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Richer L, Craig W, Linsdell M, Tang K, Zemek R. Autonomic Cardioregulatory Function Does Not Correlate With Symptom Improvement After Concussion in Children and Adolescents. J Neurotrauma 2024; 41:161-170. [PMID: 37310894 DOI: 10.1089/neu.2023.0113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Abstract
Although there is significant variability in the manifestations of persisting post-concussive symptoms (PPCS), autonomic dysfunction has been reported to contribute to PPCS and could serve as a biomarker of recovery. The objective of this study was to evaluate cardiac autonomic reflexes and autonomic function after concussion injury comparing those with prolonged concussion symptoms to those without. This is a case-control study where a non-referred population of concussed children or adolescent participants were enrolled from the Emergency Department (ED) of the Stollery Children's Hospital, a tertiary pediatric hospital in Edmonton, Alberta, Canada. Children and adolescents 8 through <18 years of age who presented with mild traumatic brain injury were diagnosed with concussion. Our study reported concussion symptoms and standardized clinical cardiac autonomic reflex testing at 4 and 12 weeks after injury. Our findings showed that 28 participants with concussion completed the 4-week follow-up questionnaires, and that 17 (61%) were diagnosed with PPCS. Difficulty concentrating, fatigue, noise sensitivity, light sensitivity, and headache were most commonly reported at baseline among those who were later diagnosed with PPCS. The mean change in heart rate (HR) with head-up tilt was 44.2 bpm (standard deviation [SD] 9.1) in the non-PPCS group and 46.6 bpm (SD 14.1) in the PPCS group at 4 weeks and was not significant in the unadjusted (p = 0.2) or adjusted analysis for age and female sex (p = 0.2). Overall, 70% (19/27) had significant orthostatic tachycardia >40 bpm, but PPCS and non-PPCS groups were similar. Similar results were observed among 23 participants at 12-week follow-up. The median maximum decrease in systolic blood pressure (SBP) with head-up tilt was -26.9 mm Hg (interquartile range [IQR] -32.6, -22.3) in the non-PPCS group and -25.1 mm Hg (IQR -32.2, -18.2) in the PPCS group, and was not significantly different in the unadjusted (p = 0.8) or adjusted (p = 0.8) analysis. Overall, 19 of 26 participants (73%) demonstrated orthostatic hypotension (SBP change >20 mm Hg) with no significant difference between the PPCS and non-PPCS groups. Similar results were observed at 12-week follow-up. In conclusion, cardiac autonomic reflex responses are abnormal in most children and adolescents with a concussion injury at 4- and 12-week follow-up and may reflect ongoing autonomic dysfunction. However, autonomic function did not differentiate PPCS, indicating that reported symptoms are not sensitive to autonomic abnormalities.
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Affiliation(s)
- Lawrence Richer
- Department of Pediatrics, Division of Neurology, University of Alberta, Edmonton, Alberta, Canada
| | - William Craig
- Department of Pediatrics, Stollery Children's Hospital, University of Alberta, Edmonton, Alberta, Canada
| | - Meghan Linsdell
- Women and Children's Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Ken Tang
- Independent Statistical Consultant
- Department of Pediatrics and Emergency Medicine, University of Ottawa, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada
| | - Roger Zemek
- Department of Pediatrics and Emergency Medicine, University of Ottawa, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada
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2
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Brassard P, Roy MA, Burma JS, Labrecque L, Smirl JD. Quantification of dynamic cerebral autoregulation: welcome to the jungle! Clin Auton Res 2023; 33:791-810. [PMID: 37758907 DOI: 10.1007/s10286-023-00986-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023]
Abstract
PURPOSE Patients with dysautonomia often experience symptoms such as dizziness, syncope, blurred vision and brain fog. Dynamic cerebral autoregulation, or the ability of the cerebrovasculature to react to transient changes in arterial blood pressure, could be associated with these symptoms. METHODS In this narrative review, we go beyond the classical view of cerebral autoregulation to discuss dynamic cerebral autoregulation, focusing on recent advances pitfalls and future directions. RESULTS Following some historical background, this narrative review provides a brief overview of the concept of cerebral autoregulation, with a focus on the quantification of dynamic cerebral autoregulation. We then discuss the main protocols and analytical approaches to assess dynamic cerebral autoregulation, including recent advances and important issues which need to be tackled. CONCLUSION The researcher or clinician new to this field needs an adequate comprehension of the toolbox they have to adequately assess, and interpret, the complex relationship between arterial blood pressure and cerebral blood flow in healthy individuals and clinical populations, including patients with autonomic disorders.
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Affiliation(s)
- Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.
- Research center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada.
| | - Marc-Antoine Roy
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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3
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Rodriguez B, Hochstrasser A, Eugster PJ, Grouzmann E, Müri RM, Z’Graggen WJ. Brain fog in neuropathic postural tachycardia syndrome may be associated with autonomic hyperarousal and improves after water drinking. Front Neurosci 2022; 16:968725. [PMID: 35992935 PMCID: PMC9388780 DOI: 10.3389/fnins.2022.968725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 07/19/2022] [Indexed: 11/18/2022] Open
Abstract
Background Brain fog is a common and highly disturbing symptom for patients with neuropathic postural tachycardia syndrome (POTS). Cognitive deficits have been measured exclusively in the upright body position and mainly comprised impairments of higher cognitive functions. The cause of brain fog is still unclear today. This study aimed to investigate whether increased autonomic activation might be an underlying mechanism for the occurrence of brain fog in neuropathic POTS. We therefore investigated cognitive function in patients with neuropathic POTS and a healthy control group depending on body position and in relation to catecholamine release as a sensitive indicator of acute stress. The second aim was to test the effect of water intake on cardiovascular regulation, orthostatic symptoms, cognitive function and catecholamine release. Methods Thirteen patients with neuropathic POTS and 15 healthy control subjects were included. All participants completed a total of four rounds of cognitive testing: two before and two after the intake of 500 ml still water, each first in the supine position and then during head-up tilt. At the end of each cognitive test, a blood sample was collected for determination of plasma catecholamines. After each head-up tilt phase participants were asked to rate their current symptoms on a visual analogue scale. Results Working memory performance in the upright body position was impaired in patients, which was associated with self-reported symptom severity. Patients had elevated plasma norepinephrine independent of body position and water intake that increased excessively in the upright body position. The excessive increase of plasma norepinephrine was related to heart rate and symptom severity. Water intake in patients decreased norepinephrine concentrations and heart rate, and improved symptoms as well as cognitive performance. Conclusion Brain fog and symptom severity in neuropathic POTS are paralleled by an excessive norepinephrine secretion. Bolus water drinking down-regulates norepinephrine secretion and improves general symptom severity including brain fog.
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Affiliation(s)
- Belén Rodriguez
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Annie Hochstrasser
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Philippe J. Eugster
- Service of Clinical Pharmacology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Eric Grouzmann
- Service of Clinical Pharmacology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - René M. Müri
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Gerontechnology and Rehabilitation Group, ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Werner J. Z’Graggen
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- *Correspondence: Werner J. Z’Graggen,
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4
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Natelson BH, Lin JMS, Blate M, Khan S, Chen Y, Unger ER. Physiological assessment of orthostatic intolerance in chronic fatigue syndrome. J Transl Med 2022; 20:95. [PMID: 35172863 PMCID: PMC8849016 DOI: 10.1186/s12967-022-03289-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 02/01/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Orthostatic intolerance-OI is common in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome-ME/CFS. We used a 10-min passive vertical lean test as orthostatic challenge-OC and measured changes in vitals and end tidal CO2 (eTCO2). An abnormal physiologic response to OC was identified in 60% of the 63 patients evaluated from one to three times over several years. Hypocapnia, either resting or induced by OC, was the most frequent abnormality, followed by postural orthostatic tachycardia. OBJECTIVE Evaluate the physiologic response of patients with ME/CFS to a standardized OC. DESIGN Respiratory and heart rate, blood pressure and eTCO2 were recorded twice at the end of 10-min supine rest and then every minute during the 10-min lean. Hypocapnia was eTCO2 ≤ 32 mmHg. Orthostatic tachycardia was heart rate increase ≥ 30 beats per minute compared with resting or ≥ 120 BPM. Orthostatic hypotension was decreased systolic pressure ≥ 20 mmHg from baseline. Tachypnea was respiratory rate of ≥ 20 breaths per minute-either supine or leaning. Questionnaire data on symptom severity, quality of life and mood were collected at visit #2. PATIENTS 63 consecutive patients fulfilling the 1994 case definition for CFS underwent lean testing at first visit and then annually at visit 2 (n = 48) and 3 (n = 29). MEASURES Supine hypocapnia; orthostatic tachycardia, hypocapnia or hypotension. RESULTS The majority of ME/CFS patients (60.3%, 38/63) had an abnormality detected during a lean test at any visit (51%, 50% and 45% at visits 1, 2 and 3, respectively). Hypocapnia at rest or induced by OC was more common and more likely to persist than postural orthostatic tachycardia. Anxiety scores did not differ between those with and without hypocapnia. CONCLUSIONS The 10-min lean test is useful in evaluation of OI in patients with ME/CFS. The most frequent abnormality, hypocapnia, would be missed without capnography.
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Affiliation(s)
- Benjamin H Natelson
- Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY, 10029, USA.
| | - Jin-Mann S Lin
- Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases, 1600 Clifton Road, Atlanta, GA, 30333, USA
| | - Michelle Blate
- Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY, 10029, USA
| | - Sarah Khan
- Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY, 10029, USA
| | - Yang Chen
- Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases, 1600 Clifton Road, Atlanta, GA, 30333, USA
| | - Elizabeth R Unger
- Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases, 1600 Clifton Road, Atlanta, GA, 30333, USA
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5
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Kharraziha I, Holm H, Bachus E, Melander O, Sutton R, Fedorowski A, Hamrefors V. Monitoring of cerebral oximetry in patients with postural orthostatic tachycardia syndrome. Europace 2020; 21:1575-1583. [PMID: 31384930 PMCID: PMC6877984 DOI: 10.1093/europace/euz204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 07/11/2019] [Indexed: 11/14/2022] Open
Abstract
AIMS Postural orthostatic tachycardia syndrome (POTS) is a disorder of unknown aetiology characterized by orthostatic intolerance and tachycardia with diverse other symptoms, including neurocognitive deficits. Cerebral oximetry non-invasively measures cerebral tissue saturation (SctO2) and has been shown to be informative in syncope evaluation. We aimed to assess SctO2 in POTS patients and those with normal response to orthostatic provocation, relative to haemodynamic parameters and symptoms. METHODS AND RESULTS Thirty-four patients with POTS (29.1 ± 9.5 years; 26 females) and 34 age-/sex-matched controls with normal head-up tilt tests (HUTs) were included. SctO2 at rest and during HUT were compared between POTS and controls. The relation between SctO2, systolic blood pressure (SBP), and heart rate (HR) during HUT was linearly assessed. SctO2 values were related to dizziness or syncope during HUT. The minimum SctO2-value during HUT was lower (65.4 ± 5.6 vs. 68.2 ± 4.2%, P = 0.023) and changes in SctO2 from supine to minimum HUT value were more pronounced in POTS patients (-5.7 ± 2.9% vs. -4.3 ± 2.1%, P = 0.028). Decrease in SBP from supine to minimum HUT value (P = 0.004) and increase in HR from supine to HUT value at 3 min (P = 0.022) correlated with more pronounced SctO2 decrease in POTS but not controls. SctO2 did not predict syncope or dizziness during HUT. CONCLUSION Postural orthostatic tachycardia syndrome patients have lower cerebral tissue saturation during orthostatic provocation compared with those subjects having normal haemodynamic response to tilt. Orthostatic decrease in cerebral saturation only weakly correlates with HR increase and does not predict vasovagal reflex in POTS. Other hitherto unknown factors may affect cerebral tissue saturation in POTS.
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Affiliation(s)
| | - Hannes Holm
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Erasmus Bachus
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Olle Melander
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
| | - Richard Sutton
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,National Heart and Lung Institute, Imperial College, Hammersmith Hospital Campus, London, UK
| | - Artur Fedorowski
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Viktor Hamrefors
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
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6
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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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7
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Olshansky B, Cannom D, Fedorowski A, Stewart J, Gibbons C, Sutton R, Shen WK, Muldowney J, Chung TH, Feigofsky S, Nayak H, Calkins H, Benditt DG. Postural Orthostatic Tachycardia Syndrome (POTS): A critical assessment. Prog Cardiovasc Dis 2020; 63:263-270. [PMID: 32222376 PMCID: PMC9012474 DOI: 10.1016/j.pcad.2020.03.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 03/22/2020] [Indexed: 02/07/2023]
Abstract
Although diagnostic criteria have been developed characterizing postural orthostatic tachycardia syndrome (POTS), no single set of criteria is universally accepted. Furthermore, there are gaps in the present criteria used to identify individuals who have this condition. The reproducibility of the physiological findings, the relationship of symptoms to physiological findings, the presence of symptoms alone without any physiological findings and the response to various interventions confuse rather than clarify this condition. As many disease entities can be confused with POTS, it becomes critical to identify what this syndrome is. What appears to be POTS may be an underlying condition that requires specific therapy. POTS is not simply orthostatic intolerance and symptoms or intermittent orthostatic tachycardia but the syndrome needs to be characterized over time and with reproducibility. Here we address critical issues regarding the pathophysiology and diagnosis of POTS in an attempt to arrive at a rational approach to categorize the syndrome with the hope that it may help both better identify individuals and better understand approaches to therapy.
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Affiliation(s)
- Brian Olshansky
- Division of Cardiology, The University of Iowa, Iowa City, IA, United States of America.
| | - David Cannom
- Division of Cardiovascular Medicine, Keck School of Medicine of USC, Los Angeles, CA, United States of America
| | - Artur Fedorowski
- Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Julian Stewart
- Center for Pediatric Hypotensive Disease, New York Medical College, Hawthorne, NY, United States of America
| | - Christopher Gibbons
- Department of Neurology, Harvard Medical School Beth Israel Deaconess Medical Center, Boston, MA, United States of America
| | - Richard Sutton
- Department of Cardiology, Hammersmith Hospital Campus, London, England, United Kingdom of Great Britain and Northern Ireland
| | - Win-Kuang Shen
- Department of Cardiovascular Diseases, Mayo Clinic Arizona Phoenix, AZ, United States of America
| | - James Muldowney
- Department of Cardiology, Hammersmith Hospital Campus, London, England, United Kingdom of Great Britain and Northern Ireland
| | - Tae Hwan Chung
- Department of Neurology, The Johns Hopkins Medical Institutions, Baltimore, MD, United States of America
| | - Suzy Feigofsky
- Iowa Heart Center, Carroll, IA, United States of America
| | - Hemal Nayak
- Division of Cardiology, Pritzker School of Medicine, University of Chicago, Chicago, IL, United States of America
| | - Hugh Calkins
- Division of Cardiology, The Johns Hopkins Medical Institutions, Baltimore, MD, United States of America
| | - David G Benditt
- University of Minnesota, Minneapolis, MN, United States of America
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8
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Kharraziha I, Holm H, Bachus E, Ricci F, Sutton R, Fedorowski A, Hamrefors V. Cerebral Oximetry in Syncope and Syndromes of Orthostatic Intolerance. Front Cardiovasc Med 2019; 6:171. [PMID: 31824964 PMCID: PMC6886369 DOI: 10.3389/fcvm.2019.00171] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 11/08/2019] [Indexed: 11/26/2022] Open
Abstract
Cerebral autoregulation is crucial for maintaining cerebral blood flow and perfusion. In recent years, the importance of cerebral oxygenation in syncope and orthostatic intolerance (OI) has received increased attention. Cerebral tissue oxygenation can be measured by using near-infrared spectroscopy (NIRS), which determines the ratio of oxygenated hemoglobin to total hemoglobin in cerebral tissue. NIRS is non-invasive technology using near-infrared light, which displays real-time cerebral tissue oxygenation. Normal values of cerebral tissue oxygenation in healthy subjects are 60 to 80%. Head-up tilt test (HUT) offers the opportunity to observe the haemodynamic changes precipitating syncope and is, today, the standard method for the evaluation of syncope and orthostatic intolerance syndromes. In previous studies where NIRS was applied during HUT, a significant decrease in cerebral tissue oxygenation both prior to and during loss-of-consciousness in vasovagal syncope (VVS) has been observed. Interestingly, cerebral tissue oxygenation appears to decrease even before haemodynamic changes can be observed. Apart from VVS, cerebral tissue oxygenation decreases during orthostatic provocation in patients with orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS), in the latter even in the absence of hypotension. Importantly, decline of cerebral tissue oxygenation in VVS and POTS during HUT may not correlate with hemodynamic changes. In this mini review, we summarize the current knowledge of the application of cerebral oximetry in syncope and orthostatic intolerance syndromes, discuss its likely value as a clinical diagnostic tool and also emphasize its potential in the understanding of the relevant pathophysiology.
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Affiliation(s)
- Isabella Kharraziha
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
| | - Hannes Holm
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Erasmus Bachus
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Fabrizio Ricci
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Institute of Cardiology, University "G. d'Annunzio", Chieti, Italy.,Department of Neuroscience and Imaging, ITAB - Institute Advanced Biomedical Technologies, University "G. d'Annunzio", Chieti, Italy
| | - Richard Sutton
- Department of Cardiology, Skåne University Hospital, Malmö, Sweden.,National Heart and Lung Institute, Imperial College, Hammersmith Hospital, London, United Kingdom
| | - Artur Fedorowski
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Viktor Hamrefors
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
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9
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Rodriguez B, Zimmermann R, Gutbrod K, Heinemann D, Z'Graggen WJ. Orthostatic Cognitive Dysfunction in Postural Tachycardia Syndrome After Rapid Water Drinking. Front Neurosci 2019; 13:327. [PMID: 31024242 PMCID: PMC6465605 DOI: 10.3389/fnins.2019.00327] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 03/21/2019] [Indexed: 11/13/2022] Open
Abstract
Background: Postural tachycardia syndrome (POTS) is a form of autonomic dysregulation and is characterized by an excessive heart rate (HR) increment upon the upright body position while blood pressure is maintained. Patients experience typical symptoms of orthostatic intolerance such as dizziness, nausea and cognitive impairments. The present study assessed position-dependent attentional and cognitive functioning in POTS patients compared to healthy subjects and tested the response of cognitive performance to acute water intake. Methods: Data was obtained from eight patients with neuropathic POTS and eight healthy subjects of similar age and gender. All participants completed questionnaires that assessed health-related quality of life and depression and underwent four rounds of neuropsychological testing overall, each before and after the intake of 500 ml still mineral water and both in the supine and in the upright posture. Results: Postural tachycardia syndrome patients showed deficits in working memory (WM) exclusively in the upright position compared to healthy subjects, but no position-dependent impairments in alertness or divided attention. Rapid water ingestion had a beneficial effect on WM in the upright posture, lead to a decrease in HR increment and to an improvement of subjective symptom experience. Conclusion: The results provide support for the occurrence of purely orthostatic cognitive deficits in POTS, especially when increased executive control and cognitive resources are required and document a favorable effect of water intake on cognitive performance. These findings have important implications for the management of cognitive symptoms in POTS as high water intake is an easy and accessible strategy.
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Affiliation(s)
- Belén Rodriguez
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Raya Zimmermann
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Klemens Gutbrod
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Doerthe Heinemann
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Werner J Z'Graggen
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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10
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Cutsforth-Gregory JK, Sandroni P. Clinical neurophysiology of postural tachycardia syndrome. HANDBOOK OF CLINICAL NEUROLOGY 2019; 161:429-445. [PMID: 31307619 DOI: 10.1016/b978-0-444-64142-7.00066-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Postural tachycardia syndrome (POTS) is one of several disorders of orthostatic intolerance (OI). It is defined by the development of symptoms of cerebral hypoperfusion or sympathetic activation and a sustained heart rate increment of 30 beats/min or more (40 beats/min for teenagers) within 10min of standing or head-up tilt in the absence of orthostatic hypotension; the standing heart rate is often 120 beats/min or higher. POTS is approximately five times more common in women than men. This heterogeneous syndrome is caused by several pathophysiologic mechanisms (limited autonomic neuropathy, hyperadrenergic state, hypovolemia, venous pooling, deconditioning), which are not mutually exclusive. Anxiety and somatic hypervigilance play significant roles in POTS. Common comorbidities include visceral pain and dysmotility, chronic fatigue and fibromyalgia, migraine, joint hypermobility, mitral valve prolapse, and inappropriate sinus tachycardia. Patients with suspected POTS should undergo comprehensive cardiac and neurologic examinations and autonomic and laboratory tests to determine the most likely pathophysiologic basis of OI. The objectives of POTS management are to (1) increase the time that patients can stand, perform daily activities, and exercise and (2) avoid syncope. Management involves nonpharmacologic (fluid and salt loading, physical countermaneuvers, compression garments, exercise training) and pharmacologic (β-blockers, pyridostigmine, fludrocortisone, midodrine) approaches.
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Affiliation(s)
| | - Paola Sandroni
- Department of Neurology, Mayo Clinic, Rochester, MN, United States.
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11
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Arnold AC, Ng J, Raj SR. Postural tachycardia syndrome - Diagnosis, physiology, and prognosis. Auton Neurosci 2018; 215:3-11. [PMID: 29523389 PMCID: PMC6113123 DOI: 10.1016/j.autneu.2018.02.005] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 02/22/2018] [Accepted: 02/25/2018] [Indexed: 11/29/2022]
Abstract
Postural tachycardia syndrome (POTS) is a heterogeneous clinical syndrome that has gained increasing interest over the past few decades due to its increasing prevalence and clinical impact on health-related quality of life. POTS is clinically characterized by sustained excessive tachycardia upon standing that occurs in the absence of significant orthostatic hypotension and other medical conditions and or medications, and with chronic symptoms of orthostatic intolerance. POTS represents one of the most common presentations of syncope and presyncope secondary to autonomic dysfunction in emergency rooms and in cardiology, neurology, and primary care clinics. The most sensitive method to detect POTS is a detailed medical history, physical examination with orthostatic vital signs or brief tilt table test, and a resting 12-lead electrocardiogram. Additional diagnostic testing may be warranted in selected patients based on clinical signs. While the precise etiology remains unknown, the orthostatic tachycardia in POTS is thought to reflect convergence of multiple pathophysiological processes, as a final common pathway. Based on this, POTS is often described as a clinical syndrome consisting of multiple heterogeneous disorders, with several underlying pathophysiological processes proposed in the literature including partial sympathetic neuropathy, hyperadrenergic state, hypovolemia, mast cell activation, deconditioning, and immune-mediated. These clinical features often overlap, however, making it difficult to categorize individual patients. Importantly, POTS is not associated with mortality, with many patients improving to some degree over time after diagnosis and proper treatment. This review will outline the current understanding of diagnosis, pathophysiology, and prognosis in POTS.
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Affiliation(s)
- Amy C Arnold
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, 500 University Drive, Mail Code H109, Hershey, PA, USA; Autonomic Dysfunction Center, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jessica Ng
- Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
| | - Satish R Raj
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada.
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Ha SY, Park KM, Park J, Kim SE, Lee BI, Shin KJ. Autonomic function test in progressive lacunar infarction. Acta Neurol Scand 2018; 138:32-40. [PMID: 29468632 DOI: 10.1111/ane.12913] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2018] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Neurological progression is a major problem in managing the patients with acute lacunar infarction. The purpose of this was to investigate whether autonomic dysfunction is associated with neurological progression in patients with acute lacunar infarction. MATERIALS AND METHODS The study comprised 60 patients with acute lacunar infarction. All enrolled subjects underwent autonomic function tests including the 30° head-up tilt test, Valsalva test, heart rate response to deep breathing, and sympathetic skin response. The primary endpoint is the neurological progression, and the secondary endpoint is the 3-month outcome. RESULTS Increased initial National Institute of Health stroke scale (NIHSS), decreased time to admission from onset, decreased rise of heart rate in the 30° head-up tilt test, abnormal blood pressure response in the Valsalva test, and decreased rise of systolic blood pressure in stage IV of the Valsalva test are associated with neurological progression of acute lacunar infarction; an abnormal blood pressure response in the Valsalva test is significant in logistic regression analysis of neurological progression. Advanced age, increased initial NIHSS and modified Rankin scale, decreased expiration/inspiration ratio of heart rate to deep breathing, decreased rise of systolic blood pressure in stage IV of the Valsalva test, and neurological progression were associated with an unfavorable 3-month outcome; neurological progression was significant in logistic regression analysis of 3-month outcome. CONCLUSIONS An abnormal blood pressure change in the Valsalva test is associated with neurological progression in patients with acute lacunar infarction, and neurological progression can induce an unfavorable 3-month outcome.
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Affiliation(s)
- S. Y. Ha
- Department of Neurology; Haeundae-Paik Hospital; College of Medicine; Inje University; Busan Korea
| | - K. M. Park
- Department of Neurology; Haeundae-Paik Hospital; College of Medicine; Inje University; Busan Korea
| | - J. Park
- Department of Neurology; Haeundae-Paik Hospital; College of Medicine; Inje University; Busan Korea
| | - S. E. Kim
- Department of Neurology; Haeundae-Paik Hospital; College of Medicine; Inje University; Busan Korea
| | - B. I. Lee
- Department of Neurology; Haeundae-Paik Hospital; College of Medicine; Inje University; Busan Korea
| | - K. J. Shin
- Department of Neurology; Haeundae-Paik Hospital; College of Medicine; Inje University; Busan Korea
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Wells R, Spurrier AJ, Linz D, Gallagher C, Mahajan R, Sanders P, Page A, Lau DH. Postural tachycardia syndrome: current perspectives. Vasc Health Risk Manag 2017; 14:1-11. [PMID: 29343965 PMCID: PMC5749569 DOI: 10.2147/vhrm.s127393] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Postural tachycardia syndrome (POTS) is the combination of an exaggerated heart rate response to standing, in association with symptoms of lightheadedness or pre-syncope that improve when recumbent. The condition is often associated with fatigue and brain fog, resulting in significant disruptions at a critical time of diagnosis in adolescence and young adulthood. The heterogeneity of the underlying pathophysiology and the variable response to therapeutic interventions make management of this condition challenging for both patients and physicians alike. Here, we aim to review the factors and mechanisms that may contribute to the symptoms and signs of POTS and to present our perspectives on the clinical approach toward the diagnosis and management of this complex syndrome.
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Affiliation(s)
- Rachel Wells
- Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, University of Adelaide and Departments of Cardiology and Medicine, Royal Adelaide Hospital.,Department of Medicine, Royal Adelaide Hospital
| | | | - Dominik Linz
- Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, University of Adelaide and Departments of Cardiology and Medicine, Royal Adelaide Hospital
| | - Celine Gallagher
- Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, University of Adelaide and Departments of Cardiology and Medicine, Royal Adelaide Hospital
| | - Rajiv Mahajan
- Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, University of Adelaide and Departments of Cardiology and Medicine, Royal Adelaide Hospital
| | - Prashanthan Sanders
- Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, University of Adelaide and Departments of Cardiology and Medicine, Royal Adelaide Hospital
| | - Amanda Page
- Centre for Nutrition and Gastrointestinal Diseases, University of Adelaide, Adelaide, SA, Australia
| | - Dennis H Lau
- Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, University of Adelaide and Departments of Cardiology and Medicine, Royal Adelaide Hospital
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14
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Serrador JM, Freeman R. Enhanced Cholinergic Activity Improves Cerebral Blood Flow during Orthostatic Stress. Front Neurol 2017; 8:103. [PMID: 28373858 PMCID: PMC5357636 DOI: 10.3389/fneur.2017.00103] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 03/02/2017] [Indexed: 02/05/2023] Open
Abstract
Cerebral blood flow (CBF) and consequently orthostatic tolerance when upright depends on dilation of the cerebral vasculature in the face of reduced perfusion pressure associated with the hydrostatic gradient. However, it is still unclear if cholinergic activation plays a role in this dilation. To determine if enhancing central cholinergic activity with the centrally acting acetylcholinesterase inhibitor, physostigmine would increase CBF when upright compared to the peripherally acting acetylcholinesterase inhibitor, neostigmine, or saline. We performed a randomized double-blind dose-ranging study that took place over 3 days in a hospital-based research lab. Eight healthy controls (six women and two men, mean age, 26 years; range 21–33) were given infusions of physostigmine, neostigmine, or saline on three different days. Five-minute tilts were repeated at baseline (no infusion), Dose 1 (0.2 μg/kg/min physostigmine; 0.1 μg/kg/min neostigmine) and Dose 2 (0.6 μg/kg/min physostigmine or 0.3 μg/kg/min neostigmine), and placebo (0.9% NaCl). Cerebral blood velocity, beat-to-beat blood pressure, and end-tidal CO2 were continuously measured during tilts. Physostigmine (0.6 μg/kg/min) resulted in higher cerebral blood velocity during tilt (90.5 ± 1.5%) than the equivalent neostigmine (85.5 ± 2.6%) or saline (84.8 ± 1.7%) trials (P < 0.05). This increase occurred despite a greater postural hypocapnia, suggesting physostigmine had a direct vasodilatory effect on the cerebral vasculature. Cerebral hypoperfusion induced by repeated tilts was eliminated by infusion of physostigmine not neostigmine. In conclusion, this study provides the first evidence that enhancement of central, not peripheral, cholinergic activity attenuates the physiological decrease in CBF seen during upright tilt. These data support the need for further research to determine if enhancing central cholinergic activity may improve symptoms in patients with symptomatic orthostatic intolerance.
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Affiliation(s)
- Jorge M Serrador
- Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical Health Sciences, Newark, NJ, USA; Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; Cardiovascular Electronics, National University of Ireland Galway, Galway, Ireland
| | - Roy Freeman
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School , Boston, MA , USA
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Medow MS, Del Pozzi AT, Messer ZR, Terilli C, Stewart JM. Altered oscillatory cerebral blood flow velocity and autoregulation in postural tachycardia syndrome. Front Physiol 2014; 5:234. [PMID: 25002851 PMCID: PMC4067089 DOI: 10.3389/fphys.2014.00234] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/03/2014] [Indexed: 11/13/2022] Open
Abstract
Decreased upright cerebral blood flow (CBF) with hyperpnea and hypocapnia is seen in a minority of patients with postural tachycardia syndrome (POTS). More often, CBF is not decreased despite upright neurocognitive dysfunction. This may result from time-dependent changes in CBF. We hypothesized that increased oscillations in CBF occurs in POTS (N = 12) compared to healthy controls (N = 9), and tested by measuring CBF velocity (CBFv) by transcranial Doppler ultrasound of the middle cerebral artery, mean arterial pressure (MAP) and related parameters, supine and during 70° upright tilt. Autospectra for mean CBFv and MAP, and transfer function analysis were obtained over the frequency range of 0.0078-0.4 Hz. Upright HR was increased in POTS (125 ± 8 vs. 86 ± 2 bpm), as was diastolic BP (74 ± 3 vs. 65 ± 3 mmHg) compared to control, while peripheral resistance, cardiac output, and mean CBFv increased similarly with tilt. Upright BP variability (BPV), low frequency (LF) power (0.04-0.13 Hz), and peak frequency of BPV were increased in POTS (24.3 ± 4.1, and 18.4 ± 4.1 mmHg(2)/Hz at 0.091 Hz vs. 11.8 ± 3.3, and 8.8 ± 2 mmHg(2)/Hz c at 0.071 Hz), as was upright overall CBFv variability, low frequency power and peak frequency of CBFv variability (29.3 ± 4.7, and 22.1 ± 2.7 [cm/s](2)/Hz at.092 Hz vs. 14.7 ± 2.6, and 6.7 ± 1.2 [cm/s](2)/Hz at 0.077Hz). Autospectra were sharply peaked in POTS. LF phase was decreased in POTS (-14 ± 4 vs. -25 ± 10 degrees) while upright. LF gain was increased (1.51 ± 0.09 vs. 0.86 ± 0.12 [cm/s]/ mmHg) while coherence was increased (0.96 ± 0.01 vs. 0.80 ± 0.04). Increased oscillatory BP in upright POTS patients is closely coupled to oscillatory CBFv over a narrow bandwidth corresponding to the Mayer wave frequency. Therefore combined increased oscillatory BP and increased LF gain markedly increases CBFv oscillations in a narrow bandwidth. This close coupling of CBF to MAP indicates impaired cerebral autoregulation that may underlie upright neurocognitive dysfunction in POTS.
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Affiliation(s)
- Marvin S Medow
- Departments of Pediatrics, The Center for Hypotension, New York Medical College Valhalla, NY, USA ; Departments of Physiology, New York Medical College Valhalla, NY, USA
| | - Andrew T Del Pozzi
- Departments of Pediatrics, The Center for Hypotension, New York Medical College Valhalla, NY, USA
| | - Zachary R Messer
- Departments of Pediatrics, The Center for Hypotension, New York Medical College Valhalla, NY, USA
| | - Courtney Terilli
- Departments of Pediatrics, The Center for Hypotension, New York Medical College Valhalla, NY, USA
| | - Julian M Stewart
- Departments of Pediatrics, The Center for Hypotension, New York Medical College Valhalla, NY, USA ; Departments of Physiology, New York Medical College Valhalla, NY, USA
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16
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Mar PL, Raj SR. Neuronal and hormonal perturbations in postural tachycardia syndrome. Front Physiol 2014; 5:220. [PMID: 24982638 PMCID: PMC4059278 DOI: 10.3389/fphys.2014.00220] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 05/26/2014] [Indexed: 11/13/2022] Open
Abstract
The Postural Tachycardia Syndrome (POTS) is the most common disorder seen in autonomic clinics. Cardinal hemodynamic feature of this chronic and debilitating disorder of orthostatic tolerance is an exaggerated orthostatic tachycardia (≥30 bpm increase in HR with standing) in the absence of orthostatic hypotension. There are multiple pathophysiological mechanisms that underlie POTS. Some patients with POTS have evidence of elevated sympathoneural tone. This hyperadrenergic state is likely a driver of the excessive orthostatic tachycardia. Another common pathophysiological mechanism in POTS is a hypovolemic state. Many POTS patients with a hypovolemic state have been found to have a perturbed renin-angiotensin-aldosterone profile. These include inappropriately low plasma renin activity and aldosterone levels with resultant inadequate renal sodium retention. Some POTS patients have also been found to have elevated plasma angiotensin II (Ang-II) levels, with some studies suggesting problems with decreased angiotensin converting enzyme 2 activity and decreased Ang-II degradation. An understanding of these pathophysiological mechanisms in POTS may lead to more rational treatment approaches that derive from these pathophysiological mechanisms.
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Affiliation(s)
- Philip L Mar
- Departments of Medicine and Pharmacology, Vanderbilt University School of Medicine Nashville, TN, USA
| | - Satish R Raj
- Departments of Medicine and Pharmacology, Vanderbilt University School of Medicine Nashville, TN, USA
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17
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Del Pozzi AT, Pandey A, Medow MS, Messer ZR, Stewart JM. Blunted cerebral blood flow velocity in response to a nitric oxide donor in postural tachycardia syndrome. Am J Physiol Heart Circ Physiol 2014; 307:H397-404. [PMID: 24878770 DOI: 10.1152/ajpheart.00194.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cognitive deficits are characteristic of postural tachycardia syndrome (POTS). Intact nitrergic nitric oxide (NO) is important to cerebral blood flow (CBF) regulation, neurovascular coupling, and cognitive efficacy. POTS patients often experience defective NO-mediated vasodilation caused by oxidative stress. We have previously shown dilation of the middle cerebral artery in response to a bolus administration of the NO donor sodium nitroprusside (SNP) in healthy volunteers. In the present study, we hypothesized a blunted middle cerebral artery response to SNP in POTS. We used combined transcranial Doppler-ultrasound to measure CBF velocity and near-infrared spectroscopy to measure cerebral hemoglobin oxygenation while subjects were in the supine position. The responses of 17 POTS patients were compared with 12 healthy control subjects (age: 14-28 yr). CBF velocity in POTS patients and control subjects were not different at baseline (75 ± 3 vs. 71 ± 2 cm/s, P = 0.31) and decreased to a lesser degree with SNP in POTS patients (to 71 ± 3 vs. 62 ± 2 cm/s, P = 0.02). Changes in total and oxygenated hemoglobin (8.83 ± 0.45 and 8.13 ± 0.48 μmol/kg tissue) were markedly reduced in POTS patients compared with control subjects (14.2 ± 1.4 and 13.6 ± 1.6 μmol/kg tissue), primarily due to increased venous efflux. The data indicate reduced cerebral oxygenation, blunting of cerebral arterial vasodilation, and heightened cerebral venodilation. We conclude, based on the present study outcomes, that decreased bioavailability of NO is apparent in the vascular beds, resulting in a downregulation of NO receptor sites, ultimately leading to blunted responses to exogenous NO.
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Affiliation(s)
- Andrew T Del Pozzi
- Departments of Pediatrics and Physiology, New York Medical College, Center for Hypotension, Hawthorne, New York
| | - Akash Pandey
- Departments of Pediatrics and Physiology, New York Medical College, Center for Hypotension, Hawthorne, New York
| | - Marvin S Medow
- Departments of Pediatrics and Physiology, New York Medical College, Center for Hypotension, Hawthorne, New York
| | - Zachary R Messer
- Departments of Pediatrics and Physiology, New York Medical College, Center for Hypotension, Hawthorne, New York
| | - Julian M Stewart
- Departments of Pediatrics and Physiology, New York Medical College, Center for Hypotension, Hawthorne, New York
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18
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Loughan AR, Hertza J, Perna R. The Neuropsychological Profile of Postural Orthostatic Tachycardia Syndrome: Sibling Case Study. APPLIED NEUROPSYCHOLOGY. ADULT 2013; 20:306-312. [PMID: 30567046 DOI: 10.1080/09084282.2012.753075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Postural orthostatic tachycardia syndrome (POTS), estimated to affect 500,000 people in the United States alone, is a growing source of impairment and disability. Symptoms often consist of physical, cognitive, and psychological impairment. The symptoms are driven by fluctuations in cerebral blood flow. Cerebral perfusion is tightly controlled and linked to brain function as changes in posture can result in quick hemovascular regulation by the autonomic nervous system. Any delay in hemoregulation and cerebral blood flow can result in neurological symptoms. POTS is associated with chronic autonomic dysregulation, and people with POTS suffer differing degrees of cerebral hypoperfusion causing variability in symptoms. This article reviews the cases of two siblings (22 years old and 19 years old) who both suffer from POTS. They suffered physical symptoms along with difficulty organizing thoughts, sustaining attention, thinking quickly, multitasking, and recalling recent information, as well as depression and anxiety. These sisters have Full-Scale IQs (FSIQ) above average, yet they received academic accommodations and have ongoing cognitive dysfunction that prevents them from furthering their true potential. These cases illustrate the need for neuropsychologists and other treating providers to understand POTS, the related pathophysiology, and how cognitively debilitating POTS can be, even in the context of intact and high FSIQ scores.
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Affiliation(s)
- Ashlee R Loughan
- a Behavioral Medicine Department , Walton Rehabilitation Hospital , Augusta , Georgia
| | - Jeremy Hertza
- a Behavioral Medicine Department , Walton Rehabilitation Hospital , Augusta , Georgia
| | - Robert Perna
- a Behavioral Medicine Department , Walton Rehabilitation Hospital , Augusta , Georgia
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19
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Shanks L, Jason LA, Evans M, Brown A. Cognitive impairments associated with CFS and POTS. Front Physiol 2013; 4:113. [PMID: 23720636 PMCID: PMC3655280 DOI: 10.3389/fphys.2013.00113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 04/30/2013] [Indexed: 11/13/2022] Open
Abstract
Chronic fatigue syndrome (CFS) is characterized by fatigue, sleep dysfunction, and cognitive deficits (Fukuda et al., 1994). Research surrounding cognitive functioning among patients with CFS has found difficulty with memory, attention, and information processing. A similar disorder, postural tachycardia syndrome (POTS), is characterized by increased heart rate, fatigue, and mental cloudiness (Raj et al., 2009). Potential implications of cognitive deficits for patients with CFS and/or POTS are discussed, including difficulties with school and/or employment. A few biological theories (i.e., kindling, impairments in the central nervous system, and difficulty with blood flow) have emerged as potential explanations for the cognitive deficits reported in both CFS and POTS Future research should continue to examine possible explanations for cognitive impairments in CFS and POTS, and ultimately use this information to try and reduce cognitive impairments for these patients.
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Affiliation(s)
- Lindzi Shanks
- Center for Community Research, DePaul University Chicago, IL, USA
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20
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Ocon AJ. Caught in the thickness of brain fog: exploring the cognitive symptoms of Chronic Fatigue Syndrome. Front Physiol 2013; 4:63. [PMID: 23576989 PMCID: PMC3617392 DOI: 10.3389/fphys.2013.00063] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 03/15/2013] [Indexed: 11/13/2022] Open
Abstract
Chronic Fatigue Syndrome (CFS) is defined as greater than 6 months of persistent fatigue that is experienced physically and cognitively. The cognitive symptoms are generally thought to be a mild cognitive impairment, but individuals with CFS subjectively describe them as "brain fog." The impairment is not fully understood and often is described as slow thinking, difficulty focusing, confusion, lack of concentration, forgetfulness, or a haziness in thought processes. Causes of "brain fog" and mild cognitive impairment have been investigated. Possible physiological correlates may be due to the effects of chronic orthostatic intolerance (OI) in the form of the Postural Tachycardia Syndrome (POTS) and decreases in cerebral blood flow (CBF). In addition, fMRI studies suggest that individuals with CFS may require increased cortical and subcortical brain activation to complete difficult mental tasks. Furthermore, neurocognitive testing in CFS has demonstrated deficits in speed and efficiency of information processing, attention, concentration, and working memory. The cognitive impairments are then perceived as an exaggerated mental fatigue. As a whole, this is experienced by those with CFS as "brain fog" and may be viewed as the interaction of physiological, cognitive, and perceptual factors. Thus, the cognitive symptoms of CFS may be due to altered CBF activation and regulation that are exacerbated by a stressor, such as orthostasis or a difficult mental task, resulting in the decreased ability to readily process information, which is then perceived as fatiguing and experienced as "brain fog." Future research looks to further explore these interactions, how they produce cognitive impairments, and explain the perception of "brain fog" from a mechanistic standpoint.
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Affiliation(s)
- Anthony J Ocon
- Departments of Physiology/Medicine, Center for Hypotension, New York Medical College Valhalla, NY, USA
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Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome. Clin Sci (Lond) 2012; 122:227-38. [PMID: 21919887 DOI: 10.1042/cs20110241] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CFS (chronic fatigue syndrome) is commonly co-morbid with POTS (postural tachycardia syndrome). Individuals with CFS/POTS experience unrelenting fatigue, tachycardia during orthostatic stress and ill-defined neurocognitive impairment, often described as 'mental fog'. We hypothesized that orthostatic stress causes neurocognitive impairment in CFS/POTS related to decreased CBFV (cerebral blood flow velocity). A total of 16 CFS/POTS and 20 control subjects underwent graded tilt table testing (at 0, 15, 30, 45, 60 and 75°) with continuous cardiovascular, cerebrovascular, and respiratory monitoring and neurocognitive testing using an n-back task at each angle. The n-back task tests working memory, concentration, attention and information processing. The n-back task imposes increasing cognitive challenge with escalating (0-, 1-, 2-, 3- and 4-back) difficulty levels. Subject dropout due to orthostatic presyncope at each angle was similar between groups. There were no n-back accuracy or RT (reaction time) differences between groups while supine. CFS/POTS subjects responded less correctly during the n-back task test and had greater nRT (normalized RT) at 45, 60 and 75°. Furthermore, at 75° CFS/POTS subjects responded less correctly and had greater nRT than controls during the 2-, 3- and 4-back tests. Changes in CBFV were not different between the groups and were not associated with n-back task test scores. Thus we conclude that increasing orthostatic stress combined with a cognitive challenge impairs the neurocognitive abilities of working memory, accuracy and information processing in CFS/POTS, but that this is not related to changes in CBFV. Individuals with CFS/POTS should be aware that orthostatic stress may impair their neurocognitive abilities.
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23
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Canova D, Roatta S, Bosone D, Micieli G. Inconsistent detection of changes in cerebral blood volume by near infrared spectroscopy in standard clinical tests. J Appl Physiol (1985) 2011; 110:1646-55. [PMID: 21474700 DOI: 10.1152/japplphysiol.00003.2011] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The attractive possibility of near infrared spectroscopy (NIRS) to noninvasively assess cerebral blood volume and oxygenation is challenged by the possible interference from extracranial tissues. However, to what extent this may affect cerebral NIRS monitoring during standard clinical tests is ignored. To address this issue, 29 healthy subjects underwent a randomized sequence of three maneuvers that differently affect intra- and extracranial circulation: Valsalva maneuver (VM), hyperventilation (HV), and head-up tilt (HUT). Putative intracranial ("i") and extracranial ("e") NIRS signals were collected from the forehead and from the cheek, respectively, and acquired together with cutaneous plethysmography at the forehead (PPG), cerebral blood velocity from the middle cerebral artery, and arterial blood pressure. Extracranial contribution to cerebral NIRS monitoring was investigated by comparing Beer-Lambert (BL) and spatially resolved spectroscopy (SRS) blood volume indicators [the total hemoglobin concentration (tHb) and the total hemoglobin index, (THI)] and by correlating their changes with changes in extracranial circulation. While THIe and tHbe generally provided concordant indications, tHbi and THIi exhibited opposite-sign changes in a high percentage of cases (VM: 46%; HV: 31%; HUT: 40%). Moreover, tHbi was correlated with THIi only during HV (P < 0.05), not during VM and HUT, while it correlated with PPG in all three maneuvers (P < 0.01). These results evidence that extracranial circulation may markedly affect BL parameters in a high percentage of cases, even during standard clinical tests. Surface plethysmography at the forehead is suggested as complementary monitoring helpful in the interpretation of cerebral NIRS parameters.
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Affiliation(s)
- D Canova
- Neurovascular Laboratory, Istituto Di Ricovero e Cura a Carattere Scientifico, National Neurological Institute, C. Mondino Foundation, Pavia, [corrected] Italy.
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Fontenele JB, Félix FHC. Fibromyalgia and Related Medically Unexplained Symptoms: A Lost Link Between Cardiovascular and Nociception Modulation. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/10582450802679904] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ocon AJ, Medow MS, Taneja I, Clarke D, Stewart JM. Decreased upright cerebral blood flow and cerebral autoregulation in normocapnic postural tachycardia syndrome. Am J Physiol Heart Circ Physiol 2009; 297:H664-73. [PMID: 19502561 DOI: 10.1152/ajpheart.00138.2009] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Postural tachycardia syndrome (POTS), a chronic form of orthostatic intolerance, has signs and symptoms of lightheadedness, loss of vision, headache, fatigue, and neurocognitive deficits consistent with reductions in cerebrovascular perfusion. We hypothesized that young, normocapnic POTS patients exhibit abnormal cerebral autoregulation (CA) that results in decreased static and dynamic cerebral blood flow (CBF) autoregulation. All subjects had continuous recordings of mean arterial pressure (MAP) and CBF velocity (CBFV) using transcranial Doppler sonography in both the supine supine position and during a 70 degrees head-up tilt. During tilt, POTS patients (n = 9) demonstrated a higher heart rate than controls (n = 7) (109 +/- 6 vs. 80 +/- 2 beats/min, P < 0.05), whereas controls demonstrated a higher MAP than POTS (87 +/- 2 vs. 77 +/- 3 mmHg, P < 0.05). Also during tilt, mean CBFV decreased 19.5 +/- 2.6% in POTS patients versus 10.3 +/- 2.0% in controls (P < 0.05). We then used a transfer function analysis of MAP and CFBV in the frequency domain to quantify these changes. The low-frequency (LF; 0.04-0.15 Hz) component of CBFV variability increased during tilt in POTS patients (supine: 3 +/- 0.9 vs. tilt: 9 +/- 2, P < 0.02). In POTS patients, there was an increase in LF and high-frequency coherence between MAP and CBFV, an increase in LF gain, and a lack of significant change in phase. Static CA may be less effective in POTS patients compared with controls, since immediately after tilt CBFV decreased more in POTS patients and was highly oscillatory and autoregulation did not restore CBFV to baseline values until the subjects became supine. Dynamic CA may be less effective in POTS patients because MAP and CBFV during tilt became almost perfectly synchronous. We conclude that dynamic and static autoregulation of CBF are less effective in POTS patients compared with control subjects during orthostatic challenge.
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Affiliation(s)
- Anthony J Ocon
- Department of Physiology, The Center for Hypotension, New York Medical College, Valhalla, New York 10532, USA
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Freeman R, Kaufmann H. DISORDERS OF ORTHOSTATIC TOLERANCE-ORTHOSTATIC HYPOTENSION, POSTURAL TACHYCARDIA SYNDROME, AND SYNCOPE. Continuum (Minneap Minn) 2007. [DOI: 10.1212/01.con.0000299966.05395.6c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Stewart JM, Medow MS, Cherniack NS, Natelson BH. Postural hypocapnic hyperventilation is associated with enhanced peripheral vasoconstriction in postural tachycardia syndrome with normal supine blood flow. Am J Physiol Heart Circ Physiol 2006; 291:H904-13. [PMID: 16565300 PMCID: PMC4511478 DOI: 10.1152/ajpheart.01359.2005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous investigations have demonstrated a subset of postural tachycardia syndrome (POTS) patients characterized by normal peripheral resistance and blood volume while supine but thoracic hypovolemia and splanchnic blood pooling while upright secondary to splanchnic hyperemia. Such "normal-flow" POTS patients often demonstrate hypocapnia during orthostatic stress. We studied 20 POTS patients (14-23 yr of age) and compared them with 10 comparably aged healthy volunteers. We measured changes in heart rate, blood pressure, heart rate and blood pressure variability, arm and leg strain-gauge occlusion plethysmography, respiratory impedance plethysmography calibrated against pneumotachography, end-tidal partial pressure of carbon dioxide (Pet(CO2)), and impedance plethysmographic indexes of blood volume and blood flow within the thoracic, splanchnic, pelvic (upper leg), and lower leg regional circulations while supine and during upright tilt to 70 degrees. Ten POTS patients demonstrated significant hyperventilation and hypocapnia (POTS(HC)) while 10 were normocapnic with minimal increase in postural ventilation, comparable to control. While relative splanchnic hypervolemia and hyperemia occurred in both POTS groups compared with controls, marked enhancement in peripheral vasoconstriction occurred only in POTS(HC) and was related to thoracic blood flow. Variability indexes suggested enhanced sympathetic activation in POTS(HC) compared with other subjects. The data suggest enhanced cardiac and peripheral sympathetic excitation in POTS(HC).
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Affiliation(s)
- Julian M Stewart
- Department of Pediatrics, Research Division and Hypotension Laboratory, New York Medical College, Suite 3050, 19 Bradhurst Ave., Hawthorne, NY 10532, USA.
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