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Li P, Gao C, Yu L, Gao L, Cai R, Bennett DA, Schneider JA, Buchman AS, Hu K. Delineating cognitive resilience using fractal regulation: Cross-sectional and longitudinal evidence from the Rush Memory and Aging Project. Alzheimers Dement 2024; 20:3203-3210. [PMID: 38497429 PMCID: PMC11095481 DOI: 10.1002/alz.13747] [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: 12/01/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 03/19/2024]
Abstract
INTRODUCTION Degradation of fractal patterns in actigraphy independently predicts dementia risk. Such observations motivated the study to understand the role of fractal regulation in the context of neuropathologies. METHODS We examined associations of fractal regulation with neuropathologies and longitudinal cognitive changes in 533 older participants who were followed annually with actigraphy and cognitive assessments until death with brain autopsy performed. Two measures for fractal patterns were extracted from actigraphy, namely, α1 (representing the fractal regulation at time scales of <90 min) and α2 (for time scales 2 to 10 h). RESULTS We found that larger α1 was associated with lower burdens of Lewy body disease or cerebrovascular disease pathologies; both α1 and α2 were associated with cognitive decline. They explained an additional significant portion of the variance in the rate of cognitive decline above and beyond neuropathologies. DISCUSSION Fractal patterns may be used as a biomarker for cognitive resilience against dementia-related neuropathologies.
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Affiliation(s)
- Peng Li
- Department of AnesthesiaCritical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Medical Biodynamics Program, Division of Sleep and Circadian DisordersBrigham and Women's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
- Broad Institute of MIT and HarvardCambridgeMassachusettsUSA
| | - Chenlu Gao
- Department of AnesthesiaCritical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Medical Biodynamics Program, Division of Sleep and Circadian DisordersBrigham and Women's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
- Broad Institute of MIT and HarvardCambridgeMassachusettsUSA
| | - Lei Yu
- Rush Alzheimer's Disease CenterRush University Medical CenterChicagoIllinoisUSA
| | - Lei Gao
- Department of AnesthesiaCritical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Medical Biodynamics Program, Division of Sleep and Circadian DisordersBrigham and Women's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
- Broad Institute of MIT and HarvardCambridgeMassachusettsUSA
| | - Ruixue Cai
- Department of AnesthesiaCritical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Medical Biodynamics Program, Division of Sleep and Circadian DisordersBrigham and Women's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - David A. Bennett
- Rush Alzheimer's Disease CenterRush University Medical CenterChicagoIllinoisUSA
| | - Julie A. Schneider
- Rush Alzheimer's Disease CenterRush University Medical CenterChicagoIllinoisUSA
| | - Aron S. Buchman
- Rush Alzheimer's Disease CenterRush University Medical CenterChicagoIllinoisUSA
| | - Kun Hu
- Department of AnesthesiaCritical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Medical Biodynamics Program, Division of Sleep and Circadian DisordersBrigham and Women's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
- Broad Institute of MIT and HarvardCambridgeMassachusettsUSA
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Sato T, Aoki T, Ito Y, Oishi K, Fujishima M, Okumura E, Ishii K. Effects of continuous supplementation of Acanthopanax senticosus Harms on the cardiac autonomic function of community-dwelling elderly individuals during resting and standing tests: a randomized controlled trial. Front Cardiovasc Med 2024; 11:1336676. [PMID: 38525193 PMCID: PMC10957529 DOI: 10.3389/fcvm.2024.1336676] [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: 11/17/2023] [Accepted: 02/26/2024] [Indexed: 03/26/2024] Open
Abstract
Background Cardiac autonomic function (CAF) decreases with aging, and Acanthopanax senticosus Harms (ASH) consumption reportedly induces anti-stress effects. This study aimed to assess the effect of continuous supplementation of ASH on CAF during resting and standing tests in the elderly population. Methods This double-blind, randomized controlled trial was conducted in the morning in a laboratory setting and was carried out between June 2017 and July 2017 at Kambaikan, Doshisha University (Karasuma-higashi-iru, Imadegawa-dori, Kamigyo-ku, Kyoto 602-8580, Japan). In total, 28 community-dwelling elderly individuals (mean ± standard deviation = 72.5 ± 4.5 years) were included. Each subject was instructed to consume ASH or placebo supplements twice daily for 4 weeks. An autonomic reflex orthostatic tolerance recorder was used to measure CAF in pre- and post-intervention phases. Parameters were measured in a seated position and included coefficient of variation of R-R intervals (CVRR), low frequency (LF), high frequency (HF), LF/HF ratio, blood pressure, and heart rate (HR). Changes in each parameter were evaluated before and after standing. All parameters were defined as the difference between the mean value obtained in a standing position for 2 min and that obtained in a 2-min seated position. Results A two-way analysis of variance revealed a significant group-time interaction effect on CVRR, HF, and ΔLF/HF ratio. Following the intervention, CVRR, HF, LF/HF ratio, systolic blood pressure (SBP), HR, ΔLF/HF ratio, ΔSBP, and ΔHR improved significantly in the ASH group only. Conclusions Four-week supplementation of ASH improved CAF in community-dwelling elderly individuals during resting and standing tests. Clinical Trial Registration https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000031218, UMIN Clinical Trials Registry (UMIN000027251).
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Affiliation(s)
- Takeru Sato
- Graduate School of Health and Sports Science, Doshisha University, Kyo-Tanabe, Japan
| | - Takumi Aoki
- Faculty of Education, Miyagi Gakuin Women’s University, Sendai, Japan
| | - Yuki Ito
- College of Life and Health Sciences, Chubu University, Kasugai, Japan
| | - Kan Oishi
- Graduate School of Health and Sports Science, Doshisha University, Kyo-Tanabe, Japan
| | | | | | - Kojiro Ishii
- Faculty of Health and Sports Science, Doshisha University, Kyo-Tanabe, Japan
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Lozano WM, Ortiz-Guzmán JE, Arias-Mutis O, Bizy A, Genovés P, Such-Miquel L, Alberola A, Chorro FJ, Zarzoso M, Calvo CJ. Modifications of long-term heart rate variability produced in an experimental model of diet-induced metabolic syndrome. Interface Focus 2023; 13:20230030. [PMID: 38106920 PMCID: PMC10722215 DOI: 10.1098/rsfs.2023.0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/13/2023] [Indexed: 12/19/2023] Open
Abstract
Metabolic syndrome (MetS) has been linked to a higher prevalence of cardiac arrhythmias, the most frequent being atrial fibrillation, but the mechanisms are not well understood. One possible underlying mechanism may be an abnormal modulation of autonomic nervous system activity, which can be quantified by analysing heart rate variability (HRV). Our aim was to investigate the modifications of long-term HRV in an experimental model of diet-induced MetS to identify the early changes in HRV and the link between autonomic dysregulation and MetS components. NZW rabbits were randomly assigned to control (n = 10) or MetS (n = 10) groups, fed 28 weeks with high-fat, high-sucrose diet. 24-hour recordings were used to analyse HRV at week 28 using time-domain, frequency-domain and nonlinear analyses. Time-domain analysis showed a decrease in RR interval and triangular index (Ti). In the frequency domain, we found a decrease in the low frequency band. Nonlinear analyses showed a decrease in DFA-α1 and DFA-α2 (detrended fluctuations analysis) and maximum multiscale entropy. The strongest association between HRV parameters and markers of MetS was found between Ti and mean arterial pressure, and Ti and left atrial diameter, which could point towards the initial changes induced by the autonomic imbalance in MetS.
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Affiliation(s)
- W. M. Lozano
- Department of Physiology, Universitat de València, Valencia, Comunitat Valenciana, Spain
- School of Physiotherapy, Universidad Industrial de Santander, Bucaramanga, Santander, Colombia
| | - J. E. Ortiz-Guzmán
- Department of Physiology, Universitat de València, Valencia, Comunitat Valenciana, Spain
| | - O. Arias-Mutis
- Department of Biomedical Sciences, CEU Cardenal Herrera, Moncada, Valenciana, Spain
- Health Research Institute - Instituto de Investigación Sanitaria del Hospital Clínico Universitario de Valencia (INCLIVA), Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBER-CV), Madrid, Spain
| | - A. Bizy
- Department of Biomedical Sciences, CEU Cardenal Herrera, Moncada, Valenciana, Spain
| | - P. Genovés
- Department of Physiology, Universitat de València, Valencia, Comunitat Valenciana, Spain
| | - L. Such-Miquel
- Department of Physiotherapy, Universitat de València, València, Spain
| | - A. Alberola
- Department of Physiology, Universitat de València, Valencia, Comunitat Valenciana, Spain
| | - F. J. Chorro
- Health Research Institute - Instituto de Investigación Sanitaria del Hospital Clínico Universitario de Valencia (INCLIVA), Valencia, Spain
- Department of Medicine, Universitat de València, València, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBER-CV), Madrid, Spain
| | - M. Zarzoso
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBER-CV), Madrid, Spain
- Department of Physiotherapy, Universitat de València, València, Spain
| | - C. J. Calvo
- Department of Physiology, Universitat de València, Valencia, Comunitat Valenciana, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBER-CV), Madrid, Spain
- CSIC-UPV, Instrumentation for Molecular Imaging Technologies Research Institute (I3M), Universitat Politècnica de València, València, Spain
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Nardelli M, Citi L, Barbieri R, Valenza G. Characterization of autonomic states by complex sympathetic and parasympathetic dynamics. Physiol Meas 2023; 44. [PMID: 36787644 DOI: 10.1088/1361-6579/acbc07] [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: 11/15/2022] [Accepted: 02/14/2023] [Indexed: 02/16/2023]
Abstract
Assessment of heartbeat dynamics provides a promising framework for non-invasive monitoring of cardiovascular and autonomic states. Nevertheless, the non-specificity of such measurements among clinical populations and healthy conditions associated with different autonomic states severely limits their applicability and exploitation in naturalistic conditions. This limitation arises especially when pathological or postural change-related sympathetic hyperactivity is compared to autonomic changes across age and experimental conditions. In this frame, we investigate the intrinsic irregularity and complexity of cardiac sympathetic and vagal activity series in different populations, which are associated with different cardiac autonomic dynamics. Sample entropy, fuzzy entropy, and distribution entropy are calculated on the recently proposed sympathetic and parasympathetic activity indices (SAI and PAI) series, which are derived from publicly available heartbeat series of congestive heart failure patients, elderly and young subjects watching a movie in the supine position, and healthy subjects undergoing slow postural changes. Results show statistically significant differences between pathological/old subjects and young subjects in the resting state and during slow tilt, with interesting trends in SAI- and PAI-related entropy values. Moreover, while CHF patients and healthy subjects in upright position show the higher cardiac sympathetic activity, elderly and young subjects in resting state showed higher vagal activity. We conclude that quantification of intrinsic cardiac complexity from sympathetic and vagal dynamics may provide new physiology insights and improve on the non-specificity of heartbeat-derived biomarkers.
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Affiliation(s)
- Mimma Nardelli
- Bioengineering and Robotics Research Centre E. Piaggio and Dipartimento di Ingegneria dell'Informazione, University of Pisa, Italy
| | - Luca Citi
- School of Computer Science and Electronic Engineering, University of Essex, United Kingdom
| | - Riccardo Barbieri
- Department of Electronics, Informatics and Bioengineering, Politecnico di Milano, Milano, Italy
| | - Gaetano Valenza
- Bioengineering and Robotics Research Centre E. Piaggio and Dipartimento di Ingegneria dell'Informazione, University of Pisa, Italy
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Levin MD, Cathey BM, Smith K, Osgood S, Raja N, Fu YP, Kozel BA. Heart Rate Variability Analysis May Identify Individuals With Williams-Beuren Syndrome at Risk of Sudden Death. JACC Clin Electrophysiol 2023; 9:359-370. [PMID: 36752464 PMCID: PMC10065881 DOI: 10.1016/j.jacep.2022.10.010] [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: 12/23/2021] [Revised: 09/28/2022] [Accepted: 10/03/2022] [Indexed: 12/02/2022]
Abstract
BACKGROUND Williams-Beuren syndrome (WBS) (Online Mendelian Inheritance in Man #194050) is a rare genetic multisystem disorder resulting from a chromosomal microdeletion at 7q11.23. The condition is characterized by distinct facies, intellectual disability, and supravalvar aortic stenosis. Those with WBS have an increased risk of sudden death, but mechanisms underlying this phenotype are incompletely understood. OBJECTIVES The aim of this study was to quantify and compare autonomic activity as reflected by heart rate variability (HRV) measures in a cohort of individuals with WBS (n = 18) and age- and sex-matched control subjects (n = 18). METHODS We performed HRV analysis on 24-hour electrocardiography recordings using nonlinear, time and frequency domain analyses on a cohort of subjects with WBS and age- and sex-matched control subjects enrolled in a prospective cross-sectional study designed to characterize WBS disease natural history. RESULTS WBS subjects demonstrated diminished HRV (reflected by the SD of the NN intervals [P = 0.0001], SD of the average NN interval for 5-minute intervals over 24 hours [P < 0.0001], average of the 5-minute SDs of NN intervals for 24 hours [P = 0.0002], root mean square of successive differences of NN intervals [P = 0.0004], short axis of the Poincaré plot (SD1) [P < 0.0001], and long axis of the Poincaré plot [P < 0.0001]) and indirect markers of parasympathetic activity (reflected by the percent of NN intervals different from previous by 50% or more of local average [P < 0.0007], root mean square of successive differences of NN intervals [P = 0.0004], natural log high-frequency power [P = 0.0038], and SD1 [P < 0.0001]). Additional parameters were also significantly different, including natural log very low-frequency power (decreased; P = 0.0002), natural log low-frequency power (decreased; P = 0.0024), and SD1 divided by the long axis of the Poincaré plot (decreased; P < 0.0001). CONCLUSIONS Individuals with WBS demonstrate significant HRV abnormalities consistent with diminished autonomic reserve. Future studies will be needed to determine the relationship between autonomic dysregulation observed and sudden death risk seen in these patients. (Impact of Elastin Mediated Vascular Stiffness on End Organs; NCT02840448).
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Affiliation(s)
- Mark D Levin
- Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
| | - Brianna M Cathey
- Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; School of Engineering Medicine, Texas A&M University, College Station, Texas, USA
| | - Kevin Smith
- Nursing Department, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Sharon Osgood
- Office of the Clinical Director, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Neelam Raja
- Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Yi-Ping Fu
- Office of Biostatistics Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Beth A Kozel
- Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
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Goswami I, Maguire B, Chau V, Tam EW, Pinchefsky E, Whitney R, Wilson D, Miller SP, Cortez MA. Early transient dysautonomia predicts the risk of infantile epileptic spasm syndrome onset: A prospective cohort study. Front Neurol 2022; 13:1090155. [PMID: 36619920 PMCID: PMC9815183 DOI: 10.3389/fneur.2022.1090155] [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: 11/05/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
Background Infantile epileptic spasm syndrome (IESS) is an age-dependent epileptic encephalopathy with a significant risk of developmental regression. This study investigates the association between heart rate variability (HRV) in infants at risk of IESS and the clinical onset of IESS. Methods Sixty neonates at risk of IESS were prospectively followed from birth to 12 months with simultaneous electroencephalogram (EEG) and electrocardiogram recordings for 60 min at every 2-month interval. HRV metrics were calculated from 5 min time-epoch during sleep including frequency domain measures, Poincare analysis including cardiac vagal index (CVI) and cardiac sympathetic index (CSI), and detrended fluctuation analysis (DFA α1, DFA α2). To assess the effect of each HRV metric at the 2-month baseline on the time until the first occurrence of either hypsarrhythmia on EEG and/or clinical spasm, univariate cox-proportional hazard models were fitted for each HRV metric. Results Infantile epileptic spasm syndrome was diagnosed in 20/60 (33%) of the cohort in a 12-month follow-up and 3 (5%) were lost to follow-up. The median age of developing hypsarrhythmia was 25 (7-53) weeks and clinical spasms at 24 (8-40) weeks. Three (5%) patients had clinical spasms without hypsarrhythmia, and 5 (8%) patients had hypsarrhythmia before clinical spasms at the initial presentation. The infants with high CSI (hazard ratio 2.5, 95% CI 1.2-5.2, P = 0.01) and high DFA α1 (hazard ratio 16, 95% CI 1.1-240, P = 0.04) at 2 months were more likely to develop hypsarrhythmia by the first year of age. There was a trend toward decreasing CSI and DFA α1 and increasing CVI in the first 8 months of age. Conclusion Our data suggest that relative sympathetic predominance at an early age of 2 months may be a potential predictor for developing IESS. Hence, early HRV patterns may provide valuable prognostic information in children at risk of IESS allowing early detection and optimization of cognitive outcomes. Whether early intervention to restore sympathovagal balance per se would provide clinical benefit must be addressed by future studies.
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Affiliation(s)
- Ipsita Goswami
- Department of Pediatrics, Divisions of Neonatology, McMaster Children's Hospital, McMaster University, Hamilton, ON, Canada,*Correspondence: Ipsita Goswami ✉
| | - Bryan Maguire
- Child Health Evaluative Sciences Research Program, Toronto and Cancer Care Ontario, The Hospital for Sick Children, SickKids Research Institute, Toronto, ON, Canada
| | - Vann Chau
- Department of Pediatrics, Divisions of Neurology, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada,Department of Pediatrics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Emily W. Tam
- Department of Pediatrics, Divisions of Neurology, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada,Department of Pediatrics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Elana Pinchefsky
- Department of Pediatrics, Division of Neurology, Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Montreal, QC, Canada
| | - Robyn Whitney
- Department of Pediatrics, Divisions of Neurology, McMaster Children's Hospital, McMaster University, Hamilton, ON, Canada
| | - Diane Wilson
- Department of Pediatrics, Divisions of Neonatology, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Steven P. Miller
- Department of Pediatrics, Divisions of Neurology, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada,Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Miguel A. Cortez
- Department of Pediatrics, Divisions of Neurology, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada,Department of Pediatrics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada,Miguel A. Cortez ✉
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Jarczok MN, Weimer K, Braun C, Williams DP, Thayer JF, Gündel HO, Balint EM. Heart rate variability in the prediction of mortality: A systematic review and meta-analysis of healthy and patient populations. Neurosci Biobehav Rev 2022; 143:104907. [DOI: 10.1016/j.neubiorev.2022.104907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 10/03/2022] [Accepted: 10/04/2022] [Indexed: 11/07/2022]
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Lan JY, Shieh JS, Yeh JR, Fan SZ. Fractal Properties of Heart Rate Dynamics: A New Biomarker for Anesthesia-Biphasic Changes in General Anesthesia and Decrease in Spinal Anesthesia. SENSORS (BASEL, SWITZERLAND) 2022; 22:9258. [PMID: 36501959 PMCID: PMC9740393 DOI: 10.3390/s22239258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/10/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
Processed electroencephalogram (EEG) has been considered a useful tool for measuring the depth of anesthesia (DOA). However, because of its inability to detect the activities of the brain stem and spinal cord responsible for most of the vital signs, a new biomarker for measuring the multidimensional activities of the central nervous system under anesthesia is required. Detrended fluctuation analysis (DFA) is a new technique for detecting the scaling properties of nonstationary heart rate (HR) behavior. This study investigated the changes in fractal properties of heart rate variability (HRV), a nonlinear analysis, under intravenous propofol, inhalational desflurane, and spinal anesthesia. We compared the DFA method with traditional spectral analysis to evaluate its potential as an alternative biomarker under different levels of anesthesia. Eighty patients receiving elective procedures were randomly allocated different anesthesia. HRV was measured with spectral analysis and DFA short-term (4-11 beats) scaling exponent (DFAα1). An increase in DFAα1 followed by a decrease at higher concentrations during propofol or desflurane anesthesia is observed. Spinal anesthesia decreased the DFAα1 and low-/high-frequency ratio (LF/HF ratio). DFAα1 of HRV is a sensitive and specific method for distinguishing changes from baseline to anesthesia state. The DFAα1 provides a potential real-time biomarker to measure HRV as one of the multiple dimensions of the DOA.
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Affiliation(s)
- Jheng-Yan Lan
- Department of Anesthesiology, Taipei Veterans General Hospital, Yuli Branch, Hualian 98142, Taiwan
| | - Jiann-Shing Shieh
- Department of Mechanical Engineering, Yuan Ze University, Taoyuan 320, Taiwan
| | - Jia-Rong Yeh
- Department of Anesthesiology, National Taiwan University Hospital, Taipei 10002, Taiwan
| | - Shou-Zen Fan
- Department of Anesthesiology, National Taiwan University Hospital, Taipei 10002, Taiwan
- Department of Anesthesiology, En Chu Kong Hospital, New Taipei City 237, Taiwan
- College of Medicine, National Taiwan University, Taipei 10002, Taiwan
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Nayir S, Lacour SP, Kucera JP. Active force generation contributes to the complexity of spontaneous activity and to the response to stretch of murine cardiomyocyte cultures. J Physiol 2022; 600:3287-3312. [PMID: 35679256 PMCID: PMC9541716 DOI: 10.1113/jp283083] [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: 03/10/2022] [Accepted: 06/01/2022] [Indexed: 11/17/2022] Open
Abstract
Abstract Cardiomyocyte cultures exhibit spontaneous electrical and contractile activity, as in a natural cardiac pacemaker. In such preparations, beat rate variability exhibits features similar to those of heart rate variability in vivo. Mechanical deformations and forces feed back on the electrical properties of cardiomyocytes, but it is not fully elucidated how this mechano‐electrical interplay affects beating variability in such preparations. Using stretchable microelectrode arrays, we assessed the effects of the myosin inhibitor blebbistatin and the non‐selective stretch‐activated channel blocker streptomycin on beating variability and on the response of neonatal or fetal murine ventricular cell cultures against deformation. Spontaneous electrical activity was recorded without stretch and upon predefined deformation protocols (5% uniaxial and 2% equibiaxial strain, applied repeatedly for 1 min every 3 min). Without stretch, spontaneous activity originated from the edge of the preparations, and its site of origin switched frequently in a complex manner across the cultures. Blebbistatin did not change mean beat rate, but it decreased the spatial complexity of spontaneous activity. In contrast, streptomycin did not exert any manifest effects. During the deformation protocols, beat rate increased transiently upon stretch but, paradoxically, also upon release. Blebbistatin attenuated the response to stretch, whereas this response was not affected by streptomycin. Therefore, our data support the notion that in a spontaneously firing network of cardiomyocytes, active force generation, rather than stretch‐activated channels, is involved mechanistically in the complexity of the spatiotemporal patterns of spontaneous activity and in the stretch‐induced acceleration of beating.
![]() Key points Monolayer cultures of cardiac cells exhibit spontaneous electrical and contractile activity, as in a natural cardiac pacemaker. Beating variability in these preparations recapitulates the power‐law behaviour of heart rate variability in vivo. However, the effects of mechano‐electrical feedback on beating variability are not yet fully understood. Using stretchable microelectrode arrays, we examined the effects of the contraction uncoupler blebbistatin and the non‐specific stretch‐activated channel blocker streptomycin on beating variability and on stretch‐induced changes of beat rate. Without stretch, blebbistatin decreased the spatial complexity of beating variability, whereas streptomycin had no effects. Both stretch and release increased beat rate transiently; blebbistatin attenuated the increase of beat rate upon stretch, whereas streptomycin had no effects. Active force generation contributes to the complexity of spatiotemporal patterns of beating variability and to the increase of beat rate upon mechanical deformation. Our study contributes to the understanding of how mechano‐electrical feedback influences heart rate variability.
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Affiliation(s)
- Seyma Nayir
- Department of Physiology, University of Bern, Bern, Switzerland
| | | | - Jan P Kucera
- Department of Physiology, University of Bern, Bern, Switzerland
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Moulder RG, Daniel KE, Teachman BA, Boker SM. Tangle: A metric for quantifying complexity and erratic behavior in short time series. Psychol Methods 2022; 27:82-98. [PMID: 33507767 PMCID: PMC8552416 DOI: 10.1037/met0000386] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Temporal complexity refers to qualities of a time series that are emergent, erratic, or not easily described by linear processes. Quantifying temporal complexity within a system is key to understanding the time based dynamics of said system. However, many current methods of complexity quantification are not widely used in psychological research because of their technical difficulty, computational intensity, or large number of required data samples. These requirements impede the study of complexity in many areas of psychological science. A method is presented, tangle, which overcomes these difficulties and allows for complexity quantification in relatively short time series, such as those typically obtained from psychological studies. Tangle is a measure of how dissimilar a given process is from simple periodic motion. Tangle relies on the use of a three-dimensional time delay embedding of a one-dimensional time series. This embedding is then iteratively scaled and premultiplied by a modified upshift matrix until a convergence criterion is reached. The efficacy of tangle is shown on five mathematical time series and using emotional stability, anxiety time series data obtained from 65 socially anxious participants over a 5-week period, and positive affect time series derived from a single participant who experienced a major depression episode during measurement. Simulation results show tangle is able to distinguish between different complex temporal systems in time series with as few as 50 samples. Tangle shows promise as a reliable quantification of irregular behavior of a time series. Unlike many other complexity quantification metrics, tangle is technically simple to implement and is able to uncover meaningful information about time series derived from psychological research studies. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
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Stachel G, Abdel-Wahab M, de Waha-Thiele S, Desch S, Feistritzer HJ, Kitamura M, Farhan S, Eitel I, Kurz T, Thiele H. Fractal dimension of the aortic annulus: a novel predictor of paravalvular leak after transcatheter aortic valve implantation. Int J Cardiovasc Imaging 2022; 38:2469-2478. [PMID: 36434335 PMCID: PMC9700572 DOI: 10.1007/s10554-022-02657-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 05/22/2022] [Indexed: 12/14/2022]
Abstract
To evaluate the prognostic relevance of aortic annulus (AA) and left ventricular outflow tract (LVOT) Fractal dimension (FD). FD is a mathematical concept that describes geometric complexity of a structure and has been shown to predict adverse outcomes in several contexts. Computed tomography (CT) scans from the SOLVE-TAVI trial, which, in a 2 × 2 factorial design, randomized 447 patients to TAVI with the balloon-expandable Edwards Sapien 3 or the self-expanding Medtronic Evolut R, and conscious sedation or general anesthesia, were analyzed semi-automatically with a custom-built software to determine border of AA and LVOT. FD was measured by box counting using grid calibers between 0.8 and 6.75 mm and was compared between patients with none/trivial and mild/moderate paravalvular regurgitation (PVR). Overall, 122 patients had CT scans sufficient for semi-automatic PVR in 30-day echocardiography. PVR was none in 65(53.3%) patients, trace in 9(7.4%), mild in 46(37.7%), moderate in 2(1.6%) and severe in 0 patients. FD determined in diastolic images was significantly higher in patients with mild/moderate PVR (1.0558 ± 0.0289 vs. 1.0401 ± 0.0284, p = 0.017). Annulus eccentricity was the only conventional measure of AA and LVOT geometry significantly correlated to FD (R = 0.337, p < 0.01). Area under the curve (AUC) of diastolic annular FD for prediction of mild/moderate PVR in ROC analysis was 0.661 (0.542-0.779, p = 0.014). FD shows promise in prediction of PVR after TAVI. Further evaluation using larger patient numbers and refined algorithms to better understand its predictive performance is warranted.Trial Registration: www.clinicaltrials.gov , identifier: NCT02737150, date of registration: 13.04.2016.
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Affiliation(s)
- Georg Stachel
- Department of Internal Medicine/Cardiology and Leipzig Heart Institute, Heart Center Leipzig at University of Leipzig, Leipzig, Germany
| | - Mohamed Abdel-Wahab
- Department of Internal Medicine/Cardiology and Leipzig Heart Institute, Heart Center Leipzig at University of Leipzig, Leipzig, Germany
| | - Suzanne de Waha-Thiele
- Department of Cardiac Surgery, Heart Center Leipzig at University of Leipzig, Strümpellstr. 39, 04289 Leipzig, Germany
| | - Steffen Desch
- Department of Internal Medicine/Cardiology and Leipzig Heart Institute, Heart Center Leipzig at University of Leipzig, Leipzig, Germany ,University Clinic Schleswig-Holstein, University Heart Center Luebeck, Lübeck, Germany
| | - Hans-Josef Feistritzer
- Department of Internal Medicine/Cardiology and Leipzig Heart Institute, Heart Center Leipzig at University of Leipzig, Leipzig, Germany
| | - Mitsunobu Kitamura
- Department of Internal Medicine/Cardiology and Leipzig Heart Institute, Heart Center Leipzig at University of Leipzig, Leipzig, Germany
| | - Serdar Farhan
- The Zena and Michael A. Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - Ingo Eitel
- University Clinic Schleswig-Holstein, University Heart Center Luebeck, Lübeck, Germany ,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Luebeck/Kiel, Lübeck, Germany
| | - Thomas Kurz
- University Clinic Schleswig-Holstein, University Heart Center Luebeck, Lübeck, Germany
| | - Holger Thiele
- Department of Internal Medicine/Cardiology and Leipzig Heart Institute, Heart Center Leipzig at University of Leipzig, Leipzig, Germany
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Cardiorespiratory optimal point during exercise testing and sudden cardiac death: A prospective cohort study. Prog Cardiovasc Dis 2021; 68:12-18. [PMID: 34597617 DOI: 10.1016/j.pcad.2021.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 09/04/2021] [Indexed: 01/02/2023]
Abstract
BACKGROUND Cardiorespiratory optimal point (COP) during exercise, a potentially useful submaximal cardiopulmonary exercise testing (CPET) variable, may be an independent risk factor for cardiovascular disease outcomes. However, the relationship of COP with risk of sudden cardiac death (SCD) has not been previously investigated. We sought to evaluate the association between COP during exercise and SCD risk and determine whether COP improves SCD risk prediction. METHODS COP, the minimum value of the ventilatory equivalent for oxygen (VE/VO2) in a given minute of a CPET, was ascertained in 2190 men who underwent clinical exercise testing. Hazard ratios (HRs) (95% confidence intervals [CIs]) and measures of risk discrimination for SCD were calculated. RESULTS A total of 240 SCDs death occurred during a median follow-up of 28.8 years. COP was linearly associated with SCD in a dose-response manner. In a multivariable model comprising several established and emerging CVD risk factors, the HR (95% CI) for SCD was 2.51 (1.36-4.62) per standard deviation increase in COP. This was minimally attenuated to 2.36 (1.27-4.37) on further adjustment for high sensitivity C-reactive protein. The association did not vary importantly in several relevant clinical subgroups. Addition of COP to a SCD risk score was associated with a C-index change of 0.0086 (0.0005 to 0.0167; p = .038) and difference in -2 log likelihood (p = .017). CONCLUSIONS COP during exercise is strongly, inversely and independently associated with SCD in a graded fashion. COP during exercise may potentially be used for the prediction of the long-term risk for SCD beyond established CVD risk factors.
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Wu S, Chen M, Wang J, Shi B, Zhou Y. Association of Short-Term Heart Rate Variability With Breast Tumor Stage. Front Physiol 2021; 12:678428. [PMID: 34566672 PMCID: PMC8461241 DOI: 10.3389/fphys.2021.678428] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
Cardiac autonomic modulation, assessed by heart rate variability (HRV), is associated with tumor pathogenesis and development as well as invasion and metastasis. This study aimed to examine this association in breast cancer (BC) patients. A total of 133 patients (average age 49.2years) with BC or benign breast tumors were divided into three groups: benign group, early-stage group, and advanced-stage group. About 5-min resting ECG was collected for the analysis of linear and nonlinear HRV parameters. Multiple logistic regression models were performed to test the independent contribution of HRV to breast tumor stage. The advanced-stage group had significantly reduced HRV compared to the benign and early-stage groups. In particular, for each 1-SD increase in SD2, SD of normal-to-normal intervals, very-low frequency, total power, and low frequency, the odds of having advanced staging decreased by 69.3, 64.3, 58.3, 53.3, and 65.9%, respectively. These associations were independent of age, body mass index, mean heart rate (HR), and respiratory rate (RR). These findings suggest an association between HRV and breast tumor stage, and HRV parameters may help construct an effective early diagnostic and clinical prognostic model.
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Affiliation(s)
- Shuang Wu
- Department of Radiation Oncology, First Affiliated Hospital, Bengbu Medical College, Bengbu, China
| | - Man Chen
- Department of Radiation Oncology, First Affiliated Hospital, Bengbu Medical College, Bengbu, China
| | - Jingfeng Wang
- School of Medical Imaging, Bengbu Medical College, Bengbu, China.,Anhui Key Laboratory of Computational Medicine and Intelligent Health, Bengbu Medical College, Bengbu, China
| | - Bo Shi
- School of Medical Imaging, Bengbu Medical College, Bengbu, China.,Anhui Key Laboratory of Computational Medicine and Intelligent Health, Bengbu Medical College, Bengbu, China
| | - Yufu Zhou
- Department of Radiation Oncology, First Affiliated Hospital, Bengbu Medical College, Bengbu, China
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14
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Fagundes CP, Wu EL. Biological mechanisms underlying widowhood's health consequences: Does diet play a role? COMPREHENSIVE PSYCHONEUROENDOCRINOLOGY 2021; 7:100058. [PMID: 35757059 PMCID: PMC9216459 DOI: 10.1016/j.cpnec.2021.100058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 05/01/2021] [Accepted: 05/02/2021] [Indexed: 11/29/2022] Open
Abstract
The loss of a spouse is a highly stressful event that puts older adults at increased risk for morbidity and mortality. The risk is highest in the first year to 18 months post-loss; nevertheless, widow(er)s, in general, are at heightened risk of cardiovascular disease (CVD) related morbidity and mortality, and to a lesser extent, non-CVD related morbidity and mortality. The primary goal of this article is to argue for a perspective that considers diet and emotion-induced autonomic, neuroendocrine, and immune dysregulation, in unison, to understand the mechanisms underlying morbidity and mortality in early widowhood. Toward this end, we first summarize our previously published work, as well as work from other investigatory teams, showing that compared with those who were not bereaved, widow(er)s have higher levels of pro-inflammatory cytokine production and more dysregulated autonomic and neuroendocrine activity than non-widow(er)s, independent of health behaviors such as diet. We highlight that a major gap in our current understanding of the biobehavioral mechanisms that underlie the widowhood effect is the role of diet and hypothesize that the adverse health impact of grief and associated negative emotions and diet may be more than additive. Therefore, we propose that diet may be a pathway by which widow(er)s are at higher CVD risk requiring further investigation. Losing a spouse is highly stressful event; it increases one’s risk for morbidity and mortality, especially within the first 18 months post-loss. Widow(er)s are at risk of cardiovascular disease (CVD)- and non-CVD related morbidity and mortality. The role of diet is a major gap in our understanding of the biobehavioral mechanisms that underlie the widowhood effect. Diet clearly impacts CVD, and widow(er)s' eating habits are altered for at least the first two years post-loss. The adverse health impact of stress and diet may be more than additive; it may be synergistic.
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15
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Hansrivijit P, Chen YJ, Lnu K, Trongtorsak A, Puthenpura MM, Thongprayoon C, Bathini T, Mao MA, Cheungpasitporn W. Prediction of mortality among patients with chronic kidney disease: A systematic review. World J Nephrol 2021; 10:59-75. [PMID: 34430385 PMCID: PMC8353601 DOI: 10.5527/wjn.v10.i4.59] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/11/2021] [Accepted: 07/23/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Chronic kidney disease (CKD) is a common medical condition that is increasing in prevalence. Existing published evidence has revealed through regression analyses that several clinical characteristics are associated with mortality in CKD patients. However, the predictive accuracies of these risk factors for mortality have not been clearly demonstrated. AIM To demonstrate the accuracy of mortality predictive factors in CKD patients by utilizing the area under the receiver operating characteristic (ROC) curve (AUC) analysis. METHODS We searched Ovid MEDLINE, EMBASE, and the Cochrane Library for eligible articles through January 2021. Studies were included based on the following criteria: (1) Study nature was observational or conference abstract; (2) Study populations involved patients with non-transplant CKD at any CKD stage severity; and (3) Predictive factors for mortality were presented with AUC analysis and its associated 95% confidence interval (CI). AUC of 0.70-0.79 is considered acceptable, 0.80-0.89 is considered excellent, and more than 0.90 is considered outstanding. RESULTS Of 1759 citations, a total of 18 studies (n = 14579) were included in this systematic review. Eight hundred thirty two patients had non-dialysis CKD, and 13747 patients had dialysis-dependent CKD (2160 patients on hemodialysis, 370 patients on peritoneal dialysis, and 11217 patients on non-differentiated dialysis modality). Of 24 mortality predictive factors, none were deemed outstanding for mortality prediction. A total of seven predictive factors [N-terminal pro-brain natriuretic peptide (NT-proBNP), BNP, soluble urokinase plasminogen activator receptor (suPAR), augmentation index, left atrial reservoir strain, C-reactive protein, and systolic pulmonary artery pressure] were identified as excellent. Seventeen predictive factors were in the acceptable range, which we classified into the following subgroups: predictors for the non-dialysis population, echocardiographic factors, comorbidities, and miscellaneous. CONCLUSION Several factors were found to predict mortality in CKD patients. Echocardiography is an important tool for mortality prognostication in CKD patients by evaluating left atrial reservoir strain, systolic pulmonary artery pressure, diastolic function, and left ventricular mass index.
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Affiliation(s)
- Panupong Hansrivijit
- Department of Internal Medicine, UPMC Pinnacle, Harrisburg, PA 17104, United States
| | - Yi-Ju Chen
- Department of Internal Medicine, UPMC Pinnacle, Harrisburg, PA 17104, United States
| | - Kriti Lnu
- Department of Internal Medicine, UPMC Pinnacle, Harrisburg, PA 17104, United States
| | - Angkawipa Trongtorsak
- Department of Internal Medicine, Amita Health Saint Francis Hospital, Evanston, IL 60202, United States
| | - Max M Puthenpura
- Department of Medicine, Drexel University College of Medicine, Philadelphia, PA 19129, United States
| | - Charat Thongprayoon
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, United States
| | - Tarun Bathini
- Department of Internal Medicine, University of Arizona, Tucson, AZ 85721, United States
| | - Michael A Mao
- Division of Nephrology and Hypertension, Mayo Clinic, Jacksonville, FL 32224, United States
| | - Wisit Cheungpasitporn
- Division of Nephrology and Hypertension, Department of Medicine, Mayo Clinic, Rochester, MN 55905, United States
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16
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Yang HW, Garaulet M, Li P, Bandin C, Lin C, Lo MT, Hu K. Daily Rhythm of Fractal Cardiac Dynamics Links to Weight Loss Resistance: Interaction with CLOCK 3111T/C Genetic Variant. Nutrients 2021; 13:nu13072463. [PMID: 34371977 PMCID: PMC8308644 DOI: 10.3390/nu13072463] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/09/2021] [Accepted: 07/13/2021] [Indexed: 12/31/2022] Open
Abstract
The effectiveness of weight loss treatment displays dramatic inter-individual variabilities, even with well-controlled energy intake/expenditure. This study aimed to determine the association between daily rhythms of cardiac autonomic control and weight loss efficiency and to explore the potential relevance to weight loss resistance in humans carrying the genetic variant C at CLOCK 3111T/C. A total of 39 overweight/obese Caucasian women (20 CLOCK 3111C carriers and 19 non-carriers) completed a behaviour–dietary obesity treatment of ~20 weeks, during which body weight was assessed weekly. Ambulatory electrocardiographic data were continuously collected for up to 3.5 days and used to quantify the daily rhythm of fractal cardiac dynamics (FCD), a non-linear measure of autonomic function. FCD showed a 24 h rhythm (p < 0.001). Independent of energy intake and physical activity level, faster weight loss was observed in individuals with the phase (peak) of the rhythm between ~2–8 p.m. and with a larger amplitude. Interestingly, the phase effect was significant only in C carriers (p = 0.008), while the amplitude effect was only significant in TT carriers (p < 0.0001). The daily rhythm of FCD and CLOCK 3111T/C genotype is linked to weight loss response interactively, suggesting complex interactions between the genetics of the circadian clock, the daily rhythm of autonomic control, and energy balance control.
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Affiliation(s)
- Hui-Wen Yang
- Graduate Institute of Communication Engineering, National Taiwan University, Taipei 10617, Taiwan;
- Institute of Translational and Interdisciplinary Medicine, Department of Biomedical Sciences and Engineering, National Central University, Taoyuan 320317, Taiwan;
- Division of Sleep and Circadian Disorders, Department of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA 02115, USA;
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Marta Garaulet
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
- Department of Physiology, University of Murcia, IMIB, 30071 Murcia, Spain;
- Correspondence: (M.G.); (M.-T.L.); (K.H.)
| | - Peng Li
- Division of Sleep and Circadian Disorders, Department of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA 02115, USA;
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Cristina Bandin
- Department of Physiology, University of Murcia, IMIB, 30071 Murcia, Spain;
| | - Chen Lin
- Institute of Translational and Interdisciplinary Medicine, Department of Biomedical Sciences and Engineering, National Central University, Taoyuan 320317, Taiwan;
| | - Men-Tzung Lo
- Institute of Translational and Interdisciplinary Medicine, Department of Biomedical Sciences and Engineering, National Central University, Taoyuan 320317, Taiwan;
- Correspondence: (M.G.); (M.-T.L.); (K.H.)
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Department of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA 02115, USA;
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
- Correspondence: (M.G.); (M.-T.L.); (K.H.)
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17
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Laukkanen JA, Kurl S, Khan H, Kunutsor SK. Percentage of age-predicted cardiorespiratory fitness and risk of sudden cardiac death: A prospective cohort study. Heart Rhythm 2021; 18:1171-1177. [PMID: 33689907 DOI: 10.1016/j.hrthm.2021.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 02/26/2021] [Accepted: 03/02/2021] [Indexed: 01/08/2023]
Abstract
BACKGROUND The inverse associations between cardiorespiratory fitness (CRF) and vascular outcomes have been established. However, there has been no prospective evaluation of the relationship between percentage of age-predicted cardiorespiratory fitness (%age-predicted CRF) and risk of sudden cardiac death (SCD). OBJECTIVE The purpose of this study was to assess the association of %age-predicted CRF with SCD risk in a long-term prospective cohort study. METHODS CRF was assessed using the gold standard respiratory gas exchange analyzer in 2276 men who underwent cardiopulmonary exercise testing. The age-predicted CRF estimated from a regression equation for age was converted to %age-predicted CRF using (Achieved CRF/Age-predicted CRF) × 100. Hazard ratios (HRs) [95% confidence intervals (CIs)] were calculated for SCD. RESULTS During median follow-up of 28.2 years, 260 SCDs occurred. There was a dose-response relationship between age-predicted CRF and SCD. A 1-SD increase in %age-predicted CRF was associated with a decreased risk of SCD in analysis adjusted for established risk factors (HR 0.60; 95% CI 0.53-0.70), which remained consistent on further adjustment for several potential confounders, including alcohol consumption, physical activity, socioeconomic status, and systemic inflammation (HR 0.73; 95% CI 0.62-0.85). The corresponding adjusted HRs were 0.34 (0.23-0.50) and 0.52 (0.34-0.79), respectively, when comparing extreme quartiles of %age-predicted CRF levels. HRs for the associations of absolute CRF levels with SCD risk in the same participants were similar. CONCLUSION Percentage of age-predicted CRF is continuously, strongly, and independently associated with risk of SCD and is comparable to absolute CRF as a risk indicator for SCD.
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Affiliation(s)
- Jari A Laukkanen
- Institute of Clinical Medicine, Department of Medicine, University of Eastern Finland, Kuopio, Finland; Central Finland Health Care District, Department of Medicine, Jyväskylä, Finland; Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland.
| | - Sudhir Kurl
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Hassan Khan
- Section of Cardiac Electrophysiology, The Leon H. Charney Division of Cardiology, NYU Langone Health, NYU Robert I. Grossman School of Medicine, New York, USA
| | - Setor K Kunutsor
- National Institute for Health Research Bristol Biomedical Research Centre, University Hospitals Bristol and Weston NHS Foundation Trust and the University of Bristol, Bristol, United Kingdom; Translational Health Sciences, Bristol Medical School, University of Bristol, Learning & Research, Southmead Hospital, Bristol, United Kingdom
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18
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Murugappan M, Murugesan L, Jerritta S, Adeli H. Sudden Cardiac Arrest (SCA) Prediction Using ECG Morphological Features. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2021. [DOI: 10.1007/s13369-020-04765-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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19
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Fractal Dynamics in the RR Interval of Craniopharyngioma and Adrenal Tumor in Adolescence. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1338:183-191. [DOI: 10.1007/978-3-030-78775-2_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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Qin H, Steenbergen N, Glos M, Wessel N, Kraemer JF, Vaquerizo-Villar F, Penzel T. The Different Facets of Heart Rate Variability in Obstructive Sleep Apnea. Front Psychiatry 2021; 12:642333. [PMID: 34366907 PMCID: PMC8339263 DOI: 10.3389/fpsyt.2021.642333] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 06/14/2021] [Indexed: 12/15/2022] Open
Abstract
Obstructive sleep apnea (OSA), a heterogeneous and multifactorial sleep related breathing disorder with high prevalence, is a recognized risk factor for cardiovascular morbidity and mortality. Autonomic dysfunction leads to adverse cardiovascular outcomes in diverse pathways. Heart rate is a complex physiological process involving neurovisceral networks and relative regulatory mechanisms such as thermoregulation, renin-angiotensin-aldosterone mechanisms, and metabolic mechanisms. Heart rate variability (HRV) is considered as a reliable and non-invasive measure of autonomic modulation response and adaptation to endogenous and exogenous stimuli. HRV measures may add a new dimension to help understand the interplay between cardiac and nervous system involvement in OSA. The aim of this review is to introduce the various applications of HRV in different aspects of OSA to examine the impaired neuro-cardiac modulation. More specifically, the topics covered include: HRV time windows, sleep staging, arousal, sleepiness, hypoxia, mental illness, and mortality and morbidity. All of these aspects show pathways in the clinical implementation of HRV to screen, diagnose, classify, and predict patients as a reasonable and more convenient alternative to current measures.
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Affiliation(s)
- Hua Qin
- Interdisciplinary Center of Sleep Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Martin Glos
- Interdisciplinary Center of Sleep Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Niels Wessel
- Department of Physics, Humboldt Universität zu Berlin, Berlin, Germany
| | - Jan F Kraemer
- Department of Physics, Humboldt Universität zu Berlin, Berlin, Germany
| | - Fernando Vaquerizo-Villar
- Biomedical Engineering Group, Universidad de Valladolid, Valladolid, Spain.,Centro de Investigación Biomédica en Red-Bioingeniería, Biomateriales y Nanomedicina, Valladolid, Spain
| | - Thomas Penzel
- Interdisciplinary Center of Sleep Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany.,Saratov State University, Russian Federation, Saratov, Russia
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21
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Mujib Kamal S, Babini MH, Krejcar O, Namazi H. Complexity-Based Decoding of the Coupling Among Heart Rate Variability (HRV) and Walking Path. Front Physiol 2020; 11:602027. [PMID: 33324242 PMCID: PMC7723866 DOI: 10.3389/fphys.2020.602027] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/14/2020] [Indexed: 01/04/2023] Open
Abstract
Walking is an everyday activity in our daily life. Because walking affects heart rate variability, in this research, for the first time, we analyzed the coupling among the alterations of the complexity of walking paths and heart rate. We benefited from the fractal theory and sample entropy to evaluate the influence of the complexity of paths on the complexity of heart rate variability (HRV) during walking. We calculated the fractal exponent and sample entropy of the R-R time series for nine participants who walked on four paths with various complexities. The findings showed a strong coupling among the alterations of fractal dimension (an indicator of complexity) of HRV and the walking paths. Besides, the result of the analysis of sample entropy also verified the obtained results from the fractal analysis. In further studies, we can analyze the coupling among the alterations of the complexities of other physiological signals and walking paths.
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Affiliation(s)
| | | | - Ondrej Krejcar
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Králové, Hradec Králové, Czechia
| | - Hamidreza Namazi
- School of Engineering, Monash University Malaysia, Selangor, Malaysia.,Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Králové, Hradec Králové, Czechia
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Nardelli M, Citi L, Barbieri R, Valenza G. Intrinsic Complexity of Sympathetic and Parasympathetic Dynamics from HRV series: a Preliminary Study on Postural Changes. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:2577-2580. [PMID: 33018533 DOI: 10.1109/embc44109.2020.9175587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The analysis of complex heartbeat dynamics has been widely used to characterize heartbeat autonomic control in healthy and pathological conditions. However, underlying physiological correlates of complexity measurements from heart rate variability (HRV) series have not been identified yet. To this extent, we investigated intrinsic irregularity and complexity of cardiac sympathetic and vagal activity time series during postural changes. We exploited our recently proposed HRV-based, time-varying Sympathetic and Parasympathetic Activity Indices (SAI and PAI) and performed Sample Entropy, Fuzzy Entropy, and Distribution Entropy calculations on publicly-available heartbeat series gathered from 10 healthy subjects undergoing resting state and passive slow tilt sessions. Results show significantly higher entropy values during the upright position than resting state in both SAI and PAI series. We conclude that an increase in HRV complexity resulting from postural changes may derive from sympathetic and vagal activities with higher complex dynamics.
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Porta A, Bari V, Cairo B, De Maria B, Vaini E, Barbic F, Furlan R. Comparison of symbolization strategies for complexity assessment of spontaneous variability in individuals with signs of cardiovascular control impairment. Biomed Signal Process Control 2020. [DOI: 10.1016/j.bspc.2020.102128] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Janczarek I, Kędzierski W, Wilk I, Wnuk–Pawlak E, Rakowska A. Comparison of daily heart rate variability in old and young horses: A preliminary study. J Vet Behav 2020. [DOI: 10.1016/j.jveb.2020.05.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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25
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Wee BYH, Lee JH, Mok YH, Chong SL. A narrative review of heart rate and variability in sepsis. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:768. [PMID: 32647693 PMCID: PMC7333166 DOI: 10.21037/atm-20-148] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Clinicians face challenges in the timely diagnosis and management of pediatric sepsis. Pediatric heart rate has been incorporated into early warning systems and studied as a predictor for critical illness. We aim to review: (I) the role of heart rate in pediatric warning systems and (II) the role of heart rate variability (HRV) in adult and neonatal sepsis, with a focus on its potential applications in pediatrics. We conducted a literature search for papers published up to December 2019 on the utility of heart rate and HRV analysis in the diagnosis and management of sepsis, using four medical databases: PubMed, Google Scholar, EMBASE and Web of Science. This review demonstrates that the clinical utility of pediatric heart rate in predicting clinical deterioration is limited by the lack of consensus among warning systems, consensus-based guidelines, and evidence-based studies as to what constitutes abnormal heart rate in the pediatric age group. Current studies demonstrate that abnormal heart rate itself does not adequately discriminate children with sepsis from those without. HRV analysis provides a quick and non-invasive method of assessment and can provide more information than traditional heart rate. HRV analysis has the potential to add value in identification and prognostication of adult and neonatal sepsis. With further studies to explore its role, HRV analysis has the potential to add to current tools in the diagnosis and prognosis of pediatric sepsis.
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Affiliation(s)
- Benjamin Yi Hao Wee
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Jan Hau Lee
- Children's Intensive Care Unit, KK Women's and Children's Hospital, Singapore, Singapore.,Duke-NUS Medical School, Singapore, Singapore
| | - Yee Hui Mok
- Children's Intensive Care Unit, KK Women's and Children's Hospital, Singapore, Singapore.,Duke-NUS Medical School, Singapore, Singapore
| | - Shu-Ling Chong
- Duke-NUS Medical School, Singapore, Singapore.,Department of Emergency Medicine, KK Women's and Children's Hospital, Singapore, Singapore
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26
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Costalat G, Godin B, Balmain BN, Moreau C, Brotherton E, Billaut F, Lemaitre F. Autonomic regulation of the heart and arrhythmogenesis in trained breath-hold divers. Eur J Sport Sci 2020; 21:439-449. [PMID: 32223533 DOI: 10.1080/17461391.2020.1749313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AbstractBreath-hold divers are known to develop cardiac autonomic changes and brady-arrthymias during prolonged breath-holding (BH). The effects of BH-induced hypoxemia were investigated upon both cardiac autonomic status and arrhythmogenesis by comparing breath-hold divers (BHDs) to non-divers (NDs). Eighteen participants (9 BHDs, 9 NDs) performed a maximal voluntary BH with face immersion. BHDs were asked to perform an additional BH at water surface to increase the degree of hypoxemia. Beat-to-beat changes in heart rate (HR), short-term fractal scaling exponent (DFAα1), the number of arrhythmic events [premature ventricular contractions (PVCs), premature atrial contractions (PACs)] and peripheral oxygen saturation (SpO2) were recorded during and immediately following BH. The corrected QT-intervals (QTc) were analyzed pre- and post-acute BH. A regression-based model was used to split BH into a normoxic (NX) and a hypoxemic phase (HX). During the HX phase of BH, BHDs showed a progressive decrease in DFAα1 during BH with face immersion (p < 0.01) and BH with whole-body immersion (p < 0.01) whereas NDs did not (p > 0.05). In addition, BHDs had more arrhythmic events during the HX of BH with whole-body immersion when compared to the corresponding NX phase (5.9 ± 6.7 vs 0.4 ± 1.3; p < 0.05; respectively). The number of PVCs was negatively correlated with SpO2 during BH with whole-body immersion (r = -0.72; p < 0.05). The hypoxemic stage of voluntary BH is concomitant with significant cardiac autonomic changes toward a synergistic sympathetic and parasympathetic stimulation. Co-activation led ultimately to increased bradycardic response and cardiac electrophysiological disturbances.
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Affiliation(s)
- Guillaume Costalat
- Faculty of Sport Sciences, APERE laboratory, EA 3300, University of Picardie Jules Verne, France
| | | | - Bryce N Balmain
- School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia
| | - Clara Moreau
- CHU Sainte Justine - Brain and Child Development, University of Montreal, Canada
| | - Emily Brotherton
- School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia
| | - Francois Billaut
- Département de kinésiologie, Faculté de Médecine, Université Laval, Québec, Canada
| | - Frederic Lemaitre
- Faculty of Sport Sciences, CETAPS laboratory, EA 3832, Normandy University, France
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27
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Li P, Yu L, Yang J, Lo MT, Hu C, Buchman AS, Bennett DA, Hu K. Interaction between the progression of Alzheimer's disease and fractal degradation. Neurobiol Aging 2019; 83:21-30. [PMID: 31585364 PMCID: PMC6858962 DOI: 10.1016/j.neurobiolaging.2019.08.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 08/22/2019] [Accepted: 08/24/2019] [Indexed: 01/08/2023]
Abstract
Many outputs from healthy neurophysiological systems including motor activity display nonrandom fluctuations with fractal scaling behavior as characterized by similar temporal fluctuation patterns across a range of time scales. Degraded fractal regulation predicts adverse consequences including Alzheimer's dementia. We examined longitudinal changes in the scaling behavior of motor activity fluctuations during the progression of Alzheimer's disease (AD) in 1068 participants in the Rush Memory and Aging Project. Motor activity of up to 10 days was recorded annually for up to 13 years. Cognitive assessments and clinical diagnoses were administered annually in the same participants. We found that fractal regulation gradually degraded over time (p < 0.0001) even during the stage with no cognitive impairment. The degradation rate was more than doubled after the diagnosis of mild cognitive impairment and more than doubled further after the diagnosis of Alzheimer's dementia (p's ≤ 0.0005). Besides, the longitudinal degradation of fractal regulation significantly correlated with the decline in cognitive performance throughout the progression from no cognitive impairment to mild cognitive impairment, and to AD (p < 0.001). All effects remained the same in subsequent sensitivity analyses that included only 255 decedents with autopsy-confirmed Alzheimer's pathology. These results indicate that the progression of AD accelerates fractal degradation and that fractal degradation may be an integral part of the process of AD.
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Affiliation(s)
- Peng Li
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Jingyun Yang
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Men-Tzung Lo
- Institute of Translational and Interdisciplinary Medicine and Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Chelsea Hu
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
| | - Aron S Buchman
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
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Torre K, Vergotte G, Viel É, Perrey S, Dupeyron A. Fractal properties in sensorimotor variability unveil internal adaptations of the organism before symptomatic functional decline. Sci Rep 2019; 9:15736. [PMID: 31673034 PMCID: PMC6823488 DOI: 10.1038/s41598-019-52091-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 09/28/2019] [Indexed: 01/20/2023] Open
Abstract
If health can be defined as adaptability, then measures of adaptability are crucial. Convergent findings across clinical areas established the notion that fractal properties in bio-behavioural variability characterize the healthy condition of the organism, and its adaptive capacities in general. However, ambiguities remain as to the significance of fractal properties: the literature mainly discriminated between healthy vs. pathological states, thereby loosing perspective on the progression in between, and overlooking the distinction between adaptability and effective adaptations of the organism. Here, we design an experimental tapping paradigm involving gradual feedback deprivation in groups of healthy subjects and one deafferented man as a pathological-limit case. We show that distinct types of fractal properties in sensorimotor behaviour characterize, on the one hand impaired functional ability, and on the other hand internal adaptations for maintaining performance despite the imposed constraints. Findings may prove promising for early detection of internal adaptations preceding symptomatic functional decline.
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Affiliation(s)
| | | | | | | | - Arnaud Dupeyron
- EuroMov, Univ. Montpellier, Montpellier, France.,CHU Carémeau, Nîmes, France
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Korolj A, Wu HT, Radisic M. A healthy dose of chaos: Using fractal frameworks for engineering higher-fidelity biomedical systems. Biomaterials 2019; 219:119363. [PMID: 31376747 PMCID: PMC6759375 DOI: 10.1016/j.biomaterials.2019.119363] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 07/09/2019] [Accepted: 07/14/2019] [Indexed: 12/18/2022]
Abstract
Optimal levels of chaos and fractality are distinctly associated with physiological health and function in natural systems. Chaos is a type of nonlinear dynamics that tends to exhibit seemingly random structures, whereas fractality is a measure of the extent of organization underlying such structures. Growing bodies of work are demonstrating both the importance of chaotic dynamics for proper function of natural systems, as well as the suitability of fractal mathematics for characterizing these systems. Here, we review how measures of fractality that quantify the dose of chaos may reflect the state of health across various biological systems, including: brain, skeletal muscle, eyes and vision, lungs, kidneys, tumours, cell regulation, skin and wound repair, bone, vasculature, and the heart. We compare how reports of either too little or too much chaos and fractal complexity can be damaging to normal biological function, and suggest that aiming for the healthy dose of chaos may be an effective strategy for various biomedical applications. We also discuss rising examples of the implementation of fractal theory in designing novel materials, biomedical devices, diagnostics, and clinical therapies. Finally, we explain important mathematical concepts of fractals and chaos, such as fractal dimension, criticality, bifurcation, and iteration, and how they are related to biology. Overall, we promote the effectiveness of fractals in characterizing natural systems, and suggest moving towards using fractal frameworks as a basis for the research and development of better tools for the future of biomedical engineering.
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Affiliation(s)
- Anastasia Korolj
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Canada
| | - Hau-Tieng Wu
- Department of Statistical Science, Duke University, Durham, NC, USA; Department of Mathematics, Duke University, Durham, NC, USA; Mathematics Division, National Center for Theoretical Sciences, Taipei, Taiwan
| | - Milica Radisic
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Canada; Toronto General Research Institute, University Health Network, Toronto, Canada; The Heart and Stroke/Richard Lewar Center of Excellence, Toronto, Canada.
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30
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Shi B, Wang L, Yan C, Chen D, Liu M, Li P. Nonlinear heart rate variability biomarkers for gastric cancer severity: A pilot study. Sci Rep 2019; 9:13833. [PMID: 31554856 PMCID: PMC6761171 DOI: 10.1038/s41598-019-50358-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 09/11/2019] [Indexed: 12/24/2022] Open
Abstract
Identifying prognostic factors by affordable tools is crucial for guiding gastric cancer (GC) treatments especially at earlier stages for timing interventions. The autonomic function that is clinically assessed by heart rate variability (HRV) is involved in tumorigenesis. This pilot study was aimed to examine whether nonlinear indices of HRV can be biomarkers of GC severity. Sixty-one newly-diagnosed GC patients were enrolled. Presurgical serum fibrinogen (FIB), carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA199) were examined. Resting electrocardiogram (ECG) of 5-min was collected prior to surgical treatments to enable the HRV analysis. Twelve nonlinear HRV indices covering the irregularity, complexity, asymmetry, and temporal correlation of heartbeat fluctuations were obtained. Increased short-range temporal correlations, decreased asymmetry, and increased irregularity of heartbeat fluctuations were associated with higher FIB level. Increased irregularity and decreased complexity were also associated with higher CEA level. These associations were independent of age, sex, BMI, alcohol consumption, history of diabetes, left ventricular ejection fraction, and anemia. The results support the hypothesis that perturbations in nonlinear dynamical patterns of HRV predict increased GC severity. Replication in larger samples as well as the examination of longitudinal associations of HRV nonlinear features with cancer prognosis/survival are warranted.
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Affiliation(s)
- Bo Shi
- School of Medical Imaging, Bengbu Medical College, Bengbu, Anhui, 233030, China
| | - Lili Wang
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233004, China
| | - Chang Yan
- School of Control Science and Engineering, Shandong University, Jinan, Shandong, 250061, China
| | - Deli Chen
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233004, China
| | - Mulin Liu
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233004, China
| | - Peng Li
- School of Control Science and Engineering, Shandong University, Jinan, Shandong, 250061, China.
- Division of Sleep and Circadian Disorders, Brigham & Women's Hospital, Harvard Medical School, Boston, 02115, MA, USA.
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Kališnik JM, Avbelj V, Vratanar J, Santarpino G, Geršak B, Fischlein T, Trobec R, Žibert J. Cardiac autonomic regulation and PR interval determination for enhanced atrial fibrillation risk prediction after cardiac surgery. Int J Cardiol 2019; 289:24-29. [PMID: 31072633 DOI: 10.1016/j.ijcard.2019.04.070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/25/2019] [Accepted: 04/23/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Changes in cardiac autonomic regulation and P-wave characteristics are associated with the occurrence of atrial fibrillation. The purpose of this study was to evaluate whether combined preoperative non-invasive determination of cardiac autonomic regulation and PR interval allows for the identification of patients at risk of new-onset atrial fibrillation after cardiac surgery. METHODS RR, PR and QT intervals, and linear and non-linear heart rate variability parameters from 20 min high-resolution electrocardiographic recordings were determined one day before surgery in 150 patients on chronic beta blockers undergoing elective coronary artery bypass grafting, aortic valve replacement, or both, electively. RESULTS Thirty-one patients (21%) developed postoperative atrial fibrillation. In the atrial fibrillation group, more arterial hypertension, a greater age, a higher EuroSCORE II, a higher heart rate variability index (pNN50: 9 ± 20 vs. 4 ± 10, p = 0.050), a short PR interval (156 ± 23 vs. 173 ± 31 ms; p = 0.011), and a reduced short-term scaling exponent of the detrended fluctuation analysis (DFA1, 0.96 ± 0.36 vs. 1.11 ± 0.30 ms; p = 0.032) were found compared to the sinus rhythm group. Logistic regression modeling confirmed PR interval, DFA1 and age as the strongest preoperative predictors of postoperative atrial fibrillation (area under the receiver operating characteristic curve = 0.804). CONCLUSIONS Patients developing atrial fibrillation after cardiac surgery presented with severe cardiac autonomic derangement and a short PR interval preoperatively. The observed state characterizes both altered heart rate regulation and arrhythmic substrate and is strongly related to an increased risk of postoperative atrial fibrillation.
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Affiliation(s)
- Jurij M Kališnik
- Department of Cardiovascular Surgery, University Medical Center, Ljubljana, Slovenia; Department of Cardiac Surgery, Cardiovascular Center, Klinikum Nuernberg-Paracelsus Medical University, Nuremberg, Germany.
| | - Viktor Avbelj
- Department of Communication Systems, Jozef Stefan Institute, Ljubljana, Slovenia.
| | - Jon Vratanar
- Department of Cardiovascular Surgery, University Medical Center, Ljubljana, Slovenia
| | - Giuseppe Santarpino
- Department of Cardiac Surgery, Cardiovascular Center, Klinikum Nuernberg-Paracelsus Medical University, Nuremberg, Germany; Department of Cardiac Surgery, Città di Lecce Hospital, GVM Care & Research, Lecce, Italy
| | - Borut Geršak
- Department of Cardiovascular Surgery, University Medical Center, Ljubljana, Slovenia
| | - Theodor Fischlein
- Department of Cardiac Surgery, Cardiovascular Center, Klinikum Nuernberg-Paracelsus Medical University, Nuremberg, Germany.
| | - Roman Trobec
- Department of Communication Systems, Jozef Stefan Institute, Ljubljana, Slovenia.
| | - Janez Žibert
- Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia.
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32
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Kolte A, Olsen L, Christiansen O, Schmidt L, Nielsen H. Pregnancy outcomes after recurrent pregnancy loss: a longitudinal cohort study on stress and depression. Reprod Biomed Online 2019; 38:599-605. [DOI: 10.1016/j.rbmo.2018.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 09/08/2018] [Accepted: 12/10/2018] [Indexed: 12/30/2022]
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Alterations in heart rate variability in patients with peripheral arterial disease requiring surgical revascularization have limited association with postoperative major adverse cardiovascular and cerebrovascular events. PLoS One 2018; 13:e0203519. [PMID: 30212552 PMCID: PMC6136721 DOI: 10.1371/journal.pone.0203519] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 08/22/2018] [Indexed: 11/29/2022] Open
Abstract
Objective Obstructive sleep apnea (OSA) is common in peripheral arterial disease (PAD) and associates with high mortality after surgery. Since abnormal heart rate variability (HRV) is predictive of postoperative complications, we investigated the relations of HRV with PAD, OSA and major adverse cardiovascular and cerebrovascular events (MACCE). Materials and methods Seventy-five patients (67±9 years) scheduled for sub-inguinal revascularization and 15 controls (63±6 years) underwent polysomnography and HRV analyses. OSA with an apnea-hypopnea index (AHI) ≥20/hour was considered significant. HRV was measured during wakefulness, S2, S3-4 and rapid eye movement (REM) sleep with time and frequency domain methods including beat-to-beat variability, low frequency (LF) and high frequency (HF) power, and detrended fluctuation analysis (DFA). MACCE was defined as cardiac death, myocardial infarction, coronary revascularization, hospitalized angina pectoris and stroke. Results Thirty-six patients (48%) had AHI≥20/hour. During follow-up (median 52 months), 22 patients (29%) suffered a MACCE. Compared to controls, fractal correlation of HRV (scaling exponent alpha 1 measured with DFA) was weaker during S2 and evening wakefulness in all subgroups (+/-AHI≥20/hour, +/-MACCE) but only in patients with AHI≥20/hour during morning wakefulness. The LF/HF ratio was lower in all subgroups during S2 but only in patients with AHI ≥20/hour during evening or morning wake. In the covariance analysis adjusted for age, body mass index, coronary artery disease and PAD duration, the alpha 1 during morning wakefulness remained significantly lower in patients with AHI≥20/hour than in those without (1.12 vs. 1.45; p = 0.03). Decreased HF during REM (p = 0.04) and S3-4 sleep (p = 0.03) were predictive of MACCE. In analyses with all sleep stages combined, mean heart rate as well as very low frequency, LF, HF and total power were associated with OSA of mild-to-moderate severity (AHI 10-20/hour). Conclusions HRV is altered in patients with PAD. These alterations have a limited association with OSA and MACCE.
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Carvalho LP, Di Thommazo-Luporini L, Mendes RG, Cabiddu R, Ricci PA, Basso-Vanelli RP, Oliveira-Junior MC, Vieira RP, Bonjorno-Junior JC, Oliveira CR, Luporini RL, Borghi-Silva A. Metabolic syndrome impact on cardiac autonomic modulation and exercise capacity in obese adults. Auton Neurosci 2018; 213:43-50. [PMID: 30005739 DOI: 10.1016/j.autneu.2018.05.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/18/2018] [Accepted: 05/17/2018] [Indexed: 10/16/2022]
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Šapina M, Kośmider M, Kramarić K, Garcin M, Adelson PD, Pirić M, Milas K, Brdarić D. Asymmetric detrended fluctuation analysis in neonatal stress. Physiol Meas 2018; 39:085006. [PMID: 30019692 DOI: 10.1088/1361-6579/aad425] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To detect stress in newborns by observing heart rate (HR) variability utilizing an asymmetric detrended fluctuation analysis (ADFA), we sought to determine the fractal structure of the series of inter-beat intervals, so as to distinguish the periods of acceleration of the HR from decelerations. Thus, two scaling exponents, α + and α -, representing decelerations and accelerations respectively, are obtained. APPROACH Forty healthy term newborns were included in this study, undergoing two different types of stress stimuli: routine heel lance blood sampling for metabolic screening purposes, and its simulation by applying dull pressure on the heel. MAIN RESULTS It appears that when newborns face stress, the scaling exponent related to accelerations significantly increases and becomes higher than the deceleration scaling exponent. To test the diagnostic properties of the scaling exponents, an ROC curve analysis was applied; α - showed good diagnostic performance with an AUC between 0.626 and 0.826, depending on the length of the time series. The joint use of α + and α - further increased the diagnostic performance, in particular for shorter series of RR intervals, with an AUC between 0.691 and 0.833. SIGNIFICANCE ADFA, particularly of the acceleration scaling exponent, may be a useful clinical diagnostic tool for monitoring neonatal stress.
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Affiliation(s)
- Matej Šapina
- University hospital Osijek, Pediatric Clinic, J. Huttlera 4, 31000 Osijek, Croatia. Medical faculty Osijek, Osijek, Cara Hadrijana 10E, 31000 Osijek, Croatia. Faculty of Dental medicine and Health, Crkvena 21, 31000 Osijek, Croatia
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Vergotte G, Perrey S, Muthuraman M, Janaqi S, Torre K. Concurrent Changes of Brain Functional Connectivity and Motor Variability When Adapting to Task Constraints. Front Physiol 2018; 9:909. [PMID: 30042697 PMCID: PMC6048415 DOI: 10.3389/fphys.2018.00909] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/21/2018] [Indexed: 01/08/2023] Open
Abstract
In behavioral neuroscience, the adaptability of humans facing different constraints has been addressed on one side at the brain level, where a variety of functional networks dynamically support the same performance, and on the other side at the behavioral level, where fractal properties in sensorimotor variables have been considered as a hallmark of adaptability. To bridge the gap between the two levels of observation, we have jointly investigated the changes of network connectivity in the sensorimotor cortex assessed by modularity analysis and the properties of motor variability assessed by multifractal analysis during a prolonged tapping task. Four groups of participants had to produce the same tapping performance while being deprived from 0, 1, 2, or 3 sensory feedbacks simultaneously (auditory and/or visual and/or tactile). Whereas tapping performance was not statistically different across groups, the number of brain networks involved and the degree of multifractality of the inter-tap interval series were significantly correlated, increasing as a function of feedback deprivation. Our findings provide first evidence that concomitant changes in brain modularity and multifractal properties characterize adaptations underlying unchanged performance. We discuss implications of our findings with respect to the degeneracy properties of complex systems, and the entanglement of adaptability and effective adaptation.
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Affiliation(s)
| | | | - Muthuraman Muthuraman
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Focus Program Translational Neuroscience (FTN), Department of Neurology, Johannes Gutenberg University, Mainz, Germany
| | - Stefan Janaqi
- LGI2P, Institut Mines Télécom-Ecole des Mines d'Alès, Alès, France
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Sen J, McGill D. Fractal analysis of heart rate variability as a predictor of mortality: A systematic review and meta-analysis. CHAOS (WOODBURY, N.Y.) 2018; 28:072101. [PMID: 30070502 DOI: 10.1063/1.5038818] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/10/2018] [Indexed: 05/21/2023]
Abstract
Previous studies have suggested benefits of applying fractal analysis to intervals between R waves in electrocardiography as an additional prognostic marker. The aim of this study was to investigate whether fractal analysis can provide an independent predictor of cardiac mortality or all-cause mortality. Prognostic cohort studies reporting fractal heart rate variability results from 24-h Holter monitor recordings were selected for comparison. Populations were subdivided into four groups-post-myocardial infarction, left ventricular dysfunction, other cardiac, and non-cardiac patients-and analysed using ANOVA, Forest plots (using pooled mean difference), and Funnel plots. The most significant mean differences were recorded in short-term fractal self-similarity (α1) (-0.17, 95% CI [-0.21, -0.13], p < 0.00001) and the traditional measure called standard deviation of NN intervals (SDNN) (-13.31, 95% CI [-18.89, -7.73], p < 0.00001) between the deceased and survivor groups. Fractal measures of long-term fractal self-similarity (α2), 1/f scaling (β), and traditional heart rate variability measures of high frequency to low frequency ratio show promise. This review indicated that fractal measure α1 and traditional measure SDNN could be potential predictors of mortality, but require further assessment to determine appropriate thresholds for clinical significance and additional targeted prognostic studies to properly define their applicability as prognostic markers. Therefore, clinicians should interpret fractal and traditional measures with caution since such measures have yet to be fully described as biomarkers for clinical application.
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Affiliation(s)
- Jonathan Sen
- Cardiology Research Unit, University Hospital Geelong, Barwon Health, PO Box 281, Geelong, Victoria 3220, Australia
| | - Darryl McGill
- Cardiology Department, Canberra Hospital, Yamba Drive, Garran, Australian Capital Territory 2605, Australia
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38
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Kloter E, Barrueto K, Klein SD, Scholkmann F, Wolf U. Heart Rate Variability as a Prognostic Factor for Cancer Survival - A Systematic Review. Front Physiol 2018; 9:623. [PMID: 29896113 PMCID: PMC5986915 DOI: 10.3389/fphys.2018.00623] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/08/2018] [Indexed: 12/11/2022] Open
Abstract
An increasing cancer incidence affecting any age and social class is putting serious strain on populations and health care systems around the world. This systematic literature search aims (i) to examine the correlation of heart rate variability (HRV) and cancer patients' prognosis, (ii) to examine the relationship of HRV and clinicopathological features, and (iii) to compare HRV between different patient groups, and between patient and control groups. We conducted a systematic literature review following the PRISMA Statement. We searched the PubMed and EMBASE databases for publications released by December 2017. The search terms were: "cancer" AND "heart rate variability" AND "human" NOT "animal" NOT "review." A total of 19 studies were finally included in this review. Most publications were high-quality observational studies. The studies showed that higher HRV correlated positively with patients' progression of disease and outcome. Thus, we conclude that individuals with higher HRV and advanced coping mechanisms seem to have a better prognosis in cancer progression. HRV appears to be a useful aspect to access the general health status of cancer patients.
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Affiliation(s)
- Evelyne Kloter
- Institute of Complementary Medicine, University of Bern, Bern, Switzerland
| | - Katja Barrueto
- Institute of Complementary Medicine, University of Bern, Bern, Switzerland
| | - Sabine D Klein
- Institute of Complementary Medicine, University of Bern, Bern, Switzerland
| | - Felix Scholkmann
- Institute of Complementary Medicine, University of Bern, Bern, Switzerland
| | - Ursula Wolf
- Institute of Complementary Medicine, University of Bern, Bern, Switzerland
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Koichubekov BK, Sorokina MA, Laryushina YM, Turgunova LG, Korshukov IV. Nonlinear analyses of heart rate variability in hypertension. Ann Cardiol Angeiol (Paris) 2018; 67:174-179. [PMID: 29753421 DOI: 10.1016/j.ancard.2018.04.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 04/24/2018] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The autonomic nervous system plays an important role in blood pressure regulation and in the development of hypertension. Heart rate variability (HRV) may be of importance in identifying subjects at higher risk of developing hypertension. In the present study, comparative analysis of HRV for normal and hypertension subjects using nonlinear indices has been carried out. PATIENTS AND METHODS We analyzed the data from 24 patients with essential hypertension aged 45-55 (HG). All the subjects in this group had a confirmed diagnosis of the first- or second-stage essential hypertension. The control group for these subjects included 32 healthy volunteers of the same age group (CG). We analyzed the whole 5minutes of the ECG recording. Nonlinear indices D2, K2 and lagged Poincaré plot indices were calculated. RESULTS Values of D2 and K2 in hypertension state is statistically significantly lower than in healthy. Poincaré plot indices SD1 and SD2 in healthy volunteers are statistically higher than in hypertensive patients for all lags (P<0,05). SD1/SD2 ratio is also higher in healthy subjects, but the difference is statistically significant only for l=5 and 6. CONCLUSION The heart rhythm in groups with hypertension is more regular, its dynamics are less complex and less "chaotic," compared to healthy ones. This is expressed in lower values of entropy and correlation dimension. The HR stabilization is observed at both short and long time intervals, but mainly due to the decrease in the difference of the "neighboring" R-R intervals.
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Affiliation(s)
- B K Koichubekov
- Karaganda State Medical University, Gogol street 40, 100008 Karaganda, Kazakhstan.
| | - M A Sorokina
- Karaganda State Medical University, Gogol street 40, 100008 Karaganda, Kazakhstan.
| | - Y M Laryushina
- Karaganda State Medical University, Gogol street 40, 100008 Karaganda, Kazakhstan.
| | - L G Turgunova
- Karaganda State Medical University, Gogol street 40, 100008 Karaganda, Kazakhstan.
| | - I V Korshukov
- Karaganda State Medical University, Gogol street 40, 100008 Karaganda, Kazakhstan.
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Li P, Yu L, Lim ASP, Buchman AS, Scheer FAJL, Shea SA, Schneider JA, Bennett DA, Hu K. Fractal regulation and incident Alzheimer's disease in elderly individuals. Alzheimers Dement 2018; 14:1114-1125. [PMID: 29733807 PMCID: PMC6201319 DOI: 10.1016/j.jalz.2018.03.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 03/13/2018] [Accepted: 03/21/2018] [Indexed: 01/01/2023]
Abstract
Introduction: Healthy physiological systems exhibit fractal regulation (FR), generating similar fluctuation patterns in physiological outputs across different time scales. FR in motor activity is degraded in dementia, and the degradation correlates to cognitive decline. We tested whether degraded FR predicts Alzheimer’s dementia. Methods: FR in motor activity was assessed in 1097 nondemented older adults at baseline. Cognition was assessed annually for up to 11 years. Results: Participants with an FR metric at the 10th percentile in this cohort had a 1.8-fold Alzheimer’s disease risk (equivalent to the effect of being ~5.2 years older) and 1.3-fold risk for mild cognitive impairment (equivalent to the effect of being ~3.0 years older) than those at the 90th percentile. Consistently, degraded FR predicted faster cognitive decline. These associations were independent of physical activity, sleep fragmentation, and stability of daily activity rhythms. Discussion: FR may be a useful tool for predicting Alzheimer’s dementia.
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Affiliation(s)
- Peng Li
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Andrew S P Lim
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Aron S Buchman
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Frank A J L Scheer
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Steven A Shea
- Oregon Institute of Occupational Health Sciences, Oregon Health and Science University, Portland, OR, USA
| | - Julie A Schneider
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
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Assessment of Heart Rate Variability during an Endurance Mountain Trail Race by Multi-Scale Entropy Analysis. ENTROPY 2017. [DOI: 10.3390/e19120658] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Joustra SD, Gu C, Rohling JHT, Pickering L, Klose M, Hu K, Scheer FA, Feldt-Rasmussen U, Jennum PJ, Pereira AM, Biermasz NR, Meijer JH. Decrease in scale invariance of activity fluctuations with aging and in patients with suprasellar tumors. Chronobiol Int 2017; 35:368-377. [PMID: 29182371 PMCID: PMC5862770 DOI: 10.1080/07420528.2017.1407779] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Motor activity in healthy young humans displays intrinsic fluctuations that are scale-invariant over a wide range of time scales (from minutes to hours). Human postmortem and animal lesion studies showed that the intact function of the suprachiasmatic nucleus (SCN) is required to maintain such scale-invariant patterns. We therefore hypothesized that scale invariance is degraded in patients treated for suprasellar tumors that compress the SCN. To test the hypothesis, we investigated 68 patients with nonfunctioning pituitary macroadenoma and 22 patients with craniopharyngioma, as well as 72 age-matched healthy controls (age range 21.0–70.6 years). Spontaneous wrist locomotor activity was measured for 7 days with actigraphy, and detrended fluctuation analysis was applied to assess correlations over a range of time scales from minutes to 24 h. For all the subjects, complex scale-invariant correlations were only present for time scales smaller than 1.5 h, and became more random at time scales 1.5–10 h. Patients with suprasellar tumors showed a larger decrease in correlations at 1.5–10 h as compared to healthy controls. Within healthy subject, gender and age >33 year were associated with attenuated scale invariance. Conversely, activity patterns at time scales between 10 and 24 h were significantly more regular than all other time scales, and this was mostly associated with age. In conclusion, scale invariance is degraded in healthy subjects at the ages of >33 year as characterized by attenuation of correlations at time scales 1.5–10 h. In addition, scale invariance was more degraded in patients with suprasellar tumors as compared to healthy subjects.
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Affiliation(s)
- S D Joustra
- a Center for Endocrine Tumors Leiden, Department of Medicine, Division of Endocrinology , Leiden University Medical Center , Leiden , The Netherlands
| | - C Gu
- b Department of Molecular Cell Biology , Laboratory for Neurophysiology, Leiden University Medical Center , Leiden , The Netherlands.,c Business School , University of Shanghai for Science and Technology , Shanghai , China
| | - J H T Rohling
- b Department of Molecular Cell Biology , Laboratory for Neurophysiology, Leiden University Medical Center , Leiden , The Netherlands
| | - L Pickering
- d Department of Medical Endocrinology , Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark.,e Danish Center for Sleep Medicine , Neurophysiologic Clinic, Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - M Klose
- d Department of Medical Endocrinology , Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - K Hu
- f Division of Sleep and Circadian Disorders , Brigham and Women's Hospital , Boston , MA , USA.,g Division of Sleep Medicine , Harvard Medical School , Boston , MA , USA
| | - F A Scheer
- f Division of Sleep and Circadian Disorders , Brigham and Women's Hospital , Boston , MA , USA.,g Division of Sleep Medicine , Harvard Medical School , Boston , MA , USA
| | - U Feldt-Rasmussen
- d Department of Medical Endocrinology , Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - P J Jennum
- e Danish Center for Sleep Medicine , Neurophysiologic Clinic, Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - A M Pereira
- a Center for Endocrine Tumors Leiden, Department of Medicine, Division of Endocrinology , Leiden University Medical Center , Leiden , The Netherlands
| | - N R Biermasz
- a Center for Endocrine Tumors Leiden, Department of Medicine, Division of Endocrinology , Leiden University Medical Center , Leiden , The Netherlands
| | - J H Meijer
- b Department of Molecular Cell Biology , Laboratory for Neurophysiology, Leiden University Medical Center , Leiden , The Netherlands
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Ernst G. Hidden Signals-The History and Methods of Heart Rate Variability. Front Public Health 2017; 5:265. [PMID: 29085816 PMCID: PMC5649208 DOI: 10.3389/fpubh.2017.00265] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/14/2017] [Indexed: 12/18/2022] Open
Abstract
The understanding of heart rate variability (HRV) has increased parallel with the development of modern physiology. Discovered probably first in 1847 by Ludwig, clinical applications evolved in the second part of the twentieth century. Today HRV is mostly used in cardiology and research settings. In general, HRV can be measured over shorter (e.g., 5-10 min) or longer (12 or 24 h) periods. Since 1996, most measurements and calculations are made according to the standard of the Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. As the first step, the series of times between successive R-peaks in the ECG are in milliseconds. It is crucial, however, to identify and remove extrasystoles and artifacts according to standard protocols. The series of QRS distances between successive heartbeats can be analyzed with simple or more sophisticated algorithms, beginning with standard deviation (SDNN) or by the square root of the mean of the sum of squares of differences between adjacent normal RR (rMSSD). Short-term HRV is frequently analyzed with the help of a non-parametric fast Fourier transformation quantifying the different frequency bands during the measurement period. In the last decades, various non-linear algorithms have been presented, such as different entropy and fractal measures or wavelet analysis. Although most of them have a strong theoretical foundation, their clinical relevance is still debated.
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Affiliation(s)
- Gernot Ernst
- Anesthesiology, Pain and Palliative Care Section, Kongsberg Hospital, Vestre Viken Hospital Trust, Kongsberg, Norway
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Informative Nature and Nonlinearity of Lagged Poincaré Plots Indices in Analysis of Heart Rate Variability. ENTROPY 2017. [DOI: 10.3390/e19100523] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Lagged Poincaré plots have been successful in characterizing abnormal cardiac function. However, the current research practices do not favour any specific lag of Poincaré plots, thus complicating the comparison of results of different researchers in their analysis of heart rate of healthy subjects and patients. We researched the informative nature of lagged Poincaré plots in different states of the autonomic nervous system. It was tested in three models: different age groups, groups with different balance of autonomous regulation, and in hypertensive patients. Correlation analysis shows that for lag l = 6, SD1/SD2 has weak (r = 0.33) correlation with linear parameters of heart rate variability (HRV). For l more than 6 it displays even less correlation with linear parameters, but the changes in SD1/SD2 become statistically insignificant. Secondly, surrogate data tests show that the real SD1/SD2 is statistically different from its surrogate value and the conclusion could be made that the heart rhythm has nonlinear properties. Thirdly, the three models showed that for different functional states of the autonomic nervous system (ANS), SD1/SD2 ratio varied only for lags l = 5 and 6. All of this allow to us to give cautious recommendation to use SD1/SD2 with lags 5 and 6 as a nonlinear characteristic of HRV. The received data could be used as the basis for continuing the research in standardisation of nonlinear analytic methods.
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Yang Y, Aro AL, Nair SG, Jayaraman R, Reinier K, Rusinaru C, Uy-Evanado A, Yarmohammadi H, Jui J, Chugh SS. Novel measure of autonomic remodeling associated with sudden cardiac arrest in diabetes. Heart Rhythm 2017; 14:1449-1455. [PMID: 28711633 PMCID: PMC5624843 DOI: 10.1016/j.hrthm.2017.07.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Diabetes is independently associated with an increased risk of sudden cardiac arrest (SCA), with a need to identify novel methods for risk stratification. Diabetic patients can develop autonomic dysfunction that has been associated with an increased risk of ventricular arrhythmogenesis and manifests as reduced heart rate variability (HRV). However, previously published studies have not accounted for resting heart rate (HR), important from both pathophysiological and prognosticating standpoints. OBJECTIVE We sought to evaluate autonomic remodeling of the sinus node response in SCA and diabetes while accounting for HR. METHODS We performed a case-control study in SCA cases (age 35-59 years; 2002-2014) from the ongoing Oregon Sudden Unexpected Death Study (catchment population ∼1 million), and archived 12-lead electrocardiograms recorded prior to the SCA event were compared with those of geographic controls. Short-term HRV was calculated from digitized 10-second electrocardiograms by using established methods. We analyzed 313 subjects (mean age 52.0 ± 5.5 years; 216 men, 69.0%) and compared 4 groups: 111 diabetic (49 cases, 62 controls) and 202 nondiabetic (80 cases, 122 controls) subjects. RESULTS Analysis of covariance showed an absence of the expected interaction between HRV and HR (HRV-HR) in diabetic patients with SCA (regression slope -0.008; 95% confidence interval -0.023 to 0.0071; P = .26). This finding, unique to this population of diabetic patients with SCA, was not detected using traditional HRV measures. CONCLUSION By incorporating resting HR in this analysis, we observed that this population of diabetic patients with SCA had loss of the expected HRV-HR relationship. This potentially novel noninvasive risk measurement warrants further investigation, especially at the level of the individual patient.
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Affiliation(s)
- Yang Yang
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Aapo L Aro
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California; Heart and Lung Center, Helsinki University Hospital, Helsinki, Finland
| | - Sandeep G Nair
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Reshmy Jayaraman
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Kyndaron Reinier
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Carmen Rusinaru
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Audrey Uy-Evanado
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | | | - Jonathan Jui
- Oregon Health and Science University, Portland, Oregon
| | - Sumeet S Chugh
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
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de Andrade PE, do Amaral JAT, Paiva LDS, Adami F, Raimudo JZ, Valenti VE, Abreu LCD, Raimundo RD. Reduction of heart rate variability in hypertensive elderly. Blood Press 2017; 26:350-358. [PMID: 28738697 DOI: 10.1080/08037051.2017.1354285] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
INTRODUCTION The elderly population grows globally every day, and along with it the incidence of high blood pressure also grows, following these data scientists seek tools to improve the health of this population, a widely used tool for assessing cardiovascular function is the heart rate variability(HRV), that is a mecanism that allows the investigation of oscillations in the intervals between consecutive heart beats (RR intervals). There are already studies on the autonomic nervous system in the elderly population, however, these studies investigated normotensive patients and there is little research in hypertensive patients. AIM To compare the cardiac autonomic modulation between healthy elderly and hypertensive elderly. METHOD The total sample was 80 elderly people- 40 healthy elderly and 40 elderly (HBP). Anthropometric data, HRV analysis and IPAQ questionnaire were collected. For the analysis of cardiac modulation data in the time domain (pNN50, SDNN and RMSSD) and frequency domain (LF and HF). The geometric analysis (RRtri, TINN, SD1, SD2 and SD1/SD2 ratios). RESULTS In the time domain the MeanRR index presented a HAS increase 832.35 ± 104.46 ms vs control 782.73 ± 112.78 ms (p = 0.040). In the SDNN, there was a 58.35ms decrease vs the SAH 43.15 ms (p = 0.030). In the frequency domain, HF decreased control 247.00 ms2 vs HAS 157.00 ms2 (p = 0.002). In the geometric, the TINN and SD2 in the HAS group decreased in relation to the control from 203.38 ± 80.26 ms to 161.83 ± 53.25 ms (p = 0.018) and from 71.95 ms to 59.40 ms (p = 0.051). The mean SD1/SD2 ratio showed an increase between the Control and SAH groups from 0.22 ± 0.10 to 4.09 ± 1.18 and there was a statistical difference (p = 0.001). CONCLUSION Hypertensive elderly patients present decreased heart rate variability and decreased parasympathetic modulation when compared to normotensive elderly.
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Affiliation(s)
- Paulo Evaristo de Andrade
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil
| | - Joice Anaize Tonon do Amaral
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil.,b Faculdade de Medicina , Universidade de São Paulo-USP , São Paulo , SP , Brasil
| | - Laércio da Silva Paiva
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil.,c Laboratório de Epidemiologia e Análise de Dados , Faculdade de Medicina do ABC , Santo André , SP , Brasil
| | - Fernando Adami
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil.,c Laboratório de Epidemiologia e Análise de Dados , Faculdade de Medicina do ABC , Santo André , SP , Brasil
| | - Juliana Zangirolami Raimudo
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil
| | - Vitor Engrácia Valenti
- d Centro de Estudos do Sistema Nervoso Autônomo (CESNA), Programa de Pós-Graduação em Fisioterapia , UNESP Presidente Prudente , SP , Brasil
| | - Luiz Carlos de Abreu
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil
| | - Rodrigo Daminello Raimundo
- a Laboratório de Delineamento de Estudos e Escrita Científica , Faculdade de Medicina do ABC , Santo André , SP , Brasil
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Mazzuco A, Medeiros WM, Souza ASD, Alencar MCN, Neder JA, Borghi-Silva A. Are heart rate dynamics in the transition from rest to submaximal exercise related to maximal cardiorespiratory responses in COPD? Braz J Phys Ther 2017; 21:251-258. [PMID: 28558953 PMCID: PMC5537469 DOI: 10.1016/j.bjpt.2017.05.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 07/27/2016] [Accepted: 09/08/2016] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Poor exercise capacity is an important negative prognostic marker in patients with chronic obstructive pulmonary disease (COPD). Heart rate variability (HRV) responses can indicate alterations in cardiac autonomic control. Nevertheless, it remains unclear whether these abnormalities are related to cardiorespiratory responses to exercise in these patients. OBJECTIVE To evaluate whether HRV at rest and submaximal exercise are related to impaired cardiopulmonary responses to exercise in COPD patients. METHODS Fifteen men (66.2±8.7 years) with COPD (FEV1: 55.1±19.2%) were assessed. The R-R interval (RRi) data collection was performed at rest (stand position) and during the six-minute walk test (6MWT). All patients performed a symptom-limited cardiopulmonary exercise test on a cycle ergometer. The HRV changes from rest to submaximal exercise (Δ rest-6MWT) were calculated. RESULTS We found significant correlations between low frequency (LF) and high frequency (HF) Δ rest-6MWT with Δ oxyhemoglobin saturation by pulse oximetry (r=-0.64 and r=0.65, respectively; p<0.05), minute ventilation/carbon dioxide output relationship from beginning to peak exercise (r=-0.52 and r=0.53, p<0.05), and exercise ventilatory power (r=0.52 and r=-0.53, p<0.05). Interestingly, there was a strong positive correlation (r=0.82, p<0.05) between six-minute walk distance (6MWD) and Δ LF/HF from rest to exercise. CONCLUSION HRV analysis in the transition from rest to submaximal exercise is associated with exercise ventilatory and hemodynamic abnormalities in COPD patients. Rehabilitative strategies to improve HRV responses may provide an important tool to clinical practice in these patients.
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Affiliation(s)
- Adriana Mazzuco
- Laboratório de Fisioterapia Cardiopulmonar (LACAP), Universidade Federal de São Carlos (UFSCar), São Carlos, SP, Brazil
| | - Wladimir Musetti Medeiros
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício (SEFICE), Disciplina de Pneumologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Aline Soares de Souza
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício (SEFICE), Disciplina de Pneumologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Maria Clara Noman Alencar
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício (SEFICE), Disciplina de Pneumologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - José Alberto Neder
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício (SEFICE), Disciplina de Pneumologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil; Laboratory of Clinical Exercise Physiology (LACEP), Division of Respiratory and Critical Care Medicine, Department of Medicine, Queen's University, Kingston, Canada
| | - Audrey Borghi-Silva
- Laboratório de Fisioterapia Cardiopulmonar (LACAP), Universidade Federal de São Carlos (UFSCar), São Carlos, SP, Brazil.
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Fedotov AA, Akulova AS, Lebedev PA. Theoretical and clinical assessment of the sensitivity of heart rate variability indices. Biophysics (Nagoya-shi) 2017. [DOI: 10.1134/s0006350917040054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Lee CH, Lee JH, Son JW, Kim U, Park JS, Lee J, Shin DG. Normative Values of Short-Term Heart Rate Variability Parameters in Koreans and Their Clinical Value for the Prediction of Mortality. Heart Lung Circ 2017; 27:576-587. [PMID: 28592377 DOI: 10.1016/j.hlc.2017.04.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/15/2017] [Accepted: 04/20/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND Heart rate variability (HRV) analysis is an important clinical tool for characterising cardiac autonomic status. We sought to determine the normative values and characteristics of the HRV parameters derived from a short-term study in Koreans and to determine their clinical role in predicting mortality. METHODS A total of 1828 consecutive patients (range 20-84 years, men 64.8%) with no serious comorbid conditions were recruited. The RR intervals from 10-minute electrocardiograms were used for computation of the following HRV parameters: conventional time- and frequency-domain measures and nonlinear measures. RESULTS A greater age-dependence of most conventional parameters, including the low frequency (LF) and high frequency (HF) powers, was observed than that of the Shannon entropy (ShanEn), approximate entropy (ApEn), and sample entropy. Fifty-four patients (14 cardiac deaths) died during a 10-year follow-up period. The LF/HF ratio (odds ratio [OR], 0.876; p=0.025), ShanEn (OR, 0.372; p=0.028), and ApEn (OR, 0.093; p=0.030) were found to be predictors of all-cause mortality in the multivariate regression analysis. Age was also a powerful risk factor for all-cause mortality (OR, 1.141; p<0.001). CONCLUSIONS We presented the normative values and characterised the short-term HRV parameters in Koreans. Among the short-term nonlinear parameters, the ShanEn and ApEn were adjunctive parameters for predicting the all-cause mortality in the general population.
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Affiliation(s)
- Chan-Hee Lee
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea
| | - Jung-Hee Lee
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea
| | - Jang-Won Son
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea
| | - Ung Kim
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea
| | - Jong-Seon Park
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea
| | - Jeon Lee
- Department of Cell Biology, UT Southwestern Medical Center, Dallas Texas, USA
| | - Dong-Gu Shin
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea.
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50
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Fractal Based Analysis of the Influence of Odorants on Heart Activity. Sci Rep 2016; 6:38555. [PMID: 27929045 PMCID: PMC5144066 DOI: 10.1038/srep38555] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 11/09/2016] [Indexed: 12/15/2022] Open
Abstract
An important challenge in heart research is to make the relation between the features of external stimuli and heart activity. Olfactory stimulation is an important type of stimulation that affects the heart activity, which is mapped on Electrocardiogram (ECG) signal. Yet, no one has discovered any relation between the structures of olfactory stimuli and the ECG signal. This study investigates the relation between the structures of heart rate and the olfactory stimulus (odorant). We show that the complexity of the heart rate is coupled with the molecular complexity of the odorant, where more structurally complex odorant causes less fractal heart rate. Also, odorant having higher entropy causes the heart rate having lower approximate entropy. The method discussed here can be applied and investigated in case of patients with heart diseases as the rehabilitation purpose.
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