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Babcock MC, DuBose LE, Hildreth KL, Stauffer BL, Cornwell WK, Kohrt WM, Moreau KL. Age-associated reductions in cardiovagal baroreflex sensitivity are exaggerated in middle-aged and older men with low testosterone. J Appl Physiol (1985) 2022; 133:403-415. [PMID: 35771224 PMCID: PMC9359637 DOI: 10.1152/japplphysiol.00245.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aging is associated with reductions in cardiovagal baroreflex sensitivity (cBRS), which increases cardiovascular disease risk. Preclinical data indicate that low testosterone reduces cBRS. We determined whether low testosterone is associated with reduced cBRS in healthy men. METHODS Twenty-six men categorized as young (N=6; age=31±4 years; testosterone=535±60 ng/dL), middle-aged/older with normal (N=10; aged 56±3 years; testosterone=493±85 ng/dL), or low (N=10; age=57±6 years; testosterone=262±31 ng/dL) testosterone underwent recordings of beat-by-beat blood pressure and R-R interval during rest and two Valsalva maneuvers, and measures of carotid artery compliance. IL-6, CRP, oxidized LDL cholesterol and TAS were measured. RESULTS Middle-aged/older men had lower cBRS compared to young men (17.0±6.5 ms/mmHg; p=0.028); middle-age/older men with low testosterone had lower cBRS (5.5±3.2 ms/mmHg; p=0.039) compared to age-matched men with normal testosterone (10.7±4.0 ms/mmHg). No differences existed among groups during Phase II of the Valsalva maneuver; middle-aged/older men with low testosterone had reduced cBRS (4.7±2.6 ms/mmHg) compared to both young (12.8±2.8ms/mmHg; p<0.001) and middle-aged/older men with normal testosterone (8.6±4.4ms/mmHg; p=0.046) during Phase IV of the Valsalva maneuver. There were no differences in oxidized LDL, (p=0.882) or TAS across groups (p=0.633). IL-6 was significantly higher in middle-aged/older men with low testosterone compared to the other groups (p<0.05 for all) and inversely correlated with cBRS (r=-0.594, p=0.007). Middle-aged/older men had reduced carotid artery compliance compared to young, regardless of testosterone status (p<0.001). CONCLUSIONS These observations indicate that low testosterone in middle-aged/older men may contribute to a reduction in cBRS; increased inflammation may also contribute to a reduction in cBRS.
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Affiliation(s)
- Matthew C Babcock
- Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Veterans Affairs Eastern Colorado Geriatric Research, Educational and Clinical Center, Denver, CO, United States
| | - Lyndsey E DuBose
- Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Veterans Affairs Eastern Colorado Geriatric Research, Educational and Clinical Center, Denver, CO, United States
| | - Kerry L Hildreth
- Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Brian L Stauffer
- Division of Cardiology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Division of Cardiology, Denver Health Medical Center, Denver, CO, United States
| | - William K Cornwell
- Division of Cardiology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Wendy M Kohrt
- Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Veterans Affairs Eastern Colorado Geriatric Research, Educational and Clinical Center, Denver, CO, United States
| | - Kerrie L Moreau
- Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Veterans Affairs Eastern Colorado Geriatric Research, Educational and Clinical Center, Denver, CO, United States
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2
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Evaluation of Heart Rate Variability and Application of Heart Rate Variability Biofeedback: Toward Further Research on Slow-Paced Abdominal Breathing in Zen Meditation. Appl Psychophysiol Biofeedback 2022; 47:345-356. [PMID: 35579767 DOI: 10.1007/s10484-022-09546-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/27/2022] [Indexed: 11/02/2022]
Abstract
This review summarizes my own involvement in heart rate variability (HRV) and HRV biofeedback studies, as a tribute to the late Dr. Evgeny Vaschillo. I first review psychophysiological studies on behavioral stress and relaxation performed in my laboratory using an assessment of cardiac parasympathetic activity. Although magnitude of high-frequency (HF) component of HRV corresponding respiratory sinus arrhythmia (RSA) is widely used as an index of cardiac parasympathetic function, a respiratory confound during stress or relaxation may have interfered with the proper assessment of the HF HRV. An enhanced method under frequency-controlled respiration at 0.25 Hz provided a reliable assessment of cardiac parasympathetic activity. I then review findings from HRV biofeedback research in my laboratory. Based on the hypothesis that RSA measured as an HF component of HRV represents cardiorespiratory resting function, it was demonstrated that HRV biofeedback before sleep enhanced the magnitude of HF HRV during sleep, a cardiorespiratory resting function. Moreover, by focusing on the spectral peak of the low-frequency (LF) component of HRV, paced breathing at the LF-peak frequency was shown to increase baroreflex sensitivity. Finally, I describe the potential of slow-paced abdominal breathing (i.e., Tanden breathing) performed in Zen meditation. The concept of Tanden breathing as described in a regimen from early modern Japan is introduced, and recent research findings on slow-paced abdominal breathing are summarized. Future research directions of slow-paced abdominal breathing are also discussed.
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3
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Kozorosky EM, Lee CH, Lee JG, Nunez Martinez V, Padayachee LE, Stauss HM. Transcutaneous auricular vagus nerve stimulation augments postprandial inhibition of ghrelin. Physiol Rep 2022; 10:e15253. [PMID: 35441808 PMCID: PMC9020171 DOI: 10.14814/phy2.15253] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 05/15/2023] Open
Abstract
Vagus nerve stimulation (VNS) facilitates weight loss in animals and patients treated with VNS for depression or epilepsy. Likewise, chronic transcutaneous auricular VNS (taVNS) reduces weight gain and improves glucose tolerance in Zucker diabetic fatty rats. If these metabolic effects of taVNS observed in rats translate to humans is unknown. Therefore, the hypothesis of this study was that acute application of taVNS affects glucotropic and orexigenic hormones which could potentially facilitate weight loss and improve glucose tolerance if taVNS were applied chronically. In two single-blinded randomized cross-over protocols, blood glucose levels, plasma concentrations of insulin, C-peptide, glucagon, leptin, and ghrelin, together with heart rate variability and baroreceptor-heart rate reflex sensitivity were determined before and after taVNS (left ear, 10 Hz, 300 µs, 2.0-2.5 mA, 30 min) or sham-taVNS (electrode attached to ear with the stimulator turned off). In a first protocol, subjects (n = 16) were fasted throughout the protocol and in a second protocol, subjects (n = 10) received a high-calorie beverage (220 kCal) after the first blood sample, just before initiation of taVNS or sham-taVNS. No significant effects of taVNS on heart rate variability and baroreceptor-heart rate reflex sensitivity and only minor effects on glucotropic hormones were observed. However, in the second protocol taVNS significantly lowered postprandial plasma ghrelin levels (taVNS: -115.5 ± 28.3 pg/ml vs. sham-taVNS: -51.2 ± 30.6 pg/ml, p < 0.05). This finding provides a rationale for follow-up studies testing the hypothesis that chronic application of taVNS may reduce food intake through inhibition of ghrelin and, therefore, may indirectly improve glucose tolerance through weight loss.
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Affiliation(s)
| | - Cristina H. Lee
- Burrell College of Osteopathic MedicineLas CrucesNew MexicoUSA
| | - Jessica G. Lee
- Burrell College of Osteopathic MedicineLas CrucesNew MexicoUSA
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Effects of High-Intensity Interval Training on the Vascular and Autonomic Components of the Baroreflex at Rest in Adolescents. Pediatr Exerc Sci 2022; 34:13-19. [PMID: 34311441 DOI: 10.1123/pes.2020-0220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 06/04/2021] [Accepted: 06/09/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE In a sample of healthy adolescents, the authors aimed to investigate the effects of high-intensity interval exercise (HIIE) training and detraining on baroreflex sensitivity (BRS) and it's vascular and autonomic components at rest. METHODS Nineteen volunteers were randomly allocated to (1) 4 weeks HIIE training performed 3 times per week or (2) a control condition with no intervention for the same duration as HIIE training. PRE, POST, and following 2 weeks of detraining resting supine heart rate and blood pressure were measured, and a cross-spectral method (integrated gain [gain in low frequency]) was used to determine BRS gain. Arterial compliance (AC) was assessed as the BRS vascular component. LFgain divided by AC (LFgain/AC) was used as the autonomic determinant of BRS. RESULTS The HIIE training was completed with 100% compliance. HIIE did not change resting gain in low frequency (LFgain) (P = .66; effect size = 0.21), AC (P = .44; effect size = 0.36), or LFgain/AC (P = .68; effect size = 0.19) compared to control. CONCLUSION Four weeks of HIIE training does not change BRS and its autonomic and vascular determinant in a sample of healthy adolescents at rest.
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5
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Efficacy of Paced Breathing at the Low-frequency Peak on Heart Rate Variability and Baroreflex Sensitivity. Appl Psychophysiol Biofeedback 2020; 45:31-37. [PMID: 31781925 DOI: 10.1007/s10484-019-09453-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We developed a simple method for identifying resonance frequency by focusing on the spectral peak of the low-frequency (LF) component of heart rate variability (HRV) and examined the hypothesis that paced breathing at an accurate resonance frequency increases HRV and baroreflex sensitivity (BRS). We assessed a peak frequency of the LF component of the resting HRV by using power spectral analysis under respiratory control at 0.25 Hz, and a resonance frequency, which was evaluated by using the standard breathing maneuver (Lehrer 2007). We examined the effects of paced breathing at the peak frequency of the LF component (Spectral condition) and paced breathing at the resonance frequency as determined by the standard breathing maneuver (Standard condition) on HRV and BRS in 28 healthy college students and young adults. Electrocardiogram, respiration, and noninvasive continuous blood pressure was recorded during a 5-min baseline, followed by a 5-min paced breathing session. Results indicated that the BRS increased during the breathing session under both conditions, but the increase in BRS under the Spectral condition was higher than the Standard condition (p < .05). The LF amplitude increased during the breathing session under both conditions (p < .001), although the difference between the conditions was not significant. These results suggest that paced breathing at the peak frequency of the LF component enhanced the autonomic baroreflex function. Moreover, assessment of the LF-peak may provide more accurate information on resonance frequency for paced breathing during HRV biofeedback.
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6
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The prevalence of masked hypertension in relation to cigarette smoking in a Chinese male population. J Hypertens 2020; 38:1056-1063. [DOI: 10.1097/hjh.0000000000002392] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Cseh D, Climie RE, Offredo L, Guibout C, Thomas F, Zanoli L, Danchin N, Sharman JE, Laurent S, Jouven X, Boutouyrie P, Empana JP. Type 2 Diabetes Mellitus Is Independently Associated With Decreased Neural Baroreflex Sensitivity: The Paris Prospective Study III. Arterioscler Thromb Vasc Biol 2020; 40:1420-1428. [PMID: 32188272 DOI: 10.1161/atvbaha.120.314102] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Impaired baroreflex function is an early indicator of cardiovascular autonomic imbalance. Patients with type 2 diabetes mellitus (T2D) have decreased baroreflex sensitivity (BRS), however, whether the neural BRS (nBRS) and mechanical component of the BRS is altered in those with high metabolic risk (HMR, impaired fasting glucose and metabolic syndrome) or with overt T2D, is unknown. We examined this in a community-based observational study, the Paris Prospective Study III (PPS3). Approach and Results: In 7626 adults aged 50 to 75 years, resting nBRS (estimated by low-frequency gain, from carotid distension rate and RR [time elapsed between two successive R waves] intervals) and mechanical BRS were measured by high-precision carotid echotracking. The associations between overt T2D or HMR as compared with subjects with normal glucose metabolism and nBRS or mechanical BRS were quantified using multivariable linear regression analysis. There were 319 subjects with T2D (61±6 years, 77% male), 1450 subjects with HMR (60±6 years, 72% male), and 5857 subjects with normal glucose metabolism (59±6 years, 57% male). Compared with normal glucose metabolism, nBRS was significantly lower in HMR subjects (β=-0.07 [95% CI, -0.12 to -0.01]; P=0.029) and in subjects with T2D (β=-0.18 [95% CI, -0.29 to -0.07]; P=0.002) after adjustment for confounding and mediating factors. Subgroup analysis suggests significant and independent alteration in mechanical BRS only among HMR patients who had both impaired fasting glucose and metabolic syndrome. CONCLUSIONS In this community-based study of individuals aged 50 to 75, a graded decrease in nBRS was observed in HMR subjects and patients with overt T2D as compared with normal glucose metabolism subjects.
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Affiliation(s)
- Domonkos Cseh
- From the Department of Physiology, Semmelweis University, Budapest, Hungary (D.C.)
| | - Rachel E Climie
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.).,Baker Heart and Diabetes Institute, Melbourne, Australia (R.E.C.).,Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (R.E.C., J.E.S.)
| | - Lucile Offredo
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.)
| | - Catherine Guibout
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.)
| | - Frédérique Thomas
- Investigations Préventives et Cliniques (IPC), Paris, France (F.T., N.D.)
| | - Luca Zanoli
- University of Catania, Catania, Italy (L.Z.)
| | - Nicolas Danchin
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.).,Investigations Préventives et Cliniques (IPC), Paris, France (F.T., N.D.).,Department of Pharmacology, HEGP, APHP, Paris, France (N.D., S.L., P.B.)
| | - James E Sharman
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia (R.E.C., J.E.S.)
| | - Stéphane Laurent
- Department of Pharmacology, HEGP, APHP, Paris, France (N.D., S.L., P.B.)
| | - Xavier Jouven
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.)
| | - Pierre Boutouyrie
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.).,Department of Pharmacology, HEGP, APHP, Paris, France (N.D., S.L., P.B.)
| | - Jean-Philippe Empana
- Université de Paris, INSERM U970, Paris Cardiovascular Research Centre (PARCC), Integrative Epidemiology of Cardiovascular Disease team, Paris, France (R.E.C., L.O., C.G., N.D., X.J., P.B., J.-P.E.)
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Sheng CS, Li FK, Cheng YB, Wei FF, Huang JF, Guo QH, Zhang DY, Wang Y, An DW, Huang QF, Li Y, Wang JG. Blood pressure and heart rate variability and baroreflex sensitivity in white-coat, masked, and sustained hypertension. Hypertens Res 2020; 43:772-780. [PMID: 32051566 DOI: 10.1038/s41440-020-0413-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 01/16/2020] [Accepted: 01/23/2020] [Indexed: 02/06/2023]
Abstract
We investigated blood pressure (BP) and heart rate variability and baroreflex sensitivity (BRS) in white-coat, masked and sustained hypertension in untreated patients (n = 645). Normotension and white-coat, masked, and sustained hypertension were defined according to the clinic (cutoff 140/90 mmHg) and 24-h ambulatory (130/80 mmHg) BPs. The Finometer device recorded beat-to-beat finger BP and electrocardiograms in the supine and standing positions for the computation of frequency-domain power-spectral BP and heart rate variability indexes and BRS. In multivariate analysis, BP variability indexes in the supine position differed significantly (P < 0.0001) for both low-frequency (LF) and high-frequency (HF) components and the LF/HF ratio, with the lowest LF and HF power and highest LF/HF ratio in white-coat hypertension (n = 28), the highest LF and HF power and lowest LF/HF ratio in sustained hypertension (n = 198), and intermediate values in normotension (n = 189) and masked hypertension (n = 230). These differences diminished in the standing position, being significant (P < 0.0001) only for the LF component variability. The LF/HF ratio in BP in the supine position decreased with advancing age in normotension and sustained hypertension (P ≤ 0.03) but not white-coat or masked hypertension (P ≥ 0.12). For heart rate variability, a significant difference was observed only for the LF component in the supine position (P = 0.0005), which was lowest in white-coat hypertension. BRS in masked and sustained hypertension was significantly (P ≤ 0.0001) lower than that in normotension in both supine and standing positions and decreased with advancing age (P ≤ 0.0001). In conclusion, masked, but not white-coat, hypertension showed similar patterns of, but slightly less severe, changes in BP and heart rate variability and BRS to sustained hypertension.
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Affiliation(s)
- Chang-Sheng Sheng
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Fei-Ka Li
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yi-Bang Cheng
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Fang-Fei Wei
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jian-Feng Huang
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Qian-Hui Guo
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Dong-Yan Zhang
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ying Wang
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - De-Wei An
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Qi-Fang Huang
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yan Li
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ji-Guang Wang
- Centre for Epidemiological Studies and Clinical Trials and Centre for Vascular Evaluations, Shanghai Key Lab of Hypertension, Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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Amelard R, Murray KR, Hedge ET, Cleworth TW, Noguchi M, Laing AC, Hughson RL. Monocular 3D Sway Tracking for Assessing Postural Instability in Cerebral Hypoperfusion During Quiet Standing. IEEE Trans Neural Syst Rehabil Eng 2020; 28:720-729. [PMID: 32012020 DOI: 10.1109/tnsre.2020.2971340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Postural instability is prevalent in aging and neurodegenerative disease, decreasing quality of life and independence. Quantitatively monitoring balance control is important for assessing treatment efficacy and rehabilitation progress. However, existing technologies for assessing postural sway are complex and expensive, limiting their widespread utility. Here, we propose a monocular imaging system capable of assessing sub-millimeter 3D sway dynamics during quiet standing. Two anatomical targets with known feature geometries were placed on the lumbar and shoulder. Upper and lower trunk 3D kinematic motion were automatically assessed from a set of 2D frames through geometric feature tracking and an inverse motion model. Sway was tracked in 3D and compared between control and hypoperfusion conditions in 14 healthy young adults. The proposed system demonstrated high agreement with a commercial motion capture system (error [Formula: see text], [-0.52, 0.52]). Between-condition differences in sway dynamics were observed in anterior-posterior sway during early and mid stance, and medial-lateral sway during mid stance commensurate with decreased cerebral perfusion, followed by recovered sway dynamics during late stance with cerebral perfusion recovery. This inexpensive single-camera system enables quantitative 3D sway monitoring for assessing neuromuscular balance control in weakly constrained environments.
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Katzelnick CG, Weir JP, Chiaravalloti ND, Wylie GR, Dyson-Hudson TA, Bauman WA, Wecht JM. Impact of Blood Pressure, Lesion Level, and Physical Activity on Aortic Augmentation Index in Persons with Spinal Cord Injury. J Neurotrauma 2017; 34:3407-3415. [DOI: 10.1089/neu.2017.5065] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Caitlyn G. Katzelnick
- VA RR&D National Center for Medication Consequences of Spinal Cord Injury, James J Peters VA Medical Center, Bronx, New York
- Department of Research, Kessler Foundation, West Orange, New Jersey
| | - Joseph P. Weir
- Department of Health, Sport, and Exercise Science, University of Kansas, Lawrence, Kansas
| | - Nancy D. Chiaravalloti
- Department of Research, Kessler Foundation, West Orange, New Jersey
- Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, New Jersey
| | - Glenn R. Wylie
- Department of Research, Kessler Foundation, West Orange, New Jersey
- The War Related Illness and Injury Study Center, VA New Jersey Health Care System, East Orange, New Jersey
| | - Trevor A. Dyson-Hudson
- Department of Research, Kessler Foundation, West Orange, New Jersey
- Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, New Jersey
| | - William A. Bauman
- VA RR&D National Center for Medication Consequences of Spinal Cord Injury, James J Peters VA Medical Center, Bronx, New York
- Department of Medicine, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jill M. Wecht
- VA RR&D National Center for Medication Consequences of Spinal Cord Injury, James J Peters VA Medical Center, Bronx, New York
- Department of Medicine, The Icahn School of Medicine at Mount Sinai, New York, New York
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van Bilsen M, Patel HC, Bauersachs J, Böhm M, Borggrefe M, Brutsaert D, Coats AJS, de Boer RA, de Keulenaer GW, Filippatos GS, Floras J, Grassi G, Jankowska EA, Kornet L, Lunde IG, Maack C, Mahfoud F, Pollesello P, Ponikowski P, Ruschitzka F, Sabbah HN, Schultz HD, Seferovic P, Slart RHJA, Taggart P, Tocchetti CG, Van Laake LW, Zannad F, Heymans S, Lyon AR. The autonomic nervous system as a therapeutic target in heart failure: a scientific position statement from the Translational Research Committee of the Heart Failure Association of the European Society of Cardiology. Eur J Heart Fail 2017; 19:1361-1378. [PMID: 28949064 DOI: 10.1002/ejhf.921] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 04/23/2017] [Accepted: 05/24/2017] [Indexed: 12/20/2022] Open
Abstract
Despite improvements in medical therapy and device-based treatment, heart failure (HF) continues to impose enormous burdens on patients and health care systems worldwide. Alterations in autonomic nervous system (ANS) activity contribute to cardiac disease progression, and the recent development of invasive techniques and electrical stimulation devices has opened new avenues for specific targeting of the sympathetic and parasympathetic branches of the ANS. The Heart Failure Association of the European Society of Cardiology recently organized an expert workshop which brought together clinicians, trialists and basic scientists to discuss the ANS as a therapeutic target in HF. The questions addressed were: (i) What are the abnormalities of ANS in HF patients? (ii) What methods are available to measure autonomic dysfunction? (iii) What therapeutic interventions are available to target the ANS in patients with HF, and what are their specific strengths and weaknesses? (iv) What have we learned from previous ANS trials? (v) How should we proceed in the future?
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Affiliation(s)
- Marc van Bilsen
- Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Hospital, Maastricht, the Netherlands
| | - Hitesh C Patel
- National Institute for Health Research (NIHR) Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK.,Baker Heart and Diabetes Institute, Melbourne, Vic, Australia
| | - Johann Bauersachs
- Department of Cardiology and Angiology, Medical School Hannover, Hannover, Germany
| | - Michael Böhm
- Clinic for Internal Medicine III, Cardiology, Angiology and Intensive Internal Medicine, Homburg, Germany
| | - Martin Borggrefe
- First Department of Medicine, Cardiology Division, University Medical Centre Mannheim, Mannheim, Germany.,German Centre for Cardiovascular Research, Mannheim, Germany
| | - Dirk Brutsaert
- Department of Cardiology, Antwerp University, Antwerp, Belgium
| | - Andrew J S Coats
- Department of Medicine, Monash University, Melbourne, Vic, Australia.,Department of Medicine, University of Warwick, Coventry, UK
| | - Rudolf A de Boer
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, the Netherlands
| | | | - Gerasimos S Filippatos
- Department of Cardiology, School of Medicine, National and Kapodistrian University of Athens, Athens University Hospital Attikon, Athens, Greece
| | - John Floras
- University Health Network and Sinai Health System Division of Cardiology, Peter Munk Cardiac Centre, Toronto General and Lunenfeld-Tanenbaum Research Institutes, University of Toronto, Toronto, ON, Canada
| | - Guido Grassi
- Clinica Medica, Department of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy.,IRCCS Multimedica, Milan, Italy
| | - Ewa A Jankowska
- Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland.,Centre for Heart Diseases, Military Hospital, Wroclaw, Poland
| | - Lilian Kornet
- Medtronic, Inc., Bakken Research Centre, Maastricht, the Netherlands
| | - Ida G Lunde
- Institute for Experimental Medical Research, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Christoph Maack
- Clinic for Internal Medicine III, Cardiology, Angiology and Intensive Internal Medicine, Homburg, Germany
| | - Felix Mahfoud
- Clinic for Internal Medicine III, Cardiology, Angiology and Intensive Internal Medicine, Homburg, Germany
| | | | - Piotr Ponikowski
- Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland.,Centre for Heart Diseases, Military Hospital, Wroclaw, Poland
| | - Frank Ruschitzka
- University Heart Centre, University Hospital Zurich, Zurich, Switzerland
| | - Hani N Sabbah
- Department of Medicine, Division of Cardiovascular Medicine, Henry Ford Hospital, Detroit, MI, USA
| | - Harold D Schultz
- Department of Cellular and Integrative Physiology, University of Nebraska College of Medicine, Omaha, NE, USA
| | - Petar Seferovic
- Department of Cardiology, Belgrade University Medical Centre, Belgrade, Serbia
| | - Riemer H J A Slart
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Centre Groningen, Groningen, the Netherlands.,Department of Biomedical Photonic Imaging, Faculty of Science and Technology, University of Twente, Enschede, the Netherlands
| | - Peter Taggart
- Department of Cardiovascular Science, University College London, Barts Heart Centre, London, UK
| | - Carlo G Tocchetti
- Department of Translational Medical Sciences, Federico II University, Naples, Italy
| | - Linda W Van Laake
- Department of Cardiology, Heart and Lungs Division, and Regenerative Medicine Centre, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Faiez Zannad
- INSERM, Centre for Clinical Investigation 9501, Unit 961, University Hospital Centre, Nancy, France.,Department of Cardiology, Nancy University, University of the Lorraine, Nancy, France
| | - Stephane Heymans
- Netherlands Heart Institute, Utrecht, the Netherlands.,Department of Cardiovascular Sciences, Leuven University, Leuven, Belgium
| | - Alexander R Lyon
- National Institute for Health Research (NIHR) Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
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12
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Empana JP, Prugger C, Thomas F, Perier MC, Zanoli L, Castiglioni P, Guibout C, Causeret S, Barnes C, Lemogne C, Parati G, Laurent S, Pannier B, Boutouyrie P, Jouven X. Serotonin and norepinephrine reuptake inhibitors antidepressant use is related to lower baroreflex sensitivity independently of the severity of depressive symptoms. A community-study of 9213 participants from the Paris Prospective Study III. Atherosclerosis 2016; 251:55-62. [PMID: 27266822 DOI: 10.1016/j.atherosclerosis.2016.05.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/02/2016] [Accepted: 05/25/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND AIMS We assess the respective relationship of high depressive symptoms and antidepressant use (ATD) with baroreflex sensitivity (BRS) in subjects from the community who enrolled the Paris Prospective Study III. METHODS Recruitment took place in a large health preventive centre in Paris (France), between May 2008 and June 2012. BRS was investigated by spectral analysis of the spontaneous carotid distension rate and RR intervals using non-invasive high-resolution ultrasound carotid-echotracking. A total score ≥7 on a 13-item standardized questionnaire defined the presence of high depressive symptoms. Information on ATD use was obtained on a face-to-face interview with a medical doctor who checked the most recent medical prescriptions and/or medical package. RESULTS There were 9213 participants aged 50-75 years (38.6% of women), including 5.6% with high-depressive symptoms and 5.2% on ATD. High depressive symptoms were not associated with low BRS (below the median) even in unadjusted logistic regression analysis (OR = 1.09; 95%CI: 0.91-1.30). Instead, ATD use was related to low BRS in multivariate logistic regression analysis (OR = 1.27; 95% CI: 1.04-1.54). This association remains after adjusting for and matching on propensity score of receiving ATD. A specific association with serotonin and norepinephrine reuptake inhibitors was observed (OR = 1.94; 95% CI: 1.16-3.22). CONCLUSIONS ATD use and serotonin and norepinephrine reuptake inhibitors in particular, but not high depressive symptoms, is associated with low BRS. If confirmed, these results may bring novel insights into the mechanisms linking depressive symptoms and/or ATD use with cardiovascular disease onset.
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Affiliation(s)
- Jean-Philippe Empana
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France.
| | - Christof Prugger
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | | | - Marie-Cécile Perier
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | | | | | - Catherine Guibout
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | - Sophie Causeret
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | - Caroline Barnes
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France
| | - Cédric Lemogne
- Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France; INSERM, U894, Centre Psychiatrie et Neuroscience, Paris, France; APHP, Georges Pompidou European Hospital, Departments of Psychiatry, Paris, France
| | - Gianfranco Parati
- Department of Cardiology, Istituto Auxologico Italiano, Milan, Italy; Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Stéphane Laurent
- Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France; INSERM, UMR-S970, Department of Pharmacology of Arterial Wall Mechanics, Paris, France; APHP, Georges Pompidou European Hospital, Department of Pharmacology, Paris, France
| | - Bruno Pannier
- Preventive and Clinical Investigation Centre, Paris, France
| | - Pierre Boutouyrie
- Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France; INSERM, UMR-S970, Department of Pharmacology of Arterial Wall Mechanics, Paris, France; APHP, Georges Pompidou European Hospital, Department of Pharmacology, Paris, France
| | - Xavier Jouven
- INSERM, UMR-S970, Department of Epidemiology, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine, Paris, France; APHP, Georges Pompidou European Hospital, Department of Cardiology, Paris, France
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13
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Phillips AA, Krassioukov AV, Ainslie PN, Cote AT, Warburton DER. Increased central arterial stiffness explains baroreflex dysfunction in spinal cord injury. J Neurotrauma 2014; 31:1122-8. [PMID: 24634993 DOI: 10.1089/neu.2013.3280] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
After cervical spinal cord injury (SCI), orthostatic hypotension and intolerance commonly ensue. The cardiovagal baroreflex plays an important role in the acute regulation of blood pressure (BP) and is associated with the onset of presyncope. The cardiovagal baroreflex is dysfunctional after SCI; however, this may be influenced by either increased stiffening of the arteries containing the stretch-receptors (which has been shown in SCI) or a more downstream neural mechanism (i.e., solitary nucleus, sinoatrial node). Identifying where along this pathway baroreflex dysfunction occurs may highlight a potential therapeutic target. This study examined the relationship between spontaneous cardiovagal baroreflex sensitivity (BRS) and common carotid artery (CCA) stiffness in those with high level SCI before and after midodrine (alpha1-agonist) administration, as well as in able-bodied controls, to evaluate: (1) the role arterial stiffening plays mediating baroreflex function after SCI and (2) the effect of normalizing BP on these parameters. Three to five min recordings of beat-by-beat BP and heart rate, as well as 30 sec duration recordings of CCA diameter were used for analysis. All participants were tested supine and during upright-tilt. Arterial stiffness (β-stiffness index) was elevated in those with SCI when upright (+12%; p<0.05). Further, β-stiffness index was negatively related to reduced BRS in those with SCI when upright (R2=0.55; p<0.05), but not in able-bodied persons. Normalizing BP did not improve BRS or CCA stiffness. This study clearly shows that reduced BRS is closely related to increased arterial stiffness in the population with SCI.
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Affiliation(s)
- Aaron A Phillips
- 1 Cardiovascular Physiology and Rehabilitation Laboratory , Physical Activity Promotion and Chronic Disease Prevention Unit, University of British Columbia , Vancouver, Canada
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14
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Boutouyrie P, Zanoli L, Briet M, Karras A, Delahousse M. Baroreflex sensitivity after kidney transplantation: arterial or neural improvement? Nephrol Dial Transplant 2014; 28:2401-3. [PMID: 24078637 DOI: 10.1093/ndt/gft341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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15
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Edwards KM, Wilson KL, Sadja J, Ziegler MG, Mills PJ. Effects on blood pressure and autonomic nervous system function of a 12-week exercise or exercise plus DASH-diet intervention in individuals with elevated blood pressure. Acta Physiol (Oxf) 2011; 203:343-50. [PMID: 21649862 DOI: 10.1111/j.1748-1716.2011.02329.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIM Hypertension is related to abnormalities in autonomic nervous system (ANS) function, with increased sympathetic output and decreased parasympathetic tone. Lifestyle interventions are the first line of treatment in hypertension, and decreased blood pressure (BP) effects may be related to changes in ANS function. Using heart rate recovery (HRR) from exercise as an index of parasympathetic tone and plasma noradrenaline as an index of sympathetic tone, we investigated the effects of lifestyle interventions on ANS function in patients with elevated BP. METHODS Sedentary participants with elevated BP were randomly assigned to either an exercise only (N = 25), exercise plus dietary approaches to stop hypertension (DASH) diet (N = 12), or waitlist control (N = 15) 12-week intervention. Plasma noradrenaline was measured at rest and participants performed a peak exercise test before and after the intervention. HRR was calculated as peak heart rate (HR) minus HR at 1 min post-exercise. RESULTS Heart rate recovery showed a significant group by time interaction; both intervention groups showed increases in HRR from pre- to post-intervention, while waitlist showed no change. Similarly, both exercise plus diet and exercise groups, but not waitlist, showed significant reductions in BP from pre- to post-intervention. Linear regression revealed that BP post-intervention was significantly predicted by change in HRR when controlling for pre-BP, age, gender and BMI. CONCLUSIONS Lifestyle interventions induced training-reduced BP and altered autonomic tone, indexed by HRR. This study indicates the importance of behavioural modification in hypertension and that increased parasympathetic function is associated with success in reduction of BP.
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Affiliation(s)
- K M Edwards
- University of Sydney, Exercise Health and Performance Research Group, Lidcombe, Australia.
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16
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Empana JP, Bean K, Guibout C, Thomas F, Bingham A, Pannier B, Boutouyrie P, Jouven X. Paris Prospective Study III: a study of novel heart rate parameters, baroreflex sensitivity and risk of sudden death. Eur J Epidemiol 2011; 26:887-92. [PMID: 21964902 DOI: 10.1007/s10654-011-9618-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 09/17/2011] [Indexed: 02/03/2023]
Abstract
Resting heart rate has been related to the risk of cardiovascular disease and sudden death in several large prospective studies. To investigate prospectively the association of novel heart rate parameters and of carotid artery stiffness with sudden death and other cardiovascular disease. The Paris Prospective Study III (PPS3) is a new, ongoing French prospective study. From June 2008 to December 2011, 10,000 men and women aged 50-75 years who will have a preventive medical check-up at the Centre d'Investigations Préventives et Cliniques in Paris (France), will be enrolled in the study, after signing an informed consent. In addition to the general health examination, each subject's heart rhythm will be recorded during the course of the health check-up (approximately 2(1/2) h) and an echo-tracking of the right carotid bulb will be performed by trained technicians. A bio bank and DNA bank will be established for further biomarker and genetic analyses. The occurrence of cardiovascular disease including acute coronary syndrome, stroke, peripheral artery disease and sudden death, and of mortality, of the participants will be followed up during 20 years. With an estimated mean annual rate of sudden death of 0.1% and its increasing incidence rate with age, between 250 and 300 sudden deaths are expected. This unique study should provide new insights into the regulation of heart rate and blood pressure and should enable to identify novel heart rate parameters that are associated with sudden death.
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Affiliation(s)
- Jean-Philippe Empana
- Paris Cardiovascular Research Centre, University Paris Descartes, and Assistance Publique des Hôpitaux de Paris, UMR-S970, Paris, France.
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17
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van Lill L, Malan L, van Rooyen J, Steyn F, Reimann M, Ziemssen T. Baroreceptor sensitivity, cardiovascular responses and ECG left ventricular hypertrophy in men: the SABPA study. Blood Press 2011; 20:355-61. [PMID: 21545353 DOI: 10.3109/08037051.2011.580529] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIM. Research has shown a significant relationship between hypertension and attenuated baroreceptor sensitivity (BRS), which in turn reflects alterations of autonomic control of the cardiovascular system. The objective of this study was to compare the BRS of African and Caucasian men and determine possible associations with blood pressure and left ventricular hypertrophy. MATERIALS AND METHODS. Participants included African (n = 82) and Caucasian (n = 100) male teachers, aged between 20 and 65 years, recruited in the North-West Province, South Africa. Ambulatory blood pressure monitoring was conducted for a 22-23-h period and, thereafter, cardiovascular parameters were recorded with a Finometer and 12-lead ECG during rest and while challenging the cardiovascular system with the cold pressor and Stroop color?word conflict tests. Spontaneous BRS was calculated as well as the Cornell product [marker of left ventricular hypertrophy (LVH)]. RESULTS. The African men had significantly lower BRS stress responses. Attenuated BRS coupled to an ?-adrenergic response pattern predicted elevation of blood pressure in the African men. BRS reduction did not prove to be a significant predictor of LVH. CONCLUSION. Lower BRS, especially during stress, may pose a significant health threat for African men regarding earlier development or promotion of α -adrenergic-driven hypertension and greater risk for cardiovascular disease.
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Affiliation(s)
- Lisa van Lill
- Hypertension in Africa Research Team (HART), School for Physiology, Nutrition and Consumer Science Sciences
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18
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Hypertensive effects of central angiotensin II infusion and restraint stress are reduced with age. J Hypertens 2010; 28:1298-306. [PMID: 20308921 DOI: 10.1097/hjh.0b013e328338a075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE We investigated the effect of age on cardiovascular responses mediated by central angiotensin II (AngII) after intracerebroventricular infusion of AngII, and during restraint stress. METHODS Blood pressure (BP) and heart rate (HR) of young (5-month-old) and old (27-month-old) male Fischer-344 x Brown-Norway rats were measured using radiotelemetry. AngII was infused intracerebroventricularly using osmotic minipumps (10 ng/0.5 microl/h for 11 days). BP and HR responses to stress were evaluated by placing animals in restrainers for 20 min before and after intracerebroventricular infusion of the AngII-type-1 receptor inhibitor losartan (15 microg/microl per h for 3 days). RESULTS Resting BP was significantly elevated and HR was significantly lower in old rats compared with young. AngII-induced BP increase was markedly reduced in old rats, but HR responses were similar. Diurnal variation of both BP and HR was lower in old animals, and AngII reduced the amplitude of BP variation in young rats, but not in old. Restraint stress-induced BP and HR elevations were reduced with age. BP responses were diminished by central losartan infusion in both young and old, but this effect was more significant in young rats. In addition, expression of CuZn-superoxide dismutase and catalase declined significantly with age in the hypothalamus, whereas baseline oxidative stress increased. In contrast, AngII-induced increase in hypothalamic oxidative stress decreased with age. CONCLUSION This study demonstrates that the role of central AngII diminishes with age in the regulation of BP both during baseline conditions and during stress, whereas the involvement of AngII in the regulation of HR remains unaffected.
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19
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Trigonometric regressive spectral analysis reliably maps dynamic changes in baroreflex sensitivity and autonomic tone: the effect of gender and age. PLoS One 2010; 5:e12187. [PMID: 20808439 PMCID: PMC2922332 DOI: 10.1371/journal.pone.0012187] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Accepted: 07/22/2010] [Indexed: 11/19/2022] Open
Abstract
Background The assessment of baroreflex sensitivity (BRS) has emerged as prognostic tool in cardiology. Although available computer-assisted methods, measuring spontaneous fluctuations of heart rate and blood pressure in the time and frequency domain are easily applicable, they do not allow for quantification of BRS during cardiovascular adaption processes. This, however, seems an essential criterion for clinical application. We evaluated a novel algorithm based on trigonometric regression regarding its ability to map dynamic changes in BRS and autonomic tone during cardiovascular provocation in relation to gender and age. Methodology/Principal Findings We continuously recorded systemic arterial pressure, electrocardiogram and respiration in 23 young subjects (25±2 years) and 22 middle-aged subjects (56±4 years) during cardiovascular autonomic testing (metronomic breathing, Valsalva manoeuvre, head-up tilt). Baroreflex- and spectral analysis was performed using the algorithm of trigonometric regressive spectral analysis. There was an age-related decline in spontaneous BRS and high frequency oscillations of RR intervals. Changes in autonomic tone evoked by cardiovascular provocation were observed as shifts in the ratio of low to high frequency oscillations of RR intervals and blood pressure. Respiration at 0.1 Hz elicited an increase in BRS while head-up tilt and Valsalva manoeuvre resulted in a downregulation of BRS. The extent of autonomic adaption was in general more pronounced in young individuals and declined stronger with age in women than in men. Conclusions/Significance The trigonometric regressive spectral analysis reliably maps age- and gender-related differences in baroreflex- and autonomic function and is able to describe adaption processes of baroreceptor circuit during cardiovascular stimulation. Hence, this novel algorithm may be a useful screening tool to detect abnormalities in cardiovascular adaption processes even when resting values appear to be normal.
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20
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An independent relationship between muscle sympathetic nerve activity and pulse wave velocity in normal humans. J Hypertens 2010; 28:979-84. [PMID: 20408258 DOI: 10.1097/hjh.0b013e328336ed9a] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Carotid-femoral pulse wave velocity (PWV) has been shown to be a powerful predictor of cardiovascular morbidity and mortality. Sympathetic neural mechanisms may have a stiffening influence on arterial mechanical properties. The relationship between direct measures of sympathetic traffic and PWV in healthy humans has not been previously studied. We, therefore, tested the hypothesis that PWV is independently linked to muscle sympathetic nerve activity (MSNA) in normal individuals. METHODS We measured MSNA (microneurography), PWV (Complior device), heart rate and blood pressure in 25 healthy male participants (mean age 43 +/- 10 years). RESULTS PWV correlated significantly with age (r = 0.63, P < 0.001), SBP (r = 0.43, P < 0.05) and MSNA (r = 0.43, P < 0.05) but not with BMI, waist circumference, waist-to-hip ratio, heart rate, pulse pressure or DBP. Robust multiple linear regression analysis revealed that only age and MSNA were linked independently to PWV (r2 = 0.62, P < 0.001), explaining 39 and 25% of its variance, respectively. After adjustment of PWV for age and SBP, we further divided individuals into 'excessive' PWV (i.e. higher than expected from age and SBP) and 'optimal' PWV (i.e. lower than expected). BMI and blood pressure were similar in both subgroups. Individuals with excessive PWV had significantly greater MSNA than individuals with optimal PWV (30 +/- 10 vs. 18 +/- 11 bursts/min, P = 0.01). CONCLUSION This study provides the first evidence that PWV is linked to MSNA in normal humans. The relationship between MSNA and PWV is independent of age, BMI, waist circumference, waist-to-hip ratio, heart rate, pulse pressure or blood pressure.
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McIntyre CW, John SG, Jefferies HJ. Advances in the cardiovascular assessment of patients with chronic kidney disease. NDT Plus 2008; 1:383-391. [PMID: 28657024 PMCID: PMC5477876 DOI: 10.1093/ndtplus/sfn146] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 08/11/2008] [Indexed: 12/11/2022] Open
Abstract
Cardiovascular mortality is grossly elevated in patients with chronic kidney disease (CKD), and is associated with a wide variety of structural and functional abnormalities. These issues have driven additional attempts to further characterise these abnormalities to elucidate the pathophysiology involved, assess individual risk and/or target and monitor therapies specifically directed at the cardiovascular (CV) system. This review aims to assess the techniques that are currently available for the study of the CV system. This includes conventional assessments of the whole CV system from heart to peripheral microcirculation (although not deal with VC assessment), as well as the key functional consequences relating to stress induced cardiovascular reserve, perfusion and vasoregulation. In addition this review will introduce a variety of techniques aiming to expand the envelope of conventional measurements.
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Affiliation(s)
| | - Stephen G. John
- Department of Renal Medicine, Derby Hospitals NHS Foundation Trust, Derby, UK
| | - Helen J. Jefferies
- Department of Renal Medicine, Derby Hospitals NHS Foundation Trust, Derby, UK
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Yahagi T, Koyama S, Osaka K, Koyama H. Baroreceptors mask sympathetic responses to high intraocular pressure in dogs. Auton Neurosci 2008; 139:55-9. [PMID: 18295549 DOI: 10.1016/j.autneu.2008.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 01/16/2008] [Accepted: 01/21/2008] [Indexed: 11/28/2022]
Abstract
These experiments were designed to investigate whether increasing intraocular pressure (IOP) in anesthetized dogs produces differential control of sympathetic nerve activities to various organs (heart, kidney, liver, and spleen) and if these sympathetic responses are modified by baroreceptors. We performed simultaneous multi-recordings of cardiac, renal, hepatic and splenic sympathetic nerve activities (CNA, RNA, HNA and SpNA, respectively) during 2 min of increasing IOP to a mean pressure of 30 mmHg. After increasing IOP in dogs with the intact baroreceptors, all of measured nerve activities did not change significantly throughout the experiment. In dogs with denervation of baroreceptors (cervical vagotomy with denervation of the carotid sinus and aortic nerves), only RNA and CNA showed significant increases in response to the increased IOP. However, time course changes in HNA and SpNA did not show any significant differences as compared with the baseline or that of the control group. These results indicate that systemic sympathetic nerve responses to increasing IOP are masked by systemic baroreceptors. As animals were denervated of their systemic baroreceptors, the unidirectional sympathoexcitatory responses to increased IOP were observed on CNA and RNA, but not on HNA and SpNA. These sympathetic outflow, when systemic baroreceptors are impaired as observed in old age, may play an important role in management of glaucoma attack with the use of adrenolytic drugs.
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Affiliation(s)
- Toru Yahagi
- Shinshu University School of Medicine, Department of Integrative Physiology and System Control, 3-1-1 Asahi, Matsumoto, Nagano 390, Japan
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23
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Ptaszynski P, Klingenheben T, Gerritse B, Kornet L. Risk stratification after myocardial infarction: a new method of determining the neural component of the baroreflex is potentially more discriminative in distinguishing patients at high and low risk for arrhythmias. ACTA ACUST UNITED AC 2008; 10:227-34. [DOI: 10.1093/europace/eum302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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24
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Mattace-Raso FUS, van den Meiracker AH, Bos WJ, van der Cammen TJM, Westerhof BE, Elias-Smale S, Reneman RS, Hoeks APG, Hofman A, Witteman JCM. Arterial stiffness, cardiovagal baroreflex sensitivity and postural blood pressure changes in older adults: the Rotterdam Study. J Hypertens 2007; 25:1421-6. [PMID: 17563564 DOI: 10.1097/hjh.0b013e32811d6a07] [Citation(s) in RCA: 155] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Arterial stiffness may be involved in the impairment of the arterial baroreflex. In the present study the associations between arterial stiffness and cardiovagal baroreflex sensitivity (BRS) and between BRS and postural blood pressure (BP) changes were investigated within the framework of the Rotterdam Study. METHODS Arterial stiffness was determined by aortic pulse wave velocity and the carotid distensibility coefficient. Continuous recording of the R-R interval and finger BP was performed with the subject resting supine, and BRS was estimated from the spontaneous changes in systolic BP and corresponding interbeat intervals. Measures of aortic stiffness or carotid distensibility and BRS were available in 2490 and 2083 subjects, respectively. The association between arterial stiffness and ln BRS was investigated by multivariate linear regression analysis and then by analysis of covariance, comparing BRS by quartiles of arterial stiffness. RESULTS The mean age of the subjects was 71.7 +/- 6.6 (41.7% men). Aortic stiffness was negatively associated [beta = -0.029; 95% confidence interval (CI): -0.040, -0.019] and the carotid distensibility coefficient positively associated with BRS (beta = 0.017; 95% CI: 0.010, 0.024). An orthostatic decrease in systolic BP was absent in 1609 subjects, between 1 and 10 mmHg in 502 and >10 mmHg in 269 subjects, with corresponding mean values (95% CI) of ln BRS of 1.47 (1.44-1.51), 1.43 (1.37-1.49) and 1.36 (1.28-1.44) ms/mmHg (test for trend P < 0.019). An orthostatic decrease in diastolic BP was absent in 1123 subjects, 1-10 mmHg in 1057 and >10 mmHg in 209 subjects, with corresponding mean values of ln BRS of 1.49 (1.45-1.53), 1.41 (1.37-1.45) and 1.45 (1.36-1.54) ms/mmHg (P < 0.04). CONCLUSION In a large population of older subjects, arterial stiffness appears to be an independent determinant of impaired BRS. Within the same population, impaired BRS was associated with orthostatic BP changes.
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Lewis PM, Smielewski P, Pickard JD, Czosnyka M. Slow oscillations in middle cerebral artery cerebral blood flow velocity and aging. Neurol Res 2007; 29:260-3. [PMID: 17509224 DOI: 10.1179/174313206x153987] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVE A recent study using near infrared spectroscopy (NIRS) showed that low frequency oscillations of regional cerebral blood flow (CBF) decline with age. Using transcranial Doppler ultrasound (TCD), it is possible to monitor similar fluctuations in cerebral blood velocity (CBV) in basal cerebral vessels. Such oscillations have been used widely in the assessment of cerebral autoregulation. We postulated that it should be possible to observe similar age related reductions in the amplitude of slow waves recorded using TCD. METHODS We studied 187 patients with head injury, who were admitted to Addenbrooke's Neuro Critical Care unit between 1992 and 1998. Intermittent recordings of CBV were undertaken using TCD, which were subsequently analysed using software developed in-house. Power spectra were computed in the very low frequency (VLF: 0.01-0.05 Hz) and low frequency (LF: 0.07-0.11 Hz) ranges for all signals and a regression analysis was performed to assess the correlation between power in each frequency band and age. RESULTS No significant correlation was found between VLF or LF power and age (VLF: r=0.037; p=0.63; LF: r=-0.05, p=0.517). DISCUSSION While remaining cogniscent of the complex nature of our patient group, we find that age dependent reductions in CBF oscillations seen using NIRS do not translate to recordings of CBV in the middle cerebral artery in patients with head injury.
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Affiliation(s)
- Philip M Lewis
- Department of Neurosurgery, Alfred Hospital, Prahran, Victoria, Australia
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de Moraes Marchiori LL, de Almeida Rego Filho E, Matsuo T. Hypertension as a factor associated with hearing loss. Braz J Otorhinolaryngol 2007; 72:533-40. [PMID: 17143434 PMCID: PMC9445665 DOI: 10.1016/s1808-8694(15)31001-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Accepted: 03/28/2006] [Indexed: 11/30/2022] Open
Abstract
Aim To identify likely association between blood hypertension and hearing loss. Design: A non-paired case-control study. Setting: Institutional work carried out at Universidade Norte do Paraná, in South Brazil. Material and Method 154 cases and 154 controls, both genders, aged 45 to 64, included in the research after sample estimation. Methodology: Hypertension was verified through blood pressure readings and by a systematized questionnaire about hypertension and the use of medication for blood pressure. Hearing was assessed through tonal threshold audiometrics and audiologic anamneses. Non-conditional logistic regression was used in order to control likely confusion or modification of effect of other variables on interest associations. Results There is a significant association between blood hypertension and hearing loss. Hearing loss in the population under study suggests that hypertension is an accelerating factor of degeneration of the hearing apparatus due to aging. Conclusions The results in this research, through evidence of association between blood hypertension and hearing loss, can allow for an integrated work of cardiologists, nephrologists, otorhinolaryngologists, audiologists and other health professionals concerned with alterations caused by blood hypertension.
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Affiliation(s)
- Luciana Lozza de Moraes Marchiori
- PhD in medicine and Health Sciences, Professor of Speech Therapy and Pharmacy - Norte do Paraná University
- Mailing address: Profª. Drª. Luciana Lozza de Moraes Marchiori - Belo Horizonte 1399/401 86020-060.
| | | | - Tiemi Matsuo
- PhD in Statistics, Professor of the Postgraduate course in Medicine and Health Sciences – Londrina State University. Universidade Norte do Paraná (UNOPAR)
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Abstract
OBJETIVO: investigar a presença de queixa de vertigem em pacientes de meia idade com hipertensão arterial. MÉTODOS: estudo do tipo prospectivo, transversal. Composto por 154 indivíduos de ambos os gêneros com idade de 45 a 64 anos. A hipertensão foi verificada por meio de medição da pressão arterial e de questionário sistematizado sobre hipertensão e uso de medicamentos para pressão arterial. A queixa de vertigem foi verificada por meio de anamnese audiológica. RESULTADOS: pode-se verificar que existe associação significante entre hipertensão arterial e queixa de vertigem. CONCLUSÃO: os resultados da presente pesquisa, por meio da constatação da associação entre hipertensão arterial e queixa de vertigem, servirão de base a profissionais da área de saúde que estão envolvidos com sintomas provenientes da hipertensão arterial.
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Zhang XF, Yang RF, Wang J, Zhao L, Li L, Shen FM, Su DF. Arterial baroreflex function does not influence telomere length in kidney of rats. Acta Pharmacol Sin 2006; 27:1409-16. [PMID: 17049115 DOI: 10.1111/j.1745-7254.2006.00422.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
AIM To investigate the relationship between arterial baroreflex (ABR) function and telomere length in kidney of rats. METHODS Stroke-prone spontaneously hypertensive rats (SHR-SP) and sinoaortic denervated rats (SAD) were used as models with depressed arterial baroreflex. In the first experiments, SHR-SP rats were examined at the age of 24 weeks for both sexes and 40 weeks for female rats. In the second experiments, SAD rats were studied 4 and 35 weeks after SAD operation. Blood pressure was continuously recorded for 4 h in a conscious state. After the determination of baroreflex sensitivity (BRS), the terminal restriction fragment (TRF) of rat kidney was analyzed using Southern blot. RESULTS The TRF length was found shorter in: a) male SHR-SP compared with age-matched female SHR-SP; b) female SHR-SP 40 weeks of age compared with 24 weeks of age; c) in rats 35 weeks after operation compared with rats 4 weeks post operation in both sham-operated and SAD rats. CONCLUSION In SHR-SP, the TRF length did not correlate with BRS. In addition, SAD did not affect TRF length at either 4 or 35 weeks post-surgery. It may be concluded that baroreflex function does not influence the terminal restriction fragment (TRF) length in rats.
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Affiliation(s)
- Xiao-fei Zhang
- Department of Pharmacology, Second Military Medical University, Shanghai 200433, China
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Wang J, Shen FM, Wang MW, Su DF. Effects of nine antihypertensive drugs on blood pressure variability in sinoaortic-denervated rats. Acta Pharmacol Sin 2006; 27:1013-7. [PMID: 16867252 DOI: 10.1111/j.1745-7254.2006.00381.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
AIM The present work was designed to investigate the effects of nine commonly used antihypertensive drugs on blood pressure (BP) and blood pressure variability (BPV) in conscious sinoaortic-denervated (SAD) rats. METHODS Seventy-two SAD rats were randomly divided into nine groups. They were respectively given nifedipine 3 mg/kg, nitrendipine 5 mg/kg, amlodipine 1 mg/kg, clonidine 10 mug/kg, prazosin 0.5 mg/kg, atenolol 20 mg/kg, telmisartan 20 mg/kg, hydrochlorothiazide 40 mg/kg or captopril 50 mg/kg. The drugs were given via a catheter previously implanted into the stomach. BP was recorded for 5 h from 1 h before drug administration to 4 h after drug administration in conscious, freely moving rats. RESULTS It was found that all these nine drugs significantly decreased BP in SAD rats. Six of these drugs (nifedipine, nitrendipine, amlodipine, clonidine, prazosin and atenolol) significantly decreased BPV in SAD rats, but the remaining three drugs did not. Clonidine and atenolol increased the heart period and the others did not. No drugs affected the heart period variability. CONCLUSION Among nine antihypertensive drugs from different classes, calcium antagonists and sympathetic inhibitors decreased BPV in SAD rats.
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Affiliation(s)
- Jin Wang
- Department of Pharmacology, Second Military Medical University, Shanghai 200433, China
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30
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Abstract
OBJETIVO: Identificar possível associação entre hipertensão arterial e perda auditiva. Foi realizado um estudo do tipo caso-controle não pareado, na Universidade Norte do Paraná, no Sul do Brasil. MATERIAL E MÉTODO: 154 casos e 154 controles, de ambos os sexos com idade variando de 45 a 64 anos foram incluídos na pesquisa após o cálculo da amostra. A hipertensão foi verificada por medição da pressão arterial e de questionário sistematizado sobre hipertensão e uso de medicamentos para pressão arterial. A audição foi avaliada por audiometria e anamnese audiológica. A técnica de regressão logística não-condicional foi utilizada com o objetivo de controlar a possível ação de confusão ou modificação de efeito exercida por outras variáveis sobre as associações de interesse. RESULTADOS : Pode-se verificar que existe associação significativa entre hipertensão arterial e presença de perda auditiva e que a perda auditiva observada nesta população sugere que a hipertensão arterial age como fator de aceleração da degeneração do aparelho auditivo proveniente da idade. CONCLUSÕES: Os resultados da presente pesquisa, através da constatação da associação entre hipertensão e perda auditiva, servirão de base a uma integração entre cardiologistas, nefrologistas, otorrinolaringologistas, fonoaudiólogos e outros profissionais da área de com alterações provenientes da hipertensão.
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Visontai Z, Merisch B, Kollai M, Holló G. Increase of carotid artery stiffness and decrease of baroreflex sensitivity in exfoliation syndrome and glaucoma. Br J Ophthalmol 2006; 90:563-7. [PMID: 16488931 PMCID: PMC1857052 DOI: 10.1136/bjo.2005.087908] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AIM To investigate the distensibility of the common carotid artery (CCA), baroreflex sensitivity (BRS) and its relation to plasma homocysteine concentration in exfoliation syndrome or exfoliation glaucoma (XFS/XFG). METHODS Homocysteine concentrations were measured in 30 XFS/XFG patients and 18 age matched controls. In 21 patients and 17 controls the end diastolic diameter of the CCA and pulsatile distension were measured and BRS was calculated. RESULTS There was no significant difference between the groups in sex distribution, age, heart rate, blood pressure, systemic diseases, or medication. In XFS/XFG patients homocysteine concentration was significantly elevated (unpaired t test, p = 0.023), and CCA stiffness was higher (p<0.05), while strain, cross sectional compliance coefficient, distensibility, and BRS were significantly reduced compared to the controls (Mann-Whitney U test, p< or =0.013 for each parameter). In XFS/XFG patients a positive correlation was found between age and plasma homocysteine level (Pearson's correlation, r = 0.490, p = 0.007), and a negative correlation between age and BRS (Kendall's correlation r = -0.374, p = 0.021), as well as between homocysteine concentration and BRS (Kendall's correlation r = -0.377, p = 0.024). No correlation was seen between these variables in the control group. CONCLUSIONS These results suggest a pathological large artery function as well as altered parasympathetic vascular control in XFS/XFG which increases with age and with higher homocysteine concentration.
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Affiliation(s)
- Z Visontai
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary.
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Hayashi K, Miyachi M, Seno N, Takahashi K, Yamazaki K, Sugawara J, Yokoi T, Onodera S, Mesaki N. Fluctuations in carotid arterial distensibility during the menstrual cycle do not influence cardiovagal baroreflex sensitivity. Acta Physiol (Oxf) 2006; 186:103-10. [PMID: 16497187 DOI: 10.1111/j.1748-1716.2005.01505.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM Fluctuations in autonomic nervous functions throughout the menstrual cycle and the underlying mechanism concerning them are not well known. This study was designed to test the hypothesis that fluctuations in cardiovagal baroreflex sensitivity (BRS) throughout the menstrual cycles of young women are due to fluctuations in carotid arterial distensibility. METHODS In eight eumenorrhoeic healthy young women (18-24 years), we determined the variations in the carotid arterial distensibility coefficient (DC; via simultaneous ultrasonography and applanation tonometry), cardiovagal BRS (phase IV of the Valsalva manoeuvre and the sequence method; up- or down-sequence spontaneous BRS), and serum oestradiol and progesterone concentrations at five points in the menstrual cycle (menstrual = M, follicular = F, ovulatory = O, early luteal = EL, and late luteal = LL). RESULTS Serum oestradiol and progesterone levels were consistent with the predicted cycle phases. Carotid arterial DC fluctuated cyclically, increasing significantly from the M (52.4 +/- 4.9 x 10(-3) kPa(-1), mean +/- SE) and F (52.7 +/- 4.4) phases to the O (57.6 +/- 4.4) phase and declining sharply in the EL (46.0 +/- 4.0) and LL (45.1 +/- 3.0) phases (F = 6.37, P < 0.05). Contrary to our prediction, however, cardiovagal BRS by the Valsalva manoeuvre (P = 0.73) or sequence method (up-sequence spontaneous BRS; P = 0.84: down-sequence spontaneous BRS; P = 0.67) did not change significantly during the menstrual cycle. CONCLUSION The results suggest that, although carotid arterial distensibility fluctuates with the changes in ovarian hormone levels that occur during the menstrual cycle, the fluctuations in carotid arterial distensibility do not influence cardiovagal BRS.
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Affiliation(s)
- K Hayashi
- Institute for Human Science and Biomedical Engineering, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan.
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Chesterton LJ, McIntyre CW. The assessment of baroreflex sensitivity in patients with chronic kidney disease: implications for vasomotor instability. Curr Opin Nephrol Hypertens 2005; 14:586-91. [PMID: 16205480 DOI: 10.1097/01.mnh.0000185981.02578.0e] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Autonomic dysfunction is well recognized in chronic kidney disease. The baroreflex arc is an important component of the autonomic nervous system and influences vasodilatation and heart rate in response to information derived from baroreceptors located in the aorta and common carotid arteries. Appropriate regulation of systemic blood pressure is therefore dependent upon the integrity and normal function of the baroreflex arc. Vasomotor instability during haemodialysis has traditionally been identified as a pathophysiological state largely due to the failure of compensatory mechanisms during ultrafiltration. This review article discusses autonomic dysfunction as a key factor contributing to the systemic haemodynamic instability that may occur during dialysis. RECENT FINDINGS Relationships have begun to be established between markers of reduced baroreflex sensitivity and abnormal cardiovascular structure, such as left ventricular dysfunction, left ventricular hypertrophy and arterial stiffness. SUMMARY Pathological relationships between cardiovascular structure and function remain important in the understanding of both haemodynamic instability and cardiovascular mortality in chronic kidney disease patients. Understanding the associations between conventional markers of haemodynamic instability and autonomic function will allow early identification of patients likely to benefit from individualizing dialysis therapy.
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Vigo DE, Guinjoan SM, Scaramal M, Siri LN, Cardinali DP. Wavelet transform shows age-related changes of heart rate variability within independent frequency components. Auton Neurosci 2005; 123:94-100. [PMID: 16293445 DOI: 10.1016/j.autneu.2005.10.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2005] [Revised: 10/11/2005] [Accepted: 10/20/2005] [Indexed: 11/29/2022]
Abstract
Reduction in overall heart rate variability (HRV) associated with aging is determined by a decreased amplitude of heart rate oscillations at all frequency levels, including high frequency (HF) oscillations attributed to respiratory sinus arrhythmia, low frequency (LF) oscillations attributed to Meyer waves and very low frequency (VLF) oscillations of an uncertain origin, presumably linked among others to thermoregulation. However, no studies were conducted to determine whether heart rate oscillations at independent frequency levels show themselves reduced HRV. Wavelet transform was applied to filter specific frequency components of HRV in a sample of younger (21-34 years old) and older (68-85 years old) healthy subjects. HRV indexes were measured within HF, LF and VLF components. The standard deviation of all RR intervals (SDNN) and the square root of the mean squared differences of successive RR intervals (RMSSD) were used as conventional linear time-domain measures. Sample entropy (SampEn) was used as a measure of nonlinear variability. Aged subjects showed lower SDNN at VLF (p < 0.001), LF (p = 0.007) and HF (p < 0.001). Lower RMSSD was observed in older people at VLF (p < 0.001), LF (p = 0.005) and HF (p < 0.001). SampEn was reduced by aging only at VLF level (p < 0.001). In aged people, linear variability was diminished within all frequency components, while nonlinear variability was lower only at VLF level. Preserved central, nonreflex autonomic modulation over the baroreflex control and the central cardiopulmonary coupling might explain this observation. Potential applications of this method include the study of heart rate regulation during sleep in which a complex interaction between the sympathetic and the parasympathetic activity takes place.
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Affiliation(s)
- Daniel E Vigo
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay, Argentina
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Parati G, Lantelme P. Mechanical and neural components of the cardiac baroreflex: new insights into complex physiology. J Hypertens 2005; 23:717-20. [PMID: 15775773 DOI: 10.1097/01.hjh.0000163137.59341.c3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Reneman RS, Meinders JM, Hoeks APG. Non-invasive ultrasound in arterial wall dynamics in humans: what have we learned and what remains to be solved. Eur Heart J 2005; 26:960-6. [PMID: 15764612 DOI: 10.1093/eurheartj/ehi177] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In the past decades, non-invasive vascular ultrasound has substantially improved our insights into artery wall dynamics under normal circumstances and in disease. Although we have learned a lot, the methods in use are subject to improvement. In this review, we discuss the most important achievements in non-invasive assessment of dynamic artery wall properties in humans with emphasis on the clinical relevance of the observations. Special attention will be paid to the changes observed in aging, and in essential and borderline hypertension, because the loss of compliance (i.e. the ability to store volume thereby reducing pressure increases during ejection) of the elastic arteries in the elderly and in these patients possibly has consequences on their management. The changes in dynamic artery wall properties in diabetes and atherosclerosis are briefly discussed as well. A new approach to the determination of baroreceptor sensitivity, using artery stretch as input, is presented. The review starts with a description of the parameters most commonly used to describe dynamic artery wall properties and of the techniques employed to assess these parameters. The problems encountered in these assessments and the possible solutions to these problems are addressed as well.
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Affiliation(s)
- Robert S Reneman
- Department of Physiology, Cardiovascular Research Institute Maastricht, University of Maastricht, PO Box 616, 6200 MD Maastricht, The Netherlands.
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