FMD measurement protocol
artery transducer
REACTIVE HYPEREMIA
After overnight fasting, all experiments were conducted in the morning. All of the patients were kept in the supine position in a calm, dark, air-conditioned room with a constant temperature of 22 ℃–25 ℃ throughout the study. A 23-gauge polyethylene catheter was placed in the left deep antecubital vein to collect blood samples. Endothelium-dependent FMD was assessed based on the vascular response to reactive hyperemia in the brachial artery. Observers were blinded to the examinations.FMD was measured using the same ultrasound device designed for FMD measurements and the same protocol in all institutions. A high-resolution linear artery transducer was coupled to computer-assisted analysis software (UNEXEF18G, UNEX Co, Nagoya, Japan), which uses an automated edge detection system for the measurement of brachial artery diameter [