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Mercado L, Escalona-Vargas D, Siegel ER, Preissl H, Bolin EH, Eswaran H. Exploring the Influence of Fetal Sex on Heart Rate Dynamics Using Fetal Magnetocardiographic Recordings. Reprod Sci 2024; 31:823-831. [PMID: 37884730 DOI: 10.1007/s43032-023-01384-9] [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: 04/09/2023] [Accepted: 10/13/2023] [Indexed: 10/28/2023]
Abstract
Fetal sex has been associated with different development trajectories that cause structural and functional differences between the sexes throughout gestation. Fetal magnetocardiography (fMCG) recordings from 123 participants (64 females and 59 males; one recording/participant) from a database consisting of low-risk pregnant women were analyzed to explore and compare fetal development trajectories of both sexes. The gestational age of the recordings ranged from 28 to 38 weeks. Linear metrics in both the time and frequency domains were applied to study fetal heart rate variability (fHRV) measures that reveal the dynamics of short- and long-term variability. Rates of linear change with GA in these metrics were analyzed using general linear model regressions with assessments for significantly different variances and GA regression slopes between the sexes. The fetal sexes were well balanced for GA and sleep state. None of the fHRV measures analyzed exhibited significant variance heterogeneity between the sexes, and none of them exhibited a significant sex-by-GA interaction. The absence of a statistically significant sex-by-GA interaction on all parameters resulted in none of the regression slope estimates being significantly different between the sexes. With high-precision fMCG recordings, we were able to explore the variation in fHRV parameters as it relates to fetal sex. The fMCG-based fHRV parameters did not show any significant difference in rates of change with gestational age between sexes. This study provides a framework for understanding normal development of the fetal autonomic nervous system, especially in the context of fetal sex.
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Affiliation(s)
- Luis Mercado
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, 4301 W. Markham St, Little Rock, AR, 72205, USA
| | - Diana Escalona-Vargas
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, 4301 W. Markham St, Little Rock, AR, 72205, USA
- Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Research Institute, Little Rock, AR, USA
| | - Eric R Siegel
- Department of Biostatistics, University of Arkansas for Medical Sciences, 4301 W. Markham St, Little Rock, AR, 72205, USA
| | - Hubert Preissl
- Institute for Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the Eberhard Karls University of Tübingen, fMEG Center, Tübingen, Germany
| | - Elijah H Bolin
- Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Research Institute, Little Rock, AR, USA
| | - Hari Eswaran
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, 4301 W. Markham St, Little Rock, AR, 72205, USA.
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Nouri S, Kalantar MH, Safi F, Almasi-Hashiani A. The role of fetal heart rate in first trimester sonograms in prediction of fetal sex: a systematic review and meta-analysis. BMC Pregnancy Childbirth 2023; 23:582. [PMID: 37573392 PMCID: PMC10422800 DOI: 10.1186/s12884-023-05908-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 08/08/2023] [Indexed: 08/14/2023] Open
Abstract
BACKGROUND Early fetal sex determination is worthy of providing alertness about possible x-linked disorders, as well as predicting sex-related pregnancy complications and outcomes. Satisfying the curiosity of parents is another advantage. In this way, several studies have been performed which have shown conflicting results. AIM We planned a systematic review for identifying any plausible role of Fetal Heart Rate (FHR) for early predicting fetal sex during the first trimester of non-complicated pregnancies. METHODS This is a meta-analysis in which PubMed and Scopus databases were searched using different related keywords to find similar articles up to December 2022. Then the articles were screened to find eligible articles and finally, the articles entered in the meta-analysis were analyzed using Stata software (Stata Corp, College Station, TX). Standardized mean difference (SMD) and their 95% confidence interval (CI) were estimated. RESULTS A total of 223 articles were evaluated and five articles were included in the meta-analysis. The results showed that there is a significant heterogeneity between the articles (p = 0.012, I-squared = 69.0%). The results of meta-analysis with a random model showed that there is no significant difference between male and female genders in terms of mean FHR (SMD = 0.04, 95%CI = -0.09-0.16, Z = 0.59, p = 0.553). CONCLUSION This systematic review and meta-analysis showed that even though male fetuses show faster FHR but such sex-related difference is minimal. Therefore, first-trimester FHR is not a reliable predictive test for fetal sex determination. Further studies are recommended to achieve a more precise conclusion. TRIAL REGISTRATION PROSPERO: CRD42023418291.
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Affiliation(s)
- Shadi Nouri
- Department of Radiology, School of Medicine Arak, University of Medical Sciences, Arak, Iran
| | | | - Fatemeh Safi
- Department of Radiology, School of Medicine Arak, University of Medical Sciences, Arak, Iran
| | - Amir Almasi-Hashiani
- Department of Epidemiology, School of Health, Arak University of Medical Sciences, Arak, Iran
- Traditional and Complementary Medicine Research Center (TCMRC), Arak University of Medical Sciences, Arak, Iran
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3
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Massimello F, Billeci L, Canu A, Montt-Guevara MM, Impastato G, Varanini M, Giannini A, Simoncini T, Mannella P. Music Modulates Autonomic Nervous System Activity in Human Fetuses. Front Med (Lausanne) 2022; 9:857591. [PMID: 35492323 PMCID: PMC9046697 DOI: 10.3389/fmed.2022.857591] [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: 01/18/2022] [Accepted: 03/30/2022] [Indexed: 11/13/2022] Open
Abstract
ContextFetal Autonomic Nervous sysTem Evaluation (FANTE) is a non-invasive tool that evaluates the autonomic nervous system activity in a fetus. Autonomic nervous system maturation and development during prenatal life are pivotal for the survival and neuropsychiatric development of the baby.ObjectiveAim of the study is to evaluate the effect of music stimulation on fetal heart rate and specific parameters linked to ANS activity, in particular fetal heart rate variability.MethodsThirty-two women between the 32nd and 38th week with a singleton uncomplicated pregnancy were recruited. All FANTE data collections were acquired using a 10-derivation electrocardiograph placed on the maternal abdomen. In each session (5 min basal, 10 min with music stimulus, and 5 min post-stimulus), FANTE was registered. The music stimulus was “Clair de lune” Debussy, played through headphones on the mother’s abdomen (CTR: 31927).ResultsMusic does not change the mean value of fetal heart rate. However, indices of total fetal heart rate variability statistically increase (RRsd p = 0.037, ANNsd p = 0.039, SD2 p = 0.019) during music stimulation in comparison to the basal phase. Heart rate variability increase depends mainly on the activation of parasympathetic branches (CVI p = 0.013), meanwhile, no significant changes from basal to stimulation phase were observed for indices of sympathetic activity. All the parameters of heart rate variability and parasympathetic activity remained activated in the post-stimulus phase compared to the stimulus phase. In the post-stimulus phase, sympathetic activity resulted in a significant reduction (LFn p = 0.037).ConclusionMusic can influence the basal activity of the fetal autonomic nervous system, enhancing heart rate variability, without changing fetal heart rate mean value. Music is enabled to induce a relaxation state in a near-to-term fetus, mediated by parasympathetic activation and by a parallel sympathetic inhibition.
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Affiliation(s)
- Francesca Massimello
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Lucia Billeci
- Institute of Clinical Physiology, National Research Council of Italy (CNR-IFC), Pisa, Italy
| | - Alessio Canu
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | | | - Gaia Impastato
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Maurizio Varanini
- Institute of Clinical Physiology, National Research Council of Italy (CNR-IFC), Pisa, Italy
| | - Andrea Giannini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Tommaso Simoncini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Paolo Mannella
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
- *Correspondence: Paolo Mannella,
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Ponsiglione AM, Amato F, Romano M. Multiparametric Investigation of Dynamics in Fetal Heart Rate Signals. Bioengineering (Basel) 2021; 9:bioengineering9010008. [PMID: 35049717 PMCID: PMC8772900 DOI: 10.3390/bioengineering9010008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/15/2021] [Accepted: 12/21/2021] [Indexed: 11/16/2022] Open
Abstract
In the field of electronic fetal health monitoring, computerized analysis of fetal heart rate (FHR) signals has emerged as a valid decision-support tool in the assessment of fetal wellbeing. Despite the availability of several approaches to analyze the variability of FHR signals (namely the FHRV), there are still shadows hindering a comprehensive understanding of how linear and nonlinear dynamics are involved in the control of the fetal heart rhythm. In this study, we propose a straightforward processing and modeling route for a deeper understanding of the relationships between the characteristics of the FHR signal. A multiparametric modeling and investigation of the factors influencing the FHR accelerations, chosen as major indicator of fetal wellbeing, is carried out by means of linear and nonlinear techniques, blockwise dimension reduction, and artificial neural networks. The obtained results show that linear features are more influential compared to nonlinear ones in the modeling of HRV in healthy fetuses. In addition, the results suggest that the investigation of nonlinear dynamics and the use of predictive tools in the field of FHRV should be undertaken carefully and limited to defined pregnancy periods and FHR mean values to provide interpretable and reliable information to clinicians and researchers.
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Cerritelli F, Frasch MG, Antonelli MC, Viglione C, Vecchi S, Chiera M, Manzotti A. A Review on the Vagus Nerve and Autonomic Nervous System During Fetal Development: Searching for Critical Windows. Front Neurosci 2021; 15:721605. [PMID: 34616274 PMCID: PMC8488382 DOI: 10.3389/fnins.2021.721605] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/19/2021] [Indexed: 12/17/2022] Open
Abstract
The autonomic nervous system (ANS) is one of the main biological systems that regulates the body's physiology. Autonomic nervous system regulatory capacity begins before birth as the sympathetic and parasympathetic activity contributes significantly to the fetus' development. In particular, several studies have shown how vagus nerve is involved in many vital processes during fetal, perinatal, and postnatal life: from the regulation of inflammation through the anti-inflammatory cholinergic pathway, which may affect the functioning of each organ, to the production of hormones involved in bioenergetic metabolism. In addition, the vagus nerve has been recognized as the primary afferent pathway capable of transmitting information to the brain from every organ of the body. Therefore, this hypothesis paper aims to review the development of ANS during fetal and perinatal life, focusing particularly on the vagus nerve, to identify possible "critical windows" that could impact its maturation. These "critical windows" could help clinicians know when to monitor fetuses to effectively assess the developmental status of both ANS and specifically the vagus nerve. In addition, this paper will focus on which factors-i.e., fetal characteristics and behaviors, maternal lifestyle and pathologies, placental health and dysfunction, labor, incubator conditions, and drug exposure-may have an impact on the development of the vagus during the above-mentioned "critical window" and how. This analysis could help clinicians and stakeholders define precise guidelines for improving the management of fetuses and newborns, particularly to reduce the potential adverse environmental impacts on ANS development that may lead to persistent long-term consequences. Since the development of ANS and the vagus influence have been shown to be reflected in cardiac variability, this paper will rely in particular on studies using fetal heart rate variability (fHRV) to monitor the continued growth and health of both animal and human fetuses. In fact, fHRV is a non-invasive marker whose changes have been associated with ANS development, vagal modulation, systemic and neurological inflammatory reactions, and even fetal distress during labor.
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Affiliation(s)
- Francesco Cerritelli
- Research and Assistance for Infants to Support Experience Lab, Foundation Center for Osteopathic Medicine Collaboration, Pescara, Italy
| | - Martin G. Frasch
- Department of Obstetrics and Gynecology and Center on Human Development and Disability, University of Washington, Seattle, WA, United States
| | - Marta C. Antonelli
- Facultad de Medicina, Instituto de Biología Celular y Neurociencia “Prof. E. De Robertis”, Universidad de Buenos Aires, Buenos Aires, Argentina
- Department of Obstetrics and Gynecology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Chiara Viglione
- Research and Assistance for Infants to Support Experience Lab, Foundation Center for Osteopathic Medicine Collaboration, Pescara, Italy
| | - Stefano Vecchi
- Research and Assistance for Infants to Support Experience Lab, Foundation Center for Osteopathic Medicine Collaboration, Pescara, Italy
| | - Marco Chiera
- Research and Assistance for Infants to Support Experience Lab, Foundation Center for Osteopathic Medicine Collaboration, Pescara, Italy
| | - Andrea Manzotti
- Research and Assistance for Infants to Support Experience Lab, Foundation Center for Osteopathic Medicine Collaboration, Pescara, Italy
- Department of Pediatrics, Division of Neonatology, “V. Buzzi” Children's Hospital, Azienda Socio-Sanitaria Territoriale Fatebenefratelli Sacco, Milan, Italy
- Research Department, Istituto Osteopatia Milano, Milan, Italy
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6
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Zöllkau J, Swiderski L, Schmidt A, Weschenfelder F, Groten T, Hoyer D, Schneider U. The Relationship between Gestational Diabetes Metabolic Control and Fetal Autonomic Regulation, Movement and Birth Weight. J Clin Med 2021; 10:jcm10153378. [PMID: 34362160 PMCID: PMC8348724 DOI: 10.3390/jcm10153378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/13/2021] [Accepted: 07/26/2021] [Indexed: 12/03/2022] Open
Abstract
(1) Background: Maternal metabolic control in gestational diabetes is suggested to influence fetal autonomic control and movement activity, which may have fetal outcome implications. We aimed to analyze the relationship between maternal metabolic control, fetal autonomic heart rate regulation, activity and birth weight. (2) Methods: Prospective noninterventional longitudinal cohort monitoring study accompanying 19 patients with specialist clinical care for gestational diabetes. Monthly fetal magnetocardiography with electro-physiologically-based beat-to-beat heart rate recording for analysis of heart rate variability (HRV) and the ‘fetal movement index’ (FMI) was performed. Data were compared to 167 healthy pregnant women retrieved from our pre-existing study database. (3) Results: Fetal vagal tone was increased with gestational diabetes compared to controls, whereas sympathetic tone and FMI did not differ. Within the diabetic population, sympathetic activation was associated with higher maternal blood-glucose levels. Maternal blood-glucose levels correlated positively with birth weight z scores. FMI showed no correlation with birth weight but attenuated the positive correlation between maternal blood-glucose levels and birth weight. (4) Conclusion: Fetal autonomic control is altered by gestational diabetes and maternal blood-glucose level, even if metabolic adjustment and outcome is comparable to healthy controls.
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Affiliation(s)
- Janine Zöllkau
- Department of Obstetrics, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (L.S.); (F.W.); (T.G.); (U.S.)
- Correspondence:
| | - Laura Swiderski
- Department of Obstetrics, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (L.S.); (F.W.); (T.G.); (U.S.)
- Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (A.S.); (D.H.)
| | - Alexander Schmidt
- Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (A.S.); (D.H.)
| | - Friederike Weschenfelder
- Department of Obstetrics, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (L.S.); (F.W.); (T.G.); (U.S.)
| | - Tanja Groten
- Department of Obstetrics, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (L.S.); (F.W.); (T.G.); (U.S.)
| | - Dirk Hoyer
- Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (A.S.); (D.H.)
| | - Uwe Schneider
- Department of Obstetrics, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany; (L.S.); (F.W.); (T.G.); (U.S.)
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7
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Zwanenburg F, Jongbloed MRM, van Geloven N, Ten Harkel ADJ, van Lith JMM, Haak MC. Assessment of human fetal cardiac autonomic nervous system development using color tissue Doppler imaging. Echocardiography 2021; 38:974-981. [PMID: 34018638 PMCID: PMC8252470 DOI: 10.1111/echo.15094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 04/20/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022] Open
Abstract
Objectives Functional development of the fetal cardiac autonomic nervous system (cANS) plays a key role in fetal maturation and can be assessed through fetal heart rate variability (fHRV)‐analysis, with each HRV parameter representing different aspects of cANS activity. Current available techniques, however, are unable to assess the fHRV parameters accurately throughout the whole pregnancy. This study aims to test the feasibility of color tissue Doppler imaging (cTDI) as a new ultrasound technique for HRV analysis. Secondly, we explored time trends of fHRV parameters using this technique. Methods 18 healthy singleton fetuses were examined sequentially every 8 weeks from 10 weeks GA onwards. From each examination, 3 cTDI recordings of the four‐chamber view of 10 seconds were retrieved to determine accurate beat‐to‐beat intervals. The fHRV parameters SDNN, RMSSD, SDNN/RMSSD, and pNN10, each representing different functional aspects of the cANS, were measured, and time trends during pregnancy were explored using spline functions within a linear mixed‐effects model. Results In total, 77% (95% Cl 66–87%) of examinations were feasible for fHRV analysis from the first trimester onwards, which is a great improvement compared to other techniques. The technique is able to determine different maturation rates of the fHRV parameters, showing that cANS function, presumably parasympathetic activity, establishes around 20 weeks GA and matures rapidly until 30 weeks GA. Conclusions This is the first study able to assess cANS function through fHRV analysis from the first trimester onwards. The use of cTDI to determine beat‐to‐beat intervals seems feasible in just 3 clips of 10 seconds, which holds promise for future clinical use in assessing fetal well‐being.
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Affiliation(s)
- Fleur Zwanenburg
- Department of Obstetrics and Prenatal Diagnosis, Leiden University Medical Center, Leiden, The Netherlands
| | - Monique R M Jongbloed
- Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.,Department of Anatomy & Embryology, Leiden University Medical Center, Leiden, the Netherlands
| | - Nan van Geloven
- Department of Biomedical Data Sciences, Section Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands
| | - Arend D J Ten Harkel
- Department of Pediatric Cardiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jan M M van Lith
- Department of Obstetrics and Prenatal Diagnosis, Leiden University Medical Center, Leiden, The Netherlands
| | - Monique C Haak
- Department of Obstetrics and Prenatal Diagnosis, Leiden University Medical Center, Leiden, The Netherlands
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8
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The value of cardiorespiratory parameters for sleep state classification in preterm infants: A systematic review. Sleep Med Rev 2021; 58:101462. [PMID: 33826975 DOI: 10.1016/j.smrv.2021.101462] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 02/24/2021] [Accepted: 03/03/2021] [Indexed: 11/23/2022]
Abstract
Cardiorespiratory activity is highly associated with infants' sleep duration and quality. We performed a systematic literature search of PubMed and EMBASE databases to investigate if and how cardiorespiratory parameters can be used for sleep state classification in preterm infants and in what way maturation influences this relation. All retrieved citations were screened against predetermined inclusion and exclusion criteria. Only studies of preterm infants (<37 wk postmenstrual age during sleep state classification) admitted to a neonatal ward and of whom at least one sleep state and one cardiorespiratory parameter was measured, were included. Two researchers independently reviewed the included studies on methodological quality. Of the 1097 initially retrieved studies, 23 were included for analysis. Heart rate and respiration frequency are strongly correlated with active sleep and quiet sleep. In quiet sleep, as compared to active sleep, respiratory frequency is more stable, and the heart rate is lower and less variable. This association, however, differed across preterm birth subtypes (i.e., extremely, very or late preterm), indicating that maturation - in the form of both gestational and postnatal age - influences the cardiorespiratory characteristics of preterm sleep states. The knowledge gained from this review can help improve behavioral sleep classification and automated sleep classification algorithms for preterm infants.
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9
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Valderrama CE, Marzbanrad F, Hall-Clifford R, Rohloff P, Clifford GD. A Proxy for Detecting IUGR Based on Gestational Age Estimation in a Guatemalan Rural Population. Front Artif Intell 2020; 3:56. [PMID: 33733173 PMCID: PMC7861337 DOI: 10.3389/frai.2020.00056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 06/29/2020] [Indexed: 11/19/2022] Open
Abstract
In-utero progress of fetal development is normally assessed through manual measurements taken from ultrasound images, requiring relatively expensive equipment and well-trained personnel. Such monitoring is therefore unavailable in low- and middle-income countries (LMICs), where most of the perinatal mortality and morbidity exists. The work presented here attempts to identify a proxy for IUGR, which is a significant contributor to perinatal death in LMICs, by determining gestational age (GA) from data derived from simple-to-use, low-cost one-dimensional Doppler ultrasound (1D-DUS) and blood pressure devices. A total of 114 paired 1D-DUS recordings and maternal blood pressure recordings were selected, based on previously described signal quality measures. The average length of 1D-DUS recording was 10.43 ± 1.41 min. The min/median/max systolic and diastolic maternal blood pressures were 79/102/121 and 50.5/63.5/78.5 mmHg, respectively. GA was estimated using features derived from the 1D-DUS and maternal blood pressure using a support vector regression (SVR) approach and GA based on the last menstrual period as a reference target. A total of 50 trials of 5-fold cross-validation were performed for feature selection. The final SVR model was retrained on the training data and then tested on a held-out set comprising 28 normal weight and 25 low birth weight (LBW) newborns. The mean absolute GA error with respect to the last menstrual period was found to be 0.72 and 1.01 months for the normal and LBW newborns, respectively. The mean error in the GA estimate was shown to be negatively correlated with the birth weight. Thus, if the estimated GA is lower than the (remembered) GA calculated from last menstruation, then this could be interpreted as a potential sign of IUGR associated with LBW, and referral and intervention may be necessary. The assessment system may, therefore, have an immediate impact if coupled with suitable intervention, such as nutritional supplementation. However, a prospective clinical trial is required to show the efficacy of such a metric in the detection of IUGR and the impact of the intervention.
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Affiliation(s)
- Camilo E Valderrama
- Department of Biomedical Informatics, Emory University, Atlanta, GA, United States
| | - Faezeh Marzbanrad
- Department of Electrical and Computer Systems Engineering, Monash University, Melbourne, VIC, Australia
| | - Rachel Hall-Clifford
- Department of Sociology, Center for the Study of Human Health, Emory University, Atlanta, GA, United States
| | - Peter Rohloff
- Wuqu' Kawoq
- Maya Health Alliance, Santiago Sacatepéquez, Guatemala.,Division of Global Health Equity, Brigham and Women's Hospital, Boston, MA, United States
| | - Gari D Clifford
- Department of Biomedical Informatics, Emory University, Atlanta, GA, United States.,Department of Biomedical Engineering, Georgia Institute of Technology, Emory University, Atlanta, GA, United States
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10
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Mannella P, Billeci L, Giannini A, Canu A, Pancetti F, Simoncini T, Varanini M. A feasibility study on non-invasive fetal ECG to evaluate prenatal autonomic nervous system activity. Eur J Obstet Gynecol Reprod Biol 2020; 246:60-66. [PMID: 31962257 DOI: 10.1016/j.ejogrb.2020.01.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 01/07/2020] [Accepted: 01/11/2020] [Indexed: 12/18/2022]
Abstract
BACKGROUND Maturity of the autonomic nervous system (ANS) is of paramount importance for fetal adaptation to extrauterine life and for early neurological development. Markers of ANS maturity, such as electrophysiological heart rate parameters, are of interest as tools to determine prenatal fetal maturity. The available technology, fetal magnetocardiography is expensive and not suitable for clinical use. Detection of fetal electrocardiographic signals using traditional ECG leads on the maternal abdomen may be brought to the bedside, but is technically challenging. Our group has recently developed an innovative system consisting of a standard ECG with external leads applied on the maternal abdomen coupled with a software that extracts the fetal heart signal from the maternal noise. OBJECTIVE To validate the use of this innovative non-invasive system to detect fetal ECG (fECG) and its ability to detect changes in electrophysiological fetal cardiac parameters associated with ANS maturation. STUDY DESIGN we recruited 50 pregnant women between 24 and 41 weeks and they received non-invasive recording of fECG. RESULTS fECG was measurable at all gestational ages. Fetal heart rate variability (RR interval) and other associated parameters, such as low and high frequency increased with gestational age, particularly up to the 31st week. CONCLUSIONS This study shows that non-invasive fECG is feasible throughout a broad range of gestational ages and allows detecting electrophysiological parameters of the fetal heart that may be used a surrogate of ANS maturity. Technological implementation of this system and its further exploitation may generate new tool to estimate fetal maturity.
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Affiliation(s)
- Paolo Mannella
- Department of Clinical and Experimental Medicine, University of Pisa, Italy.
| | - Lucia Billeci
- Institute of Clinical Physiology (IFC) National Research Council (CNR), Pisa, Italy
| | - Andrea Giannini
- Department of Clinical and Experimental Medicine, University of Pisa, Italy
| | - Alessio Canu
- Department of Clinical and Experimental Medicine, University of Pisa, Italy
| | - Federica Pancetti
- Department of Clinical and Experimental Medicine, University of Pisa, Italy
| | - Tommaso Simoncini
- Department of Clinical and Experimental Medicine, University of Pisa, Italy
| | - Maurizio Varanini
- Institute of Clinical Physiology (IFC) National Research Council (CNR), Pisa, Italy
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11
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Nguyen TA, Chow T, Riggs W, Rurak D. Postnatal outcomes in lambs exposed antenatally and acutely postnatally to fluoxetine. Pediatr Res 2019; 85:1032-1040. [PMID: 30739124 DOI: 10.1038/s41390-019-0309-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 10/31/2018] [Accepted: 01/16/2019] [Indexed: 11/09/2022]
Abstract
BACKGROUND Approximately 1/3 of newborns exposed antenatally to selective serotonin reuptake inhibitors (SSRIs) exhibit poor neonatal adaptation. Although several potential mechanisms have been proposed, the actual mechanism has not been elucidated. METHODS We investigated outcomes in neonatal lambs exposed prenatally or postnatally to fluoxetine (FX). Daily FX injections (50 mg) were given intravenously (i.v.) to five pregnant ewes via implanted catheters beginning at 131-132 days gestation (term = 147 days) for 2 weeks. In another group, lambs with implanted vascular catheters had sterile water (n = 9) or FX (1 mg/kg, n = 12) injected i.v. on ~postnatal day (PND) 4. RESULTS Prenatal FX-exposed lambs (n = 7) were hyperactive during PND 4 to 14 and their heart rate variability (HRV) was significantly lower than in control lambs (n = 7) on PND 2. In contrast, arterial pressure, heart rate, electrocardiogram, arterial blood gases, pH, glucose, lactate, cortisol, and sleep-activity cycles were not altered following postnatal FX injection. CONCLUSION This abnormal postnatal hyperactivity with antenatal FX exposure may reflect increased maturity in terms of locomotory activity. The results suggest that altered brain development may be involved in the poor neonatal adaptation in human infants exposed to FX in utero.
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Affiliation(s)
- Tuan Anh Nguyen
- Department of Obstetrics and Gynecology, Faculty of Medicine, Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Timothy Chow
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Wayne Riggs
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Dan Rurak
- Department of Obstetrics and Gynecology, Faculty of Medicine, Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada.
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12
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Zavala JH, Ecklund-Flores L, Myers MM, Fifer WP. Assessment of autonomic function in the late term fetus: The effects of sex and state. Dev Psychobiol 2019; 62:224-231. [PMID: 31127614 DOI: 10.1002/dev.21865] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 04/06/2019] [Accepted: 04/12/2019] [Indexed: 11/09/2022]
Abstract
Researchers have reported associations between fetal sex and heart rate (FHR) and heart rate variability (FHRV) but rarely in the context of fetal behavioral sleep state. We examined differences in measures of fetal autonomic function by sex and sleep state. Fetal abdominal ECG monitoring technology was used to measure FHR and two measures of FHRV-standard deviation of FHR (SD) and beat-to-beat variability (RMSSD). FHR and movement patterns were also recorded with standard Doppler ultrasound monitor technology employed to code sleep states. Data were collected from 82 healthy fetuses ranging from 36 to 39 weeks gestation. A one-way MANOVA showed that FHR was significantly lower and SD was significantly higher for males than females. Independent samples t tests found that these sex differences were only in the active sleep state. There were no significant differences in RMSSD by sex. Repeated measures MANOVA for a subset that exhibited more than one state (N = 22) showed that SD was significantly different by state. RMSSD showed a marginally significant sleep state difference. In conclusion, fetal sex differences in HR and HRV may indicate more mature autonomic functioning in near-term males than females and fetal sleep state can influence abdominal fECG derived measures of FHR and FHRV.
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Affiliation(s)
- Julia H Zavala
- Department of Psychology, Mercy College, Dobbs Ferry, New York.,Division of Developmental Neuroscience, New York State Psychiatric Institute, New York, New York
| | - Lisa Ecklund-Flores
- Department of Psychology, Mercy College, Dobbs Ferry, New York.,Division of Developmental Neuroscience, New York State Psychiatric Institute, New York, New York
| | - Michael M Myers
- Division of Developmental Neuroscience, New York State Psychiatric Institute, New York, New York.,Department of Psychiatry, Columbia University, New York, New York.,Department of Pediatrics, Columbia University, New York, New York
| | - William P Fifer
- Division of Developmental Neuroscience, New York State Psychiatric Institute, New York, New York.,Department of Psychiatry, Columbia University, New York, New York.,Department of Pediatrics, Columbia University, New York, New York
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13
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Shuffrey LC, Myers MM, Odendaal HJ, Elliott AJ, du Plessis C, Groenewald C, Burd L, Angal J, Nugent JD, Isler JR, Fifer WP. Fetal heart rate, heart rate variability, and heart rate/movement coupling in the Safe Passage Study. J Perinatol 2019; 39:608-618. [PMID: 30833637 PMCID: PMC6483837 DOI: 10.1038/s41372-019-0342-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 01/19/2019] [Accepted: 01/30/2019] [Indexed: 12/17/2022]
Abstract
OBJECTIVE To determine normative values for heart rate patterns in healthy fetuses. METHODS This research is from the Safe Passage Study conducted by the Prenatal Alcohol and SIDS and Stillbirth (PASS) Network. A standardized protocol assessed fetal heart rate (FHR), heart rate variability (HRV), and movement from 1655 fetuses at three-time points during gestation (20-24 weeks, 28-32 weeks, 34-38 weeks gestation). RESULTS FHR decreased while HRV increased over gestation. At the latter two ages, males had significantly lower FHR than females while there were no sex differences in FHR at 20-24 weeks. When accounting for the fetal state during late gestation (34-28 weeks), we found that males had significantly lower FHR than females in the active fetal state only. CONCLUSION Results demonstrate significant state, gestational age, and sex-related changes in cardiac activity, somatic activity, and autonomic function as the fetus approaches birth.
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Affiliation(s)
- Lauren C. Shuffrey
- Department of Psychiatry, Columbia University Medical
Center, New York, NY 10032,Division of Developmental Neuroscience, New York State
Psychiatric Institute, New York, NY 10032
| | - Michael M. Myers
- Department of Psychiatry, Columbia University Medical
Center, New York, NY 10032,Division of Developmental Neuroscience, New York State
Psychiatric Institute, New York, NY 10032,Department of Pediatrics, Columbia University Medical
Center, New York, NY 10032
| | - Hein J. Odendaal
- Department of Obstetrics and Gynaecology, Faculty of
Medicine and Health Science, Stellenbosch University, Cape Town, Western Cape, South
Africa 7530
| | - Amy J. Elliott
- Center for Pediatric & Community Research, Avera
Research Institute, Sioux Falls, SD 57108,Department of Pediatrics, University of South Dakota School
of Medicine, Sioux Falls, SD 57105
| | - Carlie du Plessis
- Department of Obstetrics and Gynaecology, Faculty of
Medicine and Health Science, Stellenbosch University, Cape Town, Western Cape, South
Africa 7530
| | - Coen Groenewald
- Department of Obstetrics and Gynaecology, Faculty of
Medicine and Health Science, Stellenbosch University, Cape Town, Western Cape, South
Africa 7530
| | - Larry Burd
- Department of Pediatrics, University of North Dakota
Medical School, Grand Forks, ND 58202
| | - Jyoti Angal
- Center for Pediatric & Community Research, Avera
Research Institute, Sioux Falls, SD 57108,Department of Pediatrics, University of South Dakota School
of Medicine, Sioux Falls, SD 57105
| | - J. David Nugent
- Division of Developmental Neuroscience, New York State
Psychiatric Institute, New York, NY 10032
| | - Joseph R. Isler
- Division of Developmental Neuroscience, New York State
Psychiatric Institute, New York, NY 10032
| | - William P. Fifer
- Department of Psychiatry, Columbia University Medical
Center, New York, NY 10032,Division of Developmental Neuroscience, New York State
Psychiatric Institute, New York, NY 10032,Department of Pediatrics, Columbia University Medical
Center, New York, NY 10032
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14
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Zöllkau J, Dölker EM, Schmidt A, Schneider U, Hoyer D. Dependencies between maternal and fetal autonomic tone. J Perinat Med 2019; 47:323-330. [PMID: 30676005 DOI: 10.1515/jpm-2018-0221] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 10/30/2018] [Indexed: 11/15/2022]
Abstract
Background Disturbances in maternal physiology can cause changes in the fetal condition that may lead to impaired fetal development. Synchronous monitoring of cardiac autonomic tone via the assessment of the fetal and maternal heart rate (HR) and heart rate variability (HRV) may provide an appropriate diagnostic window. Methods Partial rank correlation coefficients between the maternal and fetal HR and HRV indices were calculated and verified by testing surrogate data in 315 magnetocardiographic (MCG) recordings from 141 healthy women pregnant with singleton fetuses [18+6 to 39+2 weeks gestational age (WGA)]. We assessed maternal self-perceived depression, anxiety and stress by means of the Depression, Anxiety, Stress Scales self-reporting instrument (DASS42G) questionnaire. Results The maternal HRV correlated positively with the fetal HRV, but negatively with the fetal HR. Correlation was |r|<0.2 in state-independent and gestational age (GA) <32 weeks, but |r|>0.2 in active sleep and GA ≥32 weeks. The DASS42G results correlated with the maternal HRV and HR, while the fetal HR and HRV were not influenced. Conclusion Correlations between maternal and fetal autonomic activation were statistically confirmed. They depend on the GA and active fetal state. As far as healthy subjects are concerned, maternal self-perceived stress, anxiety or depression is mirrored in maternal but not in fetal autonomic tone.
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Affiliation(s)
- Janine Zöllkau
- Department of Obstetrics and Gynecology, Jena University Hospital, Jena, Germany.,Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Eva-Maria Dölker
- Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany.,Institute of Biomedical Engineering and Informatics, Technical University Ilmenau, Ilmenau, Germany
| | - Alexander Schmidt
- Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Uwe Schneider
- Department of Obstetrics and Gynecology, Jena University Hospital, Jena, Germany
| | - Dirk Hoyer
- Biomagnetic Center, Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
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15
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Bhide A, Acharya G. Sex differences in fetal heart rate and variability assessed by antenatal computerized cardiotocography. Acta Obstet Gynecol Scand 2018; 97:1486-1490. [PMID: 30091138 DOI: 10.1111/aogs.13437] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/09/2018] [Accepted: 07/30/2018] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The aim of the current study is to explore the effect of fetal sex on the fetal heart rate and variability. MATERIAL AND METHODS This is a retrospective cross-sectional study. We analyzed fetal heart rate (FHR) traces of pregnant women that were recorded antenatally using a commercially available computerized cardiotocograph (cCTG; Oxford system). Fetal sex was ascertained after birth. Baseline FHR and short-term heart rate variation (STV) were compared between male and female fetuses. Expected mean values for baseline FHR and STV were computed and multiples of the mean (MOMean) of males and females were compared. RESULTS Information on 9259 cases is reported in this study. Baseline FHR of female fetuses was significantly higher (P < 0.001) and STV lower (P < 0.001) than that of male fetuses. This difference remained even after the effects of gestational age and diurnal variation were eliminated by computation of MOMean, but the absolute differences in the baseline FHR (0.9 beats/min [bpm]) and STV (0.246 ms) between male and female fetuses were small. A significant negative correlation was found between baseline FHR and STV (r = -0.518, P < 0.001). Similarly, a significant negative correlation was found between the MoMean of baseline FHR and MoMean STV (r = -0.481, P < 0.001). CONCLUSIONS Using the Oxford cCTG, male fetuses show a significantly lower baseline FHR and greater variability as compared with female fetuses. However, the absolute differences are small and may not be of major clinical significance.
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Affiliation(s)
- Amar Bhide
- Institute of Clinical and Molecular Sciences, St George's, University of London, London, UK.,Women's Health & Perinatal Research Group, Department of Clinical Medicine, UiT, The Arctic University of Norway, Tromsø, Norway
| | - Ganesh Acharya
- Women's Health & Perinatal Research Group, Department of Clinical Medicine, UiT, The Arctic University of Norway, Tromsø, Norway.,Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm, Sweden
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16
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Schneider U, Bode F, Schmidt A, Nowack S, Rudolph A, Doelcker EM, Schlattmann P, Götz T, Hoyer D. Developmental milestones of the autonomic nervous system revealed via longitudinal monitoring of fetal heart rate variability. PLoS One 2018; 13:e0200799. [PMID: 30016343 PMCID: PMC6049949 DOI: 10.1371/journal.pone.0200799] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 07/03/2018] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Fetal heart rate variability (fHRV) of normal-to-normal (NN) beat intervals provides high-temporal resolution access to assess the functioning of the autonomic nervous system (ANS). AIM To determine critical periods of fetal autonomic maturation. The developmental pace is hypothesized to change with gestational age (GA). STUDY DESIGN Prospective longitudinal observational study. SUBJECTS 60 healthy singleton fetuses were followed up by fetal magnetocardiographic heart rate monitoring 4-11 times (median 6) during the second half of gestation. OUTCOME MEASURE FHRV parameters, accounting for differential aspects of the ANS, were studied applying linear mixed models over four predefined pregnancy segments of interest (SoI: <27; 27+0-31+0; 31+1-35+0; >35+1 weeks GA). Periods of fetal active sleep and quiescence were accounted for separately. RESULTS Skewness of the NN interval distribution VLF/LF band power ratio and complexity describe a saturation function throughout the period of interest. A decreasing LF/HF ratio and an increase in pNN5 indicate a concurrent shift in sympathovagal balance. Fluctuation amplitude and parameters of short-term variability (RMSSD, HF band) mark a second acceleration towards term. In contrast, fetal quiescence is characterized by sequential, but low-margin transformations; ascending overall variability followed by an increase of complexity and superseded by fluctuation amplitude. CONCLUSIONS An increase in sympathetic activation, connected with by a higher ability of parasympathetic modulation and baseline stabilization, is reached during the transition from the late 2nd into the early 3rd trimester. Pattern characteristics indicating fetal well-being saturate at 35 weeks GA. Pronounced fetal breathing efforts near-term mirror in fHRV as respiratory sinus arrhythmia.
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Affiliation(s)
- Uwe Schneider
- Department of Obstetrics, Division of Prenatal Diagnostics and Fetal Physiology, Jena University Hospital, Jena, Germany
- * E-mail:
| | - Franziska Bode
- Department of Obstetrics, Division of Prenatal Diagnostics and Fetal Physiology, Jena University Hospital, Jena, Germany
| | - Alexander Schmidt
- Hans Berger Clinic of Neurology, Biomagnetic Center, Jena University Hospital, Jena, Germany
| | - Samuel Nowack
- Hans Berger Clinic of Neurology, Biomagnetic Center, Jena University Hospital, Jena, Germany
| | - Anja Rudolph
- Department of Obstetrics, Division of Prenatal Diagnostics and Fetal Physiology, Jena University Hospital, Jena, Germany
| | - Eva-Maria Doelcker
- Hans Berger Clinic of Neurology, Biomagnetic Center, Jena University Hospital, Jena, Germany
- Institute of Biomedical Engineering and Informatics, Technical University, Ilmenau, Germany
| | - Peter Schlattmann
- Institute for Medical Statistics, Computer and Data Sciences, Jena University Hospital, Jena, Germany
| | - Theresa Götz
- Hans Berger Clinic of Neurology, Biomagnetic Center, Jena University Hospital, Jena, Germany
- Institute for Medical Statistics, Computer and Data Sciences, Jena University Hospital, Jena, Germany
| | - Dirk Hoyer
- Hans Berger Clinic of Neurology, Biomagnetic Center, Jena University Hospital, Jena, Germany
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17
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Kapaya H, Jacques R, Anumba D. Comparison of diurnal variations, gestational age and gender related differences in fetal heart rate (FHR) parameters between appropriate-for-gestational-age (AGA) and small-for-gestational-age (SGA) fetuses in the home environment. PLoS One 2018. [PMID: 29522541 PMCID: PMC5844551 DOI: 10.1371/journal.pone.0193908] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Objective To assess the influence of gender, time of the day and gestational age on fetal heart rate (FHR) parameters between appropriate-for-gestational-age (AGA) and small-for-gestational age (SGA) fetuses using a portable fetal ECG monitor employed in the home setting. Methods We analysed and compared the antenatal FHR data collected in the home setting on 61 healthy pregnant women with singleton pregnancies from 24 weeks gestation. Of the 61 women, 31 had SGA fetuses (estimated fetal weight below the tenth gestational centile) and 30 were pregnant with AGA fetuses. FHR recordings were collected for up to 20 h. Two 90 min intervals were deliberately chosen retrospectively with respect to signal recording quality, one during day-time and one at night-time for comparison. Results Overall, success rate of the fetal abdominal ECG in the AGA fetuses was 75.7% compared to 48.6% in the SGA group. Based on randomly selected episodes of heart rate traces where recording quality exceeded 80% we were able to show a marginal difference between day and night-time recordings in AGA vs. SGA fetuses beyond 32 weeks of gestation. A selection bias in terms of covering different representation periods of fetal behavioural states cannot be excluded. In contrast to previous studies, we neither controlled maternal diet and activity nor measured maternal blood hormone and heart rate as all mothers were monitored in the home environment. Conclusion Based on clinically unremarkable, but statistically significant differences in the FHR parameters between the AGA and SGA group we suggest that further studies with large sample size are required to assess the clinical value of antenatal fetal ECG monitoring.
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Affiliation(s)
- Habiba Kapaya
- Department of Oncology and Metabolism, Academic Unit of Reproductive & Developmental Medicine, The University of Sheffield, Sheffield, United Kingdom
- * E-mail:
| | - Richard Jacques
- Medical Statistics Group, School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, United Kingdom
| | - Dilly Anumba
- Department of Oncology and Metabolism, Academic Unit of Reproductive & Developmental Medicine, The University of Sheffield, Sheffield, United Kingdom
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18
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Spyridou K, Chouvarda I, Hadjileontiadis L, Maglaveras N. Linear and nonlinear features of fetal heart rate on the assessment of fetal development in the course of pregnancy and the impact of fetal gender. Physiol Meas 2018; 39:015007. [PMID: 29185994 DOI: 10.1088/1361-6579/aa9e3c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE This work aims to investigate the impact of gestational age and fetal gender on fetal heart rate (FHR) tracings. APPROACH Different linear and nonlinear parameters indicating correlation or complexity were used to study the influence of fetal age and gender on FHR tracings. The signals were recorded from 99 normal pregnant women in a singleton pregnancy at gestational ages from 28 to 40 weeks, before the onset of labor. There were 56 female fetuses and 43 male. MAIN RESULTS Analysis of FHR shows that the means as well as measures of irregularity of FHR, such as approximate entropy and algorithmic complexity, decrease as gestation progresses. There were also indications that mutual information and multiscale entropy were lower in male fetuses in early pregnancy. SIGNIFICANCE Fetal age and gender seem to influence FHR tracings. Taking this into consideration would improve the interpretation of FHR monitoring.
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Affiliation(s)
- K Spyridou
- Laboratory of Computing, Medical Informatics and Biomedical Imaging Technologies, The Medical School, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece. Author to whom any correspondence should be addressed
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19
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Gonçalves H, Amorim-Costa C, Ayres-de-Campos D, Bernardes J. Evolution of linear and nonlinear fetal heart rate indices throughout pregnancy in appropriate, small for gestational age and preterm fetuses: A cohort study. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2018; 153:191-199. [PMID: 29157452 DOI: 10.1016/j.cmpb.2017.10.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 09/19/2017] [Accepted: 10/12/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND AND OBJECTIVES To assess the evolution of linear and nonlinear fetal heart rate (FHR) analysis throughout pregnancy in appropriate (AGA), small for gestational age (SGA) and preterm (PTB) fetuses. METHODS A prospective cohort study was carried out in 171 singleton pregnancies divided in three groups: AGA (n = 147), SGA (n = 13) fetuses and spontaneous PTB (n = 11). FHR was recorded with an external sensor from the 24th to the 40th week of gestation. Linear time- and frequency-domain and nonlinear FHR indices were computed on 10-min segments. Longitudinal analysis of indices throughout pregnancy was performed with generalized estimating equations, and receiver operating characteristic (ROC) curves were calculated for the prediction of SGA and PTB fetuses. RESULTS Increasing gestational age significantly affected most FHR indices, with a general increase in variability and entropy indices, and a decrease in mean FHR. The PTB group exhibited a significantly lower short-term variation, and no monotonic increase in the sympatho-vagal balance as observed in the AGA group. The SGA group exhibited higher long-term irregularity and lower short-term irregularity than the AGA group throughout gestation. In prediction of SGA and PTB, the largest areas under the ROC curves obtained were 0.76 and 0.78, respectively. CONCLUSIONS Linear and nonlinear FHR analysis provides useful information on the evolution of fetal autonomic nervous and complexity control systems throughout pregnancy, in relation with AGA, SGA and PTB fetuses, which may be helpful in clinical practice.
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Affiliation(s)
- Hernâni Gonçalves
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Portugal.
| | - Célia Amorim-Costa
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Portugal
| | - Diogo Ayres-de-Campos
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, São João Hospital, Porto, Portugal; INEB - Institute of Biomedical Engineering, I3S - Institute for Research and Innovation in Health, University of Porto, Portugal
| | - João Bernardes
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, São João Hospital, Porto, Portugal; Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Portugal
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20
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Estévez-Báez M, Carricarte-Naranjo C, Jas-García JD, Rodríguez-Ríos E, Machado C, Montes-Brown J, Leisman G, Schiavi A, Machado-García A, Luaces CS, Pié EA. Influence of Heart Rate, Age, and Gender on Heart Rate Variability in Adolescents and Young Adults. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1133:19-33. [PMID: 30414070 DOI: 10.1007/5584_2018_292] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Key autonomic functions are in continuous development during adolescence which can be assessed using the heart rate variability (HRV). However, the influence of different demographic and physiological factors on HRV indices has not been fully explored in adolescents. In this study we aimed to assess the effect of age, gender, and heart rate on HRV indices in two age groups of healthy adolescents (age ranges, 13-16 and 17-20 years) and two groups of healthy young adults (21-24 and 25-30 years). We addressed the issue using 5-min ECG recordings performed in the sitting position in 255 male and female participants. Time, frequency, and informational domains of HRV were calculated. Changes in HRV indices were assessed using a multiple linear regression model to adjust for the effects of heart rate, age, and gender. We found that heart rate produced more significant effects on HRV indices than age or gender. There was a progressive reduction in HRV with increasing age. Sympathetic influence increased with age and parasympathetic influence progressively decreased with age. The influence of gender was manifest only in younger adolescents and young adults. In conclusion, age, gender, and particularly heart rate have a substantial influence on HRV indices, which ought to be considered to avoid biases in the study of the autonomic nervous system development. The lack of the gender-related effects on HRV indices in late adolescence could be related to non-completely achieved maturity of the autonomic mechanisms, which deserves further exploration.
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Affiliation(s)
- Mario Estévez-Báez
- Institute of Neurology and Neurosurgery, Ministry of Health, Havana, Cuba
| | | | | | | | - Calixto Machado
- Institute of Neurology and Neurosurgery, Ministry of Health, Havana, Cuba
| | - Julio Montes-Brown
- Department of Medicine & Health Science, University of Sonora, Hermosillo, Mexico
| | - Gerry Leisman
- Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel. .,National Institute for Brain and Rehabilitation Sciences, Nazareth, Israel. .,Faculty 'Manuel Fajardo', University of the Medical Sciences, Havana, Cuba.
| | - Adam Schiavi
- Anesthesiology and Critical Care Medicine, Neurosciences Critical Care Division, Johns Hopkins Hospital, Baltimore, MD, USA
| | | | | | - Eduardo Arrufat Pié
- Institute of Basic and Preclinical Sciences "Victoria de Girón", Havana, Cuba
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21
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Romano M, Bifulco P, Ponsiglione A, Gargiulo G, Amato F, Cesarelli M. Evaluation of floatingline and foetal heart rate variability. Biomed Signal Process Control 2018. [DOI: 10.1016/j.bspc.2017.07.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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22
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Gonçalves H, Amorim-Costa C, Ayres-de-Campos D, Bernardes J. Gender-specific evolution of fetal heart rate variability throughout gestation: A study of 8823 cases. Early Hum Dev 2017; 115:38-45. [PMID: 28889037 DOI: 10.1016/j.earlhumdev.2017.09.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/29/2017] [Accepted: 09/05/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND Fetal heart rate (FHR) variability throughout gestation reflects aspects of fetal development, and its analysis has been used for the assessment of fetal well-being. AIM The objective of this study was to provide a gender-specific analysis of the evolution of FHR variability indices throughout gestation, using linear time-domain, spectral and nonlinear FHR indices. STUDY DESIGN A large retrospective study was carried out using antepartum FHR recordings obtained from 4713 male and 4110 female fetuses, with normal pregnancy outcome, between 2004 and 2013, with gestational ages ranging between 25 and 40weeks. OUTCOME MEASURES FHR variability was analysed through linear time-domain methods, as well as using spectral analysis and entropy indices. Evolution of FHR indices throughout gestation was analysed through Spearman correlation coefficient. Comparison between male and female fetuses was performed using nonparametric bootstrap 95% confidence intervals for the median. RESULTS Mean FHR decreased significantly throughout gestation, whereas most variability indices increased. Sympatho-vagal balance measured by spectral analysis exhibited two local maxima at 29-30 and 34-35weeks and decreased afterwards. Entropy indices increased until around the 34th week, slightly decreasing after the 37th week. Female fetuses presented higher mean FHR and entropy from the 34th week afterwards, and lower short-term variability and sympatho-vagal balance in the same period. CONCLUSIONS Spectral and entropy analysis should be considered as a complement to conventional FHR variability analysis, aiming at a better characterization and follow-up of fetal development/maturation throughout gestation. Additionally, gestational age needs to be considered when defining reference ranges for FHR indices in systems of computerized analysis.
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Affiliation(s)
- Hernâni Gonçalves
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Portugal.
| | - Célia Amorim-Costa
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Portugal; INEB - Institute of Biomedical Engineering, I3S - Institute for Research and Innovation in Health, University of Porto, Portugal
| | - Diogo Ayres-de-Campos
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Portugal; INEB - Institute of Biomedical Engineering, I3S - Institute for Research and Innovation in Health, University of Porto, Portugal; Department of Obstetrics and Gynecology, São João Hospital, Porto, Portugal
| | - João Bernardes
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Portugal; Department of Obstetrics and Gynecology, São João Hospital, Porto, Portugal; Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Portugal
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23
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Werth J, Long X, Zwartkruis-Pelgrim E, Niemarkt H, Chen W, Aarts RM, Andriessen P. Unobtrusive assessment of neonatal sleep state based on heart rate variability retrieved from electrocardiography used for regular patient monitoring. Early Hum Dev 2017; 113:104-113. [PMID: 28733087 DOI: 10.1016/j.earlhumdev.2017.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
As an approach of unobtrusive assessment of neonatal sleep state we aimed at an automated sleep state coding based only on heart rate variability obtained from electrocardiography used for regular patient monitoring. We analyzed active and quiet sleep states of preterm infants between 30 and 37weeks postmenstrual age. To determine the sleep states we used a nonlinear kernel support vector machine for sleep state separation based on known heart rate variability features. We used unweighted and weighted misclassification penalties for the imbalanced distribution between sleep states. The validation was performed with leave-one-out-cross-validation based on the annotations of three independent observers. We analyzed the classifier performance with receiver operating curves leading to a maximum mean value for the area under the curve of 0.87. Using this sleep state separation methods, we show that automated active and quiet sleep state separation based on heart rate variability in preterm infants is feasible.
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Affiliation(s)
- Jan Werth
- Department of Electrical Engineering, University of Technology Eindhoven, De Zaale, 5612 AJ, Eindhoven, The Netherlands; Philips Research, High Tech Campus 34, 5656 AE, Eindhoven, The Netherlands
| | - Xi Long
- Department of Electrical Engineering, University of Technology Eindhoven, De Zaale, 5612 AJ, Eindhoven, The Netherlands; Philips Research, High Tech Campus 34, 5656 AE, Eindhoven, The Netherlands.
| | | | - Hendrik Niemarkt
- Neonatal Intensive Care Unit, Maxima Medical Center, De Run 4600, 5504 DB, Veldhoven, The Netherlands
| | - Wei Chen
- Center for Intelligent Medical Electronics (CIME), School of Information Science and Technology, Department of Electronic Engineering, Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention, Fudan University, Shanghai 200433, China
| | - Ronald M Aarts
- Department of Electrical Engineering, University of Technology Eindhoven, De Zaale, 5612 AJ, Eindhoven, The Netherlands; Philips Research, High Tech Campus 34, 5656 AE, Eindhoven, The Netherlands
| | - Peter Andriessen
- Neonatal Intensive Care Unit, Maxima Medical Center, De Run 4600, 5504 DB, Veldhoven, The Netherlands; Faculty of Health, Medicine and Life Science, Maastricht University, Minderbroedersberg 4-6, 6211 LK Maastricht, The Netherlands.
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Gonçalves H, Fernandes D, Pinto P, Ayres-de-Campos D, Bernardes J. Simultaneous monitoring of maternal and fetal heart rate variability during labor in relation with fetal gender. Dev Psychobiol 2017; 59:832-839. [PMID: 28833043 DOI: 10.1002/dev.21554] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 07/17/2017] [Indexed: 11/07/2022]
Abstract
Male gender is considered a risk factor for several adverse perinatal outcomes. Fetal gender effect on fetal heart rate (FHR) has been subject of several studies with contradictory results. The importance of maternal heart rate (MHR) monitoring during labor has also been investigated, but less is known about the effect of fetal gender on MHR. The aim of this study is to simultaneously assess maternal and FHR variability during labor in relation with fetal gender. Simultaneous MHR and FHR recordings were obtained from 44 singleton term pregnancies during the last 2 hr of labor (H1, H2 ). Heart rate tracings were analyzed using linear (time- and frequency-domain) and nonlinear indices. Both linear and nonlinear components were considered in assessing FHR and MHR interaction, including cross-sample entropy (cross-SampEn). Mothers carrying male fetuses (n = 22) had significantly higher values for linear indices related with MHR average and variability and sympatho-vagal balance, while the opposite occurred in the high-frequency component and most nonlinear indices. Significant differences in FHR were only observed in H1 with higher entropy values in female fetuses. Assessing the differences between FHR and MHR, statistically significant differences were obtained in most nonlinear indices between genders. A significantly higher cross-SampEn was observed in mothers carrying female fetuses (n = 22), denoting lower synchrony or similarity between MHR and FHR. The variability of MHR and the synchrony/similarity between MHR and FHR vary with respect to fetal gender during labor. These findings suggest that fetal gender needs to be taken into account when simultaneously monitoring MHR and FHR.
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Affiliation(s)
- Hernâni Gonçalves
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal
| | - Diana Fernandes
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Paula Pinto
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Porto, Portugal
- Hospital Dr Nélio Mendonça, EPE, Funchal, Portugal
| | - Diogo Ayres-de-Campos
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Obstetrics and Gynecology, São João Hospital, Porto, Portugal
- INEB - Institute of Biomedical Engineering; I3S - Institute for Research and Innovation in Health, University of Porto, Porto, Portugal
| | - João Bernardes
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Obstetrics and Gynecology, São João Hospital, Porto, Portugal
- Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Senhora da Hora, Portugal
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Harrington JK, Sorabella R, Tercek A, Isler JR, Targoff KL. Nkx2.5 is essential to establish normal heart rate variability in the zebrafish embryo. Am J Physiol Regul Integr Comp Physiol 2017; 313:R265-R271. [PMID: 28615160 DOI: 10.1152/ajpregu.00223.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 06/02/2017] [Accepted: 06/06/2017] [Indexed: 12/11/2022]
Abstract
Heart rate variability (HRV) has become an important clinical marker of cardiovascular health and a research measure for the study of the cardiac conduction system and its autonomic controls. While the zebrafish (Danio rerio) is an ideal vertebrate model for understanding heart development, HRV has only recently been investigated in this system. We have previously demonstrated that nkx2.5 and nkx2.7, two homologues of Nkx2-5 expressed in zebrafish cardiomyocytes, play vital roles in maintaining cardiac chamber-specific characteristics. Given observed defects in ventricular and atrial chamber identities in nkx2.5-/- embryos coupled with conduction system abnormalities in murine models of Nkx2.5 insufficiency, we postulated that reduced HRV would serve as a marker of poor cardiac health in nkx2.5 mutants and in other zebrafish models of human congenital heart disease. Using live video image acquisition, we derived beat-to-beat intervals to compare HRV in wild-type and nkx2.5-/- embryos. Our data illustrate that the nkx2.5 loss-of-function model exhibits increased heart rate and decreased HRV when compared with wild type during embryogenesis. These findings validate HRV analysis as a useful quantitative tool for assessment of cardiac health in zebrafish and underscore the importance of nkx2.5 in maintaining normal heart rate and HRV during early conduction system development.
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Affiliation(s)
- Jamie K Harrington
- Division of Pediatric Cardiology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Robert Sorabella
- Division of Cardiothoracic Surgery, Department of Surgery, College of Physicians and Surgeons, Columbia University, New York, New York; and
| | - Abigail Tercek
- Division of Pediatric Cardiology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Joseph R Isler
- Division of Neonatology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Kimara L Targoff
- Division of Pediatric Cardiology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, New York;
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26
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Diurnal variations of short-term variation and the impact of multiple recordings on measurement accuracy. J Perinatol 2017; 37:231-235. [PMID: 27831546 DOI: 10.1038/jp.2016.202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 09/26/2016] [Accepted: 09/30/2016] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Short-term variation (STV) from computerized cardiotocogram heart rate analysis is a parameter that complements decision making, regarding the delivery of fetuses in several high-risk situations. Although studies on the effects of gestational age and fetal pathology are convincing, there is a lack of data exploring diurnal variation and the adequacy of a single measurement. STUDY DESIGN In this prospective observational study, fetal STV was monitored with the AN24 fetal ECG monitor (Monica Healthcare) each hour for at least 10 h in total, beginning at different times. This resulted in data covering all 24 h of the day. Seventy fetuses, low risk with respect to conditions accessible to heart rate monitoring (median 37th week of gestation) were monitored for an average of 12 h. Results of STV per hour were categorized as 'compromised' (STV<4 ms) or 'healthy', (STV⩾4 ms) to calculate the model of predictability. RESULTS The model proposed (STV of 'healthy' fetuses: 9.6±2.6 ms, 'compromised' fetuses 3.0±0.5 ms, prevalence 1%) leads to a positive predictive value of 39%, which increased to 68 or 80% given two or three pathological (STV<4 ms) measurements, respectively. Diurnal variation was not observed. CONCLUSIONS Single pathological STV values should be corroborated by further measurements in a 24-h interval in otherwise low-risk fetuses before inducing delivery. This may help to avoid unnecessary early births and give the fetus valuable days for intrauterine maturity.
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Fehlert E, Willmann K, Fritsche L, Linder K, Mat-Husin H, Schleger F, Weiss M, Kiefer-Schmidt I, Brucker S, Häring HU, Preissl H, Fritsche A. Gestational diabetes alters the fetal heart rate variability during an oral glucose tolerance test: a fetal magnetocardiography study. BJOG 2016; 124:1891-1898. [PMID: 28029217 DOI: 10.1111/1471-0528.14474] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2016] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Gestational diabetes mellitus (GDM) potentially harms the child before birth. We previously found GDM to be associated with developmental changes in the central nervous system. We now hypothesise that GDM may also impact on the fetal autonomic nervous system under metabolic stress like an oral glucose tolerance test (OGTT). DESIGN We measured heart rate variability (HRV) of mothers and fetuses during a three-point OGTT using fetal magnetocardiography (fMCG). SETTING Measurements were performed in the fMEG Centre in Tübingen. POPULATION After exclusion of 23 participants, 13 pregnant women with GDM and 36 pregnant women with normal glucose tolerance were examined. METHODS All women underwent the same examination setting with OGTT during which fMCG was recorded three times. MAIN OUTCOME MEASURE(S) Parameters of heart rate variability were measured. RESULTS Compared with mothers with normal glucose regulation, mothers with GDM showed increased heart rate but no significant differences of maternal HRV. In contrast, HRV in fetuses of mothers with GDM differed from those in the metabolically healthy group regarding standard deviation normal to normal beat (SDNN) (P = 0.012), low-frequency band (P = 0.008) and high-frequency band (P = 0.031). These HRV parameters exhibit a decrease only in GDM fetuses during the second hour of the OGTT. CONCLUSIONS These results show an altered response of the fetal autonomic nervous system to metabolic stress in GDM-complicated pregnancies. Hence, disturbances in maternal glucose metabolism might not only impact on the central nervous system of the fetus but may also affect the fetal autonomic nervous system. TWEETABLE ABSTRACT Metabolic stress reveals a different response of fetal autonomic nervous system in GDM-complicated pregnancies.
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Affiliation(s)
- E Fehlert
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany.,Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany
| | - K Willmann
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany
| | - L Fritsche
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany.,Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany
| | - K Linder
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany.,Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany
| | - H Mat-Husin
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany
| | - F Schleger
- Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany
| | - M Weiss
- Department of Obstetrics and Gynaecology, University Hospital, Eberhard Karls University, Tübingen, Germany
| | - I Kiefer-Schmidt
- Department of Obstetrics and Gynaecology, University Hospital, Eberhard Karls University, Tübingen, Germany
| | - S Brucker
- Department of Obstetrics and Gynaecology, University Hospital, Eberhard Karls University, Tübingen, Germany
| | - H-U Häring
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany.,Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany
| | - H Preissl
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany.,Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany.,Department of Pharmacy and Biochemistry, Institute of Pharmaceutical Sciences, Tübingen, Germany.,Interfaculty Centre for Pharmacogenomics and Pharma Research, Eberhard Karls Universität Tübingen, Tübingen, Germany.,Institute for Diabetes and Obesity, Helmholtz Diabetes Centre, Helmholtz Zentrum München, German Research Centre for Environmental Health (GmbH), Neuherberg, Germany
| | - A Fritsche
- Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Department of Internal Medicine, University Hospital, Eberhard Karls University, Tübingen, Germany.,Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany.,German Centre for Diabetes Research (DZD), Tübingen, Germany
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28
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Li G, Zhang S, Yang L, Li S, Wang Y, Hao D, Yang Y, Li X, Zhang L, Xu M. Computerized analysis of acceleration parameter for the non-stress test normal and potentially abnormal fetuses. Comput Assist Surg (Abingdon) 2016. [DOI: 10.1080/24699322.2016.1240293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Guangfei Li
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, PR China
| | - Song Zhang
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, PR China
| | - Lin Yang
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, PR China
| | - Shufang Li
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing, PR China
| | - Yan Wang
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing, PR China
| | - Dongmei Hao
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, PR China
| | - Yimin Yang
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, PR China
| | - Xuwen Li
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, PR China
| | - Lei Zhang
- Beijing Yes Medical Devices Co., Ltd, Beijing, PR China
| | - Mingzhou Xu
- Beijing Aerospace Changfeng Co., Ltd, Beijing, PR China
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29
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Seliger G, Stenzel A, Kowalski EM, Hoyer D, Nowack S, Seeger S, Schneider U. Evaluation of standardized, computerized Dawes/Redman heart-rate analysis based on different recording methods and in relation to fetal beat-to-beat heart rate variability. J Perinat Med 2016; 44:785-792. [PMID: 26584353 DOI: 10.1515/jpm-2015-0169] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 10/23/2015] [Indexed: 11/15/2022]
Abstract
Dawes and Redman (DR) based their definition of short-term variation (STV) on the successive differences of mean inter-beat intervals dividing 1 min of cardiotocography recordings in 16 epochs of 3.75 s each. In contrast, heart rate variability (HRV) is based on the inter-beat intervals of discrete R peaks, also referred to as normal-to-normal (NN) intervals. Despite the historical achievements of DR in providing a robust method with the equipment available at the time to encourage the widespread use and creation of large databases, one must ask whether the STV (DR) parameter is reproducible using a different method of recording, and how much temporal information is actually lost by applying the averaging algorithm sketched above. We simultaneously performed both standard Oxford cardiotocography and transabdominal fetal electrocardiography recordings in 26 patients with low-risk singletons. In addition, we revisited our database of 418 standard fetal magnetocardiographic recordings, applying the DR algorithm to the fetal NN data and compared them to standard HRV parameters. The correlation between STV (DR) from cardiotocography and fetal electrocardiography was stronger that of either with short term fHRV from NN intervals. The methodological trade-off to gain STV as a robust parameter from heart rate traces of limited temporal resolution is accompanied by a loss of temporal information that, at the moment, only fetal magnetocardiography and, to a lesser extent, fetal electrocardiography may provide.
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30
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Kapaya H, Broughton Pipkin F, Hayes-Gill B, Loughna PV. Circadian changes and sex-related differences in fetal heart rate parameters. Matern Health Neonatol Perinatol 2016; 2:9. [PMID: 27595008 PMCID: PMC5010766 DOI: 10.1186/s40748-016-0037-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/25/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Previous researchers have studied circadian changes in the fetal heart rate (FHR) on small sample sizes and in a strictly controlled environment. This study was undertaken to investigate these changes during the late second and third trimesters, using a portable fetal electrocardiogram recording device (Monica AN24) in pregnant women in home and hospital environments with unrestricted mobility. METHODS This was a prospective cohort study of 54 pregnant women with uncomplicated singleton pregnancies between 25 and 40 weeks gestation. FHR recordings were made up to 16 h at home or in the hospital setting in the United Kingdom. FHR data over 90 min periods were averaged and the day (7:00 am-11:00 pm) and night (11:00 pm-7:00 am) data from the same individual were compared. Data were examined for evidence of sex-related differences. RESULTS During the night, there was a significant reduction in basal heart rate (bFHR) and a significant increase in short term variation (STV) and long term variation (LTV) (P < 0.05). Basal FHR decreased (P < 0.002), whereas LTV increased (P = 0.014) with advancing gestation. Male fetuses showed greater day: night variation than females regardless of gestation (P = 0.014). There was a higher bFHR in fetuses monitored during the day in hospital (P = 0.04). CONCLUSION This study demonstrates that there are sex-, environment and time-related differences in the FHR parameters measured. These differences may need to be considered taken when interpreting FHR data.
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Affiliation(s)
- Habiba Kapaya
- Department of Oncology and Metabolism, Academic Unit of Reproductive & Developmental Medicine, 4th Floor Jessop Wing, Tree Root Walk, Sheffield, S102SF UK
| | - Fiona Broughton Pipkin
- Division of Child Health, Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham, NG7 2RD UK
| | - Barrie Hayes-Gill
- Electrical Systems and Optics Research Division, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Pamela V Loughna
- Division of Child Health, Obstetrics and Gynaecology, School of Medicine, University of Nottingham, Nottingham, NG7 2RD UK
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Li G, Zhang S, Yang L, Li S, Wang Y, Hao D, Yang Y, Li X, Zhang L, Xu M. Influence of gestational age and time of day in baseline and heart rate variation of fetuses. Technol Health Care 2016; 24 Suppl 2:S471-6. [PMID: 27163306 DOI: 10.3233/thc-161170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Fetal electrocardiography (FECG) places electrodes on the maternal abdomen to convert the fetal electrocardiosignals into fetal heart rate (FHR), improving the accuracy and comfort of pregnant woman. At the same time, FECG simplifies the procedure of long term monitoring in the perinatal period. OBJECTIVE Investigating the influence of gestational age and time of day on FHR features to distinguish between non-stress test (NST) normal fetuses and NST suspicious fetuses. METHODS A novel method of FHR baseline estimation was presented; then baseline value and fetal heart rate variation (FHRV) were analyzed in the time domain using FHR signals recorded from 52 fetuses. RESULTS Baseline values in 1:00, 2:00, 4:00, 5:00 and heart rate variation (HRV) distribution showed a significant difference (p< 0.05) between NST normal fetuses and NST suspicious fetuses. CONCLUSIONS The results suggest that NST normal and suspicious fetuses had same outcome and different FHR features. Accurately distinguishing normal fetuses and suspicious fetuses is important for lowering the false positive rate and reducing unnecessary clinical intervention.
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Affiliation(s)
- Guangfei Li
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, China
| | - Song Zhang
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, China
| | - Lin Yang
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, China
| | - Shufang Li
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
| | - Yan Wang
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
| | - Dongmei Hao
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, China
| | - Yimin Yang
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, China
| | - Xuwen Li
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, China
| | - Lei Zhang
- Beijing Yes Medical Devices Co., Ltd., Beijing, China
| | - Mingzhou Xu
- Beijing Aerospace ChangFeng Co., Ltd., Beijing, China
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Romano M, Iuppariello L, Ponsiglione AM, Improta G, Bifulco P, Cesarelli M. Frequency and Time Domain Analysis of Foetal Heart Rate Variability with Traditional Indexes: A Critical Survey. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2016; 2016:9585431. [PMID: 27195018 PMCID: PMC4852340 DOI: 10.1155/2016/9585431] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 03/06/2016] [Accepted: 03/07/2016] [Indexed: 11/17/2022]
Abstract
Monitoring of foetal heart rate and its variability (FHRV) covers an important role in assessing health of foetus. Many analysis methods have been used to get quantitative measures of FHRV. FHRV has been studied in time and in frequency domain and interesting clinical results have been obtained. Nevertheless, a standardized definition of FHRV and a precise methodology to be used for its evaluation are lacking. We carried out a literature overview about both frequency domain analysis (FDA) and time domain analysis (TDA). Then, by using simulated FHR signals, we defined the methodology for FDA. Further, employing more than 400 real FHR signals, we analysed some of the most common indexes, Short Term Variability for TDA and power content of the spectrum bands and sympathovagal balance for FDA, and evaluated their ranges of values, which in many cases are a novelty. Finally, we verified the relationship between these indexes and two important parameters: week of gestation, indicator of foetal growth, and foetal state, classified as active or at rest. Our results indicate that, according to literature, it is necessary to standardize the procedure for FHRV evaluation and to consider week of gestation and foetal state before FHR analysis.
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Affiliation(s)
- Maria Romano
- DMSC, University “Magna Graecia”, Catanzaro, Italy
| | | | | | - Giovanni Improta
- Department of Public Health, University of Naples “Federico II” Hospital, Naples, Italy
| | - Paolo Bifulco
- DIETI, University of Naples “Federico II”, Naples, Italy
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Sex-related differences in the development of fetal heart rate dynamics. Early Hum Dev 2016; 93:47-55. [PMID: 26789556 DOI: 10.1016/j.earlhumdev.2015.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/15/2015] [Accepted: 12/18/2015] [Indexed: 11/20/2022]
Abstract
BACKGROUND Despite previous efforts to explain the general advantages of female fetuses over males regarding health, sex-related differences in the dynamics or complexity of fetal heart rate (FHR) variability and FHR maturation patterns have not yet been identified. AIM To make linear and nonlinear comparisons of antepartum FHR indices, dynamics, complexity, and reactivity to the non-stress test (NST) and vibroacoustic-stimulation test (VAST) in male and female fetuses. STUDY DESIGN A total of 3835 singleton term deliveries without maternal and fetal complications were divided into female (n=1849) and male (n=1986) groups, and subjected to comparison and analyses. SUBJECTS Linear FHR indices, approximate entropy (ApEn), sample entropy (SampEn), short-term/long-term exponents (α1/α2), correlation dimension (CD), NST and VAST criteria, and modified nonlinear reactive criteria (MNRC) were used to evaluate outcomes. RESULTS ApEn was consistently higher in female fetuses than in male ones. ApEn in female fetuses was maximal at 29-30 gestational weeks, while the increase in ApEn was delayed in male fetuses but more rapid, reaching its peak at 31-32 gestational weeks. In both sexes, CD increased up to term, and α2 rapidly decreased up to 31-32weeks in an analogous manner. The two sexes differed significantly in response to VAST at <31 gestational weeks and there was a structural difference in reactive patterns under MNRC. CONCLUSIONS Female fetuses exhibit greater heart rate dynamics in early gestational periods, suggesting that their cardiovascular system matures earlier than that of males. Male fetuses undergo a compensatory period of rapid change to catch up with females at term.
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DiPietro JA, Costigan KA, Voegtline KM. STUDIES IN FETAL BEHAVIOR: REVISITED, RENEWED, AND REIMAGINED. Monogr Soc Res Child Dev 2015; 80:vii;1-94. [PMID: 26303396 DOI: 10.1111/mono.v80.3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Among the earliest volumes of this monograph series was a report by Lester Sontag and colleagues, of the esteemed Fels Institute, on the heart rate of the human fetus as an expression of the developing nervous system. Here, some 75 years later, we commemorate this work and provide historical and contemporary context on knowledge regarding fetal development, as well as results from our own research. These are based on synchronized monitoring of maternal and fetal parameters assessed between 24 and 36 weeks gestation on 740 maternal-fetal pairs compiled from eight separate longitudinal studies, which commenced in the early 1990s. Data include maternal heart rate, respiratory sinus arrhythmia, and electrodrmal activity and fetal heartrate, motor activity, and their integration. Hierarchical linear modeling of developmental trajectories reveals that the fetus develops in predictable ways consistent with advancing parasympathetic regulation. Findings also include:within-fetus stability (i.e., preservation of rank ordering over time) for heart rate, motor, and coupling measures; a transitional period of decelerating development near 30 weeks gestation; sex differences in fetal heart rate measures but not in most fetal motor activity measures; modest correspondence in fetal neurodevelopment among siblings as compared to unrelated fetuses; and deviations from normative fetal development in fetuses affected by intrauterine growth restriction and other conditions. Maternal parameters also change during this period of gestation and there is evidence that fetal sex and individual variation in fetal neurobehavior influence maternal physio-logical processes and the local intrauterine context. Results are discussed within the framework of neuromaturation, the emergence of individual differences, and the bidirectional nature of the maternal-fetal relationship.We pose a number of open questions for future research. Although the human fetus remains just out of reach, new technologies portend an era of accelerated discovery of the earliest period of development
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Karmakar C, Kimura Y, Palaniswami M, Khandoker A. Analysis of fetal heart rate asymmetry before and after 35 weeks of gestation. Biomed Signal Process Control 2015. [DOI: 10.1016/j.bspc.2015.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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DiPietro JA, Voegtline KM. The gestational foundation of sex differences in development and vulnerability. Neuroscience 2015; 342:4-20. [PMID: 26232714 DOI: 10.1016/j.neuroscience.2015.07.068] [Citation(s) in RCA: 176] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 01/06/2023]
Abstract
Despite long-standing interest in the role of sex on human development, the functional consequences of fetal sex on early development are not well-understood. Here we explore the gestational origins of sex as a moderator of development. In accordance with the focus of this special issue, we examine evidence for a sex differential in vulnerability to prenatal and perinatal risks. Exposures evaluated include those present in the external environment (e.g., lead, pesticides), those introduced by maternal behaviors (e.g., alcohol, opioid use), and those resulting from an adverse intrauterine environment (e.g., preterm birth). We also provide current knowledge on the degree to which sex differences in fetal neurobehavioral development (i.e., cardiac and motor patterns) are present prior to birth. Also considered are contemporaneous and persistent sex of fetus effects on the pregnant woman. Converging evidence confirms that infant and early childhood developmental outcomes of male fetuses exposed to prenatal and perinatal adversities are more highly impaired than those of female fetuses. In certain circumstances, male fetuses are both more frequently exposed to early adversities and more affected by them when exposed than are female fetuses. The mechanisms through which biological sex imparts vulnerability or protection on the developing nervous system are largely unknown. We consider models that implicate variation in maturation, placental functioning, and the neuroendocrine milieu as potential contributors. Many studies use sex as a control variable, some analyze and report main effects for sex, but those that report interaction terms for sex are scarce. As a result, the true scope of sex differences in vulnerability is unknown.
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Affiliation(s)
- J A DiPietro
- Department of Population, Family, and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - K M Voegtline
- Department of Population, Family, and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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REFERENCES. Monogr Soc Res Child Dev 2015. [DOI: 10.1111/mono.12184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Guyon L, Auffret M, Coussemacq M, Béné J, Deruelle P, Gautier S. Alteration of the Fetal Heart Rate Pattern Induced by the Use Of Clozapine during Pregnancy. Therapie 2015; 70:301-3. [DOI: 10.2515/therapie/2014214] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 10/06/2014] [Indexed: 11/20/2022]
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Brändle J, Preissl H, Draganova R, Ortiz E, Kagan KO, Abele H, Brucker SY, Kiefer-Schmidt I. Heart rate variability parameters and fetal movement complement fetal behavioral states detection via magnetography to monitor neurovegetative development. Front Hum Neurosci 2015; 9:147. [PMID: 25904855 PMCID: PMC4388008 DOI: 10.3389/fnhum.2015.00147] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/02/2015] [Indexed: 11/13/2022] Open
Abstract
Fetal behavioral states are defined by fetal movement and heart rate variability (HRV). At 32 weeks of gestational age (GA) the distinction of four fetal behavioral states represented by combinations of quiet or active sleep or awakeness is possible. Prior to 32 weeks, only periods of fetal activity and quiesence can be distinguished. The increasing synchronization of fetal movement and HRV reflects the development of the autonomic nervous system (ANS) control. Fetal magnetocardiography (fMCG) detects fetal heart activity at high temporal resolution, enabling the calculation of HRV parameters. This study combined the criteria of fetal movement with the HRV analysis to complete the criteria for fetal state detection. HRV parameters were calculated including the standard deviation of the normal-to-normal R–R interval (SDNN), the mean square of successive differences of the R–R intervals (RMSSD, SDNN/RMSSD ratio, and permutation entropy (PE) to gain information about the developing influence of the ANS within each fetal state. In this study, 55 magnetocardiograms from healthy fetuses of 24–41 weeks’ GA were recorded for up to 45 min using a fetal biomagnetometer. Fetal states were classified based on HRV and movement detection. HRV parameters were calculated for each state. Before GA 32 weeks, 58.4% quiescence and 41.6% activity cycles were observed. Later, 24% quiet sleep state (1F), 65.4% active sleep state (2F), and 10.6% active awake state (4F) were observed. SDNN increased over gestation. Changes of HRV parameters between the fetal behavioral states, especially between 1F and 4F, were statistically significant. Increasing fetal activity was confirmed by a decrease in PE complexity measures. The fHRV parameters support the differentiation between states and indicate the development of autonomous nervous control of heart rate function.
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Affiliation(s)
- Johanna Brändle
- University Women's Hospital and Research Institute for Women's Health, University of Tuebingen Tuebingen, Germany ; fMEG Center, University of Tuebingen Tuebingen, Germany ; Department of Obstetrics and Gynecology, University of Tuebingen Tuebingen, Germany
| | | | | | - Erick Ortiz
- fMEG Center, University of Tuebingen Tuebingen, Germany
| | - Karl O Kagan
- Department of Obstetrics and Gynecology, University of Tuebingen Tuebingen, Germany
| | - Harald Abele
- Department of Obstetrics and Gynecology, University of Tuebingen Tuebingen, Germany
| | - Sara Y Brucker
- University Women's Hospital and Research Institute for Women's Health, University of Tuebingen Tuebingen, Germany ; Department of Obstetrics and Gynecology, University of Tuebingen Tuebingen, Germany
| | - Isabelle Kiefer-Schmidt
- University Women's Hospital and Research Institute for Women's Health, University of Tuebingen Tuebingen, Germany ; fMEG Center, University of Tuebingen Tuebingen, Germany ; Department of Obstetrics and Gynecology, University of Tuebingen Tuebingen, Germany
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Porta A, Bari V, Marchi A, De Maria B, Cysarz D, Van Leeuwen P, Takahashi ACM, Catai AM, Gnecchi-Ruscone T. Complexity analyses show two distinct types of nonlinear dynamics in short heart period variability recordings. Front Physiol 2015; 6:71. [PMID: 25806002 PMCID: PMC4354335 DOI: 10.3389/fphys.2015.00071] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 02/20/2015] [Indexed: 11/30/2022] Open
Abstract
Two diverse complexity metrics quantifying time irreversibility and local prediction, in connection with a surrogate data approach, were utilized to detect nonlinear dynamics in short heart period (HP) variability series recorded in fetuses, as a function of the gestational period, and in healthy humans, as a function of the magnitude of the orthostatic challenge. The metrics indicated the presence of two distinct types of nonlinear HP dynamics characterized by diverse ranges of time scales. These findings stress the need to render more specific the analysis of nonlinear components of HP dynamics by accounting for different temporal scales.
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Affiliation(s)
- Alberto Porta
- Laboratory of Complex System Modeling, Department of Biomedical Sciences for Health, University of Milan Milan, Italy ; IRCCS Galeazzi Orthopedic Institute Milan, Italy
| | - Vlasta Bari
- Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato Milan, Italy
| | - Andrea Marchi
- Department of Anesthesia and Intensive Care Unit, Humanitas Clinical and Research Center Rozzano, Italy
| | | | - Dirk Cysarz
- Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke Witten, Germany ; Department of Medicine, Institute for Integrative Medicine, University of Witten/Herdecke Herdecke, Germany
| | - Peter Van Leeuwen
- Department of Biomagnetism, Grönemeyer Institute for Microtherapy, University of Witten/Herdecke Bochum, Germany
| | - Anielle C M Takahashi
- Research Laboratory in Health Elderly, Department of Physiotherapy, Federal University of São Carlos São Carlos, Brazil ; Cardiovascular Physiotherapy Laboratory, Department of Physiotherapy, Nucleus of Research in Physical Exercise, Federal University of São Carlos São Carlos, Brazil
| | - Aparecida M Catai
- Cardiovascular Physiotherapy Laboratory, Department of Physiotherapy, Nucleus of Research in Physical Exercise, Federal University of São Carlos São Carlos, Brazil
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Tendais I, Figueiredo B, Gonçalves H, Bernardes J, Ayres-de-Campos D, Montenegro N. Sex differences in the fetal heart rate variability indices of twins. J Perinat Med 2015; 43:221-5. [PMID: 24945419 DOI: 10.1515/jpm-2014-0031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 05/23/2014] [Indexed: 11/15/2022]
Abstract
AIMS To evaluate the differences in linear and complex heart rate dynamics in twin pairs according to fetal sex combination [male-female (MF), male-male (MM), and female-female (FF)]. METHODS Fourteen twin pairs (6 MF, 3 MM, and 5 FF) were monitored between 31 and 36.4 weeks of gestation. Twenty-six fetal heart rate (FHR) recordings of both twins were simultaneously acquired and analyzed with a system for computerized analysis of cardiotocograms. Linear and nonlinear FHR indices were calculated. RESULTS Overall, MM twins presented higher intrapair average in linear indices than the other pairs, whereas FF twins showed higher sympathetic-vagal balance. MF twins exhibited higher intrapair average in entropy indices and MM twins presented lower entropy values than FF twins considering the (automatically selected) threshold rLu. MM twin pairs showed higher intrapair differences in linear heart rate indices than MF and FF twins, whereas FF twins exhibited lower intrapair differences in entropy indices. CONCLUSIONS The results of this exploratory study suggest that twins have sex-specific differences in linear and nonlinear indices of FHR. MM twins expressed signs of a more active autonomic nervous system and MF twins showed the most active complexity control system. These results suggest that fetal sex combination should be taken into consideration when performing detailed evaluation of the FHR in twins.
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Cysarz D, Edelhäuser F, Van Leeuwen P. Strategies of symbolization in cardiovascular time series to test individual gestational development in the fetus. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2015; 373:rsta.2014.0087. [PMID: 25548263 DOI: 10.1098/rsta.2014.0087] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The analysis of symbolic dynamics applied to physiological time series retrieves dynamical properties of the underlying regulation which are robust against the symbolic transformation. In this study, three different transformations to produce a symbolic series were applied to fetal RR interval series to test whether they reflect individual changes of fetal heart rate variability in the course of pregnancy. Each transformation was applied to 215 heartbeat datasets obtained from 11 fetuses during the second and the third trimester of pregnancy (at least 10 datasets per fetus, median 17). In the symbolic series, the occurrence of symbolic sequences of length 3 was categorized according to the amount of variations in the sequence: no variation of the symbols, one variation, two variations. Linear regression with respect to gestational age showed that the individual course during pregnancy performed best using a binary transformation reflecting whether the RR interval differences are below or above a threshold. The median goodness of fit of the individual regression lines was 0.73 and also the variability among the individual slopes was low. Other transformations to symbolic dynamics performed worse but were still able to reflect the individual progress of fetal cardiovascular regulation.
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Affiliation(s)
- Dirk Cysarz
- Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, Witten, Germany Institute of Integrative Medicine, University of Witten/Herdecke, Witten, Germany
| | - Friedrich Edelhäuser
- Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, Witten, Germany Institute of Integrative Medicine, University of Witten/Herdecke, Witten, Germany
| | - Peter Van Leeuwen
- Department of Biomagnetism, Grönemeyer Institute for Microtherapy, University of Witten/Herdecke, Witten, Germany
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Karmakar C, Khandoker A, Kimura Y, Palaniswami M. Investigating foetal heart rate asymmetry. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2014:2261-4. [PMID: 25570438 DOI: 10.1109/embc.2014.6944070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In this study, we have investigated how the asymmetry of beat-to-beat foetal heart rate variability (fHRV) changes during development after 35 weeks and before 32 weeks of gestation. Noninvasive foetal electrocardiogram (fECG) signals from 78 pregnant women at the gestational age from 16 to 41 weeks with normal single pregnancies were analysed. Heart rate asymmetry (HRA) index that measures time asymmetry of RR interval time-series signal was used to understand the dynamics of fHRV. Results indicate that foetal HRA measured by Guzik's Index (GI) and Porta's Index (PI) changes after 35 weeks gestation compared to foetus before 32 weeks of gestation. It might be due to significant amount of maturation of the autonomic nervous system done after 35 and could potentially help identify the pathological autonomic nervous system development.
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Sonanini A, Stingl K, Preissl H, Brändle J, Hoopmann M, Kagan O, Wallwiener D, Abele H, Kiefer-Schmidt I. Fetal behavioral states are stable over daytime - evidence by longitudinal and cross-sectional fetal biomagnetic recordings. J Perinat Med 2014; 42:307-14. [PMID: 24225124 DOI: 10.1515/jpm-2013-0180] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Accepted: 10/09/2013] [Indexed: 11/15/2022]
Abstract
AIMS Fetal behavioral states can be distinguished by biomagnetic recordings. We performed a longitudinal and a cross-sectional study to address the question whether the distribution of fetal behavioral states changes during the daytime. METHODS For the longitudinal study, 32 magnetocardiographic recordings were performed on a singleton pregnancy on a weekly basis. On each examination day, two recordings were performed at different times between 25 and 40 weeks of gestation. For the cross-sectional study, fetal magnetocardiograms (fMCG) were recorded in a group of 32 singleton pregnancies matched for gestational age and daytime to the longitudinal study. The recordings were separated into two gestational age groups (less and more than 32 weeks). Fetal behavioral states were extracted from actocardiograms generated from MCG. RESULTS No significant differences in fetal behavioral state distribution were found between morning and afternoon recordings in either the longitudinal or the cross-sectional study. CONCLUSION This is the first magnetographic approach to show that daytime does not influence the distribution of fetal behavioral states in standardized recordings of 30 min length. This result implies that fetal magnetography recordings at normal daytimes can be combined without a bias and future recordings can be conducted independently of daytime as long as the varying behavioral states are generally taken into account during analysis.
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Kwon JY, Park IY, Lim J, Shin JC. Changes in spectral power of fetal heart rate variability in small-for-gestational-age fetuses are associated with fetal sex. Early Hum Dev 2014; 90:9-13. [PMID: 24332839 DOI: 10.1016/j.earlhumdev.2013.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Revised: 11/06/2013] [Accepted: 11/13/2013] [Indexed: 10/25/2022]
Abstract
BACKGROUND Little is known about the influences of fetal weight and sex on spectral analysis of fetal heart rate (FHR) variability. AIM The study aims to assess whether there are differences in spectral power of FHR variability according to fetal weight and sex during labor. STUDY DESIGN Case-control study. A total of 414 singleton term deliveries without fetal acidemia were divided into small-for-gestational-age (SGA) (n=29) and non-SGA (n=385) groups. Analyses were performed separately according to fetal sex. SUBJECTS FHR recordings obtained with cardiotocography during the last 2h of labor preceding delivery. OUTCOME MEASURES Our outcome measures include spectral power of FHR variability. RESULTS For the male group, SGA fetuses had significantly lower values for low, movement, high, and total frequencies of spectral power compared with non-SGA fetuses (all P<0.005). Normalized low frequency (LFn) was significantly higher, and normalized high frequency (HFn) was significantly lower in SGA fetuses compared with non-SGA fetuses (all P<0.005). In contrast, for the female group, there were no significant differences in any of the indices of spectral power between the SGA and non-SGA fetuses. In addition, SGA males had significantly higher LFn spectral power and lower HFn spectral power compared to SGA females (P=0.016, and 0.041, respectively). CONCLUSIONS SGA males have decreased spectral power of FHR variability compared with non-SGA males during labor. However, there are no differences between SGA and non-SGA female fetuses. It is important in the clinical setting to take fetal weight and sex into account during FHR monitoring using spectral analysis.
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Affiliation(s)
- Ji Young Kwon
- Department of Obstetrics and Gynecology, The Catholic University of Korea, Seoul, Republic of Korea
| | - In Yang Park
- Department of Obstetrics and Gynecology, The Catholic University of Korea, Seoul, Republic of Korea; Catholic Congenital Disease Center, The Catholic University of Korea, Seoul, Republic of Korea.
| | - Jongil Lim
- Department of Obstetrics and Gynecology, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jong Chul Shin
- Department of Obstetrics and Gynecology, The Catholic University of Korea, Seoul, Republic of Korea; Catholic Congenital Disease Center, The Catholic University of Korea, Seoul, Republic of Korea
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van Laar JOEH, Warmerdam GJJ, Verdurmen KMJ, Vullings R, Peters CHL, Houterman S, Wijn PFF, Andriessen P, van Pul C, Guid Oei S. Fetal heart rate variability during pregnancy, obtained from non-invasive electrocardiogram recordings. Acta Obstet Gynecol Scand 2013; 93:93-101. [PMID: 24134552 DOI: 10.1111/aogs.12286] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 10/12/2013] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Non-invasive spectral analysis of fetal heart rate variability is a promising new field of fetal monitoring. To validate this method properly, we studied the relationship between gestational age and the influence of fetal rest-activity state on spectral estimates of fetal heart rate variability. DESIGN Prospective longitudinal study. SETTING Tertiary care teaching hospital. POPULATION Forty healthy women with an uneventful singleton pregnancy. METHODS Non-invasive fetal electrocardiogram measurements via the maternal abdomen were performed at regular intervals between 14 and 40 weeks of gestation and processed to detect beat-to-beat fetal heart rate. Simultaneous ultrasound recordings were performed to assess fetal rest-activity state. MAIN OUTCOME MEASURES Absolute and normalized power of fetal heart rate variability in the low (0.04-0.15 Hz) and high (0.4-1.5 Hz) frequency band were obtained, using Fourier Transform. RESULTS 14% of all measurements and 3% of the total amount of abdominal data (330 segments) was usable for spectral analysis. During 21-30 weeks of gestation, a significant increase in absolute low and high frequency power was observed. During the active state near term, absolute and normalized low frequency power were significantly higher and normalized high frequency power was significantly lower compared with the quiet state. CONCLUSIONS The observed increase in absolute spectral estimates in preterm fetuses was probably due to increased sympathetic and parasympathetic modulation and might be a sign of autonomic development. Further improvements in signal processing are needed before this new method of fetal monitoring can be introduced in clinical practice.
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Affiliation(s)
- Judith O E H van Laar
- Department of Obstetrics and Gynecology, Máxima Medical Centre, Veldhoven, the Netherlands
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Van Leeuwen P, Cysarz D, Edelhäuser F, Grönemeyer D. Heart rate variability in the individual fetus. Auton Neurosci 2013; 178:24-8. [DOI: 10.1016/j.autneu.2013.01.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 12/13/2012] [Accepted: 01/04/2013] [Indexed: 10/27/2022]
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Hoyer D, Tetschke F, Jaekel S, Nowack S, Witte OW, Schleußner E, Schneider U. Fetal functional brain age assessed from universal developmental indices obtained from neuro-vegetative activity patterns. PLoS One 2013; 8:e74431. [PMID: 24058564 PMCID: PMC3776847 DOI: 10.1371/journal.pone.0074431] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 08/01/2013] [Indexed: 11/18/2022] Open
Abstract
Fetal brain development involves the development of the neuro-vegetative (autonomic) control that is mediated by the autonomic nervous system (ANS). Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS) based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4–40.3 weeks of gestation) preclassified in quiet sleep (n = 113, 63 females) and active sleep (n = 286, 145 females) state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5). The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R2 of training and validation set) of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications). We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA dependent fABAS values found in active sleep may reflect alterations in the universal developmental indices, namely fluctuation amplitude, complexity, and pattern formation that constitute fABAS.
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Affiliation(s)
- Dirk Hoyer
- Jena University Hospital, Biomagnetic Center, Hans Berger Department of Neurology, Jena, Germany
- * E-mail:
| | - Florian Tetschke
- Jena University Hospital, Biomagnetic Center, Hans Berger Department of Neurology, Jena, Germany
| | - Susan Jaekel
- Jena University Hospital, Department of Obstetrics, Jena, Germany
| | - Samuel Nowack
- Jena University Hospital, Biomagnetic Center, Hans Berger Department of Neurology, Jena, Germany
- Jena University Hospital, Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena, Germany
| | - Otto W. Witte
- Jena University Hospital, Biomagnetic Center, Hans Berger Department of Neurology, Jena, Germany
| | | | - Uwe Schneider
- Jena University Hospital, Department of Obstetrics, Jena, Germany
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Moraes ER, Murta LO, Baffa O, Wakai RT, Comani S. Linear and nonlinear measures of fetal heart rate patterns evaluated on very short fetal magnetocardiograms. Physiol Meas 2012; 33:1563-83. [PMID: 22945491 DOI: 10.1088/0967-3334/33/10/1563] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We analyzed the effectiveness of linear short- and long-term variability time domain parameters, an index of sympatho-vagal balance (SDNN/RMSSD) and entropy in differentiating fetal heart rate patterns (fHRPs) on the fetal heart rate (fHR) series of 5, 3 and 2 min duration reconstructed from 46 fetal magnetocardiograms. Gestational age (GA) varied from 21 to 38 weeks. FHRPs were classified based on the fHR standard deviation. In sleep states, we observed that vagal influence increased with GA, and entropy significantly increased (decreased) with GA (SDNN/RMSSD), demonstrating that a prevalence of vagal activity with autonomous nervous system maturation may be associated with increased sleep state complexity. In active wakefulness, we observed a significant negative (positive) correlation of short-term (long-term) variability parameters with SDNN/RMSSD. ANOVA statistics demonstrated that long-term irregularity and standard deviation of normal-to-normal beat intervals (SDNN) best differentiated among fHRPs. Our results confirm that short- and long-term variability parameters are useful to differentiate between quiet and active states, and that entropy improves the characterization of sleep states. All measures differentiated fHRPs more effectively on very short HR series, as a result of the fMCG high temporal resolution and of the intrinsic timescales of the events that originate the different fHRPs.
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Affiliation(s)
- Eder Rezende Moraes
- Departmento de Fisica e Matemática, FFCLRP-Universidade de São Paulo. Av. Bandeirantes, 3900, CEP 14040-901, Ribeirão Preto-SP, Brazil
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Hoyer D, Nowack S, Bauer S, Tetschke F, Ludwig S, Moraru L, Rudoph A, Wallwitz U, Jaenicke F, Haueisen J, Schleussner E, Schneider U. Fetal development assessed by heart rate patterns--time scales of complex autonomic control. Comput Biol Med 2011; 42:335-41. [PMID: 21621201 DOI: 10.1016/j.compbiomed.2011.05.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 03/22/2011] [Accepted: 05/02/2011] [Indexed: 11/24/2022]
Abstract
The increasing functional integrity of the organism during fetal maturation is connected with increasing complex internal coordination. We hypothesize that time scales of complexity and dynamics of heart rate patterns reflect the increasing inter-dependencies within the fetal organism during its prenatal development. We investigated multi-scale complexity, time irreversibility and fractal scaling from 73 fetal magnetocardiographic 30min recordings over the third trimester. We found different scale dependent complexity changes, increasing medium scale time irreversibility, and increasing long scale fractal correlations (all changes p<0.05). The results confirm the importance of time scales to be considered in fetal heart rate based developmental indices.
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Affiliation(s)
- Dirk Hoyer
- University Hospital, Biomagnetic Center, Hans Berger Clinic for Neurology, Friedrich Schiller University of Jena, Germany.
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