Division of Clinical Pharmacology, Department of Medicine, Vanderbilt Autonomic Dysfunction Center, Vanderbilt University Medical Center, 560A RRB, 2222 Pierce Ave,, Nashville, TN, 37232, USA.
Vanderbilt University School of Medicine, Nashville, TN, USA.
Clin Auton Res. 2021 Aug;31(4):563-571. doi: 10.1007/s10286-021-00772-y. Epub 2021 Mar 10.
Postural tachycardia syndrome (POTS), a syndrome characterized by orthostatic symptoms and a heart rate increase of at least 30 beats per minute in the absence of hypotension upon standing, is often accompanied by increased sympathetic activity and low blood volume. A common non-pharmacologic recommendation for patients with POTS is a high-sodium (HS) diet with the goal of bolstering circulating blood volume. The objective of this study is to assess the effects of 6 days of a HS diet on endothelial function in POTS.
A total of 14 patients with POTS and 13 age-matched healthy controls, all females, were studied following 6 days on a low-sodium (LS) diet (10 mEq/day) and 6 days on a HS diet (300 mEq/day) in a crossover design. We measured endothelial function following reactive hyperemia in the brachial artery using flow-mediated dilation (FMD), leg blood flow (LBF) using strain gauge plethysmography in the calf, and reactive hyperemic index (RHI) in the microcirculation of the hand using pulsatile arterial tonometry.
On the LS diet, FMD% did not differ between patients with POTS and the healthy controls although peak brachial artery diameter was lower for the patient group. RHI was higher for the patient group than for the controls, but there were no differences in post-ischemic LBF increase. On the HS diet, there were no between-group differences in FMD%, LBF increase, or RHI.
In summary, a HS diet for 6 days did not induce endothelial dysfunction. This non-pharmacologic treatment used for patients with POTS does not negatively affect endothelial function when used for a sub-acute duration.
ClinicalTrials.gov NCT01550315; March 9, 2012.
体位性心动过速综合征（POTS）是一种以直立时出现体位症状和心率至少增加 30 次/分为特征的综合征，且不存在低血压。通常伴有交感神经活性增加和血容量低。对于 POTS 患者的一种常见非药物推荐是高钠（HS）饮食，目的是增加循环血容量。本研究的目的是评估 6 天 HS 饮食对 POTS 患者内皮功能的影响。
共纳入 14 名 POTS 患者和 13 名年龄匹配的健康对照者（均为女性），在交叉设计中，他们先进行 6 天低钠（LS）饮食（10mEq/天），再进行 6 天 HS 饮食（300mEq/天）。我们通过肱动脉反应性充血后使用血流介导的扩张（FMD）来测量内皮功能，通过小腿应变计体积描记法测量小腿血流（LBF），通过脉冲动脉张力测定法测量手部微循环的反应性充血指数（RHI）。
在 LS 饮食时，尽管患者组的肱动脉峰值直径较低，但 POTS 患者和健康对照组之间的 FMD% 没有差异。与对照组相比，患者组的 RHI 较高，但缺血后 LBF 增加没有差异。在 HS 饮食时，FMD%、LBF 增加或 RHI 没有组间差异。
总之，6 天 HS 饮食不会引起内皮功能障碍。这种用于治疗 POTS 患者的非药物治疗在亚急性使用时不会对内皮功能产生负面影响。
ClinicalTrials.gov NCT01550315；2012 年 3 月 9 日。
