From the Vanderbilt University School of Medicine (A.H.C.), Vanderbilt University Medical Center, Nashville, TN.
Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine (A.W., J.C., V.N., E.C.S., E.M.G., S.P., L.E.O., B.K.B., I.B., A.G.), Vanderbilt University Medical Center, Nashville, TN.
Hypertension. 2021 Mar 3;77(3):1001-1009. doi: 10.1161/HYPERTENSIONAHA.120.16238. Epub 2021 Jan 25.
The purpose of this study is to evaluate endothelial function in postural tachycardia syndrome (PoTS), a poorly understood chronic condition characterized by a state of consistent orthostatic tachycardia (delta heart rate ≥30 beats per minute) upon standing without orthostatic hypotension. Nineteen patients with PoTS and 9 healthy controls were studied after 3 days of a fixed, caffeine-free, normal sodium (150 milliequivalents/day) diet. All participants underwent autonomic function testing, including sinus arrhythmia, valsalva maneuver, hyperventilation, cold pressor, handgrip, and a standing test with catecholamine measurements, followed by endothelial function testing. We analyzed 3 measures of endothelial function: percent brachial flow-mediated dilation, digital pulsatile arterial tonometry, and postischemic percent leg blood flow. Flow-mediated dilation was significantly lower in patients with PoTS (6.23±3.54% for PoTS) than in healthy controls (10.6±4.37% for controls versus, =0.014). PoTS and controls had similar digital pulsatile arterial tonometry (1.93±0.40 arbitrary units for controls versus 2.13±0.63 arbitrary units for PoTS). PoTS had similar but suggestive percent leg blood flow to controls (313±158% for PoTS versus 468±236% for controls, =0.098). Patients with PoTS have significantly reduced flow-mediated dilation compared with healthy controls, suggesting that PoTS is characterized by endothelial dysfunction in conduit arteries. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01308099.
这项研究的目的是评估体位性心动过速综合征（PoTS）患者的血管内皮功能。PoTS 是一种慢性疾病，其特征是在没有体位性低血压的情况下站立时持续出现直立性心动过速（心率差值≥30 次/分钟）。19 名 PoTS 患者和 9 名健康对照者在接受 3 天固定、无咖啡因、正常钠（150 毫当量/天）饮食后接受研究。所有参与者均接受自主神经功能测试，包括窦性心律失常、瓦尔萨尔瓦动作、过度通气、冷加压、握力和去甲肾上腺素测量的站立试验，随后进行内皮功能测试。我们分析了 3 种内皮功能测量指标：肱动脉血流介导的扩张百分比、指端脉搏动脉张力测定和缺血后腿部血流百分比。PoTS 患者的血流介导的扩张明显低于健康对照组（PoTS 患者为 6.23±3.54%，健康对照组为 10.6±4.37%，=0.014）。PoTS 和对照组的指端脉搏动脉张力测定相似（对照组为 1.93±0.40 个任意单位，PoTS 组为 2.13±0.63 个任意单位）。PoTS 患者的腿部血流百分比与对照组相似，但具有提示性（PoTS 患者为 313±158%，对照组为 468±236%，=0.098）。与健康对照组相比，PoTS 患者的血流介导的扩张明显降低，这表明 PoTS 患者的大血管内皮功能障碍。注册：网址：https://www.clinicaltrials.gov。唯一标识符：NCT01308099。
