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Hurtado MM, Kaempfer R, Geddes J, Olufsen MS, Rodriguez-Fernandez M. Unraveling autonomic cardiovascular control complexity during orthostatic stress: Insights from a mathematical model. Math Biosci 2024:109306. [PMID: 39395755 DOI: 10.1016/j.mbs.2024.109306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 09/26/2024] [Accepted: 09/30/2024] [Indexed: 10/14/2024]
Abstract
Understanding cardiovascular control mediated by the autonomic system remains challenging due to its inherent complexity. Consequently, syndromes such as orthostatic intolerance continue to evoke debates regarding the underlying pathophysiological mechanisms. This study develops a comprehensive mathematical model simulating the control of the sympathetic branch of the cardiovascular system in individuals with normal and abnormal responses to the head-up-tilt test. We recruited four young women: one control, one with vasovagal syncope, one with orthostatic hypertension, and one with orthostatic hypotension, exposing them to an orthostatic head-up tilt test (HUTT) employing non-invasive methods to measure electrocardiography and continuous blood pressure. Our work encompasses a compartmental model formulated using a system of ordinary differential equations. Using heart rate as input, we predict blood pressure, flow, and volume in compartments representing the veins, arteries, heart, and the sympathetic branch of the baroreflex control system. The latter is modulated by high- and low-pressure baroreceptor afferents activated by changes in blood pressure induced by the HUTT. Sensitivity analysis, parameter subset selection, and optimization are employed to estimate patient-specific parameters associated with autonomic performance. The model has seven sensitive and identifiable parameters with significant physiological relevance that can serve as biomarkers for patient classification. Results show that the model can reproduce a spectrum of blood pressure responses successfully, fitting the trajectory displayed by the experimental data. The controller exhibits behavior that emulates the operation of the sympathetic system. These encouraging findings underscore the potential of computational methods in evaluating pathologies associated with autonomic nervous system control, warranting further exploration and novel approaches.
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Affiliation(s)
- Martin Miranda Hurtado
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Catolica de Chile, Avda.Vicuña Mackenna 4860, Macul, Santiago, 8970117, Chile; Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive, Calgary, T2N 4N1, Canada.
| | - Rafael Kaempfer
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Catolica de Chile, Avda.Vicuña Mackenna 4860, Macul, Santiago, 8970117, Chile.
| | - Justen Geddes
- Department of Mathematics, North Carolina State University, 2311 Stinson Drive, Raleigh, 27695, USA; Computational Modeling of Biological Systems faculty, Biomedical Engineering, Pratt School of Engineering, Duke University, 101 Science Drive, Durham, 27708, USA.
| | - Mette S Olufsen
- Department of Mathematics, North Carolina State University, 2311 Stinson Drive, Raleigh, 27695, USA.
| | - Maria Rodriguez-Fernandez
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Catolica de Chile, Avda.Vicuña Mackenna 4860, Macul, Santiago, 8970117, Chile; Millenium Institute for Intelligent Healthcare Engineering iHEALTH, Avda.Vicuña Mackenna 4860, Macul, Santiago, 8970117, Chile.
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Gronwald T, Schaffarczyk M, Hoos O. Orthostatic testing for heart rate and heart rate variability monitoring in exercise science and practice. Eur J Appl Physiol 2024:10.1007/s00421-024-05601-4. [PMID: 39259398 DOI: 10.1007/s00421-024-05601-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Accepted: 08/28/2024] [Indexed: 09/13/2024]
Abstract
Orthostatic testing, involving the transition from different body positions (e.g., from lying or sitting position to an upright or standing position), offers valuable insights into the autonomic nervous system (ANS) functioning and cardiovascular regulation reflected through complex adjustments in, e.g., measures of heart rate (HR) and heart rate variability (HRV). This narrative review explores the intricate physiological mechanisms underlying orthostatic stress responses and evaluates its significance for exercise science and sports practice. Into this matter, active orthostatic testing (e.g., active standing up) challenges the cardiovascular autonomic function in a different way than a passive tilt test. It is well documented that there is a transient reduction in blood pressure while standing up, leading to a reflex increase in HR and peripheral vasoconstriction. After that acute response systolic and diastolic blood pressures are usually slightly increased compared to supine lying body position. The ANS response to standing is initiated by instantaneous cardiac vagal withdrawal, followed by sympathetic activation and vagal reactivation over the first 25-30 heartbeats. Thus, HR increases immediately upon standing, peaking after 15-20 beats, and is less marked during passive tilting due to the lack of muscular activity. Standing also decreases vagally related HRV indices compared to the supine position. In overtrained endurance athletes, both parasympathetic and sympathetic activity are attenuated in supine and standing positions. Their response to standing is lower than in non-overtrained athletes, with a tendency for further decreased HRV as a sign of pronounced vagal withdrawal and, in some cases, decreased sympathetic excitability, indicating a potential overtraining state. However, as a significant main characteristic, it could be noted that additional pathophysiological conditions consist in a reduced responsiveness or counter-regulation of neural drive in ANS according to an excitatory stimulus, such as an orthostatic challenge. Hence, especially active orthostatic testing could provide additional information about HR(V) reactivity and recovery giving valuable insights into athletes' training status, fatigue levels, and adaptability to workload. Measuring while standing might also counteract the issue of parasympathetic saturation as a common phenomenon especially in well-trained endurance athletes. Data interpretation should be made within intra-individual data history in trend analysis accounting for inter-individual variations in acute responses during testing due to life and physical training stressors. Therefore, additional measures (e.g., psychometrical scales) are required to provide context for HR and HRV analysis interpretation. However, incidence of orthostatic intolerance should be evaluated on an individual level and must be taken into account when considering to implement orthostatic testing in specific subpopulations. Recommendations for standardized testing procedures and interpretation guidelines are developed with the overall aim of enhancing training and recovery strategies. Despite promising study findings in the above-mentioned applied fields, further research, thorough method comparison studies, and systematic reviews are needed to assess the overall perspective of orthostatic testing for training monitoring and fine-tuning of different populations in exercise science and training.
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Affiliation(s)
- Thomas Gronwald
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Am Kaiserkai 1, 20457, Hamburg, Germany.
- G-Lab, Faculty of Applied Sport Sciences and Personality, BSP Business and Law School, Berlin, Germany.
| | - Marcelle Schaffarczyk
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Am Kaiserkai 1, 20457, Hamburg, Germany
| | - Olaf Hoos
- Center for Sports and Physical Education, Faculty of Human Sciences, Julius-Maximilians-University Wuerzburg, Würzburg, Germany
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Furian M, Ulliel-Roche M, Howe CA, Zerizer F, Marillier M, Bernard AC, Hancco I, Champigneulle B, Baillieul S, Stauffer E, Pichon AP, Doutreleau S, Verges S, Brugniaux JV. Cerebral homeostasis and orthostatic responses in residents of the highest city in the world. Sci Rep 2024; 14:17732. [PMID: 39085313 PMCID: PMC11291767 DOI: 10.1038/s41598-024-68389-5] [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: 05/18/2023] [Accepted: 07/23/2024] [Indexed: 08/02/2024] Open
Abstract
Permanent residence at high-altitude and chronic mountain sickness (CMS) may alter the cerebrovascular homeostasis and orthostatic responses. Healthy male participants living at sea-level (LL; n = 15), 3800 m (HL3800m; n = 13) and 5100 m (HL5100m; n = 17), respectively, and CMS highlanders living at 5100 m (n = 31) were recruited. Middle cerebral artery mean blood flow velocity (MCAv), cerebral oxygen delivery (CDO2), mean blood pressure (MAP), heart rate variability and spontaneuous cardiac baroreflex sensitivity (cBRS) were assessed while sitting, initial 30 s and after 3 min of standing. Cerebral autoregulation index (ARI) was estimated (ΔMCAv%baseline)/ΔMAP%baseline) in response to the orthostatic challenge. Altitude and CMS were associated with hypoxemia and elevated hemoglobin concentration. While sitting, MCAv and LFpower negatively correlated with altitude but were not affected by CMS. CDO2 remained preserved. BRS was comparable across all altitudes, but lower with CMS. Within initial 30 s of standing, altitude and CMS correlated with a lesser ΔMAP while ARI remained unaffected. After 3 min standing, MCAv, CDO2 and cBRS remained preserved across altitudes. The LF/HF ratio increased in HL5100m compared to LL and HL3800m from sitting to standing. In contrary, CMS showed blunted autonomic nervous activation in responses to standing. Despite altitude- and CMS-associated hypoxemia, erythrocytosis and impaired blood pressure regulation (CMS only), cerebral homeostasis remained overall preserved.
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Affiliation(s)
- M Furian
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France.
- Swiss University of Traditional Chinese Medicine, Bad Zurzach, Switzerland.
| | - M Ulliel-Roche
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - C A Howe
- Center for Heart, Lung, and Vascular Health, University of British Columbia, Kelowna, BC, Canada
| | - F Zerizer
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - M Marillier
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - A C Bernard
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - I Hancco
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - B Champigneulle
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - S Baillieul
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - E Stauffer
- Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM) EA7424, Team « Vascular Biology and Red Blood Cell », Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - A P Pichon
- Laboratory Mobility, aging & exercise (MOVE, EA6314), Faculty of Sport Sciences, University of Poitiers, Poitiers, France
| | - S Doutreleau
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - S Verges
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
| | - J V Brugniaux
- HP2 Laboratory, Université Grenoble Alpes, Inserm (U1300), CHU Grenoble Alpes, 38000, Grenoble, France
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Fisher JT, Ciuha U, Mekjavić IB. The combined effects of temperature and posture on regional blood flow and haemodynamics. J Therm Biol 2024; 123:103937. [PMID: 39111062 DOI: 10.1016/j.jtherbio.2024.103937] [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: 04/24/2024] [Revised: 06/23/2024] [Accepted: 07/31/2024] [Indexed: 08/23/2024]
Abstract
Under simultaneous ambient temperature and postural stressors, integrated regional blood flow responses are required to maintain blood pressure and thermoregulatory homeostasis. The aim of the present study was to assess the effect of ambient temperature and body posture on regional regulation of microvascular blood flow, specifically in the arms and legs. Participants (N = 11) attended two sessions in which they experienced transient ambient conditions, in a climatic chamber. During each 60-min trial, ambient temperature increased from 15.7 (0.6) °C to 38.9 (0.6) °C followed by a linear decrease, and the participants were either standing or in a supine position throughout the trial; relative humidity in the chamber was maintained at 25.9 (6.6) %. Laser doppler flowmetry of the forearm (SkBFarm) and calf (SkBFcalf), and haemodynamic responses (heart rate, HR; stroke volume, SV; cardiac output, CO; blood pressure, BP), were measured continuously. Analyses of heart rate variability and wavelet transform were also conducted. SkBFarm increased significantly at higher ambient temperatures (p = 0.003), but not SkBFcalf. The standing posture caused lower overall SkBF in both regions throughout the protocol, regardless of temperature (p < 0.001). HR and BP were significantly elevated, and SV significantly lowered, in response to separate and combined effects of higher ambient temperatures and a standing position (all p < 0.05); CO remained unchanged. Mechanistic analyses identified greater sympathetic nerve activation, and higher calf myogenic activation at peak temperatures, in the standing condition. Mechanistically and functionally, arm vasculature responds to modulation from both thermoregulation and baroreceptor activity. The legs, meanwhile, are more sensitive to baroreflex regulatory mechanisms.
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Affiliation(s)
- Jason T Fisher
- Department of Automatics, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia; International Postgraduate School Jozef Stefan, Jamova 39, SI-1000, Ljubljana, Slovenia
| | - Urša Ciuha
- Department of Automatics, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia
| | - Igor B Mekjavić
- Department of Automatics, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.
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Xue F, Knight S, Connolly E, O’Halloran A, Shirsath MA, Newman L, Duggan E, Kenny RA, Romero-Ortuno R. Were Frailty Identification Criteria Created Equal? A Comparative Case Study on Continuous Non-Invasively Collected Neurocardiovascular Signals during an Active Standing Test in the Irish Longitudinal Study on Ageing (TILDA). SENSORS (BASEL, SWITZERLAND) 2024; 24:442. [PMID: 38257535 PMCID: PMC10818961 DOI: 10.3390/s24020442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/22/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024]
Abstract
BACKGROUND In this observational study, we compared continuous physiological signals during an active standing test in adults aged 50 years and over, characterised as frail by three different criteria, using data from The Irish Longitudinal Study on Ageing (TILDA). METHODS This study utilised data from TILDA, an ongoing landmark prospective cohort study of community-dwelling adults aged 50 years or older in Ireland. The initial sampling strategy in TILDA was based on random geodirectory sampling. Four independent groups were identified: those characterised as frail only by one of the frailty tools used (the physical Frailty Phenotype (FP), the 32-item Frailty Index (FI), or the Clinical Frailty Scale (CFS) classification tree), and a fourth group where participants were not characterised as frail by any of these tools. Continuous non-invasive physiological signals were collected during an active standing test, including systolic (sBP) and diastolic (dBP) blood pressure, as well as heart rate (HR), using digital artery photoplethysmography. Additionally, the frontal lobe cerebral oxygenation (Oxy), deoxygenation (Deoxy), and tissue saturation index (TSI) were also non-invasively measured using near-infrared spectroscopy (NIRS). The signals were visualised across frailty groups and statistically compared using one-dimensional statistical parametric mapping (SPM). RESULTS A total of 1124 participants (mean age of 63.5 years; 50.2% women) were included: 23 were characterised as frail only by the FP, 97 by the FI, 38 by the CFS, and 966 by none of these criteria. The SPM analyses revealed that only the group characterised as frail by the FI had significantly different signals (p < 0.001) compared to the non-frail group. Specifically, they exhibited an attenuated gain in HR between 10 and 15 s post-stand and larger deficits in sBP and dBP between 15 and 20 s post-stand. CONCLUSIONS The FI proved to be more adept at capturing distinct physiological responses to standing, likely due to its direct inclusion of cardiovascular morbidities in its definition. Significant differences were observed in the dynamics of cardiovascular signals among the frail populations identified by different frailty criteria, suggesting that caution should be taken when employing frailty identification tools on physiological signals, particularly the neurocardiovascular signals in an active standing test.
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Affiliation(s)
- Feng Xue
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Silvin Knight
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Emma Connolly
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Aisling O’Halloran
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Morgana Afonso Shirsath
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Louise Newman
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Eoin Duggan
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Rose Anne Kenny
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Roman Romero-Ortuno
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
- The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, D02 PN40 Dublin, Ireland
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Hammer SB, Strale F, Williams TB, Kemp Van Ee SL, Agnew JW. Insult of Ultraendurance Events on Blood Pressure: A Systematic Review and Meta-Analysis. Cureus 2023; 15:e46801. [PMID: 37954749 PMCID: PMC10634893 DOI: 10.7759/cureus.46801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 10/07/2023] [Indexed: 11/14/2023] Open
Abstract
The rise of ultraendurance sports in the past two decades warrants evaluation of the impact on the heart and vessels of a growing number of athletes participating. Blood pressure is a simple, inexpensive method to evaluate one dimension of an athlete's cardiovascular health. No systematic review or meta-analysis to date has chronicled and delineated the effects of ultraendurance races, such as ultramarathons, marathons, half-marathons, and Ironman triathlon events, specifically on heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), and mean arterial pressure (MAP) measurements in supine and standing positions before and after the event. This meta-analysis reviews the effects of ultraendurance events on positional and calculated hemodynamic values. Data were extracted from 38 studies and analyzed using a random effects model with a total of 1,645 total blood pressure measurements. Of these, 326 values were obtained from a standing position, and 1,319 blood pressures were taken supine. Pre-race and post-race measurements were evaluated for clinical significance using established standards of hypotension and orthostasis. HR and calculated BP features, such as PP and MAP, were evaluated. Across all included studies, the mean supine post-race HR increased by 21±8 beats per minute (bpm) compared to pre-race values. The mean standing post-race HR increased by 23±14 bpm when compared with pre-race HR. Overall, there was a mean SBP decrease of 19±9 mmHg and a DBP decrease of 9±5 mmHg post-race versus pre-race values. MAP variations reflected SBP and DBP changes. The mean supine and standing pre-race blood pressures across studies were systolic (126±7; 124±14) and diastolic (76±6; 75±12), suggesting that some athletes may enter races with existing hypertension. The post-race increase in the mean HR and decline in mean blood pressure across examined studies suggest that during long-term events, ultramarathon athletes perform with relatively asymptomatic hypotension.
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Affiliation(s)
- Steven B Hammer
- Anatomy and Physiology, Indian River State College, Fort Pierce, USA
| | - Fred Strale
- Statistics, Wayne State University, Detroit, USA
| | - Timothy B Williams
- Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, USA
| | - Shantele L Kemp Van Ee
- Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, USA
| | - James W Agnew
- Anatomy and Physiology, Indian River State College, Fort Pierce, USA
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Zawadka-Kunikowska M, Rzepiński Ł, Cieślicka M, Klawe JJ, Tafil-Klawe M. Association between Daytime Sleepiness, Fatigue and Autonomic Responses during Head-Up Tilt Test in Multiple Sclerosis Patients. Brain Sci 2023; 13:1342. [PMID: 37759943 PMCID: PMC10526123 DOI: 10.3390/brainsci13091342] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/10/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
We aimed to assess dynamic changes in hemodynamic and autonomic function in response to the head-up tilt test (HUTT) in patients with multiple sclerosis (MS) compared to healthy controls (HCs) and evaluate its relationship with the patients' reported daytime sleepiness and fatigue symptoms. A total of 58 MS patients and 30 HCs were included in the analysis. Fatigue and sleepiness were evaluated using the Chalder Fatigue Scale (CFQ) and the Epworth Sleepiness Scale (ESS), respectively. Hemodynamic response, baroreflex sensitivity, heart rate variability, and systolic and diastolic blood pressure (BP) variability (SBPV, DBPV) parameters were calculated at rest, and in response to the HUTT. The MS patients displayed attenuated BP responses coupled with a more pronounced decrease in cardiac index as well as a reduced increase in the low frequency (LFnu) of DBPV (p = 0.021) and the sympathovagal ratio (p = 0.031) in the latter-phase orthostatic challenge compared to HCs. In MS patients, the ESS score showed no correlation with CFQ or clinical disease outcomes, but exhibited a moderate correlation with LFnu of BPVrest. Fatigue and disease variants predicted blood pressure response to HUTT. These findings underscore the importance of subjective daytime sleepiness and fatigue symptoms and their role in blood pressure regulation in MS patients.
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Affiliation(s)
- Monika Zawadka-Kunikowska
- Department of Human Physiology, Nicolaus Copernicus University, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Karłowicza 24, 85-092 Bydgoszcz, Poland; (M.C.); (M.T.-K.)
| | - Łukasz Rzepiński
- Sanitas–Neurology Outpatient Clinic, Dworcowa 110, 85-010 Bydgoszcz, Poland;
- Department of Neurology, 10th Military Research Hospital and Polyclinic, 85-681 Bydgoszcz, Poland
| | - Mirosława Cieślicka
- Department of Human Physiology, Nicolaus Copernicus University, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Karłowicza 24, 85-092 Bydgoszcz, Poland; (M.C.); (M.T.-K.)
| | - Jacek J. Klawe
- Department of Hygiene, Epidemiology, Ergonomy and Postgraduate Education, Nicolaus Copernicus University, Ludwik Rydygier Collegium Medicum in Bydgoszcz, M. Sklodowskiej-Curie 9, 85-094 Bydgoszcz, Poland;
| | - Małgorzata Tafil-Klawe
- Department of Human Physiology, Nicolaus Copernicus University, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Karłowicza 24, 85-092 Bydgoszcz, Poland; (M.C.); (M.T.-K.)
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Gobezie NZ, Endalew NS, Tawuye HY, Aytolign HA. Prevalence and associated factors of postoperative orthostatic intolerance at University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia, 2022: cross sectional study. BMC Surg 2023; 23:108. [PMID: 37127603 PMCID: PMC10150513 DOI: 10.1186/s12893-023-02015-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 04/24/2023] [Indexed: 05/03/2023] Open
Abstract
BACKGROUND Postoperative orthostatic intolerance is an inability to maintain an upright position because of symptoms of cerebral hypoperfusion. It is a common problem in the early postoperative period and hinders early mobilization, however, there is limited information about factors associated with it. Thus, the main aim of this study was to determine the prevalence and identify factors associated with postoperative orthostatic intolerance. METHOD Hospital based cross-sectional study was conducted from April 08 to July 20, 2022, at University of Gondar comprehensive Specialized Hospital. A semi-structured questionnaire containing sociodemographic variables and perioperative factors related to anesthesia and surgery was used for data collection. The presence of postoperative orthostatic intolerance during the first ambulation was evaluated with a standardized symptom checklist which contains symptoms of orthostatic intolerance. Binary logistic regression analysis was performed to assess factors associated with postoperative orthostatic intolerance. In multivariable regression, variables with P-value < 0.05 were considered statistically significant. RESULT A total of 420 patients were included in this study with a response rate of 99.06%. Postoperative orthostatic intolerance was experienced in 254 (60.5%) participants. Being female (AOR = 2.27; 95% CI = 1.06-4.86), low BMI (AOR = 0.79; 95% CI = 0.71-0.95), ASA II and above (AOR = 3.34; 95% CI = 1.34-8.28), low diastolic blood pressure (AOR = 0.82; 95% CI = 0.88-0.99), general anesthesia (AOR = 3.26, 95% CI = 1.31-8.12), high intraoperative blood lose (AOR = 0.93, 95% CI = 0.88-0.99), high postoperative fluid intake (AOR = 2.09, 95% CI = 1.23-3.55), pain before ambulation (AOR = 1.99, 95% CI = 1.28-3.11) and pain during ambulation (AOR = 1.82, 95% CI = 1.23-2.69) were the significant factors associated with orthostatic intolerance. CONCLUSION Our study revealed that postoperative orthostatic intolerance was experienced in nearly two-thirds of participants. During the time of ambulation, assessing patients for the presence of orthostatic intolerance is necessary to reduce the adverse effects of postoperative OI. In addition, maintaining preoperative normotension, reducing intraoperative blood loss and optimizing postoperative pain control is recommended to reduce the risk of postoperative orthostatic intolerance.
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Affiliation(s)
- Negesse Zurbachew Gobezie
- Department of Anesthesia, College of Medicine and Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia.
| | - Nigussie Simeneh Endalew
- Department of Anesthesia, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
| | - Hailu Yimer Tawuye
- Department of Anesthesia, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
| | - Habtu Adane Aytolign
- Department of Anesthesia, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia
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de Oliveira MDCS, Távora-Mehta MZP, Mehta N, Magajevski AS, Concato L, Ortiz MR, Doubrawa E, Lofrano-Alves MS. Distinct Hemodynamic Responses That Culminate With Postural Orthostatic Tachycardia Syndrome. Am J Cardiol 2023; 197:3-12. [PMID: 37104891 DOI: 10.1016/j.amjcard.2023.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/08/2023] [Accepted: 03/26/2023] [Indexed: 04/29/2023]
Abstract
It is of paramount importance to characterize the individual hemodynamic response of patients with postural orthostatic tachycardia syndrome (POTS) to select the best therapeutic intervention. Our aim in this study was to describe the hemodynamic changes in 40 patients with POTS during the head-up tilt test and compare them with 48 healthy patients. Hemodynamic parameters were obtained by cardiac bioimpedance. Patients were compared in supine position and after 5, 10, 15, and 20 minutes of orthostatic position. Patients with POTS demonstrated higher heart rate (74 beats per minute [64 to 80] vs 67 [62 to 72], p <0.001) and lower stroke volume (SV) (83.0 ml [72 to 94] vs 90 [79 to 112], p <0.001) at supine position. The response to orthostatic challenge was characterized by a decrease in SV index (SVI) in both groups (ΔSVI in ml/m2: -16 [-25 to -7.] vs -11 [-17 to -6.1], p = NS). Peripheral vascular resistance (PVR) was reduced only in POTS (ΔPVR in dyne.seg/cm5:-52 [-279 to 163] vs 326 [58 to 535], p <0.001). According to the best cut-off points obtained using the receiver operating characteristic analysis for the variation of SVI (-15.5%) and PVR index (PVRI) (-5.5%), we observed 4 distinct groups of POTS: 10% presented an increase in both SVI and PVRI after the orthostatic challenge, 35% presented a PVRI decrease with SVI maintenance or increase, 37.5% presented an SVI decrease with PVRI maintenance or elevation, and 17.5% presented a reduction in both variables. Body mass index, ΔSVI, and ΔPVRI were strongly correlated with POTS (area under the curve = 0.86 [95% confidence interval 0.77 to 0.92], p <0.0001). In conclusion, the use of appropriate cut-off points for hemodynamic parameters using bioimpedance cardiography during the head-up tilt test could be a useful strategy to identify the main mechanism involved and to select the best individual therapeutic strategy in POTS.
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Affiliation(s)
| | - Maria Zildany P Távora-Mehta
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Niraj Mehta
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Adriano Senter Magajevski
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Leticia Concato
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Marcio Rogerio Ortiz
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Eduardo Doubrawa
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil
| | - Marco Stephan Lofrano-Alves
- Postgraduate Program in Internal Medicine, Internal Medicine Department, Federal University of Parana, Curitiba, Parana, Brazil.
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10
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Dumančić D, Stupin A, Kožul M, Šerić V, Kibel A, Goswami N, Brix B, Debeljak Ž, Scitovski R, Drenjančević I. Increased cerebral vascular resistance underlies preserved cerebral blood flow in response to orthostasis in humans on a high-salt diet. Eur J Appl Physiol 2023; 123:923-933. [PMID: 36598577 DOI: 10.1007/s00421-022-05124-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 12/20/2022] [Indexed: 01/05/2023]
Abstract
Cerebral blood flow autoregulation protects brain tissue from blood pressure variations and maintains cerebral perfusion pressure by changes in vascular resistance. High salt (HS) diet impairs endothelium-dependent vasodilation in many vascular beds, including cerebral microcirculation, and may affect vascular resistance. The aim of present study was to determine if 7-day HS diet affected the reactivity of middle cerebral artery (MCA) to orthostatic challenge in healthy human individuals, and if autoregulatory mechanisms and sympathetic neural regulation were involved in this phenomenon.Twenty-seven persons participated in study (F:21, M:6, age range 19-24). Participants consumed 7-day low-salt (LS) diet (< 2.3 g kitchen salt/day) and afterwards 7-day HS diet (> 11.2 g kitchen salt/day). Blood and urine analysis and anthropometric measurements were performed after each diet. Arterial blood pressure, heart rate and heart rate variability, and cerebral and systemic hemodynamic parameters were recorded simultaneously with transcranial Doppler ultrasound and The Task Force® Monitor in response to orthostatic test.Participants remained normotensive during HS diet. Following both, the LS and HS dietary protocols, mean cerebral blood flow (CBF), as well as the velocity time integral and diastolic blood pressure decreased, and cerebral pulsatility index increased after rising up. Importantly, cerebrovascular resistance significantly increased in response to orthostasis only after HS diet. Urine concentration of noradrenaline and vanillylmandelic acid, baroreflex sensitivity (BRS), and sympathetic neural control was significantly decreased in HS diet.Results suggest that CBF in response to orthostatic test was preserved in HS condition due to altered vascular reactivity of MCA, with increased cerebrovascular resistance and blunted BRS and sympathetic activity.
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Affiliation(s)
- Dijana Dumančić
- Department of Physiology and Immunology, Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, J. Huttlera 4, 31000, Osijek, Croatia
- Department of Diagnostic and Interventional Radiology, University Hospital Centre Osijek, J. Huttlera 4, 31000, Osijek, Croatia
| | - Ana Stupin
- Department of Physiology and Immunology, Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, J. Huttlera 4, 31000, Osijek, Croatia
| | - Maja Kožul
- Department of Dermatology and Venereology, University Hospital Centre Osijek, J. Huttlera 4, 31000, Osijek, Croatia
| | - Vatroslav Šerić
- Department of Clinical Laboratory Diagnostics, University Hospital Centre Osijek, J. Huttlera 4, 31000, Osijek, Croatia
| | - Aleksandar Kibel
- Department of Physiology and Immunology, Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, J. Huttlera 4, 31000, Osijek, Croatia
- Department of Heart and Vascular Diseases, University Hospital Centre Osijek, J. Huttlera 4, 31000, Osijek, Croatia
| | - Nandu Goswami
- Physiology Division, Otto Loewi Research Center, Medical University of Graz, Auenbruggerplatz 2, 8036, Graz, Austria
| | - Bianca Brix
- Physiology Division, Otto Loewi Research Center, Medical University of Graz, Auenbruggerplatz 2, 8036, Graz, Austria
| | - Željko Debeljak
- Department of Clinical Laboratory Diagnostics, University Hospital Centre Osijek, J. Huttlera 4, 31000, Osijek, Croatia
- Department of Pharmacology, Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, J. Huttlera 4, 31000, Osijek, Croatia
| | - Rudolf Scitovski
- Department of Mathematics, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Ines Drenjančević
- Department of Physiology and Immunology, Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, J. Huttlera 4, 31000, Osijek, Croatia.
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11
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Richardson CE, Tovar AP, Davis BA, Van Loan MD, Keim NL, Casazza GA. An Intervention of Four Weeks of Time-Restricted Eating (16/8) in Male Long-Distance Runners Does Not Affect Cardiometabolic Risk Factors. Nutrients 2023; 15:nu15040985. [PMID: 36839342 PMCID: PMC9961388 DOI: 10.3390/nu15040985] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023] Open
Abstract
Timing of nutrient intake for athletes may affect exercise performance and cardiometabolic factors. Our objective was to examine the effect of time-restricted eating (TRE) on cardiometabolic health. Using a cross-over study design, 15 endurance-trained male runners were randomized to either a normal dietary pattern (ND) first (12 h eating/fasting times) followed by time-restricted eating (TRE) pattern (16 h fast; 8 h eating) or the reverse, with a 4-week washout period between interventions. Body composition, resting energy expenditure, blood pressure and serum insulin, glucose and lipids were measured using standard laboratory methods. Exercise training and dietary intake (calories and macronutrients) were similar across interventions. No significant differences were observed in resting energy expenditure, markers of insulin resistance, serum lipids or blood pressure. Body composition did change significantly (p < 0.05) with whole body fat mass (-0.8 ± 1.3 kg with TRE vs. +0.1 ± 4.3 kg with ND), leg fat mass (-0.3 ± 0.5 kg with TRE vs. +0.1 ± 0.4 kg with ND), and percent body fat (-1.0 ± 1.5% with TRE vs. +0.1 ± 1.3% with ND) declining more in the TRE intervention, with no change in fat-free mass. This study is one of a few to investigate the effects of an isocaloric 16/8 TRE eating pattern in trained endurance athletes and confirms no change in cardiometabolic risk factors. In conclusion, TRE is not detrimental to cardiometabolic health in endurance-trained male runners but could be beneficial on exercise performance by reducing fat mass.
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Affiliation(s)
- Christine E. Richardson
- Department of Nutrition, University of California, Davis, CA 95616, USA
- USDA, ARS, Western Human Nutrition Research Center, Davis, CA 95616, USA
| | - Ashley P. Tovar
- Department of Nutrition, University of California, Davis, CA 95616, USA
- USDA, ARS, Western Human Nutrition Research Center, Davis, CA 95616, USA
| | - Brian A. Davis
- Physical Medicine and Rehabilitation, University of California Davis Medical Center, Sacramento, CA 95816, USA
| | - Marta D. Van Loan
- Department of Nutrition, University of California, Davis, CA 95616, USA
- USDA, ARS, Western Human Nutrition Research Center, Davis, CA 95616, USA
| | - Nancy L. Keim
- Department of Nutrition, University of California, Davis, CA 95616, USA
- USDA, ARS, Western Human Nutrition Research Center, Davis, CA 95616, USA
| | - Gretchen A. Casazza
- Department of Kinesiology, California State University, Sacramento, CA 95819, USA
- Correspondence:
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12
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Xue F, Monaghan A, Jennings G, Byrne L, Foran T, Duggan E, Romero-Ortuno R. A Novel Methodology for the Synchronous Collection and Multimodal Visualization of Continuous Neurocardiovascular and Neuromuscular Physiological Data in Adults with Long COVID. SENSORS (BASEL, SWITZERLAND) 2022; 22:1758. [PMID: 35270905 PMCID: PMC8914998 DOI: 10.3390/s22051758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/13/2022] [Accepted: 02/16/2022] [Indexed: 12/12/2022]
Abstract
Background: Reports suggest that adults with post-COVID-19 syndrome or long COVID may be affected by orthostatic intolerance syndromes, with autonomic nervous system dysfunction as a possible causal factor of neurocardiovascular instability (NCVI). Long COVID can also manifest as prolonged fatigue, which may be linked to neuromuscular function impairment (NMFI). The current clinical assessment for NCVI monitors neurocardiovascular performance upon the application of orthostatic stressors such as an active (i.e., self-induced) stand or a passive (tilt table) standing test. Lower limb muscle contractions may be important in orthostatic recovery via the skeletal muscle pump. In this study, adults with long COVID were assessed with a protocol that, in addition to the standard NCVI tests, incorporated simultaneous lower limb muscle monitoring for NMFI assessment. Methods: To conduct such an investigation, a wide range of continuous non-invasive biomedical sensing technologies were employed, including digital artery photoplethysmography for the extraction of cardiovascular signals, near-infrared spectroscopy for the extraction of regional tissue oxygenation in brain and muscle, and electromyography for assessment of timed muscle contractions in the lower limbs. Results: With the proposed methodology described and exemplified in this paper, we were able to collect relevant physiological data for the assessment of neurocardiovascular and neuromuscular functioning. We were also able to integrate signals from a variety of instruments in a synchronized fashion and visualize the interactions between different physiological signals during the combined NCVI/NMFI assessment. Multiple counts of evidence were collected, which can capture the dynamics between skeletal muscle contractions and neurocardiovascular responses. Conclusions: The proposed methodology can offer an overview of the functioning of the neurocardiovascular and neuromuscular systems in a combined NCVI/NMFI setup and is capable of conducting comparative studies with signals from multiple participants at any given time in the assessment. This could help clinicians and researchers generate and test hypotheses based on the multimodal inspection of raw data in long COVID and other cohorts.
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Affiliation(s)
- Feng Xue
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02PN40 Dublin, Ireland; (A.M.); (G.J.); (E.D.); (R.R.-O.)
- The Irish Longitudinal Study on Ageing, Trinity College Dublin, D02R590 Dublin, Ireland
| | - Ann Monaghan
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02PN40 Dublin, Ireland; (A.M.); (G.J.); (E.D.); (R.R.-O.)
- The Irish Longitudinal Study on Ageing, Trinity College Dublin, D02R590 Dublin, Ireland
| | - Glenn Jennings
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02PN40 Dublin, Ireland; (A.M.); (G.J.); (E.D.); (R.R.-O.)
- The Irish Longitudinal Study on Ageing, Trinity College Dublin, D02R590 Dublin, Ireland
| | - Lisa Byrne
- Falls and Syncope Unit, Mercer’s Institute for Successful Ageing, St. James’s Hospital, D08E191 Dublin, Ireland;
| | - Tim Foran
- Department of Medical Physics and Bioengineering, Mercer’s Institute for Successful Ageing, St. James’s Hospital, D08E191 Dublin, Ireland;
| | - Eoin Duggan
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02PN40 Dublin, Ireland; (A.M.); (G.J.); (E.D.); (R.R.-O.)
- The Irish Longitudinal Study on Ageing, Trinity College Dublin, D02R590 Dublin, Ireland
- Falls and Syncope Unit, Mercer’s Institute for Successful Ageing, St. James’s Hospital, D08E191 Dublin, Ireland;
| | - Roman Romero-Ortuno
- Discipline of Medical Gerontology, School of Medicine, Trinity College Dublin, D02PN40 Dublin, Ireland; (A.M.); (G.J.); (E.D.); (R.R.-O.)
- The Irish Longitudinal Study on Ageing, Trinity College Dublin, D02R590 Dublin, Ireland
- Falls and Syncope Unit, Mercer’s Institute for Successful Ageing, St. James’s Hospital, D08E191 Dublin, Ireland;
- Global Brain Health Institute, Trinity College Dublin, D02PN40 Dublin, Ireland
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13
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Soulaidopoulos S, Arsenos P, Doundoulakis I, Tsiachris D, Antoniou C, Dilaveris P, Fragakis N, Sotiriadou M, Sideris S, Kordalis A, Laina A, Tousoulis D, Tsioufis K, Gatzoulis KA. Syncope associated with supraventricular tachycardia: Diagnostic role of implantable loop recorders. Ann Noninvasive Electrocardiol 2021; 26:e12850. [PMID: 33955102 PMCID: PMC8411760 DOI: 10.1111/anec.12850] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/23/2021] [Accepted: 03/16/2021] [Indexed: 12/12/2022] Open
Abstract
Syncope represents a relatively uncommon symptom of supraventricular tachycardia (SVT). It is likely that an impaired autonomic vasomotor response to the hemodynamic stress of tachycardia is the determinant of hemodynamic changes leading to cerebral hypoperfusion and syncope. In this regard, tilt-table test may detect abnormalities in the autonomic nervous function and predict the occurrence of syncope during SVT. Electrophysiology studies may reproduce the SVT, distinguish it from other life-threatening ventricular tachyarrhythmias, and exclude other causes of syncope. Not infrequently mixed syncope mechanisms are revealed during the above diagnostic workup raising doubts about the operating mechanism in the clinical setting. In such cases of uncertainty, an implantable loop recorder, providing long-term cardiac monitoring, may play a pivotal role in the establishment of the diagnosis, confirming the association of an arrhythmic event with the symptom. Herein, we present four such cases with recurrent unexplained syncope finally attributed to paroxysmal SVT guiding them to a potentially radical treatment through radiofrequency catheter ablation.
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Affiliation(s)
- Stergios Soulaidopoulos
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Petros Arsenos
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Ioannis Doundoulakis
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | | | - Christos‐Konstantinos Antoniou
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Polychronis Dilaveris
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Nikolaos Fragakis
- Third Department of CardiologyAristotle University of ThessalonikiThessalonikiGreece
| | - Melani Sotiriadou
- Third Department of CardiologyAristotle University of ThessalonikiThessalonikiGreece
| | - Skevos Sideris
- State Department of CardiologyHippokration General HospitalAthensGreece
| | - Athanasios Kordalis
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Ageliki Laina
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Dimitrios Tousoulis
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Konstantinos Tsioufis
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
| | - Konstantinos A. Gatzoulis
- First Department of CardiologySchool of MedicineHippokration General HospitalNational and Kapodistrian University of AthensAthensGreece
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14
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Wang YY, Han ZH, Wang YL, Liao Y, Zhang CY, Liu P, Tang CS, Du JB, Jin HF, Huang YQ. Baseline left ventricular ejection fraction associated with symptom improvements in both children and adolescents with postural tachycardia syndrome under metoprolol therapy. Chin Med J (Engl) 2021; 134:1977-1982. [PMID: 34387611 PMCID: PMC8382470 DOI: 10.1097/cm9.0000000000001698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Postural tachycardia syndrome (POTS) is a common childhood disease that seriously affects the patient's physical and mental health. This study aimed to investigate whether pre-treatment baseline left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) values were associated with symptom improvement after metoprolol therapy for children and adolescents with POTS. METHODS This retrospective study evaluated 51 children and adolescents with POTS who received metoprolol therapy at the Peking University First Hospital between November 2010 and July 2019. All patients had completed a standing test or basic head-up tilt test and cardiac echocardiography before treatment. Treatment response was evaluated 3 months after starting metoprolol therapy. The pre-treatment baseline LVEF and LVFS values were evaluated for correlations with decreases in the symptom score after treatment (ΔSS). Multivariable analysis was performed using factors with a P value of <0.100 in the univariate analyses and the demographic characteristics. RESULTS A comparison of responders and non-responders revealed no significant differences in demographic, hemodynamic characteristics, and urine specific gravity (all P > 0.050). However, responders had significantly higher baseline LVEF (71.09% ± 4.44% vs. 67.17% ± 4.88%, t = -2.789, P = 0.008) and LVFS values (40.00 [38.00, 42.00]% vs. 36.79% ± 4.11%, Z = -2.542, P = 0.010) than the non-responders. The baseline LVEF and LVFS were positively correlated with ΔSS (r = 0.378, P = 0.006; r = 0.363, P = 0.009), respectively. Logistic regression analysis revealed that LVEF was independently associated with the response to metoprolol therapy in children and adolescents with POTS (odds ratio: 1.201, 95% confidence interval: 1.039-1.387, P = 0.013). CONCLUSIONS Pre-treatment baseline LVEF was associated with symptom improvement after metoprolol treatment for children and adolescents with POTS.
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Affiliation(s)
- Yuan-Yuan Wang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Zhen-Hui Han
- Department of Pediatrics, Children's Hospital of Kaifeng, Henan 475000, China
| | - Yu-Li Wang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Ying Liao
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Chun-Yu Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Ping Liu
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Chao-Shu Tang
- Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing 100191, China
- Department of Physiology and Pathophysiology, Health Science Centre, Peking University, Beijing 100191, China
| | - Jun-Bao Du
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
- Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing 100191, China
| | - Hong-Fang Jin
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Ya-Qian Huang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
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15
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Vernino S, Bourne KM, Stiles LE, Grubb BP, Fedorowski A, Stewart JM, Arnold AC, Pace LA, Axelsson J, Boris JR, Moak JP, Goodman BP, Chémali KR, Chung TH, Goldstein DS, Diedrich A, Miglis MG, Cortez MM, Miller AJ, Freeman R, Biaggioni I, Rowe PC, Sheldon RS, Shibao CA, Systrom DM, Cook GA, Doherty TA, Abdallah HI, Darbari A, Raj SR. Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting - Part 1. Auton Neurosci 2021; 235:102828. [PMID: 34144933 DOI: 10.1016/j.autneu.2021.102828] [Citation(s) in RCA: 114] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/10/2021] [Accepted: 05/30/2021] [Indexed: 12/13/2022]
Abstract
Postural orthostatic tachycardia syndrome (POTS) is a chronic and often disabling disorder characterized by orthostatic intolerance with excessive heart rate increase without hypotension during upright posture. Patients often experience a constellation of other typical symptoms including fatigue, exercise intolerance and gastrointestinal distress. A typical patient with POTS is a female of child-bearing age, who often first displays symptoms in adolescence. The onset of POTS may be precipitated by immunological stressors such as a viral infection. A variety of pathophysiologies are involved in the abnormal postural tachycardia response; however, the pathophysiology of the syndrome is incompletely understood and undoubtedly multifaceted. Clinicians and researchers focused on POTS convened at the National Institutes of Health in July 2019 to discuss the current state of understanding of the pathophysiology of POTS and to identify priorities for POTS research. This article, the first of two articles summarizing the information discussed at this meeting, summarizes the current understanding of this disorder and best practices for clinical care. The evaluation of a patient with suspected POTS should seek to establish the diagnosis, identify co-morbid conditions, and exclude conditions that could cause or mimic the syndrome. Once diagnosed, management typically begins with patient education and non-pharmacologic treatment options. Various medications are often used to address specific symptoms, but there are currently no FDA-approved medications for the treatment of POTS, and evidence for many of the medications used to treat POTS is not robust.
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Affiliation(s)
- Steven Vernino
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Kate M Bourne
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Lauren E Stiles
- Department of Neurology, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA; Dysautonomia International, East Moriches, NY, USA
| | - Blair P Grubb
- Division of Cardiology, Department of Medicine, The University of Toledo Medical Center, USA
| | - Artur Fedorowski
- Department of Clinical Sciences, Lund University, Malmö, Sweden; Department of Cardiology, Skåne University Hospital, Malmö, Sweden
| | - Julian M Stewart
- Center for Hypotension, Departments of Pediatrics and Physiology, New York Medical College, Valhalla, NY, USA
| | - Amy C Arnold
- Department of Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, PA, USA; Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Laura A Pace
- Center for Genomic Medicine and Department of Pediatrics, Division of Medical Genetics and Genomics, University of Utah, Salt Lake City, UT, USA
| | - Jonas Axelsson
- Department of Clinical Immunology, Karolinska University Hospital, Stockholm, Sweden
| | | | - Jeffrey P Moak
- Department of Pediatrics, George Washington Univeristy School of Medicine and Health Sciences, Washington, DC, USA
| | - Brent P Goodman
- Neuromuscular Division, Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA
| | - Kamal R Chémali
- Department of Neurology, Eastern Virginia Medical School, Division of Neurology, Neuromuscular and Autonomic Center, Sentara Healthcare, Norfolk, VA, USA
| | - Tae H Chung
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David S Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Andre Diedrich
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine and Biomedical Engineering, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mitchell G Miglis
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Melissa M Cortez
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Amanda J Miller
- Department of Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Roy Freeman
- Department of Neurology, Harvard Medical School, Boston, MA, USA; Center for Autonomic and Peripheral Nerve Disorders, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Italo Biaggioni
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Departments of Medicine and Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Peter C Rowe
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert S Sheldon
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Cyndya A Shibao
- Autonomic Dysfunction Center, Division of Clinical Pharmacology, Departments of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - David M Systrom
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Glen A Cook
- Department of Neurology, Uniformed Services University, Bethesda, MD, USA
| | - Taylor A Doherty
- Division of Rheumatology, Allergy, and Immunology, Department of Medicine, University of California at San Diego, La Jolla, CA, USA
| | | | - Anil Darbari
- Pediatric Gastroenterology, Children's National Hospital, Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Satish R Raj
- Department of Cardiac Sciences, Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Autonomic Dysfunction Center, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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16
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Żyliński M, Niewiadomski W, Cybulski G, Gąsiorowska A. Device for Controlling Stimulus Self-Application During Autonomic Nervous System Tests. MEDICAL DEVICES-EVIDENCE AND RESEARCH 2021; 14:165-172. [PMID: 34104008 PMCID: PMC8179790 DOI: 10.2147/mder.s300384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 04/29/2021] [Indexed: 11/23/2022] Open
Abstract
Assessment of autonomic nervous system (ANS) functioning may be performed non-invasively using autonomic tests which are based on evaluation of response of cardiovascular system to the applied stimuli, such as increased air pressure during Valsalva maneuver, skeletal muscle contraction during static handgrip or deep slow breathing. The cardiovascular response depends, besides ANS reaction and test protocol, also on the way stimulus is self-applied by the test subject. We present a versatile device for controlling stimulus self-application during three ANS tests: Valsalva maneuver, static handgrip, and deep breathing. It integrates two different gauges and a pace setter for breathing into one device. The core of the device is a linear LED display which, using green, yellow, and red diodes, informs the subject about the correctness of self-application of respective stimulus. The settings of the device can be adjusted to the needs of the protocol chosen. The device can record the duration of mouth air pressure or the force produced by the subject during ANS tests, which assures correctness of the tests, thus allowing to track individual variability changes in the response to the test. The device was verified during ANS tests and its use was intuitive for patients, reducing the time needed for training before tests and decreasing the effort of the physician.
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Affiliation(s)
- Marek Żyliński
- Institute of Metrology and Biomedical Engineering, Faculty of Mechatronics, Warsaw University of Technology, Warsaw, Poland
| | - Wiktor Niewiadomski
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Gerard Cybulski
- Institute of Metrology and Biomedical Engineering, Faculty of Mechatronics, Warsaw University of Technology, Warsaw, Poland
| | - Anna Gąsiorowska
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
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17
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Simonyan MA, Borovkova EI, Ishbulatov YM, Skazkina VV, Karavaev AS, Shvartz VA, Kiselev AR. Gender-related specificities of photoplethysmogram spectral assessment dynamics in healthy subjects during the passive tilt test. RUSSIAN OPEN MEDICAL JOURNAL 2021. [DOI: 10.15275/rusomj.2021.0115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The goal of our study was to investigate gender-related specificities of photoplethysmogram (PPG) spectral assessment dynamics in healthy individuals during the passive tilt test.
Material and Methods — The study involved 38 men (33±7 years old) and 15 women (27±8 years old). The PPG signal was recorded for 10 minutes in the horizontal and vertical positions of the human body (passive tilt test). The following spectral parameters of PPG were calculated: HF%, LF%, and LF/HF.
Results — In the horizontal body position, men had significantly higher values of the LF% index. In the course of the passive tilt test, an increase in HF% was observed by almost 1.5 times in men and by more than 5 times in women. Significant differences in the values of vegetative indicators were achieved: in women, HF% values exceeded those in men, while LF% values were noticeably lower.
Conclusion — Men displayed signs (assessed by LF%) of augmented sympathetic activity, relative to women, at all stages of their passive tilt test. During the transition from the horizontal to the vertical position, a significant increase in respiratory influences (assessed by HF%) on PPG signal components was established, which was more pronounced in women.
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Isaacson SH, Dashtipour K, Mehdirad AA, Peltier AC. Management Strategies for Comorbid Supine Hypertension in Patients with Neurogenic Orthostatic Hypotension. Curr Neurol Neurosci Rep 2021; 21:18. [PMID: 33687577 PMCID: PMC7943503 DOI: 10.1007/s11910-021-01104-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW In autonomic failure, neurogenic orthostatic hypotension (nOH) and neurogenic supine hypertension (nSH) are interrelated conditions characterized by postural blood pressure (BP) dysregulation. nOH results in a sustained BP drop upon standing, which can lead to symptoms that include lightheadedness, orthostatic dizziness, presyncope, and syncope. nSH is characterized by elevated BP when supine and, although often asymptomatic, may increase long-term cardiovascular and cerebrovascular risk. This article reviews the pathophysiology and clinical characteristics of nOH and nSH, and describes the management of patients with both nOH and nSH. RECENT FINDINGS Pressor medications required to treat the symptoms of nOH also increase the risk of nSH. Because nOH and nSH are hemodynamically opposed, therapies to treat one condition may exacerbate the other. The management of patients with nOH who also have nSH can be challenging and requires an individualized approach to balance the short- and long-term risks associated with these conditions. Approaches to manage neurogenic BP dysregulation include nonpharmacologic approaches and pharmacologic treatments. A stepwise treatment approach is presented to help guide neurologists in managing patients with both nOH and nSH.
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Affiliation(s)
- Stuart H Isaacson
- Parkinson's Disease and Movement Disorders Center of Boca Raton, 951 NW 13th Street, Bldg. 5-E, Boca Raton, FL, USA.
| | - Khashayar Dashtipour
- Division of Movement Disorders, Department of Neurology, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Ali A Mehdirad
- Wright State University, Dayton VA Medical Center, Dayton, OH, USA
| | - Amanda C Peltier
- Department of Neurology and Medicine, Vanderbilt University, Nashville, TN, USA
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Wang YY, Du JB, Jin HF. Differential diagnosis of vasovagal syncope and postural tachycardia syndrome in children. World J Pediatr 2020; 16:549-552. [PMID: 32020440 DOI: 10.1007/s12519-019-00333-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 12/30/2019] [Indexed: 01/01/2023]
Affiliation(s)
- Yuan-Yuan Wang
- Department of Pediatrics, Peking University First Hospital, No. 1, Xi'an-men Street, West District, Beijing, 100034, China
| | - Jun-Bao Du
- Department of Pediatrics, Peking University First Hospital, No. 1, Xi'an-men Street, West District, Beijing, 100034, China.,Key Lab of Molecular Cardiovascular Sciences, The Ministry of Education, Beijing, 100191, China
| | - Hong-Fang Jin
- Department of Pediatrics, Peking University First Hospital, No. 1, Xi'an-men Street, West District, Beijing, 100034, China.
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20
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Phillips Z, Kim JB, Paik SH, Kang SY, Jeon NJ, Kim BM, Kim BJ. Regional analysis of cerebral hemodynamic changes during the head-up tilt test in Parkinson's disease patients with orthostatic intolerance. NEUROPHOTONICS 2020; 7:045006. [PMID: 33163544 PMCID: PMC7595744 DOI: 10.1117/1.nph.7.4.045006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 10/16/2020] [Indexed: 06/11/2023]
Abstract
Significance: Cerebral oxygenation changes in the superior, middle, and medial gyri were used to elucidate spatial impairments of autonomic hemodynamic recovery during the head-up tilt table test (HUTT) in Parkinson's disease (PD) patients with orthostatic intolerance (OI) symptoms. Aim: To analyze dynamic oxygenation changes during the HUTT and classify PD patients with OI symptoms using clinical and oxygenation features. Approach: Thirty-nine PD patients with OI symptoms [10: orthostatic hypotension (PD-OH); 29: normal HUTT results (PD-NOR)] and seven healthy controls (HCs) were recruited. Prefrontal oxyhemoglobin (HbO) changes during the HUTT were reconstructed with diffuse optical tomography and segmented using the automated anatomical labeling system. Decision trees were used for classification. Results: HCs and PD-NOR patients with positive rates of HbO change (PD-POS) showed the greatest HbO recovery in the superior frontal gyrus (SFG) during tilt. PD-OH and PD-NOR patients with negative rates of HbO change (PD-NEG) showed asymmetric reoxygenation. The classification accuracy was 89.4% for PD-POS versus PD-NEG, 71% for PD-NOR versus PD-OH, and 55.8% for PD-POS versus PD-NEG versus PD-OH. The oxygenation features were more discriminative than the clinical features. Conclusions: PD-OH showed decreased right SFG function, which may be associated with impaired compensatory autonomic responses to orthostatic stress.
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Affiliation(s)
- Zephaniah Phillips
- Korea University, Department of Bio-Convergence Engineering, Seoul, Republic of Korea
| | - Jung Bin Kim
- Korea University Anam Hospital, Department of Neurology, Seoul, Republic of Korea
| | - Seung-Ho Paik
- Korea University, Department of Bio-Convergence Engineering, Seoul, Republic of Korea
- KLIEN Inc., Seoul Biohub, Seoul, Republic of Korea
| | - Shin-Young Kang
- Korea University, Department of Bio-Convergence Engineering, Seoul, Republic of Korea
| | - Nam-Joon Jeon
- Korea University Anam Hospital, Neurophysiology Laboratory, Seoul, Republic of Korea
| | - Beop-Min Kim
- Korea University, Department of Bio-Convergence Engineering, Seoul, Republic of Korea
| | - Byung-Jo Kim
- Korea University Anam Hospital, Department of Neurology, Seoul, Republic of Korea
- Korea University Anam Hospital, Brain Convergence Research Center, Seoul, Republic of Korea
- Korea University, BK21 FOUR Program in Learning Health Systems, Seoul, Republic of Korea
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21
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Li S, Shi Y, Yao X, Wang X, Shen L, Rao Z, Yuan J, Liu Y, Zhou Z, Zhang Z, Liu F, Han S, Geng J, Yang H, Cheng L. Conversion of Astrocytes and Fibroblasts into Functional Noradrenergic Neurons. Cell Rep 2020; 28:682-697.e7. [PMID: 31315047 DOI: 10.1016/j.celrep.2019.06.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/25/2019] [Accepted: 06/12/2019] [Indexed: 11/18/2022] Open
Abstract
Dysfunction of noradrenergic (NA) neurons is associated with a number of neuronal disorders. Diverse neuronal subtypes can be generated by direct reprogramming. However, it is still unknown how to convert non-neuronal cells into NA neurons. Here, we show that seven transcription factors (TFs) (Ascl1, Phox2b, AP-2α, Gata3, Hand2, Nurr1, and Phox2a) are able to convert astrocytes and fibroblasts into induced NA (iNA) neurons. These iNA neurons express the genes required for the biosynthesis, release, and re-uptake of noradrenaline. Moreover, iNA neurons fire action potentials, receive synaptic inputs, and control the beating rate of co-cultured ventricular myocytes. Furthermore, iNA neurons survive and integrate into neural circuits after transplantation. Last, human fibroblasts can be converted into functional iNA neurons as well. Together, iNA neurons are generated by direct reprogramming, and they could be potentially useful for disease modeling and cell-based therapies.
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Affiliation(s)
- Sanlan Li
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuhan Shi
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuan Yao
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xing Wang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Libing Shen
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhiping Rao
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiacheng Yuan
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yueguang Liu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhenning Zhou
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ziheng Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Fei Liu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Su'e Han
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junlan Geng
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Hui Yang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Leping Cheng
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
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22
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Chen G, Du J, Jin H, Huang Y. Postural Tachycardia Syndrome in Children and Adolescents: Pathophysiology and Clinical Management. Front Pediatr 2020; 8:474. [PMID: 32974246 PMCID: PMC7468430 DOI: 10.3389/fped.2020.00474] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 07/06/2020] [Indexed: 12/21/2022] Open
Abstract
Postural tachycardia syndrome (POTS), characterized by chronic (≥6 months) orthostatic intolerance symptoms with a sustained and excessive heart rate increase while standing without postural hypotension, is common in children and adolescents. Despite the unclear pathogenesis of POTS, the present opinion is that POTS is a heterogeneous and multifactorial disorder that includes altered central blood volume, abnormal autonomic reflexes, "hyperadrenergic" status, damaged skeletal muscle pump activity, abnormal local vascular tension and vasoactive factor release, mast cell activation, iron insufficiency, and autoimmune dysfunction. A number of pediatric POTS patients are affected by more than one of these pathophysiological mechanisms. Therefore, individualized treatment strategies are initiated in the management of POTS, including basal non-pharmacological approaches (e.g., health education, the avoidance of triggers, exercise, or supplementation with water and salt) and special pharmacological therapies (e.g., oral rehydration salts, midodrine hydrochloride, and metoprolol). As such, the recent progress in the pathogenesis, management strategies, and therapeutic response predictors of pediatric POTS are reviewed here.
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Affiliation(s)
- Guozhen Chen
- Department of Pediatrics, Peking University First Hospital, Beijing, China
- Department of Pediatrics, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China
- Research Unit of Clinical Diagnosis and Treatment of Pediatric Syncope and Cardiovascular Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Junbao Du
- Department of Pediatrics, Peking University First Hospital, Beijing, China
- Key Laboratory of Molecular Cardiovascular Science, The Ministry of Education, Beijing, China
| | - Hongfang Jin
- Department of Pediatrics, Peking University First Hospital, Beijing, China
- Research Unit of Clinical Diagnosis and Treatment of Pediatric Syncope and Cardiovascular Diseases, Chinese Academy of Medical Sciences, Beijing, China
| | - Yaqian Huang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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23
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Kim HA, Bisdorff A, Bronstein AM, Lempert T, Rossi-Izquierdo M, Staab JP, Strupp M, Kim JS. Hemodynamic orthostatic dizziness/vertigo: Diagnostic criteria. J Vestib Res 2020; 29:45-56. [PMID: 30883381 PMCID: PMC9249281 DOI: 10.3233/ves-190655] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 02/25/2019] [Indexed: 11/15/2022]
Abstract
This paper presents the diagnostic criteria for hemodynamic orthostatic dizziness/vertigo to be included in the International Classification of Vestibular Disorders (ICVD). The aim of defining diagnostic criteria of hemodynamic orthostatic dizziness/vertigo is to help clinicians to understand the terminology related to orthostatic dizziness/vertigo and to distinguish orthostatic dizziness/vertigo due to global brain hypoperfusion from that caused by other etiologies. Diagnosis of hemodynamic orthostatic dizziness/vertigo requires: A) five or more episodes of dizziness, unsteadiness or vertigo triggered by arising or present during upright position, which subsides by sitting or lying down; B) orthostatic hypotension, postural tachycardia syndrome or syncope documented on standing or during head-up tilt test; and C) not better accounted for by another disease or disorder. Probable hemodynamic orthostatic dizziness/vertigo is defined as follows: A) five or more episodes of dizziness, unsteadiness or vertigo triggered by arising or present during upright position, which subsides by sitting or lying down; B) at least one of the following accompanying symptoms: generalized weakness/tiredness, difficulty in thinking/concentrating, blurred vision, and tachycardia/palpitations; and C) not better accounted for by another disease or disorder. These diagnostic criteria have been derived by expert consensus from an extensive review of 90 years of research on hemodynamic orthostatic dizziness/vertigo, postural hypotension or tachycardia, and autonomic dizziness. Measurements of orthostatic blood pressure and heart rate are important for the screening and documentation of orthostatic hypotension or postural tachycardia syndrome to establish the diagnosis of hemodynamic orthostatic dizziness/vertigo.
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Affiliation(s)
- Hyun Ah Kim
- Department of Neurology, Keimyung University Dongsan Hospital, Daegu, South Korea
| | - Alexandre Bisdorff
- Department of Neurology, Centre Hospitalier Emile Mayrisch, Esch-sur-Alzette, Luxembourg
| | - Adolfo M. Bronstein
- Department of Neuro-otology, Division of Brain Sciences, Imperial College London, Charing Cross Hospital Campus, London, UK
| | - Thomas Lempert
- Department of Neurology, Schlosspark-Klinik, Berlin, Germany
| | | | - Jeffrey P. Staab
- Departments of Psychiatry and Psychology and Otorhinolaryngology – Head and Neck Surgery, Mayo Clinic, Rochester, MN, USA
| | - Michael Strupp
- Department of Neurology and German Center for Vertigo and Balance Disorders, Ludwig Maximilians University, Munich, Germany
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, Dizziness Center, Seoul National University Bundang Hospital, Seongnam, South Korea
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24
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Borovik AS, Orlova EA, Tomilovskaya ES, Tarasova OS, Vinogradova OL. Phase Coupling Between Baroreflex Oscillations of Blood Pressure and Heart Rate Changes in 21-Day Dry Immersion. Front Physiol 2020; 11:455. [PMID: 32508675 PMCID: PMC7253653 DOI: 10.3389/fphys.2020.00455] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/09/2020] [Indexed: 11/13/2022] Open
Abstract
Introduction Dry immersion (DI) is a ground-based experimental model which reproduces the effects of microgravity on the cardiovascular system and, therefore, can be used to study the mechanisms of post-flight orthostatic intolerance in cosmonauts. However, the effects of long-duration DI on cardiovascular system have not been studied yet. The aim of this work was to study the effects of 21-day DI on systemic hemodynamics and its baroreflex control at rest and during head-up tilt test (HUTT). Methods Ten healthy young men were exposed to DI for 21 days. The day before, on the 7th, 14th, and 19th day of DI, as well as on the 1st and 5th days of recovery they were subjected to HUTT: 15 min in supine position and then 15 min of orthostasis (60°). ECG, arterial pressure, stroke volume and respiration rate were continuously recorded during the test. Phase synchronization index (PSI) of beat-to-beat mean arterial pressure (MAP) and heart rate (HR) in the frequency band of baroreflex waves (∼0.1 Hz) was used as a quantitative measure of baroreflex activity. Results During DI, strong tachycardia and the reduction of stroke volume were observed both in supine position and during HUTT, these indicators did not recover on post-immersion day 5. In contrast, systolic arterial pressure and MAP decreased during HUTT on 14th day of DI, but then restored to pre-immersion values. Before DI and on day 5 of recovery, a transition from supine position to orthostasis was accompanied by an increase in PSI at the baroreflex frequency. However, PSI did not change in HUTT performed during DI and on post-immersion day 1. The amplitude of MAP oscillations at this frequency were increased by HUTT at all time points, while an increase of respective HR oscillations was absent during DI. Conclusion 21-day DI drastically changed the hemodynamic response to HUTT, while its effect on blood pressure was reduced between days 14 and 19, which speaks in favor of the adaptation to the conditions of DI. The lack of increase in phase synchronization of baroreflex MAP and HR oscillations during HUTT indicates disorders of baroreflex cardiac control during DI.
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Affiliation(s)
- Anatoly S Borovik
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Evgeniya A Orlova
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Elena S Tomilovskaya
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Olga S Tarasova
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia.,Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Olga L Vinogradova
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia.,Faculty of Basic Medicine, M.V. Lomonosov Moscow State University, Moscow, Russia
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25
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The triad of orthostatic hypotension, blood pressure variability, and arterial stiffness: a new syndrome? J Hypertens 2020; 38:1031-1032. [PMID: 32371791 DOI: 10.1097/hjh.0000000000002411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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26
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Effects of Cardiac Sympathetic Neurodegeneration and PPAR γ Activation on Rhesus Macaque Whole Blood miRNA and mRNA Expression Profiles. BIOMED RESEARCH INTERNATIONAL 2020; 2020:9426204. [PMID: 32462037 PMCID: PMC7212295 DOI: 10.1155/2020/9426204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 03/13/2020] [Accepted: 04/03/2020] [Indexed: 02/02/2023]
Abstract
Degeneration of sympathetic innervation of the heart occurs in numerous diseases, including diabetes, idiopathic REM sleep disorder, and Parkinson's disease (PD). In PD, cardiac sympathetic denervation occurs in 80-90% of patients and can begin before the onset of motor symptoms. Today, there are no disease-modifying therapies for cardiac sympathetic neurodegeneration, and biomarkers are limited to radioimaging techniques. Analysis of expression levels of coding mRNA and noncoding RNAs, such as microRNAs (miRNAs), can uncover pathways involved in disease, leading to the discovery of biomarkers, pathological mechanisms, and potential drug targets. Whole blood in particular is a clinically relevant source of biomarkers, as blood sampling is inexpensive and simple to perform. Our research group has previously developed a nonhuman primate model of cardiac sympathetic denervation by intravenous administration of the catecholaminergic neurotoxin 6-hydroxydopamine (6-OHDA). In this rhesus macaque (Macaca mulatta) model, imaging with positron emission tomography showed that oral administration of the peroxisome proliferator-activated receptor gamma (PPARγ) agonist pioglitazone (n = 5; 5 mg/kg daily) significantly decreased cardiac inflammation and oxidative stress compared to placebo (n = 5). Here, we report our analysis of miRNA and mRNA expression levels over time in the whole blood of these monkeys. Differential expression of three miRNAs was induced by 6-OHDA (mml-miR-16-2-3p, mml-miR-133d-3p, and mml-miR-1262-5p) and two miRNAs by pioglitazone (mml-miR-204-5p and mml-miR-146b-5p) at 12 weeks posttoxin, while expression of mRNAs involved in inflammatory cytokines and receptors was not significantly affected. Overall, this study contributes to the characterization of rhesus coding and noncoding RNA profiles in normal and disease-like conditions, which may facilitate the identification and clinical translation of biomarkers of cardiac neurodegeneration and neuroprotection.
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27
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Geddes J, Mehlsen J, Olufsen MS. Characterization of Blood Pressure and Heart Rate Oscillations of POTS Patients via Uniform Phase Empirical Mode Decomposition. IEEE Trans Biomed Eng 2020; 67:3016-3025. [PMID: 32078525 DOI: 10.1109/tbme.2020.2974095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Postural Orthostatic Tachycardia Syndrome (POTS) is associated with the onset of tachycardia upon postural change. The current diagnosis involves the measurement of heart rate (HR) and blood pressure (BP) during head-up tilt (HUT) or active standing test. A positive diagnosis is made if HR changes with more than 30 bpm (40 bpm in patients aged 12-19 years), ignoring all of the BP and most of the HR signals. This study examines 0.1 Hz oscillations in systolic arterial blood pressure (SBP) and HR signals providing additional metrics characterizing the dynamics of the baroreflex. METHODS We analyze data from 28 control subjects and 28 POTS patients who underwent HUT. We extract beat-to-beat HR and SBP during a 10 min interval including 5 minutes of baseline and 5 minutes of HUT. We employ Uniform Phase Empirical Mode Decomposition (UPEMD) to extract 0.1 Hz stationary modes from both signals and use random forest machine learning and k-means clustering to analyze the outcomes. Results show that the amplitude of the 0.1 Hz oscillations is higher in POTS patients and that the phase response between the two signals is shorter (p < 0.005). CONCLUSION POTS is associated with an increase in the amplitude of SBP and HR 0.1 Hz oscillation and shortening of the phase between the two signals. SIGNIFICANCE The 0.1 Hz phase response and oscillation amplitude metrics provide new markers that can improve POTS diagnostic augmenting the existing diagnosis protocol only analyzing the change in HR.
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28
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Jacob G, Diedrich L, Sato K, Brychta RJ, Raj SR, Robertson D, Biaggioni I, Diedrich A. Vagal and Sympathetic Function in Neuropathic Postural Tachycardia Syndrome. Hypertension 2019; 73:1087-1096. [PMID: 30879357 DOI: 10.1161/hypertensionaha.118.11803] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The diagnosis of neuropathic postural tachycardia syndrome (POTS) requires research techniques not available clinically. We hypothesized that these patients will have impaired vagal and sympathetic cardiovascular control that can be characterized with clinical autonomic tests. We included 12 POTS patients with possible neuropathic subtype because of normal plasma norepinephrine and no increase in upright blood pressure. We compared them to 10 healthy subjects. We assessed hemodynamics, heart rate and blood pressure variability, baroreflex sensitivity, raw and integrated muscle sympathetic nerve activity, and blood volume. To understand the vagal/sympathetic control, we dissected the phase 2 of Valsalva maneuver (VM) into early (VM2e) and late (VM2l). POTS' upright heart rate increased 43±3 bpm. Patients had normal plasma volume but reduced red blood cell volume (1.29 L versus predicted normal values 1.58 L; P=0.02). Vagal indices of heart rate variability, HFRRI (430±130 versus 1680±900; P=0.04), PNN50, and root mean squared of successive differences were lower in POTS. Patients showed a decrease in vagal baroreflex sensitivity (VM2e; P=0.04). In POTS, integrated muscle sympathetic nerve activity was lower at rest (12±1.5 versus 20±2 burst/min; P=0.004) and raw muscle sympathetic nerve activity spike analysis showed blunted responses during VM2e, despite a greater drop in systolic blood pressure (34±5 in POTS and 14±6 mm Hg in controls; P=0.01). This cohort of POTS patients enriched for possible neuropathic subtype had lower resting muscle sympathetic nerve activity, impaired vagal cardiac control, and exaggerated drop in blood pressure in response to VM and a delay in the sympathetic cardiovascular responsiveness during hypotensive challenge.
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Affiliation(s)
- Giris Jacob
- From the Department of Medicine F & J. Recanati Autonomic Dysfunction Center, Tel Aviv "Sourasky" Medical Center and Sackler Faculty of Medicine, University of Tel Aviv, Israel (G.J.)
| | - Laura Diedrich
- US Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville (L.D.)
| | - Kyoko Sato
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN.,Department of Medicine, Tokyo Women's Medical University, Medical Center East, Japan (K.S.)
| | - Robert J Brychta
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (R.J.B.)
| | - Satish R Raj
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN
| | - David Robertson
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN.,Department of Neurology (D.R.), Vanderbilt University School of Medicine, Nashville, TN
| | - Italo Biaggioni
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN
| | - André Diedrich
- Division of Clinical Pharmacology, Department of Medicine, Autonomic Dysfunction Center (K.S., S.R.R., D.R., I.B., A.D.), Vanderbilt University School of Medicine, Nashville, TN.,Department of Biomedical Engineering (A.D.), Vanderbilt University School of Medicine, Nashville, TN
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Brenner IKM, Brown CA, Hains SJM, Tranmer J, Zelt DT, Brown PM. Low-Intensity Exercise Training Increases Heart Rate Variability in Patients With Peripheral Artery Disease. Biol Res Nurs 2019; 22:24-33. [PMID: 31684758 DOI: 10.1177/1099800419884642] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Patients with peripheral artery disease (PAD), consistent with others with atherosclerotic occlusive disorders, have autonomic dysfunction (as measured by low heart rate variability [HRV]) that predisposes them to sympathetically mediated cardiac arrhythmias and sudden death. Exercise therapy has been shown to increase HRV in patients with coronary artery disease by increasing parasympathetic modulation of heart rate. This study quantified the circulatory and autonomic effects of a progressive, 12-week home-based, low-intensity (pain-free walking) exercise program in PAD and intermittent claudication. Participants (N = 33, mean age 67.8 8.1 years) were randomly assigned to either a walking group (n = 18), whose members performed a structured, 12-week, progressive walking program 5 days/week for 12 weeks, or a comparison group (n = 15), whose members performed usual activities. Circulatory measures (heart rate, blood pressure, and rate pressure product) and autonomic measures (HRV) were obtained at the beginning (Week 1) and end (Week 12) of the study. Minimal change in circulatory measures occurred. However, spectral analysis of HRV revealed that autonomic function improved significantly in members of the walking group; specifically, there was an increase in parasympathetic and a decrease in sympathetic modulation. Members of the walking group also significantly increased maximal walking distance. These findings suggest that a structured, low-intensity, high-frequency walking program improves autonomic function by increasing HRV in patients with PAD.
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Affiliation(s)
| | | | - Sylvia J M Hains
- School of Nursing, Queen's University, Kingston, Ontario, Canada
| | - Joan Tranmer
- School of Nursing, Queen's University, Kingston, Ontario, Canada
| | - David T Zelt
- Division of Vascular Surgery, Queens University, Kingston, Ontario, Canada.,Kingston Health Sciences Centre, Kingston, Ontario, Canada
| | - Peter M Brown
- Division of Vascular Surgery, Queens University, Kingston, Ontario, Canada.,Kingston Health Sciences Centre, Kingston, Ontario, Canada
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Gholamrezaei A, Van Diest I, Aziz Q, Vlaeyen JWS, Van Oudenhove L. Influence of inspiratory threshold load on cardiovascular responses to controlled breathing at 0.1 Hz. Psychophysiology 2019; 56:e13447. [DOI: 10.1111/psyp.13447] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/05/2019] [Accepted: 07/06/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Ali Gholamrezaei
- Laboratory for Brain‐Gut Axis Studies (LaBGAS), Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing University of Leuven Leuven Belgium
- Health Psychology Research Group, Faculty of Psychology and Educational Sciences University of Leuven Leuven Belgium
| | - Ilse Van Diest
- Health Psychology Research Group, Faculty of Psychology and Educational Sciences University of Leuven Leuven Belgium
| | - Qasim Aziz
- Centre for Neuroscience and Trauma Blizard Institute, Wingate Institute of Neurogastroeneterology, Queen Mary University of London London UK
| | - Johan W. S. Vlaeyen
- Health Psychology Research Group, Faculty of Psychology and Educational Sciences University of Leuven Leuven Belgium
| | - Lukas Van Oudenhove
- Laboratory for Brain‐Gut Axis Studies (LaBGAS), Translational Research Center for Gastrointestinal Disorders (TARGID), Department of Chronic Diseases, Metabolism and Ageing University of Leuven Leuven Belgium
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Negulyaev VO, Tarasova OS, Tarasova NV, Lukoshkova EV, Vinogradova OL, Borovik AS. Phase synchronization of baroreflex oscillations of blood pressure and pulse interval in rats: the effects of cardiac autonomic blockade and gradual blood loss. Physiol Meas 2019; 40:054003. [PMID: 30884478 DOI: 10.1088/1361-6579/ab10d6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Phase synchronization of arterial pressure (AP) and pulse interval (PI) oscillations in the low-frequency band (around 0.4 Hz in rats) is governed by baroreflex activity. In long-term stationary data recordings, such synchronization can be estimated by the coherence. The phase synchronization index (PSI) can be used as well. The aim of this study was to correlate PSI and the coherence of AP and PI under stationary conditions and to estimate the informativity of PSI as a measure of baroreflex activity during transient processes. APPROACH AP and PI were recorded in conscious Wistar rats using femoral artery catheters. To study the hemodynamics during hemorrhage, blood was gradually withdrawn (20 ml × kg-1 over 30 min) through a catheter in the carotid artery. MAIN RESULTS PSI and coherence spectra calculated from 30-minute AP and PI recordings demonstrated distinct peaks at the frequency of 0.4 Hz; these indicators correlate well with each other (Pearson r = 0.920, p < 0.0001). Both PSI and coherence were markedly suppressed by vagal blockade (methylatropine) and tended to reduce after sympathetic blockade (atenolol). Importantly, PSI demonstrated dynamic alterations during gradual hemorrhage. During the initial approx. 10 min of hemorrhage, AP did not change but PI was noticeably shortened, and PSI increased, which indicates the activation of the baroreflex. With further blood loss, baroreflex influences were not enough to prevent blood pressure from falling, and under such conditions PSI decreased. SIGNIFICANCE PSI, like coherence, is an informative measure of baroreflex activity under stationary conditions. In addition, PSI permits us to follow the coupling between the baroreflex oscillations of AP and PI during transient processes, which strengthens its informative value.
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Affiliation(s)
- Vladimir O Negulyaev
- State Research Center of the Russian Federation-Institute for Biomedical Problems, Russian Academy of Sciences, Khoroshevskoe shosse 76A, 123007, Moscow, Russia. M V Lomonosov Moscow State University, Leninskie Gory 1, 119234, Moscow, Russia. Author to whom any correspondence should be addressed
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Abnormalities in autonomic function in obese boys at-risk for insulin resistance and obstructive sleep apnea. Pediatr Res 2019; 85:790-798. [PMID: 30420708 PMCID: PMC6494692 DOI: 10.1038/s41390-018-0226-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 10/13/2018] [Indexed: 01/02/2023]
Abstract
STUDY OBJECTIVES Current evidence in adults suggests that, independent of obesity, obstructive sleep apnea (OSA) can lead to autonomic dysfunction and impaired glucose metabolism, but these relationships are less clear in children. The purpose of this study was to investigate the associations among OSA, glucose metabolism, and daytime autonomic function in obese pediatric subjects. METHODS Twenty-three obese boys participated in: overnight polysomnography; a frequently sampled intravenous glucose tolerance test; and recordings of spontaneous cardiorespiratory data in both the supine (baseline) and standing (sympathetic stimulus) postures. RESULTS Baseline systolic blood pressure and reactivity of low-frequency heart rate variability to postural stress correlated with insulin resistance, increased fasting glucose, and reduced beta-cell function, but not OSA severity. Baroreflex sensitivity reactivity was reduced with sleep fragmentation, but only for subjects with low insulin sensitivity and/or low first-phase insulin response to glucose. CONCLUSIONS These findings suggest that vascular sympathetic activity impairment is more strongly affected by metabolic dysfunction than by OSA severity, while blunted vagal autonomic function associated with sleep fragmentation in OSA is enhanced when metabolic dysfunction is also present.
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Circadian hemodynamics in men and women with high blood pressure: dipper vs. nondipper and racial differences. J Hypertens 2019; 36:250-258. [PMID: 28902662 DOI: 10.1097/hjh.0000000000001533] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The 'nondipping' pattern of circadian blood pressure (BP) variation is an established independent predictor of adverse cardiovascular outcomes. Although this phenomenon has been widely studied, its underlying circadian hemodynamics of cardiac output and systemic vascular resistance (SVR) have not been well characterized. We evaluated the hypothesis that BP nondipping would be associated with a blunted night-time reduction in SVR in a biracial sample of 140 (63 African-American and 77 white) men and women with elevated clinic BP (130-159/85-99 mmHg). METHODS AND RESULTS Twenty-four-hour ambulatory hemodynamics were assessed using standard ambulatory BP monitoring coupled with synchronized ambulatory impedance cardiography. Using the criterion of less than 10% dip in SBP, there were 51 nondippers (SBP dip = 7.3 ± 2.6%) and 89 dippers (SBP dip = 15.5 ± 3.4%). There was minimal change in cardiac output from daytime to night-time in both dippers and nondippers. However, SVR decreased from daytime to night-time, but nondippers compared with dippers exhibited a significantly attenuated decrease in SVR from daytime to night-time (7.8 vs. 16.1%, P < 0.001). Relative to their white counterparts, African-Americans also exhibited blunted SBP dipping (10.9 vs. 14.6%, P < 0.001) as well as an attenuated decrease in SVR (10.8 vs. 15.6%, P < 0.001). CONCLUSION Overall, these findings indicate that blunted night-time BP dipping is associated with impairment of the systemic vasodilation that is characteristic of the night-time sleep period and is especially prominent among African-Americans. In the context of high BP, these findings suggest that nondipping may be a manifestation, or marker, of more advanced vascular disease.
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Chalacheva P, Kato RM, Shah P, Veluswamy S, Denton CC, Sunwoo J, Thuptimdang W, Wood JC, Detterich JA, Coates TD, Khoo MCK. Sickle Cell Disease Subjects Have a Distinct Abnormal Autonomic Phenotype Characterized by Peripheral Vasoconstriction With Blunted Cardiac Response to Head-Up Tilt. Front Physiol 2019; 10:381. [PMID: 31031633 PMCID: PMC6470196 DOI: 10.3389/fphys.2019.00381] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 03/19/2019] [Indexed: 12/26/2022] Open
Abstract
In sickle cell disease (SCD), prolonged capillary transit times, resulting from reduced peripheral blood flow, increase the likelihood of rigid red cells entrapment in the microvasculature, predisposing to vaso-occlusive crisis. Since changes in peripheral flow are mediated by the autonomic nervous system (ANS), we tested the hypothesis that the cardiac and peripheral vascular responses to head-up tilt (HUT) are abnormal in SCD. Heart rate, respiration, non-invasive continuous blood pressure and finger photoplethysmogram (PPG) were monitored before, during, and after HUT in SCD, anemic controls and healthy subjects. Percent increase in heart rate from baseline was used to quantify cardiac ANS response, while percent decrease in PPG amplitude represented degree of peripheral vasoconstriction. After employing cluster analysis to determine threshold levels, the HUT responses were classified into four phenotypes: (CP) increased heart rate and peripheral vasoconstriction; (C) increased heart rate only; (P) peripheral vasoconstriction only; and (ST) subthreshold cardiac and peripheral vascular responses. Multinomial logistic regression (MLR) was used to relate these phenotypic responses to various parameters representing blood properties and baseline cardiovascular activity. The most common phenotypic response, CP, was found in 82% of non-SCD subjects, including those with chronic anemia. In contrast, 70% of SCD subjects responded abnormally to HUT: C-phenotype = 22%, P-phenotype = 37%, or ST-phenotype = 11%. MLR revealed that the HUT phenotypes were significantly associated with baseline cardiac parasympathetic activity, baseline peripheral vascular variability, hemoglobin level and SCD diagnosis. Low parasympathetic activity at baseline dramatically increased the probability of belonging to the P-phenotype in SCD subjects, even after adjusting for hemoglobin level, suggesting a characteristic autonomic dysfunction that is independent of anemia. Further analysis using a mathematical model of heart rate variability revealed that the low parasympathetic activity in P-phenotype SCD subjects was due to impaired respiratory-cardiac coupling rather than reduced cardiac baroreflex sensitivity. By having strong peripheral vasoconstriction without compensatory cardiac responses, P-phenotype subjects may be at increased risk for vaso-occlusive crisis. The classification of autonomic phenotypes based on HUT response may have potential use for guiding therapeutic interventions to alleviate the risk of adverse outcomes in SCD.
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Affiliation(s)
- Patjanaporn Chalacheva
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Roberta M Kato
- Divisions of Pulmonology, Children's Hospital Los Angeles, Los Angeles, CA, United States
| | - Payal Shah
- Hematology Section, Children's Center for Cancer, Blood Disease and Bone Marrow Transplantation, Children's Hospital Los Angeles, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Saranya Veluswamy
- Hematology Section, Children's Center for Cancer, Blood Disease and Bone Marrow Transplantation, Children's Hospital Los Angeles, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Christopher C Denton
- Hematology Section, Children's Center for Cancer, Blood Disease and Bone Marrow Transplantation, Children's Hospital Los Angeles, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - John Sunwoo
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Wanwara Thuptimdang
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - John C Wood
- Divisions of Cardiology, Children's Hospital Los Angeles, Los Angeles, CA, United States
| | - Jon A Detterich
- Divisions of Cardiology, Children's Hospital Los Angeles, Los Angeles, CA, United States
| | - Thomas D Coates
- Hematology Section, Children's Center for Cancer, Blood Disease and Bone Marrow Transplantation, Children's Hospital Los Angeles, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Michael C K Khoo
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
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Assessment of Baroreflex Sensitivity Using Time-Frequency Analysis during Postural Change and Hypercapnia. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2019; 2019:4875231. [PMID: 30863454 PMCID: PMC6377966 DOI: 10.1155/2019/4875231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 12/16/2018] [Accepted: 01/06/2019] [Indexed: 01/09/2023]
Abstract
Baroreflex is a mechanism of short-term neural control responsible for maintaining stable levels of arterial blood pressure (ABP) in an ABP-heart rate negative feedback loop. Its function is assessed by baroreflex sensitivity (BRS)—a parameter which quantifies the relationship between changes in ABP and corresponding changes in heart rate (HR). The effect of postural change as well as the effect of changes in blood O2 and CO2 have been the focus of multiple previous studies on BRS. However, little is known about the influence of the combination of these two factors on dynamic baroreflex response. Furthermore, classical methods used for BRS assessment are based on the assumption of stationarity that may lead to unreliable results in the case of mostly nonstationary cardiovascular signals. Therefore, we aimed to investigate BRS during repeated transitions between squatting and standing in normal end-tidal CO2 (EtCO2) conditions (normocapnia) and conditions of progressively increasing EtCO2 with a decreasing level of O2 (hypercapnia with hypoxia) using joint time and frequency domain (TF) approach to BRS estimation that overcomes the limitation of classical methods. Noninvasive continuous measurements of ABP and EtCO2 were conducted in a group of 40 healthy young volunteers. The time course of BRS was estimated from TF representations of pulse interval variability and systolic pressure variability, their coherence, and phase spectra. The relationship between time-variant BRS and indices of ABP and HR was analyzed during postural change in normocapnia and hypercapnia with hypoxia. In normocapnia, observed trends in all measures were in accordance with previous studies, supporting the validity of presented TF method. Similar but slightly attenuated response to postural change was observed in hypercapnia with hypoxia. Our results show the merits of the nonstationary methods as a tool to study the cardiovascular system during short-term hemodynamic changes.
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Bhatt S, Northcott C, Wisialowski T, Li D, Steidl-Nichols J. Preclinical to Clinical Translation of Hemodynamic Effects in Cardiovascular Safety Pharmacology Studies. Toxicol Sci 2019; 169:272-279. [DOI: 10.1093/toxsci/kfz035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
- Siddhartha Bhatt
- Global Safety Pharmacology, Pfizer Worldwide Research and Development, Groton, Connecticut
| | - Carrie Northcott
- Global Safety Pharmacology, Pfizer Worldwide Research and Development, Groton, Connecticut
| | - Todd Wisialowski
- Global Safety Pharmacology, Pfizer Worldwide Research and Development, Groton, Connecticut
| | - Dingzhou Li
- Regulatory Strategy and Compliance, Pfizer Worldwide Research and Development, Groton, Connecticut
| | - Jill Steidl-Nichols
- Global Safety Pharmacology, Pfizer Worldwide Research and Development, Groton, Connecticut
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Miki K, Yoshimoto M. Exercise-Induced Modulation of Baroreflex Control of Sympathetic Nerve Activity. Front Neurosci 2018; 12:493. [PMID: 30083091 PMCID: PMC6064938 DOI: 10.3389/fnins.2018.00493] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/02/2018] [Indexed: 12/19/2022] Open
Abstract
Exercise modulates arterial pressure (AP) regulation over various time spans. AP increases at the onset of exercise and this increase is then sustained during exercise. Once exercise is stopped, AP is suppressed for up to an hour afterwards. Prolonged endurance training is associated with dysfunction of the sympathetic regulation of AP in response to posture changes (orthostatic intolerance). Baroreflex control of sympathetic nerve activity (SNA) has been extensively studied to understand the mechanisms underlying exercise-induced changes in AP. We have previously presented entire baroreflex AP-SNA curves during and after exercise, and during central volume expansion, obtained using direct measurements of renal sympathetic nerve activity (RSNA) in conscious animals. In this review, we describe the modulatory effects of exercise on baroreflex control of AP based on these entire AP-RSNA baroreflex curves. We suggest that both acute and chronic exercise can have modulatory effects on the entire baroreflex curve for SNA, and that these effects differ among time periods.
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Affiliation(s)
- Kenju Miki
- Department of Environmental Health, Life Science and Human Technology, Nara Women's University, Nara, Japan
| | - Misa Yoshimoto
- Department of Environmental Health, Life Science and Human Technology, Nara Women's University, Nara, Japan
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Liao Y, Xu WR, Li HX, Tang CS, Jin HF, Du JB. Plasma Neuropeptide Y Levels in Vasovagal Syncope in Children. Chin Med J (Engl) 2018; 130:2778-2784. [PMID: 29176136 PMCID: PMC5717855 DOI: 10.4103/0366-6999.219157] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background: Vasovagal syncope (VVS) is the most common cause of syncope in children. Neuropeptide Y (NPY) plays an important role in the regulation of blood pressure (BP), as well as myocardial contractility. This study aimed to explore the role of plasma NPY in VVS in children. Methods: Fifty-six children who were diagnosed with VVS (VVS group) using head-up tilt test (HUT) and 31 healthy children who were selected as controls (control group) were enrolled. Plasma NPY concentrations were detected. The independent t-test was used to compare the data of the VVS group with those of the control group. The changes in plasma NPY levels in the VVS group during the HUT, as well as hemodynamic parameters, such as heart rate (HR), BP, total peripheral vascular resistance (TPVR), and cardiac output (CO), were evaluated using the paired t-test. Furthermore, the correlations between plasma NPY levels and hemodynamic parameters were analyzed using bivariate correlation analysis. Results: The BP, HR, and plasma NPY (0.34 ± 0.12 pg/ml vs. 0.46 ± 0.13 pg/ml) levels in the supine position were statistically low in the VVS group compared to levels in the control group (all P < 0.05). Plasma NPY levels were positively correlated with the HR (Pearson, R = 0.395, P < 0.001) and diastolic BP (Pearson, R = 0.311, P = 0.003) when patients were in the supine position. When patients in the VVS group were in the supine position, elevated TPVR (4.6 ± 3.7 mmHg·min−1·L−1 vs. 2.5 ± 1.0 mmHg·min−1·L−1, respectively, P < 0.001; 1 mmHg = 0.133 kPa) and reduced CO (1.0 ± 0.7 L/min vs. 2.4 ± 1.3 L/min, respectively, P < 0.001) were observed in the positive-response period compared with baseline values. The plasma NPY levels were positively correlated with TPVR (Spearman, R = 0.294, P = 0.028) but negatively correlated with CO in the positive-response period during HUT (Spearman, R = −0.318, P = 0.017). Conclusions: Plasma NPY may contribute to the pathogenesis of VVS by increasing the TPVR and decreasing the CO during orthostatic regulation.
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Affiliation(s)
- Ying Liao
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Wen-Rui Xu
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Hong-Xia Li
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Chao-Shu Tang
- Department of Physiology and Pathophysiology, Health Sciences Centre, Peking University, Beijing 100083, China
| | - Hong-Fang Jin
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Jun-Bao Du
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
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Belanger P, Butler P, Butt M, Bhatt S, Foote S, Shelton D, Evans M, Arends R, Hurst S, Okerberg C, Cummings T, Potter D, Steidl-Nichols J, Zorbas M. From the Cover: Evaluation of the Effects of Tanezumab, a Monoclonal Antibody Against Nerve Growth Factor, on the Sympathetic Nervous System in Adult Cynomolgus Monkeys (Macaca fascicularis): A Stereologic, Histomorphologic, and Cardiofunctional Assessment. Toxicol Sci 2018; 158:319-333. [PMID: 28525647 PMCID: PMC5837719 DOI: 10.1093/toxsci/kfx089] [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] [Indexed: 02/07/2023] Open
Abstract
Tanezumab, a humanized monoclonal antibody against nerve growth factor is in development for treatment of chronic pain. Three nonclinical studies assessed effects of clinically relevant and supratherapeutic doses of tanezumab on the sympathetic nervous system (SNS) of adult nonhuman primates. Study 1 evaluated potential effects of subcutaneous (SC) tanezumab (1.2 mg/kg every 8 weeks [Q8W]) on SNS in cynomolgus monkeys for 3 or 6 months and reversibility or persistence of any effects through a nondosing/recovery period. Study 2 evaluated whether neuronal cell death occurs shortly after a single SC tanezumab injection (1.2 mg/kg). Assessments for these two studies included evaluations of superior cervical and cervicothoracic ganglia for neuronal cell death and morphology. Study 3 evaluated effects of SC tanezumab (1.2 mg/kg Q8W and 30 mg/kg/week) over 6 months on sympathetic control of cardiovascular function. Tanezumab exposure was associated with stereologic changes in sympathetic ganglia, including smaller ganglion volume, and smaller average neuron size/area beginning at 2 weeks and reaching maximal levels by 1 month with no further progression through 6 months. These changes were not associated with clinical signs, completely reversed upon tanezumab withdrawal, and were not considered adverse. Tanezumab had no adverse effects on sympathetic control of cardiovascular function. These data support the conclusion that tanezumab administration for up to 6 months has no adverse effects on SNS morphology or function and does not cause neuronal cell death in adult nonhuman primates.
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Affiliation(s)
| | | | - Mark Butt
- Tox Path Specialists, LLC, Frederick, Maryland 21701
| | | | | | | | - Mark Evans
- Pfizer, Inc., San Diego, California 92121
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Patel NM, Baker EAG, Wittman SR, Engstrom IC, Bourdages GH, McCall AA, Miller DM, Yates BJ. Cardiovascular adjustments during anticipated postural changes. Physiol Rep 2018; 6. [PMID: 29333722 PMCID: PMC5789654 DOI: 10.14814/phy2.13554] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/26/2017] [Accepted: 11/30/2017] [Indexed: 11/25/2022] Open
Abstract
It is well‐documented that feedforward cardiovascular responses occur at the onset of exercise, but it is unclear if such responses are associated with other types of movements. In this study, we tested the hypothesis that feedforward cardiovascular responses occur when a passive (imposed) 60° head‐up tilt is anticipated, such that changes in heart rate and carotid artery blood flow (CBF) commence prior to the onset of the rotation. A light cue preceded head‐up tilts by 10 sec, and heart rate and CBF were determined for 5‐sec time periods prior to and during tilts. Even after these stimuli were provided for thousands of trials spanning several months, no systematic changes in CBF and heart rate occurred prior to tilts, and variability in cardiovascular adjustments during tilt remained substantial over time. We also hypothesized that substitution of 20° for 60° tilts in a subset of trials would result in exaggerated cardiovascular responses (as animals expected 60° tilts), which were not observed. These data suggest that cardiovascular adjustments during passive changes in posture are mainly elicited by feedback mechanisms, and that anticipation of passive head‐up tilts does not diminish the likelihood that a decrease in carotid blood flow will occur during the movements.
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Affiliation(s)
- Neesirg M Patel
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Ethan A G Baker
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Samuel R Wittman
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Isaiah C Engstrom
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - George H Bourdages
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Andrew A McCall
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Derek M Miller
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Bill J Yates
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania
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41
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Simon E, Meuret AE, Ritz T. Sympathetic and parasympathetic cardiac responses to phobia-relevant and disgust-specific emotion provocation in blood-injection-injury phobia with and without fainting history. Psychophysiology 2017; 54:1512-1527. [DOI: 10.1111/psyp.12900] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 03/09/2017] [Accepted: 03/10/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Erica Simon
- Palo Alto Veterans Institute for Research; Palo Alto California USA
- National Center for PTSD-Dissemination and Training Division; Menlo Park California USA
| | - Alicia E. Meuret
- Department of Psychology; Southern Methodist University; Dallas Texas USA
| | - Thomas Ritz
- Department of Psychology; Southern Methodist University; Dallas Texas USA
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Sunwoo JS, Yang TW, Kim DY, Lim JA, Kim TJ, Byun JI, Moon J, Lee ST, Jung KH, Park KI, Jung KY, Kim M, Lee SK, Chu K. Association of blood pressure variability with orthostatic intolerance symptoms. PLoS One 2017; 12:e0179132. [PMID: 28591231 PMCID: PMC5462414 DOI: 10.1371/journal.pone.0179132] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 05/24/2017] [Indexed: 11/18/2022] Open
Abstract
The short-term blood pressure variability (BPV) reflects autonomic regulatory mechanisms. However, the influence of BPV in orthostatic intolerance (OI) is unknown. Herein, we assessed BPV profiles in patients with OI and determined their association with orthostatic symptoms. In this cross-sectional study, we prospectively enrolled 126 patients presenting with OI at the Seoul National University Hospital from December 2014 to August 2016. Among them, those with other neurological diseases (n = 8) and insufficient BP measurements (n = 15) were excluded. The degree of OI symptoms were measured using the self-administered orthostatic intolerance questionnaire (OIQ). All patients underwent ambulatory BP monitoring and we calculated the standard deviation and coefficient of variation as a measure of BPV. The mean age was 48.6 years and the average of the total OIQ score was 11.6. The severe OI group had higher BPV values than the mild group, although mean BP profiles did not differ significantly. Correlation analysis demonstrated that the orthostatic symptoms were positively correlated with diastolic BPV for the total and awake periods. Multiple linear regression analysis revealed that diastolic BPV (B = 0.46, p = 0.031) and current smoking (B = 4.687, p = 0.018) were independent factors for higher OI symptom scores after adjusting for covariates. The results of the current study demonstrated that a positive correlation exists between BPV and OI symptoms. Further studies are required to confirm the present findings and understand the neural mechanisms contributing to the excessive BPV in patients with OI.
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Affiliation(s)
- Jun-Sang Sunwoo
- Department of Neurology, Soonchunhyang University College of Medicine, Seoul, South Korea
| | - Tae-Won Yang
- Department of Neurology, Gyeongsang National University Changwon Hospital, Changwon, South Korea
| | - Do-Yong Kim
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
| | - Jung-Ah Lim
- Department of Neurology, National Center for Mental Health, An affiliate of the Ministry for Health & Welfare, Seoul, South Korea
| | - Tae-Joon Kim
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
| | - Jung-Ick Byun
- Department of Neurology, Kyung Hee University Hospital at Gangdong, Seoul, South Korea
| | - Jangsup Moon
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
| | - Soon-Tae Lee
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
| | - Keun-Hwa Jung
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
| | - Kyung-Il Park
- Department of Neurology, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, South Korea
| | - Ki-Young Jung
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
| | - Manho Kim
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
- Protein Metabolism Medical Research Center, Seoul National University College of Medicine, Seoul, South Korea
| | - Sang Kun Lee
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
- * E-mail: (SKL); (KC)
| | - Kon Chu
- Department of Neurology, Comprehensive Epilepsy Center, Seoul National University Hospital, Seoul, South Korea
- Program in Neuroscience, Seoul National University College of Medicine, Seoul, South Korea
- * E-mail: (SKL); (KC)
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43
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Medow MS, Merchant S, Suggs M, Terilli C, O’Donnell-Smith B, Stewart JM. Postural Heart Rate Changes in Young Patients With Vasovagal Syncope. Pediatrics 2017; 139:peds.2016-3189. [PMID: 28351846 PMCID: PMC5369676 DOI: 10.1542/peds.2016-3189] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2017] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Recurrent postural vasovagal syncope (VVS) is caused by transient cerebral hypoperfusion from episodic hypotension and bradycardia; diagnosis is made by medical history. VVS contrasts with postural tachycardia syndrome (POTS), defined by chronic daily symptoms of orthostatic intolerance with excessive upright tachycardia without hypotension. POTS has recently been conflated with VVS when excessive tachycardia is succeeded by hypotension during tilt testing. We hypothesize that excessive tachycardia preceding hypotension and bradycardia is part of the vasovagal response during tilt testing of patients with VVS. METHODS We prospectively performed head-up tilt (HUT) testing on patients with recurrent VVS (n = 47, 17.9 ± 1.1 y), who fainted at least 3 times within the last year, and control subjects (n = 15, 17.1 ± 1.0 y), from age and BMI-matched volunteers and measured blood pressure, heart rate (HR), cardiac output, total peripheral resistance, and end tidal carbon dioxide. RESULTS Baseline parameters were the same in both groups. HR (supine versus 5 and 10 minutes HUT) significantly increased in control (65 ± 2.6 vs 83 ± 3.6 vs 85 ± 3.7, P < .001) and patients with VVS (69 ± 1.6 vs 103 ± 2.3 vs 109 ± 2.4, P < .001). HUT in controls maximally increased HR by 20.3 ± 2.9 beats per minute; the increase in patients with VVS of 39.8 ± 2.1 beats per minute was significantly greater (P < .001). An increase in HR of ≥40 beats per minute by 5 and 10 minutes or before faint with HUT, occurred in 26% and 44% of patients with VVS, respectively, but not in controls. CONCLUSIONS Orthostasis in VVS is accompanied by large increases in HR that should not be construed as POTS.
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Affiliation(s)
- Marvin S. Medow
- Departments of Pediatrics, and,Physiology, New York Medical College, Valhalla, New York
| | | | | | | | | | - Julian M. Stewart
- Departments of Pediatrics, and,Physiology, New York Medical College, Valhalla, New York
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Nakatani T, Hashimoto T, Sutou I, Saito Y. Retention of finger blood flow against postural change as an indicator of successful sympathetic block in the upper limb. J Pain Res 2017; 10:475-479. [PMID: 28280382 PMCID: PMC5338961 DOI: 10.2147/jpr.s124627] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Sympathetic block in the upper limb has diagnostic, therapeutic and prognostic utility for disorders in the upper extremity that are associated with sympathetic disturbances. Increased skin temperature and decreased sweating are used to identify the adequacy of sympathetic block in the upper limb after stellate ganglion block (SGB). Baroreflexes elicited by postural change induce a reduction in peripheral blood flow by causing sympathetic vasoconstriction. We hypothesized that sympathetic block in the upper limb reduces the decrease in finger blood flow caused by baroreflexes stimulated by postural change from the supine to long sitting position. This study evaluated if sympathetic block of the upper limb affects the change in finger blood flow resulting from postural change. If change in finger blood flow would be kept against postural changes, it has a potential to be a new indicator of sympathetic blockade in the upper limb. Methods Subjects were adult patients who had a check-up at the Department of Pain Management in our university hospital over 2 years and 9 months from May 2012. We executed a total of 91 SGBs in nine patients (N=9), which included those requiring treatment for pain associated with herpes zoster in seven of the patients, tinnitus in one patient and upper limb pain in one patient. We checked for the following four signs after performing SGB: Horner’s sign, brachial nerve blockade, finger blood flow measured by a laser blood flow meter and skin temperature of the thumb measured by thermography, before and after SGB in the supine position and immediately after adopting the long sitting position. Results We executed a total of 91 SGBs in nine patients. Two SGBs were excluded from the analysis due to the absence of Horner’s sign. We divided 89 procedures into two groups according to elevation in skin temperature of the thumb: by over 1°C (sympathetic block group, n=62) and by <1°C (nonsympathetic block group, n=27). Finger blood flow decreased significantly just after a change in posture from the supine to long sitting position after SGB in both groups. In the sympathetic block group, the ratio of finger blood flow in the long sitting position/supine position with a change in posture significantly increased after SGB compared with before SGB (before SGB: range 0.09–0.94, median 0.53; after SGB: range 0.33–1.2, median 0.89, p<0.0001). Conclusion Our study shows that with sympathetic block in the upper limb, the ratio of finger blood flow significantly increases despite baroreflexes stimulated by postural change from the supine to long sitting position. Retention of finger blood flow against postural changes may be an indicator of sympathetic block in the upper limb after SGB or brachial plexus block.
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Affiliation(s)
- Toshihiko Nakatani
- Department of Palliative Care, Shimane University Faculty of Medicine, Izumo
| | | | - Ichiro Sutou
- Palliative Care Center, Shimane University Hospital, Izumo
| | - Yoji Saito
- Department of Anesthesiology, Shimane University Faculty of Medicine, Izumo, Japan
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45
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Stewart JM, Medow MS, Sutton R, Visintainer P, Jardine DL, Wieling W. Mechanisms of Vasovagal Syncope in the Young: Reduced Systemic Vascular Resistance Versus Reduced Cardiac Output. J Am Heart Assoc 2017; 6:e004417. [PMID: 28100453 PMCID: PMC5523632 DOI: 10.1161/jaha.116.004417] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 12/06/2016] [Indexed: 11/17/2022]
Abstract
BACKGROUND Syncope is a sudden transient loss of consciousness and postural tone caused by cerebral hypoperfusion. The most common form is vasovagal syncope (VVS). Presyncopal progressive early hypotension in older VVS patients is caused by reduced cardiac output (CO); younger patients have reduced systemic vascular resistance (SVR). Using a priori criteria for reduced CO (↓CO) and SVR (↓SVR), we studied 48 recurrent young fainters comparing subgroups of VVS with VVS-↓CO, VVS-↓SVR, and both VVS-↓CO&↓SVR. METHODS AND RESULTS Subjects were studied supine and during 70-degrere upright tilt with a Finometer to continuously measure blood pressure, CO, and SVR and impedance plethysmography to estimate thoracic, splanchnic, pelvic, and calf blood volumes, blood flows, and vascular resistances and electrocardiogram to measure heart rate and rhythm. Central blood volume was decreased in all VVS compared to control. VVS-↓CO was associated with decreased splanchnic blood flow and increased splanchnic blood pooling compared to control. Seventy-five percent of VVS patients had reduced SVR, including 23% who also had reduced CO. Many VVS-↓SVR increased CO during tilt, with no difference in splanchnic pooling, caused by significant increases in splanchnic blood flow and reduced splanchnic resistance. VVS-↓CO&↓SVR patients had splanchnic pooling comparable to VVS-↓CO patients, but SVR comparable to VVS-↓SVR. Splanchnic vasodilation was reduced, compared to VVS-↓SVR, and venomotor properties were similar to control. Combined splanchnic pooling and reduced SVR produced the earliest faints among the VVS groups. CONCLUSIONS Both ↓CO and ↓SVR occur in young VVS patients. ↓SVR is predominant in VVS and is caused by impaired splanchnic vasoconstriction.
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Affiliation(s)
- Julian M Stewart
- Departments of Pediatrics and Physiology, New York Medical College, Valhalla, NY
| | - Marvin S Medow
- Departments of Pediatrics and Physiology, New York Medical College, Valhalla, NY
| | - Richard Sutton
- The National Heart & Lung Institute, Imperial College, London, United Kingdom
| | - Paul Visintainer
- Baystate Medical Center, Tufts University School of Medicine, Springfield, MA
| | - David L Jardine
- Department of General Medicine, Christchurch Hospital, University of Otago, Christchurch, New Zealand
| | - Wouter Wieling
- Departments of Internal Medicine and of Clinical and Experimental Cardiology, Academic Medical Centre, University of Amsterdam, The Netherlands
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46
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Vermeiren Y, De Deyn PP. Targeting the norepinephrinergic system in Parkinson's disease and related disorders: The locus coeruleus story. Neurochem Int 2017; 102:22-32. [DOI: 10.1016/j.neuint.2016.11.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/10/2016] [Accepted: 11/23/2016] [Indexed: 01/12/2023]
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47
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Gutkin M, Stewart JM. Orthostatic Circulatory Disorders: From Nosology to Nuts and Bolts. Am J Hypertens 2016; 29:1009-19. [PMID: 27037712 PMCID: PMC4978226 DOI: 10.1093/ajh/hpw023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 11/27/2015] [Accepted: 02/12/2016] [Indexed: 12/17/2022] Open
Abstract
When patients complain of altered consciousness or discomfort in the upright posture, either relieved by recumbency or culminating in syncope, physicians may find themselves baffled. There is a wide variety of disorders that cause abnormal regulation of blood pressure and pulse rate in the upright posture. The aim of this focused review is 3-fold. First, to offer a classification (nosology) of these disorders; second, to illuminate the mechanisms that underlie them; and third, to assist the physician in the practical aspects of diagnosis of adult orthostatic hypotension, by extending clinical skills with readily available office technology.
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Affiliation(s)
- Michael Gutkin
- Hypertension Section, Saint Barnabas Medical Center, Livingston, New Jersey, USA;
| | - Julian M Stewart
- Center for Hypotension, New York Medical College, Valhalla, New Jersey, USA
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48
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Mlcek M, Belohlavek J, Huptych M, Boucek T, Belza T, Lacko S, Krupickova P, Hrachovina M, Popkova M, Neuzil P, Kittnar O. Head-up tilt rapidly compromises hemodynamics in healthy anesthetized swine. Physiol Res 2015; 64:S677-83. [PMID: 26674293 DOI: 10.33549/physiolres.933229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The aims were to explore the effect of head-up tilt (HUT) to 30 and 60 degrees on hemodynamics and tissue oxygenation in anesthetized healthy swine. The data serve as a reference for a study of resuscitation efficacy at HUT such as during transport. Nine healthy swine (49+/-4 kg) were anesthetized and multiple sensors including myocardial pressure-volume loops catheter, carotid flow probe, blood pressure catheters, near infrared spectroscopy (NIRS) tissue oximetry and mixed venous oximetry (SVO2) catheter were introduced and parameters continuously recorded. Experimental protocol consisted of baseline in supine position (15 min), 30 degrees HUT (15 min), recovery at supine position (15 min) and 60 degrees HUT (5 min). Vacuum mattress was used for body fixation during tilts. We found that 30 and 60 degrees inclination led to significant immediate reduction in hemodynamic and oximetry parameters. Mean arterial pressure (mm Hg) decreased from 98 at baseline to 53 and 39, respectively. Carotid blood flow dropped to 47 % and 22 % of baseline values, end diastolic volume to 49 % and 53 % and stroke volume to 47 % and 45 % of baseline. SVO2 and tissue oximetry decreased by 17 and 21 percentage points. The values are means. In conclusions, within minutes, both 30 and 60 degrees head-up tilting is poorly tolerated in anesthetized swine. Significant differences among individual animals exist.
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Affiliation(s)
- M Mlcek
- Institute of Physiology, First Faculty of Medicine, Charles University in Prague, Czech Republic.
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49
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Schmitt L, Regnard J, Millet GP. Monitoring Fatigue Status with HRV Measures in Elite Athletes: An Avenue Beyond RMSSD? Front Physiol 2015; 6:343. [PMID: 26635629 PMCID: PMC4652221 DOI: 10.3389/fphys.2015.00343] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/04/2015] [Indexed: 11/27/2022] Open
Abstract
Among the tools proposed to assess the athlete's “fatigue,” the analysis of heart rate variability (HRV) provides an indirect evaluation of the settings of autonomic control of heart activity. HRV analysis is performed through assessment of time-domain indices, the square root of the mean of the sum of the squares of differences between adjacent normal R-R intervals (RMSSD) measured during short (5 min) recordings in supine position upon awakening in the morning and particularly the logarithm of RMSSD (LnRMSSD) has been proposed as the most useful resting HRV indicator. However, if RMSSD can help the practitioner to identify a global “fatigue” level, it does not allow discriminating different types of fatigue. Recent results using spectral HRV analysis highlighted firstly that HRV profiles assessed in supine and standing positions are independent and complementary; and secondly that using these postural profiles allows the clustering of distinct sub-categories of “fatigue.” Since, cardiovascular control settings are different in standing and lying posture, using the HRV figures of both postures to cluster fatigue state embeds information on the dynamics of control responses. Such, HRV spectral analysis appears more sensitive and enlightening than time-domain HRV indices. The wealthier information provided by this spectral analysis should improve the monitoring of the adaptive training-recovery process in athletes.
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Affiliation(s)
- Laurent Schmitt
- Centre National de Ski Nordique et de Moyenne Montagne, Ecole Nationale des Sports de Montagne Prémanon, France ; Faculty of Biology and Medicine, Institute of Sport Sciences, University of Lausanne Lausanne, Switzerland
| | - Jacques Regnard
- Unité de Recherche EA3920, Marqueurs Pronostiques et Facteurs de Régulations des Pathologies Cardiaques et Vasculaires, Hôpital Universitaire de Besançon, Université de Franche-Comté Besançon, France
| | - Grégoire P Millet
- Faculty of Biology and Medicine, Institute of Sport Sciences, University of Lausanne Lausanne, Switzerland
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50
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Skoog J, Lindenberger M, Ekman M, Holmberg B, Zachrisson H, Länne T. Reduced venous compliance: an important determinant for orthostatic intolerance in women with vasovagal syncope. Am J Physiol Regul Integr Comp Physiol 2015; 310:R253-61. [PMID: 26561647 DOI: 10.1152/ajpregu.00362.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 11/09/2015] [Indexed: 11/22/2022]
Abstract
The influence of lower limb venous compliance on orthostatic vasovagal syncope (VVS) is uncertain. The most widespread technique to calculate venous compliance uses a nonphysiological quadratic regression equation. Our aim was therefore to construct a physiologically derived venous wall model (VWM) for calculation of calf venous compliance and to determine the effect of venous compliance on tolerance to maximal lower body negative pressure (LBNP). Venous occlusion plethysmography was used to study calf volume changes in 15 women with VVS (25.5 ± 1.3 yr of age) and 15 controls (22.8 ± 0.8 yr of age). The fit of the VWM and the regression equation to the experimentally induced pressure-volume curve was examined. Venous compliance was calculated as the derivative of the modeled pressure-volume relationship. Graded LBNP to presyncope was used to determine the LBNP tolerance index (LTI). The VWM displayed a better fit to the experimentally induced pressure-volume curve (P < 0.0001). Calf blood pooling was similar in the groups and was not correlated to the LTI (r = 0.204, P = 0.30). Venous compliance was significantly reduced at low venous pressures in women with VVS (P = 0.042) and correlated to the LTI (r = 0.459, P = 0.014) in the low pressure range. No correlation was found between venous compliance at high venous pressures and the LTI. In conclusion, the new VWM accurately adopted the curvilinear pressure-volume curve, providing a valid characterization of venous compliance. Reduced venous compliance at low venous pressures may adversely affect mobilization of peripheral venous blood to the central circulation during hypovolemic circulatory stress in women with VVS.
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Affiliation(s)
- Johan Skoog
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden;
| | - Marcus Lindenberger
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden; Department of Cardiology, Linköping University, Linköping, Sweden
| | | | - Bengt Holmberg
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden; Department of Clinical Physiology, Linköping University, Linköping, Sweden; and
| | - Helene Zachrisson
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden; Department of Clinical Physiology, Linköping University, Linköping, Sweden; and
| | - Toste Länne
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden; Department of Thoracic and Vascular Surgery, Linköping University, Linköping, Sweden
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