Integrative Human Physiology Laboratory, Manning College of Nursing & Health Sciences, University of Massachusetts Boston, Boston, MA, United States of America.
Ginásio Clube Português, Research & Development Department, GCP Lab, Lisboa, Portugal.
PLoS One. 2023 Jun 28;18(6):e0287759. doi: 10.1371/journal.pone.0287759. eCollection 2023.
Flow-mediated slowing (FMS) is a non-invasive measure of endothelial function measured through reactive hyperemia-induced changes in pulse wave velocity (PWV). FMS is suggested to mitigate known pitfalls of flow-mediated dilation (FMD) including suboptimal repeatability and high-operator dependency. However, the few single-rater studies that examined FMS repeatability have shown controversial results and used only regional measurements of PWV, which might not reflect local brachial artery stiffness responses to reactive hyperemia. We assessed the inter- and intra-rater repeatability of ultrasound-based changes in local PWV (FMS) and diameter (FMD). Twenty-four healthy male participants aged 23-75 yr, were examined on two separate days. Reactive hyperemia-induced changes in PWV were calculated using a tailored R-script. The inter- and intra-rater repeatability were tested with the intraclass correlation coefficient (ICC), coefficient of variation (CV), and the Bland-Altman plot estimates. The inter-rater repeatability of FMS (bias: -0.08%; ICC: 0.85; 95% CI: 0.65 to 0.93; CV: 11%) and FMD (bias: -0.02%; ICC: 0.98; 95% CI: 0.97 to 0.99; CV: 7%) showed overall good repeatability over different days. The intra-rater repeatability of FMD (1st rater: bias: 0.27%; ICC: 0.90; 95% CI: 0.78 to 0.96; CV: 14%; 2nd rater: bias: 0.60%; ICC: 0.85; 95% CI: 0.64 to 0.94; CV: 18%) was better than FMS (1st rater: bias: -1.03%; ICC: 0.76; 95% CI: 0.44 to 0.91; CV: 21%; 2nd rater: bias:-0.49%; ICC: 0.70; 95% CI: 0.34 to 0.80; CV: 23%) but not different between raters. Ultrasound-based local measurements of PWV deceleration reactive hyperemia were repeatable among the raters.
血流介导的舒张（FMD）是一种通过脉搏波速度（PWV）的反应性充血诱导变化来测量的内皮功能的非侵入性测量方法。FMD 被认为可以减轻血流介导的扩张（FMD）的已知缺陷，包括重复性不佳和高度依赖操作者。然而，少数对 FMS 重复性进行的单评分者研究显示出相互矛盾的结果，并且仅使用 PWV 的区域测量值，这可能无法反映反应性充血对肱动脉局部僵硬反应。我们评估了基于超声的局部 PWV（FMS）和直径（FMD）变化的评分者内和评分者间的重复性。24 名年龄在 23-75 岁的健康男性参与者在两天内进行了检查。使用定制的 R 脚本计算 PWV 反应性充血诱导的变化。使用组内相关系数（ICC）、变异系数（CV）和 Bland-Altman 图估计值测试评分者内和评分者间的重复性。FMS（偏差：-0.08%；ICC：0.85；95%CI：0.65 至 0.93；CV：11%）和 FMD（偏差：-0.02%；ICC：0.98；95%CI：0.97 至 0.99；CV：7%）的评分者间重复性在不同天之间显示出总体良好的重复性。FMD 的评分者内重复性（第一评分者：偏差：0.27%；ICC：0.90；95%CI：0.78 至 0.96；CV：14%；第二评分者：偏差：0.60%；ICC：0.85；95%CI：0.64 至 0.94；CV：18%）优于 FMS（第一评分者：偏差：-1.03%；ICC：0.76；95%CI：0.44 至 0.91；CV：21%；第二评分者：偏差：-0.49%；ICC：0.70；95%CI：0.34 至 0.80；CV：23%），但评分者之间无差异。反应性充血时基于超声的局部 PWV 减速的测量在评分者之间具有可重复性。
