BACKGROUND Patients with postural tachycardia syndrome (POTS) experience considerable disability, but in most, the pathophysiology remains obscure. Plasma volume disturbances have been implicated in some patients. We prospectively tested the hypothesis that patients with POTS are hypovolemic compared with healthy controls and explored the role of plasma renin activity and aldosterone in the reg...

Patients with POTS (postural tachycardia syndrome) have excessive orthostatic tachycardia (>30 beats/min) when standing from a supine position. HR (heart rate) and BP (blood pressure) are known to exhibit diurnal variability, but the role of diurnal variability in orthostatic changes of HR and BP is not known. In the present study, we tested the hypothesis that there is diurnal variation of ort...

Background The pathogenesis of postural tachycardia syndrome (POTS) remains unclear. This study aimed to explore the changes and significance of sulfur dioxide (SO2) in patients with POTS. Methods The study included 31 children with POTS and 27 healthy children from Peking University First Hospital between December 2013 and October 2015. A detailed medical history, physical examination result...

Postural Tachycardia Syndrome (POTS) Print ISSN: 0009-7322. Online ISSN: 1524-4539 Copyright © 2013 American Heart Association, Inc. All rights reserved. is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231 Circulation doi: 10.1161/CIRCULATIONAHA.112.144501 2013;127:2336-2342 Circulation. http://circ.ahajournals.org/content/127/23/2336 World Wide Web at: The ...

Low-flow postural tachycardia syndrome (POTS) is associated with increased plasma angiotensin II (ANG II) and reduced neuronal nitric oxide (NO), which decreases NO-dependent vasodilation. We tested whether the ANG II type 1 receptor (AT(1)R) antagonist losartan would improve NO-dependent vasodilation in POTS patients. Furthermore, if the action of ANG II is dependent on NO, then the NO synthas...

Postural tachycardia syndrome (POTS) is a heterogeneous disorder characterized by an excessive rise in heart rate and symptoms consistent with cerebral hypoperfusion in the upright position. NO produced by endothelial NO synthase is a significant factor in the regulation of blood flow. Genetic polymorphisms in the promoter region (T-786C) and exon 7 (E298D) of the NO synthase isoform 3 gene aff...

Postural tachycardia syndrome (POTS), characterized by orthostatic tachycardia in the absence of orthostatic hypotension, has been the focus of increasing clinical interest over the last 15 years 1. Patients with POTS complain of symptoms of tachycardia, exercise intolerance, lightheadedness, extreme fatigue, headache and mental clouding. Patients with POTS demonstrate a heart rate increase of ...

Orthostatic intolerance can be defi ned as inability to tolerate upright posture relieved by recumbence. Postural orthostatic tachycardia syndrome (POTS) is a form of orthostatic intolerance defi ned as sustained increase in heart rate of ≥30 bpm or increase of heart rate to ≥120 bpm within 10 min of standing or head-up tilt associated with symptoms of orthostatic intolerance and absence of ort...

References 1. Lo YMD, Hjelm NM, Fidler C, Sargent IL, Murphy MF, Chamberlain PF, et al. Prenatal diagnosis of fetal RhD status by molecular analysis of maternal plasma. N Engl J Med 1998;339:1734–8. 2. Chiu RWK, Lau TK, Leung TN, Chow KCK, Chui DHK, Lo YMD. Prenatal exclusion of thalassaemia major by examination of maternal plasma. Lancet 2002;360:998–1000. 3. Zhong XY, Laivuori H, Livingston J...

BACKGROUND A subgroup of patients suffering from Lyme disease (LD) may initially respond to antibiotics only to later develop a syndrome of fatigue, joint pain and cognitive dysfunction referred to as 'post treatment LD syndrome'. We report on a series of patients who developed autonomic dysfunction in the form of postural orthostatic tachycardia syndrome (POTS). METHODS All of the patients i...