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Luchian ML, Higny J, Benoit M, Robaye B, Berners Y, Henry JP, Colle B, Xhaët O, Blommaert D, Droogmans S, Motoc AI, Cosyns B, Gabriel L, Guedes A, Demeure F. Unmasking Pandemic Echoes: An In-Depth Review of Long COVID's Unabated Cardiovascular Consequences beyond 2020. Diagnostics (Basel) 2023; 13:3368. [PMID: 37958264 PMCID: PMC10647305 DOI: 10.3390/diagnostics13213368] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/23/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
At the beginning of 2020, coronavirus disease 2019 (COVID-19) emerged as a new pandemic, leading to a worldwide health crisis and overwhelming healthcare systems due to high numbers of hospital admissions, insufficient resources, and a lack of standardized therapeutic protocols. Multiple genetic variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been detected since its first public declaration in 2020, some of them being considered variants of concern (VOCs) corresponding to several pandemic waves. Nevertheless, a growing number of COVID-19 patients are continuously discharged from hospitals, remaining symptomatic even months after their first episode of COVID-19 infection. Long COVID-19 or 'post-acute COVID-19 syndrome' emerged as the new pandemic, being characterized by a high variability of clinical manifestations ranging from cardiorespiratory and neurological symptoms such as chest pain, exertional dyspnoea or cognitive disturbance to psychological disturbances, e.g., depression, anxiety or sleep disturbance with a crucial impact on patients' quality of life. Moreover, Long COVID is viewed as a new cardiovascular risk factor capable of modifying the trajectory of current and future cardiovascular diseases, altering the patients' prognosis. Therefore, in this review we address the current definitions of Long COVID and its pathophysiology, with a focus on cardiovascular manifestations. Furthermore, we aim to review the mechanisms of acute and chronic cardiac injury and the variety of cardiovascular sequelae observed in recovered COVID-19 patients, in addition to the potential role of Long COVID clinics in the medical management of this new condition. We will further address the role of future research for a better understanding of the actual impact of Long COVID and future therapeutic directions.
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Affiliation(s)
- Maria-Luiza Luchian
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Julien Higny
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Martin Benoit
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Benoit Robaye
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Yannick Berners
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Jean-Philippe Henry
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Benjamin Colle
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Olivier Xhaët
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Dominique Blommaert
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Steven Droogmans
- Department of Cardiology, Centrum voor Hart-en Vaatziekten, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium
| | - Andreea Iulia Motoc
- Department of Cardiology, Centrum voor Hart-en Vaatziekten, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium
| | - Bernard Cosyns
- Department of Cardiology, Centrum voor Hart-en Vaatziekten, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (VUB), Laarbeeklaan 101, 1090 Brussels, Belgium
| | - Laurence Gabriel
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Antoine Guedes
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
| | - Fabian Demeure
- Department of Cardiology, Université Catholique de Louvain, CHU UCL Namur Site Godinne, Av. Dr. G. Thérasse, 1, 5530 Yvoir, Belgium (A.G.); (F.D.)
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Laurin JKH, Oyewunmi OA, Garland EM, Gamboa A, Nwazue VC, Paranjape SY, Black BK, Okamoto LE, Shibao CA, Biaggioni I, Robertson D, Diedrich A, Dupont WD, Sheldon RS, Raj SR. Adrenal gland response to adrenocorticotropic hormone is intact in patients with postural orthostatic tachycardia syndrome. Auton Neurosci 2023; 248:103105. [PMID: 37393658 DOI: 10.1016/j.autneu.2023.103105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 05/18/2023] [Accepted: 06/20/2023] [Indexed: 07/04/2023]
Abstract
BACKGROUND Many patients with postural orthostatic tachycardia syndrome (POTS) are hypovolemic with plasma volume deficits of 10-30 %. Some also have low levels of aldosterone and diminished aldosterone-renin ratios despite elevations in angiotensin II, pointing to potential adrenal dysfunction. To assess adrenal gland responsiveness in POTS, we measured circulating levels of aldosterone and cortisol following adrenocorticotropin hormone (ACTH) stimulation. METHODS While on a low Na+ diet (∼10 mEq/day), 8 female patients with POTS and 5 female healthy controls (HC) received a low dose (1 μg) ACTH bolus following a baseline blood sample. After 60 min, a high dose (249 μg) infusion of ACTH was administered to ensure maximal adrenal response. Venous aldosterone and cortisol levels were sampled every 30 min for 2 h. RESULTS Aldosterone increased in both groups in response to ACTH but was not different between POTS vs. HC at 60 min (53.5 ng/dL [37.8-61.8 ng/dL] vs. 46.1 ng/dL [36.7-84.9 ng/dL]; P = 1.000) or maximally (56.4 ng/dL [49.2-67.1 ng/dL] vs. 49.5 ng/dL [39.1-82.8 ng/dL]; P = 0.524). Cortisol increased in both groups in response to ACTH but was not different in patients with POTS vs. HC at 60 min (39.9 μg/dL [36.1-47.7 μg/dL] vs. 39.3 μg/dL [35.4-46.6 μg/dL]; P = 0.724) or maximally (39.9 μg/dL [33.9-45.4 μg/dL] vs. 42.0 μg/dL [37.6-49.7 μg/dL]; P = 0.354). CONCLUSIONS ACTH appropriately increased the aldosterone and cortisol levels in patients with POTS. These findings suggest that the response of the adrenal cortex to hormonal stimulation is intact in patients with POTS.
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Affiliation(s)
- Jill K H Laurin
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Oyebimbola A Oyewunmi
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Emily M Garland
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Alfredo Gamboa
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Victor C Nwazue
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sachin Y Paranjape
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Bonnie K Black
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Luis E Okamoto
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Cyndya A Shibao
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Italo Biaggioni
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - David Robertson
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - André Diedrich
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, School of Engineering, Vanderbilt University, Nashville, TN, USA
| | - William D Dupont
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Robert S Sheldon
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Satish R Raj
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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Spahic JM, Mattisson IY, Hamrefors V, Johansson M, Ricci F, Nilsson J, Melander O, Sutton R, Fedorowski A. Evidence for Impaired Renin Activity in Postural Orthostatic Tachycardia Syndrome. J Clin Med 2023; 12:4660. [PMID: 37510775 PMCID: PMC10380257 DOI: 10.3390/jcm12144660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/09/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
BACKGROUND Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous condition predominantly affecting autonomic control of the cardiovascular system. Its extensive symptom diversity implies multi-organ involvement that interacts in ways still requiring full exploration. Current understanding of POTS pathophysiology suggests alterations in the renin-angiotensin-aldosterone system as a possible contributing factor. Therefore, we investigated the relationship between the activity of the renin-angiotensin-aldosterone system and hemodynamic parameters in a cohort of POTS patients and controls recruited at a tertiary referral center. METHODS The case-control study included 46 patients with POTS (27 ± 9 years), and 48 healthy controls (30 ± 9 years) without orthostatic intolerance. Plasma renin activity, expressed as angiotensin I generation, and plasma aldosterone were measured by enzyme-linked immunosorbent assay and were correlated with hemodynamic parameters obtained during active standing tests. RESULTS Renin activity was significantly downregulated in POTS patients compared to healthy individuals (median, 3406 ng/mL vs. 9949 ng/mL, p < 0.001), whereas aldosterone concentration did not differ between POTS and healthy controls (median, 218 pmol/L vs. 218 pmol/L, p = 0.26). A significant inverse correlation between renin activity and supine and orthostatic blood pressure levels was observed in healthy individuals (p < 0.05 for all), but not in POTS patients. CONCLUSIONS Renin activity, but not aldosterone concentration, is downregulated in patients with POTS. Moreover, renin activity in POTS is dissociated from supine and standing blood pressure levels in contrast to healthy individuals. These findings suggest impaired renin function in POTS, which may direct future therapeutic approaches.
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Affiliation(s)
| | - Ingrid Yao Mattisson
- Department of Internal Medicine, Skåne University Hospital, 214 28 Malmö, Sweden
| | - Viktor Hamrefors
- Department of Cardiology, Skåne University Hospital, 214 28 Malmö, Sweden
| | | | - Fabrizio Ricci
- Department of Clinical Sciences, Lund University, 214 28 Malmö, Sweden
- Department of Neuroscience, Imaging and Clinical Sciences, "G.d'Annunzio" University of Chieti-Pescara, Via dei Vestini 33, 66100 Chieti, Italy
- Fondazione Villa Serena per la Ricerca, 65013 Città Sant'Angelo, Italy
| | - Jan Nilsson
- Department of Clinical Sciences, Lund University, 214 28 Malmö, Sweden
| | - Olle Melander
- Department of Clinical Sciences, Lund University, 214 28 Malmö, Sweden
| | - Richard Sutton
- National Heart and Lung Institute, Imperial College, Hammersmith Hospital Campus Du Cane Road, London W12 0HS, UK
| | - Artur Fedorowski
- Department of Clinical Sciences, Lund University, 214 28 Malmö, Sweden
- Department of Cardiology, Karolinska University Hospital, Department of Medicine, Karolinska Institute, 171 77 Stockholm, Sweden
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Minhas R, Bharadwaj AS. COVID-19-Induced Postural Orthostatic Tachycardia Syndrome and Dysautonomia. Cureus 2023; 15:e40235. [PMID: 37435242 PMCID: PMC10332885 DOI: 10.7759/cureus.40235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2023] [Indexed: 07/13/2023] Open
Abstract
Postural orthostatic tachycardia syndrome (POTS) is a disorder characterized by orthostatic intolerance and, by definition, includes clinical symptoms of lightheadedness, palpitations, and tremulousness among others. It is considered a relatively rare condition that affects approximately 0.2% of the general population, and it is estimated that between 500,000 to 1,000,000 individuals in the United States have the condition and recently has been linked to post-infectious (viral) etiologies. We present a case of a 53-year-old woman who was diagnosed with POTS following extensive autoimmune workup, who was also status post-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The post-coronavirus disease 2019 (COVID-19) cardiovascular autonomic dysfunction can affect global circulatory control, which describes increased heart rate even at resting states, and local circulatory disorders, such as coronary microvascular disease leading to vasospasm, as described by the patient's chest pain, and venous retention leading to pooling and reduced venous return after standing. Along with tachycardia with orthostatic intolerance, other symptoms can also accompany the syndrome. In the majority of patients, intravascular volume is reduced, leading to decreased venous return to the heart and causing reflex tachycardia and orthostatic intolerance. Management varies from lifestyle modifications to pharmacologic therapy, to which patients generally show a good response. POTS should be a differential on the cards, especially in patients post-COVID-19 infection, as these symptoms can be misdiagnosed as having psychological etiologies.
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Affiliation(s)
- Resnah Minhas
- Medicine, American University of Antigua, St. Johns, ATG
| | - Adithya Sateesh Bharadwaj
- Medicine, University of Maryland Midtown Campus, Baltimore, USA
- Medicine, American University of Antigua, St. Johns, ATG
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Zha K, Brook J, McLaughlin A, Blitshteyn S. Gluten-free diet in postural orthostatic tachycardia syndrome (POTS). Chronic Illn 2023; 19:409-417. [PMID: 35098721 DOI: 10.1177/17423953221076984] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVES Postural orthostatic tachycardia syndrome (POTS) is a chronic disorder of the autonomic nervous system that is associated with orthostatic intolerance (OI) and gastrointestinal (GI) symptoms. We aimed to determine if a gluten-free diet (GFD) may be an effective treatment in patients with POTS. METHODS Patients with confirmed POTS and without celiac disease who followed GFD for 4 weeks retrospectively completed pre- and post- GFD COMPASS-31 questionnaires. Paired-samples t-tests were conducted to compare COMPASS-31 scores before and after adopting GFD. RESULTS All 20 patients (all females, age 16-62 years (mean age 33)), had POTS symptoms for 1-30 years (mean 10.8, SD = 10.23 years). Eleven patients had co-morbid mast cell activation syndrome, and 8 had hypermobile Ehlers-Danlos syndrome. Pre-GFD COMPASS-31 scores (mean 57.8) were significantly higher than post-GFD scores (mean 38.2, t(19) = -8.92, p < 0.00001), with the largest improvement noted in the OI (p < 0.00001), vasomotor, (p = 0.0034), and GI (p = 0.0004) domains and with a mean reduction in total COMPASS-31 score by 33.9% after implementing GFD. All patients reported improved symptoms on GFD with mean self-assessed improvement of 50.5% (range 10-99%). DISCUSSION GFD may be effective in reducing the symptom burden in patients with POTS, particularly in the OI, vasomotor, and GI symptom domains. Large prospective studies are necessary to confirm whether GFD is an effective long-term treatment option for patients.
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Affiliation(s)
- Kate Zha
- Department of Neurology, 12291University at Buffalo Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Jill Brook
- Dysautonomia Clinic, Williamsville, NY, USA
| | - Abigail McLaughlin
- Department of Neurology, 12291University at Buffalo Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY, USA
| | - Svetlana Blitshteyn
- Department of Neurology, 12291University at Buffalo Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY, USA.,Dysautonomia Clinic, Williamsville, NY, USA
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COVID-19 Induced Postural Orthostatic Tachycardia Syndrome (POTS): A Review. Cureus 2023; 15:e36955. [PMID: 37009342 PMCID: PMC10065129 DOI: 10.7759/cureus.36955] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2023] [Indexed: 04/03/2023] Open
Abstract
POTS (Postural Orthostatic Tachycardia Syndrome) is a multisystem disorder characterized by the abnormal autonomic response to an upright posture, causing orthostatic intolerance and excessive tachycardia without hypotension. Recent reports suggest that a significant percentage of COVID-19 survivors develop POTS within 6 to 8 months of infection. Prominent symptoms of POTS include fatigue, orthostatic intolerance, tachycardia, and cognitive impairment. The exact mechanisms of post-COVID-19 POTS are unclear. Still, different hypotheses have been given, including autoantibody production against autonomic nerve fibers, direct toxic effects of SARS-CoV-2, or sympathetic nervous system stimulation secondary to infection. Physicians should have a high suspicion of POTS in COVID-19 survival when presented with symptoms of autonomic dysfunction and should conduct diagnostic tests like the Tilt table and others to confirm it. The management of COVID-19-related POTS requires a comprehensive approach. Most patients respond to initial non-pharmacological options, but when the symptoms become more severe and they do not respond to the non-pharmacological approach, pharmacological options are considered. We have limited understanding and knowledge of post-COVID-19 POTS, and further research is warranted to improve our understanding and formulate a better management plan.
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Deng J, Li H, Guo Y, Zhang G, Fischer H, Stavrakis S, Yu X. Transcutaneous vagus nerve stimulation attenuates autoantibody-mediated cardiovagal dysfunction and inflammation in a rabbit model of postural tachycardia syndrome. J Interv Card Electrophysiol 2023; 66:291-300. [PMID: 35118574 PMCID: PMC9349471 DOI: 10.1007/s10840-022-01144-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/30/2022] [Indexed: 12/12/2022]
Abstract
PURPOSE Previous studies demonstrated M2 muscarinic acetylcholine receptor-activating autoantibodies (M2R-AAb) were present in some patients with postural tachycardia syndrome (POTS). This study examines how these autoantibodies might contribute to the pathophysiology of POTS, and whether low-level tragus stimulation (LLTS) can ameliorate autoantibody-mediated autonomic dysregulation in the rabbit. METHODS Five New Zealand white rabbits were immunized with a M2R second extracellular loop peptide to produce cholinomimetic M2R-AAb. Tilt test and infusion studies were performed on conscious rabbits before immunization, 6 weeks after immunization, and 8 weeks after immunization with 2-week daily LLTS treatment. Each rabbit served as its own control. RESULTS Compared to preimmune state, an enhanced heart rate increase and decreased parasympathetic activity upon tilting were observed in immunized rabbits. Furthermore, these rabbits demonstrated an attenuated heart rate-slowing response to infusion of the M2R orthosteric agonist arecaidine propargyl ester (APE), suggesting an inhibitory allosteric effect of M2R-AAb. There was also a significant increase in serum inflammatory cytokines in immunized rabbits. LLTS treatment suppressed the postural tachycardia, improved the sympathovagal balance with increased acetylcholine secretion, reduced the levels of inflammatory cytokines, and reversed the attenuated heart rate response to APE in immunized rabbits. No suppression of M2R-AAb expression by LLTS was found during this short-term study period. Receptor-modulating activity of M2R-AAb produced in immunized rabbits was confirmed with in vitro bioassay. CONCLUSIONS Autoantibody inhibition of cholinergic ligand activity may be involved in the development of cardiovagal dysfunction and inflammation associated with POTS, both of which can be improved by vagal stimulation.
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Affiliation(s)
- Jielin Deng
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA
| | - Hongliang Li
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA
| | - Yankai Guo
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA
| | - Gege Zhang
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA
| | - Hayley Fischer
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA
| | - Stavros Stavrakis
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA
| | - Xichun Yu
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73117, USA.
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Bačkorová B, Lazúrová I. Selected biomarkers of orthostatic intolerance. VNITRNI LEKARSTVI 2023; 69:15-19. [PMID: 37827818 DOI: 10.36290/vnl.2023.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Orthostatic intolerance (OI) is defined as a group of diseases which symptoms are typically manifested in a standing position. These symptoms result from cerebral hypoperfusion and disappear in the supine position. We include postural orthostatic intolerance syndrome (POTS), orthostatic hypotension (OH) and vasovagal orthostatic syncope in this group of diseases. Each of them have similar clinical presentation (blurred vision, weakness, dizziness, nausea, headaches, fatigue). However, they vary from each other in biochemical, autonomic and hemodynamic characteristics. The aim of the work is to provide an overview of humoral and non-human markers that are involved in the etiopathogenesis of orthostatic intolerance.
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Lin J, Shen J, Liu J, Cheng W, Li L, Jiao F. Whole-Blood MicroRNA Sequence Profiling and Identification of Specific miR-21 for Adolescents With Postural Tachycardia Syndrome. Front Neurosci 2022; 16:920477. [PMID: 35844239 PMCID: PMC9281551 DOI: 10.3389/fnins.2022.920477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/23/2022] [Indexed: 11/23/2022] Open
Abstract
Objective The aim of the study was to establish whether whole-blood microRNA (miRNA) profiles differ between postural tachycardia syndrome (POTS) sufferers and control subjects and to identify the miRNA that regulates plasma H2S. Study Design High-throughput sequencing was used to obtain whole-blood miRNA expression profiles for 20 POTS sufferers and 20 normal children.The thresholds for defining differentially expressed miRNAs (DEmiRNAs) were an adjusted DESeq P of <0.05 and a log2 fold variation of ≥3. The DEmiRNA target genes were identified using RNAhybrid and miRanda, and only those identified by both were considered. The combined effects of the DEmiRNAs were determined using KEGG pathway analysis. Another 40 POTS and 20 normal patients were used as validation subjects. Plasma H2S was determined with a sulfide electrode, and flow-mediated vasodilation (FMD) was performed with a color Doppler ultrasound system. miRNAs were analyzed using qRT-PCR. Results Totally, 13 DEmiRNAs were identified through high-throughput sequencing. In the 60-member validation group, the 13 miRNAs were verified again, and it turned out that miR-21 was significantly elevated and could diagnose POTS with a 100% specificity and 92.5% sensitivity. Overall, 198 and 481 genes, respectively, were shown to be targeted by the 13 DEmiRNAs when P values of 0.01 and 0.05 were used. The target gene of hsa-miR-21-5p was SP1 when the P-value is <0.01. DEmiRNAs were significantly enriched in 36 pathways (P < 0.05), in which PI3K/Akt signaling was closely related to vascular function. In the validation subjects, the plasma H2S and FMD were higher in the POTS sufferers (P < 0.05). Conclusion Elevated whole-blood miR-21 levels serve as an indicator for POTS and may explain the increased plasma H2S observed in POTS sufferers.
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Affiliation(s)
- Jing Lin
- Key Laboratory for Disease Prevention and Control and Health Promotion of Shaanxi Province, School of Public Health, Xi'an Jiaotong University, Xi'an, China
- *Correspondence: Jing Lin
| | - Jie Shen
- Department of Cardiology, National Clinical Research Center for Child Health, Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Juan Liu
- Department of Pediatrics, Shenmu County Hospital, Yulin, China
| | - Wenjie Cheng
- School of Public Health, Xi'an Jiaotong University, Xi'an, China
| | - Lintian Li
- School of Public Health, Xi'an Jiaotong University, Xi'an, China
| | - Fuyong Jiao
- Department of Pediatrics, The Third Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
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Vernino S, Bourne KM, Stiles LE, Grubb BP, Fedorowski A, Stewart JM, Arnold AC, Pace LA, Axelsson J, Boris JR, Moak JP, Goodman BP, Chémali KR, Chung TH, Goldstein DS, Diedrich A, Miglis MG, Cortez MM, Miller AJ, Freeman R, Biaggioni I, Rowe PC, Sheldon RS, Shibao CA, Systrom DM, Cook GA, Doherty TA, Abdallah HI, Darbari A, Raj SR. Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting - Part 1. Auton Neurosci 2021; 235:102828. [PMID: 34144933 DOI: 10.1016/j.autneu.2021.102828] [Citation(s) in RCA: 108] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/10/2021] [Accepted: 05/30/2021] [Indexed: 12/13/2022]
Abstract
Postural orthostatic tachycardia syndrome (POTS) is a chronic and often disabling disorder characterized by orthostatic intolerance with excessive heart rate increase without hypotension during upright posture. Patients often experience a constellation of other typical symptoms including fatigue, exercise intolerance and gastrointestinal distress. A typical patient with POTS is a female of child-bearing age, who often first displays symptoms in adolescence. The onset of POTS may be precipitated by immunological stressors such as a viral infection. A variety of pathophysiologies are involved in the abnormal postural tachycardia response; however, the pathophysiology of the syndrome is incompletely understood and undoubtedly multifaceted. Clinicians and researchers focused on POTS convened at the National Institutes of Health in July 2019 to discuss the current state of understanding of the pathophysiology of POTS and to identify priorities for POTS research. This article, the first of two articles summarizing the information discussed at this meeting, summarizes the current understanding of this disorder and best practices for clinical care. The evaluation of a patient with suspected POTS should seek to establish the diagnosis, identify co-morbid conditions, and exclude conditions that could cause or mimic the syndrome. Once diagnosed, management typically begins with patient education and non-pharmacologic treatment options. Various medications are often used to address specific symptoms, but there are currently no FDA-approved medications for the treatment of POTS, and evidence for many of the medications used to treat POTS is not robust.
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Affiliation(s)
- Steven Vernino
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Kate M Bourne
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Lauren E Stiles
- Department of Neurology, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA; Dysautonomia International, East Moriches, NY, USA
| | - Blair P Grubb
- Division of Cardiology, Department of Medicine, The University of Toledo Medical Center, USA
| | - Artur Fedorowski
- Department of Clinical Sciences, Lund University, Malmö, Sweden; Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Julian M Stewart
- Center for Hypotension, Departments of Pediatrics and Physiology, New York Medical College, Valhalla, NY, USA
| | - Amy C Arnold
- Department of Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, PA, USA; Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Laura A Pace
- Center for Genomic Medicine and Department of Pediatrics, Division of Medical Genetics and Genomics, University of Utah, Salt Lake City, UT, USA
| | - Jonas Axelsson
- Department of Clinical Immunology, Karolinska University Hospital, Stockholm, Sweden
| | | | - Jeffrey P Moak
- Department of Pediatrics, George Washington Univeristy School of Medicine and Health Sciences, Washington, DC, USA
| | - Brent P Goodman
- Neuromuscular Division, Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA
| | - Kamal R Chémali
- Department of Neurology, Eastern Virginia Medical School, Division of Neurology, Neuromuscular and Autonomic Center, Sentara Healthcare, Norfolk, VA, USA
| | - Tae H Chung
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David S Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Andre Diedrich
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine and Biomedical Engineering, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mitchell G Miglis
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Melissa M Cortez
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Amanda J Miller
- Department of Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Roy Freeman
- Department of Neurology, Harvard Medical School, Boston, MA, USA; Center for Autonomic and Peripheral Nerve Disorders, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Italo Biaggioni
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Departments of Medicine and Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Peter C Rowe
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert S Sheldon
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Cyndya A Shibao
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Departments of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - David M Systrom
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Glen A Cook
- Department of Neurology, Uniformed Services University, Bethesda, MD, USA
| | - Taylor A Doherty
- Division of Rheumatology, Allergy, and Immunology, Department of Medicine, University of California at San Diego, La Jolla, CA, USA
| | | | - Anil Darbari
- Pediatric Gastroenterology, Children's National Hospital, Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Satish R Raj
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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van Campen CLMC, Rowe PC, Visser FC. Deconditioning does not explain orthostatic intolerance in ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome). J Transl Med 2021; 19:193. [PMID: 33947430 PMCID: PMC8097965 DOI: 10.1186/s12967-021-02819-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 04/08/2021] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Orthostatic intolerance (OI) is a frequent finding in individuals with myalgic encephalomyelitis /chronic fatigue syndrome (ME/CFS). Published studies have proposed that deconditioning is an important pathophysiological mechanism in various forms of OI, including postural orthostatic tachycardia syndrome (POTS), however conflicting opinions exist. Deconditioning can be classified objectively using the predicted peak oxygen consumption (VO2) values from cardiopulmonary exercise testing (CPET). Therefore, if deconditioning is an important contributor to OI symptomatology, one would expect a relation between the degree of reduction in peak VO2during CPET and the degree of reduction in CBF during head-up tilt testing (HUT). METHODS AND RESULTS In 22 healthy controls and 199 ME/CFS patients were included. Deconditioning was classified by the CPET response as follows: %peak VO2 ≥ 85% = no deconditioning, %peak VO2 65-85% = mild deconditioning, and %peak VO2 < 65% = severe deconditioning. HC had higher oxygen consumption at the ventilatory threshold and at peak exercise as compared to ME/CFS patients (p ranging between 0.001 and < 0.0001). Although ME/CFS patients had significantly greater CBF reduction than HC (p < 0.0001), there were no differences in CBF reduction among ME/CFS patients with no, mild, or severe deconditioning. We classified the hemodynamic response to HUT into three categories: those with a normal heart rate and blood pressure response, postural orthostatic tachycardia syndrome, or orthostatic hypotension. No difference in the degree of CBF reduction was shown in those three groups. CONCLUSION This study shows that in ME/CFS patients orthostatic intolerance is not caused by deconditioning as defined on cardiopulmonary exercise testing. An abnormal high decline in cerebral blood flow during orthostatic stress was present in all ME/CFS patients regardless of their %peak VO2 results on cardiopulmonary exercise testing.
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Affiliation(s)
| | - Peter C Rowe
- Department of Paediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Frans C Visser
- Stichting CardioZorg, Planetenweg 5, 2132 HN, Hoofddorp, Netherlands
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Garland EM, Gamboa A, Nwazue VC, Celedonio JE, Paranjape SY, Black BK, Okamoto LE, Shibao CA, Biaggioni I, Robertson D, Diedrich A, Dupont WD, Raj SR. Effect of High Dietary Sodium Intake in Patients With Postural Tachycardia Syndrome. J Am Coll Cardiol 2021; 77:2174-2184. [PMID: 33926653 DOI: 10.1016/j.jacc.2021.03.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND High sodium intake is recommended for the treatment of postural tachycardia syndrome (POTS) to counteract the hypovolemia and elevated plasma norepinephrine that contribute to excessive orthostatic tachycardia, but evidence of its efficacy is not available. OBJECTIVES This study tested whether a high sodium (HS) diet reduces orthostatic tachycardia (Δ heart rate) and upright heart rate compared with a low sodium (LS) diet in POTS patients, and secondarily its effect on plasma volume (PV) and plasma norepinephrine. METHODS A total of 14 POTS patients and 13 healthy control subjects (HC), age 23 to 49 years, were enrolled in a crossover study with 6 days of LS (10 mEq sodium/day) or HS (300 mEq sodium/day) diet. Supine and standing heart rate, blood pressure, serum aldosterone, plasma renin activity, blood volume, and plasma norepinephrine and epinephrine were measured. RESULTS In POTS, the HS diet reduced upright heart rate and Δ heart rate compared with the LS diet. Total blood volume and PV increased, and standing norepinephrine decreased with the HS compared with the LS diet. However, upright heart rate, Δ heart rate, and upright norepinephrine remained higher in POTS than in HC on the HS diet (median 117 beats/min [interquartile range: 98 to 121 beats/min], 46 beats/min [interquartile range: 32 to 55 beats/min], and 753 pg/ml [interquartile range: 498 to 919 pg/ml] in POTS vs. 85 beats/min [interquartile range: 77 to 95 beats/min], 19 beats/min [interquartile range: 11 to 32 beats/min], and 387 pg/ml [interquartile range: 312 to 433 pg/ml] in HC, respectively), despite no difference in the measured PV. CONCLUSIONS In POTS patients, high dietary sodium intake compared with low dietary sodium intake increases plasma volume, lowers standing plasma norepinephrine, and decreases Δ heart rate. (Dietary Salt in Postural Tachycardia Syndrome; NCT01547117).
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Affiliation(s)
- Emily M Garland
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Alfredo Gamboa
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Victor C Nwazue
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jorge E Celedonio
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sachin Y Paranjape
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Bonnie K Black
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Luis E Okamoto
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Cyndya A Shibao
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Italo Biaggioni
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - David Robertson
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - André Diedrich
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Biomedical Engineering, School of Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - William D Dupont
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Satish R Raj
- Vanderbilt Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
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Inflammatory Biomarkers in Postural Orthostatic Tachycardia Syndrome with Elevated G-Protein-Coupled Receptor Autoantibodies. J Clin Med 2021; 10:jcm10040623. [PMID: 33562074 PMCID: PMC7914580 DOI: 10.3390/jcm10040623] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 01/28/2021] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
A growing body of evidence suggests that postural orthostatic tachycardia syndrome (POTS) may be an autoimmune disorder. We have reported in a previous manuscript that 89% of POTS patients (n = 55) had elevations in G-protein-coupled adrenergic A1 receptor autoantibodies and 53% had elevations in muscarinic acetylcholine M4 receptor autoantibodies, as assessed by ELISA. Patients with autoimmune disorders have been reported with a variety of elevated cytokines and cytokines (such as rheumatoid arthritis); thus, we evaluated a limited number of cytokines/chemokines in POTS patients with elevated adrenergic and muscarinic receptor autoantibodies. We utilized the plasma of 34 patients from a previous study; all of the patients (100%) had autoantibodies against the A1 adrenergic receptor and 55.9% (19/34) had autoantibodies against the M4 muscarinic acetylcholine receptor. In particular, the plasma cytokine/chemokine levels were measured as biomarkers of inflammation by Quantibody® technology (Raybiotech, Peachtree Corners, GA, USA). We also evaluated the platelet dense granule numbers, as these patients frequently complain of symptoms related to platelet dysfunction. Patients were predominantly young females who displayed a multitude of co-morbidities but generally reported viral-like symptoms preceding episodes of syncope. Eighty five percent (29/34) had platelet storage pool deficiency. Patients had elevations in five of ten cytokine/chemokines biomarkers (IL1β, IL21, TNFα, INFγ, and CD30), whereas two biomarkers had decreased levels (CD40L and RANTES). Our observations demonstrate that POTS patients known to have autoantibodies against the G-protein-coupled adrenergic A1 receptor have abnormal plasma concentrations of inflammatory cytokines.
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Chopoorian AH, Wahba A, Celedonio J, Nwazue V, Smith EC, Garland EM, Paranjape S, Okamoto LE, Black BK, Biaggioni I, Raj SR, Gamboa A. Impaired Endothelial Function in Patients With Postural Tachycardia Syndrome. Hypertension 2021; 77:1001-1009. [PMID: 33486983 DOI: 10.1161/hypertensionaha.120.16238] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
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, P=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, P=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.
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Affiliation(s)
- Abby H Chopoorian
- From the Vanderbilt University School of Medicine (A.H.C.), Vanderbilt University Medical Center, Nashville, TN
| | - Amr Wahba
- 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
| | - Jorge Celedonio
- 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
| | - Victor Nwazue
- 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
| | - Emily C Smith
- 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
| | - Emily M Garland
- 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
| | - Sachin Paranjape
- 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
| | - Luis E Okamoto
- 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
| | - Bonnie K Black
- 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
| | - Italo Biaggioni
- 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.,Department of Pharmacology, Vanderbilt University, Nashville, TN (I.B.)
| | - Satish R Raj
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Alberta, Canada (S.R.R.)
| | - Alfredo Gamboa
- 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
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Kesserwani H. Postural Orthostatic Tachycardia Syndrome Misdiagnosed as Anxiety: A Case Report with a Review of Therapy and Pathophysiology. Cureus 2020; 12:e10881. [PMID: 33178533 PMCID: PMC7652348 DOI: 10.7759/cureus.10881] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Dizziness can be protean with multiple phenotypes. One common phenotype in the young population is postural orthostatic tachycardia syndrome (POTS). POTS has a unique cardiovascular signature with a fascinating range of etiologies and pharmacodynamic substrates. This condition can pass undiagnosed for many years and is often mistaken as an anxiety disorder due to some of its hyperadrenergic manifestations. We present one such case and then flesh out the treatment strategies, both conservative and pharmacologic. We finally describe the various underlying pathophysiologic mechanisms of POTS and its sub-types and outline the various aberrant cardiovascular reflexes. We also describe the power spectra of the heart rate variability frequency bands and their underlying physiologic basis.
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Abstract
INTRODUCTION Postural tachycardia syndrome is more frequently being recognised in adolescents and adults. However, its pathophysiology remains undefined. We evaluated our database for patterns in family history of clinical symptoms and associated disorders in these patients. MATERIALS AND METHODS Patients with postural tachycardia syndrome diagnosed in our clinic between 2014 and 2018 and who were less than 19 years at diagnosis were included. The history was reviewed for family members with postural tachycardia syndrome, dizziness and/or syncope, joint hypermobility with or without hypermobile Ehlers-Danlos syndrome, and autoimmune disorders. Statistical analysis assessed the entire cohort plus differences in gender, presence or absence of joint hypermobility, and presence or absence of familial autoimmune disease. RESULTS A total of 579 patients met inclusion criteria. We found that 14.2% of patients had a family member with postural tachycardia syndrome, with male patients more likely to have an affected family member (20% versus 12.7%, p = 0.04). If the patient also had joint hypermobility, male patients were more likely to have a family member with postural tachycardia syndrome (25% versus 12.6%, p = 0.017), more than one affected family member (7.1% versus 0.74%, p = 0.001), and a family member with joint hypermobility (37.5% versus 23.7%, p = 0.032). Autoimmune disease was seen in 45.1% of family members, but more likely in female patients with concurrent hypermobility (21.1% versus 8.9%, p = 0.035). DISCUSSION This in-depth analysis of associated familial disorders in patients with postural tachycardia syndrome offers further insight into the pathophysiology of the disorder, and informs further screening of family members in these patients.
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Abstract
Postural orthostatic tachycardia syndrome (POTS) is a clinically heterogeneous disorder with multiple contributing pathophysiologic mechanisms manifesting as symptoms of orthostatic intolerance in the setting of orthostatic tachycardia (increase in heart rate by at least 30 beats per minute upon assuming an upright position) without orthostatic hypotension. The three major pathophysiologic mechanisms include partial autonomic neuropathy, hypovolemia, and hyperadrenergic state. Patients often will exhibit overlapping characteristics from more than one of these mechanisms. The approach to the treatment of POTS centers on treating the underlying pathophysiologic mechanism. Stockings, abdominal binders, and vasoconstrictors are used to enhance venous return in partial neuropathic POTS. Exercise and volume expansion are the main treatment strategies for hypo-volemic POTS. For hyperadrenergic POTS, beta-blockers and avoidance of norepinephrine reuptake inhibitors is important. Attempts should be made to discern which pathophysiologic mechanism(s) may be afflicting patients so that treatment regimens can be individualized.
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Affiliation(s)
- Philip L. Mar
- Division of Cardiology, Department of Medicine, St. Louis University School of Medicine, St. Louis, Missouri 63110, USA
| | - Satish R. Raj
- Libin Cardiovascular Institute of Alberta, Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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Boris JR, McClain ZBR, Bernadzikowski T. Clinical Course of Transgender Adolescents with Complicated Postural Orthostatic Tachycardia Syndrome Undergoing Hormonal Therapy in Gender Transition: A Case Series. Transgend Health 2019; 4:331-334. [PMID: 31754630 PMCID: PMC6868651 DOI: 10.1089/trgh.2019.0041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Purpose: Postural orthostatic tachycardia syndrome (POTS), an increasingly recognized dysautonomia, may affect as many as 3,000,000 Americans. Concurrently, prevalence estimates suggest 10% of individuals identify as lesbian, gay, bisexual, transgender, or questioning/queer. The preponderance of female POTS patients implies hormonal differences between natal sexes and their role in POTS. Transgender POTS patients using hormone therapies may offer further insight into the mechanism of POTS. There have been no previously published studies of transgender patients with POTS undergoing gender-affirming hormone therapy. Methods: We reviewed our electronic health record for clinical histories of transgender patients in our POTS Database. Results: Three patients who transitioned from female to male demonstrated clinical improvement of their POTS symptoms with the addition of testosterone therapy. Conclusion: We present our clinical experience of three transgender POTS patients who transitioned from female to male with hormone therapy, all of whom demonstrated clinical improvement with testosterone. This may give further insight into the pathophysiology of POTS. However, the authors do not endorse the use of hormone therapy as primary therapy for the symptoms of POTS.
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Affiliation(s)
| | - Zachary B R McClain
- Division of Adolescent Medicine, Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Thomas Bernadzikowski
- Division of Radiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
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Jacob G, Diedrich L, Sato K, Brychta RJ, Raj SR, Robertson D, Biaggioni I, Diedrich A. Vagal and Sympathetic Function in Neuropathic Postural Tachycardia Syndrome. Hypertension 2019; 73:1087-1096. [PMID: 30879357 DOI: 10.1161/hypertensionaha.118.11803] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The diagnosis of neuropathic postural tachycardia syndrome (POTS) requires research techniques not available clinically. We hypothesized that these patients will have impaired vagal and sympathetic cardiovascular control that can be characterized with clinical autonomic tests. We included 12 POTS patients with possible neuropathic subtype because of normal plasma norepinephrine and no increase in upright blood pressure. We compared them to 10 healthy subjects. We assessed hemodynamics, heart rate and blood pressure variability, baroreflex sensitivity, raw and integrated muscle sympathetic nerve activity, and blood volume. To understand the vagal/sympathetic control, we dissected the phase 2 of Valsalva maneuver (VM) into early (VM2e) and late (VM2l). POTS' upright heart rate increased 43±3 bpm. Patients had normal plasma volume but reduced red blood cell volume (1.29 L versus predicted normal values 1.58 L; P=0.02). Vagal indices of heart rate variability, HFRRI (430±130 versus 1680±900; P=0.04), PNN50, and root mean squared of successive differences were lower in POTS. Patients showed a decrease in vagal baroreflex sensitivity (VM2e; P=0.04). In POTS, integrated muscle sympathetic nerve activity was lower at rest (12±1.5 versus 20±2 burst/min; P=0.004) and raw muscle sympathetic nerve activity spike analysis showed blunted responses during VM2e, despite a greater drop in systolic blood pressure (34±5 in POTS and 14±6 mm Hg in controls; P=0.01). This cohort of POTS patients enriched for possible neuropathic subtype had lower resting muscle sympathetic nerve activity, impaired vagal cardiac control, and exaggerated drop in blood pressure in response to VM and a delay in the sympathetic cardiovascular responsiveness during hypotensive challenge.
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Affiliation(s)
- Giris Jacob
- From the Department of Medicine F & J. Recanati Autonomic Dysfunction Center, Tel Aviv "Sourasky" Medical Center and Sackler Faculty of Medicine, University of Tel Aviv, Israel (G.J.)
| | - Laura Diedrich
- US Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville (L.D.)
| | - Kyoko Sato
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN.,Department of Medicine, Tokyo Women's Medical University, Medical Center East, Japan (K.S.)
| | - Robert J Brychta
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (R.J.B.)
| | - Satish R Raj
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN
| | - David Robertson
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN.,Department of Neurology (D.R.), Vanderbilt University School of Medicine, Nashville, TN
| | - Italo Biaggioni
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN
| | - André Diedrich
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN.,Department of Biomedical Engineering (A.D.), Vanderbilt University School of Medicine, Nashville, TN
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Gunning WT, Kvale H, Kramer PM, Karabin BL, Grubb BP. Postural Orthostatic Tachycardia Syndrome Is Associated With Elevated G-Protein Coupled Receptor Autoantibodies. J Am Heart Assoc 2019; 8:e013602. [PMID: 31495251 PMCID: PMC6818019 DOI: 10.1161/jaha.119.013602] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Background The etiology of postural orthostatic tachycardia syndrome (POTS) is yet to be established. The disorder is often misdiagnosed as chronic anxiety or a panic disorder because the autonomic failure in these patients is not severe. A growing body of evidence suggests that POTS may be an autoimmune disorder. Antinuclear antibodies and elevations of ganglionic, adrenergic, and muscarinic acetylcholine receptor antibodies have all been reported. Methods and Results We collected detailed clinical symptoms of 55 patients diagnosed with POTS. We also evaluated serum levels of autoantibodies against 4 subtypes of G‐protein coupled adrenergic receptors and 5 subtypes of G‐protein coupled muscarinic acetylcholine receptors by ELISA. Our patients had a multitude of comorbidities, were predominantly young females, and reported viral‐like symptoms preceding episodes of syncope. We detected a significant number of patients with elevated levels of autoantibodies against the adrenergic alpha 1 receptor (89%) and against the muscarinic acetylcholine M4 receptor (53%). Surprisingly, elevations of muscarinic receptor autoantibodies appeared to be dependent upon elevation of autoantibodies against the A1 adrenergic receptor! Four patients had elevations of G‐protein coupled autoantibodies against all 9 receptor subtypes measured in our study. Five POTS patients had no elevation of any autoantibody; similarly, controls were also negative for autoantibody elevations. There was a weak correlation of clinical symptom severity with G‐protein coupled autoantibodies. Conclusions Our observations provide further evidence that, in most cases, POTS patients have at least 1 elevated G‐protein coupled adrenergic autoantibody and, in some instances, both adrenergic and muscarinic autoantibodies, supporting the hypothesis that POTS may be an autoimmune disorder.
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21
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Unexplained exertional intolerance associated with impaired systemic oxygen extraction. Eur J Appl Physiol 2019; 119:2375-2389. [PMID: 31493035 DOI: 10.1007/s00421-019-04222-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 08/28/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE The clinical investigation of exertional intolerance generally focuses on cardiopulmonary diseases, while peripheral factors are often overlooked. We hypothesize that a subset of patients exists whose predominant exercise limitation is due to abnormal systemic oxygen extraction (SOE). METHODS We reviewed invasive cardiopulmonary exercise test (iCPET) results of 313 consecutive patients presenting with unexplained exertional intolerance. An exercise limit due to poor SOE was defined as peak exercise (Ca-vO2)/[Hb] ≤ 0.8 and VO2max < 80% predicted in the absence of a cardiac or pulmonary mechanical limit. Those with peak (Ca-vO2)/[Hb] > 0.8, VO2max ≥ 80%, and no cardiac or pulmonary limit were considered otherwise normal. The otherwise normal group was divided into hyperventilators (HV) and normals (NL). Hyperventilation was defined as peak PaCO2 < [1.5 × HCO3 + 6]. RESULTS Prevalence of impaired SOE as the sole cause of exertional intolerance was 12.5% (32/257). At peak exercise, poor SOE and HV had less acidemic arterial blood compared to NL (pHa = 7.39 ± 0.05 vs. 7.38 ± 0.05 vs. 7.32 ± 0.02, p < 0.001), which was explained by relative hypocapnia (PaCO2 = 29.9 ± 5.4 mmHg vs. 31.6 ± 5.4 vs. 37.5 ± 3.4, p < 0.001). For a subset of poor SOE, this relative alkalemia, also seen in mixed venous blood, was associated with a normal PvO2 nadir (28 ± 2 mmHg vs. 26 ± 4, p = 0.627) but increased SvO2 at peak exercise (44.1 ± 5.2% vs. 31.4 ± 7.0, p < 0.001). CONCLUSIONS We identified a cohort of patients whose exercise limitation is due only to systemic oxygen extraction, due to either an intrinsic abnormality of skeletal muscle mitochondrion, limb muscle microcirculatory dysregulation, or hyperventilation and left shift the oxyhemoglobin dissociation curve.
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22
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Blitshteyn S, Brinth L, Hendrickson JE, Martinez-Lavin M. Autonomic dysfunction and HPV immunization: an overview. Immunol Res 2019; 66:744-754. [PMID: 30478703 DOI: 10.1007/s12026-018-9036-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This article reviews the case series reported from several countries describing patients with suspected severe side effects to the HPV vaccines. The described symptom clusters are remarkably similar and include disabling fatigue, headache, widespread pain, fainting, gastrointestinal dysmotility, limb weakness, memory impairment episodes of altered awareness, and abnormal movements. This constellation of symptoms and signs has been labeled with different diagnoses such as complex regional pain syndrome (CRPS), postural orthostatic tachycardia syndrome (POTS), small fiber neuropathy (SFN), myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), or fibromyalgia. It is known that autoimmunity and autoantibodies are present in a subset of patients with CRPS, POTS, SFN, ME/CFS, and fibromyalgia. This article proposes that vaccine-triggered, immune-mediated autonomic dysfunction could lead to the development of de novo post-HPV vaccination syndrome possibly in genetically susceptible individuals. Being cognizant that a temporal relationship between vaccination and symptom onset does not necessarily equate to causality, mounting evidence of case series calls for well-designed case-control studies to determine the prevalence and possible causation between these symptom clusters and HPV vaccines. Since personalized medicine is gaining momentum, the use of adversomics and pharmacogenetics may eventually help identify individuals who are predisposed to HPV vaccine adverse events.
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Affiliation(s)
- Svetlana Blitshteyn
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Louise Brinth
- Syncope Unit, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Jeanne E Hendrickson
- Laboratory Medicine and Pediatrics, Yale University School of Medicine, New Haven, CT, USA
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23
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Miglis MG, Muppidi S. Do astronauts get postural tachycardia syndrome? And other updates on recent autonomic research. Clin Auton Res 2019; 29:263-265. [PMID: 31089931 DOI: 10.1007/s10286-019-00613-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 05/07/2019] [Indexed: 12/01/2022]
Affiliation(s)
- Mitchell G Miglis
- Stanford Neurosciences Health Center, 213 Quarry Road, 2nd Floor, Palo Alto, CA, 94304, USA
| | - Srikanth Muppidi
- Stanford Neurosciences Health Center, 213 Quarry Road, 2nd Floor, Palo Alto, CA, 94304, USA.
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24
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Cheema MA, Zain MA, Ullah W, Cheema K. Is ivabradine a wonder drug for atypical POTS? BMJ Case Rep 2019; 12:12/4/e227789. [PMID: 31005863 DOI: 10.1136/bcr-2018-227789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Syncope is a sudden loss and gain of consciousness. Traditionally, it is caused by the abnormalities of neurological, cardiac or vasovagal systems. We present a case of a 19-year-old woman presenting with recurrent syncopal episodes with no apparent cause. Examination and investigations were unremarkable for any aetiology except positive tilt tests for postural orthostatic tachycardia syndrome. The purpose of this report is to make physicians aware of the unique presentation of this rare aetiology with recurrent syncopal episodes and the novel management approach.
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Affiliation(s)
| | | | - Waqas Ullah
- Internal Medicine, Abington Hospital - Jefferson Health, Abington, PA, USA
| | - Khadija Cheema
- Internal Medicine, Abington Hospital - Jefferson Health, Abington, PA, USA
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25
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Bryarly M, Phillips LT, Fu Q, Vernino S, Levine BD. Postural Orthostatic Tachycardia Syndrome. J Am Coll Cardiol 2019; 73:1207-1228. [DOI: 10.1016/j.jacc.2018.11.059] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 11/01/2018] [Accepted: 11/05/2018] [Indexed: 12/26/2022]
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26
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Morgan K, Chojenta C, Tavener M, Smith A, Loxton D. Postural Orthostatic Tachycardia Syndrome during pregnancy: A systematic review of the literature. Auton Neurosci 2018; 215:106-118. [DOI: 10.1016/j.autneu.2018.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/27/2018] [Accepted: 05/07/2018] [Indexed: 01/25/2023]
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27
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Stiles LE, Cinnamon J, Balan I. The patient perspective: What postural orthostatic tachycardia syndrome patients want physicians to know. Auton Neurosci 2018; 215:121-125. [PMID: 29903594 DOI: 10.1016/j.autneu.2018.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 06/05/2018] [Accepted: 06/06/2018] [Indexed: 11/30/2022]
Abstract
Diagnosing and treating postural orthostatic tachycardia syndrome (POTS) can be a frustrating experience for patients and physicians alike. Experienced patient leaders solicited input from the large online POTS community to identify patient suggestions and concerns, with the goal of improving the patient-physician relationship and outcomes in POTS. This review article offers practical tips to improve POTS patient care and links to credible resources for your patients. The authors emphasize the urgent need for improved physician education, a tailored treatment approach, and expanded research efforts.
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Affiliation(s)
| | | | - Irina Balan
- Dysautonomia International, East Moriches, New York, USA
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28
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Abstract
OBJECTIVE The aim of this study was to identify and evaluate demographic and clinical features of paediatric patients with postural orthostatic tachycardia syndrome in a tertiary hospital speciality clinic. METHOD This is a retrospective review of clinical data obtained during initial outpatient evaluation. RESULTS A total of 708 patients met the evaluation criteria. Female patients outnumbered males, 3.45:1. Caucasians were over-represented at 94.1% of patients. Median age at diagnosis was 15.7 years. Joint hypermobility occurred in 57.3% of patients; 22.4% had hypermobile Ehlers-Danlos syndrome; and 34.9% had hypermobility spectrum disorder. Median age of onset of symptoms was 12.6 years in patients with hypermobility versus 13.7 years in those without (p=0.0001). Median duration of symptoms was 3.3 years with hypermobility versus 1.5 years without (p<0.00001). Putative triggers included infection in 23.6% of patients, concussion in 11.4%, and surgery/trauma in 2.8%. Concurrent inflammatory disorders were noted in 5.2% of patients. Six symptoms comprised 80% of initial patient complaints. Overall, 66% of patients subsequently had at least 10 symptoms, 50% had at least 14 symptoms, and 30% reported at least 26 symptoms. Symptoms were largely cardiovascular, gastrointestinal, and neurological. Paediatric patients with postural orthostatic tachycardia syndrome seen in a large speciality clinic are predominantly female, are mostly Caucasian, have onset of symptoms in early adolescence, and have symptoms for over two years before diagnosis. Over half of patients have joint hypermobility. More than one-third of patients have a possible autoimmune or inflammatory trigger, including infection, concussion, or surgery/trauma. Patients experience symptoms that are highly variable and multi-system in origin over the course of illness.
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Anjum I, Sohail W, Hatipoglu B, Wilson R. Postural Orthostatic Tachycardia Syndrome and Its Unusual Presenting Complaints in Women: A Literature Minireview. Cureus 2018; 10:e2435. [PMID: 29876157 PMCID: PMC5988200 DOI: 10.7759/cureus.2435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 03/26/2018] [Indexed: 01/26/2023] Open
Abstract
Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous disorder of the autonomic nervous system that is defined by symptoms of orthostatic intolerance. According to the current criteria for adults, currently, POTS is defined as a heart rate increment of 30 beats/minute or more after 10 minutes of standing in the absence of orthostatic hypotension. There is a vast majority that remains misdiagnosed due to the heterogeneity of the disorder. Due to a lack of Food and Drug Administration (FDA) approved therapy, alternative therapies and over the counter medications are used to alleviate the symptoms. This is an uncommon presentation observed primarily in women, as it is more prevalent in females.
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Affiliation(s)
- Ibrar Anjum
- Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, Houston, USA
| | - Wafa Sohail
- Dow Medical College, Dow University of Health Sciences (DUHS), Karachi, Pakistan
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30
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Yu X, Li H, Murphy TA, Nuss Z, Liles J, Liles C, Aston CE, Raj SR, Fedorowski A, Kem DC. Angiotensin II Type 1 Receptor Autoantibodies in Postural Tachycardia Syndrome. J Am Heart Assoc 2018; 7:JAHA.117.008351. [PMID: 29618472 PMCID: PMC6015435 DOI: 10.1161/jaha.117.008351] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Both the adrenergic and renin‐angiotensin systems contribute to orthostatic circulatory homeostasis, which is impaired in postural orthostatic tachycardia syndrome (POTS). Activating autoantibodies to the α1‐adrenergic and β1/2‐adrenergic receptors have previously been found in sera from patients with POTS. We hypothesized that patients with POTS might also harbor activating autoantibodies to the angiotensin II type 1 receptor (AT1R) independently of antiadrenergic autoimmunity. This study examines a possible pathophysiological role for AT1R autoantibodies in POTS. Methods and Results Serum immunoglobulin G from 17 patients with POTS, 6 patients with recurrent vasovagal syncope, and 10 normal controls was analyzed for the ability to activate AT1R and alter AT1R ligand responsiveness in transfected cells in vitro. Of 17 subjects with POTS, 12 demonstrated significant AT1R antibody activity in immunoglobulin G purified from their serum. No significant AT1R antibody activity was found in the subjects with vasovagal syncope or healthy subjects. AT1R activation by POTS immunoglobulin G was specifically blocked by the AT1R blocker losartan. Moreover, POTS immunoglobulin G significantly shifted the angiotensin II dosage response curve to the right, consistent with an inhibitory effect. All subjects with POTS were positive for one or both autoantibodies to the AT1R and α1‐adrenergic receptor. Conclusions Most patients with POTS harbor AT1R antibody activity. This supports the concept that AT1R autoantibodies and antiadrenergic autoantibodies, acting separately or together, may exert a significant impact on the cardiovascular pathophysiological characteristics in POTS.
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Affiliation(s)
- Xichun Yu
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
| | - Hongliang Li
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
| | - Taylor A Murphy
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
| | - Zachary Nuss
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
| | - Jonathan Liles
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
| | - Campbell Liles
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
| | - Christopher E Aston
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Satish R Raj
- Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta University of Calgary, Alberta, Canada.,Department of Medicine, Autonomic Dysfunction Center, Vanderbilt University, Nashville, TN
| | - Artur Fedorowski
- Department of Clinical Sciences, Lund University, Lund, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - David C Kem
- Department of Medicine, University of Oklahoma Health Sciences Center and VA Medical Center, Oklahoma City, OK
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31
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Recent advances in the understanding of the mechanisms underlying postural tachycardia syndrome in children: practical implications for treatment. Cardiol Young 2017; 27:413-417. [PMID: 27938459 DOI: 10.1017/s1047951116002559] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Postural tachycardia syndrome is defined by a heart rate increment of 40 beats/minute (bpm) (or a heart rate that exceeds 125 bpm) within 10 minutes of change from the supine position to an upright position in the absence of obvious orthostatic hypotension. There are multiple pathophysiological mechanisms that underlie postural tachycardia syndrome, including peripheral denervation, β-receptor supersensitivity, hypovolaemia, and impaired muscle pump. Some children afflicted with postural orthostatic tachycardia syndrome and hypovolaemic dysregulation have been found to have perturbed renin-angiotensin-aldosterone profile, disturbed vascular endothelial function, and abnormal vasodilation. The hyperadrenergic state in some postural tachycardia syndrome patients is likely a driver for orthostatic tachycardia. Other mechanisms include the presence of treatable autonomic neuropathies. An understanding of these pathophysiological mechanisms might be helpful for the effective treatment of postural tachycardia syndrome.
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32
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Lu W, Yan H, Wu S, Chen S, Xu W, Jin H, Du J. Electrocardiography-Derived Predictors for Therapeutic Response to Treatment in Children with Postural Tachycardia Syndrome. J Pediatr 2016; 176:128-33. [PMID: 27318378 DOI: 10.1016/j.jpeds.2016.05.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Revised: 03/23/2016] [Accepted: 05/10/2016] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To explore whether electrocardiography (ECG) variables could be used to predict responses to physical treatment in children with postural tachycardia syndrome (POTS). STUDY DESIGN Forty children with POTS and 32 healthy controls were enrolled in this study. General information and hemodynamic and supine ECG variables, including QT interval dispersion (QTd), were collected. The children with POTS received physical treatment and 3 months of follow-up. A receiver-operating characteristic curve was used to evaluate the value of ECG variables for predicting the effectiveness of physical treatment. RESULTS Compared with the healthy children, the children with POTS had longer baseline QTd and heart rate (HR)-corrected QTd (QTcd), but shorter minimum QT intervals (QTmin) and minimum HR-corrected QT intervals (P < .05). In children with POTS, responders to physical treatment had a longer baseline time between QRS complexes (RR) interval of minimum QT interval and a longer QTcd compared with nonresponders. A longer QTcd was a significant risk factor for the presence of POTS (OR, 1.022; P = .02) and for undesirable responses to physical treatment in children with POTS (OR, 1.044; P = .03). Baseline QTcd was positively correlated with the HR elevation from supine to upright seen in children with POTS (r = 0.348; P = .003). Receiver operating characteristic curve analysis demonstrated an area under the curve of 0.73, and using 43.0 msec as a cutoff of QTcd yielded a sensitivity of 90% and a specificity of 60%. CONCLUSION QTcd might be useful for predicting the effectiveness of physical treatment for POTS in children.
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Affiliation(s)
- Wenxin Lu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Hui Yan
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Shu Wu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Selena Chen
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
| | - Wenrui Xu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Hongfang Jin
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Junbao Du
- Department of Pediatrics, Peking University First Hospital, Beijing, China.
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Pstras L, Thomaseth K, Waniewski J, Balzani I, Bellavere F. The Valsalva manoeuvre: physiology and clinical examples. Acta Physiol (Oxf) 2016; 217:103-19. [PMID: 26662857 DOI: 10.1111/apha.12639] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 11/12/2015] [Accepted: 12/03/2015] [Indexed: 01/30/2023]
Abstract
The Valsalva manoeuvre (VM), a forced expiratory effort against a closed airway, has a wide range of applications in several medical disciplines, including diagnosing heart problems or autonomic nervous system deficiencies. The changes of the intrathoracic and intra-abdominal pressure associated with the manoeuvre result in a complex cardiovascular response with a concomitant action of several regulatory mechanisms. As the main aim of the reflex mechanisms is to control the arterial blood pressure (BP), their action is based primarily on signals from baroreceptors, although they also reflect the activity of pulmonary stretch receptors and, to a lower degree, chemoreceptors, with different mechanisms acting either in synergism or in antagonism depending on the phase of the manoeuvre. A variety of abnormal responses to the VM can be seen in patients with different conditions. Based on the arterial BP and heart rate changes during and after the manoeuvre several dysfunctions can be hence diagnosed or confirmed. The nature of the cardiovascular response to the manoeuvre depends, however, not only on the shape of the cardiovascular system and the autonomic function of the given patient, but also on a number of technical factors related to the execution of the manoeuvre including the duration and level of strain, the body position or breathing pattern. This review of the literature provides a comprehensive analysis of the physiology and pathophysiology of the VM and an overview of its applications. A number of clinical examples of normal and abnormal haemodynamic response to the manoeuvre have been also provided.
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Affiliation(s)
- L. Pstras
- Institute of Biocybernetics and Biomedical Engineering; Polish Academy of Sciences; Warsaw Poland
| | - K. Thomaseth
- Institute of Electronics, Computer and Telecommunication Engineering; National Research Council; Padua Italy
| | - J. Waniewski
- Institute of Biocybernetics and Biomedical Engineering; Polish Academy of Sciences; Warsaw Poland
| | - I. Balzani
- Department of Medicine; Sant'Antonio Hospital; Padua Italy
| | - F. Bellavere
- Provincial Agency for Health Services (APSS); Trento Italy
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Abstract
This article describes the pathophysiology, clinical presentation, differential diagnosis, diagnosis, and management of postural orthostatic tachycardia syndrome (POTS), a potentially debilitating autonomic disorder that can have many causes and presentations. POTS can be mistaken for panic disorder, inappropriate sinus tachycardia, and chronic fatigue syndrome. Clinician suspicion for the syndrome is key to prompt patient diagnosis and treatment.
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35
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Okamoto LE, Raj SR, Gamboa A, Shibao CA, Arnold AC, Garland EM, Black BK, Farley G, Diedrich A, Biaggioni I. Sympathetic activation is associated with increased IL-6, but not CRP in the absence of obesity: lessons from postural tachycardia syndrome and obesity. Am J Physiol Heart Circ Physiol 2015; 309:H2098-107. [PMID: 26453329 DOI: 10.1152/ajpheart.00409.2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 10/06/2015] [Indexed: 12/24/2022]
Abstract
Sympathetic activation is thought to contribute to the inflammatory process associated with obesity, which is characterized by elevated circulating C-reactive protein (hsCRP) and interleukin-6 (IL-6). To evaluate whether sympathetic activation is associated with inflammation in the absence of obesity, we studied patients with postural tachycardia syndrome (POTS), a condition characterized by increased sympathetic tone in otherwise healthy individuals. Compared with 23 lean controls, 43 lean female POTS had greater vascular sympathetic modulation (low-frequency blood pressure variability, LFSBP, 3.2 ± 0.4 vs. 5.5 ± 0.6 mmHg(2), respectively, P = 0.006), lower cardiac parasympathetic modulation (high-frequency heart rate variability, 1,414 ± 398 vs. 369 ± 66 ms(2), P = 0.001), and increased serum IL-6 (2.33 ± 0.49 vs. 4.15 ± 0.54 pg/ml, P = 0.011), but this was not associated with increases in hsCRP, which was low in both groups (0.69 ± 0.15 vs. 0.82 ± 0.16 mg/l, P = 0.736). To explore the contribution of adiposity to inflammation, we then compared 13 obese female POTS patients and 17 obese female controls to matched lean counterparts (13 POTS and 11 controls). Compared with lean controls, obese controls had increased LFSBP (3.3 ± 0.5 vs. 7.0 ± 1.1 mmHg(2); P = 0.016), IL-6 (2.15 ± 0.58 vs. 3.92 ± 0.43 pg/ml; P = 0.030) and hsCRP (0.69 ± 0.20 vs. 3.47 ± 0.72 mg/l; P = 0.001). Obese and lean POTS had similarly high IL-6 but only obese POTS had increased hsCRP (5.76 ± 1.99 mg/l vs. 0.65 ± 0.26; P < 0.001). In conclusion, sympathetic activation in POTS is associated with increased IL-6 even in the absence of obesity. The coupling between IL-6 and CRP, however, requires increased adiposity, likely through release of IL-6 by visceral fat.
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Affiliation(s)
- Luis E Okamoto
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Satish R Raj
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Pharmacology, Vanderbilt University School of Medicine; and
| | - Alfredo Gamboa
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Cyndya A Shibao
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Amy C Arnold
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Emily M Garland
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Bonnie K Black
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Ginnie Farley
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - André Diedrich
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Italo Biaggioni
- Vanderbilt Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; Department of Pharmacology, Vanderbilt University School of Medicine; and
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36
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Fu Q. Neuro-humoral control during orthostasis in health and disease. Front Physiol 2015; 5:521. [PMID: 25628571 PMCID: PMC4290528 DOI: 10.3389/fphys.2014.00521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/18/2014] [Indexed: 11/29/2022] Open
Affiliation(s)
- Qi Fu
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas Dallas, TX, USA ; Cardiology Division, Internal Medicine, University of Texas Southwestern Medical Center Dallas, TX, USA
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37
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Linnarsson D, Hughson RL, Fraser KS, Clément G, Karlsson LL, Mulder E, Paloski WH, Rittweger J, Wuyts FL, Zange J. Effects of an artificial gravity countermeasure on orthostatic tolerance, blood volumes and aerobic power after short-term bed rest (BR-AG1). J Appl Physiol (1985) 2014; 118:29-35. [PMID: 25342708 DOI: 10.1152/japplphysiol.00061.2014] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Exposure to artificial gravity (AG) in a short-arm centrifuge has potential benefits for maintaining human performance during long-term space missions. Eleven subjects were investigated during three campaigns of 5 days head-down bed rest: 1) bed rest without countermeasures (control), 2) bed rest and 30 min of AG (AG1) daily, and 3) bed rest and six periods of 5 min AG (AG2) daily. During centrifugation, the supine subjects were exposed to AG in the head-to-feet direction with 1 G at the center of mass. Subjects participated in the three campaigns in random order. The cardiovascular effects of bed rest and countermeasures were determined from changes in tolerance to a head-up tilt test with superimposed lower body negative pressure (HUT), from changes in plasma volume (PV) and from changes in maximum aerobic power (V̇o2 peak) during upright work on a cycle ergometer. Complete data sets were obtained in eight subjects. After bed rest, HUT tolerance times were 36, 64, and 78% of pre-bed rest baseline during control, AG1 and AG2, respectively, with a significant difference between AG2 and control. PV and V̇o2 peak decreased to 85 and 95% of pre-bed rest baseline, respectively, with no differences between the treatments. It was concluded that the AG2 countermeasure should be further investigated during future long-term bed rest studies, especially as it was better tolerated than AG1. The superior effect of AG2 on orthostatic tolerance could not be related to concomitant changes in PV or aerobic power.
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Affiliation(s)
- Dag Linnarsson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden;
| | - Richard L Hughson
- Schlegel-University of Waterloo Research Institute for Aging, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario, Canada
| | - Katelyn S Fraser
- Schlegel-University of Waterloo Research Institute for Aging, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario, Canada
| | - Gilles Clément
- International Space University, Illkirch-Graffenstaden, France
| | - Lars L Karlsson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Edwin Mulder
- Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany
| | - William H Paloski
- Neuroscience Research Laboratories, National Aeronautics and Space Administration/Johnson Space Center, Houston, Texas; Center for Neuromotor and Biomechanics Research, University of Houston, Houston, Texas
| | - Jörn Rittweger
- Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany; Institute for Biomedical Research into Human Movement and Health, Manchester Metropolitan University, Manchester, United Kingdom; and
| | - Floris L Wuyts
- Department of Otolaryngology, Antwerp University Research Center for Equilibrium and Aerospace, Antwerp, Belgium
| | - Jochen Zange
- Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany
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