Department of Kinesiology and Health Education, University of Texas, Austin, TX 78712, USA.
J Hum Hypertens. 2012 Jan;26(1):35-40. doi: 10.1038/jhh.2010.128. Epub 2011 Jan 20.
Flow-mediated dilatation (FMD) is widely used as an index of nitric oxide-mediated vasodilator function, yet its methodology has not been well established. Previous research indicates that a rapid inflation of a blood pressure cuff evokes systemic vasoconstriction, as it was observed even on non-occluded contralateral arm. This would potentially contribute to the variability of FMD readings and complicate the emerging evidence that non-occluded contralateral arm fingertip temperature responses during the FMD procedure may be an indicator of the presence of coronary artery disease. To test the hypotheses that rapid inflation of a blood pressure cuff could reduce FMD values and influence contralateral vasodilatory states, 33 apparently healthy adults (18 males and 15 females, 29±6 years) were studied in two randomized FMD trials. The blood flow-occluding cuff was inflated rapidly (<1 s) in one trial or slowly over 10 s in the other trial. Arterial diameter, fingertip temperature and infrared thermography were obtained throughout each session. FMD values were not different between the rapid and slow cuff inflation trials (5.9±0.6 vs 5.9±0.4%). There were no differences in reactive hyperaemia (6.4±1.6 vs 6.2±1.7 AU), shear stress (80±20 vs 77±17 dyn cm(-2)) and fingertip temperature rebound (TR; 1.8±1.2 vs 1.9±1.0 °C) between the rapid and slow inflation. Changes in finger temperature on the contralateral (non-occluded) arm were positively associated with those on the occluded arm (r=0.26 to 0.61, P<0.05). We concluded that rates of inflating a blood pressure cuff do not affect FMD and TR response, and that neurovascular-induced vasodilatation of the contralateral arm was not observed regardless of cuff inflation rates.
血流介导的扩张（FMD）被广泛用作一氧化氮介导的血管舒张功能的指标，但它的方法尚未得到很好的确立。先前的研究表明，血压袖带的快速充气会引起全身血管收缩，因为即使在未闭塞的对侧手臂上也观察到了这种情况。这可能会导致 FMD 读数的变异性，并使非闭塞对侧手臂指尖温度反应在 FMD 过程中可能是冠心病存在的指标这一新兴证据变得复杂。为了检验快速充气血压袖带可能降低 FMD 值并影响对侧血管舒张状态的假设，我们在两项随机 FMD 试验中研究了 33 名看似健康的成年人（18 名男性和 15 名女性，29±6 岁）。在一项试验中，血流闭塞袖带快速（<1 秒）充气，在另一项试验中缓慢充气 10 秒。在每个阶段都获得了动脉直径、指尖温度和红外热成像。快速和缓慢充气袖带充气试验之间的 FMD 值没有差异（5.9±0.6 对 5.9±0.4%）。反应性充血（6.4±1.6 对 6.2±1.7 AU）、剪切应力（80±20 对 77±17 dyn cm(-2)) 和指尖温度反弹（TR；1.8±1.2 对 1.9±1.0°C）在快速和缓慢充气之间没有差异。对侧（未闭塞）手臂上的手指温度变化与闭塞手臂上的温度变化呈正相关（r=0.26 至 0.61，P<0.05）。我们得出的结论是，充气血压袖带的速度不会影响 FMD 和 TR 反应，并且无论充气速度如何，都没有观察到对侧手臂的神经血管诱导性血管舒张。
