than that in healthy subjects [(11.4±3.7)%,P 0.001]. No significant difference could be found in percent change in the brachial artery diameter induced by sublingual nitroglycerin between the patients [(27.4±8.1)%] and the controls [(28.3±8.4)%, P =0.32]. Conclusion The decreased percent change in the brachial artery diameter induced by reactive hyperemia in patients with idiopathic dilated cardiomyopathy compared with the healthy subjects indicates that brachial endothelial function is impaired in patients with idiopathic dilated cardiomyopathy.