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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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2
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Stewart JM, Medow MS. Anticipatory central command on standing decreases cerebral blood velocity causing hypocapnia in hyperpneic postural tachycardia syndrome. J Appl Physiol (1985) 2023; 135:26-34. [PMID: 37227184 PMCID: PMC10281786 DOI: 10.1152/japplphysiol.00016.2023] [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: 01/10/2023] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 05/26/2023] Open
Abstract
Fifty percent of patients with postural tachycardia syndrome (POTS) are hypocapnic during orthostasis related to initial orthostatic hypotension (iOH). We determined whether iOH drives hypocapnia in POTS by low BP or decreased cerebral blood velocity (CBv). We studied three groups; healthy volunteers (n = 32, 18 ± 3 yr) were compared with POTS, grouped by presence [POTS-low end-tidal CO2 (↓ETCO2), n = 26, 19 ± 2 yr] or absence [POTS-normal upright end-tidal carbon dioxide (nlCO2), n = 28, 19 ± 3 yr] of standing hypocapnia defined by end-tidal CO2 (ETCO2) ≤ 30 mmHg at steady-state, measuring middle cerebral artery CBv, heart rate (HR), and beat-to-beat blood pressure (BP). After 30 min supine, subjects stood for 5 min. Quantities were measured prestanding, at minimum CBv, minimum BP, peak HR, CBv recovery, BP recovery, minimum HR, steady-state, and 5 min. Baroreflex gain was estimated by α index. iOH occurred with similar frequency and minimum BP in POTS-↓ETCO2 and POTS-nlCO2. Minimum CBv was reduced significantly (P < 0.05) in POTS-↓ETCO2 (48 ± 3 cm/s) preceding hypocapnia compared with POTS-nlCO2 (61 ± 3 cm/s) or Control (60 ± 2 cm/s). The anticipatory increased BP was significantly larger (P < 0.05) in POTS (8 ± 1 mmHg vs. 2 ± 1) and began ∼8 s prestanding. HR increased in all subjects, CBv increased significantly (P < 0.05) in both POTS-nlCO2 (76 ± 2 to 85 ± 2 cm/s) and Control (75 ± 2 to 80 ± 2 cm/s) consistent with central command. CBv decreased in POTS-↓ETCO2 (76 ± 3 to 64 ± 3 cm/s) correlating with decreased baroreflex gain. Cerebral conductance [meanCBv/mean arterial blood pressure (MAP)] was reduced in POTS-↓ETCO2 throughout. Data support the hypothesis that excessively reduced CBv during iOH may intermittently reduce carotid body blood flow, sensitizing that organ and producing postural hyperventilation in POTS-↓ETCO2. Excessive fall in CBv occurs in part during prestanding central command and is a facet of defective parasympathetic regulation in POTS.NEW & NOTEWORTHY Dyspnea is frequent in postural tachycardia syndrome (POTS) and is associated with upright hyperpnea and hypocapnia that drives sinus tachycardia. It is initiated by an exaggerated reduction in cerebral conductance and decreased cerebral blood flow (CBF) that precedes the act of standing. This is a form of autonomically mediated "central command." Cerebral blood flow is further reduced by initial orthostatic hypotension common in POTS. Hypocapnia is maintained during the standing response and might account for persistent postural tachycardia.
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Affiliation(s)
- Julian M Stewart
- Department of Pediatrics, New York Medical College, Valhalla, New York, United States
- Department of Physiology, New York Medical College, Valhalla, New York, United States
| | - Marvin S Medow
- Department of Pediatrics, New York Medical College, Valhalla, New York, United States
- Department of Physiology, New York Medical College, Valhalla, New York, United States
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3
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Incognito AV, Baker J, Li O, Ranada SI. Thinking from the heart: Arrhythmia‐induced reduction in cerebral blood flow and the cumulative burden on cognitive function in cardiovascular disease. J Physiol 2022; 600:4255-4258. [DOI: 10.1113/jp283651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 08/24/2022] [Indexed: 11/08/2022] Open
Affiliation(s)
- Anthony V. Incognito
- Department of Physiology and Pharmacology Cumming School of Medicine University of Calgary Calgary AB Canada
| | - Jacquie Baker
- Libin Cardiovascular Institute Department of Cardiac Sciences Cumming School of Medicine University of Calgary Calgary AB Canada
| | - Olivia Li
- Department of Physiology and Pharmacology Cumming School of Medicine University of Calgary Calgary AB Canada
| | - Shaun I. Ranada
- Libin Cardiovascular Institute Department of Cardiac Sciences Cumming School of Medicine University of Calgary Calgary AB Canada
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4
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Hollingsworth C, Boyette V, Rich EM, Vas A. Cognition and Postural Tachycardia Syndrome (POTS): Participant-Identified Challenges and Strategies, and Implications for Intervention. Occup Ther Health Care 2022; 36:220-236. [PMID: 34802375 DOI: 10.1080/07380577.2021.2004485] [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: 12/01/2020] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
Postural Orthostatic Tachycardia Syndrome (POTS) is a condition that affects the autonomic nervous system and can cause both orthostatic and non-orthostatic physical and cognitive symptoms. The goal of this study is to gain meaningful understanding of the cognitive impact of POTS on daily function and to record the strategies participants use to overcome the challenges to help direct occupational therapy treatment. Results show daily function is greatly and negatively impacted by cognitive symptoms resulting from POTS. Participants have discovered strategies and used adaptations to enable them to participate in their daily and meaningful tasks. Using the experiences of those who live with POTS every day to guide interventions, occupational therapy practitioners can better understand and help to improve the autonomy and independence of the clients they treat.
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Affiliation(s)
| | - Valerie Boyette
- School of Occupational Therapy, Texas Woman's University, Dallas, TX, USA
| | - Emily M Rich
- School of Occupational Therapy, Texas Woman's University, Dallas, TX, USA
| | - Asha Vas
- School of Occupational Therapy, Texas Woman's University, Dallas, TX, USA
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5
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Ray JC, Pham X, Foster E, Cheema S, Corcoran SJ, Matharu MS, Hutton EJ. The prevalence of headache disorders in Postural Tachycardia Syndrome: A systematic review and meta-analysis of the literature. Cephalalgia 2022; 42:1274-1287. [PMID: 35469447 DOI: 10.1177/03331024221095153] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Headache is a common presentation of postural tachycardia syndrome, yet robust prevalence data is lacking. OBJECTIVES To undertake a systematic review and meta-analysis to estimate the prevalence of headache disorders in postural tachycardia syndrome, and to explore the potential shared pathophysiological mechanisms that underpin these conditions as well as treatment options. METHODS Three databases were searched for publications evaluating prevalence of migraine (primary outcome) and general and orthostatic headache (secondary outcomes) in patients with postural tachycardia syndrome. Two independent reviewers selected studies and extracted data. A random-effects meta-analysis calculated the pooled prevalence of migraine in postural tachycardia syndrome. A narrative literature review explored the pathophysiology and treatment options for concurrent headache disorders and postural tachycardia syndrome. RESULTS Twenty-three articles met inclusion criteria. Estimated pooled prevalence of migraine in postural tachycardia syndrome was 36.8% (95% CI 2.9-70.7%). Various shared pathophysiological pathways for these conditions, as well as proposed treatment strategies, were identified.Limitations: Heterogeneity of study design, populations, and methodology for identifying headache disorders and postural tachycardia syndrome limited the generalisability of results. CONCLUSIONS Migraine is a commonly reported comorbidity in POTS, however the true prevalence cannot be determined from the current literature. Further studies are required to assess this comorbidity and investigate the underlying mechanisms, as well as identify effective treatment strategies.
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Affiliation(s)
- Jason C Ray
- Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia.,Department of Neuroscience, Monash University, Melbourne, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
| | - Xiuxian Pham
- Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia
| | - Emma Foster
- Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia.,Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
| | - Sanjay Cheema
- Headache and Facial Pain Group, University College London Queen Square Institute of Neurology, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Susan J Corcoran
- Department of Cardiology, Alfred Hospital, Melbourne Victoria, Australia
| | - Manjit S Matharu
- Headache and Facial Pain Group, University College London Queen Square Institute of Neurology, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Elspeth J Hutton
- Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia.,Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
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6
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Stock JM, Chelimsky G, Edwards DG, Farquhar WB. Dietary sodium and health: How much is too much for those with orthostatic disorders? Auton Neurosci 2022; 238:102947. [PMID: 35131651 PMCID: PMC9296699 DOI: 10.1016/j.autneu.2022.102947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 11/09/2021] [Accepted: 01/16/2022] [Indexed: 10/19/2022]
Abstract
High dietary salt (NaCl) increases blood pressure (BP) and can adversely impact multiple target organs including the vasculature, heart, kidneys, brain, autonomic nervous system, skin, eyes, and bone. However, patients with orthostatic disorders are told to increase their NaCl intake to help alleviate symptoms. While there is evidence to support the short-term benefits of increasing NaCl intake in these patients, there are few studies assessing the benefits and side effects of long-term high dietary NaCl. The evidence reviewed suggests that high NaCl can adversely impact multiple target organs, often independent of BP. However, few of these studies have been performed in patients with orthostatic disorders. We conclude that the recommendation to increase dietary NaCl in patients with orthostatic disorders should be done with care, keeping in mind the adverse impact on dietary NaCl in people without orthostatic disorders. Modest, rather than robust, increases in NaCl intake may be sufficient to alleviate symptoms but also minimize any long-term negative effects.
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Affiliation(s)
- Joseph M Stock
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Gisela Chelimsky
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - David G Edwards
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - William B Farquhar
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America.
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7
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Owens AP, Mathias CJ, Iodice V. Autonomic Dysfunction in Autism Spectrum Disorder. Front Integr Neurosci 2022; 15:787037. [PMID: 35035353 PMCID: PMC8756818 DOI: 10.3389/fnint.2021.787037] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/29/2021] [Indexed: 11/13/2022] Open
Abstract
Background: There have been previous reports of enhanced sympathoexcitation in autism spectrum disorder (ASD). However, there has been no formal investigation of autonomic dysfunction in ASD. Also, the joint hypermobile form of Ehlers-Danlos syndrome (hE-DS) that maybe overrepresented in ASD and orthostatic related autonomic dysfunction. This study examined the comorbidity of ASD, autonomic dysfunction and hE-DS in two UK autonomic national referral centers. Proven, documented and globally accepted clinical autonomic investigations were used to assess neuro-cardiovascular autonomic function in a cohort of ASD subjects and in age-matched healthy controls. Methods: Clinical data from 28 referrals with a confirmed diagnosis of ASD over a 10-year period were compared with 19 age-matched healthy controls. Autonomic function was determined using methods established in the centers previously described in detail. Results: 20/28 ASD had a diagnosed autonomic condition; 9 had the postural tachycardia syndrome (PoTS), 4 PoTS and vasovagal syncope (VVS), 3 experienced presyncope, 1 essential hyperhidrosis, 1 orthostatic hypotension, 1 VVS alone and 1 a combination of PoTS, VVS and essential hyperhidrosis. 16/20 ASD with autonomic dysfunction had hE-DS. In ASD, basal heart rate and responses to orthostatic tests of autonomic function were elevated, supporting previous findings of increased sympathoexcitation. However, sympathetic vasoconstriction was impaired in ASD. Conclusion: Intermittent neuro-cardiovascular autonomic dysfunction affecting heart rate and blood pressure was over-represented in ASD. There is a strong association with hE-DS. Autonomic dysfunction may further impair quality of life in ASD, particularly in those unable to adequately express their experience of autonomic symptoms.
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Affiliation(s)
- Andrew P Owens
- Department of Old Age Psychiatry, King's College London, Institute of Psychiatry, Psychology and Neuroscience, London, United Kingdom
| | - Christopher J Mathias
- Autonomic Unit, National Hospital Neurology and Neurosurgery, UCLH NHS Trust, London, United Kingdom.,UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.,Neurovascular Medicine Unit, Lindo Wing, St Mary's Hospital, Imperial College NHS Healthcare Trust, London, United Kingdom
| | - Valeria Iodice
- Autonomic Unit, National Hospital Neurology and Neurosurgery, UCLH NHS Trust, London, United Kingdom.,UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
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8
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van Campen C(LMC, Rowe PC, Visser FC. Orthostatic Symptoms and Reductions in Cerebral Blood Flow in Long-Haul COVID-19 Patients: Similarities with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. MEDICINA (KAUNAS, LITHUANIA) 2021; 58:medicina58010028. [PMID: 35056336 PMCID: PMC8778312 DOI: 10.3390/medicina58010028] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/18/2021] [Accepted: 12/21/2021] [Indexed: 12/12/2022]
Abstract
Background and Objectives: Symptoms and hemodynamic findings during orthostatic stress have been reported in both long-haul COVID-19 and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), but little work has directly compared patients from these two groups. To investigate the overlap in these clinical phenotypes, we compared orthostatic symptoms in daily life and during head-up tilt, heart rate and blood pressure responses to tilt, and reductions in cerebral blood flow in response to orthostatic stress in long-haul COVID-19 patients, ME/CFS controls, and healthy controls. Materials and Methods: We compared 10 consecutive long-haul COVID-19 cases with 20 age- and gender-matched ME/CFS controls with postural tachycardia syndrome (POTS) during head-up tilt, 20 age- and gender-matched ME/CFS controls with a normal heart rate and blood pressure response to head-up tilt, and 10 age- and gender-matched healthy controls. Identical symptom questionnaires and tilt test procedures were used for all groups, including measurement of cerebral blood flow and cardiac index during the orthostatic stress. Results: There were no significant differences in ME/CFS symptom prevalence between the long-haul COVID-19 patients and the ME/CFS patients. All long-haul COVID-19 patients developed POTS during tilt. Cerebral blood flow and cardiac index were more significantly reduced in the three patient groups compared with the healthy controls. Cardiac index reduction was not different between the three patient groups. The cerebral blood flow reduction was larger in the long-haul COVID-19 patients compared with the ME/CFS patients with a normal heart rate and blood pressure response. Conclusions: The symptoms of long-haul COVID-19 are similar to those of ME/CFS patients, as is the response to tilt testing. Cerebral blood flow and cardiac index reductions during tilt were more severely impaired than in many patients with ME/CFS. The finding of early-onset orthostatic intolerance symptoms, and the high pre-illness physical activity level of the long-haul COVID-19 patients, makes it unlikely that POTS in this group is due to deconditioning. These data suggest that similar to SARS-CoV-1, SARS-CoV-2 infection acts as a trigger for the development of ME/CFS.
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Affiliation(s)
| | - Peter C. Rowe
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA;
| | - Frans C. Visser
- Stichting CardioZorg, Planetenweg 5, 2132 HN Hoofddorp, The Netherlands;
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9
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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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10
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van Campen C(LMC, Rowe PC, Visser FC. Reductions in Cerebral Blood Flow Can Be Provoked by Sitting in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients. Healthcare (Basel) 2020; 8:healthcare8040394. [PMID: 33050553 PMCID: PMC7712289 DOI: 10.3390/healthcare8040394] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/06/2020] [Accepted: 10/09/2020] [Indexed: 12/11/2022] Open
Abstract
Introduction: In a large study with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) patients, we showed that 86% had symptoms of orthostatic intolerance in daily life and that 90% had an abnormal reduction in cerebral blood flow (CBF) during a standard tilt test. A standard head-up tilt test might not be tolerated by the most severely affected bed-ridden ME/CFS patients. Sitting upright is a milder orthostatic stress. The present study examined whether a sitting test, measuring cerebral blood flow by extracranial Doppler, would be sufficient to provoke abnormal reductions in cerebral blood flow in severe ME/CFS patients. Methods and results: 100 severe ME/CFS patients were studied, (88 females) and were compared with 15 healthy controls (HC) (13 females). CBF was measured first while seated for at least one hour, followed by a CBF measurement in the supine position. Fibromyalgia was present in 37 patients. Demographic data as well as supine heart rate and blood pressures were not different between ME/CFS patients and HC. Heart rate and blood pressure did not change significantly between supine and sitting both in patients and HC. Supine CBF was not different between patients and HC. In contrast, absolute CBF during sitting was lower in patients compared to HC: 474 (96) mL/min in patients and 627 (89) mL/min in HC; p < 0.0001. As a result, percent CBF reduction while seated was −24.5 (9.4)% in severe ME/CFS patients and −0.4 (1.2)% in HC (p < 0.0001). In the ten patients who had no orthostatic intolerance complaints in daily life, the CBF reduction was −2.7 (2.1)%, which was not significantly different from HC (p = 0.58). The remaining 90 patients with orthostatic intolerance complaints had a −26.9 (6.2)% CBF reduction. No difference in CBF parameters was found in patients with and without fibromyalgia. Patients with a previous diagnosis of postural orthostatic tachycardia syndrome (POTS) had a significantly larger CBF reduction compared with those without POTS: 28.8 (7.2)% vs. 22.3 (9.7)% (p = 0.0008). Conclusions: A sitting test in severe ME/CFS patients was sufficient to provoke a clinically and statistically significant mean CBF decline of 24.5%. Patients with a previous diagnosis of POTS had a larger CBF reduction while seated, compared to patients without POTS. The magnitude of these CBF reductions is similar to the results in less severely affected ME/CFS patients during head-up tilt, suggesting that a sitting test is adequate for the diagnosis of orthostatic intolerance in severely affected patients.
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Affiliation(s)
- C (Linda) MC van Campen
- Stichting CardioZorg, 2132 HN Hoofddorp, The Netherlands;
- Correspondence: ; Tel.: +0031-208934125
| | - Peter C. Rowe
- Department of Paediatrics, John Hopkins University School of Medicine, Baltimore, MD 21205, USA;
| | - Frans C Visser
- Stichting CardioZorg, 2132 HN Hoofddorp, The Netherlands;
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11
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Stewart JM, Kota A, O'Donnell-Smith MB, Visintainer P, Terilli C, Medow MS. The preponderance of initial orthostatic hypotension in postural tachycardia syndrome. J Appl Physiol (1985) 2020; 129:459-466. [PMID: 32702262 DOI: 10.1152/japplphysiol.00540.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Reduced systolic/diastolic blood pressure (BP) by >40/20 mmHg defines initial orthostatic hypotension (IOH). Rapid resolution of hypotension and lightheadedness follows, but tachycardia may be prolonged. We aimed to examine IOH in controls and patients with postural tachycardia syndrome (POTS) using indices of spontaneous fluctuations of heart rate (HR) and systolic BP as measures of cardiac baroreflex differences. We recruited otherwise healthy IOH patients without POTS (n = 20, 16 ± 3 yr), healthy volunteers (n = 32, 17 ± 3 yr), and POTS patients (n = 39, 17 ± 4 yr). Subjects were instrumented for electrocardiography and beat-to-beat BP. After 10 min supine, subjects stood for 5 min. Following supine recovery, subjects underwent 70° head-up tilt for 10 min to test for POTS. BP, HR, and time, referenced to standing, were measured at events during standing: minimum BP, BP recovery, peak HR, HR minimum, and steady state. Baseline HR and BP were higher in POTS compared with healthy groups. IOH occurred in 13% of controls and 51% of POTS patients. The BP minimum was lower in POTS. Parasympathetic modulation of cardiac baroreflex was decreased in all POTS and control-IOH subjects. Sympathetic indices were increased. Events following BP minimum occurred progressively later in all POTS and control-IOH subjects compared with non-IOH controls. IOH is more frequent in POTS than in controls with a lower minimum BP. POTS has markedly reduced heart rate variability and baroreflex, indicating reduced HR buffering of BP. POTS-IOH and control-IOH subjects had similar peak HR despite decreased minimum BP in POTS. IOH data indicate modest parasympathetic and cardiovagal baroreflex deficits in control-IOH subjects. Parasympathetic deficits are more severe in all POTS patients.NEW & NOTEWORTHY Significant initial orthostatic hypotension (IOH) occurs in ~50% of postural tachycardia syndrome (POTS) patients and 13% of controls. Heart rate and blood pressure recovery are prolonged in IOH sustaining lightheadedness; IOH is more prevalent and severe in POTS. Altered cerebral blood flow and cardiorespiratory regulation are more prevalent in POTS. Altered heart rate variability and baroreflex gain may cause nearly instantaneous lightheadedness in POTS. IOH alone fails to confer a strong probability of POTS.
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Affiliation(s)
- Julian M Stewart
- Department of Pediatric, New York Medical College, Valhalla, New York.,Department of Physiology, New York Medical College, Valhalla, New York
| | - Archana Kota
- Department of Pediatric, New York Medical College, Valhalla, New York
| | | | - Paul Visintainer
- Baystate Medical Center, University of Massachusetts School of Medicine, Springfield, Massachusetts
| | - Courtney Terilli
- Department of Pediatric, New York Medical College, Valhalla, New York
| | - Marvin S Medow
- Department of Pediatric, New York Medical College, Valhalla, New York.,Department of Physiology, New York Medical College, Valhalla, New York
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12
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Smith EC, Diedrich A, Raj SR, Gamboa A, Shibao CA, Black BK, Peltier A, Paranjape SY, Biaggioni I, Okamoto LE. Splanchnic Venous Compression Enhances the Effects of ß-Blockade in the Treatment of Postural Tachycardia Syndrome. J Am Heart Assoc 2020; 9:e016196. [PMID: 32673517 PMCID: PMC7660715 DOI: 10.1161/jaha.120.016196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Background Splanchnic venous pooling induced by upright posture triggers a compensatory increase in heart rate (HR), a response that is exaggerated in patients with postural tachycardia syndrome. To assess whether abdominal compression attenuates orthostatic tachycardia and improves symptoms, 18 postural tachycardia syndrome patients (32±2 years) were randomized to receive either abdominal compression (40 mm Hg applied with an inflatable binder ≈2 minutes before standing) or propranolol (20 mg) in a placebo‐controlled, crossover study. Methods and Results Systolic blood pressure, HR, and symptoms were assessed while seated and standing, before and 2 hours postdrug. As expected, propranolol decreased standing HR compared with placebo (81±2 versus 98±4 beats per minute; P<0.001) and was associated with lower standing systolic blood pressure (93±2 versus 100±2 mm Hg for placebo; P=0.002). Compression had no effect on standing HR (96±4 beats per minute) but increased standing systolic blood pressure compared with placebo and propranolol (106±2 mm Hg; P<0.01). Neither propranolol nor compression improved symptoms compared with placebo. In 16 patients we compared the combination of abdominal compression and propranolol with propranolol alone. The combination had no additional effect on standing HR (81±2 beats per minute for both interventions) but prevented the decrease in standing systolic blood pressure produced by propranolol (98±2 versus 93±2 mm Hg for propranolol; P=0.029), and significantly improved total symptom burden (−6±2 versus −1±2 for propranolol; P=0.041). Conclusions Splanchnic venous compression alone did not improve HR or symptoms but prevented the blood pressure decrease produced by propranolol. The combination was more effective in improving symptoms than either alone. Splanchnic venous compression can be a useful adjuvant therapy to propranolol in postural tachycardia syndrome. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00262470.
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Affiliation(s)
- Emily C Smith
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN
| | - André Diedrich
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN.,Department of Biomedical Engineering Vanderbilt University School of Medicine Nashville TN
| | - Satish R Raj
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN.,Department of Cardiac Sciences Libin Cardiovascular Institute of Alberta University of Calgary Canada
| | - Alfredo Gamboa
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN
| | - Cyndya A Shibao
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN
| | - Bonnie K Black
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN
| | - Amanda Peltier
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Vanderbilt Heart and Vascular Institute Vanderbilt University School of Medicine Nashville TN.,Department of Neurology Vanderbilt University School of Medicine Nashville TN
| | - Sachin Y Paranjape
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN
| | - Italo Biaggioni
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN.,Department of Pharmacology Vanderbilt University School of Medicine Nashville TN
| | - Luis E Okamoto
- Vanderbilt Autonomic Dysfunction Center Vanderbilt University School of Medicine Nashville TN.,Division of Clinical Pharmacology Vanderbilt University School of Medicine Nashville TN.,Department of Medicine Vanderbilt University School of Medicine Nashville TN
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13
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Maksoud R, du Preez S, Eaton-Fitch N, Thapaliya K, Barnden L, Cabanas H, Staines D, Marshall-Gradisnik S. A systematic review of neurological impairments in myalgic encephalomyelitis/ chronic fatigue syndrome using neuroimaging techniques. PLoS One 2020; 15:e0232475. [PMID: 32353033 PMCID: PMC7192498 DOI: 10.1371/journal.pone.0232475] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 04/15/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Myalgic encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS) is a multi-system illness characterised by a diverse range of debilitating symptoms including autonomic and cognitive dysfunction. The pathomechanism remains elusive, however, neurological and cognitive aberrations are consistently described. This systematic review is the first to collect and appraise the literature related to the structural and functional neurological changes in ME/CFS patients as measured by neuroimaging techniques and to investigate how these changes may influence onset, symptom presentation and severity of the illness. METHODS A systematic search of databases Pubmed, Embase, MEDLINE (via EBSCOhost) and Web of Science (via Clarivate Analytics) was performed for articles dating between December 1994 and August 2019. Included publications report on neurological differences in ME/CFS patients compared with healthy controls identified using neuroimaging techniques such as magnetic resonance imaging, positron emission tomography and electroencephalography. Article selection was further refined based on specific inclusion and exclusion criteria. A quality assessment of included publications was completed using the Joanna Briggs Institute checklist. RESULTS A total of 55 studies were included in this review. All papers assessed neurological or cognitive differences in adult ME/CFS patients compared with healthy controls using neuroimaging techniques. The outcomes from the articles include changes in gray and white matter volumes, cerebral blood flow, brain structure, sleep, EEG activity, functional connectivity and cognitive function. Secondary measures including symptom severity were also reported in most studies. CONCLUSIONS The results suggest widespread disruption of the autonomic nervous system network including morphological changes, white matter abnormalities and aberrations in functional connectivity. However, these findings are not consistent across studies and the origins of these anomalies remain unknown. Future studies are required confirm the potential neurological contribution to the pathology of ME/CFS.
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Affiliation(s)
- Rebekah Maksoud
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
- * E-mail:
| | - Stanley du Preez
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
- School of Medical Sciences, Griffith University, Gold Coast, Australia
- School of Medicine, Griffith University, Gold Coast, Australia
| | - Natalie Eaton-Fitch
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
- School of Medical Sciences, Griffith University, Gold Coast, Australia
| | - Kiran Thapaliya
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
| | - Leighton Barnden
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
| | - Hélène Cabanas
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
| | - Donald Staines
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
| | - Sonya Marshall-Gradisnik
- National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
- Consortium Health International for Myalgic Encephalomyelitis, Griffith University, Gold Coast, Australia
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14
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Medic Spahic J, Ricci F, Aung N, Hallengren E, Axelsson J, Hamrefors V, Melander O, Sutton R, Fedorowski A. Proteomic analysis reveals sex-specific biomarker signature in postural orthostatic tachycardia syndrome. BMC Cardiovasc Disord 2020; 20:190. [PMID: 32321428 PMCID: PMC7178975 DOI: 10.1186/s12872-020-01465-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 04/05/2020] [Indexed: 12/12/2022] Open
Abstract
Background Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular (CV) autonomic disorder of unknown etiology characterized by an excessive heart rate increase on standing and orthostatic intolerance. In this study we sought to identify novel CV biomarkers potentially implicated in POTS pathophysiology. Methods We conducted a nested case-control study within the Syncope Study of Unselected Population in Malmö (SYSTEMA) cohort including 396 patients (age range, 15–50 years) with either POTS (n = 113) or normal hemodynamic response during passive head-up-tilt test (n = 283). We used a targeted approach to explore changes in cardiovascular proteomics associated with POTS through a sequential two-stage process including supervised principal component analysis and univariate ANOVA with Bonferroni correction. Results POTS patients were younger (26 vs. 31 years; p < 0.001) and had lower BMI than controls. The discovery algorithm identified growth hormone (GH) and myoglobin (MB) as the most specific biomarker fingerprint for POTS. Plasma level of GH was higher (9.37 vs 8.37 of normalised protein expression units (NPX); p = 0.002), whereas MB was lower (4.86 vs 5.14 NPX; p = 0.002) in POTS compared with controls. In multivariate regression analysis, adjusted for age and BMI, and stratified by sex, lower MB level in men and higher GH level in women remained independently associated with POTS. Conclusions Cardiovascular proteomics analysis revealed sex-specific biomarker signature in POTS featured by higher plasma level of GH in women and lower plasma level of MB in men. These findings point to sex-specific immune-neuroendocrine dysregulation and deconditioning as potentially key pathophysiological traits underlying POTS.
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Affiliation(s)
- Jasmina Medic Spahic
- Department of Clinical Sciences, Malmö, Faculty of Medicine, Lund University, Clinical Research Center, 214 28, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, 214 28, Malmö, Sweden
| | - Fabrizio Ricci
- Department of Clinical Sciences, Malmö, Faculty of Medicine, Lund University, Clinical Research Center, 214 28, Malmö, Sweden.,Department of Neuroscience, Imaging and Clinical Sciences, "G. d'Annunzio" University, 66100, Chieti, Italy.,Casa di Cura Villa Serena, Città Sant'Angelo, 65013, Pescara, Italy
| | - Nay Aung
- William Harvey Research Institute, NIHR Cardiovascular Biomedical Research Unit at Barts, Queen Mary University of London, London, UK
| | - Erik Hallengren
- Department of Clinical Sciences, Malmö, Faculty of Medicine, Lund University, Clinical Research Center, 214 28, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, 214 28, Malmö, Sweden
| | - Jonas Axelsson
- Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Viktor Hamrefors
- Department of Clinical Sciences, Malmö, Faculty of Medicine, Lund University, Clinical Research Center, 214 28, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, 214 28, Malmö, Sweden
| | - Olle Melander
- Department of Clinical Sciences, Malmö, Faculty of Medicine, Lund University, Clinical Research Center, 214 28, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, 214 28, Malmö, Sweden
| | - Richard Sutton
- National Heart and Lung Institute, Imperial College, Hammersmith Hospital Campus, Ducane Road, W12 0NN, London, UK
| | - Artur Fedorowski
- Department of Clinical Sciences, Malmö, Faculty of Medicine, Lund University, Clinical Research Center, 214 28, Malmö, Sweden. .,Department of Cardiology, Skåne University Hospital, Carl-Bertil Laurells gata 9, 214 28, Malmö, Sweden.
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15
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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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16
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Swai J, Hu Z, Zhao X, Rugambwa T, Ming G. Heart rate and heart rate variability comparison between postural orthostatic tachycardia syndrome versus healthy participants; a systematic review and meta-analysis. BMC Cardiovasc Disord 2019; 19:320. [PMID: 31888497 PMCID: PMC6936126 DOI: 10.1186/s12872-019-01298-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/05/2019] [Indexed: 12/20/2022] Open
Abstract
Background A number of published literature has reported that, physiologically, heart rate variability (HRV) in patients with postural orthostatic tachycardia syndrome (POTS) to be greatly confounded by age, sex, race, physical fitness, and circadian rhythm. The purpose of this study was to compare between POTS patients versus healthy participants, in terms of heart rate (HR) and HRV after Head-Up tilt test (HUTT), by systematic review and meta-analysis of available published literature. Methods MEDLINE (using PubMed interphase), EMBASE and SCOPUS were systematically searched for observational studies comparing POTS patients versus healthy patients, in terms of HR and HRV. HRV was grouped into Time and frequency domain outcome measurements. The time domain was measured as mean RR- interval and mean the square root of the mean of squares of successive R-R waves (rMSSD) in milliseconds. The frequency domain was measured as mean values of Low frequency power (LF), High frequency power (HF), LF/HF-ratio, LF-normalized units (LF(n.u)) and HF-normalized units (HF(n.u)). Demographic data, comorbidities, and mean values of HR, RR- interval, rMSSD, LF, HF, LF/HF-ratio, LF-(n.u) and H.F-n.u were extracted from each group and compared, by their mean differences as an overall outcome measure. Computer software, RevMan 5.3 was utilized, at a 95% significance level. Results Twenty (20) eligible studies were found to report 717 POTS and 641 healthy participants. POTS group had a higher mean HR (p < 0.05), lower mean RR-Interval (p < 0.05), lower rMSSD (p < 0.05) than healthy participants. Furthermore, POTS group had lower mean HF(p > 0.05), lower mean LF(p > 0.05), and lower mean HF(n.u) (p > 0.05), higher LF/HF-Ratio (p > 0.05) and higher LF(n.u) (p > 0.05) as compared to healthy participants. Conclusion POTS patients have a higher HR than healthy patients after HUTT and lower HRV in terms of time domain measure but not in terms of frequency domain measure. HR and time domain analyses of HRV are more reliable than frequency domain analysis in differentiating POTS patients from the healthy participants. We call upon sensitivity and specificity studies.
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Affiliation(s)
- Joel Swai
- Department of Internal medicine, Benjamin Mkapa Hospital, Dodoma city, Tanzania. .,Department of Nephrology and Rheumatology, Xiangya Third Hospital, Central South University, Changsha city, Hunan, People's Republic of China.
| | - Zixuan Hu
- Department of Gastroenterology, Xiangya Third Hospital, Central South University, Changsha city, Hunan, People's Republic of China
| | - Xiexiong Zhao
- Department of Cardiology, Xiangya Third Hospital, Central South University, Changsha city, Hunan, People's Republic of China
| | - Tibera Rugambwa
- Department of Obstetrics and Gynecology, Mbeya Zonal Referral Hospital, Mbeya city, Tanzania
| | - Gui Ming
- Department of Nephrology and Rheumatology, Xiangya Third Hospital, Central South University, Changsha city, Hunan, People's Republic of China
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17
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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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18
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Tsai Owens M, Harbeck-Weber C, Kirsch A, Sim L, Zaccariello M, Homan K, Fischer P. Neurocognitive Difficulties Among Youth with POTS within an Intensive Pain Rehabilitation Program. J Pediatr Psychol 2019; 44:567-575. [PMID: 30649432 DOI: 10.1093/jpepsy/jsy106] [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] [Received: 06/15/2018] [Revised: 11/22/2018] [Accepted: 12/02/2018] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE Adolescents and young adults (AYAs) with postural orthostatic tachycardia syndrome (POTS) commonly report cognitive difficulties, though there is limited information regarding the objective measurement of neurocognitive deficits in this population. This study described the rates of subjectively experienced and objectively measured neurocognitive difficulties and explored effects of medications on neurocognitive functioning among AYAs with POTS admitted to an intensive outpatient pain rehabilitation program. METHODS Participants in a pain rehabilitation program diagnosed with POTS (N = 96; ages 12-22) were included in the study. Medical characteristics, reported cognitive complaints, and neurocognitive assessment results were collected through retrospective medical record review. We calculated descriptive statistics and Pearson's χ2 or Fisher's exact tests, where appropriate. RESULTS While 96% of this sample reported subjective cognitive complaints, as a group, they performed in the Average range on standardized measures of intellectual functioning, attention, and memory. The majority did not demonstrate any normative (73%) or relative (54%) weaknesses in attention or memory. Those prescribed an antiepileptic (n = 19) were less likely to have visual-spatial memory weaknesses but more likely to have attention weaknesses. CONCLUSIONS Despite a high frequency of reported cognitive difficulties, most AYAs with POTS did not demonstrate neurocognitive impairment on standardized, one-on-one assessment. Suggestions for further study of biopsychosocial contributors to neurocognitive difficulties and for clinical use of neurocognitive assessments in this population were provided.
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19
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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: 7] [Impact Index Per Article: 1.4] [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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20
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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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21
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Hypocapnic cerebral hypoperfusion: A biomarker of orthostatic intolerance. PLoS One 2018; 13:e0204419. [PMID: 30256820 PMCID: PMC6157889 DOI: 10.1371/journal.pone.0204419] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 09/07/2018] [Indexed: 01/21/2023] Open
Abstract
The objective of the study was to identify markers of hypocapnic cerebral hypoperfusion (HYCH) in patients with orthostatic intolerance (OI) without tachycardia and without orthostatic hypotension. This single center, retrospective study included OI patients referred for autonomic evaluation with the 10 min tilt test. Heart rate, end-tidal CO2 (ET-CO2), blood pressure, and cerebral blood flow velocity (CBFv) from middle cerebral artery were monitored. HYCH was defined by: (1) Symptoms of OI; (2) Orthostatic hypocapnia (low ET-CO2); (3) Abnormal decline in orthostatic CBFv due to hypocapnia; 4) Absence of tachycardia, orthostatic hypotension, or other causes of low CBFv or hypocapnia. Sixteen subjects met HYCH criteria (15/1 women/men, age 38.5±8.0 years) and were matched by age and gender to postural tachycardia patients (POTS, n = 16) and healthy controls (n = 16). During the tilt, CBFv decreased more in HYCH (-22.4±7.7%, p<0.0001) and POTS (-19.0±10.3%, p<0.0001) compared to controls (-3.0±5.0%). Orthostatic ET-CO2 was lower in HYCH (26.4±4.2 (mmHg), p<0.0001) and POTS (28.6±4.3, p<0.0001) compared to controls (36.9 ± 2.1 mmHg). Orthostatic heart rate was normal in HYCH (89.0±10.9 (BPM), p<0.08) and controls (80.8 ±11.2), but was higher in POTS (123.7±11.2, p<0.0001). Blood pressure was normal and similar in all groups. It is concluded that both HYCH and POTS patients have comparable decrease in CBFv which is due to vasoconstrictive effect of hypocapnia. Blood flow velocity monitoring can provide an objective biomarker for HYCH in OI patients without tachycardia.
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Nagiub M, Moskowitz W, Fortunato J. Systematic literature review of pathophysiology of postural orthostatic tachycardia syndrome (angiotensin II receptor subtype imbalance theory). PROGRESS IN PEDIATRIC CARDIOLOGY 2018. [DOI: 10.1016/j.ppedcard.2018.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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van Campen CLMC, Verheugt FWA, Visser FC. Cerebral blood flow changes during tilt table testing in healthy volunteers, as assessed by Doppler imaging of the carotid and vertebral arteries. Clin Neurophysiol Pract 2018; 3:91-95. [PMID: 30215015 PMCID: PMC6133915 DOI: 10.1016/j.cnp.2018.02.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 02/17/2018] [Accepted: 02/20/2018] [Indexed: 01/13/2023] Open
Abstract
Extracranial cerebral artery Doppler imaging show CBF changes during tilt testing. Total CBF during tilt testing decreases 6% in healthy volunteers. Flow decrease of internal carotid and vertebral arteries during tilting is similar.
Objectives Using different techniques, reduction of cerebral blood flow (CBF) during orthostatic stress were demonstrated. One study reported flow reduction of the right internal carotid (ICA) and vertebral (VA) artery during orthostatic stress by Doppler imaging, with different effects on the 2 vessels. Global CBF changes, using this technique, have not been reported. Therefore, flow of the ICA, VA and global CBF were measured during head-up tilt testing. Methods 33 healthy volunteers underwent tilt testing. At three time points (supine, half way and at the end of the test) Doppler imaging of the ICA and VA was performed, as well as PetCO2 measurements. Results Global CBF was significantly reduced by 4.5 ± 2.8% halfway the test and by 6.0 ± 3.4% at the end. All 4 artery flows were significantly reduced during the tilt, without differences between them. Despite small changes in PetCO2 there was a significant relation between de CBF decrease and PetCO2 decrease (p < 0.05). Conclusions Orthostatic stress in HV results in a small but significant reduction of CBF by a homogenous reduction in the four cerebral vessels and is modulated by PetCO2 changes. Significance CBF changes can be measured during tilt testing using Doppler VA and ICA imaging.
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Affiliation(s)
| | - Freek W A Verheugt
- Radboud UMC, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
| | - Frans C Visser
- Stichting CardioZorg, Planetenweg 5, 2132 HN Hoofddorp, The Netherlands
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Ozturk ED, Tan CO. Human cerebrovascular function in health and disease: insights from integrative approaches. J Physiol Anthropol 2018; 37:4. [PMID: 29454381 PMCID: PMC5816507 DOI: 10.1186/s40101-018-0164-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/02/2018] [Indexed: 11/21/2022] Open
Abstract
Background The marked increase in the size of the brain, and consequently, in neural processing capability, throughout human evolution is the basis of the higher cognitive function in humans. However, greater neural, and thus information processing capability, comes at a significant metabolic cost; despite its relatively small size, the modern human brain consumes almost a quarter of the glucose and oxygen supply in the human body. Fortunately, several vascular mechanisms ensure sufficient delivery of glucose and oxygen to the active neural tissue (neurovascular coupling), prompt removal of neural metabolic by-products (cerebral vasoreactivity), and constant global blood supply despite daily variations in perfusion pressure (cerebral autoregulation). The aim of this review is to provide an integrated overview of the available data on these vascular mechanisms and their underlying physiology. We also briefly review modern experimental approaches to assess these mechanisms in humans, and further highlight the importance of these mechanisms for humans’ evolutionary success by providing examples of their healthy adaptations as well as pathophysiological alterations. Conclusions Data reviewed in this paper demonstrate the importance of the cerebrovascular function to support humans’ unique ability to form new and different interactions with each other and their surroundings. This highlights that there is much insight into the neural and cognitive functions that could be gleaned from interrogating the cerebrovascular function.
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Affiliation(s)
- Erin D Ozturk
- Cerebrovascular Research Laboratory, Spaulding Rehabilitation Hospital, Boston, MA, USA.,Department of Psychology, Harvard University, Cambridge, MA, USA
| | - Can Ozan Tan
- Cerebrovascular Research Laboratory, Spaulding Rehabilitation Hospital, Boston, MA, USA. .,Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, USA.
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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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Jahshan S, Dayan L, Jacob G. Nitric oxide-sensitive guanylyl cyclase signaling affects CO2-dependent but not pressure-dependent regulation of cerebral blood flow. Am J Physiol Regul Integr Comp Physiol 2017; 312:R948-R955. [DOI: 10.1152/ajpregu.00241.2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 01/06/2023]
Abstract
Cerebrovascular CO2 reactivity is affected by nitric oxide (NO). We tested the hypothesis that sildenafil selectively potentiates NO-cGMP signaling, which affects CO2 reactivity. Fourteen healthy males (34 ± 2 yr) were enrolled in the study. Blood pressure (BP), ECG, velocity of cerebral blood flow (CBF; measured by transcranial Doppler), and end-tidal CO2 (EtCO2) were assessed at baseline (CO2 ~39 mmHg), during hyperventilation (CO2 ~24 mmHg), during hypercapnia (CO2 ~46 mmHg), during boluses of phenylephrine (25–200 µg), and during graded head-up tilting (HUT). Measurements were repeated 1 h after 100 mg sildenafil were taken. Results showed that sildenafil did not affect resting BP, heart rate, CBF peak and mean velocities, estimated regional cerebrovascular resistance (eCVR; mean BP/mean CBF), breath/min, and EtCO2: 117 ± 2/67 ± 3 mmHg, 69 ± 3 beats/min, 84 ± 5 and 57 ± 4 cm/s, 1.56 ± 0.1 mmHg·cm−1·s−1, 14 ± 0.5 breaths/min, and 39 ± 0.9 mmHg, respectively. Sildenafil increased and decreased the hypercapnia induced in CBF and eCVR, respectively. Sildenafil also attenuated the decrease in peak velocity of CBF, 25 ± 2 vs. 20 ± 2% ( P < 0.05) and increased the eCVR, 2.5 ± 0.2 vs. 2 ± 0.2% ( P < 0.03) during hyperventilation. Sildenafil did not affect CBF despite significant increases in the eCVRs that were elicited by phenylephrine and HUT. This investigation suggests that sildenafil, which potentiates the NO-cGMP signaling, seems to affect the cerebrovascular CO2 reactivity without affecting the static and dynamic pressure-dependent mechanisms of cerebrovascular autoregulation.
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Affiliation(s)
- Shadi Jahshan
- J. Recanati Autonomic Dysfunction Center, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
- Neurosurgery Department, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel; and
| | - Lior Dayan
- J. Recanati Autonomic Dysfunction Center, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
| | - Giris Jacob
- Department of Internal Medicine, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
- J. Recanati Autonomic Dysfunction Center, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
- Faculty of Medicine, Tel Aviv “Sourasky” Medical Center, Tel Aviv University, Tel Aviv, Israel
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Shin KJ, Kim SE, Park KM, Park J, Ha SY, Kim SE, Kwon OY. Cerebral hemodynamics in orthostatic intolerance with normal head-up tilt test. Acta Neurol Scand 2016; 134:108-15. [PMID: 26427910 DOI: 10.1111/ane.12516] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2015] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS) are well-known causes of orthostatic intolerance (OI). In addition, there are OI patients who are characterized by the symptoms of OI and lack of abnormal findings in head-up tilt (HUT) test. The aim of this study was to determine the cerebral hemodynamic changes in HUT test of OI patients with normal HUT (OINH). MATERIALS AND METHODS Two hundred and sixty-one OI patients and 50 healthy controls were enrolled in this study. All subjects underwent transcranial Doppler test while performing the HUT test. Forty-five patients had OH, 33 patients had POTS, and 183 patients had OINH. Blood pressures, heart rate, cerebral blood flow velocities (CBFVs), end-tidal carbon dioxide (ET-PCO2 ), cerebral critical closing pressure (CCP), cerebral perfusion pressure (CPP), and cerebral vascular resistance (CVR) were measured during HUT test. We compared the hemodynamic parameters of OINH with those of OH, POTS, and healthy controls. RESULTS Reduced CBFVs, CPP, and ET-PCO2 and elevated CCP were observed in the HUT test of all four groups. CVR was reduced in three OI patients. The drops in systolic CBFV, CPP, and CVR of OINH patients were greater than those of healthy controls. The changes in parameters in the HUT test of OINH group were not different from those of OH and POTS groups except prominent decrements of CPP and CVR in OH group. CONCLUSION Our findings suggest that OINH is true OI sharing the common pathomechanism of OH and POTS.
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Affiliation(s)
- K. J. Shin
- Department of Neurology; Haeundae Paik Hospital; Inje University; Busan South Korea
| | - S. E. Kim
- Department of Neurology; Haeundae Paik Hospital; Inje University; Busan South Korea
| | - K. M. Park
- Department of Neurology; Haeundae Paik Hospital; Inje University; Busan South Korea
| | - J. Park
- Department of Neurology; Haeundae Paik Hospital; Inje University; Busan South Korea
| | - S. Y. Ha
- Department of Neurology; Haeundae Paik Hospital; Inje University; Busan South Korea
| | - S. E. Kim
- Department of Neurology; Haeundae Paik Hospital; Inje University; Busan South Korea
| | - O.-Y. Kwon
- Department of Neurology; School of Medicine; Gyeongsang National University; Jinju South Korea
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De Wandele I, Rombaut L, De Backer T, Peersman W, Da Silva H, De Mits S, De Paepe A, Calders P, Malfait F. Orthostatic intolerance and fatigue in the hypermobility type of Ehlers-Danlos Syndrome. Rheumatology (Oxford) 2016; 55:1412-20. [DOI: 10.1093/rheumatology/kew032] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Indexed: 01/26/2023] Open
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A novel method for assessing cerebral autoregulation in preterm infants using transfer function analysis. Pediatr Res 2016; 79:453-9. [PMID: 26571222 PMCID: PMC4821724 DOI: 10.1038/pr.2015.238] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 09/11/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND Autoregulatory dysfunction is an important contributor to brain injury in premature infants, particularly intraventricular hemorrhage (IVH). The autoregulatory system acts as a filter that dampens the systemic blood flow to follow a normal cerebral perfusion profile. METHODS Simultaneous arterial blood pressure and cerebral near-infrared spectroscopy (NIRS) data were collected from infants born before 28 wk estimated gestational age. The resulting data were preprocessed and then divided into nonoverlapping 20-min epochs. The transfer function estimate was calculated to determine dampening ability. RESULTS Sixty-two infants were prospectively recruited with a mean estimated gestational age of 25.4 ± 1.3 wk and birth weight of 832 ± 199 g. 67% were male, 24/62 had IVH, 17/62 received dopamine, 47/62 had antenatal steroid exposure, and 22/62 received fentanyl.Advancing estimated gestational age and birth weight z-score predicted stronger dampening while African-American race and IVH of any grade predicted weaker dampening. CONCLUSION This preliminary report suggests an impairment in dampening ability associated with immaturity, decreased birth weight z-score, and African-American race. Decreased dampening is also associated with IVH, although these results cannot distinguish between decreased dampening as an antecedent or sequela of IVH. These observations should be studied in a larger sample.
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Abstract
OBJECTIVE Orthostatic dizziness without orthostatic hypotension is common but underlying pathophysiology is poorly understood. This study describes orthostatic cerebral hypoperfusion syndrome (OCHOs). OCHOs is defined by (1) abnormal orthostatic drop of cerebral blood flow velocity (CBFv) during the tilt test and (2) absence of orthostatic hypotension, arrhythmia, vascular abnormalities, or other causes of abnormal orthostatic CBFv. METHODS This retrospective study included patients referred for evaluation of unexplained orthostatic dizziness. Patients underwent standardized autonomic testing, including 10 min of tilt test. The following signals were monitored: heart rate, end tidal CO2, blood pressure, and CBFv from the middle cerebral artery using transcranial Doppler. Patients were screened for OCHOs. Patients who fulfilled the OCHOs criteria were compared to age- and gender-matched controls. RESULTS From 1279 screened patients, 102 patients (60/42 women/men, age 51.1 ± 14.9, range 19-84 years) fulfilled criteria of OCHOs. There was no difference in baseline supine hemodynamic variables between OCHOs and the control group. During the tilt, mean CBFv decreased 24.1 ± 8.2% in OCHOs versus 4.2 ± 5.6% in controls (p < 0.0001) without orthostatic hypotension in both groups. Supine mean blood pressure (OCHOs/controls, 90.5 ± 10.6/91.1 ± 9.4 mmHg, p = 0.62) remained unchanged during the tilt (90.4 ± 9.7/92.1 ± 9.6 mmHg, p = 0.2). End tidal CO2 and heart rate responses to the tilt were normal and equal in both groups. CONCLUSION OCHOs is a novel syndrome of low orthostatic CBFv. Two main pathophysiological mechanisms are proposed, including active cerebral vasoconstriction and passive increase of peripheral venous compliance. OCHOs may be a common cause of orthostatic dizziness.
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Affiliation(s)
- Peter Novak
- Department of Neurology, Brigham and Women's Faulkner Hospital, Harvard Medical School , Boston, MA , USA
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Vasileva D, Lubenova D, Mihova M, Grigorova-Petrova K, Dimitrova A. Errata Corrige. Orthostatic Reactivity in Patients with Ischemic Stroke in the Chronic Period. http://dx.doi.org/10.3889/oamjms.2015.090. Open Access Maced J Med Sci 2015; 3:531-6. [PMID: 27275283 PMCID: PMC4877852 DOI: 10.3889/oamjms.2015.095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 07/27/2015] [Accepted: 07/28/2015] [Indexed: 11/21/2022] Open
Abstract
AIM: This study aims to trace the influence of specialized kinesitherapeutic methodology (SKTM) on orthostatic reactivity in patients with ischemic stroke in the chronic period (ISChP). MATERIAL AND METHODS: An active orthostatic test is used for the evaluation of the orthostatic reactions. The arterial blood pressure and heart rate were defined in the 10 minutes of supine position, before and after 1, 5 and 10 minutes of active upright position. The orthostatic autoregulation is evaluated four times - at the beginning of the study, on the 10th day, on the 1st month and three months after the start of the KT. The classification by Thulesius was used to separate the patients into two groups depending on the type of their orthostatic reactivity. RESULTS: At the beginning of the study of infringements symptomatic type orthostatic reactivity (SOR) was observed in 24 patients and hypertensive type orthostatic reactivity (HOR) was observed in the remaining 32 patients. Once applied SKTM establish improvement of orthostatic autoregulation for the groups SOR and HOR at the 10th day and the 1st month with a level of significance p <0.05. CONCLUSION: The applied specialized kinesitherapeutic methodology continued later as an adapted exercise program at home, has significantly improved the orthostatic reactivity in patients with orthostatic dysregulation due to the ISChP.
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Affiliation(s)
- Danche Vasileva
- University "Goce Delchev", Faculty of Medical Sciences, Shtip, Republic of Macedonia
| | - Daniela Lubenova
- National Sports Academy, Physical Therapy and Rehabilitation, Sofia, Bulgaria
| | - Marija Mihova
- Ss Cyril and Methodius University of Skopje, Faculty of Computer Sciences and Engineering, Skopje, Republic of Macedonia
| | | | - Antoaneta Dimitrova
- National Sports Academy, Physical Therapy and Rehabilitation, Sofia, Bulgaria
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Vasileva D, Lubenova D, Mihova M, Grigorova-Petrova K, Dimitrova A. Orthostatic Reactivity in Patients with Ischemic Stroke in the Chronic Period. Open Access Maced J Med Sci 2015; 3:397-402. [PMID: 27275257 PMCID: PMC4877826 DOI: 10.3889/oamjms.2015.090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 07/27/2015] [Accepted: 07/28/2015] [Indexed: 11/21/2022] Open
Abstract
AIM: This study aims to trace the influence of specialized kinesitherapeutic methodology (SKTM) on orthostatic reactivity in patients with ischemic stroke in the chronic period (ISChP). MATERIAL AND METHODS: An active orthostatic test is used for the evaluation of the orthostatic reactions. The arterial blood pressure and heart rate were defined in the 10 minutes of supine position, before and after 1, 5 and 10 minutes of active upright position. The orthostatic autoregulation is evaluated four times - at the beginning of the study, on the 10th day, on the 1st month and three months after the start of the KT. The classification by Thulesius was used to separate the patients into two groups depending on the type of their orthostatic reactivity. RESULTS: At the beginning of the study of infringements symptomatic type orthostatic reactivity (SOR) was observed in 24 patients and hypertensive type orthostatic reactivity (HOR) was observed in the remaining 32 patients. Once applied SKTM establish improvement of orthostatic autoregulation for the groups SOR and HOR at the 10th day and the 1st month with a level of significance p <0.05. CONCLUSION: The applied specialized kinesitherapeutic methodology continued later as an adapted exercise program at home, has significantly improved the orthostatic reactivity in patients with orthostatic dysregulation due to the ISChP.
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Affiliation(s)
- Danche Vasileva
- University "Goce Delchev", Faculty of Medical Sciences, Shtip, Republic of Macedonia
| | - Daniela Lubenova
- National Sports Academy, Physical Therapy and Rehabilitation, Sofia, Bulgaria
| | - Marija Mihova
- Ss Cyril and Methodius University of Skopje, Faculty of Computer Sciences and Engineering, Skopje, Republic of Macedonia
| | | | - Antoaneta Dimitrova
- National Sports Academy, Physical Therapy and Rehabilitation, Sofia, Bulgaria
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Read MI, Harrison JC, Kerr DS, Sammut IA. Atenolol offers better protection than clonidine against cardiac injury in kainic acid-induced status epilepticus. Br J Pharmacol 2015; 172:4626-38. [PMID: 25765931 DOI: 10.1111/bph.13132] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Revised: 02/21/2015] [Accepted: 03/06/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Status epilepticus is increasingly associated with cardiac injury in both clinical and animal studies. The current study examined ECG activity for up to 48 h following kainic acid (KA) seizure induction and compared the potential of atenolol and clonidine to attenuate this cardiac pathology. EXPERIMENTAL APPROACH Sprague-Dawley rats (male, 300-350 g) were implanted with ECG and electrocorticogram electrodes to allow simultaneous telemetric recordings of cardiac and cortical responses during and after KA-induced seizures. Animals were randomized into saline controls, and saline vehicle-, clonidine- or atenolol-pretreated KA groups. KEY RESULTS KA administration in the saline-pretreated group produced an immediate bradycardic response (maximal decrease of 28 ± 6%), coinciding with low-level seizure activity. As high-level seizure behaviours and EEG spiking increased, tachycardia also developed, with a maximum heart rate increase of 38 ± 7% coinciding with QTc prolongation and T wave elevation. Both clonidine and atenolol pretreatment attenuated seizure activity and reduced KA-induced changes in heart rate, QTc interval and T wave amplitude observed during both bradycardic and tachycardic phases in saline-pretreated KA animals. Clonidine, however, failed to reduce the power of EEG frequencies. Atenolol and to a lesser extent clonidine attenuated the cardiac hypercontraction band necrosis, inflammatory infiltration, and oedema at 48 h after KA, relative to the saline-KA group. CONCLUSIONS AND IMPLICATIONS Severe seizure activity in this model was clearly associated with altered ECG activity and cardiac pathology. We suggest that modulation of sympathetic activity by atenolol provides a promising cardioprotective approach in status epilepticus.
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Affiliation(s)
- M I Read
- Department of Pharmacology, University of Otago School of Medical Sciences, Dunedin, New Zealand
| | - J C Harrison
- Department of Pharmacology, University of Otago School of Medical Sciences, Dunedin, New Zealand
| | - D S Kerr
- Department of Pharmacology, University of Otago School of Medical Sciences, Dunedin, New Zealand
| | - I A Sammut
- Department of Pharmacology, University of Otago School of Medical Sciences, Dunedin, New Zealand
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Lankford J, Numan M, Hashmi SS, Gourishankar A, Butler IJ. Cerebral blood flow during HUTT in young patients with orthostatic intolerance. Clin Auton Res 2015; 25:277-84. [PMID: 26280217 DOI: 10.1007/s10286-015-0295-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 04/15/2015] [Indexed: 11/29/2022]
Abstract
PURPOSE To investigate patterns of change in cerebral perfusion during head-up tilt testing (HUTT) in children and young adults with autonomic dysfunction. METHODS We utilized near-infrared spectroscopy (NIRS) to estimate bilateral cerebral perfusion patterns during HUTT in 71 adolescents and young adults with a diagnosis of autonomic dysfunction. In addition, we used transthoracic impedance to measure cardiac stroke volume and thus infer autonomic tone, heart rate, and blood pressure during the test. Cerebral blood-flow wave-patterns were then visually analyzed and associated with clinical symptoms and measures of cardiovascular and autonomic function. RESULTS Visual analysis of contour changes in head NIRS values during phases of HUTT revealed variable patterns of cerebral blood flow, some specifically associated with severe symptomatology (i.e., syncope). We also observed an inequality in blood flow of the cerebral hemispheres in many patients. Finally, we observed changes in cardiac stroke volume during HUTT, as previously reported, that related to changes in head NIRS. CONCLUSION These results confirm a decrease in cerebral blood flow during HUTT as assessed by head NIRS in patients with autonomic dysfunction. Specifically, we have profiled the cerebral blood flow contours throughout the phases of HUTT, which add insight into the clinical spectrum of the disorder and may correlate with clinical severity.
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Affiliation(s)
- Jeremy Lankford
- Division of Child and Adolescent Neurology, Department of Pediatrics, The University of Texas at Houston Medical School, 6410 Fannin Street, Suite 732, Houston, TX, 77030, USA.
| | - Mohammed Numan
- Division of Pediatric Cardiology, Department of Pediatrics, The University of Texas at Houston Medical School, 6410 Fannin Street, Suite 360, Houston, TX, 77030, USA
| | - S Shahrukh Hashmi
- Department of Pediatrics, Pediatric Research Center, The University of Texas at Houston Medical School, 6431 Fannin Street, MSB 3.020, Houston, TX, 77030, USA
| | - Anand Gourishankar
- Division of General Pediatrics, Department of Pediatrics, The University of Texas at Houston Medical School, 6431 Fannin Street, MSB 3.020, Houston, TX, 77030, USA
| | - Ian J Butler
- Division of Child and Adolescent Neurology, Department of Pediatrics, The University of Texas at Houston Medical School, 6410 Fannin Street, Suite 732, Houston, TX, 77030, USA
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Abdulla A, Rajeevan T. Reversible postural orthostatic tachycardia syndrome. World J Clin Cases 2015; 3:655-660. [PMID: 26244158 PMCID: PMC4517341 DOI: 10.12998/wjcc.v3.i7.655] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 09/30/2014] [Accepted: 04/14/2015] [Indexed: 02/05/2023] Open
Abstract
Postural orthostatic tachycardia syndrome (POTS) is a relatively rare syndrome recognised since 1940. It is a heterogenous condition with orthostatic intolerance due to dysautonomia and is characterised by rise in heart rate above 30 bpm from base line or to more than 120 bpm within 5-10 min of standing with or without change in blood pressure which returns to base line on resuming supine position. This condition present with various disabling symptoms such as light headedness, near syncope, fatigue, nausea, vomiting, tremor, palpitations and mental clouding, etc. However there are no identifiable signs on clinical examination and patients are often diagnosed to have anxiety disorder. The condition predominantly affects young female between the ages of 15-50 but is rarely described in older people. We describe an older patient who developed POTS which recovered over 12 mo. Recognising this condition is important as there are treatment options available to alleviate the disabling symptoms.
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Eccles JA, Owens AP, Mathias CJ, Umeda S, Critchley HD. Neurovisceral phenotypes in the expression of psychiatric symptoms. Front Neurosci 2015; 9:4. [PMID: 25713509 PMCID: PMC4322642 DOI: 10.3389/fnins.2015.00004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 01/05/2015] [Indexed: 12/01/2022] Open
Abstract
This review explores the proposal that vulnerability to psychological symptoms, particularly anxiety, originates in constitutional differences in the control of bodily state, exemplified by a set of conditions that include Joint Hypermobility, Postural Tachycardia Syndrome and Vasovagal Syncope. Research is revealing how brain-body mechanisms underlie individual differences in psychophysiological reactivity that can be important for predicting, stratifying and treating individuals with anxiety disorders and related conditions. One common constitutional difference is Joint Hypermobility, in which there is an increased range of joint movement as a result of a variant of collagen. Joint hypermobility is over-represented in people with anxiety, mood and neurodevelopmental disorders. It is also linked to stress-sensitive medical conditions such as irritable bowel syndrome, chronic fatigue syndrome and fibromyalgia. Structural differences in “emotional” brain regions are reported in hypermobile individuals, and many people with joint hypermobility manifest autonomic abnormalities, typically Postural Tachycardia Syndrome. Enhanced heart rate reactivity during postural change and as recently recognized factors causing vasodilatation (as noted post-prandially, post-exertion and with heat) is characteristic of Postural Tachycardia Syndrome, and there is a phenomenological overlap with anxiety disorders, which may be partially accounted for by exaggerated neural reactivity within ventromedial prefrontal cortex. People who experience Vasovagal Syncope, a heritable tendency to fainting induced by emotional challenges (and needle/blood phobia), are also more vulnerable to anxiety disorders. Neuroimaging implicates brainstem differences in vulnerability to faints, yet the structural integrity of the caudate nucleus appears important for the control of fainting frequency in relation to parasympathetic tone and anxiety. Together there is clinical and neuroanatomical evidence to show that common constitutional differences affecting autonomic responsivity are linked to psychiatric symptoms, notably anxiety.
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Affiliation(s)
- Jessica A Eccles
- Psychiatry, Brighton and Sussex Medical School Brighton, UK ; Sussex Partnership National Health Service Foundation Trust Brighton, UK
| | - Andrew P Owens
- National Hospital Neurology and Neurosurgery, UCL National Health Service Trust London, UK ; Institute of Neurology, University College London London, UK
| | - Christopher J Mathias
- National Hospital Neurology and Neurosurgery, UCL National Health Service Trust London, UK ; Institute of Neurology, University College London London, UK
| | - Satoshi Umeda
- National Hospital Neurology and Neurosurgery, UCL National Health Service Trust London, UK ; Department of Psychology, Keio University Tokyo, Japan
| | - Hugo D Critchley
- Psychiatry, Brighton and Sussex Medical School Brighton, UK ; Sussex Partnership National Health Service Foundation Trust Brighton, UK ; Sackler Centre for Consciousness Science, University of Sussex Falmer, UK
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Taneja I, So S, Stewart JM, Evans M, Jason LA. Prevalence and Severity of Symptoms in a Sample of African Americans and White Participants. JOURNAL OF CULTURAL DIVERSITY 2015; 22:50-58. [PMID: 26245010 PMCID: PMC4863697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
According to the Centers for Disease Control and Prevention (2013), African Americans have a substantially greater prevalence of a range of health conditions when compared to other racial or ethnic groups. Many of these conditions have been attributed to the historical and contemporary social and economic disparities faced by the African American community. While many health conditions occur at a higher rate in African Americans, it is unclear whether there are specific symptom clusters that may also be more prevalent in African Americans as a result of these disparities. Potential differences in symptomology have not been thoroughly examined between African Americans and White populations. The current study compares the prevalence and pain severity of symptoms among a sample of African Americans and White participants. Significant differences in symptom prevalence were found in disturbed sleep and reproductive areas. African Americans also experience more pain due to symptoms related to orthostatic intolerance. Implications of this finding are discussed.
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Jason LA, Zinn ML, Zinn MA. Myalgic Encephalomyelitis: Symptoms and Biomarkers. Curr Neuropharmacol 2015; 13:701-34. [PMID: 26411464 PMCID: PMC4761639 DOI: 10.2174/1570159x13666150928105725] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 04/09/2015] [Accepted: 07/14/2015] [Indexed: 01/01/2023] Open
Abstract
Myalgic Encephalomyelitis (ME) continues to cause significant morbidity worldwide with an estimated one million cases in the United States. Hurdles to establishing consensus to achieve accurate evaluation of patients with ME continue, fueled by poor agreement about case definitions, slow progress in development of standardized diagnostic approaches, and issues surrounding research priorities. Because there are other medical problems, such as early MS and Parkinson's Disease, which have some similar clinical presentations, it is critical to accurately diagnose ME to make a differential diagnosis. In this article, we explore and summarize advances in the physiological and neurological approaches to understanding, diagnosing, and treating ME. We identify key areas and approaches to elucidate the core and secondary symptom clusters in ME so as to provide some practical suggestions in evaluation of ME for clinicians and researchers. This review, therefore, represents a synthesis of key discussions in the literature, and has important implications for a better understanding of ME, its biological markers, and diagnostic criteria. There is a clear need for more longitudinal studies in this area with larger data sets, which correct for multiple testing.
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Affiliation(s)
- Leonard A. Jason
- Department of Psychology, Center for Community Research, DePaul University, Chicago, Illinois, United States
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Stewart JM, Del Pozzi AT, Pandey A, Messer ZR, Terilli C, Medow MS. Oscillatory cerebral blood flow is associated with impaired neurocognition and functional hyperemia in postural tachycardia syndrome during graded tilt. Hypertension 2014; 65:636-43. [PMID: 25510829 DOI: 10.1161/hypertensionaha.114.04576] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We hypothesize that upright cognitive impairment in patients with postural tachycardia syndrome (POTS) is caused by reduced cerebral blood flow (CBF). The CBF velocity (CBF(v)) measured by transcranial Doppler ultrasound decreased excessively during 70° tilt in a minority of patients with intermittent hyperpnea/hypocapnia. Incremental tilt showed no difference in mean CBF(v). But N-back memory tasking indicated progressive compromised memory, reduced functional hyperemia, and reduced neurovascular coupling. Orthostasis caused slow oscillations in CBF(v) linked to oscillations in arterial pressure in patients with POTS. We also hypothesize that oscillatory CBF(v) degrades neurovascular coupling. We performed 2-back testing when subjects were in supine position and during incremental tilts to 15°, 30°, 45°, and 60° in 11 patients with POTS and 9 controls. Oscillatory arterial pressure, oscillatory CBF(v), and neurovascular coupling were similar in supine position. The oscillatory arterial pressure increased by 31%, 45%, 67%, and 93% in patients with POTS during tilt and remained unchanged in the controls. Oscillatory CBF(v) increased by 61%, 82%, 161%, and 264% in patients with POTS during tilt and remained unchanged in the controls. Functional hyperemia decreased from 4.1% to 3.0%, 1.1%, 0.2%, and to 0.04% in patients with POTS, but it was unchanged at 4% in the controls. Percent correct N-back responses decreased from 78% to 33% in patients with POTS, whereas they remained at 89% in the controls. In patients with POTS, oscillatory CBF(v) was linearly correlated with functional hyperemia (r(2)=0.76). Increased oscillatory CBF is associated with reduced neurovascular coupling and diminished cognitive performance in patients with POTS.
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Affiliation(s)
- Julian M Stewart
- From the Departments of Pediatrics (J.M.S., A.T.D.P., A.P., Z.R.M., C.T., M.S.M.) and Physiology (J.M.S., M.S.M.), New York Medical College, Valhalla.
| | - Andrew T Del Pozzi
- From the Departments of Pediatrics (J.M.S., A.T.D.P., A.P., Z.R.M., C.T., M.S.M.) and Physiology (J.M.S., M.S.M.), New York Medical College, Valhalla
| | - Akash Pandey
- From the Departments of Pediatrics (J.M.S., A.T.D.P., A.P., Z.R.M., C.T., M.S.M.) and Physiology (J.M.S., M.S.M.), New York Medical College, Valhalla
| | - Zachary R Messer
- From the Departments of Pediatrics (J.M.S., A.T.D.P., A.P., Z.R.M., C.T., M.S.M.) and Physiology (J.M.S., M.S.M.), New York Medical College, Valhalla
| | - Courtney Terilli
- From the Departments of Pediatrics (J.M.S., A.T.D.P., A.P., Z.R.M., C.T., M.S.M.) and Physiology (J.M.S., M.S.M.), New York Medical College, Valhalla
| | - Marvin S Medow
- From the Departments of Pediatrics (J.M.S., A.T.D.P., A.P., Z.R.M., C.T., M.S.M.) and Physiology (J.M.S., M.S.M.), New York Medical College, Valhalla
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Lewis NCS, Bain AR, MacLeod DB, Wildfong KW, Smith KJ, Willie CK, Sanders ML, Numan T, Morrison SA, Foster GE, Stewart JM, Ainslie PN. Impact of hypocapnia and cerebral perfusion on orthostatic tolerance. J Physiol 2014; 592:5203-19. [PMID: 25217373 PMCID: PMC4262334 DOI: 10.1113/jphysiol.2014.280586] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 09/01/2014] [Indexed: 12/25/2022] Open
Abstract
We examined two novel hypotheses: (1) that orthostatic tolerance (OT) would be prolonged when hyperventilatory-induced hypocapnia (and hence cerebral hypoperfusion) was prevented; and (2) that pharmacological reductions in cerebral blood flow (CBF) at baseline would lower the 'CBF reserve', and ultimately reduce OT. In study 1 (n = 24; aged 25 ± 4 years) participants underwent progressive lower-body negative pressure (LBNP) until pre-syncope; end-tidal carbon dioxide (P ET , CO 2) was clamped at baseline levels (isocapnic trial) or uncontrolled. In study 2 (n = 10; aged 25 ± 4 years), CBF was pharmacologically reduced by administration of indomethacin (INDO; 1.2 mg kg(-1)) or unaltered (placebo) followed by LBNP to pre-syncope. Beat-by-beat measurements of middle cerebral artery blood flow velocity (MCAv; transcranial Doppler), heart rate (ECG), blood pressure (BP; Finometer) and end-tidal gases were obtained continuously. In a subset of subjects' arterial-to-jugular venous differences were obtained to examine the independent impact of hypocapnia or cerebral hypoperfusion (following INDO) on cerebral oxygen delivery and extraction. In study 1, during the isocapnic trial, P ET , CO 2 was successfully clamped at baseline levels at pre-syncope (38.3 ± 2.7 vs. 38.5 ± 2.5 mmHg respectively; P = 0.50). In the uncontrolled trial, P ET , CO 2 at pre-syncope was reduced by 10.9 ± 3.9 mmHg (P ≤ 0.001). Compared to the isocapnic trial, the decline in mean MCAv was 15 ± 4 cm s(-1) (35%; P ≤ 0.001) greater in the uncontrolled trial, yet the time to pre-syncope was comparable between trials (544 ± 130 vs. 572 ± 180 s; P = 0.30). In study 2, compared to placebo, INDO reduced resting MCAv by 19 ± 4 cm s(-1) (31%; P ≤ 0.001), but time to pre-syncope remained similar between trials (placebo: 1123 ± 138 s vs. INDO: 1175 ± 212 s; P = 0.53). The brain extracted more oxygen in face of hypocapnia (34% to 53%) or cerebral hypoperfusion (34% to 57%) to compensate for reductions in delivery. In summary, cerebral hypoperfusion either at rest or induced by hypocapnia at pre-syncope does not impact OT, probably due to a compensatory increase in oxygen extraction.
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Affiliation(s)
- Nia C S Lewis
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
| | - Anthony R Bain
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
| | - David B MacLeod
- Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
| | - Kevin W Wildfong
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
| | - Kurt J Smith
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
| | - Christopher K Willie
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
| | | | - Tianne Numan
- MIRA, University of Twente, Enschede, The Netherlands
| | - Shawnda A Morrison
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada Jozef Stefan Institute, Ljubljana, Slovenia
| | - Glen E Foster
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
| | | | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, University of British Columbia, Okanagan, Canada
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Medow MS, Sood S, Messer Z, Dzogbeta S, Terilli C, Stewart JM. Phenylephrine alteration of cerebral blood flow during orthostasis: effect on n-back performance in chronic fatigue syndrome. J Appl Physiol (1985) 2014; 117:1157-64. [PMID: 25277740 DOI: 10.1152/japplphysiol.00527.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic fatigue syndrome (CFS) with orthostatic intolerance is characterized by neurocognitive deficits and impaired working memory, concentration, and information processing. In CFS, upright tilting [head-up tilt (HUT)] caused decreased cerebral blood flow velocity (CBFv) related to hyperventilation/hypocapnia and impaired cerebral autoregulation; increasing orthostatic stress resulted in decreased neurocognition. We loaded the baroreflex with phenylephrine to prevent hyperventilation and performed n-back neurocognition testing in 11 control subjects and 15 CFS patients. HUT caused a significant increase in heart rate (109.4 ± 3.9 vs. 77.2 ± 1.6 beats/min, P < 0.05) and respiratory rate (20.9 ± 1.7 vs. 14.2 ± 1.2 breaths/min, P < 0.05) and decrease in end-tidal CO2 (ETCO2; 42.8 ± 1.2 vs. 33.9 ± 1.1 Torr, P < 0.05) in CFS vs. control. HUT caused CBFv to decrease 8.7% in control subjects but fell 22.5% in CFS. In CFS, phenylephrine prevented the HUT-induced hyperventilation/hypocapnia and the significant drop in CBFv with HUT (-8.1% vs. -22.5% untreated). There was no difference in control subject n-back normalized response time (nRT) comparing supine to HUT (106.1 ± 6.9 vs. 97.6 ± 7.1 ms at n = 4), and no difference comparing control to CFS while supine (97.1 ± 7.1 vs 96.5 ± 3.9 ms at n = 4). However, HUT of CFS subjects caused a significant increase in nRT (148.0 ± 9.3 vs. 96.4 ± 6.0 ms at n = 4) compared with supine. Phenylephrine significantly reduced the HUT-induced increase in nRT in CFS to levels similar to supine (114.6 ± 7.1 vs. 114.6 ± 9.3 ms at n = 4). Compared with control subjects, CFS subjects are more sensitive both to orthostatic challenge and to baroreflex/chemoreflex-mediated interventions. Increasing blood pressure with phenylephrine can alter CBFv. In CFS subjects, mitigation of the HUT-induced CBFv decrease with phenylephrine has a beneficial effect on n-back outcome.
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Affiliation(s)
- Marvin S Medow
- Department of Pediatrics, New York Medical College, Valhalla, New York; and Department of Physiology, New York Medical College, Valhalla, New York
| | - Shilpa Sood
- Department of Pediatrics, New York Medical College, Valhalla, New York; and
| | - Zachary Messer
- Department of Pediatrics, New York Medical College, Valhalla, New York; and
| | - Seli Dzogbeta
- Department of Pediatrics, New York Medical College, Valhalla, New York; and
| | - Courtney Terilli
- Department of Pediatrics, New York Medical College, Valhalla, New York; and
| | - Julian M Stewart
- Department of Pediatrics, New York Medical College, Valhalla, New York; and Department of Physiology, New York Medical College, Valhalla, New York
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Anderson JW, Lambert EA, Sari CI, Dawood T, Esler MD, Vaddadi G, Lambert GW. Cognitive function, health-related quality of life, and symptoms of depression and anxiety sensitivity are impaired in patients with the postural orthostatic tachycardia syndrome (POTS). Front Physiol 2014; 5:230. [PMID: 25009504 PMCID: PMC4070177 DOI: 10.3389/fphys.2014.00230] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 06/02/2014] [Indexed: 01/11/2023] Open
Abstract
The Postural Orthostatic Tachycardia Syndrome (POTS) is a condition in which heart rate increases abnormally when the individual assumes an upright position. In addition to the marked tachycardia, presyncope, and syncope, patients with POTS often complain of light-headedness, fatigue, and difficulty in concentrating. The present study assessed individuals with POTS for psychiatric comorbidity, anxiety sensitivity and health related quality of life and examined general cognitive ability. Data was obtained from patients with POTS (n = 15, 12 female, aged 30 ± 3 years) and age matched healthy subjects (n = 30, 21 female, aged 32 ± 2 years). Patients with POTS commonly presented with symptoms of depression, elevated anxiety and increased anxiety sensitivity, particularly with regards to cardiac symptoms, and had a poorer health related quality of life in both the physical and mental health domains. While patients with POTS performed worse in tests of current intellectual functioning (verbal and non-verbal IQ) and in measures of focused attention (digits forward) and short term memory (digits back), test results were influenced largely by years of education and the underlying level of depression and anxiety. Acute changes in cognitive performance in response to head up tilt were evident in the POTS patients. From results obtained, it was concluded that participants with POTS have an increased prevalence of depression and higher levels of anxiety. These underlying symptoms impact on cognition in patients with POTS, particularly in the cognitive domains of attention and short-term memory. Our results indicate that psychological interventions may aid in recovery and facilitate uptake and adherence of other treatment modalities in patients with POTS.
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Affiliation(s)
- Jake W Anderson
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia ; School of Psychology and Psychiatry, Monash University Melbourne, VIC, Australia
| | - Elisabeth A Lambert
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia ; Department of Physiology, Nursing and Health Sciences, Monash University Melbourne, VIC, Australia
| | - Carolina I Sari
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia
| | - Tye Dawood
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia
| | - Murray D Esler
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia ; Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University Melbourne, VIC, Australia
| | - Gautam Vaddadi
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia
| | - Gavin W Lambert
- Baker IDI Heart & Diabetes Institute Melbourne, VIC, Australia ; Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University Melbourne, VIC, Australia
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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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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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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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Transfer function analysis for the assessment of cerebral autoregulation using spontaneous oscillations in blood pressure and cerebral blood flow. Med Eng Phys 2014; 36:563-75. [DOI: 10.1016/j.medengphy.2014.02.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 01/31/2014] [Accepted: 02/03/2014] [Indexed: 12/21/2022]
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Kizilbash SJ, Ahrens SP, Bruce BK, Chelimsky G, Driscoll SW, Harbeck-Weber C, Lloyd RM, Mack KJ, Nelson DE, Ninis N, Pianosi PT, Stewart JM, Weiss KE, Fischer PR. Adolescent fatigue, POTS, and recovery: a guide for clinicians. Curr Probl Pediatr Adolesc Health Care 2014; 44:108-33. [PMID: 24819031 PMCID: PMC5819886 DOI: 10.1016/j.cppeds.2013.12.014] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 10/22/2013] [Accepted: 12/13/2013] [Indexed: 12/15/2022]
Abstract
Many teenagers who struggle with chronic fatigue have symptoms suggestive of autonomic dysfunction that may include lightheadedness, headaches, palpitations, nausea, and abdominal pain. Inadequate sleep habits and psychological conditions can contribute to fatigue, as can concurrent medical conditions. One type of autonomic dysfunction, postural orthostatic tachycardia syndrome, is increasingly being identified in adolescents with its constellation of fatigue, orthostatic intolerance, and excessive postural tachycardia (more than 40 beats/min). A family-based approach to care with support from a multidisciplinary team can diagnose, treat, educate, and encourage patients. Full recovery is possible with multi-faceted treatment. The daily treatment plan should consist of increased fluid and salt intake, aerobic exercise, and regular sleep and meal schedules; some medications can be helpful. Psychological support is critical and often includes biobehavioral strategies and cognitive-behavioral therapy to help with symptom management. More intensive recovery plans can be implemented when necessary.
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Affiliation(s)
- Sarah J Kizilbash
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Shelley P Ahrens
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Barbara K Bruce
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Gisela Chelimsky
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | | | | | - Robin M Lloyd
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Kenneth J Mack
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Dawn E Nelson
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Nelly Ninis
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Paolo T Pianosi
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Julian M Stewart
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Karen E Weiss
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Philip R Fischer
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
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48
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Esler M. Sympathetic nervous system moves toward center stage in cardiovascular medicine: from Thomas Willis to resistant hypertension. Hypertension 2014; 63:e25-32. [PMID: 24420544 DOI: 10.1161/hypertensionaha.113.02439] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Murray Esler
- Baker IDI Heart and Diabetes Institute, PO Box 6492 St Kilda Rd Central, Melbourne, Victoria 8008, Australia.
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What is brain fog? An evaluation of the symptom in postural tachycardia syndrome. Clin Auton Res 2013; 23:305-11. [PMID: 23999934 DOI: 10.1007/s10286-013-0212-z] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 08/12/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE Adolescents with postural tachycardia syndrome (POTS) often experience ill-defined cognitive impairment referred to by patients as "brain fog." The objective of this study was to evaluate the symptom of brain fog as a means of gaining further insight into its etiology and potential palliative interventions. METHODS Eligible subjects who reported having been diagnosed with POTS were recruited from social media web sites. Subjects were asked to complete a 38-item questionnaire designed for this study, and the Wood mental fatigue inventory (WMFI). RESULTS Responses were received from 138 subjects with POTS (88 % female), ranging in age from 14 to 29 years; 132 subjects reported brain fog. WMFI scores correlated with brain fog frequency and severity (P < 0.001). The top ranked descriptors of brain fog were "forgetful," "cloudy," and "difficulty focusing, thinking and communicating." The most frequently reported brain fog triggers were fatigue (91 %), lack of sleep (90 %), prolonged standing (87 %), dehydration (86 %), and feeling faint (85 %). Although aggravated by upright posture, brain fog was reported to persist after assuming a recumbent posture. The most frequently reported interventions for the treatment of brain fog were intravenous saline (77 %), stimulant medications (67 %), salt tablets (54 %), intra-muscular vitamin B-12 injections (48 %), and midodrine (45 %). CONCLUSIONS Descriptors for "brain fog" are most consistent with it being a cognitive complaint. Factors other than upright posture may play a role in the persistence of this symptom. Subjects reported a number of therapeutic interventions for brain fog not typically used in the treatment of POTS that may warrant further investigation.
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50
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Stewart JM. Update on the theory and management of orthostatic intolerance and related syndromes in adolescents and children. Expert Rev Cardiovasc Ther 2013; 10:1387-99. [PMID: 23244360 DOI: 10.1586/erc.12.139] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Orthostasis means standing upright. One speaks of orthostatic intolerance (OI) when signs, such as hypotension, and symptoms, such as lightheadedness, occur when upright and are relieved by recumbence. The experience of transient mild OI is part of daily life. 'Initial orthostatic hypotension' on rapid standing is a normal form of OI. However, other people experience OI that seriously interferes with quality of life. These include episodic acute OI, in the form of postural vasovagal syncope, and chronic OI, in the form of postural tachycardia syndrome. Less common is neurogenic orthostatic hypotension, which is an aspect of autonomic failure. Normal orthostatic physiology and potential mechanisms for OI are discussed, including forms of sympathetic hypofunction, forms of sympathetic hyperfunction and OI that results from regional blood volume redistribution. General and specific treatment options are proposed.
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Affiliation(s)
- Julian M Stewart
- Departments of Pediatrics, Physiology and Medicine, The Maria Fareri Childrens Hospital and New York Medical College, Valhalla, NY, USA.
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