 Endothelial-dependent vasodilation was assessed by ischemia-induced reactive hyperemia. Briefly, after 12-hour overnight fasting patients were examined at 8 a.m. in a quiet room at 22oC by using a ultrasound equipment Vivid i GE Healthcare, Wauwatosa, WI, USA with a high-resolution up to 13 MHz vascular probe 12l-RS, GE Healthcare, Wauwatosa, WI, USA in B-mode. The cardiac cycles were monitored simultaneously by electrocardiography coupled to the equipment. Flow-mediated dilation FMD was assessed after 5-minutes inflation of a cuff placed below the transducer, 50 mm Hg above the systolic blood pressure. Two-dimensional images of the brachial artery were obtained during 5 minutes from the longitudinal axis approximately 5-10 cm above the antecubital fossa. The maximum expansion of the diameter of the brachial artery was measured in triplicate at the peak of the T wave of the cardiac cycle before the interruption of the flow and post deflation. 