Phenotypic screening for heart rate variability in the mouse

2000 ◽  
Vol 279 (2) ◽  
pp. H733-H740 ◽  
Author(s):  
Josef Gehrmann ◽  
Peter E. Hammer ◽  
Colin T. Maguire ◽  
Hiroko Wakimoto ◽  
John K. Triedman ◽  
...  
Keyword(s):  
Heart Rate ◽  
Molecular Mechanisms ◽  
Parasympathetic Nervous System ◽  
Low Frequency ◽  
Gene Mutations ◽  
Frequency Component ◽  
High Frequency Component ◽  
Mouse Strains ◽  
Phenotypic Screening ◽  
Sensitivity Testing

We developed a technology for heart rate (HR) variability (HRV) analysis in the mouse for characterization of HR dynamics, modulated by vagal and sympathetic activity. The mouse is the principal animal model for studying biological processes. Mouse strains are now available harboring gene mutations providing fundamental insights into molecular mechanisms underlying cardiac electrical diseases. Future progress depends on enhanced understanding of these fundamental mechanisms and the implementation of methods for the functional analysis of mouse cardiovascular physiology. By telemetric techniques, standard time and frequency-domain measures of HRV were computed with and without autonomic blockade, and baroreflex sensitivity testing was performed. HR modulation in the high-frequency component is predominantly mediated by the parasympathetic nervous system, whereas the low-frequency component is under the influence of both the parasympathetic and sympathetic systems. The presented technology and protocol allow for assessment of autonomic regulation of the murine HR. Phenotypic screening for HR regulation in mice will further enhance the value of the mouse as a model of heritable electrophysiological human disease.

scholarly journals Heart Rate Variability Duration: Expanding the Ability of Wearable Technology to Improve Outpatient Monitoring?

2021 ◽  
Vol 12 ◽  
Author(s):  
David C. Sheridan ◽  
Karyssa N. Domingo ◽  
Ryan Dehart ◽  
Steven D. Baker
Keyword(s):  
Mental Health ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Time Windows ◽  
Low Frequency ◽  
Frequency Component ◽  
Wearable Technology ◽  
Mental Health Research ◽  
High Frequency Component ◽  
Frequency Domains

Heart rate variability (HRV) evaluates beat-to-beat interval (BBI) differences and is a suggested marker of the autonomic nervous system with diagnostic/monitoring capabilities in mental health; especially parasympathetic measures. The standard duration for short-term HRV analysis ranges from 24 h down to 5-min. However, wearable technology, mainly wrist devices, have large amounts of motion at times resulting in need for shorter duration of monitoring. The objective of this study was to evaluate the correlation between 1 and 5 min segments of continuous HRV data collected simultaneously on the same patient. Subjects wore a patch electrocardiograph (Cardea Solo, Inc.) over a 1–7 day period. For every consecutive hour the patch was worn, we selected a 5-min, artifact-free electrocardiogram segment. HRV metric calculation was performed to the entire 5-min segment and the first 1-min from this same 5-min segment. There were 492 h of electrocardiogram data collected allowing calculation of 492 5 min and 1 min segments. 1 min segments of data showed good correlation to 5 min segments in both time and frequency domains: root mean square of successive difference (RMSSD) (R = 0.92), high frequency component (HF) (R = 0.90), low frequency component (LF) (R = 0.71), and standard deviation of NN intervals (SDNN) (R = 0.63). Mental health research focused on parasympathetic HRV metrics, HF and RMSSD, may be accomplished through smaller time windows of recording, making wearable technology possible for monitoring.

scholarly journals Changes in Heart Rate Variability of Depressed Patients after Electroconvulsive Therapy

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Erica B. Royster ◽  
Lisa M. Trimble ◽  
George Cotsonis ◽  
Brian Schmotzer ◽  
Amita Manatunga ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Depressive Symptoms ◽  
Electroconvulsive Therapy ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Acute Changes ◽  
The Impact

Objective. As few, small studies have examined the impact of electroconvulsive therapy (ECT) upon the heart rate variability of patients with major depressive disorder (MDD), we sought to confirm whether ECT-associated improvement in depressive symptoms would be associated with increases in HRV linear and nonlinear parameters. Methods. After providing consent, depressed study participants (n=21) completed the Beck Depression Index (BDI), and 15-minute Holter monitor recordings, prior to their 1st and 6th ECT treatments. Holter recordings were analyzed for certain HRV indices: root mean square of successive differences (RMSSD), low-frequency component (LF)/high-frequency component (HF) and short-(SD1) versus long-term (SD2) HRV ratios. Results. There were no significant differences in the HRV indices of RMSDD, LF/HF, and SD1/SD2 between the patients who responded, and those who did not, to ECT. Conclusion. In the short term, there appear to be no significant improvement in HRV in ECT-treated patients whose depressive symptoms respond versus those who do not. Future studies will reveal whether diminished depressive symptoms with ECT are reliably associated with improved sympathetic/parasympathetic balance over the long-term, and whether acute changes in sympathetic/parasympathetic balance predict improved mental- and cardiac-related outcomes.

scholarly journals Stress Recovery Effects of High- and Low-Frequency Amplified Music on Heart Rate Variability

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Yoshie Nakajima ◽  
Naofumi Tanaka ◽  
Tatsuya Mima ◽  
Shin-Ichi Izumi
Keyword(s):  
Heart Rate ◽  
White Noise ◽  
High Frequency ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Stress Recovery ◽  
Recovery Ratio ◽  
Autonomic Responses ◽  
Frequency Components

Sounds can induce autonomic responses in listeners. However, the modulatory effect of specific frequency components of music is not fully understood. Here, we examined the role of the frequency component of music on autonomic responses. Specifically, we presented music that had been amplified in the high- or low-frequency domains. Twelve healthy women listened to white noise, a stress-inducing noise, and then one of three versions of a piece of music: original, low-, or high-frequency amplified. To measure autonomic response, we calculated the high-frequency normalized unit (HFnu), low-frequency normalized unit, and the LF/HF ratio from the heart rate using electrocardiography. We defined the stress recovery ratio as the value obtained after participants listened to music following scratching noise, normalized by the value obtained after participants listened to white noise after the stress noise, in terms of the HFnu, low-frequency normalized unit, LF/HF ratio, and heart rate. Results indicated that high-frequency amplified music had the highest HFnu of the three versions. The stress recovery ratio of HFnu under the high-frequency amplified stimulus was significantly larger than that under the low-frequency stimulus. Our results suggest that the high-frequency component of music plays a greater role in stress relief than low-frequency components.

scholarly journals Assessment of autonomic function by long-term heart rate variability: beyond the classical framework of LF and HF measurements

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Junichiro Hayano ◽  
Emi Yuda
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Autonomic Function ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Short Term ◽  
Heart Rate Turbulence ◽  
Free Running

AbstractIn the assessment of autonomic function by heart rate variability (HRV), the framework that the power of high-frequency component or its surrogate indices reflects parasympathetic activity, while the power of low-frequency component or LF/HF reflects sympathetic activity has been used as the theoretical basis for the interpretation of HRV. Although this classical framework has contributed greatly to the widespread use of HRV for the assessment of autonomic function, it was obtained from studies of short-term HRV (typically 5‑10 min) under tightly controlled conditions. If it is applied to long-term HRV (typically 24 h) under free-running conditions in daily life, erroneous conclusions could be drawn. Also, long-term HRV could contain untapped useful information that is not revealed in the classical framework. In this review, we discuss the limitations of the classical framework and present studies that extracted autonomic function indicators and other useful biomedical information from long-term HRV using novel approaches beyond the classical framework. Those methods include non-Gaussianity index, HRV sleep index, heart rate turbulence, and the frequency and amplitude of cyclic variation of heart rate.

Yoga-Based Guided Relaxation Reduces Sympathetic Activity Judged from Baseline Levels

2002 ◽  
Vol 90 (2) ◽  
pp. 487-494 ◽  
Author(s):  
R. P. Vempati ◽  
Shirley Telles
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Sympathetic Activity ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Before And After ◽  
Baseline Levels ◽  
Guided Relaxation ◽  
Heart Rate Variability Spectrum

35 male volunteers whose ages ranged from 20 to 46 years were studied in two sessions of yoga-based guided relaxation and supine rest. Assessments of autonomic variables were made for 15 subjects, before, during, and after the practices, whereas oxygen consumption and breath volume were recorded for 25 subjects before and after both types of relaxation. A significant decrease in oxygen consumption and increase in breath volume were recorded after guided relaxation (paired t test). There were comparable reductions in heart rate and skin conductance during both types of relaxation. During guided relaxation the power of the low frequency component of the heart-rate variability spectrum reduced, whereas the power of the high frequency component increased, suggesting reduced sympathetic activity. Also, subjects with a baseline ratio of LF/HF >0.5 showed a significant decrease in the ratio after guided relaxation, while subjects with a ratio ≤0.5 at baseline showed no such change. The results suggest that sympathetic activity decreased after guided relaxation based on yoga, depending on the baseline levels.

Impact of acute hypoxia on heart rate and blood pressure variability in conscious dogs

2000 ◽  
Vol 279 (5) ◽  
pp. H2344-H2349 ◽  
Author(s):  
Fumihiko Yasuma ◽  
Jun-Ichiro Hayano
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Arterial Pressure ◽  
Minute Ventilation ◽  
Low Frequency ◽  
Frequency Component ◽  
Conscious Dogs ◽  
High Frequency Component ◽  
Progressive Hypoxia ◽  
Cardiovascular Variables

To examine whether the impacts of hypoxia on autonomic regulations involve the phasic modulations as well as tonic controls of cardiovascular variables, heart rate, blood pressure, and their variability during isocapnic progressive hypoxia were analyzed in trained conscious dogs prepared with a permanent tracheostomy and an implanted blood pressure telemetry unit. Data were obtained at baseline and when minute ventilation (V˙i) first reached 10 (V˙i10), 15 (V˙i15), and 20 (V˙i20) l/min during hypoxia. Time-dependent changes in the amplitudes of the high-frequency component of the R-R interval (RRIHF) and the low-frequency component of mean arterial pressure (MAPLF) were analyzed by complex demodulation. In a total of 47 progressive hypoxic runs in three dogs, RRIHF decreased atV˙i15 and V˙i20 and MAPLF increased at V˙i10 and V˙i15 but not atV˙i20, whereas heart rate and arterial pressure increased progressively with advancing hypoxia. We conclude that the autonomic responses to isocapnic progressive hypoxia involve tonic controls and phasic modulations of cardiovascular variables; the latter may be characterized by a progressive reduction in respiratory vagal modulation of heart rate and a transient augmentation in low-frequency sympathetic modulation of blood pressure.

Effects of 2-Hz and 100-Hz Electroacupuncture Stimulation on Respiratory Function and Heart Rate Variability: A Randomized Crossover Study

2021 ◽  
Author(s):  
Kazufumi Takahashi ◽  
Xiaoming Wang ◽  
Daiyu Shginohara ◽  
Kenji Imai
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
High Frequency ◽  
Respiratory Function ◽  
Low Frequency ◽  
Frequency Component ◽  
Autonomic Nerve ◽  
High Frequency Component ◽  
Respiratory Function Test ◽  
Function Test

Background: Bronchial contraction and dilation is thought to be caused by non-adrenergic non-cholinergic nerves. Objective: To investigate the effects of low-frequency (1-5 Hz) and high frequency (50-100 Hz) electric acupuncture (EA) stimulation on bronchial dilation. Design: Prospective, single-center study. Setting: Teikyo Heisei University Subjects: Seventeen healthy male adults Randomization: We randomly assigned subjects to 2-Hz EA and 100-Hz EA groups in a crossover trial. The washout period was 2 weeks. Intervention: Both groups underwent a respiratory function test, followed by a 5-minute rest, followed a 5-minute rest or EA stimulation, followed by a 5- min rest. Heart rate variability was measured at rest, followed by another respiratory function test. Acupuncture was delivered near the cervical ganglia at the level of the sixth cervical vertebra on the left side. EA stimuli were set to 2-Hz or 100-Hz, and stimulation intensity was set to a level where no pain was felt. Main outcome measures: Spirometry (forced vital capacity, forced expiratory volume in 1 s, and maximum respiratory flow), autonomic nerve activity (low-frequency component, high-frequency component, and their ratio), and heart rate variability. Results: Heart rate variability analysis showed significant differences in heart rate between the 2-Hz EA and 100-Hz EA groups. The 2-Hz EA group showed a significant increase in HF. Conclusions: 2-Hz EA stimulation resulted in decreased heart rate and increased HF during stimulation. This may be more effective for regulation of the autonomic nerves of the cardiopulmonary system than 100-Hz EA stimulation. Future studies are required to confirm our findings.

scholarly journals DYNAMICS OF HEART RATE VARIABILITY UNDER THE INFLUENCE OF COURSE YOGA BREATHING EXERCISES ON HEALTHY YOUNG PEOPLE

2019 ◽  
Vol 72 (4) ◽  
pp. 613-616 ◽  
Author(s):  
Nataliia I. Sheiko ◽  
Volodymyr P. Feketa
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
High Frequency ◽  
Cardiac Rhythm ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Regulatory Activity ◽  
Biological Feedback ◽  
Very Low Frequency

Introduction: Heart rate variability is a highly informative non-invasive method of research not only for the functional state of the cardiovascular system and also for the integrative regulatory activity of the autonomic nervous system. The positive effect of diaphragmatic breathing is positive in the mode of biological feedback using portable devices, but there is little evidence of the use of yoga breathing gymnastics in order to influence the heart rate variability. The aim: To compare the possibilities of using courses of breathing gymnastics of yogis and diaphragmatic breathing sessions in the mode of biological feedback using a portable device. Materials and methods: The study involved 70 practically healthy foreigners, who were divided into 2 groups of 35 people. Participants of the 1st group daily engage in respiratory exercises pranayama for 15 minutes in 1 month. Participants in the 2nd group used the MyCalmBeat portable device. Heart rate variability was registered by using the computer diagnostic complex “CardioLab” (“KhAI-Medika”, Ukraine). Results: In both groups there was similar dynamics of heart rate variability indices, but its severity was different. The common integral effect was a significant growth of heart rate variability both according to statistical and spectral indicators – total power increased, as well as high-frequency component. The power of the very-low frequency waves has probably decreased only in the group with the device. In the percentage structure of the cardiac rhythm spectrum, the specific weight of very-low frequency component and the percentage of high-frequency component increased. Conclusions: Respiratory gymnastics yoga for 15 minutes daily contributes to the growth of heart rate variability through the suppression of the central link (very-low frequency component) of regulation of cardiac rhythm and increased activity of parasympathetic influences (high-frequency component), as well as the redistribution of regulatory activity of the central nervous system between the central and peripheral links of regulation of the cardiac rhythm in favor of the latter.

scholarly journals Heart Rate Variability in HIV Patients, Diabetics, and Controls: The AGATAA Study

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Isabela M. Benseñor ◽  
Margareth Eira ◽  
Egídio Lima Dorea ◽  
Eduardo M. Dantas ◽  
José Geraldo Mill ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Highly Active Antiretroviral Therapy ◽  
Autonomic Function ◽  
Low Frequency ◽  
Frequency Component ◽  
High Frequency Component ◽  
Cardiac Autonomic Function ◽  
Hiv Patients ◽  
Highly Active

HIV infection can affect cardiac autonomic function. We aimed to compare heart rate variability in 29 HIV-infected patients using highly active antiretroviral therapy (HAART), 28 naïve-treatment HIV patients, and diabetics with controls. There was no difference in time index parameters among groups. The normalized power of the low-frequency component (LF) in naïve patients of 39.9 (interquartile interval (IQ), 28.5–65.7) and diabetics of 42.9 (IQ, 14.5–57.7) were decreased compared with controls (67.5, IQ, 37.9–75.4). The normalized power of the high-frequency component (HF) in naïves of 49.7 (IQ, 30.4–64.8), and diabetics of 53.1 (IQ, 34.5–72.2) were increased compared with controls (27.0, IQ, 19.0–57.3). Naïve and diabetics also presented with lower LF/HF ratios (0.8 (IQ, 0.6–2.3), and 0.9 (IQ, 0.3–1.4),) compared with controls (2.3 (IQ, 0.8–3.3)). We can speculate that HAART improves autonomic imbalance in frequency domain indices because there was no difference between the HAART group and controls.

scholarly journals Impaired vagal activity to meal in patients with functional dyspepsia and delayed gastric emptying

2017 ◽  
Vol 46 (2) ◽  
pp. 792-801 ◽  
Author(s):  
W-J Guo ◽  
S-K Yao ◽  
Y-L Zhang ◽  
S-Y Du ◽  
H-F Wang ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
Gastric Emptying ◽  
Functional Dyspepsia ◽  
Delayed Gastric Emptying ◽  
Low Frequency ◽  
Treatment Method ◽  
Frequency Component ◽  
High Frequency Component ◽  
Vagal Activity ◽  
Nervous Function

Objective This study was performed to investigate impaired vagal activity to meal in patients with functional dyspepsia (FD) with delayed gastric emptying (GE). Methods Eighty-five patients were studied. GE parameters, including those in the overall and proximal stomach, were measured by GE functional tests at the Department of Nuclear Medicine. Autonomic nervous function was tested by spectral analysis of heart rate variability (HRV). The vagal activity and sympathetic activity were analyzed by recording the power in the high-frequency component (HF), low-frequency component (LF), and LF/HF ratio. Results Overall and proximal GE were delayed in 47.2% and 50.9% of the patients, respectively. Spectral analysis of HRV showed that the HF in patients with delayed proximal GE was significantly lower and that the LF/HF ratio was significantly higher than those in patients with normal proximal GE after a meal. Conclusion Delayed proximal GE might be caused by disrupted sympathovagal balance as a result of decreased vagal activity after a meal. Improvement in vagal activity may constitute an effective treatment method for patients with FD.

Sign in / Sign up

Export Citation Format

Share Document