Measurement of Flow-Mediated Vasodilation of the Brachial Artery A Comparison of Measurements in the Seated and Supine Positions

Abstract

Study ProtocolAll studies were performed in the morning, after overnight fasting, in a quiet, dark, air-conditioned room (conCirc J 2007; 71: 736 -740 (Received September 11, 2006; revised manuscript received February 13, 2007; accepted February 16, 2007 Background Measurement of flow-mediated vasodilation (FMD) is used to assess endothelial function in humans and according to the guidelines, subjects must remain supine during the study. However, measurement of FMD while seated would be more comfortable and convenient for patients, so the purpose of this study was to determine the effect of the patient's position on FMD results. Methods and ResultsHigh-resolution ultrasonography, a linear array transducer (13 MHz) and an arm -holding device were used to measure arterial diameter in response to reactive hyperemia (FMD, cuff inflated to 50 mmHg above systolic blood pressure for 5 min) and in response to sublingual nitroglycerine (NTG, 75 g) in 31 subjects, which included those with cardiovascular diseases. There was no significant difference between basal or peak hyperemic blood flow in the seated or supine position. Basal brachial artery diameter, FMD and vascular response to NTG were similar in both positions (basal diameter: 3.8±0.4 vs 3.9±0.4 mm, FMD: 7.3±4.3% vs 7.2±4.5%, NTG: 13.1±5.1% vs 12.8±5.6%). Conclusions The findings suggest that measurement of FMD in the seated position is as useful as measuring it in the supine position for assessing endothelial function. This flexibility of position is better for patients and physicians, and should lead to more widespread measurement of FMD. (Circ J 2007; 71: 736 -740)

Evaluation of the Effects of Acupuncture on Blood Flow in Humans with Ultrasound Color Doppler Imaging

“…We therefore used noninvasive color Doppler imaging (CDI) with ultrasound to evaluate blood flow. CDI is an examination technique that is widely used in the practice and research of Western medicine [13–21]. CDI can quantitatively measure intravascular blood flow in the extremities and in various organs in real-time.…”

Impact of Framingham Risk Score, Flow-Mediated Dilation, Pulse Wave Velocity, and Biomarkers for Cardiovascular Events in Stable Angina

“…Third, the measurement method for the FMD was rather old and the fixed time interval of measurement was somewhat long (one, two, and three minutes). In addition, we did not use the automated edge detection system that is frequently found in the literature at present (33). However, according to Corretti et al (13), nearly 70% of the NO is released in the first 60 sec after cuff release, and most maximal dilation occurs around one minute after cuff release.…”

The Pilot Study of Evaluating Fluctuation in the Blood Flow Volume of the Radial Artery, a Site for Traditional Pulse Diagnosis

“…Radial artery hemodynamics were assessed using ultrasonography (Prosound α10 ® ; Hitachi-Aloka Medical, Ltd., Tokyo, Japan). This system had a high-resolution linear array transducer (13 MHz, Prosound α10 ® ; Hitachi-Aloka Medical, Ltd., Tokyo, Japan) and computer-assisted analysis software (e-Tracking system ® ; Hitachi-Aloka Medical, Ltd., Tokyo, Japan) that could automatically detect a blood vessel edge and continuously measure the vessel diameter and Volume [20]. The right arm was fixed and the right radial artery was scanned longitudinally at 1–2 cm above the radial styloid process at a point where the vessel diameter and Doppler wave readings were stable.…”