Entertainment Capture through Heart Rate Activity in Physical Interactive Playgrounds

DEFF Research Database (Denmark)

Yannakakis, Georgios; Hallam, John; Lund, Henrik Hautop

2008-01-01

children’s physiological signals, an estimator of the degree to which games provided by the playground engage the players. For this purpose children’s heart rate (HR) signals, and their expressed preferences of how much “fun” particular game variants are, are obtained from experiments using games...... that predict reported entertainment preferences given HR features. These models are expressed as artificial neural networks and are demonstrated and evaluated on two Playware games and two control tasks requiring physical activity. The best network is able to correctly match expressed preferences in 64...

Heart Rate Variability - A Historical Perspective

Directory of Open Access Journals (Sweden)

George E Billman

2011-11-01

Full Text Available Heart rate variability (HRV, the beat-to-beat variation in either heart rate or the duration of the R-R interval – the heart period, has become a popular clinical and investigational tool. The temporal fluctuations in heart rate exhibit a marked synchrony with respiration (increasing during inspiration and decreasing during expiration – the so called respiratory sinus arrhythmia, RSA and are widely believed to reflect changes in cardiac autonomic regulation. Although the exact contributions of the parasympathetic and the sympathetic divisions of the autonomic nervous system to this variability are controversial and remain the subject of active investigation and debate, a number of time and frequency domain techniques have been developed to provide insight into cardiac autonomic regulation in both health and disease. It is the purpose of this essay to provide an historical overview of the evolution in the concept of heart rate variability. Briefly, pulse rate was first measured by ancient Greek physicians and scientists. However, it was not until the invention of the Physician’s Pulse Watch (a watch with a second hand that could be stopped in 1707 that changes in pulse rate could be accurately assessed. The Rev. Stephen Hales (1733 was the first to note that pulse varied with respiration and in 1847 Carl Ludwig was the first to record RSA. With the measurement of the ECG (1895 and advent of digital signal processing techniques in the 1960’s, investigation of HRV and its relationship to health and disease has exploded. This essay will conclude with a brief description of time domain, frequency domain, and non-linear dynamic analysis techniques (and their limitations that are commonly used to measure heart rate variability.

The Effect of Heart Rate on the Heart Rate Variability Response to Autonomic Interventions

Directory of Open Access Journals (Sweden)

George E Billman

2013-08-01

Full Text Available Heart rate variability (HRV, the beat-to-beat variation in either heart rate (HR or heart period (R-R interval, has become a popular clinical and investigational tool to quantify cardiac autonomic regulation. However, it is not widely appreciated that, due to the inverse curvilinear relationship between HR and R-R interval, HR per se can profoundly influence HRV. It is, therefore, critical to correct HRV for the prevailing HR particularly, as HR changes in response to autonomic neural activation or inhibition. The present study evaluated the effects of HR on the HRV response to autonomic interventions that either increased (submaximal exercise, n = 25 or baroreceptor reflex activation, n = 20 or reduced (pharmacological blockade: β-adrenergic receptor, muscarinic receptor antagonists alone and in combination, n = 25, or bilateral cervical vagotomy, n = 9 autonomic neural activity in a canine model. Both total (RR interval standard deviation, RRSD and the high frequency variability (HF, 0.2 to 1.04 Hz were determined before and in response to an autonomic intervention. All interventions that reduced or abolished cardiac parasympathetic regulation provoked large reductions in HRV even after HR correction [division by mean RRsec or (mean RRsec2 for RRSD and HF, respectively] while interventions that reduced HR yielded mixed results. β-adrenergic receptor blockade reduced HRV (RRSD but not HF while both RRSD and HF increased in response to increases in arterial blood (baroreceptor reflex activation even after HR correction. These data suggest that the physiological basis for HRV is revealed after correction for prevailing HR and, further, that cardiac parasympathetic activity is responsible for a major portion of the HRV in the dog.

Behavioral correlates of heart rates of free-living Greater White-fronted Geese

Science.gov (United States)

Ely, Craig R.; Ward, D.H.; Bollinger, K.S.

1999-01-01

We simultaneously monitored the heart rate and behavior of nine free-living Greater White-fronted Geese (Anser albifrons) on their wintering grounds in northern California. Heart rates of wild geese were monitored via abdominally-implanted radio transmitters with electrodes that received electrical impulses of the heart and emitted a radio signal with each ventricular contraction. Post-operative birds appeared to behave normally, readily rejoining flocks and flying up to 15 km daily from night-time roost sites to feed in surrounding agricultural fields. Heart rates varied significantly among individuals and among behaviors, and ranged from less than 100 beats per minute (BPM) during resting, to over 400 BPM during flight. Heart rates varied from 80 to 140 BPM during non-strenuous activities such as walking, feeding, and maintenance activities, to about 180 BPM when birds became alert, and over 400 BPM when birds were startled, even if they did not take flight. Postflight heart rate recovery time averaged postures, as heart rates were context-dependent, and were highest in initial encounters among individuals. Instantaneous measures of physiological parameters, such as heart rate, are often better indicators of the degree of response to external stimuli than visual observations and can be used to improve estimates of energy expenditure based solely on activity data.

Validation of Heart Rate Monitor Polar RS800 for Heart Rate Variability Analysis During Exercise.

Science.gov (United States)

Hernando, David; Garatachea, Nuria; Almeida, Rute; Casajús, Jose A; Bailón, Raquel

2018-03-01

Hernando, D, Garatachea, N, Almeida, R, Casajús, JA, and Bailón, R. Validation of heart rate monitor Polar RS800 for heart rate variability analysis during exercise. J Strength Cond Res 32(3): 716-725, 2018-Heart rate variability (HRV) analysis during exercise is an interesting noninvasive tool to measure the cardiovascular response to the stress of exercise. Wearable heart rate monitors are a comfortable option to measure interbeat (RR) intervals while doing physical activities. It is necessary to evaluate the agreement between HRV parameters derived from the RR series recorded by wearable devices and those derived from an electrocardiogram (ECG) during dynamic exercise of low to high intensity. Twenty-three male volunteers performed an exercise stress test on a cycle ergometer. Subjects wore a Polar RS800 device, whereas ECG was also recorded simultaneously to extract the reference RR intervals. A time-frequency spectral analysis was performed to extract the instantaneous mean heart rate (HRM), and the power of low-frequency (PLF) and high-frequency (PHF) components, the latter centered on the respiratory frequency. Analysis was done in intervals of different exercise intensity based on oxygen consumption. Linear correlation, reliability, and agreement were computed in each interval. The agreement between the RR series obtained from the Polar device and from the ECG is high throughout the whole test although the shorter the RR is, the more differences there are. Both methods are interchangeable when analyzing HRV at rest. At high exercise intensity, HRM and PLF still presented a high correlation (ρ > 0.8) and excellent reliability and agreement indices (above 0.9). However, the PHF measurements from the Polar showed reliability and agreement coefficients around 0.5 or lower when the level of the exercise increases (for levels of O2 above 60%).

Heart rate biofeedback fails to enhance children's ability to identify time spent in moderate to vigorous physical activity.

Science.gov (United States)

Conley, Marguerite M; Gastin, Paul B; Brown, Helen; Shaw, Christine

2011-03-01

Physical activity recommendations for children in several countries advise that all young people should accumulate at least 60 min of moderate to vigorous physical activity every day. Perceiving physical activity intensity, however, can be a difficult task for children and it is not clear whether children can identify their levels of moderate to vigorous physical activity in accordance with the recommended guidelines. This study aimed to (1) explore whether children can identify time spent in moderate to vigorous physical activity; and (2) investigate whether heart rate biofeedback would improve children's ability to estimate time spent in moderate to vigorous physical activity. Thirty seven children (15 boys and 22 girls, mean age 12.6 years) wore data recording Polar E600 heart rate monitors during eight physical education lessons. At the end of each lesson children's estimated time in zone was compared to their actual time in zone. During a six lesson Intervention phase, one class was assigned to a biofeedback group whilst the other class acted as the control group and received no heart rate biofeedback. Post-Intervention, students in the biofeedback group were no better than the control group at estimating time spent in zone (mean relative error of estimation biofeedback group: Pre-Intervention 41±32% to Post-Intervention 28±26%; control group: Pre-Intervention 40±39% to Post-Intervention 31±37%). Thus it seems that identifying time spent in moderate to vigorous physical activity remains a complex task for children aged 11-13 even with the help of heart rate biofeedback. Copyright © 2010 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Heart rate and heart rate variability modification in chronic insomnia patients.

Science.gov (United States)

Farina, Benedetto; Dittoni, Serena; Colicchio, Salvatore; Testani, Elisa; Losurdo, Anna; Gnoni, Valentina; Di Blasi, Chiara; Brunetti, Riccardo; Contardi, Anna; Mazza, Salvatore; Della Marca, Giacomo

2014-01-01

Chronic insomnia is highly prevalent in the general population, provoking personal distress and increased risk for psychiatric and medical disorders. Autonomic hyper-arousal could be a pathogenic mechanism of chronic primary insomnia. The aim of this study was to investigate autonomic activity in patients with chronic primary insomnia by means of heart rate variability (HRV) analysis. Eighty-five consecutive patients affected by chronic primary insomnia were enrolled (38 men and 47 women; mean age: 53.2 ± 13.6). Patients were compared with a control group composed of 55 healthy participants matched for age and gender (23 men and 32 women; mean age: 54.2 ± 13.9). Patients underwent an insomnia study protocol that included subjective sleep evaluation, psychometric measures, and home-based polysomnography with evaluation of HRV in wake before sleep, in all sleep stages, and in wake after final awakening. Patients showed modifications of heart rate and HRV parameters, consistent with increased sympathetic activity, while awake before sleep and during Stage-2 non-REM sleep. No significant differences between insomniacs and controls could be detected during slow-wave sleep, REM sleep, and post-sleep wake. These results are consistent with the hypothesis that autonomic hyper-arousal is a major pathogenic mechanism in primary insomnia, and confirm that this condition is associated with an increased cardiovascular risk.

Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice

DEFF Research Database (Denmark)

Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

2011-01-01

these observations with observations made from mice examined by wheel-running activity. The study demonstrates that VPAC2 signaling is necessary for a functional circadian clock driving locomotor activity, core body temperature, and heart rate rhythmicity, since VPAC2-deficient mice lose the rhythms in all three...... to that of wild-type mice. The use of telemetric devices to measure circadian locomotor activity, temperature, and heart rate, together with the classical determination of circadian rhythms of wheel-running activity, raises questions about how representative wheel-running activity may be of other behavioral...

Influence of heavy cigarette smoking on heart rate variability and heart rate turbulence parameters

DEFF Research Database (Denmark)

Cagirci, Goksel; Cay, Serkan; Karakurt, Ozlem

2009-01-01

BACKGROUND: Cigarette smoking increases the risk of cardiovascular events related with several mechanisms. The most suggested mechanism is increased activity of sympathetic nervous system. Heart rate variability (HRV) and heart rate turbulence (HRT) has been shown to be independent and powerful......, 69 subjects and nonsmokers 74 subjects (control group) were enrolled in this study. HRV and HRT analyses [turbulence onset (TO) and turbulence slope (TS)] were assessed from 24-hour Holter recordings. RESULTS: The values of TO were significantly higher in heavy cigarette smokers than control group...... (-1.150 +/- 4.007 vs -2.454 +/- 2.796, P = 0.025, respectively), but values of TS were not statistically different between two groups (10.352 +/- 7.670 vs 9.613 +/- 7.245, P = 0.555, respectively). Also, the number of patients who had abnormal TO was significantly higher in heavy cigarette smokers...

Power spectral analysis of heart rate in hyperthyroidism.

Science.gov (United States)

Cacciatori, V; Bellavere, F; Pezzarossa, A; Dellera, A; Gemma, M L; Thomaseth, K; Castello, R; Moghetti, P; Muggeo, M

1996-08-01

The aim of the present study was to evaluate the impact of hyperthyroidism on the cardiovascular system by separately analyzing the sympathetic and parasympathetic influences on heart rate. Heart rate variability was evaluated by autoregressive power spectral analysis. This method allows a reliable quantification of the low frequency (LF) and high frequency (HF) components of the heart rate power spectral density; these are considered to be under mainly sympathetic and pure parasympathetic control, respectively. In 10 newly diagnosed untreated hyperthyroid patients with Graves' disease, we analyzed power spectral density of heart rate cyclic variations at rest, while lying, and while standing. In addition, heart rate variations during deep breathing, lying and standing, and Valsalva's maneuver were analyzed. The results were compared to those obtained from 10 age-, sex-, and body mass index-matched control subjects. In 8 hyperthyroid patients, the same evaluation was repeated after the induction of stable euthyroidism by methimazole. Heart rate power spectral analysis showed a sharp reduction of HF components in hyperthyroid subjects compared to controls [lying, 13.3 +/- 4.1 vs. 32.0 +/- 5.6 normalized units (NU; P hyperthyroid subjects while both lying (11.3 +/- 4.5 vs. 3.5 +/- 1.1; P hyperthyroid patients than in controls (1.12 +/- 0.03 vs. 1.31 +/- 0.04; P activity and, thus, a relative hypersympathetic tone.

Quantification of fetal heart rate regularity using symbolic dynamics

Science.gov (United States)

van Leeuwen, P.; Cysarz, D.; Lange, S.; Geue, D.; Groenemeyer, D.

2007-03-01

Fetal heart rate complexity was examined on the basis of RR interval time series obtained in the second and third trimester of pregnancy. In each fetal RR interval time series, short term beat-to-beat heart rate changes were coded in 8bit binary sequences. Redundancies of the 28 different binary patterns were reduced by two different procedures. The complexity of these sequences was quantified using the approximate entropy (ApEn), resulting in discrete ApEn values which were used for classifying the sequences into 17 pattern sets. Also, the sequences were grouped into 20 pattern classes with respect to identity after rotation or inversion of the binary value. There was a specific, nonuniform distribution of the sequences in the pattern sets and this differed from the distribution found in surrogate data. In the course of gestation, the number of sequences increased in seven pattern sets, decreased in four and remained unchanged in six. Sequences that occurred less often over time, both regular and irregular, were characterized by patterns reflecting frequent beat-to-beat reversals in heart rate. They were also predominant in the surrogate data, suggesting that these patterns are associated with stochastic heart beat trains. Sequences that occurred more frequently over time were relatively rare in the surrogate data. Some of these sequences had a high degree of regularity and corresponded to prolonged heart rate accelerations or decelerations which may be associated with directed fetal activity or movement or baroreflex activity. Application of the pattern classes revealed that those sequences with a high degree of irregularity correspond to heart rate patterns resulting from complex physiological activity such as fetal breathing movements. The results suggest that the development of the autonomic nervous system and the emergence of fetal behavioral states lead to increases in not only irregular but also regular heart rate patterns. Using symbolic dynamics to

Mice lacking melanin-concentrating hormone receptor 1 demonstrate increased heart rate associated with altered autonomic activity.

Science.gov (United States)

Astrand, Annika; Bohlooly-Y, Mohammad; Larsdotter, Sara; Mahlapuu, Margit; Andersén, Harriet; Tornell, Jan; Ohlsson, Claes; Snaith, Mike; Morgan, David G A

2004-10-01

Melanin-concentrating hormone (MCH) plays an important role in energy balance. The current studies were carried out on a new line of mice lacking the rodent MCH receptor (MCHR1(-/-) mice). These mice confirmed the previously reported lean phenotype characterized by increased energy expenditure and modestly increased caloric intake. Because MCH is expressed in the lateral hypothalamic area, which also has an important role in the regulation of the autonomic nervous system, heart rate and blood pressure were measured by a telemetric method to investigate whether the increased energy expenditure in these mice might be due to altered autonomic nervous system activity. Male MCHR1(-/-) mice demonstrated a significantly increased heart rate [24-h period: wild type 495 +/- 4 vs. MCHR1(-/-) 561 +/- 8 beats/min (P dark phase: wild type 506 +/- 8 vs. MCHR1(-/-) 582 +/- 9 beats/min (P light phase: wild type 484 +/- 13 vs. MCHR1(-/-) 539 +/- 9 beats/min (P vs. MCHR1(-/-) 113 +/- 0.4 mmHg (P > 0.05)]. Locomotor activity and core body temperature were higher in the MCHR1(-/-) mice during the dark phase only and thus temporally dissociated from heart rate differences. On fasting, wild-type animals rapidly downregulated body temperature and heart rate. MCHR1(-/-) mice displayed a distinct delay in the onset of this downregulation. To investigate the mechanism underlying these differences, autonomic blockade experiments were carried out. Administration of the adrenergic antagonist metoprolol completely reversed the tachycardia seen in MCHR1(-/-) mice, suggesting an increased sympathetic tone.

Assessment of post-laparotomy pain in laboratory mice by telemetric recording of heart rate and heart rate variability

Science.gov (United States)

Arras, Margarete; Rettich, Andreas; Cinelli, Paolo; Kasermann, Hans P; Burki, Kurt

2007-01-01

Background Pain of mild to moderate grade is difficult to detect in laboratory mice because mice are prey animals that attempt to elude predators or man by hiding signs of weakness, injury or pain. In this study, we investigated the use of telemetry to identify indicators of mild-to-moderate post-laparotomy pain. Results Adult mice were subjected to laparotomy, either combined with pain treatment (carprofen or flunixin, 5 mg/kg s/c bid, for 1 day) or without pain relief. Controls received anesthesia and analgesics or vehicle only. Telemetrically measured locomotor activity was undisturbed in all animals, thus confirming that any pain experienced was of the intended mild level. No symptoms of pain were registered in any of the groups by scoring the animals' outer appearance or spontaneous and provoked behavior. In contrast, the group receiving no analgesic treatment after laparotomy demonstrated significant changes in telemetry electrocardiogram recordings: increased heart rate and decreased heart rate variability parameters pointed to sympathetic activation and pain lasting for 24 hours. In addition, core body temperature was elevated. Body weight and food intake were reduced for 3 and 2 days, respectively. Moreover, unstructured cage territory and destroyed nests appeared for 1–2 days in an increased number of animals in this group only. In controls these parameters were not affected. Conclusion In conclusion, real-time telemetric recordings of heart rate and heart rate variability were indicative of mild-to-moderate post-laparotomy pain and could define its duration in our mouse model. This level of pain cannot easily be detected by direct observation. PMID:17683523

The use of heart rate turbulence and heart rate variability in the assessment of autonomic regulation and circadian rhythm in patients with systemic lupus erythematosus without apparent heart disease.

Science.gov (United States)

Poliwczak, A R; Waszczykowska, E; Dziankowska-Bartkowiak, B; Koziróg, M; Dworniak, K

2018-03-01

Background Systemic lupus erythematosus is a progressive autoimmune disease. There are reports suggesting that patients even without overt signs of cardiovascular complications have impaired autonomic function. The aim of this study was to assess autonomic function using heart rate turbulence and heart rate variability parameters indicated in 24-hour ECG Holter monitoring. Methods Twenty-six women with systemic lupus erythematosus and 30 healthy women were included. Twenty-four hour ambulatory ECG-Holter was performed in home conditions. The basic parameters of heart rate turbulence and heart rate variability were calculated. The analyses were performed for the entire day and separately for daytime activity and night time rest. Results There were no statistically significant differences in the basic anthropometric parameters. The mean duration of disease was 11.52 ± 7.42. There was a statistically significant higher turbulence onset (To) value in patients with systemic lupus erythematosus, median To = -0.17% (minimum -1.47, maximum 3.0) versus To = -1.36% (minimum -4.53, maximum -0.41), P lupus erythematosus group than in the healthy controls, including SDANN and r-MSSD and p50NN. Concerning the morning activity and night resting periods, the results were similar as for the whole day. In the control group, higher values in morning activity were noted for parameters that characterise sympathetic activity, especially SDANN, and were significantly lower for parasympathetic parameters, including r-MSSD and p50NN, which prevailed at night. There were no statistically significant changes for systemic lupus erythematosus patients for p50NN and low and very low frequency. There was a positive correlation between disease duration and SDNN, R = 0.417; P < 0.05 and SDANN, R = 0.464; P < 0.05, a negative correlation between low/high frequency ratio and r-MSSD, R = -0.454; P < 0.05; p50NN, R = -0.435; P < 0.05 and high frequency

Heart rate variability in healthy population

International Nuclear Information System (INIS)

Alamgir, M.; Hussain, M.M.

2010-01-01

Background: Heart rate variability has been considered as an indicator of autonomic status. Little work has been done on heart rate variability in normal healthy volunteers. We aimed at evolving the reference values of heart rate variability in our healthy population. Methods: Twenty-four hour holter monitoring of 37 healthy individuals was done using Holter ECG recorder 'Life card CF' from 'Reynolds Medical'. Heart rate variability in both time and frequency domains was analysed with 'Reynolds Medical Pathfinder Digital/700'. Results: The heart rate variability in normal healthy volunteers of our population was found in time domain using standard deviation of R-R intervals (SDNN), standard deviation of average NN intervals (SDANN), and Square root of the mean squared differences of successive NN intervals (RMSSD). Variation in heart rate variability indices was observed between local and foreign volunteers and RMSSD was found significantly increased (p<0.05) in local population. Conclusions: The values of heart rate variability (RMSSD) in healthy Pakistani volunteers were found increased compared to the foreign data reflecting parasympathetic dominance in our population. (author)

[The influence of physical exercise on heart rate variability].

Science.gov (United States)

Gajek, Jacek; Zyśko, Dorota; Negrusz-Kawecka, Marta; Halawa, Bogumił

2003-03-01

Heart rate variability is controlled by the influence of autonomic nervous system, whereas one part of the system modulates the activity of the other. There is evidence of increased sympathetic activity in patients (pts) with essential hypertension. The aim of the study was to assess the persisting influence of increased sympathetic activity 30 min after moderate physical exercise on heart rate variability in patients with arterial hypertension. The study was performed in 19 patients (10 women, mean age 52.7 +/- 9.5 years and 9 men, mean age 37.7 +/- 8.8 years) with stage I (6 pts) and stage II (13 pts) arterial hypertension. All studied pts had sinus rhythm, were free of diabetes, coronary heart disease and congestive heart failure. 24-hour Holter monitoring was performed and for 30 min before the exercise test the pts stayed in supine rest. The exercise tests were performed between 10 and 11 a.m. Immediately after the exercise all pts stayed in supine position for 30 min. The heart rate variability parameters were studied using Holter monitoring system Medilog Optima Jet and were then analysed statistically. The mean energy expenditure during the exercise was 5.8 +/- 1.1 METs and the maximal heart rate was 148.1 +/- 20.3 bpm. All studied HRV parameters were significantly different in the assessed time period compared to the baseline values (p < 0.001). Significant correlation was found between the age of the studied patients and the mean RR interval, what can be considered as a hyperkinetic (hyperadrenergic) circulatory status and shorter RR interval in younger pts. Significant negative correlation between the age and SDNN parameter (r = -0.65, p < 0.001), 30 min after the exercise mirrors the prolonged adrenergic influence in older pts. The present study shows that the influence of moderate physical exercise on heart rate variability in pts with essential hypertension is extended over 30 min period after exercise and is more pronounced in older pts. The studies

Assessment of post-laparotomy pain in laboratory mice by telemetric recording of heart rate and heart rate variability

Directory of Open Access Journals (Sweden)

Kasermann Hans P

2007-08-01

Full Text Available Abstract Background Pain of mild to moderate grade is difficult to detect in laboratory mice because mice are prey animals that attempt to elude predators or man by hiding signs of weakness, injury or pain. In this study, we investigated the use of telemetry to identify indicators of mild-to-moderate post-laparotomy pain. Results Adult mice were subjected to laparotomy, either combined with pain treatment (carprofen or flunixin, 5 mg/kg s/c bid, for 1 day or without pain relief. Controls received anesthesia and analgesics or vehicle only. Telemetrically measured locomotor activity was undisturbed in all animals, thus confirming that any pain experienced was of the intended mild level. No symptoms of pain were registered in any of the groups by scoring the animals' outer appearance or spontaneous and provoked behavior. In contrast, the group receiving no analgesic treatment after laparotomy demonstrated significant changes in telemetry electrocardiogram recordings: increased heart rate and decreased heart rate variability parameters pointed to sympathetic activation and pain lasting for 24 hours. In addition, core body temperature was elevated. Body weight and food intake were reduced for 3 and 2 days, respectively. Moreover, unstructured cage territory and destroyed nests appeared for 1–2 days in an increased number of animals in this group only. In controls these parameters were not affected. Conclusion In conclusion, real-time telemetric recordings of heart rate and heart rate variability were indicative of mild-to-moderate post-laparotomy pain and could define its duration in our mouse model. This level of pain cannot easily be detected by direct observation.

Monitoring apparatus for monitoring a user's heart rate and/or heart rate variation

NARCIS (Netherlands)

2012-01-01

A monitoring apparatus (4) monitors a user's heart rate and/or heart rate variation. The apparatus includes a capacitor (22) which is positionable on or near a body part of a person, for example a person's limb, for example an arm (3), such that an electrical capacitance of the capacitor (22) is

Reduced Dietary Sodium Intake Increases Heart Rate

DEFF Research Database (Denmark)

Graudal, Niels A; Hubeck-Graudal, Thorbjørn; Jürgens, Gesche

2016-01-01

Reduced dietary sodium intake (sodium reduction) increases heart rate in some studies of animals and humans. As heart rate is independently associated with the development of heart failure and increased risk of premature death a potential increase in heart rate could be a harmful side......-effect of sodium reduction. The purpose of the present meta-analysis was to investigate the effect of sodium reduction on heart rate. Relevant studies were retrieved from an updated pool of 176 randomized controlled trials (RCTs) published in the period 1973-2014. Sixty-three of the RCTs including 72 study...... populations reported data on heart rate. In a meta-analysis of these data sodium reduction increased heart rate with 1.65 beats per minute [95% CI: 1.19, 2.11], p heart rate. This effect was independent of baseline blood pressure. In conclusion sodium reduction...

Comparative evaluation of heart rate-based monitors: Apple Watch vs Fitbit Charge HR.

Science.gov (United States)

Bai, Yang; Hibbing, Paul; Mantis, Constantine; Welk, Gregory J

2018-08-01

The purpose of this investigation was to examine the validity of energy expenditure (EE), steps, and heart rate measured with the Apple Watch 1 and Fitbit Charge HR. Thirty-nine healthy adults wore the two monitors while completing a semi-structured activity protocol consisting of 20 minutes of sedentary activity, 25 minutes of aerobic exercise, and 25 minutes of light intensity physical activity. Criterion measures were obtained from an Oxycon Mobile for EE, a pedometer for steps, and a Polar heart rate strap worn on the chest for heart rate. For estimating whole-trial EE, the mean absolute percent error (MAPE) from Fitbit Charge HR (32.9%) was more than twice that of Apple Watch 1 (15.2%). This trend was consistent for the individual conditions. Both monitors accurately assessed steps during aerobic activity (MAPE Apple : 6.2%; MAPE Fitbit : 9.4%) but overestimated steps in light physical activity. For heart rate, Fitbit Charge HR produced its smallest MAPE in sedentary behaviors (7.2%), followed by aerobic exercise (8.4%), and light activity (10.1%). The Apple Watch 1 had stronger validity than the Fitbit Charge HR for assessing overall EE and steps during aerobic exercise. The Fitbit Charge HR provided heart rate estimates that were statistically equivalent to Polar monitor.

Continuous measurement of heart rate variability following carbon ...

African Journals Online (AJOL)

Background: Previous studies of autonomic nervous system activity through analysis of heart rate variability (HRV) have demonstrated increased sympathetic activity during positive-pressure pneumoperitoneum. We employed an online, continuous method for rapid HRV analysis (MemCalc™, Tarawa, Suwa Trust, Tokyo, ...

Heart rate variability - a historical perspective.

Science.gov (United States)

Billman, George E

2011-01-01

Heart rate variability (HRV), the beat-to-beat variation in either heart rate or the duration of the R-R interval - the heart period, has become a popular clinical and investigational tool. The temporal fluctuations in heart rate exhibit a marked synchrony with respiration (increasing during inspiration and decreasing during expiration - the so called respiratory sinus arrhythmia, RSA) and are widely believed to reflect changes in cardiac autonomic regulation. Although the exact contributions of the parasympathetic and the sympathetic divisions of the autonomic nervous system to this variability are controversial and remain the subject of active investigation and debate, a number of time and frequency domain techniques have been developed to provide insight into cardiac autonomic regulation in both health and disease. It is the purpose of this essay to provide an historical overview of the evolution in the concept of HRV. Briefly, pulse rate was first measured by ancient Greek physicians and scientists. However, it was not until the invention of the "Physician's Pulse Watch" (a watch with a second hand that could be stopped) in 1707 that changes in pulse rate could be accurately assessed. The Rev. Stephen Hales (1733) was the first to note that pulse varied with respiration and in 1847 Carl Ludwig was the first to record RSA. With the measurement of the ECG (1895) and advent of digital signal processing techniques in the 1960s, investigation of HRV and its relationship to health and disease has exploded. This essay will conclude with a brief description of time domain, frequency domain, and non-linear dynamic analysis techniques (and their limitations) that are commonly used to measure HRV.

Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial

NARCIS (Netherlands)

van der Zwan, J.E.; de Vente, W.; Huizink, A.C.; Bögels, S.M.; de Bruin, E.I.

2015-01-01

In contemporary western societies stress is highly prevalent, therefore the need for stress-reducing methods is great. This randomized controlled trial compared the efficacy of self-help physical activity (PA), mindfulness meditation (MM), and heart rate variability biofeedback (HRV-BF) in reducing

Effects of social stress on heart rate and heart rate variability in growing pigs

NARCIS (Netherlands)

Jong, de I.C.; Sgoifo, A.; Lambooij, E.; Korte, S.M.; Blokhuis, H.J.; Koolhaas, J.M.

2000-01-01

The effects of social stress on heart rate, heart rate variability and the occurrence of cardiac arrhythmias were studied in 12 growing pigs. Social stress was induced during a good competition test with a pen mate, and subsequently during a resident-intruder test with an unacquainted pig in which

Effects of social stress on heart rate and heart rate variability in growing pigs

NARCIS (Netherlands)

de Jong, IC; Sgoifo, A; Lambooij, E; Korte, SM; Blokhuis, HJ; Koolhaas, JM

The effects of social stress on heart rate, heart rate variability and the occurrence of cardiac arrhythmias were studied in 12 growing pigs. Social stress was induced during a good competition test with a pen mate, and subsequently during a resident-intruder test with an unacquainted pig in which

Heart rate variability in patients with systemic lupus erythematosus: a systematic review and methodological considerations.

Science.gov (United States)

Matusik, P S; Matusik, P T; Stein, P K

2018-07-01

Aim The aim of this review was to summarize current knowledge about the scientific findings and potential clinical utility of heart rate variability measures in patients with systemic lupus erythematosus. Methods PubMed, Embase and Scopus databases were searched for the terms associated with systemic lupus erythematosus and heart rate variability, including controlled vocabulary, when appropriate. Articles published in English and available in full text were considered. Finally, 11 publications were selected, according to the systematic review protocol and were analyzed. Results In general, heart rate variability, measured in the time and frequency domains, was reported to be decreased in patients with systemic lupus erythematosus compared with controls. In some systemic lupus erythematosus studies, heart rate variability was found to correlate with inflammatory markers and albumin levels. A novel heart rate variability measure, heart rate turbulence onset, was shown to be increased, while heart rate turbulence slope was decreased in systemic lupus erythematosus patients. Reports of associations of changes in heart rate variability parameters with increasing systemic lupus erythematosus activity were inconsistent, showing decreasing heart rate variability or no relationship. However, the low/high frequency ratio was, in some studies, reported to increase with increasing disease activity or to be inversely correlated with albumin levels. Conclusions Patients with systemic lupus erythematosus have abnormal heart rate variability, which reflects cardiac autonomic dysfunction and may be related to inflammatory cytokines but not necessarily to disease activity. Thus measurement of heart rate variability could be a useful clinical tool for monitoring autonomic dysfunction in systemic lupus erythematosus, and may potentially provide prognostic information.

Physical Activity and Your Heart

Science.gov (United States)

... causes your heart rate to go up Walking, hiking, jogging, running Water aerobics or swimming laps Bicycling, skateboarding, rollerblading, and jumping rope Ballroom dancing and aerobic dancing Tennis, soccer, hockey, and basketball Benefits of Physical Activity Physical activity has many health ...

The psychology of the heart: Implications for health, physical activity ...

African Journals Online (AJOL)

... for health, physical activity and sport of psychophysiological resonance, coherence and heart rate variability feedback applications involving respiration and facilitation of positive emotion. Keywords: Heart psychology, psychophysiology, resonance, coherence, transcultural context, heart rate variability, biofeedback.

Short- and long-term variations in non-linear dynamics of heart rate variability

DEFF Research Database (Denmark)

Kanters, J K; Højgaard, M V; Agner, E

1996-01-01

OBJECTIVES: The purpose of the study was to investigate the short- and long-term variations in the non-linear dynamics of heart rate variability, and to determine the relationships between conventional time and frequency domain methods and the newer non-linear methods of characterizing heart rate...... rate and describes mainly linear correlations. Non-linear predictability is correlated with heart rate variability measured as the standard deviation of the R-R intervals and the respiratory activity expressed as power of the high-frequency band. The dynamics of heart rate variability changes suddenly...

Dimensional analysis of heart rate variability in heart transplant recipients

Energy Technology Data Exchange (ETDEWEB)

Zbilut, J.P.; Mayer-Kress, G.; Geist, K.

1987-01-01

We discuss periodicities in the heart rate in normal and transplanted hearts. We then consider the possibility of dimensional analysis of these periodicities in transplanted hearts and problems associated with the record.

The Use of Heart Rate Monitors in Physical Education

Science.gov (United States)

Nichols, Randall; Davis, Kathryn L.; McCord, Tim; Schmidt, Dave; Slezak, Alex M.

2009-01-01

The ever-rising rate of obesity and the need for increased physical activity for young children is well documented. Data suggests that today's youth are not participating in enough quality health-enhancing physical activity either in or outside of school. Heart rate monitors have been used by adult exercisers for many years to monitor and assess…

Automatic heart rate normalization for accurate energy expenditure normalization : an analysis of activities of daily living and heart rate features

NARCIS (Netherlands)

Altini, M.; Penders, J.; Vullers, R.J.M.; Amft, O.D.

2014-01-01

Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on "Pervasive Intelligent Technologies for Health". Background: Energy Expenditure (EE) estimation algorithms using Heart Rate (HR) or a combination of accelerometer and HR data suffer from large error due to

Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography

Directory of Open Access Journals (Sweden)

Thomas Penzel

2016-10-01

Full Text Available The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG and cardio-respiratory couplings in a chronological (historical sequence. It presents physiological and pathophysiological insights related to sleep medicine obtained by new technical developments. Recorded nocturnal ECG facilitates conventional heart rate variability analysis, studies of cyclical variations of heart rate, and analysis of ECG waveform. In healthy adults, the autonomous nervous system is regulated in totally different ways during wakefulness, slow-wave sleep, and REM sleep. Analysis of beat-to-beat heart-rate variations with statistical methods enables us to estimate sleep stages based on the differences in autonomic nervous system regulation. Furthermore, up to some degree, it is possible to track transitions from wakefulness to sleep by analysis of heart-rate variations. ECG and heart rate analysis allow assessment of selected sleep disorders as well. Sleep disordered breathing can be detected reliably by studying cyclical variation of heart rate combined with respiration-modulated changes in ECG morphology (amplitude of R wave and T wave.

Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography.

Science.gov (United States)

Penzel, Thomas; Kantelhardt, Jan W; Bartsch, Ronny P; Riedl, Maik; Kraemer, Jan F; Wessel, Niels; Garcia, Carmen; Glos, Martin; Fietze, Ingo; Schöbel, Christoph

2016-01-01

The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However, their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG, and cardio-respiratory couplings in a chronological (historical) sequence. It presents physiological and pathophysiological insights related to sleep medicine obtained by new technical developments. Recorded nocturnal ECG facilitates conventional heart rate variability (HRV) analysis, studies of cyclical variations of heart rate, and analysis of ECG waveform. In healthy adults, the autonomous nervous system is regulated in totally different ways during wakefulness, slow-wave sleep, and REM sleep. Analysis of beat-to-beat heart-rate variations with statistical methods enables us to estimate sleep stages based on the differences in autonomic nervous system regulation. Furthermore, up to some degree, it is possible to track transitions from wakefulness to sleep by analysis of heart-rate variations. ECG and heart rate analysis allow assessment of selected sleep disorders as well. Sleep disordered breathing can be detected reliably by studying cyclical variation of heart rate combined with respiration-modulated changes in ECG morphology (amplitude of R wave and T wave).

On heart rate variability and autonomic activity in homeostasis and in systemic inflammation.

Science.gov (United States)

Scheff, Jeremy D; Griffel, Benjamin; Corbett, Siobhan A; Calvano, Steve E; Androulakis, Ioannis P

2014-06-01

Analysis of heart rate variability (HRV) is a promising diagnostic technique due to the noninvasive nature of the measurements involved and established correlations with disease severity, particularly in inflammation-linked disorders. However, the complexities underlying the interpretation of HRV complicate understanding the mechanisms that cause variability. Despite this, such interpretations are often found in literature. In this paper we explored mathematical modeling of the relationship between the autonomic nervous system and the heart, incorporating basic mechanisms such as perturbing mean values of oscillating autonomic activities and saturating signal transduction pathways to explore their impacts on HRV. We focused our analysis on human endotoxemia, a well-established, controlled experimental model of systemic inflammation that provokes changes in HRV representative of acute stress. By contrasting modeling results with published experimental data and analyses, we found that even a simple model linking the autonomic nervous system and the heart confound the interpretation of HRV changes in human endotoxemia. Multiple plausible alternative hypotheses, encoded in a model-based framework, equally reconciled experimental results. In total, our work illustrates how conventional assumptions about the relationships between autonomic activity and frequency-domain HRV metrics break down, even in a simple model. This underscores the need for further experimental work towards unraveling the underlying mechanisms of autonomic dysfunction and HRV changes in systemic inflammation. Understanding the extent of information encoded in HRV signals is critical in appropriately analyzing prior and future studies. Copyright © 2014 Elsevier Inc. All rights reserved.

Clinical efficacy of efonidipine hydrochloride, a T-type calcium channel inhibitor, on sympathetic activities. Examination using spectral analysis of heart rate/blood pressure variabilities and 123I-Metaiodobenzylguanidine myocardial scintigraphy

International Nuclear Information System (INIS)

Harada, Kenji; Nomura, Masahiro; Nishikado, Akiyoshi; Uehara, Kouzoh; Nakaya, Yutaka; Ito, Susumu

2003-01-01

Dihydropyridine Ca antagonists cause reflex tachycardia related to their hypotensive effects. Efonidipine hydrochloride has inhibitory effects on T-type Ca channels, even as it inhibits reflex tachycardia. In the present study, the influence of efonidipine hydrochloride on heart rate and autonomic nervous function was investigated. Using an electrocardiogram and a tonometric blood pressure measurement, autonomic nervous activity was evaluated using spectral analysis of heart rate/systolic blood pressure variability. Three protocols were used: a single dose of efonidipine hydrochloride was administered orally to healthy subjects with resting heart rate values of 75 beats/min or more (high-heart rate (HR) group) and to healthy subjects with resting heart rate values less than 75 beats/min (low-HR group); efonidipine hydrochloride was newly administered to untreated patients with essential hypertension, and autonomic nervous activity was investigated after a 4-week treatment period; and patients with high heart rate values (≥75 beats/min) who had been treated with a dihydropyridine L-type Ca channel inhibitor for 1 month or more were switched to efonidipine hydrochloride and any changes in autonomic nervous activity were investigated. In all protocols, administration of efonidipine hydrochloride decreased the heart rate in patients with a high heart rate, reduced sympathetic nervous activity, and enhanced parasympathetic nervous activity. In addition, myocardial scintigraphy with 123 I-metaiodobenzylguanidine showed significant improvement in the washout rate and heart to mediastinum (H/M) ratio of patients who were switched from other dihydropyridine Ca antagonists to efonidipine hydrochloride. Efonidipine hydrochloride inhibits increases in heart rate and has effects on the autonomic nervous system. It may be useful for treating hypertension and angina pectoris, and may also have a cardiac protective function. (author)

Decrease in heart rate after longitudinal participation in the Groningen Active Living Model (GALM) recreational sports programme

NARCIS (Netherlands)

de Jong, Johan; Lemmink, Koen; Scherder, Erik; Stewart, Roy; King, Abby; Stevens, Martin

2009-01-01

The aim of this study was to investigate changes in heart rate during submaximal exercise as an index of cardiovascular function in older adults participating in the Groningen Active Living Model recreational sports programme who were sedentary or underactive at baseline. A repeated measurement

Longitudinal changes in heart rate after participating in the Groningen Active Living Model (GALM) recreational sports programme

NARCIS (Netherlands)

de Jong, Johan; Lemmink, Koen; Scherder, Erik; Stewart, Roy; King, Abby C.

2009-01-01

The aim of this study was to investigate changes in heart rate during submaximal exercise as an index of cardiovascular function in older adults participating in the Groningen Active Living Model recreational sports programme who were sedentary or underactive at baseline. A repeated measurement

Analyses of heart rate variability in young soccer players: the effects of sport activity.

Science.gov (United States)

Bricout, Véronique-Aurélie; Dechenaud, Simon; Favre-Juvin, Anne

2010-04-19

The use of heart rate variability (HRV) in the management of sport training is a practice which tends to spread, especially in order to prevent the occurrence of states of fatigue. To estimate the HRV parameters obtained using a heart rate recording, according to different loads of sporting activities, and to make the possible link with the appearance of fatigue. Eight young football players, aged 14.6 years+/-2 months, playing at league level in Rhône-Alpes, training for 10 to 20 h per week, were followed over a period of 5 months, allowing to obtain 54 recordings of HRV in three different conditions: (i) after rest (ii) after a day with training and (iii) after a day with a competitive match. Under the effect of a competitive match, the HRV temporal indicators (heart rate, RR interval, and pNN50) were significantly altered compared to the rest day. The analysis of the sympathovagal balance rose significantly as a result of the competitive constraint (0.72+/-0.17 vs. 0.90+/-0.20; pHRV is an objective and non-invasive monitoring of management of the training of young sportsmen. HRV analysis allowed to highlight any neurovegetative adjustments according to the physical loads. Thus, under the effect of an increase of physical and psychological constraints that a football match represents, the LF/HF ratio rises significantly; reflecting increased sympathetic stimulation, which beyond certain limits could be relevant to prevent the emergence of a state of fatigue. 2009 Elsevier B.V. All rights reserved.

Heart Rate Monitors Promote Physical Education for Children

Science.gov (United States)

Tipton, Jan; Sander, Allan N.

2004-01-01

National health and fitness data suggests that a significant percentage of children are not on a pathway to leading healthy, physically active lifestyles. Many children are leading sedentary lifestyles due to a lack of opportunity, success, or self-motivation in physical activity. Programs that highlight the use of heart rate monitors offer a…

Heart Rates of Elementary Physical Education Students during the Dancing Classrooms Program

Science.gov (United States)

Nelson, Larry; Evans, Melissa; Guess, Wendy; Morris, Mary; Olson, Terry; Buckwalter, John

2011-01-01

We examined how different types of dance activities, along with their duration, influenced heart rate responses among fifth-grade physical education students (N = 96) who participated in the Dancing Classrooms program. Results indicated that the overall Dancing Classrooms program elicits a moderate cardiovascular heart rate response (M = 124.4…

Heart-Rate Recovery After Warm-up in Swimming: A Useful Predictor of Training Heart-Rate Response?

Science.gov (United States)

Ganzevles, Sander P M; de Haan, Arnold; Beek, Peter J; Daanen, Hein A M; Truijens, Martin J

2017-07-01

For training to be optimal, daily training load has to be adapted to the momentary status of the individual athlete, which is often difficult to establish. Therefore, the current study investigated the predictive value of heart-rate recovery (HRR) during a standardized warm-up for training load. Training load was quantified by the variation in heart rate during standardized training in competitive swimmers. Eight female and 5 male Dutch national-level swimmers participated in the study. They all performed 3 sessions consisting of a 300-m warm-up test and a 10 × 100-m training protocol. Both protocols were swum in front crawl at individually standardized velocities derived from an incremental step test. Velocity was related to 75% and 85% heart-rate reserve (% HR res ) for the warm-up and training, respectively. Relative HRR during the first 60 s after the warm-up (HR Rw-up ) and differences between the actual and intended heart rate for the warm-up and the training (ΔHR w-up and ΔHR tr ) were determined. No significant relationship between HRR w-up and ΔHR tr was found (F 1,37 = 2.96, P = .09, R 2 = .07, SEE = 4.65). There was considerable daily variation in ΔHR tr at a given swimming velocity (73-93% HR res ). ΔHR w-up and ΔHR tr were clearly related (F 1,37 = 74.31, P warm-up does not predict heart rate during a directly subsequent and standardized training session. Instead, heart rate during the warm-up protocol seems a promising alternative for coaches to make daily individual-specific adjustments to training programs.

Blood pressure and heart rate adjustment following acute Frenkel's ...

African Journals Online (AJOL)

Background: Frenkel's ambulatory activity has been routinely employed by physiotherapists for rehabilitation of gait coordination, however, its immediate influence on blood pressure and heart rate has not been investigated. Objective: To investigate the acute effect of Frenkel's ambulatory activity on blood pressure and ...

Heart rate profile during exercise in patients with early repolarization.

Science.gov (United States)

Cay, Serkan; Cagirci, Goksel; Atak, Ramazan; Balbay, Yucel; Demir, Ahmet Duran; Aydogdu, Sinan

2010-09-01

Both early repolarization and altered heart rate profile are associated with sudden death. In this study, we aimed to demonstrate an association between early repolarization and heart rate profile during exercise. A total of 84 subjects were included in the study. Comparable 44 subjects with early repolarization and 40 subjects with normal electrocardiogram underwent exercise stress testing. Resting heart rate, maximum heart rate, heart rate increment and decrement were analyzed. Both groups were comparable for baseline characteristics including resting heart rate. Maximum heart rate, heart rate increment and heart rate decrement of the subjects in early repolarization group had significantly decreased maximum heart rate, heart rate increment and heart rate decrement compared to control group (all P decrement (multiple-adjusted OR of the risk of presence of early repolarization was 2.98 (95%CI 1.21-7.34) (P = 0.018) and 7.73 (95%CI 2.84-21.03) (P decrement compared to higher levels, respectively. Subjects with early repolarization have altered heart rate profile during exercise compared to control subjects. This can be related to sudden death.

Continuous measurement of heart rate variability following carbon ...

African Journals Online (AJOL)

2010-07-16

Jul 16, 2010 ... Power spectral analysis of the electrocardiographic R-R interval [heart rate variability: (HRV)] is a well known, non- invasive method for assessing autonomic nervous activity.1. Studies using HRV analysis during positive-pressure pneumoperitoneum (PPP) have demonstrated increased sympathetic ...

Genome-wide association studies and resting heart rate

DEFF Research Database (Denmark)

Oskari Kilpeläinen, Tuomas

2016-01-01

Genome-wide association studies (GWASs) have revolutionized the search for genetic variants regulating resting heart rate. In the last 10 years, GWASs have led to the identification of at least 21 novel heart rate loci. These discoveries have provided valuable insights into the mechanisms...... and pathways that regulate heart rate and link heart rate to cardiovascular morbidity and mortality. GWASs capture majority of genetic variation in a population sample by utilizing high-throughput genotyping chips measuring genotypes for up to several millions of SNPs across the genome in thousands...... of individuals. This allows the identification of the strongest heart rate associated signals at genome-wide level. While GWASs provide robust statistical evidence of the association of a given genetic locus with heart rate, they are only the starting point for detailed follow-up studies to locate the causal...

Behaviour, heart rate, and heart rate variability in pigs exposed to novelty

Directory of Open Access Journals (Sweden)

Manja Zupan

2016-03-01

Full Text Available ABSTRACT In the present study, we investigated behavioural responses and determined parameters of heart rate variability (HRV to elucidate a relative activation of autonomic nervous system (ANS during baseline (10 min and in response to potentially stressful situations (10 min in two pig breeds and sexes. Gilts (n = 21 and barrows (n = 9 of the Landrace × Yorkshire (LY; n = 15 and Landrace/Yorkshire × Landrace/Duroc (LYLD; n = 15 breeds were subjected to a novel object test (NOT and a novel arena test (NAT. Basal ANS state differed in pigs across breeds but not sexes. Landrace × Yorkshire pigs had a significantly lower basal heart rate (HR and low-frequency band (LF with a higher root mean square of successive interbeat intervals (RMSSD and high-frequency band (HF than LYLD pigs. In the NOT, despite having similar cardiac responses, gilts had a longer duration of contact with a novel object, higher lying and standing duration, and a lower duration of walking compared with barrows. In the NAT, we found similar behaviour across sexes but a different degree of ANS state, with barrows having a significantly higher increase in LF/HF (power of the low frequency component divided by the power of the high-frequency band compared with gilts. Landrace/Yorkshire × Landrace/Duroc pigs showed longer duration of contact with a novel object in the NOT accompanied by less lying and standing than LY pigs in both tests. No difference in ANS activation between breeds was found in the NOT. In the NAT, HR increased more from baseline to testing in LY pigs than in LYLD pigs. There is a complex and often contradictory nature of relationships between behaviour and cardiac responses to novelty in pigs of different breeds and sexes.

Heart-Rate Recovery Index Is Impaired in Behçet's Disease

Science.gov (United States)

Kaya, Ergun Baris; Yorgun, Hikmet; Akdogan, Ali; Ates, Ahmet Hakan; Canpolat, Ugur; Sunman, Hamza; Aytemir, Kudret; Tokgozoglu, Lale; Kabakci, Giray; Calguneri, Meral; Ozkutlu, Hilmi; Oto, Ali

2009-01-01

Behçet's disease, a multisystemic inflammatory disorder, has been associated with a number of cardiovascular dysfunctions, including ventricular arrhythmias and sudden cardiac death. Heart-rate recovery after exercise can provide both an estimate of impaired parasympathetic tone and a prognosis in regard to all-cause and cardiovascular death. The aim of our study was to evaluate heart-rate recovery in Behçet's disease From January through July 2008, we examined at our outpatient clinic and prospectively enrolled 30 consecutive patients with Behçet's disease and 50 healthy control participants who were matched for age and sex. Basal electrocardiography, echocardiography, and treadmill exercise testing were performed in all patients and control participants. The heart-rate recovery index was calculated in the usual manner, by subtracting the 1st-minute (Rec1), 2nd-minute (Rec2), and 3rd-minute (Rec3) recovery heart rates from the maximal heart rate after exercise stress testing. Patients with Behçet's disease exhibited significantly lower heart-rate recovery numbers, compared with healthy control participants: Rec1, 24.28 ± 8.2 vs 34.4 ± 7.6, P = 0.002; Rec2, 49.28 ± 11.2 vs 57.5 ± 7.0, P < 0.05; and Rec3, 56.2 ± 12.11 vs 67.4 ± 8.7, P = 0.014. To our knowledge, this is the 1st study that shows an impaired heart-rate recovery index (indicative of reduced parasympathetic activity) among patients with Behçet's disease. Given the independent prognostic value of the heart-rate recovery index, our results may explain the increased occurrence of arrhythmias and sudden cardiac death in Behçet's patients. Therefore, this index may be clinically useful in the identification of high-risk patients. PMID:19693299

Onset of decreased heart work is correlated with increased heart rate and shortened QT interval in high-carbohydrate fed overweight rats.

Science.gov (United States)

Durak, Aysegul; Olgar, Yusuf; Tuncay, Erkan; Karaomerlioglu, Irem; Kayki Mutlu, Gizem; Arioglu Inan, Ebru; Altan, Vecdi Melih; Turan, Belma

2017-11-01

Mechanical activity of the heart is adversely affected in metabolic syndrome (MetS) characterized by increased body mass and marked insulin resistance. Herein, we examined the effects of high carbohydrate intake on cardiac function abnormalities by evaluating in situ heart work, heart rate, and electrocardiograms (ECGs) in rats. MetS was induced in male Wistar rats by adding 32% sucrose to drinking water for 22-24 weeks and was confirmed by insulin resistance, increased body weight, increased blood glucose and serum insulin, and increased systolic and diastolic blood pressures in addition to significant loss of left ventricular integrity and increased connective tissue around myofibrils. Analysis of in situ ECG recordings showed a markedly shortened QT interval and decreased QRS amplitude with increased heart rate. We also observed increased oxidative stress and decreased antioxidant defense characterized by decreases in serum total thiol level and attenuated paraoxonase and arylesterase activities. Our data indicate that increased heart rate and a shortened QT interval concomitant with higher left ventricular developed pressure in response to β-adrenoreceptor stimulation as a result of less cyclic AMP release could be regarded as a natural compensation mechanism in overweight rats with MetS. In addition to the persistent insulin resistance and obesity associated with MetS, one should consider the decreased heart work, increased heart rate, and shortened QT interval associated with high carbohydrate intake, which may have more deleterious effects on the mammalian heart.

Heart Rate and Liking During "Kinect Boxing" Versus "Wii Boxing": The Potential for Enjoyable Vigorous Physical Activity Videogames.

Science.gov (United States)

Sanders, Gabriel J; Peacock, Corey A; Barkley, Jacob E; Gish, Brian; Brock, Scott; Volpenhein, Josh

2015-08-01

Nintendo(®) (Kyoto, Japan) "Wii™ Sports Boxing" ("Wii Boxing") and Xbox(®) (Microsoft, Redmond, WA) "Kinect(®) Sports Boxing" ("Kinect Boxing") are both boxing simulation videogames that are available for two different active videogame (AVG) systems. Although these AVGs are similar, the style of gameplay required is different (i.e., upper body only versus total body movements) and may alter physical activity intensity and one's preference for playing one game over the other. AVGs that elicit the greatest physiologic challenge and are preferred by users should be identified in an effort to enhance the efficacy of physical activity interventions and programs that include AVGs. The mean heart rate (HRmean) and peak heart rate (HRpeak) for 27 adults (22.7±4.2 years old) were recorded during four 10-minute conditions: seated rest, treadmill walking at 3 miles/hour, "Wii Boxing," and "Kinect Boxing." Upon completion of all four conditions, participants indicated which condition they preferred, and HRmean and HRpeak were calculated as a percentage of age-predicted maximum heart rate to classify physical activity intensity for the three activity conditions (treadmill, "Wii Boxing," and "Kinect Boxing"). "Kinect Boxing" significantly (P<0.001) increased percentage HRmean (64.1±1.6 percent of age-predicted maximum) and percentage HRpeak (76.5±1.9 percent) above all other conditions: Wii HRmean, 53.0±1.2 percent; Wii HRpeak, 61.8±1.5 percent; treadmill HRmean, 52.4±1.2 percent; treadmill HRpeak, 55.2±2.2 percent. Percentage HRpeak for "Kinect Boxing" was great enough to be considered a vigorous-intensity physical activity. There was no difference (P=0.55) in percentage HRmean between "Wii Boxing" and treadmill walking. Participants also preferred "Kinect Boxing" (P<0.001; n=26) to all other conditions ("Wii Boxing," n=1; treadmill n=0). "Kinect Boxing" was the most preferred and the only condition that was physiologically challenging enough to be classified as a

Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice

DEFF Research Database (Denmark)

Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

2011-01-01

Neurons of the brain's biological clock located in the hypothalamic suprachiasmatic nucleus (SCN) generate circadian rhythms of physiology (core body temperature, hormone secretion, locomotor activity, sleep/wake, and heart rate) with distinct temporal phasing when entrained by the light/dark (LD......) cycle. The neuropeptide vasoactive intestinal polypetide (VIP) and its receptor (VPAC2) are highly expressed in the SCN. Recent studies indicate that VIPergic signaling plays an essential role in the maintenance of ongoing circadian rhythmicity by synchronizing SCN cells and by maintaining rhythmicity...... within individual neurons. To further increase the understanding of the role of VPAC2 signaling in circadian regulation, we implanted telemetric devices and simultaneously measured core body temperature, spontaneous activity, and heart rate in a strain of VPAC2-deficient mice and compared...

Peak heart rates at extreme altitudes

DEFF Research Database (Denmark)

Lundby, C; Van Hall, Gerrit

2001-01-01

We have measured maximal heart rate during a graded maximal bicycle exercise test to exhaustion in five healthy climbers before and during an expedition to Mt. Everest. Maximal heart rates at sea level were 186 (177-204) beats/min(-1) at sea level and 170 (169-182) beats/min(-1) with acute hypoxi...

A healthy heart is not a metronome: an integrative review of the heart's anatomy and heart rate variability.

Science.gov (United States)

Shaffer, Fred; McCraty, Rollin; Zerr, Christopher L

2014-01-01

Heart rate variability (HRV), the change in the time intervals between adjacent heartbeats, is an emergent property of interdependent regulatory systems that operate on different time scales to adapt to challenges and achieve optimal performance. This article briefly reviews neural regulation of the heart, and its basic anatomy, the cardiac cycle, and the sinoatrial and atrioventricular pacemakers. The cardiovascular regulation center in the medulla integrates sensory information and input from higher brain centers, and afferent cardiovascular system inputs to adjust heart rate and blood pressure via sympathetic and parasympathetic efferent pathways. This article reviews sympathetic and parasympathetic influences on the heart, and examines the interpretation of HRV and the association between reduced HRV, risk of disease and mortality, and the loss of regulatory capacity. This article also discusses the intrinsic cardiac nervous system and the heart-brain connection, through which afferent information can influence activity in the subcortical and frontocortical areas, and motor cortex. It also considers new perspectives on the putative underlying physiological mechanisms and properties of the ultra-low-frequency (ULF), very-low-frequency (VLF), low-frequency (LF), and high-frequency (HF) bands. Additionally, it reviews the most common time and frequency domain measurements as well as standardized data collection protocols. In its final section, this article integrates Porges' polyvagal theory, Thayer and colleagues' neurovisceral integration model, Lehrer et al.'s resonance frequency model, and the Institute of HeartMath's coherence model. The authors conclude that a coherent heart is not a metronome because its rhythms are characterized by both complexity and stability over longer time scales. Future research should expand understanding of how the heart and its intrinsic nervous system influence the brain.

Single unit activity in the medial prefrontal cortex during Pavlovian heart rate conditioning: Effects of peripheral autonomic blockade.

Science.gov (United States)

Powell, D A; Ginsberg, Jay P

2005-11-01

Electrical activity was recorded from single neurons in the medial prefrontal cortex of rabbits during differential Pavlovian heart rate (HR) conditioning. A heterogeneous population of cells were found, some of which showed CS-evoked increases and others CS-evoked decreases in discharge, while some cells were biphasic. A subset of cells also showed trial-related changes in discharge that were related to acquisition of the HR discrimination between the reinforced CS+ and non-reinforced CS-. Administration of the peripheral cholinergic antagonist, methylscopolamine, and the andrenergic antagonist, atenolol, either increased or decreased maintained baseline activity of many cells, but had little or no effect on the CS-evoked activity of these cells. Waveform changes also did not result from administration of these drugs. This finding suggests that CS-evoked mPFC activity is not being driven by cardiac afferent input to CNS cardiac control centers. Previous studies have shown that ibotenic acid lesions of this area greatly decreases the magnitude of decelerative heart rate conditioned responses; the latter finding, plus the results of the present study, suggest that processing of CS/US contingencies by the prefrontal cortex contributes to the acquisition of autonomic changes during Pavlovian conditioning.

The effect of relaxing music on heart rate and heart rate variability during ECG GATED-myocardial perfusion scintigraphy.

Science.gov (United States)

Tan, Yusuf Ziya; Ozdemir, Semra; Temiz, Ahmet; Celik, Fatmanur

2015-05-01

The positive changes in human behavior caused by relaxing music demonstrate the psychological effect of music on human body. A meta-analytical study has shown that relaxing music affects blood pressure and heart rate in coronary heart patients and cancer patients. The aim of our study is to research whether there is a significant effect on heart rate and heart rate variability due to listening to relaxing music during ECG GATED MPS imaging under gamma camera. The music group (n = 50 patients) could choose from 15 different musical types including folk music (no lyric). The other 50 patients were placed in a "no music group" and did not get headphones or any music. There was a statistically significant reduction in the heart rate of patients in the music group compared to those in the control group. Relaxing music provides great benefits to both patient and clinician. There is close relationship between relaxing music and health procedure, can use every area of the health noninvasiv, safe, cheap and is a method don't have side effect. Copyright © 2015 Elsevier Ltd. All rights reserved.

Global Bi-ventricular endocardial distribution of activation rate during long duration ventricular fibrillation in normal and heart failure canines.

Science.gov (United States)

Luo, Qingzhi; Jin, Qi; Zhang, Ning; Han, Yanxin; Wang, Yilong; Huang, Shangwei; Lin, Changjian; Ling, Tianyou; Chen, Kang; Pan, Wenqi; Wu, Liqun

2017-04-13

The objective of this study was to detect differences in the distribution of the left and right ventricle (LV & RV) activation rate (AR) during short-duration ventricular fibrillation (SDVF, 1 min) in normal and heart failure (HF) canine hearts. Ventricular fibrillation (VF) was electrically induced in six healthy dogs (control group) and six dogs with right ventricular pacing-induced congestive HF (HF group). Two 64-electrode basket catheters deployed in the LV and RV were used for global endocardium electrical mapping. The AR of VF was estimated by fast Fourier transform analysis from each electrode. In the control group, the LV was activated faster than the RV in the first 20 s, after which there was no detectable difference in the AR between them. When analyzing the distribution of the AR within the bi-ventricles at 3 min of LDVF, the posterior LV was activated fastest, while the anterior was slowest. In the HF group, a detectable AR gradient existed between the two ventricles within 3 min of VF, with the LV activating more quickly than the RV. When analyzing the distribution of the AR within the bi-ventricles at 3 min of LDVF, the septum of the LV was activated fastest, while the anterior was activated slowest. A global bi-ventricular endocardial AR gradient existed within the first 20 s of VF but disappeared in the LDVF in healthy hearts. However, the AR gradient was always observed in both SDVF and LDVF in HF hearts. The findings of this study suggest that LDVF in HF hearts can be maintained differently from normal hearts, which accordingly should lead to the development of different management strategies for LDVF resuscitation.

Measuring heart rate with optical sensor

NARCIS (Netherlands)

Barachi, M. (Mitra)

2014-01-01

The problem addressed in this report is to verify the possibility of using an optical sensor in the SaxShirt in order to extract the heart rate. There are specifically three questions that we try to address. 1) How is it possible to extract heart rate (BPM) from the optical sensor? 2) Is it

Real-time relationship between PKA biochemical signal network dynamics and increased action potential firing rate in heart pacemaker cells: Kinetics of PKA activation in heart pacemaker cells.

Science.gov (United States)

Yaniv, Yael; Ganesan, Ambhighainath; Yang, Dongmei; Ziman, Bruce D; Lyashkov, Alexey E; Levchenko, Andre; Zhang, Jin; Lakatta, Edward G

2015-09-01

cAMP-PKA protein kinase is a key nodal signaling pathway that regulates a wide range of heart pacemaker cell functions. These functions are predicted to be involved in regulation of spontaneous action potential (AP) generation of these cells. Here we investigate if the kinetics and stoichiometry of increase in PKA activity match the increase in AP firing rate in response to β-adrenergic receptor (β-AR) stimulation or phosphodiesterase (PDE) inhibition, that alters the AP firing rate of heart sinoatrial pacemaker cells. In cultured adult rabbit pacemaker cells infected with an adenovirus expressing the FRET sensor AKAR3, the EC50 in response to graded increases in the intensity of β-AR stimulation (by Isoproterenol) the magnitude of the increases in PKA activity and the spontaneous AP firing rate were similar (0.4±0.1nM vs. 0.6±0.15nM, respectively). Moreover, the kinetics (t1/2) of the increases in PKA activity and spontaneous AP firing rate in response to β-AR stimulation or PDE inhibition were tightly linked. We characterized the system rate-limiting biochemical reactions by integrating these experimentally derived data into a mechanistic-computational model. Model simulations predicted that phospholamban phosphorylation is a potent target of the increase in PKA activity that links to increase in spontaneous AP firing rate. In summary, the kinetics and stoichiometry of increases in PKA activity in response to a physiological (β-AR stimulation) or pharmacological (PDE inhibitor) stimuli match those of changes in the AP firing rate. Thus Ca(2+)-cAMP/PKA-dependent phosphorylation limits the rate and magnitude of increase in spontaneous AP firing rate. Copyright © 2015 Elsevier Ltd. All rights reserved.

Study Heart Rate by Tools from Complex Networks

International Nuclear Information System (INIS)

Makowiec, D.; Wdowczyk-Szulc, J.; Zarczynska-Buchowiecka, M.; Gruchala, M.; Rynkiewicz, A.

2011-01-01

Heart rate measured as beat-to-beat time intervals varies in time. It is believed that time intervals between subsequent normal heart contractions carry information about the regulatory system of the heart. How to quantify such signals is not clear and because of that heart rate variability is still apart from the clinic routine. In the following, we propose a method for representing a heart rate signal as a directed network. Then we study the signal properties by complex network tools. The signals to study were collected from patients recovering after the heart transplantation. The aim is to classify the progress of adapting of the new heart - graft. Moreover, it is expected that the method allows for visual classification. Our investigations are preliminary, however the obtained results are promising. (authors)

[Increased sympathetic activity assessed by spectral analysis of heart rate variability in patients with CRPS I].

Science.gov (United States)

Schulze, J; Troeger, C

2010-02-01

The complex regional pain syndrome type I (CRPS I) is a painful neuropathic disorder with an antecedent disproportionate trauma leading to spontaneous pain, hyperalgesia, impaired motor function, swelling, changes in sweating and vascular abnormalities without nerve injury. Whether this syndrome is the result of central or peripheral autonomic dysfunction is still a matter of debate. The purpose of this study was to determine the activity of the sympathetic nervous system in patients with CRPS I by power spectral analysis of heart rate variability. This is a pilot study on 6 patients (mean age 50 years; 4 female, 2 male) diagnosed as suffering from CRPS I and 6 age-matched healthy controls. In the pain-free interval and after taking rest for 5 min, 512 subsequent heart beats were obtained with an ECG standard lead II in the supine and then sitting position. Using an autoregressive model, power spectral densities were calculated for the following frequency bands: CRPS I compared to the healthy controls in the supine position (LF/HF=4.01 vs. LF/HF=1.27; p=0.041). The application of stress by changing to the sitting position even increased that difference (6.72 vs. 1.93). Our results support the hypothesis that the pathogenesis of the early stage CRPS I might be related to an increased sympathetic activity. By assessing the autonomic influence on the heart rate variability in CRPS I patients we could also conclude that this disturbance occurs rather at a central level. Georg Thieme Verlag KG Stuttgart, New York.

Heart rate variability reveals that a decrease in parasympathetic ('rest-and-digest') activity dominates autonomic stress responses in a free-living seabird.

Science.gov (United States)

Müller, Martina S; Vyssotski, Alexei L; Yamamoto, Maki; Yoda, Ken

2017-10-01

The autonomic stress response, often referred to as the 'fight-or-flight' response, is a highly conserved physiological reaction to stress in vertebrates that occurs via a decrease in parasympathetic (PNS) activity, which promotes self-maintenance 'rest and digest' processes, and an increase in sympathetic (SNS) activity, which prepares an animal for danger ('fight-or-flight'). Though the PNS and SNS both innervate most organs, they often control different tissues and functions within those organs (though the pacemaker of the heart is controlled by both). Moreover the PNS and SNS are regulated independently. Yet until now, most studies of autonomic stress responses in non-model species focused only on the SNS response. We used external electrocardiogram loggers to measure heart rate and heart rate variability indexes that reflect PNS and SNS activity in a seabird, the Streaked Shearwater (Calonectris leucomelas), during the stress of handling, and during recovery in the nest burrow or during restraint in a cloth bag. We show for the first time in a free-living animal that the autonomic stress response is mediated primarily by a rapid decrease in PNS activity: handling stress induced a large and long-lasting depression of PNS 'rest-and-digest' activity that required two hours to recover. We also found evidence for a substantially smaller and shorter-lasting SNS 'fight-or-flight' response. Confinement in a cloth bag was less stressful for birds than handling, but more stressful than recovering in nest burrows. We show that quantifying autonomic activity from heart rate variability is effective for non-invasively studying stress physiology in free-living animals. Copyright © 2017 Elsevier Inc. All rights reserved.

Guided imagery, anxiety, heart rate, and heart rate variability during centrifuge training.

Science.gov (United States)

Jing, Xiaolu; Wu, Ping; Liu, Fang; Wu, Bin; Miao, Danmin

2011-02-01

Centrifuge training is an important method of improving the hypergravity tolerance of pilots, cosmonauts, and Chinese astronauts. However, the concomitants of tension or anxiety often impede training. Guided imagery (GI), a mind-body relaxation technique, provides a behavioral and cognitive means whereby individuals are able to exert control over the focus of attention. This study aims to investigate the immediate effects of GI for reducing stress in centrifuge training. There were 12 healthy young men who were randomly assigned to a GI group or music group. We measured changes in heart rate during centrifuge training, in heart rate variability before and after centrifuge training, and also evaluated relaxation and anxiety in three phases: before intervention, after intervention, and following centrifuge training. The change in the pattern of anxiety was different in the two groups over the three phases. Anxiety (measured by State Anxiety Inventory) in the GI group changed from 31.7 +/- 5.9 to 26.8 +/- 2.6 and 27.8 +/- 4.1, whereas for the music group this changed from 32.2 +/- 7.6 to 31.2 +/- 8.3 and 26.8 +/- 6.8. During centrifuge training, the maximal HR for the GI group (101.2 +/- 8.8) was lower than that of the music group (123.0 +/- 19.1). In addition GI showed a decrease in low frequency (LF, 0.04-0.15 Hz) components and an increase in high frequency (HF, 0.15-0.4 Hz) components before and after centrifuge training. GI was capable of decreasing tension, anxiety, and sympathetic nervous system activity pre- or post-centrifugation.

Predictive value of casual ECG-based resting heart rate compared with resting heart rate obtained from Holter recording

DEFF Research Database (Denmark)

Carlson, Nicholas; Dixen, Ulrik; Marott, Jacob L

2014-01-01

BACKGROUND: Elevated resting heart rate (RHR) is associated with cardiovascular mortality and morbidity. Assessment of heart rate (HR) from Holter recording may afford a more precise estimate of the effect of RHR on cardiovascular risk, as compared to casual RHR. Comparative analysis was carried ...

Impact of space weather on human heart rate during the years 2011-2013

Science.gov (United States)

Galata, E.; Ioannidou, S.; Papailiou, M.; Mavromichalaki, H.; Paravolidakis, K.; Kouremeti, M.; Rentifis, L.; Simantirakis, E.; Trachanas, K.

2017-08-01

During the last years a possible link between different levels of solar and geomagnetic disturbances and human physiological parameters is suggested by several published studies. In this work the examination of the potential association between heart rate variations and specific space weather activities was performed. A total of 482 individuals treated at Hippocratio General Hospital in Athens, the Cardiology clinics of Nikaia General Hospital in Piraeus and the Heraklion University Hospital in Crete, Greece, were assessed from July 2011 to April 2013. The heart rate of the individuals was recorded by a Holter monitor on a n hourly basis, while the hourly variations of the cosmic ray intensity measured by the Neutron Monitor Station of the Athens University and of the geomagnetic index Dst provided by the Kyoto Observatory were used. The ANalysis Of VAriance (ANOVA) and the Multiple Linear Regression analysis were used for analysis of these data. A statistically significant effect of both cosmic rays and geomagnetic activity on heart rate was observed, which may indicate that changes in space weather could be linked to heart rate variations.

QRS peak detection for heart rate monitoring on Android smartphone

Science.gov (United States)

Pambudi Utomo, Trio; Nuryani, Nuryani; Darmanto

2017-11-01

In this study, Android smartphone is used for heart rate monitoring and displaying electrocardiogram (ECG) graph. Heart rate determination is based on QRS peak detection. Two methods are studied to detect the QRS complex peak; they are Peak Threshold and Peak Filter. The acquisition of ECG data is utilized by AD8232 module from Analog Devices, three electrodes, and Microcontroller Arduino UNO R3. To record the ECG data from a patient, three electrodes are attached to particular body’s surface of a patient. Patient’s heart activity which is recorded by AD8232 module is decoded by Arduino UNO R3 into analog data. Then, the analog data is converted into a voltage value (mV) and is processed to get the QRS complex peak. Heart rate value is calculated by Microcontroller Arduino UNO R3 uses the QRS complex peak. Voltage, heart rate, and the QRS complex peak are sent to Android smartphone by Bluetooth HC-05. ECG data is displayed as the graph by Android smartphone. To evaluate the performance of QRS complex peak detection method, three parameters are used; they are positive predictive, accuracy and sensitivity. Positive predictive, accuracy, and sensitivity of Peak Threshold method is 92.39%, 70.30%, 74.62% and for Peak Filter method are 98.38%, 82.47%, 83.61%, respectively.

The relationship between phase and heart rate

International Nuclear Information System (INIS)

Underwood, S.R.; Walton, S.; Brown, N.J.G.; Laming, P.J.; Ell, P.J.; Emanuel, R.W.; Swanton, R.H.

1984-01-01

The Fourier phase image is used in rest and stress radionuclide angiocardiography to assess the timing of ventricular wall motion in a regional fashion, and areas of high phase are taken to reprensent areas of delayed contraction. However, phase increases with heart rate and this can make interpretation difficult. This study investigates the relationship between phase and heart rate. A heterogenous group of 43 subjects was studied by ECG-gated equilibrium radionuclide angiocardiography, all of the subjects having normal extent of left ventricular wall motion as judged by normal ejection fraction and normal amplitude image. Mean left ventricular phase correlated well with mean time of end systole (r=0.92), but there was no correlation with time of end diastole.Thus phase reflects the time of end systole as a proportion of cycle length and should be linearly related to heart rate provided the duration of systole is unchanged. In 28 normal subjects mean left ventricular phase correlated linearly with resting rate (r=0.91), and when exercised the relationship was maintained up to 90 beats per minute. Above this rate the increases were less marked as the duration of systole shortened. The same was true in 4 subjects paced at different rates. Mean resting heart rate in the normal subjects was 70 beats per minute and correcting phase linearly to rate 70 did not change mean left ventricular phase but did decrease the standard deviation from 18 degree to 12 degree. It is concluded that correcting phase for heart rate below 90 beats per minute will increase the sensitivity of the phase image to abnormalities of the timing of ventricular contraction. This correction should be appropriate in resting, isometric exercise, and cold pressor studies but because of the higher heart rates involved will not be appropriate for bicycle exercise. (Author)

The effect of metaprolol alone and metaprolol plus bromazepam on heart rate and heart rate variability during multislice computed tomography angiography

International Nuclear Information System (INIS)

Tuyyab, F.; Naeem, M.Y.; Maken, G.R.; Najfi, M.H.; Hassan, F.

2012-01-01

Objective: The purpose of this study was to determine the effect of metaprolol alone and metaprolol plus bromazepam on heart rate and heart rate variability during multi slice computed tomography (MSCT) angiography. Methodology: This was a Double blind randomized controlled trial was conducted at AFIC/NIHD, Rawalpindi, from May 2011 to November 2011. Patients undergoing first MSCT angiography meeting inclusion criteria with heart rates (HR) more than 80 beats/min were included. Patients were randomized in to two groups using random numbers table. Group 1 was administered metaprolol plus placebo while group 2 was administered metaprolol plus bromazepam one hour before the scan. Both groups had scans under strictly similar conditions. HR before and during scan along with heart rate variability (HRV) were recorded. Results: A total of 80 patients were included. Patients mean age was 49 + 13, 57 % were males while 43 % were females. Risk factor profile was similar in both groups. HR reduction in group 1 was 15+ 6.0 and in group 2, was 21+9.0 (p= 0.002). HRV in group 1 was 3.9 + 1.32 and in group 2 was 2.3 + 1.0 (p= 0.003). Group 2 had significantly lower HR and significantly less HRV as compared with group 1. Conclusion: Combination of bromazepam and metaprolol results in significant and further reduction in heart rate and heart rate variability than metaprolol alone. Both drugs can be used together for a better control of heart rate and heart rate variability during MSCT angiography for improving the quality of images. (author)

Wii, Kinect, and Move. Heart Rate, Oxygen Consumption, Energy Expenditure, and Ventilation due to Different Physically Active Video Game Systems in College Students.

Science.gov (United States)

Scheer, Krista S; Siebrant, Sarah M; Brown, Gregory A; Shaw, Brandon S; Shaw, Ina

Nintendo Wii, Sony Playstation Move , and Microsoft XBOX Kinect are home video gaming systems that involve player movement to control on-screen game play. Numerous investigations have demonstrated that playing Wii is moderate physical activity at best, but Move and Kinect have not been as thoroughly investigated. The purpose of this study was to compare heart rate, oxygen consumption, and ventilation while playing the games Wii Boxing, Kinect Boxing, and Move Gladiatorial Combat. Heart rate, oxygen consumption, and ventilation were measured at rest and during a graded exercise test in 10 males and 9 females (19.8 ± 0.33 y, 175.4 ± 2.0 cm, 80.2 ± 7.7 kg,). On another day, in a randomized order, the participants played Wii Boxing, K inect Boxing, and Move Gladiatorial Combat while heart rate, ventilation, and oxygen consumption were measured. There were no differences in heart rate (116.0 ± 18.3 vs. 119.3 ± 17.6 vs. 120.1 ± 17.6 beats/min), oxygen consumption (9.2 ± 3.0 vs. 10.6 ± 2.4 vs. 9.6 ± 2.4 ml/kg/min), or minute ventilation (18.9 ± 5.7 vs. 20.8 ± 8.0 vs. 19.7 ± 6.4 L/min) when playing Wii boxing, Kinect boxing, or Move Gladiatorial Combat (respectively). Playing Nintendo Wii Boxing, XBOX Kinect Boxing, and Sony PlayStation Move Gladiatorial Combat all increase heart rate, oxygen consumption, and ventilation above resting levels but there were no significant differences between gaming systems. Overall, playing a "physically active" home video game system does not meet the minimal threshold for moderate intensity physical activity, regardless of gaming system.

Heating and cooling rates and their effects upon heart rate in the ...

African Journals Online (AJOL)

The heating and cooling rates of adult Chersina angulata were investigated to ascertain whether these tortoises can physiologically alter their rates of heat exchange. In addition, heart rates were recorded to provide an insight into the control of heat exchange. C. angulata heats significantly faster than it cools. Heart rates ...

GLP-1 receptor stimulation depresses heart rate variability and inhibits neurotransmission to cardiac vagal neurons.

Science.gov (United States)

Griffioen, Kathleen J; Wan, Ruiqian; Okun, Eitan; Wang, Xin; Lovett-Barr, Mary Rachael; Li, Yazhou; Mughal, Mohamed R; Mendelowitz, David; Mattson, Mark P

2011-01-01

glucagon-like peptide 1 (GLP-1) is an incretin hormone released from the gut in response to food intake. Whereas GLP-1 acts in the periphery to inhibit glucagon secretion and stimulate insulin release, it also acts in the central nervous system to mediate autonomic control of feeding, body temperature, and cardiovascular function. Because of its role as an incretin hormone, GLP-1 receptor analogs are used as a treatment for type 2 diabetes. Central or peripheral administration of GLP-1 increases blood pressure and heart rate, possibly by activating brainstem autonomic nuclei and increasing vagus nerve activity. However, the mechanism(s) by which GLP-1 receptor stimulation affects cardiovascular function are unknown. We used the long-lasting GLP-1 receptor agonist Exendin-4 (Ex-4) to test the hypothesis that GLP-1 signalling modulates central parasympathetic control of heart rate. using a telemetry system, we assessed heart rate in mice during central Ex-4 administration. Heart rate was increased by both acute and chronic central Ex-4 administration. Spectral analysis indicated that the high frequency and low frequency powers of heart rate variability were diminished by Ex-4 treatment. Finally, Ex-4 decreased both excitatory glutamatergic and inhibitory glycinergic neurotransmission to preganglionic parasympathetic cardiac vagal neurons. these data suggest that central GLP-1 receptor stimulation diminishes parasympathetic modulation of the heart thereby increasing heart rate.

Heart rate awareness in patients with chronic stable heart failure. A multi-center observational study.

LENUS (Irish Health Repository)

Moran, D

2014-08-23

We assessed adherence to European Society of Cardiology heart rate guidelines (i.e. heart rates less than 70bpm) in patients with chronic stable heart failure. We also investigated the percent of patients on target doses of rate controlling drugs.

Reliability of heart rate mobile apps in young healthy adults: exploratory study and research directions

Directory of Open Access Journals (Sweden)

Maria Parpinel

2017-06-01

Full Text Available Background: Recently, a number of smartphone apps appeared that allow for heart rate measurements basing on the photoplethysmography principle. In fact, almost every smartphone now has a camera with flash that could be used for that. Some studies appeared on the reliability of some of those apps, with heterogeneous results. Objectives: The present study aims at adding up evidence in particular during physical activity, by comparing 3 apps on two different platforms (IOs and Android, on a broad range of heart rates. As gold standard, heart rate has been measured with a traditional heart rate monitor. Results: The results suggest that heart rate apps might be used for measuring heart rate for fitness aims for many individuals, but further research is needed to i analyse influence of smartphone features; ii identify personal factors hindering measurements, and iii verify reliability on different measurement sites.

Association between the physical activity and heart rate corrected-QT interval in older adults.

Science.gov (United States)

Michishita, Ryoma; Fukae, Chika; Mihara, Rikako; Ikenaga, Masahiro; Morimura, Kazuhiro; Takeda, Noriko; Yamada, Yosuke; Higaki, Yasuki; Tanaka, Hiroaki; Kiyonaga, Akira

2015-07-01

Increased physical activity can reduce the incidence of cardiovascular disease and the mortality rate. In contrast, a prolonged heart rate corrected-QT (QTc) interval is associated with an increased risk of arrhythmias, sudden cardiac death and coronary artery disease. The present cross-sectional study was designed to clarify the association between the physical activity level and the QTc interval in older adults. The participants included 586 older adults (267 men and 319 women, age 71.2 ± 4.7 years) without a history of cardiovascular disease, who were taking cardioactive drugs. Electrocardiography was recorded with a standard resting 12-lead electrocardiograph, while the QTc interval was calculated according to Hodges' formula. The physical activity level was assessed using a triaxial accelerometer. The participants were divided into four categories, which were defined equally quartile distributions of the QTc interval. After adjusting for age, body mass index, waist circumference and the number of steps, the time spent in inactivity was higher and the time spent in light physical activity was significantly lower in the longest QTc interval group than in the shortest QTc interval group in both sexes (P physical activities among the four groups in either sex. These results suggest that a decreased physical activity level, especially inactivity and light intensity physical activity, were associated with QTc interval in older adults. © 2014 Japan Geriatrics Society.

The mitochondrial uniporter controls fight or flight heart rate increases.

Science.gov (United States)

Wu, Yuejin; Rasmussen, Tyler P; Koval, Olha M; Joiner, Mei-Ling A; Hall, Duane D; Chen, Biyi; Luczak, Elizabeth D; Wang, Qiongling; Rokita, Adam G; Wehrens, Xander H T; Song, Long-Sheng; Anderson, Mark E

2015-01-20

Heart rate increases are a fundamental adaptation to physiological stress, while inappropriate heart rate increases are resistant to current therapies. However, the metabolic mechanisms driving heart rate acceleration in cardiac pacemaker cells remain incompletely understood. The mitochondrial calcium uniporter (MCU) facilitates calcium entry into the mitochondrial matrix to stimulate metabolism. We developed mice with myocardial MCU inhibition by transgenic expression of a dominant-negative (DN) MCU. Here, we show that DN-MCU mice had normal resting heart rates but were incapable of physiological fight or flight heart rate acceleration. We found that MCU function was essential for rapidly increasing mitochondrial calcium in pacemaker cells and that MCU-enhanced oxidative phoshorylation was required to accelerate reloading of an intracellular calcium compartment before each heartbeat. Our findings show that MCU is necessary for complete physiological heart rate acceleration and suggest that MCU inhibition could reduce inappropriate heart rate increases without affecting resting heart rate.

Effects of age and physical activity on the autonomic control of heart rate in healthy men

Directory of Open Access Journals (Sweden)

R.C. Melo

2005-09-01

Full Text Available The effects of the aging process and an active life-style on the autonomic control of heart rate (HR were investigated in nine young sedentary (YS, 23 ± 2.4 years, 16 young active (YA, 22 ± 2.1 years, 8 older sedentary (OS, 63 ± 2.4 years and 8 older active (OA, 61 ± 1.1 years healthy men. Electrocardiogram was continuously recorded for 15 min at rest and for 4 min in the deep breathing test, with a breath rate of 5 to 6 cycles/min in the supine position. Resting HR and RR intervals were analyzed by time (RMSSD index and frequency domain methods. The power spectral components are reported in normalized units (nu at low (LF and high (HF frequency, and as the LF/HF ratio. The deep breathing test was analyzed by the respiratory sinus arrhythmia indices: expiration/inspiration ratio (E/I and inspiration-expiration difference (deltaIE. The active groups had lower HR and higher RMSSD index than the sedentary groups (life-style condition: sedentary vs active, P < 0.05. The older groups showed lower HFnu, higher LFnu and higher LF/HF ratio than the young groups (aging effect: young vs older, P < 0.05. The OS group had a lower E/I ratio (1.16 and deltaIE (9.7 bpm than the other groups studied (YS: 1.38, 22.4 bpm; YA: 1.40, 21.3 bpm; OA: 1.38, 18.5 bpm. The interaction between aging and life-style effects had a P < 0.05. These results suggest that aging reduces HR variability. However, regular physical activity positively affects vagal activity on the heart and consequently attenuates the effects of aging in the autonomic control of HR.

Does a variation in self-reported physical activity reflect variation in objectively measured physical activity, resting heart rate, and physical fitness? Results from the Tromso study

DEFF Research Database (Denmark)

Emaus, Aina; Degerstrøm, Jorid; Wilsgaard, Tom

2010-01-01

AIMS: To study the association between self-reported physical activity (PA) and objectively measured PA, resting heart rate, and physical fitness. METHODS: During 2007-08, 5017 men and 5607 women aged 30-69 years attended the sixth survey of the Tromsø study. Self-reported PA during leisure......-time and work were assessed and resting heart rate was measured. In a sub-study, the activity study, PA (Actigraph LLC) and physical fitness (VO₂(max)) were objectively measured among 313 healthy men and women aged 40-44 years. RESULTS: Self-reported leisure PA was significantly correlated with VO₂(max) (ml...... women than men met the international recommendations of 10,000 step counts/day (27% vs. 22%) and the recommendation of at least 30 minutes/day of moderate-to-vigorous intensities (30% vs. 22 %). CONCLUSIONS: The Tromsø physical activity questionnaire has acceptable validity and provides valid estimates...

Arduino-based noise robust online heart-rate detection.

Science.gov (United States)

Das, Sangita; Pal, Saurabh; Mitra, Madhuchhanda

2017-04-01

This paper introduces a noise robust real time heart rate detection system from electrocardiogram (ECG) data. An online data acquisition system is developed to collect ECG signals from human subjects. Heart rate is detected using window-based autocorrelation peak localisation technique. A low-cost Arduino UNO board is used to implement the complete automated process. The performance of the system is compared with PC-based heart rate detection technique. Accuracy of the system is validated through simulated noisy ECG data with various levels of signal to noise ratio (SNR). The mean percentage error of detected heart rate is found to be 0.72% for the noisy database with five different noise levels.

An open-source LabVIEW application toolkit for phasic heart rate analysis in psychophysiological research.

Science.gov (United States)

Duley, Aaron R; Janelle, Christopher M; Coombes, Stephen A

2004-11-01

The cardiovascular system has been extensively measured in a variety of research and clinical domains. Despite technological and methodological advances in cardiovascular science, the analysis and evaluation of phasic changes in heart rate persists as a way to assess numerous psychological concomitants. Some researchers, however, have pointed to constraints on data analysis when evaluating cardiac activity indexed by heart rate or heart period. Thus, an off-line application toolkit for heart rate analysis is presented. The program, written with National Instruments' LabVIEW, incorporates a variety of tools for off-line extraction and analysis of heart rate data. Current methods and issues concerning heart rate analysis are highlighted, and how the toolkit provides a flexible environment to ameliorate common problems that typically lead to trial rejection is discussed. Source code for this program may be downloaded from the Psychonomic Society Web archive at www.psychonomic.org/archive/.

Wii, Kinect, and Move. Heart Rate, Oxygen Consumption, Energy Expenditure, and Ventilation due to Different Physically Active Video Game Systems in College Students

OpenAIRE

SCHEER, KRISTA S.; SIEBRANT, SARAH M.; BROWN, GREGORY A.; SHAW, BRANDON S.; SHAW, INA

2014-01-01

Nintendo Wii, Sony Playstation Move, and Microsoft XBOX Kinect are home video gaming systems that involve player movement to control on-screen game play. Numerous investigations have demonstrated that playing Wii is moderate physical activity at best, but Move and Kinect have not been as thoroughly investigated. The purpose of this study was to compare heart rate, oxygen consumption, and ventilation while playing the games Wii Boxing, Kinect Boxing, and Move Gladiatorial Combat. Heart rate, o...

Increased heart rate variability in mice overexpressing the Cu/Zn superoxide dismutase.

Science.gov (United States)

Thireau, Jérôme; Poisson, Denise; Zhang, Bei Li; Gillet, Ludovic; Le Pécheur, Marie; Andres, Christian; London, Jacqueline; Babuty, Dominique

2008-08-15

Cu/Zn superoxide dismutase (SOD1) is implicated in various pathological conditions including Down's syndrome, neurodegenerative diseases, and afflictions of the autonomic nervous system (ANS). To assess the SOD1 contribution to ANS dysfunction, especially its influence on cardiac regulation, we studied the heart rate variability (HRV) and cardiac arrhythmias in conscious 12-month-old male and female transgenic mice for the human SOD1 gene (TghSOD1). TghSOD1 mice presented heart rate reduction as compared with control FVB/N individuals. All HRV parameters reflecting parasympathetic activity were increased in TghSOD1. Pharmacological studies confirmed that the parasympathetic tone was exacerbated and the sympathetic pathway was functional in TghSOD1 mice. A high frequency of atrioventricular block and premature ventricular contractions was observed in TghSOD1. By biochemical assays we found that SOD1 activities were multiplied by 9 and 4 respectively in the heart and brainstem of transgenic mice. A twofold decrease in cholinesterase activity was observed in the heart but not in the brainstem. We demonstrate that SOD1 overexpression induces an ANS dysfunction by an exacerbated vagal tone that may be related to impaired cardiac activity of the cholinesterases and may explain the high occurrence of arrhythmias.

Heart rate variability interventions for concussion and rehabilitation

OpenAIRE

Conder, Robert L.; Conder, Alanna A.

2014-01-01

The study of Heart Rate Variability (HRV) has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain). It is well-established that lack of heart rate variability implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal heart rate variability has been associated ...

Increasing T-type calcium channel activity by β-adrenergic stimulation contributes to β-adrenergic regulation of heart rates.

Science.gov (United States)

Li, Yingxin; Zhang, Xiaoxiao; Zhang, Chen; Zhang, Xiaoying; Li, Ying; Qi, Zhao; Szeto, Christopher; Tang, Mingxin; Peng, Yizhi; Molkentin, Jeffery D; Houser, Steven R; Xie, Mingxing; Chen, Xiongwen

2018-04-01

Cav3.1 T-type Ca 2+ channel current (I Ca-T ) contributes to heart rate genesis but is not known to contribute to heart rate regulation by the sympathetic/β-adrenergic system (SAS). We show that the loss of Cav3.1 makes the beating rates of the heart in vivo and perfused hearts ex vivo, as well as sinoatrial node cells, less sensitive to β-adrenergic stimulation; it also renders less conduction acceleration through the atrioventricular node by β-adrenergic stimulation. Increasing Cav3.1 in cardiomyocytes has the opposite effects. I Ca-T in sinoatrial nodal cells can be upregulated by β-adrenergic stimulation. The results of the present study add a new contribution to heart rate regulation by the SAS system and provide potential new mechanisms for the dysregulation of heart rate and conduction by the SAS in the heart. T-type Ca 2+ channel can be a target for heart disease treatments that aim to slow down the heart rate ABSTRACT: Cav3.1 (α 1G ) T-type Ca 2+ channel (TTCC) is expressed in mouse sinoatrial node cells (SANCs) and atrioventricular (AV) nodal cells and contributes to heart rate (HR) genesis and AV conduction. However, its role in HR regulation and AV conduction acceleration by the β-adrenergic system (SAS) is unclear. In the present study, L- (I Ca-L ) and T-type (I Ca-T ) Ca 2+ currents were recorded in SANCs from Cav3.1 transgenic (TG) and knockout (KO), and control mice. I Ca-T was absent in KO SANCs but enhanced in TG SANCs. In anaesthetized animals, different doses of isoproterenol (ISO) were infused via the jugular vein and the HR was recorded. The EC 50 of the HR response to ISO was lower in TG mice but higher in KO mice, and the maximal percentage of HR increase by ISO was greater in TG mice but less in KO mice. In Langendorff-perfused hearts, ISO increased HR and shortened PR intervals to a greater extent in TG but to a less extent in KO hearts. KO SANCs had significantly slower spontaneous beating rates than control SANCs before and after

Music close to one's heart: heart rate variability with music, diagnostic with e-bra and smartphone

Science.gov (United States)

Hegde, Shantala; Kumar, Prashanth S.; Rai, Pratyush; Mathur, Gyanesh N.; Varadan, Vijay K.

2012-04-01

Music is a powerful elicitor of emotions. Emotions evoked by music, through autonomic correlates have been shown to cause significant modulation of parameters like heart rate and blood pressure. Consequently, Heart Rate Variability (HRV) analysis can be a powerful tool to explore evidence based therapeutic functions of music and conduct empirical studies on effect of musical emotion on heart function. However, there are limitations with current studies. HRV analysis has produced variable results to different emotions evoked via music, owing to variability in the methodology and the nature of music chosen. Therefore, a pragmatic understanding of HRV correlates of musical emotion in individuals listening to specifically chosen music whilst carrying out day to day routine activities is needed. In the present study, we aim to study HRV as a single case study, using an e-bra with nano-sensors to record heart rate in real time. The e-bra developed previously, has several salient features that make it conducive for this study- fully integrated garment, dry electrodes for easy use and unrestricted mobility. The study considers two experimental conditions:- First, HRV will be recorded when there is no music in the background and second, when music chosen by the researcher and by the subject is playing in the background.

Facial Vibrotactile Stimulation Activates the Parasympathetic Nervous System: Study of Salivary Secretion, Heart Rate, Pupillary Reflex, and Functional Near-Infrared Spectroscopy Activity

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Hisao Hiraba

2014-01-01

Full Text Available We previously found that the greatest salivation response in healthy human subjects is produced by facial vibrotactile stimulation of 89 Hz frequency with 1.9 μm amplitude (89 Hz-S, as reported by Hiraba et al. (2012, 20011, and 2008. We assessed relationships between the blood flow to brain via functional near-infrared spectroscopy (fNIRS in the frontal cortex and autonomic parameters. We used the heart rate (HRV: heart rate variability analysis in RR intervals, pupil reflex, and salivation as parameters, but the interrelation between each parameter and fNIRS measures remains unknown. We were to investigate the relationship in response to established paradigms using simultaneously each parameter-fNIRS recording in healthy human subjects. Analysis of fNIRS was examined by a comparison of various values between before and after various stimuli (89 Hz-S, 114 Hz-S, listen to classic music, and “Ahh” vocalization. We confirmed that vibrotactile stimulation (89 Hz of the parotid glands led to the greatest salivation, greatest increase in heart rate variability, and the most constricted pupils. Furthermore, there were almost no detectable differences between fNIRS during 89 Hz-S and fNIRS during listening to classical music of fans. Thus, vibrotactile stimulation of 89 Hz seems to evoke parasympathetic activity.

Heart Rate Monitoring in Team Sports—A Conceptual Framework for Contextualizing Heart Rate Measures for Training and Recovery Prescription

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Christoph Schneider

2018-05-01

Full Text Available A comprehensive monitoring of fitness, fatigue, and performance is crucial for understanding an athlete's individual responses to training to optimize the scheduling of training and recovery strategies. Resting and exercise-related heart rate measures have received growing interest in recent decades and are considered potentially useful within multivariate response monitoring, as they provide non-invasive and time-efficient insights into the status of the autonomic nervous system (ANS and aerobic fitness. In team sports, the practical implementation of athlete monitoring systems poses a particular challenge due to the complex and multidimensional structure of game demands and player and team performance, as well as logistic reasons, such as the typically large number of players and busy training and competition schedules. In this regard, exercise-related heart rate measures are likely the most applicable markers, as they can be routinely assessed during warm-ups using short (3–5 min submaximal exercise protocols for an entire squad with common chest strap-based team monitoring devices. However, a comprehensive and meaningful monitoring of the training process requires the accurate separation of various types of responses, such as strain, recovery, and adaptation, which may all affect heart rate measures. Therefore, additional information on the training context (such as the training phase, training load, and intensity distribution combined with multivariate analysis, which includes markers of (perceived wellness and fatigue, should be considered when interpreting changes in heart rate indices. The aim of this article is to outline current limitations of heart rate monitoring, discuss methodological considerations of univariate and multivariate approaches, illustrate the influence of different analytical concepts on assessing meaningful changes in heart rate responses, and provide case examples for contextualizing heart rate measures using

Heart Rate Monitoring in Team Sports-A Conceptual Framework for Contextualizing Heart Rate Measures for Training and Recovery Prescription.

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Schneider, Christoph; Hanakam, Florian; Wiewelhove, Thimo; Döweling, Alexander; Kellmann, Michael; Meyer, Tim; Pfeiffer, Mark; Ferrauti, Alexander

2018-01-01

A comprehensive monitoring of fitness, fatigue, and performance is crucial for understanding an athlete's individual responses to training to optimize the scheduling of training and recovery strategies. Resting and exercise-related heart rate measures have received growing interest in recent decades and are considered potentially useful within multivariate response monitoring, as they provide non-invasive and time-efficient insights into the status of the autonomic nervous system (ANS) and aerobic fitness. In team sports, the practical implementation of athlete monitoring systems poses a particular challenge due to the complex and multidimensional structure of game demands and player and team performance, as well as logistic reasons, such as the typically large number of players and busy training and competition schedules. In this regard, exercise-related heart rate measures are likely the most applicable markers, as they can be routinely assessed during warm-ups using short (3-5 min) submaximal exercise protocols for an entire squad with common chest strap-based team monitoring devices. However, a comprehensive and meaningful monitoring of the training process requires the accurate separation of various types of responses, such as strain, recovery, and adaptation, which may all affect heart rate measures. Therefore, additional information on the training context (such as the training phase, training load, and intensity distribution) combined with multivariate analysis, which includes markers of (perceived) wellness and fatigue, should be considered when interpreting changes in heart rate indices. The aim of this article is to outline current limitations of heart rate monitoring, discuss methodological considerations of univariate and multivariate approaches, illustrate the influence of different analytical concepts on assessing meaningful changes in heart rate responses, and provide case examples for contextualizing heart rate measures using simple heuristics. To

Influence of different characteristics of sport on heart rate recovery in elite athletes

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Anđić Radovan

2016-01-01

Full Text Available Introduction: One of the benefits of regular physical activity is lower resting heart rate and its faster recovery after maximal exercise test, as a result of a stronger parasympatic (vagal tone. Heart rate recovery is used as reliable parameter for prescription of the training program and also in prognostic purposes as a parameter of risk for developing cardiovascular diseases. Aim: The purpose of this study is to show significant differences in heart rate recovery after maximal exercise test and resting heart rate among different groups of elite athletes. Material and Methods: This study subjected 575 adult (23.1 ± 4.3 years, male athletes divided into four sport groups: skill, power, mixed and endurance. Every subject performed progressive, maximal cardiopulmonary exercise test on a treadmill. Heart rate recovery in first (ΔHRR1 and third (ΔHRR3 minute was calculated as a difference of maximal heart rate and heart rate in the first and the third minute after cessation of exercise, respectively. Results: Compared to skill, power and mixed group (62.9 ± 11.4; 61.5 ± 10.0; 59.9 ± 10.4 min-1 respectively, significantly lower values od resting heart rate are recorded in the endurance group (56.2 ± 10.6 min-1 (p = 0,05. Also, ΔHRR1 was significantly higher in the endurance group (33.5 ±14.3 min-1 compared to skill, power and mixed group (24.3 ± 10.9; 25.5 ± 11.2; 27.8 ± 15.6 min-1 respectively (p = 0,05. Values od ΔHRR3 were significantly higher in power, mixed and endurance groups (74.8 ± 14.3; 79.5 ± 12.7; 79.4 ± 12.6 min-1 respectively compared to skill group (67.3±16.1 min-1 (p = 0,05. Conclusion: Training endurance group of sports has the most contribution to lower resting heart rate and faster recovery of heart rate in the first minute after exercising, due to dominant parasympatic tone.

Heart rate measurement based on face video sequence

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Xu, Fang; Zhou, Qin-Wu; Wu, Peng; Chen, Xing; Yang, Xiaofeng; Yan, Hong-jian

2015-03-01

This paper proposes a new non-contact heart rate measurement method based on photoplethysmography (PPG) theory. With this method we can measure heart rate remotely with a camera and ambient light. We collected video sequences of subjects, and detected remote PPG signals through video sequences. Remote PPG signals were analyzed with two methods, Blind Source Separation Technology (BSST) and Cross Spectral Power Technology (CSPT). BSST is a commonly used method, and CSPT is used for the first time in the study of remote PPG signals in this paper. Both of the methods can acquire heart rate, but compared with BSST, CSPT has clearer physical meaning, and the computational complexity of CSPT is lower than that of BSST. Our work shows that heart rates detected by CSPT method have good consistency with the heart rates measured by a finger clip oximeter. With good accuracy and low computational complexity, the CSPT method has a good prospect for the application in the field of home medical devices and mobile health devices.

Heart rate response to hypoxic exercise

DEFF Research Database (Denmark)

Lundby, C; Møller, P; Kanstrup, I L

2001-01-01

progressively decreased the maximal heart rate from day 1 and onwards; also, hypoxia by itself increased plasma noradrenaline levels after maximal exercise. Domperidone further increased maximal noradrenaline concentrations, but had no effect on maximal heart rate. On each study day at altitude, oxygen......This study examined the effects of dopamine D(2)-receptor blockade on the early decrease in maximal heart rate at high altitude (4559 m). We also attempted to clarify the time-dependent component of this reduction and the extent to which it is reversed by oxygen breathing. Twelve subjects performed...... two consecutive maximal exercise tests, without and with oxygen supplementation respectively, at sea level and after 1, 3 and 5 days at altitude. On each study day, domperidone (30 mg; n=6) or no medication (n=6) was given 1 h before the first exercise session. Compared with sea level, hypoxia...

Visualization of heart rate variability of long-term heart transplant patient by transition networks: a case report

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Joanna eWdowczyk

2016-03-01

Full Text Available We present a heart transplant patient at his 17th year of uncomplicated follow-up. Within a frame of routine check out several tests were performed. With such a long and uneventful follow-up some degree of graft reinnervation could be anticipated. However, the patient's electrocardiogram and exercise parameters seemed largely inconclusive in this regard. The exercise heart rate dynamics were suggestive of only mild, if any parasympathetic reinnervation of the graft with persisting sympathetic activation. On the other hand, traditional heart rate variability (HRV indices were inadequately high, due to erratic rhythm resulting from interference of the persisting recipient sinus node or nonconducted atrial parasystole. New tools, originated from network representation of time series, by visualization short-term dynamical patterns, provided a method to discern HRV increase due to reinnervation from other reasons.

Longitudinal Associations of Leptin and Adiponectin with Heart Rate Variability in Children

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Roos Van De Wielle

2017-07-01

Full Text Available For early prevention of cardiovascular disease, early detection and risk factor insights are necessary. The autonomic balance reflects cardiovascular risk and can be measured by heart rate variability (HRV. Therefore, our purpose is to examine associations between HRV and the energy-related biomarkers leptin and adiponectin in children. Participants of this study were Belgian children recruited for the longitudinal ChiBS study (year 2010–2012. HRV was measured and fasting blood samples were taken in 249 children at baseline (4.4–11.0 y and 223 children at follow-up (6.7–12.2 y. Cross-sectional and longitudinal linear regression analyses were separated by sex and adjusted for age, socio-economic status, body fat%, negative emotions, puberty, and mean heart rate. Leptin was a negative cross-sectional and longitudinal predictor of parasympathetic activity in boys; while leptin in girls was cross-sectionally associated with higher LF and LF/HF suggesting sympathetic predominance. Adiponectin was a negative cross-sectional and longitudinal predictor of parasympathetic activity in boys; but when adjusting for mean heart rate, this effect disappeared and adiponectin was a positive cross-sectional and longitudinal predictor of parasympathetic activity in girls. These results stress the importance of considering sex differences and adjustment for heart rate in testing HRV predictors. Leptin seemed disadvantageous for the autonomic balance, while adiponectin seemed advantageous for the autonomic balance in girls only. More research is needed to see whether leptin and adiponectin are interesting in cardiovascular screening/prevention or in determining the cardiovascular gain during weight loss follow-up.

Comparison of energy expenditure by the doubly labeled water technique with energy intake, heart rate, and activity recording in man

International Nuclear Information System (INIS)

Schulz, S.; Westerterp, K.R.; Brueck, K.

1989-01-01

Average daily energy expenditure determined by the doubly labeled water technique (dlwEE) was compared in six subjects (aged 20-30 y) over 2 wk under usual living conditions; average food energy intake and energy expenditure estimated from individual diary records of physical activity. In addition, energy expenditure was estimated from 24-h heart rate recordings carried out on two randomly chosen days of the 2-wk period. The group means of the dlwEE were 1.94 +/- 0.24 (means +/- SD) times larger than resting metabolic rate (= 1.94 met) and nearly identical to the average daily energy intake (1.93 +/- 0.23 met). Energy expenditure estimated from the diaries of activity and from the 24-h heart rate recording varied between 1.67 and 2.24 met depending on the calculation procedure. The dlwEE (1.94 +/- 0.24 met) is much higher than that recently determined for sedentary people (1.25 met) and thus explains that young students may achieve body weight balance with a relatively high daily food energy intake

The heart field effect: Synchronization of healer-subject heart rates in energy therapy.

Science.gov (United States)

Bair, Christine Caldwell

2008-01-01

Recent health research has focused on subtle energy and vibrational frequency as key components of health and healing. In particular, intentional direction of bioenergy is receiving increasing scientific attention. This study investigates the effect of the healer's electromagnetic (EM) heart field upon subjects during energy healing as measured by synchronization of heart rates and scores on a Subjective Units of Distress (SUD) scale and a Profile of Mood States (POMS) inventory. A nonequivalent pretest-posttest design was used based on heart rate comparisons between healer and subject and correlated with pre-and posttest SUD and POMS scores. Subjects included those who sat within the 3- to 4-foot "strong" range of the independent variable, the healer's heart field, while performing self-application of WHEE (the wholistic hybrid derived from EMDR [eye movement desensitization and reprocessing], and EFT [emotional freedom technique]), a meridian-based tapping technique (n=50); and those who performed the same process beyond the 15- to 18-foot range of the healer's EM heart field (n=41). The dependent variables were heart rate, SUD, and POMS inventory. All subjects completed these measures within 1 hour. Study results showed statistically significant heart-rate synchronization with the intervention population. In addition, SUD and POMS scores demonstrated considerably more improvement than in the control population, indicating additional benefit beyond the meridian-based therapies, such as WHEE, alone. Additional findings and future research recommendations are presented in this article.

Learning by Heart: Students Use Heart Rate Patterns To Identify Nervous System Imbalances.

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Ackerly, Spafford C.

2001-01-01

Introduces a science unit on heart rate variability (HVR) patterns. Uses spectral analysis to determine the effects of environmental stimulants such as music and emotional stress on heart rate. Observes relaxation techniques and their effects on the autonomous nervous system. (Contains 12 references.) (YDS)

[Resonance hypothesis of heart rate variability origin].

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Sheĭkh-Zade, Iu R; Mukhambetaliev, G Kh; Cherednik, I L

2009-09-01

A hypothesis is advanced of the heart rate variability being subjected to beat-to-beat regulation of cardiac cycle duration in order to ensure the resonance interaction between respiratory and own fluctuation of the arterial system volume for minimization of power expenses of cardiorespiratory system. Myogenic, parasympathetic and sympathetic machanisms of heart rate variability are described.

Hopfield neural network and optical fiber sensor as intelligent heart rate monitor

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Mutter, Kussay Nugamesh

2018-01-01

This paper presents a design and fabrication of an intelligent fiber-optic sensor used for examining and monitoring heart rate activity. It is found in the literature that the use of fiber sensors as heart rate sensor is widely studied. However, the use of smart sensors based on Hopfield neural networks is very low. In this work, the sensor is a three fibers without cladding of about 1 cm, fed by laser light of 1550 nm of wavelength. The sensing portions are mounted with a micro sensitive diaphragm to transfer the pulse pressure on the left radial wrist. The influenced light intensity will be detected by a three photodetectors as inputs into the Hopfield neural network algorithm. The latter is a singlelayer auto-associative memory structure with a same input and output layers. The prior training weights are stored in the net memory for the standard recorded normal heart rate signals. The sensors' heads work on the reflection intensity basis. The novelty here is that the sensor uses a pulse pressure and Hopfield neural network in an integrity approach. The results showed a significant output measurements of heart rate and counting with a plausible error rate.

Attachment Status Affects Heart Rate Responses to Experimental Ostracism in Inpatients with Depression.

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Jannika De Rubeis

Full Text Available Depression is assumed to be both a risk factor for rejection and a result of it, and as such constitutes an important factor in rejection research. Attachment theory has been applied to understand psychological disorders, such as depression, and can explain individual differences in responses to rejection. Research on autonomic nervous system activity to rejection experiences has been contradictory, with opposing strings of argumentation (activating vs. numbing. We investigated autonomic nervous system-mediated peripheral physiological responses (heart rate to experimentally manipulated ostracism (Cyberball in 97 depressed patients with organized (n = 52 and disorganized attachment status (n = 45. Controlling for baseline mean heart rate levels, depressed patients with disorganized attachment status responded to ostracism with significantly higher increases in heart rate than depressed patients with organized attachment status (p = .029; ηp2 = .051. These results suggest that attachment status may be a useful indicator of autonomic responses to perceived social threat, which in turn may affect the therapeutic process and the patient-therapist relationship.

Heart rate variability recovery after a skyrunning marathon and correlates of performance

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Michaela Mertová

2017-12-01

Full Text Available Background: It is well known that vigorous physical activity induces functional changes in cardiac autonomic nervous system (ANS activity that is sustained several hours after exercise. However, data related to ANS recovery after more extreme endurance events, such as skyrunning marathons, are still lacking. Objective: The aims of this prospective cohort study were firstly, to determine the ANS response to a SkyMarathon, and secondly, to examine correlates of run performance. Methods: Ten male skyrunners aged 37.2 ± 9.2 years were recruited. The race was performed at a mean intensity 85.4 ± 3.7% of heart rate reserve, and lasted for 338 ± 38 min. Morning supine heart rate variability was measured at 10, 2 and 1 days before race, on the race day, at 5 min intervals for 30 min immediately post-race and then at 5 h and 30 h post. High-frequency power (HF, 0.15-0.50 Hz, low-frequency power (LF, 0.05-0.15 Hz, and square root of the mean of the squares of the successive differences (RMSSD were calculated and transformed by natural logarithm (Ln. Results: Sympathovagal balance (Ln LF/HF was most likely increased above baseline during the 30 min post-race and returned to baseline by 5 h. Vagal activity (Ln RMSSD and Ln HF was most likely decreased below baseline during the 30 min post-race and 5 h of post-race, and recovered to baseline by 30 h. Race time correlated with resting heart rate (r = .81, body mass index (r = .73, maximal power output (r = -.70, and maximal oxygen uptake (r = -.61. Conclusions: The SkyMarathon elicited disturbances in ANS activity, with relative sympathetic activity increased up to 5 h post-race and vagal activity recovering by 30 h. Resting heart rate, body mass index, maximal power output, and maximal oxygen uptake were associated with SkyMarathon performance prediction.

Accuracy of Heart Rate Watches: Implications for Weight Management.

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Matthew P Wallen

Full Text Available Wrist-worn monitors claim to provide accurate measures of heart rate and energy expenditure. People wishing to lose weight use these devices to monitor energy balance, however the accuracy of these devices to measure such parameters has not been established.To determine the accuracy of four wrist-worn devices (Apple Watch, Fitbit Charge HR, Samsung Gear S and Mio Alpha to measure heart rate and energy expenditure at rest and during exercise.Twenty-two healthy volunteers (50% female; aged 24 ± 5.6 years completed ~1-hr protocols involving supine and seated rest, walking and running on a treadmill and cycling on an ergometer. Data from the devices collected during the protocol were compared with reference methods: electrocardiography (heart rate and indirect calorimetry (energy expenditure.None of the devices performed significantly better overall, however heart rate was consistently more accurate than energy expenditure across all four devices. Correlations between the devices and reference methods were moderate to strong for heart rate (0.67-0.95 [0.35 to 0.98] and weak to strong for energy expenditure (0.16-0.86 [-0.25 to 0.95]. All devices underestimated both outcomes compared to reference methods. The percentage error for heart rate was small across the devices (range: 1-9% but greater for energy expenditure (9-43%. Similarly, limits of agreement were considerably narrower for heart rate (ranging from -27.3 to 13.1 bpm than energy expenditure (ranging from -266.7 to 65.7 kcals across devices.These devices accurately measure heart rate. However, estimates of energy expenditure are poor and would have implications for people using these devices for weight loss.

Accuracy of Heart Rate Watches: Implications for Weight Management.

Science.gov (United States)

Wallen, Matthew P; Gomersall, Sjaan R; Keating, Shelley E; Wisløff, Ulrik; Coombes, Jeff S

2016-01-01

Wrist-worn monitors claim to provide accurate measures of heart rate and energy expenditure. People wishing to lose weight use these devices to monitor energy balance, however the accuracy of these devices to measure such parameters has not been established. To determine the accuracy of four wrist-worn devices (Apple Watch, Fitbit Charge HR, Samsung Gear S and Mio Alpha) to measure heart rate and energy expenditure at rest and during exercise. Twenty-two healthy volunteers (50% female; aged 24 ± 5.6 years) completed ~1-hr protocols involving supine and seated rest, walking and running on a treadmill and cycling on an ergometer. Data from the devices collected during the protocol were compared with reference methods: electrocardiography (heart rate) and indirect calorimetry (energy expenditure). None of the devices performed significantly better overall, however heart rate was consistently more accurate than energy expenditure across all four devices. Correlations between the devices and reference methods were moderate to strong for heart rate (0.67-0.95 [0.35 to 0.98]) and weak to strong for energy expenditure (0.16-0.86 [-0.25 to 0.95]). All devices underestimated both outcomes compared to reference methods. The percentage error for heart rate was small across the devices (range: 1-9%) but greater for energy expenditure (9-43%). Similarly, limits of agreement were considerably narrower for heart rate (ranging from -27.3 to 13.1 bpm) than energy expenditure (ranging from -266.7 to 65.7 kcals) across devices. These devices accurately measure heart rate. However, estimates of energy expenditure are poor and would have implications for people using these devices for weight loss.

Universal design of a microcontroller and IoT system to detect the heart rate

Science.gov (United States)

Uwamahoro, Raphael; Mushikiwabeza, Alexie; Minani, Gerard; Mohan Murari, Bhaskar

2017-11-01

Heart rate analysis provides vital information of the present condition of the human body. It helps medical professionals in diagnosis of various malfunctions of the body. The limitation of vision impaired and blind people to access medical devices cause a considerable loss of life. In this paper, we intended to develop a heart rate detection system that is usable for people with normal and abnormal vision. The system is based on a non-invasive method of measuring the variation of the tissue blood flow rate by means of a photo transmitter and detector through fingertip known as photoplethysmography (PPG). The signal detected is firstly passed through active low pass filter and then amplified by a two stages high gain amplifier. The amplified signal is feed into the microcontroller to calculate the heart rate and displays the heart beat via sound systems and Liquid Crystal Display (LCD). To distinguish arrhythmia, normal heart rate and abnormal working conditions of the system, recognition is provided in different sounds, LCD readings and Light Emitting Diodes (LED).

Effect of partial sports massage on blood pressure and heart rate

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T.D. Pystupa

2013-12-01

Full Text Available With the growing popularity and demand for different types of massages (including sports is a growing need for research on specific forms. There is also a need to study the advantages and effects on various body functions. The objective was to study the effect of partial sports massage on blood pressure and heart rate in both men and women. Material and methods. Research has been extended 80 healthy men and women are physically active (age 20-25 years. Blood pressure and heart rate were made on the left arm automatic digital device (model HEM - 907. The device is intended to measure blood pressure. It is established that it is possible to verify the existing beliefs. This promotes more efficient use of massage therapy. Conclusions . Sports massage has an effect on hemodynamic changes, the increase (decrease in blood pressure acceleration (deceleration of the heart rate. It depends on what part of the body exposed to the massage procedure.

Simultaneous measurement of instantaneous heart rate and chest wall plethysmography in short-term, metronome guided heart rate variability studies: suitability for assessment of autonomic dysfunction.

Science.gov (United States)

Perring, S; Jones, E

2003-08-01

Instantaneous heart rate and chest wall motion were measured using a 3-lead ECG and an air pressure chest wall plethysmography system. Chest wall plethysmography traces were found to accurately represent the breathing pattern as measured by spirometry (average correlation coefficient 0.944); though no attempt was made to calibrate plethysmography voltage output to tidal volume. Simultaneous measurements of heart rate and chest wall motion were made for short periods under metronome guided breathing at 6 breaths per minute. The average peak to trough heart rate change per breath cycle (AVEMAX) and maximum correlation between heart rate and breathing cycle (HRBRCORR) were measured. Studies of 44 normal volunteers indicated clear inverse correlation of heart rate variability parameters with age (AVEMAX R = -0.502, P < 0.001) but no significant change in HRBRCORR with age (R = -0.115). Comparison of normal volunteers with diabetics with no history of symptoms associated with autonomic failure indicated significant lower heart rate variability in diabetics (P = 0.005 for AVEMAX) and significantly worse correlation between heart rate and breathing (P < 0.001 for HRBRCORR). Simultaneous measurement of heart rate and breathing offers the possibility of more sensitive diagnosis of autonomic failure in a simple bedside test and gives further insight into the nature of cardio-ventilatory coupling.

Arterial wall mechanics as a function of heart rate: role of vascular smooth muscle

International Nuclear Information System (INIS)

Salvucci, Fernando Pablo; Schiavone, Jonathan; Craiem, Damian; Barra, Juan Gabriel

2007-01-01

Vascular wall viscoelasticity can be evaluated using a first-order lumped model. This model consists of a spring with elastic constant E and a dashpot with viscous constant η. More importantly, this viscoelastic model can be fitted in-vivo measuring arterial pressure and diameter. The aim of this work is to analyze the influence of heart rate over E and η. In two anesthetized sheep, diameter in thoracic aorta and intravascular pressure has been registered. The right atrium was connected to a programmable stimulator through a pair of pace-maker wires to produce changes in stimulation heart rate (HR) from 80 to 160 bpm. Additionally, local activation of vascular smooth muscle was induced with phenylephrine. After converting pressure and diameter signals into stress and strain respectively, E y η were calculated in control state and during muscle activation. The elastic modulus E did not present significant changes with heart rate. The viscous modulus η decreased 49% with a two-fold acceleration in heart rate from 80 to 160 bpm. However, the product η HR remained stable. The viscous modulus η increased 39% with smooth muscle activation. No significant pressure changes were registered during the experiment. The contractile action of vascular smooth muscle could contribute to increasing arterial wall viscosity. The decrease of η when HR increased might be related to smooth muscle relaxation mediated by endothelium activity, which was stimulated by flow increase. We conclude that HR can modulate arterial wall viscoelasticity through endothelium-dependent mechanisms

Playing a violent television game affects heart rate variability.

Science.gov (United States)

Ivarsson, Malena; Anderson, Martin; Akerstedt, Torbjörn; Lindblad, Frank

2009-01-01

To investigate how playing a violent/nonviolent television game during the evening affects sympathetic and parasympathetic reactions during and after playing as well as sleep quality during the night after playing. In total, 19 boys, 12-15 years of age, played television games on two occasions in their homes and participated once without gaming. Heart rate, heart rate variability (HRV) and physical activity were measured during gaming/participating and the night to follow using a portable combined heart rate and movement sensor. A sleep diary and questionnaires about gaming experiences and session-specific experiences were filled in. Criteria for Selection of Games: Violent game involves/rewards direct physical violence (no handguns) against another person, and nonviolent game involves/rewards no violence; same game design ('third-person game'); conducted in the same manner; no differences concerning motor activity; similar sound and light effects; no sexual content, violence against women or racial overtones. During violent (vs. nonviolent) gaming, there was significantly higher activity of the very low frequency component of the HRV and total power. During the night after playing, very low frequency, low frequency and high frequency components were significantly higher during the violent (vs. nonviolent) condition, just as total power. There were no significant differences between the three conditions (violent/nonviolent/no gaming) with respect to an index reflecting subjectively perceived sleep difficulties. Nor was there any difference between violent and nonviolent condition for any single sleep item. Violent gaming induces different autonomic responses in boys compared to nonviolent gaming--during playing and during the following night--suggesting different emotional responses. Subjectively perceived sleep quality is not influenced after a single gaming experience. Future studies should address the development of the autonomic balance after gaming over longer

Thermal effect on heart rate and hemodynamics in vitelline arteries of stage 18 chicken embryos.

Science.gov (United States)

Lee, Jung Yeop; Lee, Sang Joon

2010-12-01

We investigated the thermal effects on heart rate, hemodynamics, and response of vitelline arteries of stage-18 chicken embryos. Heart rate was monitored by a high-speed imaging method, while hemodynamic quantities were evaluated using a particle image velocimetry (PIV) technique. Experiments were carried out at seven different temperatures (36-42 °C with 1 °C interval) after 1h of incubation to stabilize the heart rate. The heart rate increased in a linear manner (r = 0.992). Due to the increased cardiac output (or heart rate), the hemodynamic quantities such as mean velocity (U(mean)), velocity fluctuation (U(fluc)), and peak velocity (U(peak)) also increased with respect to the Womersley number (Ω) in the manner r = 0.599, 0.693, and 0.725, respectively. This indicates that the mechanical force exerting on the vessel walls increases. However, the active response (or regulation) of the vitelline arteries was not observed in this study. Copyright © 2010 Elsevier Ltd. All rights reserved.

Chronic intermittent hypoxia-hypercapnia blunts heart rate responses and alters neurotransmission to cardiac vagal neurons.

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Dyavanapalli, Jhansi; Jameson, Heather; Dergacheva, Olga; Jain, Vivek; Alhusayyen, Mona; Mendelowitz, David

2014-07-01

Patients with obstructive sleep apnoea experience chronic intermittent hypoxia-hypercapnia (CIHH) during sleep that elicit sympathetic overactivity and diminished parasympathetic activity to the heart, leading to hypertension and depressed baroreflex sensitivity. The parasympathetic control of heart rate arises from pre-motor cardiac vagal neurons (CVNs) located in nucleus ambiguus (NA) and dorsal motor nucleus of the vagus (DMNX). The mechanisms underlying diminished vagal control of heart rate were investigated by studying the changes in blood pressure, heart rate, and neurotransmission to CVNs evoked by acute hypoxia-hypercapnia (H-H) and CIHH. In vivo telemetry recordings of blood pressure and heart rate were obtained in adult rats during 4 weeks of CIHH exposure. Retrogradely labelled CVNs were identified in an in vitro brainstem slice preparation obtained from adult rats exposed either to air or CIHH for 4 weeks. Postsynaptic inhibitory or excitatory currents were recorded using whole cell voltage clamp techniques. Rats exposed to CIHH had increases in blood pressure, leading to hypertension, and blunted heart rate responses to acute H-H. CIHH induced an increase in GABAergic and glycinergic neurotransmission to CVNs in NA and DMNX, respectively; and a reduction in glutamatergic neurotransmission to CVNs in both nuclei. CIHH blunted the bradycardia evoked by acute H-H and abolished the acute H-H evoked inhibition of GABAergic transmission while enhancing glycinergic neurotransmission to CVNs in NA. These changes with CIHH inhibit CVNs and vagal outflow to the heart, both in acute and chronic exposures to H-H, resulting in diminished levels of cardioprotective parasympathetic activity to the heart as seen in OSA patients. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

Evaluation of therapy for dilated cardiomyopathy with heart failure by iodine-123 metaiodobenzyl-guanidine imaging. Comparison with heart rate variability power spectral analysis

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Li, Shou-lin; Ikeda, Jun; Takita, Tamotsu; Sekiguchi, Yohei; Demachi, Jun; Chikama, Hisao; Goto, Atsushi; Shirato, Kunio [Tohoku Univ., Sendai (Japan). School of Medicine

1998-11-01

The relationship between the myocardial uptake of iodine-123 metaiodobenzylguanidine ({sup 123}I-MIBG) and heart rate variability parameters has not been determined. This study determined the relationship between the change in myocardial uptake of {sup 123}I-MIBG and improvement in left ventricular function after treatment, to determine the usefulness of {sup 123}I-MIBG imaging to assess the effect of therapy on heart failure due to dilated cardiomyopathy (DCM). {sup 123}I-MIBG imaging and power spectral analysis of heart rate variability were performed before and after treatment in 17 patients with heart failure due to DCM. The following parameters were compared before and after treatment: New York Heart Association (NYHA) functional class, radiographic cardiothoracic ratio (CTR), blood pressure, echocardiographic data (left ventricular end-systolic (LVDs) and end-diastolic (LVDd) diameters, left ventricular ejection fraction (LVEF)), plasma concentrations of norepinephrine and epinephrine, heart rate variability power spectral analysis data (mean low frequency (MLF) and high frequency power (MHF)) and the myocardium to mediastinum activity ratio (MYO/M) obtained in early and late images, and washout rate calculated by anterior planar imaging of {sup 123}I-MIBG. The NYHA functional class, LVEF, LVDs, CTR, MLF and MHF improved after treatment. Early MYO/M and late MYO/M improved after treatment. The rate of increase in late MYO/M was positively correlated with the rate of improvement of LVEF after treatment. Furthermore, the late MYO/M was negatively correlated with MLF. Washout rate revealed no correlation with hemodynamic parameters. These findings suggest that late MYO/M is more useful than washout rate to assess the effect of treatment on heart failure due to DCM. Furthermore, the {sup 123}I-MIBG imaging and heart rate variability parameters are useful to assess the autonomic tone in DCM with heart failure. (author)

Evaluation of therapy for dilated cardiomyopathy with heart failure by iodine-123 metaiodobenzyl-guanidine imaging. Comparison with heart rate variability power spectral analysis

International Nuclear Information System (INIS)

Li, Shou-lin; Ikeda, Jun; Takita, Tamotsu; Sekiguchi, Yohei; Demachi, Jun; Chikama, Hisao; Goto, Atsushi; Shirato, Kunio

1998-01-01

The relationship between the myocardial uptake of iodine-123 metaiodobenzylguanidine ( 123 I-MIBG) and heart rate variability parameters has not been determined. This study determined the relationship between the change in myocardial uptake of 123 I-MIBG and improvement in left ventricular function after treatment, to determine the usefulness of 123 I-MIBG imaging to assess the effect of therapy on heart failure due to dilated cardiomyopathy (DCM). 123 I-MIBG imaging and power spectral analysis of heart rate variability were performed before and after treatment in 17 patients with heart failure due to DCM. The following parameters were compared before and after treatment: New York Heart Association (NYHA) functional class, radiographic cardiothoracic ratio (CTR), blood pressure, echocardiographic data (left ventricular end-systolic (LVDs) and end-diastolic (LVDd) diameters, left ventricular ejection fraction (LVEF)), plasma concentrations of norepinephrine and epinephrine, heart rate variability power spectral analysis data (mean low frequency (MLF) and high frequency power (MHF)) and the myocardium to mediastinum activity ratio (MYO/M) obtained in early and late images, and washout rate calculated by anterior planar imaging of 123 I-MIBG. The NYHA functional class, LVEF, LVDs, CTR, MLF and MHF improved after treatment. Early MYO/M and late MYO/M improved after treatment. The rate of increase in late MYO/M was positively correlated with the rate of improvement of LVEF after treatment. Furthermore, the late MYO/M was negatively correlated with MLF. Washout rate revealed no correlation with hemodynamic parameters. These findings suggest that late MYO/M is more useful than washout rate to assess the effect of treatment on heart failure due to DCM. Furthermore, the 123 I-MIBG imaging and heart rate variability parameters are useful to assess the autonomic tone in DCM with heart failure. (author)

Heart Rate Fragmentation: A Symbolic Dynamical Approach

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Madalena D. Costa

2017-11-01

Full Text Available Background: We recently introduced the concept of heart rate fragmentation along with a set of metrics for its quantification. The term was coined to refer to an increase in the percentage of changes in heart rate acceleration sign, a dynamical marker of a type of anomalous variability. The effort was motivated by the observation that fragmentation, which is consistent with the breakdown of the neuroautonomic-electrophysiologic control system of the sino-atrial node, could confound traditional short-term analysis of heart rate variability.Objective: The objectives of this study were to: (1 introduce a symbolic dynamical approach to the problem of quantifying heart rate fragmentation; (2 evaluate how the distribution of the different dynamical patterns (“words” varied with the participants' age in a group of healthy subjects and patients with coronary artery disease (CAD; and (3 quantify the differences in the fragmentation patterns between the two sample populations.Methods: The symbolic dynamical method employed here was based on a ternary map of the increment NN interval time series and on the analysis of the relative frequency of symbolic sequences (words with a pre-defined set of features. We analyzed annotated, open-access Holter databases of healthy subjects and patients with CAD, provided by the University of Rochester Telemetric and Holter ECG Warehouse (THEW.Results: The degree of fragmentation was significantly higher in older individuals than in their younger counterparts. However, the fragmentation patterns were different in the two sample populations. In healthy subjects, older age was significantly associated with a higher percentage of transitions from acceleration/deceleration to zero acceleration and vice versa (termed “soft” inflection points. In patients with CAD, older age was also significantly associated with higher percentages of frank reversals in heart rate acceleration (transitions from acceleration to

Increased heart rate variability during nondirective meditation.

Science.gov (United States)

Nesvold, Anders; Fagerland, Morten W; Davanger, Svend; Ellingsen, Øyvind; Solberg, Erik E; Holen, Are; Sevre, Knut; Atar, Dan

2012-08-01

Meditation practices are in use for relaxation and stress reduction. Some studies indicate beneficial cardiovascular health effects of meditation. The effects on the autonomous nervous system seem to vary among techniques. The purpose of the present study was to identify autonomic nerve activity changes during nondirective meditation. Heart rate variability (HRV), blood pressure variability (BPV), and baroreflex sensitivity (BRS) were monitored in 27 middle-aged healthy participants of both genders, first during 20 min regular rest with eyes closed, thereafter practising Acem meditation for 20 min. Haemodynamic and autonomic data were collected continuously (beat-to-beat) and non-invasively. HRV and BPV parameters were estimated by power spectral analyses, computed by an autoregressive model. Spontaneous activity of baroreceptors were determined by the sequence method. Primary outcomes were changes in HRV, BPV, and BRS between rest and meditation. HRV increased in the low-frequency (LF) and high-frequency (HF) bands during meditation, compared with rest (p = 0.014, 0.013, respectively). Power spectral density of the RR-intervals increased as well (p = 0.012). LF/HF ratio decreased non-significantly, and a reduction of LF-BPV power was observed during meditation (p < 0.001). There was no significant difference in BRS. Respiration and heart rates remained unchanged. Blood pressure increased slightly during meditation. There is an increased parasympathetic and reduced sympathetic nerve activity and increased overall HRV, while practising the technique. Hence, nondirective meditation by the middle aged may contribute towards a reduction of cardiovascular risk.

The SNAPSHOT study protocol: SNAcking, Physical activity, Self-regulation, and Heart rate Over Time.

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McMinn, David; Allan, Julia L

2014-09-26

The cognitive processes responsible for effortful behavioural regulation are known as the executive functions, and are implicated in several factors associated with behaviour control, including focussing on tasks, resisting temptations, planning future actions, and inhibiting prepotent responses. Similar to muscles, the executive functions become fatigued following intensive use (e.g. stressful situations, when tired or busy, and when regulating behaviour such as quitting smoking). Therefore, an individual may be more susceptible to engaging in unhealthy behaviours when their executive functions are depleted. In the present study we investigate associations between the executive functions, snack food consumption, and sedentary behaviour in real time. We hypothesise that individuals may be more susceptible to unhealthy snacking and sedentary behaviours during periods when their executive functions are depleted. We test this hypothesis using real-time objective within-person measurements. A sample of approximately 50 Scottish adults from varied socio-economic, working, and cultural backgrounds will participate in the three phases of the SNAcking, Physical activity, Self-regulation, and Heart rate Over Time (SNAPSHOT) study. Phase one will require participants to complete home-based questionnaires concerned with diet, eating behaviour, and physical activity (≈1.5 hours to complete). Phase two will constitute a 2-3 hour psychological laboratory testing session during which trait-level executive function, general intelligence, and diet and physical activity intentions, past behaviour, and automaticity will be measured. The final phase will involve a 7-day ambulatory protocol during which objective repeated assessments of executive function, snacking behaviour, physical activity, mood, heart rate, perceived energy level, current context and location will be measured during participants' daily routines. Multi-level regression analysis, accounting for observations nested

Heart Rate Changes in Electroacupuncture Treated Polycystic Ovary in Rats.

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Ramadoss, Mukilan; Ramanathan, Gunasekaran; Subbiah, Angelie Jessica; Natrajan, Chidambaranathan

2016-03-01

Polycystic Ovary Syndrome (PCOS) is a common metabolic disorder, it affects both humans and animals. It may induce coronary heart disease, obesity and hyperandrogenism. Previous studies show that Low frequency Electroacupuncture (EA) have an effect on PCOS, however the exact pathway is unclear. To find the effect of EA on autonomic activity of the heart in Estradiol Valerate (EV) induced PCOS rats. Heart rate variability (HRV) was assessed in 3 groups: 1) Control; 2) PCOS rats; and 3) PCOS rats after EA treatment (n=8 in each group). From the time domain analysis and frequency domain analysis (linear measures) HRV analysis was done. EA stimulation was given at low frequency of 2Hz for 15 min on alternate days for 4-5 weeks. Collected data were statistically analysed using One-Way Analysis of Variance with the application of multiple comparisons of Tukey test. EA treatment group shows significant reduction in Heart Rate (HR) and low frequency, high frequency ratio (LF/HF); and increase in RR interval, Total Power (TP) when compared to PCOS group. The study concludes that EA treatment has a significant effect on reducing sympathetic tone and decreasing HR in PCOS.

Monitoring nocturnal heart rate with bed sensor.

Science.gov (United States)

Migliorini, M; Kortelainen, J M; Pärkkä, J; Tenhunen, M; Himanen, S L; Bianchi, A M

2014-01-01

This article is part of the Focus Theme of Methods of Information in Medicine on "Biosignal Interpretation: Advanced Methods for Studying Cardiovascular and Respiratory Systems". The aim of this study is to assess the reliability of the estimated Nocturnal Heart Rate (HR), recorded through a bed sensor, compared with the one obtained from standard electrocardiography (ECG). Twenty-eight sleep deprived patients were recorded for one night each through matrix of piezoelectric sensors, integrated into the mattress, through polysomnography (PSG) simultaneously. The two recording methods have been compared in terms of signal quality and differences in heart beat detection. On average, coverage of 92.7% of the total sleep time was obtained for the bed sensor, testifying the good quality of the recordings. The average beat-to-beat error of the inter-beat intervals was 1.06%. These results suggest a good overall signal quality, however, considering fast heart rates (HR > 100 bpm), performances were worse: in fact, the sensitivity in the heart beat detection was 28.4% while the false positive rate was 3.8% which means that a large amount of fast beats were not detected. The accuracy of the measurements made using the bed sensor has less than 10% of failure rate especially in periods with HR lower than 70 bpm. For fast heart beats the uncertainty increases. This can be explained by the change in morphology of the bed sensor signal in correspondence of a higher HR.

An EEMD-PCA approach to extract heart rate, respiratory rate and respiratory activity from PPG signal.

Science.gov (United States)

Motin, Mohammod Abdul; Karmakar, Chandan Kumar; Palaniswami, Marimuthu

2016-08-01

The pulse oximeter's photoplethysmographic (PPG) signals, measure the local variations of blood volume in tissues, reflecting the peripheral pulse modulated by cardiac activity, respiration and other physiological effects. Therefore, PPG can be used to extract the vital cardiorespiratory signals like heart rate (HR), respiratory rate (RR) and respiratory activity (RA) and this will reduce the number of sensors connected to the patient's body for recording vital signs. In this paper, we propose an algorithm based on ensemble empirical mode decomposition with principal component analysis (EEMD-PCA) as a novel approach to estimate HR, RR and RA simultaneously from PPG signal. To examine the performance of the proposed algorithm, we used 45 epochs of PPG, electrocardiogram (ECG) and respiratory signal extracted from the MIMIC database (Physionet ATM data bank). The ECG and capnograph based respiratory signal were used as the ground truth and several metrics such as magnitude squared coherence (MSC), correlation coefficients (CC) and root mean square (RMS) error were used to compare the performance of EEMD-PCA algorithm with most of the existing methods in the literature. Results of EEMD-PCA based extraction of HR, RR and RA from PPG signal showed that the median RMS error (quartiles) obtained for RR was 0 (0, 0.89) breaths/min, for HR was 0.62 (0.56, 0.66) beats/min and for RA the average value of MSC and CC was 0.95 and 0.89 respectively. These results illustrated that the proposed EEMD-PCA approach is more accurate in estimating HR, RR and RA than other existing methods.

Hydroxychloroquine reduces heart rate by modulating the hyperpolarization-activated current If: Novel electrophysiological insights and therapeutic potential

Science.gov (United States)

Capel, Rebecca A.; Herring, Neil; Kalla, Manish; Yavari, Arash; Mirams, Gary R.; Douglas, Gillian; Bub, Gil; Channon, Keith; Paterson, David J.; Terrar, Derek A.; Burton, Rebecca-Ann B.

2015-01-01

Background Bradycardic agents are of interest for the treatment of ischemic heart disease and heart failure, as heart rate is an important determinant of myocardial oxygen consumption. Objectives The purpose of this study was to investigate the propensity of hydroxychloroquine (HCQ) to cause bradycardia. Methods We assessed the effects of HCQ on (1) cardiac beating rate in vitro (mice); (2) the “funny” current (If) in isolated guinea pig sinoatrial node (SAN) myocytes (1, 3, 10 µM); (3) heart rate and blood pressure in vivo by acute bolus injection (rat, dose range 1–30 mg/kg), (4) blood pressure and ventricular function during feeding (mouse, 100 mg/kg/d for 2 wk, tail cuff plethysmography, anesthetized echocardiography). Results In mouse atria, spontaneous beating rate was significantly (P < .05) reduced (by 9% ± 3% and 15% ± 2% at 3 and 10 µM HCQ, n = 7). In guinea pig isolated SAN cells, HCQ conferred a significant reduction in spontaneous action potential firing rate (17% ± 6%, 1 μM dose) and a dose-dependent reduction in If (13% ± 3% at 1 µM; 19% ± 2% at 3 µM). Effects were also observed on L-type calcium ion current (ICaL) (12% ± 4% reduction) and rapid delayed rectifier potassium current (IKr) (35% ± 4%) at 3 µM. Intravenous HCQ decreased heart rate in anesthetized rats (14.3% ± 1.1% at 15mg/kg; n = 6) without significantly reducing mean arterial blood pressure. In vivo feeding studies in mice showed no significant change in systolic blood pressure nor left ventricular function. Conclusions We have shown that HCQ acts as a bradycardic agent in SAN cells, in atrial preparations, and in vivo. HCQ slows the rate of spontaneous action potential firing in the SAN through multichannel inhibition, including that of If. PMID:26025323

Quantification of pulmonary thallium-201 activity after upright exercise in normal persons: importance of peak heart rate and propranolol usage in defining normal values

International Nuclear Information System (INIS)

Brown, K.A.; Boucher, C.A.; Okada, R.D.; Strauss, H.W.; Pohost, G.M.

1984-01-01

Fifty-nine normal patients (34 angiographically normal and 25 clinically normal by Bayesian analysis) underwent thallium-201 imaging after maximal upright exercise. Lung activity was quantitated relative to myocardial activity and a lung/myocardial activity ratio was determined for each patient. Stepwise regression analysis was then used to examine the influence of patient clinical characteristics and exercise variables on the lung/myocardium ratio. Peak heart rate during exercise and propranolol usage both showed significant negative regression coefficients (p less than 0.001). No other patient data showed a significant relation. Using the regression equation and the estimated variance, a 95% confidence level upper limit of normal could be determined for a give peak heart rate and propranolol status. Sixty-one other patients were studied to validate the predicted upper limits of normal based on this model. None of the 27 patients without coronary artery disease had an elevated lung/myocardial ratio, compared with 1 of 8 with 1-vessel disease (difference not significant), 6 of 14 with 2-vessel disease (p less than 0.005), and 6 of 12 with 3-vessel disease (p less than 0.0001). Thus, lung activity on upright exercise thallium-201 studies can be quantitated relative to myocardial activity, and is inversely related to peak heart rate and propranolol use. Use of a regression analysis allows determination of a 95% confidence upper limit of normal to be anticipated in an individual patient

Heart rate, salivary α-amylase activity, and cooperative behavior in previously naïve children receiving dental local anesthesia.

Science.gov (United States)

Arhakis, Aristidis; Menexes, George; Coolidge, Trilby; Kalfas, Sotirios

2012-01-01

Psychosomatic indicators, such as heart rate (HR), salivary alpha amylase (sAA) activity, and behavior, can be used to determine stress. This study's aim was to assess the pattern of changes of salivary alpha amylase, heart rate, and cooperative behavior in previously naïve children receiving dental treatment under local anesthesia. Included were 30 children with no prior dental experience who needed 4 or more sessions of dental treatment involving local anesthesia. In each session, sAA, HR, and behavior were assessed before and during the application of local anesthesia and at the end of the treatment. The highest sAA value was always observed at the end of each session; overall, the value was lower in the fourth session. HR always increased during the local anesthesia, and did not vary across sessions. No significant relationship was found between child cooperation and either sAA or HR. In this sample, child cooperation may not be an accurate indicator of stress. Based on salivary alpha amylase activity changes, dental treatment involving local anesthesia in naïve children appeared to be less stressful after 3 sessions.

Peculiarities of vegetative regulation of heart rate in wrestlers of different age groups

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E.B. Zapovitriana

2015-04-01

Full Text Available Purpose : the aim of the work was to study the characteristics of vegetative regulation of cardiac rhythm in athletes of high qualification of different age groups. Material : 26 wrestlers of Greco-Roman style of high qualification aged 19-34 years old were studied. Vegetative regulation was assessed by statistical analysis of heart rate variability using cardiac monitors «Polar RS800CX». Results : the results showed that the wrestlers of older age group has a greater level of tension of regulation of heart rhythm for compared with young athletes. This is confirmed by the reduced values of the mean square deviation RR- intervals and triangular index. According to the results of spectral analysis of cardio revealed activation of parasympathetic tone of the autonomic regulation of the heart rhythm of wrestlers in older age group, compared with young athletes. The increase of tension of regulation of heart rate in the wrestlers of older age group accompanied by a slowdown of aperiodic and periodic oscillations of cardio intervals. Conclusions: the high level of tension of regulation of heart rhythm in older wrestlers group (26-34 accompanied by the activation of neurohumoral centers and parasympathetic link of vegetative nervous system.

SVM-Based Spectral Analysis for Heart Rate from Multi-Channel WPPG Sensor Signals.

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Xiong, Jiping; Cai, Lisang; Wang, Fei; He, Xiaowei

2017-03-03

Although wrist-type photoplethysmographic (hereafter referred to as WPPG) sensor signals can measure heart rate quite conveniently, the subjects' hand movements can cause strong motion artifacts, and then the motion artifacts will heavily contaminate WPPG signals. Hence, it is challenging for us to accurately estimate heart rate from WPPG signals during intense physical activities. The WWPG method has attracted more attention thanks to the popularity of wrist-worn wearable devices. In this paper, a mixed approach called Mix-SVM is proposed, it can use multi-channel WPPG sensor signals and simultaneous acceleration signals to measurement heart rate. Firstly, we combine the principle component analysis and adaptive filter to remove a part of the motion artifacts. Due to the strong relativity between motion artifacts and acceleration signals, the further denoising problem is regarded as a sparse signals reconstruction problem. Then, we use a spectrum subtraction method to eliminate motion artifacts effectively. Finally, the spectral peak corresponding to heart rate is sought by an SVM-based spectral analysis method. Through the public PPG database in the 2015 IEEE Signal Processing Cup, we acquire the experimental results, i.e., the average absolute error was 1.01 beat per minute, and the Pearson correlation was 0.9972. These results also confirm that the proposed Mix-SVM approach has potential for multi-channel WPPG-based heart rate estimation in the presence of intense physical exercise.

Effects of slow breathing rate on heart rate variability and arterial baroreflex sensitivity in essential hypertension.

Science.gov (United States)

Li, Changjun; Chang, Qinghua; Zhang, Jia; Chai, Wenshu

2018-05-01

This study is to investigate the effects of slow breathing on heart rate variability (HRV) and arterial baroreflex sensitivity in essential hypertension.We studied 60 patients with essential hypertension and 60 healthy controls. All subjects underwent controlled breathing at 8 and 16 breaths per minute. Electrocardiogram, respiratory, and blood pressure signals were recorded simultaneously. We studied effects of slow breathing on heart rate, blood pressure and respiratory peak, high-frequency (HF) power, low-frequency (LF) power, and LF/HF ratio of HRV with traditional and corrected spectral analysis. Besides, we tested whether slow breathing was capable of modifying baroreflex sensitivity in hypertensive subjects.Slow breathing, compared with 16 breaths per minute, decreased the heart rate and blood pressure (all P hypertensive subjects. Slow breathing increased baroreflex sensitivity in hypertensive subjects (from 59.48 ± 6.39 to 78.93 ± 5.04 ms/mm Hg, P hypertension. Besides, slow breathing increased baroreflex sensitivity in hypertensive subjects. These demonstrate slow breathing is indeed capable of shifting sympatho-vagal balance toward vagal activities and increasing baroreflex sensitivity, suggesting a safe, therapeutic approach for essential hypertension.

Sympathetic Activity, Assessed by Power Spectral Analysis of Heart Rate Variability, in White-Coat, Masked and Sustained Hypertension Versus True Normotension

Czech Academy of Sciences Publication Activity Database

Fagard, R.H.; Stolarz, K.; Kuznetsova, T.; Seidlerová, J.; Tikhonoff, V.; Grodzicki, T.; Nikitin, Y.; Filipovský, J.; Peleška, Jan; Casiglia, E.; Thijs, L.; Staessen, J.A.; Kawecka-Jaszcz, K.

2007-01-01

Roč. 25, č. 11 (2007), s. 2280-2285 ISSN 0263-6352 Institutional research plan: CEZ:AV0Z10300504 Keywords : heart rate variability * masked hypertension * power spectral analysis * sympathetic activity * white-coat hypertension Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.364, year: 2007

Using heart rate to predict energy expenditure in large domestic dogs.

Science.gov (United States)

Gerth, N; Ruoß, C; Dobenecker, B; Reese, S; Starck, J M

2016-06-01

The aim of this study was to establish heart rate as a measure of energy expenditure in large active kennel dogs (28 ± 3 kg bw). Therefore, the heart rate (HR)-oxygen consumption (V˙O2) relationship was analysed in Foxhound-Boxer-Ingelheim-Labrador cross-breds (FBI dogs) at rest and graded levels of exercise on a treadmill up to 60-65% of maximal aerobic capacity. To test for effects of training, HR and V˙O2 were measured in female dogs, before and after a training period, and after an adjacent training pause to test for reversibility of potential effects. Least squares regression was applied to describe the relationship between HR and V˙O2. The applied training had no statistically significant effect on the HR-V˙O2 regression. A general regression line from all data collected was prepared to establish a general predictive equation for energy expenditure from HR in FBI dogs. The regression equation established in this study enables fast estimation of energy requirement for running activity. The equation is valid for large dogs weighing around 30 kg that run at ground level up to 15 km/h with a heart rate maximum of 190 bpm irrespective of the training level. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Effect of oxygen treatment on heart rate after abdominal surgery

DEFF Research Database (Denmark)

Rosenberg-Adamsen, S; Lie, C; Bernhard, A

1999-01-01

BACKGROUND: Cardiac complications are common during the postoperative period and may be associated with hypoxemia and tachycardia. Preliminary studies in high-risk patients after operation have shown a possible beneficial effect of oxygen therapy on arterial oxygen saturation and heart rate....... METHODS: The authors studied the effect of oxygen therapy on arterial oxygen saturation and heart rate in 100 consecutive unselected patients randomly and double blindly allocated to receive air or oxygen therapy between the first and fourth day after major abdominal surgery. RESULTS: The median arterial...... oxygen saturation rate increased significantly from 96% to 99% (P heart rate decreased significantly from 85 beats/min to 81 beats/min (P heart rate occurred...

Heart rate and time-motion analyses in top junior players during basketball matches

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Karel Hůlka

2013-09-01

Full Text Available BACKGROUND: Basketball performance can be classified as an intermittent physical activity due to the changing situational game conditions and the number of intervening variables. It is necessary to have detailed knowledge about the performance of basketball players during a match as a background for more specific planning of the training process. OBJECTIVE: The aim of this study was to analyse the indicators of internal and external load of basketball player’s performance during a match of U18 top men basketball players as a background for the planning of specific training processes. METHODS: Thirty-two Czech top junior basketball players (male, aged 16.88 ± 0.72 years participated in this research. The heart rate was recorded and time-motion analysis was conducted during six warm-up matches. RESULTS: The average heart rate was measured to be 167.47 ± 13.01 beats • min.–1, which corresponded to 85.06 ± 6.40% of peak heart rate. The percentages of the total time spent over and under 85% were 63.12% and 36.88%, respectively. Average distance covered was measured to be 5,880.91 ± 831.01 meters. The average work : rest ratio was 1 : 7.95 ± 1.83, ranging from 1 : 4.80 to 1 : 10.92. CONCLUSIONS: The results from these matches suggest that the exercise intensity and sprint activity observed during junior basketball are dependent on the player's position and partly on the level of the performance. The heart rate during a match was not dependent on the positions, however, time-motion analysis revealed significant differences between three basketball positions during a match. The combination of heart rate and time-motion analysis is recommended.

Evidence that BDNF regulates heart rate by a mechanism involving increased brainstem parasympathetic neuron excitability

OpenAIRE

Wan, Ruiqian; Weigand, Letitia A.; Bateman, Ryan; Griffioen, Kathleen; Mendelowitz, David; Mattson, Mark P.

2014-01-01

Autonomic control of heart rate is mediated by cardioinhibitory parasympathetic cholinergic neurons located in the brainstem and stimulatory sympathetic noradrenergic neurons. During embryonic development the survival and cholinergic phenotype of brainstem autonomic neurons is promoted by brain-derived neurotrophic factor (BDNF). We now provide evidence that BDNF regulates heart rate by a mechanism involving increased brainstem cardioinhibitory parasympathetic activity. Mice with a BDNF haplo...

Blood Pressure vs. Heart Rate

Science.gov (United States)

... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Blood Pressure vs. Heart Rate (Pulse) Updated:Nov 13,2017 ... This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP Introduction What ...

Heart Rate, Stress, and Occupational Noise Exposure among Electronic Waste Recycling Workers

Directory of Open Access Journals (Sweden)

Katrina N. Burns

2016-01-01

Full Text Available Electronic waste (e-waste is a growing occupational and environmental health issue around the globe. E-waste recycling is a green industry of emerging importance, especially in low-and middle-income countries where much of this recycling work is performed, and where many people’s livelihoods depend on this work. The occupational health hazards of e-waste recycling have not been adequately explored. We performed a cross-sectional study of noise exposures, heart rate, and perceived stress among e-waste recycling workers at a large e-waste site in Accra, Ghana. We interviewed 57 workers and continuously monitored their individual noise exposures and heart rates for up to 24 h. More than 40% of workers had noise exposures that exceeded recommended occupational (85 dBA and community (70 dBA noise exposure limits, and self-reported hearing difficulties were common. Workers also had moderate to high levels of perceived stress as measured via Cohen’s Perceived Stress Scale, and reported a variety of symptoms that could indicate cardiovascular disease. Noise exposures were moderately and significantly correlated with heart rate (Spearman’s ρ 0.46, p < 0.001. A mixed effects linear regression model indicated that a 1 dB increase in noise exposure was associated with a 0.17 increase in heart rate (p-value = 0.01 even after controlling for work activities, age, smoking, perceived stress, and unfavorable physical working conditions. These findings suggest that occupational and non-occupational noise exposure is associated with elevations in average heart rate, which may in turn predict potential cardiovascular damage.

[Heart rate variability and physical exercise. Current status].

Science.gov (United States)

Hottenrott, Kuno; Hoos, Olaf; Esperer, Hans Dieter

2006-09-01

Heart rate variability (HRV) has long been used in risk stratification for sudden cardiac death and diabetic autonomic neuropathy. In recent years, both time and frequency domain indices of HRV also gained increasing interest in sports and training sciences. In these fields, HRV is currently used for the noninvasive assessment of autonomic changes associated with short-term and long-term endurance exercise training in both leisure sports activity and high-performance training. Furthermore, HRV is being investigated as a diagnostic marker of overreaching and overtraining.A large body of evidence shows that, in healthy subjects and cardiovascular patients of all ages (up to an age of 70 years), regular aerobic training usually results in a significant improvement of overall as well as instantaneous HRV. These changes, which are accompanied by significant reductions in heart rates both at rest and during submaximal exercise, reflect an increase in autonomic efferent activity and a shift in favor of enhanced vagal modulation of the cardiac rhythm. Regular aerobic training of moderate volume and intensity over a minimum period of 3 months seems to be necessary to ensure these effects, which might be associated with a prognostic benefit regarding overall mortality.At present, available data does not allow for final conclusions with respect to the usefulness of traditional HRV indices in assessing an individual's exercise performance and monitoring training load. The discrepant results published so far are due to several factors including insufficient study size and design, and different HRV methods. Large-sized and prospectively designed studies are necessary for clarification. It also remains to be seen, whether the traditional HRV indices prove useful in the diagnosis of overreaching and overtraining. Preliminary results, though promising, need to be confirmed in larger cohorts.A basic problem in HRV analysis is nonstationarity of the heart rate signal, which holds

Heart rate variability: a tool to explore the sleeping brain?

OpenAIRE

Chouchou, Florian; Desseilles, Martin

2014-01-01

Sleep is divided into two main sleep stages: (1) non-rapid eye movement sleep (non-REMS), characterized among others by reduced global brain activity; and (2) rapid eye movement sleep (REMS), characterized by global brain activity similar to that of wakefulness. Results of heart rate variability (HRV) analysis, which is widely used to explore autonomic modulation, have revealed higher parasympathetic tone during normal non-REMS and a shift toward sympathetic predominance during normal REMS. M...

Paradoxical dissociation between heart rate and heart rate variability following different modalities of exercise in individuals with metabolic syndrome: The RESOLVE study.

Science.gov (United States)

Boudet, Gil; Walther, Guillaume; Courteix, Daniel; Obert, Philippe; Lesourd, Bruno; Pereira, Bruno; Chapier, Robert; Vinet, Agnès; Chamoux, Alain; Naughton, Geraldine; Poirier, Paul; Dutheil, Frédéric

2017-02-01

Aims To analyse the effects of different modalities of exercise training on heart rate variability (HRV) in individuals with metabolic syndrome (MetS). Methods and results Eighty MetS participants (aged 50-70 years) were housed and managed in an inpatient medical centre for 21 days, including weekends. Physical activity and food intake/diet were intensively monitored. Participants were randomly assigned into three training groups, differing only by intensity of exercise: moderate-endurance-moderate-resistance ( re), high-resistance-moderate-endurance ( Re), and moderate-resistance-high-endurance ( rE). HRV was recorded before and after the intervention by 24-hour Holter electrocardiogram. Although mean 24-hour heart rate decreased more in Re than re (-11.6 ± 1.6 vs. -4.8 ± 2.1%; P = 0.010), low frequency/high frequency decreased more in re than Re (-20.4 ± 5.5% vs. + 20.4 ± 9.1%; P = 0.002) and rE (-20.4 ± 5.5% vs. -0.3 ± 11.1%; P = 0.003). Very low frequency increased more in Re than re (+121.2 ± 35.7 vs. 42.9 ± 11.3%; P = 0.004). For all HRV parameters, rE ranged between re and Re values. Low frequency/high frequency changes were linked with visceral fat loss only in re (coefficient 5.9, 95% CI 1.9-10.0; P = 0.004). By day 21, HRV parameters of MetS groups (heart rate -8.6 ± 1.0%, standard deviation of R-R intervals + 34.0 ± 6.6%, total power + 63.3 ± 11.1%; P < 0.001) became closer to values of 50 aged-matched healthy controls. Conclusions A 3-week residential programme with intensive volumes of physical activity (15-20 hours per week) enhanced HRV in individuals with MetS. Participants with moderate intensity of training had greater improvements in sympathovagal balance, whereas those with high intensity in resistance training had greater decreases in heart rate and greater increases in very low frequency. Modality-specific relationships were observed between enhanced HRV

Exaggerated heart rate oscillations during two meditation techniques.

Science.gov (United States)

Peng, C K; Mietus, J E; Liu, Y; Khalsa, G; Douglas, P S; Benson, H; Goldberger, A L

1999-07-31

We report extremely prominent heart rate oscillations associated with slow breathing during specific traditional forms of Chinese Chi and Kundalini Yoga meditation techniques in healthy young adults. We applied both spectral analysis and a novel analytic technique based on the Hilbert transform to quantify these heart rate dynamics. The amplitude of these oscillations during meditation was significantly greater than in the pre-meditation control state and also in three non-meditation control groups: i) elite athletes during sleep, ii) healthy young adults during metronomic breathing, and iii) healthy young adults during spontaneous nocturnal breathing. This finding, along with the marked variability of the beat-to-beat heart rate dynamics during such profound meditative states, challenges the notion of meditation as only an autonomically quiescent state.

Association of heart rate profile during exercise with the severity of coronary artery disease.

Science.gov (United States)

Cay, Serkan; Ozturk, Sezgin; Biyikoglu, Funda; Yildiz, Abdulkadir; Cimen, Tolga; Uygur, Belma; Tuna, Funda

2009-05-01

Coronary artery disease is the leading cause of morbidity and mortality around the world. Autonomic nervous system abnormalities are associated with coronary artery disease and its complications. Exercise stress tests are routinely used for the detection of the presence of coronary artery disease. In this study, we observed the association between heart rate profile during exercise and the severity of coronary artery disease. One hundred and sixty patients with abnormal exercise treadmill test (> or =1 mm horizontal or downsloping ST-segment depression; 119 men, 41 women; mean age = 57 +/- 9 years) were included in the study. Use of any drug affecting heart rate was not permitted. Resting heart rate before exercise, maximum heart rate during exercise, and resting heart rate after exercise (5 min later) were measured and two parameters were calculated: heart rate increment (maximum heart rate - resting heart rate before exercise) and heart rate decrement (maximum heart rate - resting heart rate after exercise). All patients underwent selective coronary angiography and subclassified into two groups according to stenotic lesion severity. Group 1 had at least 50% of stenotic lesion and group 2 had less than 50%. Patients in the first group had increased resting heart rate, decreased maximum heart rate, decreased heart rate increment, and decreased heart rate decrement compared with second group. All patients were classified into tertiles of resting heart rate, heart rate increment, and heart rate decrement level to evaluate whether these parameters were associated with severity of coronary artery stenosis in the study. The multiple-adjusted odds ratio of the risk of severe coronary atherosclerosis was 21.888 (95% confidence interval 6.983-68.606) for the highest tertile of resting heart rate level compared with the lowest tertile. In addition, the multiple-adjusted odds ratio of the risk of severe coronary atherosclerosis was 20.987 (95% confidence interval 6

Discovery of novel heart rate-associated loci using the Exome Chip

DEFF Research Database (Denmark)

van den Berg, Marten E; Warren, Helen R; Cabrera, Claudia P

2017-01-01

Resting heart rate is a heritable trait, and an increase in heart rate is associated with increased mortality risk. Genome-wide association study analyses have found loci associated with resting heart rate, at the time of our study these loci explained 0.9% of the variation. This study aims to di......) and fetal muscle samples by including our novel variants.Our findings advance the knowledge of the genetic architecture of heart rate, and indicate new candidate genes for follow-up functional studies....

A randomised, simulated study assessing auscultation of heart rate at birth

NARCIS (Netherlands)

Voogdt, Kevin G. J. A.; Morrison, Allison C.; Wood, Fiona E.; van Elburg, Ruurd M.; Wyllie, Jonathan P.

2010-01-01

Heart rate is a primary clinical indicator directing newborn resuscitation. The time taken to assess the heart rate by auscultation in relation to accuracy during newborn resuscitation is not known. To assess both the accuracy and time taken to assess heart rate by stethoscope in simulated

Heart Rate Variability: New Perspectives on Physiological Mechanisms, Assessment of Self-regulatory Capacity, and Health risk.

Science.gov (United States)

McCraty, Rollin; Shaffer, Fred

2015-01-01

Heart rate variability, the change in the time intervals between adjacent heartbeats, is an emergent property of interdependent regulatory systems that operates on different time scales to adapt to environmental and psychological challenges. This article briefly reviews neural regulation of the heart and offers some new perspectives on mechanisms underlying the very low frequency rhythm of heart rate variability. Interpretation of heart rate variability rhythms in the context of health risk and physiological and psychological self-regulatory capacity assessment is discussed. The cardiovascular regulatory centers in the spinal cord and medulla integrate inputs from higher brain centers with afferent cardiovascular system inputs to adjust heart rate and blood pressure via sympathetic and parasympathetic efferent pathways. We also discuss the intrinsic cardiac nervous system and the heart-brain connection pathways, through which afferent information can influence activity in the subcortical, frontocortical, and motor cortex areas. In addition, the use of real-time HRV feedback to increase self-regulatory capacity is reviewed. We conclude that the heart's rhythms are characterized by both complexity and stability over longer time scales that reflect both physiological and psychological functional status of these internal self-regulatory systems.

Effects of Malaria on Blood Pressure, Heart Rate, Electrocardiogram ...

African Journals Online (AJOL)

The effect of malaria on blood pressure, heart rate, electrocardiogram and the cardiovascular responses to postural change were studied in malaria patients. Blood pressure was measured by the sphygmomanometric-auscultatory method. Standard ECG machine was used to record the electrocardiogram. Heart rate was ...

Probability of detection of clinical seizures using heart rate changes.

Science.gov (United States)

Osorio, Ivan; Manly, B F J

2015-08-01

Heart rate-based seizure detection is a viable complement or alternative to ECoG/EEG. This study investigates the role of various biological factors on the probability of clinical seizure detection using heart rate. Regression models were applied to 266 clinical seizures recorded from 72 subjects to investigate if factors such as age, gender, years with epilepsy, etiology, seizure site origin, seizure class, and data collection centers, among others, shape the probability of EKG-based seizure detection. Clinical seizure detection probability based on heart rate changes, is significantly (pprobability of detecting clinical seizures (>0.8 in the majority of subjects) using heart rate is highest for complex partial seizures, increases with a patient's years with epilepsy, is lower for females than for males and is unrelated to the side of hemisphere origin. Clinical seizure detection probability using heart rate is multi-factorially dependent and sufficiently high (>0.8) in most cases to be clinically useful. Knowledge of the role that these factors play in shaping said probability will enhance its applicability and usefulness. Heart rate is a reliable and practical signal for extra-cerebral detection of clinical seizures originating from or spreading to central autonomic network structures. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

SVM-Based Spectral Analysis for Heart Rate from Multi-Channel WPPG Sensor Signals

Directory of Open Access Journals (Sweden)

Jiping Xiong

2017-03-01

Full Text Available Although wrist-type photoplethysmographic (hereafter referred to as WPPG sensor signals can measure heart rate quite conveniently, the subjects’ hand movements can cause strong motion artifacts, and then the motion artifacts will heavily contaminate WPPG signals. Hence, it is challenging for us to accurately estimate heart rate from WPPG signals during intense physical activities. The WWPG method has attracted more attention thanks to the popularity of wrist-worn wearable devices. In this paper, a mixed approach called Mix-SVM is proposed, it can use multi-channel WPPG sensor signals and simultaneous acceleration signals to measurement heart rate. Firstly, we combine the principle component analysis and adaptive filter to remove a part of the motion artifacts. Due to the strong relativity between motion artifacts and acceleration signals, the further denoising problem is regarded as a sparse signals reconstruction problem. Then, we use a spectrum subtraction method to eliminate motion artifacts effectively. Finally, the spectral peak corresponding to heart rate is sought by an SVM-based spectral analysis method. Through the public PPG database in the 2015 IEEE Signal Processing Cup, we acquire the experimental results, i.e., the average absolute error was 1.01 beat per minute, and the Pearson correlation was 0.9972. These results also confirm that the proposed Mix-SVM approach has potential for multi-channel WPPG-based heart rate estimation in the presence of intense physical exercise.

"Heart rate-dependent" electrocardiographic diagnosis of left ventricular hypertrophy.

Science.gov (United States)

Madias, John E

2013-05-01

A case is presented revealing the common phenomenon of heart rate-dependent diagnosis of electrocardiographic (ECG) diagnosis of left ventricular hypertrophy (LVH), which consists of satisfaction of LVH criteria only at faster rates whereas ECGs with a slow heart rate do not satisfy such criteria. The mechanism of the phenomenon has been attributed to the tachycardia-mediated underfilling of the left ventricle bringing the electrical "centroid" of the heart closer to the recording electrodes, which results in augmentation of the amplitude of QRS complexes, particularly in leads V2-V4. ©2012, The Author. Journal compilation ©2012 Wiley Periodicals, Inc.

The antiarrhythmic effect of vagal stimulation after acute coronary occlusion: Role of the heart rate.

Science.gov (United States)

Manati, Waheed; Pineau, Julien; Doñate Puertas, Rosa; Morel, Elodie; Quadiri, Timour; Bui-Xuan, Bernard; Chevalier, Philippe

2018-01-03

Strong evidence suggests a causal link between autonomic disturbances and ventricular arrhythmias. However, the mechanisms underlying the antiarrhythmic effect of vagal stimulation are poorly understood. The vagal antiarrhythmic effect might be modulated by a decrease in heart rate. the proximal anterior interventricular artery was occluded in 16 pigs by clamping under general anaesthesia. Group 1: heart rates remained spontaneous (n = 6; 12 occlusions); Group 2: heart rates were fixed at 190 beats per minute (bpm) with atrial electrical stimulation (n = 10; 20 occlusions). Each pig received two occlusions, 30 min apart, one without and one with vagal stimulation (10 Hz, 2 ms, 5-20 mA). The antiarrhythmic effect of vagal activation was defined as the time to the appearance of ventricular fibrillation (VF) after occlusion. In Group 1, vagal stimulation triggered a significant decrease in basal heart rate (132 ± 4 vs. 110 ± 17 bpm, p coronary occlusion (1102 ± 85 vs. 925 ± 41 s, p acute coronary occlusion.

HEART RATE VARIABILITY CLASSIFICATION USING SADE-ELM CLASSIFIER WITH BAT FEATURE SELECTION

Directory of Open Access Journals (Sweden)

R Kavitha

2017-07-01

Full Text Available The electrical activity of the human heart is measured by the vital bio medical signal called ECG. This electrocardiogram is employed as a crucial source to gather the diagnostic information of a patient’s cardiopathy. The monitoring function of cardiac disease is diagnosed by documenting and handling the electrocardiogram (ECG impulses. In the recent years many research has been done and developing an enhanced method to identify the risk in the patient’s body condition by processing and analysing the ECG signal. This analysis of the signal helps to find the cardiac abnormalities, arrhythmias, and many other heart problems. ECG signal is processed to detect the variability in heart rhythm; heart rate variability is calculated based on the time interval between heart beats. Heart Rate Variability HRV is measured by the variation in the beat to beat interval. The Heart rate Variability (HRV is an essential aspect to diagnose the properties of the heart. Recent development enhances the potential with the aid of non-linear metrics in reference point with feature selection. In this paper, the fundamental elements are taken from the ECG signal for feature selection process where Bat algorithm is employed for feature selection to predict the best feature and presented to the classifier for accurate classification. The popular machine learning algorithm ELM is taken for classification, integrated with evolutionary algorithm named Self- Adaptive Differential Evolution Extreme Learning Machine SADEELM to improve the reliability of classification. It combines Effective Fuzzy Kohonen clustering network (EFKCN to be able to increase the accuracy of the effect for HRV transmission classification. Hence, it is observed that the experiment carried out unveils that the precision is improved by the SADE-ELM method and concurrently optimizes the computation time.

Bluetooth Heart Rate Monitors For Spaceflight

Science.gov (United States)

Buxton, R. E.; West, M. R.; Kalogera, K. L.; Hanson, A. M.

2016-01-01

Heart rate monitoring is required for crewmembers during exercise aboard the International Space Station (ISS) and will be for future exploration missions. The cardiovascular system must be sufficiently stressed throughout a mission to maintain the ability to perform nominal and contingency/emergency tasks. High quality heart rate data are required to accurately determine the intensity of exercise performed by the crewmembers and show maintenance of VO2max. The quality of the data collected on ISS is subject to multiple limitations and is insufficient to meet current requirements. PURPOSE: To evaluate the performance of commercially available Bluetooth heart rate monitors (BT_HRM) and their ability to provide high quality heart rate data to monitor crew health aboard the ISS and during future exploration missions. METHODS: Nineteen subjects completed 30 data collection sessions of various intensities on the treadmill and/or cycle. Subjects wore several BT_HRM technologies for each testing session. One electrode-based chest strap (CS) was worn, while one or more optical sensors (OS) were worn. Subjects were instrumented with a 12-lead ECG to compare the heart rate data from the Bluetooth sensors. Each BT_HRM data set was time matched to the ECG data and a +/-5bpm threshold was applied to the difference between the 2 data sets. Percent error was calculated based on the number of data points outside the threshold and the total number of data points. RESULTS: The electrode-based chest straps performed better than the optical sensors. The best performing CS was CS1 (1.6% error), followed by CS4 (3.3% error), CS3 (6.4% error), and CS2 (9.2% error). The OS resulted in 10.4% error for OS1 and 14.9% error for OS2. CONCLUSIONS: The highest quality data came from CS1, but unfortunately it has been discontinued by the manufacturer. The optical sensors have not been ruled out for use, but more investigation is needed to determine how to obtain the best quality data. CS2 will be

The relationship between body temperature, heart rate, breathing rate, and rate of oxygen consumption, in the tegu lizard (Tupinambis merianae) at various levels of activity.

Science.gov (United States)

Piercy, Joanna; Rogers, Kip; Reichert, Michelle; Andrade, Denis V; Abe, Augusto S; Tattersall, Glenn J; Milsom, William K

2015-12-01

The present study determined whether EEG and/or EMG recordings could be used to reliably define activity states in the Brazilian black and white tegu lizard (Tupinambis merianae) and then examined the interactive effects of temperature and activity states on strategies for matching O2 supply and demand. In a first series of experiments, the rate of oxygen consumption (VO2), breathing frequency (fR), heart rate (fH), and EEG and EMG (neck muscle) activity were measured in different sleep/wake states (sleeping, awake but quiet, alert, or moving). In general, metabolic and cardio-respiratory changes were better indictors of the transition from sleep to wake than were changes in the EEG and EMG. In a second series of experiments, the interactive effects of temperature (17, 27 and 37 °C) and activity states on fR, tidal volume (VT), the fraction of oxygen extracted from the lung per breath (FIO2-FEO2), fH, and the cardiac O2 pulse were quantified to determine the relative roles of each of these variables in accommodating changes in VO2. The increases in oxygen supply to meet temperature- and activity-induced increases in oxygen demand were produced almost exclusively by increases in fH and fR. Regression analysis showed that the effects of temperature and activity state on the relationships between fH, fR and VO2 was to extend a common relationship along a single curve, rather than separate relationships for each metabolic state. For these lizards, the predictive powers of fR and fH were maximized when the effects of changes in temperature, digestive state and activity were pooled. However, the best r(2) values obtained were 0.63 and 0.74 using fR and fH as predictors of metabolic rate, respectively.

Intrapartum fetal heart rate profiles with and without fetal asphyxia.

Science.gov (United States)

Low, J A; Pancham, S R; Worthington, D N

1977-04-01

Fetal heart rate profiles for periods up to 12 hours prior to delivery have been reviewed in 515 patients with a fetus at risk. Mechanisms other than fetal asphyxia will cause fetal heart rate decelerations, and fetal asphyxia may in some instances develop in the absence of total or late decelerations. However, an increasing incidence of total decelerations and late decelerations and particularly a marked pattern of total decelerations and late decelerations are of value in the prediction of fetal asphyxia. Fetal heart rate deceleration patterns can predict the probability of fetal asphyxia at the time of initial intervention, while a progression of fetal heart rate deceleration patterns in the individual fetus can be of assistance in the subsequent scheduling of serial acid-base assessments during labor.

Spatially resolved RNA-sequencing of the embryonic heart identifies a role for Wnt/β-catenin signaling in autonomic control of heart rate

Science.gov (United States)

Burkhard, Silja Barbara

2018-01-01

Development of specialized cells and structures in the heart is regulated by spatially -restricted molecular pathways. Disruptions in these pathways can cause severe congenital cardiac malformations or functional defects. To better understand these pathways and how they regulate cardiac development we used tomo-seq, combining high-throughput RNA-sequencing with tissue-sectioning, to establish a genome-wide expression dataset with high spatial resolution for the developing zebrafish heart. Analysis of the dataset revealed over 1100 genes differentially expressed in sub-compartments. Pacemaker cells in the sinoatrial region induce heart contractions, but little is known about the mechanisms underlying their development. Using our transcriptome map, we identified spatially restricted Wnt/β-catenin signaling activity in pacemaker cells, which was controlled by Islet-1 activity. Moreover, Wnt/β-catenin signaling controls heart rate by regulating pacemaker cellular response to parasympathetic stimuli. Thus, this high-resolution transcriptome map incorporating all cell types in the embryonic heart can expose spatially restricted molecular pathways critical for specific cardiac functions. PMID:29400650

Relative influence of age, resting heart rate and sedentary life style in short-term analysis of heart rate variability

OpenAIRE

E.R. Migliaro; P. Contreras; S. Bech; A. Etxagibel; M. Castro; R. Ricca; K. Vicente

2001-01-01

In order to assess the relative influence of age, resting heart rate (HR) and sedentary life style, heart rate variability (HRV) was studied in two different groups. The young group (YG) consisted of 9 sedentary subjects aged 15 to 20 years (YG-S) and of 9 nonsedentary volunteers (YG-NS) also aged 15 to 20. The elderly sedentary group (ESG) consisted of 16 sedentary subjects aged 39 to 82 years. HRV was assessed using a short-term procedure (5 min). R-R variability was calculated in the time-...

The effects of sustained manual pressure stimulation according to Vojta Therapy on heart rate variability.

Science.gov (United States)

Opavsky, Jaroslav; Slachtova, Martina; Kutin, Miroslav; Hok, Pavel; Uhlir, Petr; Opavska, Hana; Hlustik, Petr

2018-05-23

The physiotherapeutic technique of Vojta reflex locomotion is often accompanied by various autonomic activity changes and unpleasant sensations. It is unknown whether these effects are specific to Vojta Therapy. Therefore, the aim of this study was to compare changes in cardiac autonomic control after Vojta reflex locomotion stimulation and after an appropriate sham stimulation. A total of 28 young healthy adults (20.4 - 25.7 years) were enrolled in this single-blind randomized cross-over study. Participants underwent two modes of 20-minute sustained manual pressure stimulation on the surface of the foot on two separate visits. One mode used manual pressure on the lateral heel, i.e., in a zone employed in the Vojta Therapy (active stimulation). The other mode used pressure on the lateral ankle (control), in an area not included among the active zones used by Vojta Therapy and whose activation does not evoke manifestations of reflex locomotion. Autonomic nervous system activity was evaluated using spectral analysis of heart rate variability before and after the intervention. The active stimulation was perceived as more unpleasant than the control stimulation. Heart rate variability parameters demonstrated almost identical autonomic responses after both stimulation types, showing either modest increase in parasympathetic activity, or increased heart rate variability with similar contribution of parasympathetic and sympathetic activity. The results demonstrate changes of cardiac autonomic control in both active and control stimulation, without evidence for a significant difference between the two.

Heart-Rate Variability—More than Heart Beats?

Directory of Open Access Journals (Sweden)

Gernot Ernst

2017-09-01

Full Text Available Heart-rate variability (HRV is frequently introduced as mirroring imbalances within the autonomous nerve system. Many investigations are based on the paradigm that increased sympathetic tone is associated with decreased parasympathetic tone and vice versa. But HRV is probably more than an indicator for probable disturbances in the autonomous system. Some perturbations trigger not reciprocal, but parallel changes of vagal and sympathetic nerve activity. HRV has also been considered as a surrogate parameter of the complex interaction between brain and cardiovascular system. Systems biology is an inter-disciplinary field of study focusing on complex interactions within biological systems like the cardiovascular system, with the help of computational models and time series analysis, beyond others. Time series are considered surrogates of the particular system, reflecting robustness or fragility. Increased variability is usually seen as associated with a good health condition, whereas lowered variability might signify pathological changes. This might explain why lower HRV parameters were related to decreased life expectancy in several studies. Newer integrating theories have been proposed. According to them, HRV reflects as much the state of the heart as the state of the brain. The polyvagal theory suggests that the physiological state dictates the range of behavior and psychological experience. Stressful events perpetuate the rhythms of autonomic states, and subsequently, behaviors. Reduced variability will according to this theory not only be a surrogate but represent a fundamental homeostasis mechanism in a pathological state. The neurovisceral integration model proposes that cardiac vagal tone, described in HRV beyond others as HF-index, can mirror the functional balance of the neural networks implicated in emotion–cognition interactions. Both recent models represent a more holistic approach to understanding the significance of HRV.

Heart-Rate Variability-More than Heart Beats?

Science.gov (United States)

Ernst, Gernot

2017-01-01

Heart-rate variability (HRV) is frequently introduced as mirroring imbalances within the autonomous nerve system. Many investigations are based on the paradigm that increased sympathetic tone is associated with decreased parasympathetic tone and vice versa . But HRV is probably more than an indicator for probable disturbances in the autonomous system. Some perturbations trigger not reciprocal, but parallel changes of vagal and sympathetic nerve activity. HRV has also been considered as a surrogate parameter of the complex interaction between brain and cardiovascular system. Systems biology is an inter-disciplinary field of study focusing on complex interactions within biological systems like the cardiovascular system, with the help of computational models and time series analysis, beyond others. Time series are considered surrogates of the particular system, reflecting robustness or fragility. Increased variability is usually seen as associated with a good health condition, whereas lowered variability might signify pathological changes. This might explain why lower HRV parameters were related to decreased life expectancy in several studies. Newer integrating theories have been proposed. According to them, HRV reflects as much the state of the heart as the state of the brain. The polyvagal theory suggests that the physiological state dictates the range of behavior and psychological experience. Stressful events perpetuate the rhythms of autonomic states, and subsequently, behaviors. Reduced variability will according to this theory not only be a surrogate but represent a fundamental homeostasis mechanism in a pathological state. The neurovisceral integration model proposes that cardiac vagal tone, described in HRV beyond others as HF-index, can mirror the functional balance of the neural networks implicated in emotion-cognition interactions. Both recent models represent a more holistic approach to understanding the significance of HRV.

Heart rate variability analysis in acute poisoning by cholinesterase inhibitors

OpenAIRE

JEONG, JINWOO; KIM, YONGIN

2017-01-01

Heart rate variability (HRV) has been associated with a variety of clinical situations. However, few studies have examined the association between HRV and acute poisoning. Organophosphate (OP) and carbamate inhibit esterase enzymes, particularly acetylcholinesterase, resulting in an accumulation of acetylcholine and thereby promoting excessive activation of corresponding receptors. Because diagnosis and treatment of OP and carbamate poisoning greatly depend on...

Changes of heart rate variability and prefrontal oxygenation during Tai Chi practice versus arm ergometer cycling.

Science.gov (United States)

Lu, Xi; Hui-Chan, Christina Wan-Ying; Tsang, William Wai-Nam

2016-11-01

[Purpose] Exercise has been shown to improve cardiovascular fitness and cognitive function. Whether the inclusion of mind over exercise would increase parasympathetic control of the heart and brain activities more than general exercise at a similar intensity is not known. The aim of this study was to compare the effects of Tai Chi (mind-body exercise) versus arm ergometer cycling (body-focused exercise) on the heart rate variability and prefrontal oxygenation level. [Subjects and Methods] A Tai Chi master was invited to perform Tai Chi and arm ergometer cycling with similar exercise intensity on two separate days. Heart rate variability and prefrontal oxyhemoglobin levels were measured continuously by a RR recorder and near-infrared spectroscopy, respectively. [Results] During Tai Chi exercise, spectral analysis of heart rate variability demonstrated a higher high-frequency power as well as a lower low-frequency/high-frequency ratio than during ergometer cycling, suggesting increased parasympathetic and decreased sympathetic control of the heart. Also, prefrontal oxyhemoglobin and total hemoglobin levels were higher than those during arm ergometer exercise. [Conclusion] These findings suggest that increased parasympathetic control of the heart and prefrontal activities may be associated with Tai Chi practice. Having a "mind" component in Tai Chi could be more beneficial for older adults' cardiac health and cognitive function than body-focused ergometer cycling.

Using Complexity Metrics With R-R Intervals and BPM Heart Rate Measures

DEFF Research Database (Denmark)

Wallot, Sebastian; Fusaroli, Riccardo; Tylén, Kristian

2013-01-01

Lately, growing attention in the health sciences has been paid to the dynamics of heart rate as indicator of impending failures and for prognoses. Likewise, in social and cognitive sciences, heart rate is increasingly employed as a measure of arousal, emotional engagement and as a marker of inter......Lately, growing attention in the health sciences has been paid to the dynamics of heart rate as indicator of impending failures and for prognoses. Likewise, in social and cognitive sciences, heart rate is increasingly employed as a measure of arousal, emotional engagement and as a marker...... of interpersonal coordination. However, there is no consensus about which measurements and analytical tools are most appropriate in mapping the temporal dynamics of heart rate and quite different metrics are reported in the literature. As complexity metrics of heart rate variability depend critically...

Inhibition of sarcoplasmic reticulum Ca(2+)-ATPase decreases atrioventricular node-paced heart rate in rabbits.

Science.gov (United States)

Cheng, Hongwei; Smith, Godfrey L; Orchard, Clive H; Hancox, Jules C; Burton, Francis L

2012-10-01

Recent data indicate that Ca(2+) cycling in isolated atrioventricular node (AVN) cells contributes to setting spontaneous rate. The aim of the present study was to extend this observation to the intact AVN in situ, by evaluating the effects of inhibiting sarcoplasmic reticulum Ca(2+) uptake with cyclopiazonic acid (CPA) on intact AVN spontaneous activity and its response to isoprenaline. A model of the AVN-paced heart was produced to investigate intact AVN automaticity, by surgical ablation of the sino-atrial node (SAN) in the rabbit Langendorff-perfused heart. Electrograms were recorded from a site close to the AVN (triangle of Koch), an atrial site above the AVN, the left atrium and right ventricle, enabling AVN pacing of the preparation to be confirmed. Before SAN ablation, the heart rate was 166.8 ± 5.4 beats min(-1). Ablation of the SAN was clearly indicated by a sudden and significant decrease of heart rate to 108.6 ± 9.6 beats min(-1) (P AVN rate to 187.8 ± 12.0 beats min(-1) after 1 min of application (P AVN rate to 81.6 ± 4.8 (n = 9) and 77.4 ± 6.0 beats min(-1) (n = 7), respectively [P AVN rate increase in response to isoprenaline from 78.8 ± 10.0 to 46.8 ± 6.8 and 26.7 ± 5.3%, respectively (P AVN rate and its response to isoprenaline indicate that Ca(2+) cycling is important to the intact AVN spontaneous activity and its acceleration during sympathetic stimulation.

Heart rate and flow velocity variability as determined from umbilical Doppler velocimetry at 10-20 weeks of gestation.

Science.gov (United States)

Ursem, N T; Struijk, P C; Hop, W C; Clark, E B; Keller, B B; Wladimiroff, J W

1998-11-01

1. The aim of this study was to define from umbilical artery flow velocity waveforms absolute peak systolic and time-averaged velocity, fetal heart rate, fetal heart rate variability and flow velocity variability, and the relation between fetal heart rate and velocity variables in early pregnancy.2.A total of 108 women presenting with a normal pregnancy from 10 to 20 weeks of gestation consented to participate in a cross-sectional study design. Doppler ultrasound recordings were made from the free-floating loop of the umbilical cord.3. Umbilical artery peak systolic and time-averaged velocity increased at 10-20 weeks, whereas fetal heart rate decreased at 10-15 weeks of gestation and plateaued thereafter. Umbilical artery peak systolic velocity variability and fetal heart rate variability increased at 10-20 and 15-20 weeks respectively.4. The inverse relationship between umbilical artery flow velocity and fetal heart rate at 10-15 weeks of gestation suggests that the Frank-Starling mechanism regulates cardiovascular control as early as the late first and early second trimesters of pregnancy. A different underlying mechanism is suggested for the observed variability profiles in heart rate and umbilical artery peak systolic velocity. It is speculated that heart rate variability is mediated by maturation of the parasympathetic nervous system, whereas peak systolic velocity variability reflects the activation of a haemodynamic feedback mechanism.

Mercury Exposure and Heart Rate Variability: A Systematic Review

Science.gov (United States)

Gribble, Matthew O.; Cheng, Alan; Berger, Ronald D.; Rosman, Lori; Guallar, Eliseo

2015-01-01

Background Mercury affects the nervous system and has been implicated in altering heart rhythm and function. We sought to better define its role in modulating heart rate variability, a well-known marker of cardiac autonomic function. Design Systematic review. Methods We searched PubMed, Embase, TOXLINE and DART databases without language restriction. We report findings as a qualitative systematic review because heterogeneity in study design and assessment of exposures and outcomes across studies, as well as other methodological limitations of the literature, precluded a quantitative meta-analysis. Results We identified 12 studies of mercury exposure and heart rate variability in human populations (10 studies involving primarily environmental methylmercury exposure and two studies involving occupational exposure to inorganic mercury) conducted in Japan, the Faroe Islands, Canada, Korea, French Polynesia, Finland and Egypt. The association of prenatal mercury exposure with lower high-frequency band scores (thought to reflect parasympathetic activity) in several studies, in particular the inverse association of cord blood mercury levels with the coefficient of variation of the R-R intervals and with low frequency and high frequency bands at 14 years of age in the Faroe Islands birth cohort study, suggests that early mercury exposure could have a long-lasting effect on cardiac parasympathetic activity. Studies with later environmental exposures to mercury in children or in adults were heterogeneous and did not show consistent associations. Conclusions The evidence was too limited to draw firm causal inferences. Additional research is needed to elucidate the effects of mercury on cardiac autonomic function, particularly as early-life exposures might have lasting impacts on cardiac parasympathetic function. PMID:26231507

Heart rate variability changes in business process outsourcing employees working in shifts.

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Kunikullaya, Kirthana U; Kirthi, Suresh K; Venkatesh, D; Goturu, Jaisri

2010-10-31

Irregular and poor quality sleep is common in business process outsourcing (BPO) employees due to continuous shift working. The influence of this on the cardiac autonomic activity was investigated by the spectral analysis of heart rate variability (HRV). 36 night shift BPO employees (working from 22:00 to 06:00h) and 36 age and sex matched day shift BPO employees (working from 08:00 to 16:00h) were recruited for the study. Five minute electrocardiogram (ECG) was recorded in all the subjects. Heart rate variability was analyzed by fast Fourier transformation using RMS Vagus HRV software. The results were analyzed using Mann Whitney U test, Student t-test, Wilcoxon signed rank test and were expressed as mean ± SD. Sleepiness was significantly higher among night shift workers as measured by Epworth Sleepiness Scale (p<0.001). Night shift BPO employees were found to have a trend towards lower values of vagal parameters - HF power (ms(2)), and higher values of sympathovagal parameters like LF Power (ms(2)) and the LF/HF power (%) suggesting decreased vagal activity and sympathetic over activity, when compared to day shift employees. However, HRV parameters did not vary significantly between the day shift employees and night shift workers baseline values, and also within the night shift group. Night shift working increased the heart rate and shifted the sympathovagal balance towards sympathetic dominance and decreased vagal parameters of HRV. This is an indicator of unfavorable change in the myocardial system, and thus shows increased risk of cardiovascular disease among the night shift employees.

Diminution of Heart Rate Variability in Bipolar Depression

Directory of Open Access Journals (Sweden)

Brandon Hage

2017-12-01

Full Text Available Autonomic nervous system (ANS dysregulation in depression is associated with symptoms associated with the ANS. The beat-to-beat pattern of heart rate defined as heart rate variability (HRV provides a noninvasive portal to ANS function and has been proposed to represent a means of quantifying resting vagal tone. We quantified HRV in bipolar depressed (BDD patients as a measure of ANS dysregulation seeking to establish HRV as a potential diagnostic and prognostic biomarker for treatment outcome. Forty-seven BDD patients were enrolled. They were randomized to receive either escitalopram–celecoxib or escitalopram-placebo over 8 weeks in a double-blind study design. Thirty-five patients completed the HRV studies. Thirty-six healthy subjects served as controls. HRV was assessed at pretreatment and end of study and compared with that of controls. HRV was quantified and corrected for artifacts using an algorithm that incorporates time and frequency domains to address non-stationarity of the beat-to-beat heart rate pattern. Baseline high frequency-HRV (i.e., respiratory sinus arrhythmia was lower in BDD patients than controls, although the difference did not reach significance. Baseline low-frequency HRV was significantly lower in BDD patients (ln4.20 than controls (ln = 5.50 (p < 0.01. Baseline heart period was significantly shorter (i.e., faster heart rate in BDD patients than controls. No significant change in HRV parameters were detected over the course of the study with either treatment. These findings suggest that components of HRV may be diminished in BDD patients.

The modulatory effects of noradrenaline on vagal control of heart rate in the dogfish, Squalus acanthias.

Science.gov (United States)

Agnisola, Claudio; Randall, David J; Taylor, Edwin W

2003-01-01

The possible interactions between inhibitory vagal control of the heart and circulating levels of catecholamines in dogfish (Squalus acanthias) were studied using an in situ preparation of the heart, which retained intact its innervation from centrally cut vagus nerves. The response to peripheral vagal stimulation typically consisted of an initial cardiac arrest, followed by an escape beat, leading to renewed beating at a mean heart rate lower than the prestimulation rate (partial recovery). Cessation of vagal stimulation led to a transient increase in heart rate, above the prestimulation rate. This whole response was completely abolished by 10(-4) M atropine (a muscarinic cholinergic antagonist). The degree of vagal inhibition was evaluated in terms of both the initial, maximal cardiac interval and the mean heart rate during partial recovery, both expressed as a percentage of the prestimulation heart rate. The mean prestimulation heart rate of this preparation (36+/-4 beats min(-1)) was not affected by noradrenaline but was significantly reduced by 10(-4) M nadolol (a beta-adrenergic receptor antagonist), suggesting the existence of a resting adrenergic tone arising from endogenous catecholamines. The degree of vagal inhibition of heart rate varied with the rate of stimulation and was increased by the presence of 10(-8) M noradrenaline (the normal in vivo level in routinely active fish), while 10(-7) M noradrenaline (the in vivo level measured in disturbed or deeply hypoxic fish) reduced the cardiac response to vagal stimulation. In the presence of 10(-7) M noradrenaline, 10(-4) M nadolol further reduced the vagal response, while 10(-4) M nadolol + 10(-4) M phentolamine had no effect, indicating a complex interaction between adrenoreceptors, possibly involving presynaptic modulation of vagal inhibition.

Modeling baroreflex regulation of heart rate during orthostatic stress

DEFF Research Database (Denmark)

Olufsen, Mette; Tran, Hien T.; Ottesen, Johnny T.

2006-01-01

. The model uses blood pressure measured in the finger as an input to model heart rate dynamics in response to changes in baroreceptor nerve firing rate, sympathetic and parasympathetic responses, vestibulo-sympathetic reflex, and concentrations of norepinephrine and acetylcholine. We formulate an inverse...... in healthy and hypertensive elderly people the hysteresis loop shifts to higher blood pressure values and its area is diminished. Finally, for hypertensive elderly people the hysteresis loop is generally not closed indicating that during postural change from sitting to standing, the blood pressure resettles......During orthostatic stress, arterial and cardiopulmonary baroreflexes play a key role in maintaining arterial pressure by regulating heart rate. This study, presents a mathematical model that can predict the dynamics of heart rate regulation in response to postural change from sitting to standing...

Heart rate variability affected by radiofrequency electromagnetic field in adolescent students.

Science.gov (United States)

Misek, Jakub; Belyaev, Igor; Jakusova, Viera; Tonhajzerova, Ingrid; Barabas, Jan; Jakus, Jan

2018-05-01

This study examines the possible effect of radiofrequency (RF) electromagnetic fields (EMF) on the autonomic nervous system (ANS). The effect of RF EMF on ANS activity was studied by measuring heart rate variability (HRV) during ortho-clinostatic test (i.e., transition from lying to standing and back) in 46 healthy grammar school students. A 1788 MHz pulsed wave with intensity of 54 ± 1.6 V/m was applied intermittently for 18 min in each trial. Maximum specific absorption rate (SAR 10 ) value was determined to 0.405 W/kg. We also measured the respiration rate and estimated a subjective perception of EMF exposure. RF exposure decreased heart rate of subjects in a lying position, while no such change was seen in standing students. After exposure while lying, a rise in high frequency band of HRV and root Mean Square of the Successive Differences was observed, which indicated an increase in parasympathetic nerve activity. Tympanic temperature and skin temperature were measured showing no heating under RF exposure. No RF effect on respiration rate was observed. None of the tested subjects were able to distinguish real exposure from sham exposure when queried at the end of the trial. In conclusion, short-term RF EMF exposure of students in a lying position during the ortho-clinostatic test affected ANS with significant increase in parasympathetic nerve activity compared to sham exposed group. Bioelectromagnetics. 39:277-288, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Validation of an Internet-Based Long Version of the International Physical Activity Questionnaire in Danish Adults Using Combined Accelerometry and Heart Rate Monitoring

DEFF Research Database (Denmark)

Hansen, Andreas Wolff; Dahl-Petersen, Inger; Helge, Jørn Wulff

2014-01-01

a unit that combined accelerometry and heart rate monitoring (Acc+HR) for 7 consecutive days and then completed the IPAQ. Background data were obtained from the survey. Physical activity energy expenditure (PAEE) and time in moderate, vigorous and sedentary intensity level were derived from the IPAQ...

Relationship between heart rate and preference for tempo of music.

Science.gov (United States)

Iwanaga, M

1995-10-01

People prefer music with tempi ranging from 70 to 100 cycles per minute similar to that of adults' heart rate within normal daily situations. Previous studies of the relation between preferred tempi and heart rates using a pure tone also have indicated that subjects tended to prefer tempi similar to their heart rates. The present study examined this relationship using a musical piece (the theme of "It's a small world") as a stimulus. 14 undergraduate women were subjects who searched for their favorite tempi by controlling the musical tempo by themselves. The most preferred tempo was close to their cycle of heart beats, however, tempi that were one and a half and twice as fast as the heart rate were less preferred in the present study than in a previous study using a tone. Subjects preferred faster tempi in the descending series of stimuli than in the ascending one, and hence were influenced by the initial value of the tempo in the trial sequence. The effects due to the differences of the meaning of the stimuli are considered.

Relative influence of age, resting heart rate and sedentary life style in short-term analysis of heart rate variability

Directory of Open Access Journals (Sweden)

E.R. Migliaro

2001-04-01

Full Text Available In order to assess the relative influence of age, resting heart rate (HR and sedentary life style, heart rate variability (HRV was studied in two different groups. The young group (YG consisted of 9 sedentary subjects aged 15 to 20 years (YG-S and of 9 nonsedentary volunteers (YG-NS also aged 15 to 20. The elderly sedentary group (ESG consisted of 16 sedentary subjects aged 39 to 82 years. HRV was assessed using a short-term procedure (5 min. R-R variability was calculated in the time-domain by means of the root mean square successive differences. Frequency-domain HRV was evaluated by power spectrum analysis considering high frequency and low frequency bands. In the YG the effort tolerance was ranked in a bicycle stress test. HR was similar for both groups while ESG showed a reduced HRV compared with YG. Within each group, HRV displayed a negative correlation with HR. Although YG-NS had better effort tolerance than YG-S, their HR and HRV were not significantly different. We conclude that HRV is reduced with increasing HR or age, regardless of life style. The results obtained in our short-term study agree with others of longer duration by showing that age and HR are the main determinants of HRV. Our results do not support the idea that changes in HRV are related to regular physical activity.

Relative influence of age, resting heart rate and sedentary life style in short-term analysis of heart rate variability.

Science.gov (United States)

Migliaro, E R; Contreras, P; Bech, S; Etxagibel, A; Castro, M; Ricca, R; Vicente, K

2001-04-01

In order to assess the relative influence of age, resting heart rate (HR) and sedentary life style, heart rate variability (HRV) was studied in two different groups. The young group (YG) consisted of 9 sedentary subjects aged 15 to 20 years (YG-S) and of 9 nonsedentary volunteers (YG-NS) also aged 15 to 20. The elderly sedentary group (ESG) consisted of 16 sedentary subjects aged 39 to 82 years. HRV was assessed using a short-term procedure (5 min). R-R variability was calculated in the time-domain by means of the root mean square successive differences. Frequency-domain HRV was evaluated by power spectrum analysis considering high frequency and low frequency bands. In the YG the effort tolerance was ranked in a bicycle stress test. HR was similar for both groups while ESG showed a reduced HRV compared with YG. Within each group, HRV displayed a negative correlation with HR. Although YG-NS had better effort tolerance than YG-S, their HR and HRV were not significantly different. We conclude that HRV is reduced with increasing HR or age, regardless of life style. The results obtained in our short-term study agree with others of longer duration by showing that age and HR are the main determinants of HRV. Our results do not support the idea that changes in HRV are related to regular physical activity.

The heart rate response to nintendo wii boxing in young adults.

Science.gov (United States)

Bosch, Pamela R; Poloni, Joseph; Thornton, Andrew; Lynskey, James V

2012-06-01

To determine if 30 minutes of Nintendo Wii Sports boxing provides cardiorespiratory benefits and contributes to the daily exercise recommendations for healthy young adults. Twenty healthy 23- to 27-year-olds participated in two sessions to measure maximum heart rate (HR(max)) via a treadmill test and heart rate (HR) response to 30 minutes of Wii Sports boxing. Heart rate in beats per minute (bpm) was measured continuously, and exercise intensity during each minute of play was stratified as a percentage of HR(max). Mixed designs analysis of variance (ANOVA) and Pearson product moment correlations were used to analyze the data. Mean (SD) HR response to boxing was 143 (15) bpm or 77.5% (10.0%) of HR(max). The mean HR response for experienced participants was significantly lower than inexperienced participants, P = .007. The ANOVA revealed a significant interaction between experience and time spent at various intensities, P = .009. Experienced participants spent more time in light to vigorous intensities, inexperienced participants in moderate to very hard intensities. Fitness was not correlated with mean HR response to boxing, P = .49. Thirty minutes of Nintendo Wii Sports boxing provides a moderate to vigorous aerobic response in healthy young adults and can contribute to daily recommendations for physical activity.

Do high fetal catecholamine levels affect heart rate variability and ...

African Journals Online (AJOL)

Objectives. To deternrine the relationship between Umbilical arterial catecholamine levels and fetal heart rate variability and meconium passage. Study design. A prospective descriptive study was perfonned. Umbilical artery catecholamine levels were measured in 55 newborns and correlated with fetal heart rate before ...

Fetal Heart Rate Monitoring during Labor

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... What are the types of monitoring? • How is auscultation performed? • How is electronic fetal monitoring performed? • How ... methods of fetal heart rate monitoring in labor. Auscultation is a method of periodically listening to the ...

Measuring acute changes in adrenergic nerve activity of the heart in the living animal

International Nuclear Information System (INIS)

Sisson, J.C.; Bolgos, G.; Johnson, J.

1991-01-01

Changes in the function of the adrenergic neurons of the heart may be important indicators of the adaptations of an animal to physiologic stress and disease. Rates of loss of norepinephrine (NE) from the heart were considered to be proportional to NE secretion and to adrenergic function. In rat hearts, yohimbine induced almost identical increases in rates of loss of 3 H-NE and of 125 I-metaiodobenzylguanidine (MIBG), a functional analog of NE. Clonidine induced decreases in rates of loss of 3 H-NE that were also mimicked by those of 125 I-MIBG. In the dog heart, pharmacologically-induced increases and decreases in rates of loss of 123 I-MIBG could be measured externally; these values were similar to those obtained for 125 I-MIBG in the rat heart. Thus acute changes in the adrenergic neuron activity can be measured in the living heart. The method is applicable to man in determining the capacity of the adrenergic system to respond to provocative challenges

A healthy heart is not a metronome: An integrative review of the heart’s anatomy and heart rate variability

Directory of Open Access Journals (Sweden)

Fredric Bruce Shaffer

2014-09-01

Full Text Available Heart rate variability (HRV, the change in the time intervals between adjacent heartbeats, is an emergent property of interdependent regulatory systems that operate on different time scales to adapt to challenges and achieve optimal performance. This article briefly reviews neural regulation of the heart, and its basic anatomy, the cardiac cycle, and the sinoatrial and atrioventricular pacemakers. The cardiovascular regulation center in the medulla integrates sensory information and input from higher brain centers, and afferent cardiovascular system inputs to adjust heart rate and blood pressure via sympathetic and parasympathetic efferent pathways. This article reviews sympathetic and parasympathetic influences on the heart, and examines the interpretation of HRV and the association between reduced HRV, risk of disease and mortality, and the loss of regulatory capacity. This article also discusses the intrinsic cardiac nervous system and the heart-brain connection, through which afferent information can influence activity in the subcortical and frontocortical areas, and motor cortex. It also considers new perspectives on the putative underlying physiological mechanisms and properties of the ultra-low-frequency (ULF, very-low-frequency (VLF, low-frequency (LF, and high-frequency (HF bands. Additionally, it reviews the most common time and frequency domain measurements as well as standardized data collection protocols. In its final section, this article integrates Porges’ polyvagal theory, Thayer and colleagues’ neurovisceral integration model, Lehrer, Vaschillo, and Vaschillo’s resonance frequency model, and the Institute of HeartMath’s coherence model. The authors conclude that a coherent heart is not a metronome because its rhythms are characterized by both complexity and stability over longer time scales. Future research should expand understanding of how the heart and its intrinsic nervous system influence the brain.

Heart Rate Variability and Wavelet-based Studies on ECG Signals from Smokers and Non-smokers

Science.gov (United States)

Pal, K.; Goel, R.; Champaty, B.; Samantray, S.; Tibarewala, D. N.

2013-12-01

The current study deals with the heart rate variability (HRV) and wavelet-based ECG signal analysis of smokers and non-smokers. The results of HRV indicated dominance towards the sympathetic nervous system activity in smokers. The heart rate was found to be higher in case of smokers as compared to non-smokers ( p smokers from the non-smokers. The results indicated that when RMSSD, SD1 and RR-mean features were used concurrently a classification efficiency of > 90 % was achieved. The wavelet decomposition of the ECG signal was done using the Daubechies (db 6) wavelet family. No difference was observed between the smokers and non-smokers which apparently suggested that smoking does not affect the conduction pathway of heart.

Correlation of heart rate and radionuclide index of left ventricular contraction and relaxation

International Nuclear Information System (INIS)

Adachi, Haruhiko; Sugihara, Hiroki; Nakagawa, Hiroaki; Inagaki, Suetsugu; Kubota, Yasushi; Nakagawa, Masao

1990-01-01

Since the cardiac function indices derived from radionuclide ventriculography (RNV) are considered to depend on the heart rate, we studied the relationship between systolic or diastolic indices and heart rates in patients with normal RNV and devised a method of correcting these indices according to the heart rate. For the systolic indices, the heart rate showed significant correlation with ET (r=-0.640), PER (r=0.791) and TPE (r=-0.401) but not with EF, 1/3 EF, MNSER or 1/3 MNSER. For the diastolic indices, the heart rate correlated well with FT (r=-0.938), RFT (r=-0.736), SFT (r=-0.803), 1/3 FF (r=-0.758), PFR (r=0.759), 1/3 PFR (r=0.742) and TPF (r=-0.389) but not with AFT, 1/3 MNDFR or AFF. These results indicate that many systolic and diastolic indices derived from RNV are affected by the heart rate, So when cardiac function is evaluated with the use of radionuclide indices, those which are independent of the heart rate should be used, or they should be corrected for the heart rate. As a method of correction, we proposed a rotating method obtained by manipulation of the regression equation of heart rates and indices. This new method is certain and easier to use when the correcting equations are set into a computer program. (author)

AUTONOMIC CONTROL OF HEART RATE AFTER EXERCISE IN TRAINED WRESTLERS

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Carlos F Henríquez

2013-04-01

Full Text Available The objective of this study was to establish differences in vagal reactivation, through heart rate recovery and heart rate variability post exercise, in Brazilian jiu-jitsu wrestlers (BJJW. A total of 18 male athletes were evaluated, ten highly trained (HT and eight moderately trained (MT, who performed a maximum incremental test. At the end of the exercise, the R-R intervals were recorded during the first minute of recovery. We calculated heart rate recovery (HRR60s, and performed linear and non-linear (standard deviation of instantaneous beat-to-beat R-R interval variability – SD1 analysis of heart rate variability (HRV, using the tachogram of the first minute of recovery divided into four segments of 15 s each (0-15 s, 15-30 s, 30-45 s, 45-60 s. Between HT and MT individuals, there were statistically significant differences in HRR60s (p <0.05 and in the non linear analysis of HRV from SD130-45s (p <0.05 and SD145-60s (p <0.05. The results of this research suggest that heart rate kinetics during the first minute after exercise are related to training level and can be used as an index for autonomic cardiovascular control in BJJW.

Heart rate variability, sleep, and the early detection of post-traumatic stress disorder

NARCIS (Netherlands)

van Boxtel, Geert J.M.; Cluitmans, Pierre J.M.; Raymann, Roy J.E.M.; Ouwerkerk, Martin; Denissen, Ad J.M.; Dekker, Marian K.J.; Sitskoorn, Margriet M.; Vermetten, E.; Germain, A.; Neylan, T.C.

2017-01-01

Measures of heart rate variability (HRV) are sensitive indices of autonomic nervous system functioning, capable of distinguishing activity of its two constituent branches, the sympathetic and parasympathetic nervous systems. As such, these measures are possibly useful as early markers of

Design of heart rate monitor based on piezoelectric sensor using an Arduino

Science.gov (United States)

Setyowati, Veni; Muninggar, Jodelin; Shanti. N. A, Made R. S.

2017-01-01

Reading of result heart rate using an acoustic stethoscope needs a particular skill, quiet environment, and hearing sensitivity. This project had the purpose design of a user-friendly automatic heart rate monitor and especially in a noisy area which to eliminate problems and incorrect reading of result. The liquid crystal display shows a heart rate as a result of measurements. The design of the heart rate monitor has two main parts; the signal recorder that a piezoelectric sensor, a filter, and an amplifier as recorder. The second parts was Arduino microcontroller with reinforced. Besides, three supporting buttons provided as the manual switches, the ‘on’, the ‘start’, and ‘reset’ buttons. The values acquired from the heart rate monitor indicate that those were on the Vernier BPS-BTA value range. The measurement error factor of the heart rate monitor then compared to the Vernier BPS-BTA test device was 3.15%. Besides, the value of statistical independent-test indicates that there is no significant difference (P = 0.971) between the heart rate monitor device and the Vernier BPS-BTA. In conclusion, this device was ready to be used because it has almost the same accuracy with the standart device.

Physical Activity and Heart Rate Variability in Older Adults: The Cardiovascular Health Study

Science.gov (United States)

Soares-Miranda, Luisa; Sattelmair, Jacob; Chaves, Paulo; Duncan, Glen; Siscovick, David S; Stein, Phyllis K; Mozaffarian, Dariush

2014-01-01

Background Cardiac mortality and electrophysiologic dysfunction both increase with age. Heart rate variability (HRV) provides indices of autonomic function and electrophysiology that are associated with cardiac risk. How habitual physical activity (PA) among older adults prospectively relates to HRV, including nonlinear indices of erratic sinus patterns, is not established. We hypothesized that increasing levels of both total leisure-time activity and walking would be prospectively associated with more favorable time-domain, frequency-domain, and nonlinear HRV measures in older adults. Methods and Results We evaluated serial longitudinal measures of both PA and 24-hour Holter HRV over 5 years among 985 older US adults in the community-based Cardiovascular Health Study. After multivariable adjustment, greater total leisure-time activity, walking distance, and walking pace were each prospectively associated with specific, more favorable HRV indices, including higher 24-hour standard-deviation-of-all-normal-to-normal-intervals (SDNN, p-trend=0.009, 0.02, 0.06, respectively) and ultra-low-frequency-power (p-trend=0.02, 0.008, 0.16, respectively). Greater walking pace was also associated with higher short-term-fractal-scaling-exponent (p-trend=0.003) and lower Poincare ratio (p-trend=0.02), markers of less erratic sinus patterns. Conclusions Greater total leisure-time activity, as well as walking alone, were prospectively associated with more favorable and specific indices of autonomic function in older adults, including several suggestive of more normal circadian fluctuations and less erratic sinoatrial firing. Our results suggest potential mechanisms that might contribute to lower cardiovascular mortality with habitual PA later in life. PMID:24799513

[Voluntary alpha-power increasing training impact on the heart rate variability].

Science.gov (United States)

Bazanova, O M; Balioz, N V; Muravleva, K B; Skoraia, M V

2013-01-01

In order to study the effect of the alpha EEG power increasing training at heart rate variability (HRV) as the index of the autonomic regulation of cognitive functions there were follow tasks: (1) to figure out the impact of biofeedback in the voluntary increasing the power in the individual high-frequency alpha-band effect on heart rate variability and related characteristics of cognitive and emotional spheres, (2) to determine the nature of the relationship between alpha activity indices and heart rate variability, depending on the alpha-frequency EEG pattern at rest (3) to examine how the individual alpha frequency EEG pattern is reflected in changes HRV as a result of biofeedback training. Psychometric indicators of cognitive performance, the characteristics of the alpha-EEG activity and heart rate variability (HRV) as LF/HF and pNN50 were recorded in 27 healthy men aged 18-34 years, before, during, and after 10 sessions of training of voluntary increase in alpha power in the individual high-frequency alpha band with eyes closed. To determine the biofeedback effect on the alpha power increasing training, data subjects are compared in 2 groups: experimental (14) with the real and the control group (13 people)--with mock biofeedback. The follow up effect of trainings was studied through month over the 10 training sessions. Results showed that alpha biofeedback training enhanced the fluency and accuracy in cognitive performance, decreased anxiety and frontal EMG, increased resting frequency, width and power in individual upper alpha range only in participants with low baseline alpha frequency. While mock biofeedback increased resting alpha power only in participants with high baseline resting alpha frequency and did change neither cognitive performance, nor HRV indices. Biofeedback training eliminated the alpha power decrease in response to arithmetic task in both with high and low alpha frequency participants and this effect was followed up over the month. Mock

Heart rate variability in bipolar disorder

DEFF Research Database (Denmark)

Faurholt-Jepsen, Maria; Kessing, Lars Vedel; Munkholm, Klaus

2017-01-01

Background Heart rate variability (HRV) has been suggested reduced in bipolar disorder (BD) compared with healthy individuals (HC). This meta-analysis investigated: HRV differences in BD compared with HC, major depressive disorder or schizophrenia; HRV differences between affective states; HRV...

Effects of hot-iron branding on heart rate, breathing rate and behaviour of anaesthetised Steller sea lions.

Science.gov (United States)

Walker, K A; Mellish, J E; Weary, D M

2011-10-01

This study assessed the heart rate, breathing rate and behavioural responses of 12 juvenile Steller sea lions during hot-iron branding under isoflurane anaesthesia. Physiological and behavioural measures were recorded in four periods: baseline (five minutes), sham branding (one minute), branding (approximately 2.7 minutes) and postbranding (five minutes). No difference in heart rate was noted from baseline to sham branding, but heart rate increased from mean (sem) 78.3 (2.4) bpm in the baseline period to 85.6 (2.5) bpm in the branding period. Heart rate remained elevated in the postbranding period, averaging 84.7 (2.5) bpm. Breathing rate averaged 2.5 (1.0) breaths/minute in the baseline and sham branding periods increased to 8.9 (1.0) breaths/minute during branding, but returned to baseline by the postbranding period. Behaviourally, half of the sea lions exhibited trembling and head and shoulder movements during branding.

The clinical significance of detection to heart rate deceleration capacity and heart rate variability in patients with chronic heart failure

Directory of Open Access Journals (Sweden)

Jiang-rong Zhou

2015-01-01

Full Text Available Objective: To study the change of heart rate deceleration capacity ( DC and heart rate variability in patients with chronic heart failure (CHF and its relationship with left ventricular ejection fraction (LVEF. Methods: DC, LVEF, time and frequency domain parameters of HRV were measured in 66 patients with CHF and 34 healthy adults (control group by using 24h Holter recordings and Echocardiography. The standard deviation of normal R-R intervals( SDNN, squares of differences between adjacent NN intervals ( RMSSD，low frequency power( LFn and high frequency power( HFn and the changes of LVEF were compared between  the two groups，the relationship between DC，LVEF and HRV were studied in patients with CHF. Results: The median value of DC in the patients with CHF was significantly lower than that in control group( 3.1 ± 2.4 ms vs 7.2 ± 1.3 ms，P <0.01．Incidence of abnormal DC in the CHF group was 57.5%，which was significantly higher than that in the control group (P <0.01．The HRV index, including SDNN、RMSSD、LFn、HFn, in the CHF group was significantly lower than that in normal control group (P < 0.01. Significant positive correlation between HRV index and LVEF were confirmed (P < 0.01. Conclusions: DC and HRV index are lower in patients with CHF and have a good correlation with the left ventricular ejection fraction.

Heart Rate Variability Interventions for Concussion and Rehabilitation

Directory of Open Access Journals (Sweden)

Robert Lake Conder

2014-08-01

Full Text Available The study of Heart Rate Variability (HRV has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain. It is well-established that lack of heart rate variability implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal heart rate variability has been associated with good cardiovascular health, autonomic nervous system (ANS control, emotional regulation, and enhanced neurocognitive processing. In addition to health benefits, optimal HRV has been shown to improve neurocognitive performance by enhancing focus, visual acuity and readiness, and by promoting emotional regulation needed for peak performance. In concussed athletes and soldiers, concussions not only alter brain connectivity, but also alter cardiac functioning and impair cardiovascular performance upon exertion. Altered sympathetic and parasympathetic balance in the ANS has been postulated as a critical factor in refractory Post Concussive Syndrome (PCS. This article will review both the pathological aspects of reduced heart rate variability on athletic performance, as well as the cardiovascular and cerebrovascular components of concussion and PCS. Additionally, this article will review interventions with HRV biofeedback (HRV BFB training as a promising and underutilized treatment for sports and military-related concussion. Finally, this article will review research and promising case studies pertaining to use of HRV BFB for enhancement of cognition and performance, with applicability to concussion rehabilitation.

Being active when you have heart disease

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Heart disease - activity; CAD - activity; Coronary artery disease - activity; Angina - activity ... Getting regular exercise when you have heart disease is ... It may also help you be more active without chest pain or other ...

Novel Fingertip Image-Based Heart Rate Detection Methods for a Smartphone

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Rifat Zaman

2017-02-01

Full Text Available We hypothesize that our fingertip image-based heart rate detection methods using smartphone reliably detect the heart rhythm and rate of subjects. We propose fingertip curve line movement-based and fingertip image intensity-based detection methods, which both use the movement of successive fingertip images obtained from smartphone cameras. To investigate the performance of the proposed methods, heart rhythm and rate of the proposed methods are compared to those of the conventional method, which is based on average image pixel intensity. Using a smartphone, we collected 120 s pulsatile time series data from each recruited subject. The results show that the proposed fingertip curve line movement-based method detects heart rate with a maximum deviation of 0.0832 Hz and 0.124 Hz using time- and frequency-domain based estimation, respectively, compared to the conventional method. Moreover, another proposed fingertip image intensity-based method detects heart rate with a maximum deviation of 0.125 Hz and 0.03 Hz using time- and frequency-based estimation, respectively.

Comparison of structured and unstructured physical activity training on predicted VO2max and heart rate variability in adolescents - a randomized control trial.

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Sharma, Vivek Kumar; Subramanian, Senthil Kumar; Radhakrishnan, Krishnakumar; Rajendran, Rajathi; Ravindran, Balasubramanian Sulur; Arunachalam, Vinayathan

2017-05-01

Physical inactivity contributes to many health issues. The WHO-recommended physical activity for adolescents encompasses aerobic, resistance, and bone strengthening exercises aimed at achieving health-related physical fitness. Heart rate variability (HRV) and maximal aerobic capacity (VO2max) are considered as noninvasive measures of cardiovascular health. The objective of this study is to compare the effect of structured and unstructured physical training on maximal aerobic capacity and HRV among adolescents. We designed a single blinded, parallel, randomized active-controlled trial (Registration No. CTRI/2013/08/003897) to compare the physiological effects of 6 months of globally recommended structured physical activity (SPA), with that of unstructured physical activity (USPA) in healthy school-going adolescents. We recruited 439 healthy student volunteers (boys: 250, girls: 189) in the age group of 12-17 years. Randomization across the groups was done using age and gender stratified randomization method, and the participants were divided into two groups: SPA (n=219, boys: 117, girls: 102) and USPA (n=220, boys: 119, girls: 101). Depending on their training status and gender the participants in both SPA and USPA groups were further subdivided into the following four sub-groups: SPA athlete boys (n=22) and girls (n=17), SPA nonathlete boys (n=95) and girls (n=85), USPA athlete boys (n=23) and girls (n=17), and USPA nonathlete boys (n=96) and girls (n=84). We recorded HRV, body fat%, and VO2 max using Rockport Walk Fitness test before and after the intervention. Maximum aerobic capacity and heart rate variability increased significantly while heart rate, systolic blood pressure, diastolic blood pressure, and body fat percentage decreased significantly after both SPA and USPA intervention. However, the improvement was more in SPA as compared to USPA. SPA is more beneficial for improving cardiorespiratory fitness, HRV, and reducing body fat percentage in terms of

Determination of Hemodynamic Changes on Heart Rate for Assessment of Orthostatic Intolerance in Older People

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Hortelano Rubio, M.; Reilly, R.B.; Cervigón Abad, R.

2016-07-01

Introduction.- The aim of our study was to assess the hemodynamic changes that occur in symptomatic Orthostatic Intolerance (OI) patients, at the starting of exercise and recovery stages during six minutes walking distance test. Materials.- We analysed 65 older subjects, of whom 42 were women. The participants were carried out the Active Stand Protocol. The records were divided into: Phase 1 (pre-exercise), Phase 2 (starting of exercise), Phase 3 (active), Phase 4 (recovery) and Phase 5 (prost-exercise). Methods.- The averages and differences of heart rate (HR) between Phase 1, Phase 3 and Phase 5 were calculated. In the same way, duration before stabilization from passive to active stages (Phase 2) and from active to passive stages (Phase 4) were calculated. The máximum and mínimum values achieved in these time series and the difference between these values were also calculated. Results.- Results showed that the symptomatic OI patients employed more time to reach the active phase tan the asymptomatic OI participants. Moreover, the symptomatic OI participants showed higher mínimum heart rate values at the starting of exercise and recovery stages. However, the asymptomatic OI group illustrated a higher difference between the máximum and mínimum heart rate values in these stages with a significance p=0.003 and p=0.007, respectivecly. Conclusion.- This study provides important information on hemodynamic parameters and can be helpful for description of the hemodynamic changes that occur during OI. (Author)

Patterns of Interspecific Variation in the Heart Rates of Embryonic Reptiles

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Du, Wei-Guo; Ye, Hua; Zhao, Bo; Pizzatto, Ligia; Ji, Xiang; Shine, Richard

2011-01-01

New non-invasive technologies allow direct measurement of heart rates (and thus, developmental rates) of embryos. We applied these methods to a diverse array of oviparous reptiles (24 species of lizards, 18 snakes, 11 turtles, 1 crocodilian), to identify general influences on cardiac rates during embryogenesis. Heart rates increased with ambient temperature in all lineages, but (at the same temperature) were faster in lizards and turtles than in snakes and crocodilians. We analysed these data within a phylogenetic framework. Embryonic heart rates were faster in species with smaller adult sizes, smaller egg sizes, and shorter incubation periods. Phylogenetic changes in heart rates were negatively correlated with concurrent changes in adult body mass and residual incubation period among the lizards, snakes (especially within pythons) and crocodilians. The total number of embryonic heart beats between oviposition and hatching was lower in squamates than in turtles or the crocodilian. Within squamates, embryonic iguanians and gekkonids required more heartbeats to complete development than did embryos of the other squamate families that we tested. These differences plausibly reflect phylogenetic divergence in the proportion of embryogenesis completed before versus after laying. PMID:22174948

Heart Rate Monitor for Portable MP3 Player.

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Kim, Jaywoo; Lee, Mi-Hee; Lee, Hyoung-Ki; Choi, Kiwan; Bang, Seokwon; Kim, Sangryong

2005-01-01

This paper presents a photoplethysmography sensor based on a heart rate monitor for a portable MP3 player. Two major design issues are addressed: one is to acquire the sensor signal with a proper amplitude despite a wide range of variation and the other is to handle the noise contaminated signal which is caused by a motion artifact. A benchmarking test with a professional medical photoplethysmography sensor shows that our device performs very well in calculating heart rate even though our photoplethysmography sensor module was designed to be cost effective.

Poincaré plot analysis of ultra-short-term heart rate variability during recovery from exercise in physically active men.

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Gomes, Rayana L; Marques Vanderlei, Luiz C; Garner, David M; Ramos Santana, Milana D; de Abreu, Luiz C; Valenti, Vitor E

2017-04-26

Recently there has been increasing interest in the study of ultra-short- term heart rate variability (HRV) in sports performance and exercise physiology. In order to improve standardization of this specific analysis, we evaluated the ultra-short-term HRV analysis through SD1Poincaré index to identify exercise induced responses. We investigated 35 physically active men aged between 18 and 35 years old. Volunteers performed physical exercise on treadmill with intensity of 6.0 km / hour + 1% slope in the first five minutes for physical "warming up." This was followed by 25 minutes with intensity equivalent to 60% of Vmax, with the same slope according to the Conconi threshold. HRV was analyzed in the following periods: the five-minute period before the exercise and the five-minute period immediately after the exercise, the five minutes were divided into five segments of 60 RR intervals. Ultra-short-term RMSSD and SD1 analysis were performed. Ultra-short-term RMSSD and SD1 were significantly (panalysis with the Poincaré plot detected changes in HRV after exercise. Ultra-short-term HRV analysis through Poincaré plot identified heart rate autonomic responses induced by aerobic exercise.

Approximate entropy and point correlation dimension of heart rate variability in healthy subjects

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Storella, R J; Wood, H W; Mills, K M

1999-01-01

The contribution of nonlinear dynamics to heart rate variability in healthy humans was examined using surrogate data analysis. Several measures of heart rate variability were used and compared. Heart rates were recorded for three hours and original data sets of 8192 R-R intervals created. For each...... original data set (n = 34), three surrogate data sets were made by shuffling the order of the R-R intervals while retaining their linear correlations. The difference in heart rate variability between the original and surrogate data sets reflects the amount of nonlinear structure in the original data set....... Heart rate variability was analyzed by two different nonlinear methods, point correlation dimension and approximate entropy. Nonlinearity, though under 10 percent, could be detected with both types of heart rate variability measures. More importantly, not only were the correlations between...

Effects of omega-3 fatty acids on resting heart rate, heart rate recovery after exercise, and heart rate variability in men with healed myocardial infarctions and depressed ejection fractions.

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O'Keefe, James H; Abuissa, Hussam; Sastre, Antonio; Steinhaus, David M; Harris, William S

2006-04-15

We explored possible mechanisms by which recommended intakes of omega-3 fatty acids may decrease the risk for sudden cardiac death in patients with documented coronary heart disease. The cardioprotective effects of omega-3 fatty acids have been documented in epidemiologic and randomized controlled trials. These fatty acids are presumed to decrease susceptibility to fatal arrhythmias, but whether this is mediated by classic risk factors or direct cardiac mechanisms is not known. Eighteen white men with a history of myocardial infarction and ejection fractions <40% were randomized to placebo or omega-3 fatty acids (585 mg of docosahexaenoic acid and 225 mg of eicosapentaenoic acid) for two 4-month periods in a crossover design. At the end of each period, heart rate (HR), HR variability, and rate of HR recovery after exercise were determined, as were effects on arterial compliance, blood pressure, cardiac function, and fasting serum levels of lipids and inflammatory markers. Omega-3 fatty acids decreased HR at rest from 73 +/- 13 to 68 +/- 13 beats/min (p <0.0001) and improved 1-minute HR recovery after exercise (-27 +/- 10 to -32 +/- 12 beats/min, p <0.01). HR variability in the high-frequency band increased (p <0.02), but no change was noted in overall HR variability. There were no significant effects on blood pressure, arterial compliance, lipids, or inflammatory markers. These changes are consistent with an increase in vagal activity and may in part explain the observed decrease in risk for sudden cardiac death seen with omega-3 fatty acid supplementation.

Changes in heart rate variability and QT variability during the first trimester of pregnancy.

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Carpenter, R E; D'Silva, L A; Emery, S J; Uzun, O; Rassi, D; Lewis, M J

2015-03-01

The risk of new-onset arrhythmia during pregnancy is high, presumably relating to changes in both haemodynamic and cardiac autonomic function. The ability to non-invasively assess an individual's risk of developing arrhythmia during pregnancy would therefore be clinically significant. We aimed to quantify electrocardiographic temporal characteristics during the first trimester of pregnancy and to compare these with non-pregnant controls. Ninety-nine pregnant women and sixty-three non-pregnant women underwent non-invasive cardiovascular and haemodynamic assessment during a protocol consisting of various physiological states (postural manoeurvres, light exercise and metronomic breathing). Variables measured included stroke volume, cardiac output, heart rate, heart rate variability, QT and QT variability and QTVI (a measure of the variability of QT relative to that of RR). Heart rate (p pregnancy only during the supine position (p pregnancy in all physiological states (p pregnancy in all states (p pregnancy is associated with substantial changes in heart rate variability, reflecting a reduction in parasympathetic tone and an increase in sympathetic activity. QTVI shifted to a less favourable value, reflecting a greater than normal amount of QT variability. QTVI appears to be a useful method for quantifying changes in QT variability relative to RR (or heart rate) variability, being sensitive not only to physiological state but also to gestational age. We support the use of non-invasive markers of cardiac electrical variability to evaluate the risk of arrhythmic events in pregnancy, and we recommend the use of multiple physiological states during the assessment protocol.

iHeartLift: a closed loop system with bio-feedback that uses music tempo variability to improve heart rate variability.

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Ho, Thomas C T; Chen, Xiang

2011-01-01

"Musica delenit bestiam feram" translates into "Music soothes the savage beast". There is a hidden truth in this ancient quip passed down from generations. Besides soothing the heart, it also incites the heart to a healthier level of heart rate variability (HRV). In this paper, an approach to use and test music and biofeedback to increase the heart rate variability for people facing daily stress is discussed. By determining the music tempo variability (MTV) of a piece of music and current heart rate variability, iHeartLift is able to compare the 2 trends and locate a musical piece that is suited to increase the user's heart rate variability to a healthier level. With biofeedback, the 2 trends are continuously compared in real-time and the musical piece is changed in accordance with the current comparisons. A study was conducted and it was generally found that HRV can be uplifted by music regardless of language and meaning of musical lyrics but with limitations to musical genre.

Heart rate variability and baroreflex sensitivity in bilateral lung transplant recipients.

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Fontolliet, Timothée; Gianella, Pietro; Pichot, Vincent; Barthélémy, Jean-Claude; Gasche-Soccal, Paola; Ferretti, Guido; Lador, Frédéric

2018-01-09

The effects of lung afferents denervation on cardiovascular regulation can be assessed on bilateral lung transplantation patients. The high-frequency component of heart rate variability is known to be synchronous with breathing frequency. Then, if heart beat is neurally modulated by breathing frequency, we may expect disappearance of high frequency of heart rate variability in bilateral lung transplantation patients. On 11 patients and 11 matching healthy controls, we measured R-R interval (electrocardiography), blood pressure (Portapres ® ) and breathing frequency (ultrasonic device) in supine rest, during 10-min free breathing, 10-min cadenced breathing (0·25 Hz) and 5-min handgrip. We analysed heart rate variability and spontaneous variability of arterial blood pressure, by power spectral analysis, and baroreflex sensitivity, by the sequence method. Concerning heart rate variability, with respect to controls, transplant recipients had lower total power and lower low- and high-frequency power. The low-frequency/high-frequency ratio was higher. Concerning systolic, diastolic and mean arterial pressure variability, transplant recipients had lower total power (only for cadenced breathing), low frequency and low-frequency/high-frequency ratio during free and cadenced breathing. Baroreflex sensitivity was decreased. Denervated lungs induced strong heart rate variability reduction. The higher low-frequency/high-frequency ratio suggested that the total power drop was mostly due to high frequency. These results support the hypothesis that neural modulation from lung afferents contributes to the high frequency of heart rate variability. © 2018 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Control of the heart rate of rat embryos during the organogenic period

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Ritchie HE

2016-11-01

Full Text Available Helen E Ritchie,1 Carolina Ragnerstam,2 Elin Gustafsson,2 Johanna M Jonsson,2 William S Webster2 1Discipline of Biomedical Science, Sydney Medical School, University of Sydney, Lidcombe, 2Department of Anatomy and Histology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia Abstract: The aim of this study was to gain insight into whether the first trimester embryo could control its own heart rate (HR in response to hypoxia. The gestational day 13 rat embryo is a good model for the human embryo at 5–6 weeks gestation, as the heart is comparable in development and, like the human embryo, has no functional autonomic nerve supply at this stage. Utilizing a whole-embryo culture technique, we examined the effects of different pharmacological agents on HR under normoxic (95% oxygen and hypoxic (20% oxygen conditions. Oxygen concentrations ≤60% caused a concentration-dependent decrease in HR from normal levels of ~210 bpm. An adenosine agonist, AMP-activated protein kinase (AMPK activator and KATP channel opener all caused bradycardia in normoxic conditions; however, putative antagonists for these systems failed to prevent or ameliorate hypoxia-induced bradycardia. This suggests that the activation of one or more of these systems is not the primary cause of the observed hypoxia-induced bradycardia. Inhibition of oxidative phosphorylation also decreased HR in normoxic conditions, highlighting the importance of ATP levels. The β-blocker metoprolol caused a concentration-dependent reduction in HR supporting reports that β1-adrenergic receptors are present in the early rat embryonic heart. The cAMP inducer colforsin induced a positive chronotropic effect in both normoxic and hypoxic conditions. Overall, the embryonic HR at this stage of development is responsive to the level of oxygenation, probably as a consequence of its influence on ATP production. Keywords: embryonic heart rate, embryo, bradycardia, in vitro, ATP, hypoxia

Elevated resting heart rate, physical fitness and all-cause mortality

DEFF Research Database (Denmark)

Jensen, Magnus Thorsten; Suadicani, Poul; Hein, Hans Ole

2013-01-01

To examine whether elevated resting heart rate (RHR) is an independent risk factor for mortality or a mere marker of physical fitness (VO2Max).......To examine whether elevated resting heart rate (RHR) is an independent risk factor for mortality or a mere marker of physical fitness (VO2Max)....

An original piecewise model for computing energy expenditure from accelerometer and heart rate signals.

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Romero-Ugalde, Hector M; Garnotel, M; Doron, M; Jallon, P; Charpentier, G; Franc, S; Huneker, E; Simon, C; Bonnet, S

2017-07-28

Activity energy expenditure (EE) plays an important role in healthcare, therefore, accurate EE measures are required. Currently available reference EE acquisition methods, such as doubly labeled water and indirect calorimetry, are complex, expensive, uncomfortable, and/or difficult to apply on real time. To overcome these drawbacks, the goal of this paper is to propose a model for computing EE in real time (minute-by-minute) from heart rate and accelerometer signals. The proposed model, which consists of an original branched model, uses heart rate signals for computing EE on moderate to vigorous physical activities and a linear combination of heart rate and counts per minute for computing EE on light to moderate physical activities. Model parameters were estimated from a given data set composed of 53 subjects performing 25 different physical activities (light-, moderate- and vigorous-intensity), and validated using leave-one-subject-out. A different database (semi-controlled in-city circuit), was used in order to validate the versatility of the proposed model. Comparisons are done versus linear and nonlinear models, which are also used for computing EE from accelerometer and/or HR signals. The proposed piecewise model leads to more accurate EE estimations ([Formula: see text], [Formula: see text] and [Formula: see text] J kg -1 min -1 and [Formula: see text], [Formula: see text], and [Formula: see text] J kg -1 min -1 on each validation database). This original approach, which is more conformable and less expensive than the reference methods, allows accurate EE estimations, in real time (minute-by-minute), during a large variety of physical activities. Therefore, this model may be used on applications such as computing the time that a given subject spent on light-intensity physical activities and on moderate to vigorous physical activities (binary classification accuracy of 0.8155).

Evaluation of Stress Parameters Based on Heart Rate Variability Measurements

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Uysal, Fatma; Tokmakçı, Mahmut

2018-01-01

In this study, heart rate variabilitymeasurements and analysis was carried with help of the ECG recordings to showhow autonom nervous system activity changes. So as to evaluate the parametersrelated to stress of the study, the situation of relaxation, Stroop color/wordtest, mental test and auditory stimulus that would stress someone out wereapplied to six volunteer participants in a laboratory environment. Being takentotally seven minutes ECG recording and made analysis in time and frequencyd...

Target Heart Rates

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... Check Recipe Certification Program Nutrition Requirements Heart-Check Professional Resources Contact the Heart-Check Certification Program Simple Cooking and Recipes Dining Out Choosing a Restaurant Deciphering ...

Poincare indices for analyzing meditative heart rate signals

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Atefeh Goshvarpour

2015-06-01

Full Text Available Background: Poincare plots are commonly used to study the nonlinear behavior of physiologic signals. The aim of this study is to evaluate the Poincare plot indices of human heart rate signals during meditation. Methods: For this purpose, heart rate time series of eight Chi meditators available in Physionet database were used. Poincare plots with lags of 1 and 6 were constructed, and the ratio of the minor axis to major axis (SD1/SD2 and the area of Poincare plots were calculated for each lag. Results: The results show that the SD1/SD2 ratio increased significantly during meditation compared to that before meditation, especially the index measured from Poincare plots reconstructed with a lag of 6 (p < 0.05. In addition, in both lags, the area of Poincare plots decreased significantly during meditation compared to before meditation (p < 0.05. Conclusion: The comparative dynamic measures of the Poincare plot indices during and before meditation give more insight of the heart rate signals in a specific psychophysiological state.

Job strain and resting heart rate: a cross-sectional study in a Swedish random working sample

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Peter Eriksson

2016-03-01

Full Text Available Abstract Background Numerous studies have reported an association between stressing work conditions and cardiovascular disease. However, more evidence is needed, and the etiological mechanisms are unknown. Elevated resting heart rate has emerged as a possible risk factor for cardiovascular disease, but little is known about the relation to work-related stress. This study therefore investigated the association between job strain, job control, and job demands and resting heart rate. Methods We conducted a cross-sectional survey of randomly selected men and women in Västra Götalandsregionen, Sweden (West county of Sweden (n = 1552. Information about job strain, job demands, job control, heart rate and covariates was collected during the period 2001–2004 as part of the INTERGENE/ADONIX research project. Six different linear regression models were used with adjustments for gender, age, BMI, smoking, education, and physical activity in the fully adjusted model. Job strain was operationalized as the log-transformed ratio of job demands over job control in the statistical analyses. Results No associations were seen between resting heart rate and job demands. Job strain was associated with elevated resting heart rate in the unadjusted model (linear regression coefficient 1.26, 95 % CI 0.14 to 2.38, but not in any of the extended models. Low job control was associated with elevated resting heart rate after adjustments for gender, age, BMI, and smoking (linear regression coefficient −0.18, 95 % CI −0.30 to −0.02. However, there were no significant associations in the fully adjusted model. Conclusions Low job control and job strain, but not job demands, were associated with elevated resting heart rate. However, the observed associations were modest and may be explained by confounding effects.

Heart rate detection from an electronic weighing scale

International Nuclear Information System (INIS)

González-Landaeta, R; Casas, O; Pallàs-Areny, R

2008-01-01

We propose a novel technique for beat-to-beat heart rate detection based on the ballistocardiographic (BCG) force signal from a subject standing on a common electronic weighing scale. The detection relies on sensing force variations related to the blood acceleration in the aorta, works even if wearing footwear and does not require any sensors attached to the body because it uses the load cells in the scale. We have devised an approach to estimate the sensitivity and frequency response of three commercial weighing scales to assess their capability to detect the BCG force signal. Static sensitivities ranged from 490 nV V −1 N −1 to 1670 nV V −1 N −1 . The frequency response depended on the subject's mass but it was broad enough for heart rate estimation. We have designed an electronic pulse detection system based on off-the-shelf integrated circuits to sense heart-beat-related force variations of about 0.24 N. The signal-to-noise ratio of the main peaks of the force signal detected was higher than 30 dB. A Bland–Altman plot was used to compare the RR time intervals estimated from the ECG and BCG force signals for 17 volunteers. The error was ±21 ms, which makes the proposed technique suitable for short-term monitoring of the heart rate

Separating the effect of respiration from the heart rate variability for cases of constant harmonic breathing

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Kircher Michael

2015-09-01

Full Text Available Heart Rate Variability studies are a known measure for the autonomous control of the heart rate. In special situations, its interpretation can be ambiguous, since the respiration has a major influence on the heart rate variability. For this reason it has often been proposed to measure Heart Rate Variability, while the subjects are breathing at a constant respiration rate. That way the spectral influence of the respiration is known. In this work we propose to remove this constant respiratory influence from the heart rate and the Heart Rate Variability parameters to gain respiration free autonomous controlled heart rate signal. The spectral respiratory component in the heart rate signal is detected and characterized. Subsequently the respiratory effect on Heart Rate Variability is removed using spectral filtering approaches, such as the Notch filter or the Raised Cosine filter. As a result new decoupled Heart Variability parameters are gained, which could lead to new additional interpretations of the autonomous control of the heart rate.

Functionality of the baroreceptor nerves in heart rate regulation

DEFF Research Database (Denmark)

Ottesen, Johnny T.; Olufsen, Mette

2011-01-01

are a consequence of the memory encapsulated by the models, and the nonlinearity gives rise to sigmoidal response curves. The nonlinear afferent baroreceptor models are coupled with an effector model, and the coupled model has been used to predict baroreceptor feedback regulation of heart rate during postural...... change from sitting to standing and during head-up tilt. The efferent model couples the afferent nerve paths to the sympathetic and parasympathetic outflow, and subsequently predicts the build up of an action potential at the sinus knot of the heart. In this paper, we analyze the nonlinear afferent model...... and show that the coupled model is able to predict heart rate regulation using blood pressure data as an input...

New descriptors of T-wave morphology are independent of heart rate

DEFF Research Database (Denmark)

Andersen, Mads Peter; Xue, Joel Q; Graff, Claus

2008-01-01

from daytime Holter recordings. Duration parameters (QT, ToTe, TpTe, and others), a number of basic T-wave morphology parameters (amplitude, area, and others) as well as advanced morphology descriptors (asymmetry, flatness, and others) were measured automatically. Heart rate dependence was examined...... by means of analysis of covariance. The results showed clear heart rate dependence for the QT interval (R(2) = 0.53-0.57) and a moderate degree of heart rate dependence for the basic morphology parameters (amplitude, area, and others) (R(2) = 0.17-0.42). Both the advanced T-wave descriptors (asymmetry......T-wave morphology descriptors are sensitive to drug-induced changes and may be a useful addition to the QT interval in cardiac safety trials. Intrasubject heart rate dependence of T-wave morphology was investigated in a sample of 39 healthy individuals. Ten-second electrocardiograms were obtained...

Unconstrained monitoring of long-term heart and breath rates during sleep

International Nuclear Information System (INIS)

Chen, Wenxi; Zhu, Xin; Wei, Daming; Nemoto, Tetsu; Sugitani, Kayo; Kitamura, Kei-ichiro

2008-01-01

An unconstrained method for the long-term monitoring of heart and breath rates during sleep is proposed. The system includes a sensor unit and a web-based network module. The sensor unit is set beneath a pillow to pick up the pressure variations from the head induced by inhalation/exhalation movements and heart pulsation during sleep. The measured pressure signal was digitized and transferred to a remote database server via the network module. A wavelet-based algorithm was employed to detect the heart and breath rates, as well as body movement, during sleep. The overall system was utilized for a total six-month trial operation delivered to a female subject. The profiles of the heart and breath rates on a beat-by-beat and daily basis were obtained. Movements during sleep were also estimated. The results show that the daily average percentage of undetectable periods (UPs) during 881.6 sleep hours over a 180 day period was 17.2%. A total of 89.2% of sleep hours had a UP of not more than 25%. The profile of the heart rate revealed a periodic property that corresponded to the female monthly menstrual cycle. Our system shows promise as a long-term unconstrained monitor for heart and breath rates, and for other physiological parameters related to the quality of sleep and the regularity of the menstrual cycle. (note)

Examining the Relationship between Heart Rate and Problem Behavior: A Case Study of Severe Skin Picking in Prader-Willi Syndrome

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Hall, Scott S.; Hammond, Jennifer L.; Hustyi, Kristin M.

2013-01-01

Few studies have examined the relationship between heart rate and self-injurious behavior (SIB) shown by individuals with IDD (intellectual and developmental disabilities). In this single-case study, we simultaneously monitored heart rate and activity levels during a functional analysis of severe skin picking behavior exhibited by a young man with…

Selective attenuation of norepinephrine release and stress-induced heart rate increase by partial adenosine A1 agonism.

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Lorenz Bott-Flügel

Full Text Available The release of the neurotransmitter norepinephrine (NE is modulated by presynaptic adenosine receptors. In the present study we investigated the effect of a partial activation of this feedback mechanism. We hypothesized that partial agonism would have differential effects on NE release in isolated hearts as well as on heart rate in vivo depending on the genetic background and baseline sympathetic activity. In isolated perfused hearts of Wistar and Spontaneously Hypertensive Rats (SHR, NE release was induced by electrical stimulation under control conditions (S1, and with capadenoson 6 · 10(-8 M (30 µg/l, 6 · 10(-7 M (300 µg/l or 2-chloro-N(6-cyclopentyladenosine (CCPA 10(-6 M (S2. Under control conditions (S1, NE release was significantly higher in SHR hearts compared to Wistar (766+/-87 pmol/g vs. 173+/-18 pmol/g, p<0.01. Capadenoson led to a concentration-dependent decrease of the stimulation-induced NE release in SHR (S2/S1  =  0.90 ± 0.08 with capadenoson 6 · 10(-8 M, 0.54 ± 0.02 with 6 · 10(-7 M, but not in Wistar hearts (S2/S1  =  1.05 ± 0.12 with 6 · 10(-8 M, 1.03 ± 0.09 with 6 · 10(-7 M. CCPA reduced NE release to a similar degree in hearts from both strains. In vivo capadenoson did not alter resting heart rate in Wistar rats or SHR. Restraint stress induced a significantly greater increase of heart rate in SHR than in Wistar rats. Capadenoson blunted this stress-induced tachycardia by 45% in SHR, but not in Wistar rats. Using a [(35S]GTPγS assay we demonstrated that capadenoson is a partial agonist compared to the full agonist CCPA (74+/-2% A(1-receptor stimulation. These results suggest that partial adenosine A(1-agonism dampens stress-induced tachycardia selectively in rats susceptible to strong increases in sympathetic activity, most likely due to a presynaptic attenuation of NE release.

Aggressive behavior: an alternative model of resting heart rate and sensation seeking.

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Wilson, Laura C; Scarpa, Angela

2014-01-01

Low resting heart rate is a well-replicated biological correlate of aggression, and sensation seeking is frequently cited as the underlying causal explanation. However, little empirical evidence supports this mediating relationship. Furthermore, the biosocial model of violence and social push theory suggest sensation seeking may moderate the relationship between heart rate and aggression. In a sample of 128 college students (82.0% White; 73.4% female), the current study tested a moderation model as an alternative relationship between resting heart rate and sensation seeking in regard to aggression. Overall, the findings partially supported an interaction effect, whereby the relationship between heart rate and aggression was moderated by sensation seeking. Specifically, the oft-noted relationship between low resting heart rate and increased aggression was found, but only for individuals with low levels of sensation seeking. If replication supports this finding, the results may better inform prevention and intervention work. © 2013 Wiley Periodicals, Inc.

Heart Rate and Increased Intravascular Volume

Czech Academy of Sciences Publication Activity Database

Souček, M.; Kára, T.; Jurák, Pavel; Halámek, Josef; Špinarová, L.; Meluzín, J.; Toman, J.; Řiháček, I.; Šumbera, J.; Fráňa, P.

2003-01-01

Roč. 52, - (2003), s. 137 - 140 ISSN 0862-8408 R&D Projects: GA ČR GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : kidneys * heart rate * atrial mechanisms Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 0.939, year: 2003

Long-Term Persistency of Abnormal Heart Rate Variability following Long NICU Stay and Surgery at Birth

Directory of Open Access Journals (Sweden)

Mélanie Morin

2014-01-01

Full Text Available Preterm birth is associated with painful procedures during the neonatal intensive care unit (NICU stay. Full-term newborns can also experience pain, following surgery. These procedures can have long-lasting consequences. It has been shown that children born preterm show pain responses and cardiac alterations. This study aimed to explore the heart rate reactivity to pain in 107 subjects born either preterm or full-term who were between 7 and 25 years old at testing. We also evaluated the effect of pain experienced at birth, as represented by a longer NICU stay, time under ventilation, and surgery at birth. Participants were asked to immerse their right forearm in 10°C water for 2 minutes. Electrocardiograms were recorded at baseline and during the immersion procedure. Full-term subjects showed a stable increase in heart rate throughout the procedure, whereas preterm ones showed a strong increase at the beginning, which decreased over time. Also, preterm and full-term subjects who experienced pain at birth showed higher resting heart rate, stronger sympathetic activity, and lower cardiac vagal activity. Our study demonstrated a long-term impact of a long NICU stay and surgery at birth on cardiac autonomic activity. This could lead to impaired reactions to pain or stress in later life.

Triboelectric Nanogenerator Enabled Body Sensor Network for Self-Powered Human Heart-Rate Monitoring.

Science.gov (United States)

Lin, Zhiming; Chen, Jun; Li, Xiaoshi; Zhou, Zhihao; Meng, Keyu; Wei, Wei; Yang, Jin; Wang, Zhong Lin

2017-09-26

Heart-rate monitoring plays a critical role in personal healthcare management. A low-cost, noninvasive, and user-friendly heart-rate monitoring system is highly desirable. Here, a self-powered wireless body sensor network (BSN) system is developed for heart-rate monitoring via integration of a downy-structure-based triboelectric nanogenerator (D-TENG), a power management circuit, a heart-rate sensor, a signal processing unit, and Bluetooth module for wireless data transmission. By converting the inertia energy of human walking into electric power, a maximum power of 2.28 mW with total conversion efficiency of 57.9% was delivered at low operation frequency, which is capable of immediately and sustainably driving the highly integrated BSN system. The acquired heart-rate signal by the sensor would be processed in the signal process circuit, sent to an external device via the Bluetooth module, and displayed on a personal cell phone in a real-time manner. Moreover, by combining a TENG-based generator and a TENG-based sensor, an all-TENG-based wireless BSN system was developed, realizing continuous and self-powered heart-rate monitoring. This work presents a potential method for personal heart-rate monitoring, featured as being self-powered, cost-effective, noninvasive, and user-friendly.

Relationships between heart rate and age, bodyweight and breed in 10,849 dogs.

Science.gov (United States)

Hezzell, M J; Dennis, S G; Humm, K; Agee, L; Boswood, A

2013-06-01

To evaluate relationships between heart rate and clinical variables in healthy dogs and dogs examined at a referral hospital. Clinical data were extracted from the electronic patient records of a first opinion group (5000 healthy dogs) and a referral hospital (5849 dogs). Univariable and multi-variable general linear models were used to assess associations between heart rate and clinical characteristics. Separate multi-variable models were constructed for first opinion and referral populations. In healthy dogs, heart rate was negatively associated with bodyweight (PChihuahuas. The mean difference in heart rate between a 5 and 55 kg dog was 10.5 beats per minute. In dogs presenting to a referral hospital, heart rate was negatively associated with bodyweight (P<0.001) and the following breeds; border collie, golden retriever, Labrador retriever, springer spaniel and West Highland white terrier and positively associated with age, admitting service (emergency and critical care, emergency first opinion and cardiology) and the following breeds; Cavalier King Charles spaniel, Staffordshire bull terrier and Yorkshire terrier. Bodyweight, age, breed and disease status all influence heart rate in dogs, although these factors account for a relatively small proportion of the overall variability in heart rate. © 2013 British Small Animal Veterinary Association.

Assessing positive emotional states in dogs using heart rate and heart rate variability.

Science.gov (United States)

Zupan, Manja; Buskas, Julia; Altimiras, Jordi; Keeling, Linda J

2016-03-01

Since most animal species have been recognized as sentient beings, emotional state may be a good indicator of welfare in animals. The goal of this study was to manipulate the environment of nine beagle research dogs to highlight physiological responses indicative of different emotional experiences. Stimuli were selected to be a more or a less positive food (meatball or food pellet) or social reward (familiar person or less familiar person). That all the stimuli were positive and of different reward value was confirmed in a runway motivation test. Dogs were tested individually while standing facing a display theatre where the different stimuli could be shown by lifting a shutter. The dogs approached and remained voluntarily in the test system. They were tested in four sessions (of 20s each) for each of the four stimuli. A test session consisted of four presentation phases (1st exposure to stimulus, post exposure, 2nd exposure, and access to reward). Heart rate (HR) and heart rate variability (HRV) responses were recorded during testing in the experimental room and also when lying resting in a quiet familiar room. A new method of 'stitching' short periods of HRV data together was used in the analysis. When testing different stimuli, no significant differences were observed in HR and LF:HF ratio (relative power in low frequency (LF) and the high-frequency (HF) range), implying that the sympathetic tone was activated similarly for all the stimuli and may suggest that dogs were in a state of positive arousal. A decrease of HF was associated with the meatball stimulus compared to the food pellet and the reward phase (interacting with the person or eating the food) was associated with a decrease in HF and RMSSD (root mean square of successive differences of inter-beat intervals) compared to the preceding phase (looking at the person or food). This suggests that parasympathetic deactivation is associated with a more positive emotional state in the dog. A similar reduction

Muscle metaboreflex and autonomic regulation of heart rate in humans

DEFF Research Database (Denmark)

Fisher, James P; Adlan, Ahmed M; Shantsila, Alena

2013-01-01

) conditions, but attenuated with β-adrenergic blockade (0.2 ± 1 beats min(-1); P > 0.05 vs. rest). Thus muscle metaboreflex activation-mediated increases in HR are principally attributable to increased cardiac sympathetic activity, and only following exercise with a large muscle mass (PEI following leg......We elucidated the autonomic mechanisms whereby heart rate (HR) is regulated by the muscle metaboreflex. Eight male participants (22 ± 3 years) performed three exercise protocols: (1) enhanced metaboreflex activation with partial flow restriction (bi-lateral thigh cuff inflation) during leg cycling...... exercise, (2) isolated muscle metaboreflex activation (post-exercise ischaemia; PEI) following leg cycling exercise, (3) isometric handgrip followed by PEI. Trials were undertaken under control (no drug), β1-adrenergic blockade (metoprolol) and parasympathetic blockade (glycopyrrolate) conditions. HR...

Healthy hearts--and the universal benefits of being physically active: physical activity and health.

Science.gov (United States)

Blair, Steven N; Morris, Jeremy N

2009-04-01

Although ancient thinkers suggested that physical activity is good for health, systematic research on the topic did not begin until the middle of the 20th century. Early reports showed that individuals in active occupations had lower rates of heart disease than individuals in sedentary occupations. Investigators then began to evaluate leisure-time physical activity and health and found similar results. Later research used objective measures of cardiorespiratory fitness as the exposure, and found even stronger associations with health outcomes. Recent research has extended the earlier findings on activity or fitness and heart disease to a wide variety of health outcomes. We now know that regular physical activity of 150 minutes/week of moderate intensity physical activity reduces the risk of numerous chronic diseases, preserves health and function (both physical and mental) into old age, and extends longevity. The current challenge is to develop programs and interventions to promote physical activity for all in our increasingly sedentary societies.

Heart rate effects of intraosseous injections using slow and fast rates of anesthetic solution deposition.

Science.gov (United States)

Susi, Louis; Reader, Al; Nusstein, John; Beck, Mike; Weaver, Joel; Drum, Melissa

2008-01-01

The authors, using a crossover design, randomly administered, in a single-blind manner, 3 primary intraosseous injections to 61 subjects using: the Wand local anesthetic system at a deposition rate of 45 seconds (fast injection); the Wand local anesthetic system at a deposition rate of 4 minutes and 45 seconds (slow injection); a conventional syringe injection at a deposition rate of 4 minutes and 45 seconds (slow injection), in 3 separate appointments spaced at least 3 weeks apart. A pulse oximeter measured heart rate (pulse). The results demonstrated the mean maximum heart rate was statistically higher with the fast intraosseous injection (average 21 to 28 beats/min increase) than either of the 2 slow intraosseous injections (average 10 to 12 beats/min increase). There was no statistically significant difference between the 2 slow injections. We concluded that an intraosseous injection of 1.4 mL of 2% lidocaine with 1 : 100,000 epinephrine with the Wand at a 45-second rate of anesthetic deposition resulted in a significantly higher heart rate when compared with a 4-minute and 45-second anesthetic solution deposition using either the Wand or traditional syringe.

Value of Serial Heart Rate Variability Measurement for Prediction of Appropriate ICD Discharge in Patients with Heart Failure

NARCIS (Netherlands)

ten Sande, Judith N.; Damman, Peter; Tijssen, Jan G. P.; de Groot, Joris R.; Knops, Reinoud E.; Wilde, Arthur A. M.; van Dessel, Pascal F. H. M.

2014-01-01

HRV and Appropriate ICD Shock in Heart Failure Introduction Decreased heart rate variability (HRV) is associated with adverse outcomes in patients with heart failure. Our objective was to examine whether decreased HRV predicts appropriate implantable cardioverter defibrillator (ICD) shocks. Methods

Smart pillow for heart-rate monitoring using a fiber optic sensor

Science.gov (United States)

Chen, Zhihao; Teo, Ju Teng; Ng, Soon Huat; Yim, Huiqing

2011-03-01

In this paper, we propose and demonstrate a new method to monitor heart rate using fiber optic microbending based sensor for in-bed non-intrusive monitoring. The sensing system consists of transmitter, receiver, sensor mat, National Instrument (NI) data acquisition (DAQ) card and a computer for signal processing. The sensor mat is embedded inside a commercial pillow. The heart rate measurement system shows an accuracy of +/-2 beats, which has been successfully demonstrated in a field trial. The key technological advantage of our system is its ability to measure heart rate with no preparation and minimal compliance by the patient.

Heart rate responses provide an objective evaluation of human disturbance stimuli in breeding birds.

Science.gov (United States)

Ellenberg, Ursula; Mattern, Thomas; Seddon, Philip J

2013-01-01

Intuition is a poor guide for evaluating the effects of human disturbance on wildlife. Using the endangered Yellow-eyed penguin, Megadyptes antipodes, as an example, we show that heart rate responses provide an objective tool to evaluate human disturbance stimuli and encourage the wider use of this simple and low-impact approach. Yellow-eyed penguins are a flagship species for New Zealand's wildlife tourism; however, unregulated visitor access has recently been associated with reduced breeding success and lower first year survival. We measured heart rate responses of Yellow-eyed penguins via artificial eggs to evaluate a range of human stimuli regularly occurring at their breeding sites. We found the duration of a stimulus to be the most important factor, with elevated heart rate being sustained while a person remained within sight. Human activity was the next important component; a simulated wildlife photographer, crawling slowly around during his stay, elicited a significantly higher heart rate response than an entirely motionless human spending the same time at the same distance. Stimuli we subjectively might perceive as low impact, such as the careful approach of a 'wildlife photographer', resulted in a stronger response than a routine nest-check that involved lifting a bird up to view nest contents. A single, slow-moving human spending 20 min within 2 m from the nest may provoke a response comparable to that of 10 min handling a bird for logger deployment. To reduce cumulative impact of disturbance, any human presence in the proximity of Yellow-eyed penguins needs to be kept at a minimum. Our results highlight the need for objective quantification of the effects of human disturbance in order to provide a sound basis for guidelines to manage human activity around breeding birds.

Promising effects of xanthine oxidase inhibition by allopurinol on autonomic heart regulation estimated by heart rate variability (HRV) analysis in rats exposed to hypoxia and hyperoxia

Science.gov (United States)

Ziółkowski, Wiesław; Badtke, Piotr; Zajączkowski, Miłosz A.; Flis, Damian J.; Figarski, Adam; Smolińska-Bylańska, Maria; Wierzba, Tomasz H.

2018-01-01

Background It has long been suggested that reactive oxygen species (ROS) play a role in oxygen sensing via peripheral chemoreceptors, which would imply their involvement in chemoreflex activation and autonomic regulation of heart rate. We hypothesize that antioxidant affect neurogenic cardiovascular regulation through activation of chemoreflex which results in increased control of sympathetic mechanism regulating heart rhythm. Activity of xanthine oxidase (XO), which is among the major endogenous sources of ROS in the rat has been shown to increase during hypoxia promote oxidative stress. However, the mechanism of how XO inhibition affects neurogenic regulation of heart rhythm is still unclear. Aim The study aimed to evaluate effects of allopurinol-driven inhibition of XO on autonomic heart regulation in rats exposed to hypoxia followed by hyperoxia, using heart rate variability (HRV) analysis. Material and methods 16 conscious male Wistar rats (350 g): control-untreated (N = 8) and pretreated with Allopurinol-XO inhibitor (5 mg/kg, followed by 50 mg/kg), administered intraperitoneally (N = 8), were exposed to controlled hypobaric hypoxia (1h) in order to activate chemoreflex. The treatment was followed by 1h hyperoxia (chemoreflex suppression). Time-series of 1024 RR-intervals were extracted from 4kHz ECG recording for heart rate variability (HRV) analysis in order to calculate the following time-domain parameters: mean RR interval (RRi), SDNN (standard deviation of all normal NN intervals), rMSSD (square root of the mean of the squares of differences between adjacent NN intervals), frequency-domain parameters (FFT method): TSP (total spectral power) as well as low and high frequency band powers (LF and HF). At the end of experiment we used rat plasma to evaluate enzymatic activity of XO and markers of oxidative stress: protein carbonyl group and 8-isoprostane concentrations. Enzymatic activity of superoxide dismutase (SOD), catalase (CAT) and glutathione

Promising effects of xanthine oxidase inhibition by allopurinol on autonomic heart regulation estimated by heart rate variability (HRV analysis in rats exposed to hypoxia and hyperoxia.

Directory of Open Access Journals (Sweden)

Stanisław Zajączkowski

Full Text Available It has long been suggested that reactive oxygen species (ROS play a role in oxygen sensing via peripheral chemoreceptors, which would imply their involvement in chemoreflex activation and autonomic regulation of heart rate. We hypothesize that antioxidant affect neurogenic cardiovascular regulation through activation of chemoreflex which results in increased control of sympathetic mechanism regulating heart rhythm. Activity of xanthine oxidase (XO, which is among the major endogenous sources of ROS in the rat has been shown to increase during hypoxia promote oxidative stress. However, the mechanism of how XO inhibition affects neurogenic regulation of heart rhythm is still unclear.The study aimed to evaluate effects of allopurinol-driven inhibition of XO on autonomic heart regulation in rats exposed to hypoxia followed by hyperoxia, using heart rate variability (HRV analysis.16 conscious male Wistar rats (350 g: control-untreated (N = 8 and pretreated with Allopurinol-XO inhibitor (5 mg/kg, followed by 50 mg/kg, administered intraperitoneally (N = 8, were exposed to controlled hypobaric hypoxia (1h in order to activate chemoreflex. The treatment was followed by 1h hyperoxia (chemoreflex suppression. Time-series of 1024 RR-intervals were extracted from 4kHz ECG recording for heart rate variability (HRV analysis in order to calculate the following time-domain parameters: mean RR interval (RRi, SDNN (standard deviation of all normal NN intervals, rMSSD (square root of the mean of the squares of differences between adjacent NN intervals, frequency-domain parameters (FFT method: TSP (total spectral power as well as low and high frequency band powers (LF and HF. At the end of experiment we used rat plasma to evaluate enzymatic activity of XO and markers of oxidative stress: protein carbonyl group and 8-isoprostane concentrations. Enzymatic activity of superoxide dismutase (SOD, catalase (CAT and glutathione peroxidase (GPx were measures in erythrocyte

QT measurement and heart rate correction during hypoglycemia

DEFF Research Database (Denmark)

Christensen, Toke Folke; Randløv, Jette; Christensen, Leif Engmann

2010-01-01

induced by intravenous injection of two insulin types in a cross-over design. QT measurements were done using the slope-intersect (SI) and manual annotation (MA) methods. Heart rate correction was done using Bazett's (QTcB) and Fridericia's (QTcF) formulas. Results. The SI method showed significant......Introduction. Several studies show that hypoglycemia causes QT interval prolongation. The aim of this study was to investigate the effect of QT measurement methodology, heart rate correction, and insulin types during hypoglycemia. Methods. Ten adult subjects with type 1 diabetes had hypoglycemia...... prolongation at hypoglycemia for QTcB (42(6) ms; P measuring the QT interval has...

Age-related disappearance of Mayer-like heart rate waves

Science.gov (United States)

Jarisch, W. R.; Ferguson, J. J.; Shannon, R. P.; Wei, J. Y.; Goldberger, A. L.

1987-01-01

The effect of age on the principal spectral components of heart rate obtained immediately after passive upright tilt was investigated in human subjects who underwent a 60-deg tilt over 9 sec. Two groups were examined, the first of which consisting of healthy male subjects aged 22-26 years, while the second was comprised of subjects aged 65-84 years on no medication; radiograms were recorded continuously beginning just prior to tilt until 3 min posttilt. The results of spectral analysis showed that elderly subjects did not exhibit the Mayer-like heart rate waves (the 0.07-0.09 Hz oscillations) that were present in the spectra of young subjects immediately after passive upright tilt. The findings are consistent with the concept of a 'dysautonomia of aging'. It is suggested that postural stress testing with spectral analysis of heart rate fluctuations may provide a useful way of assessing physiologic vs chronologic age.

Estimating energy expenditure from heart rate in older adults: a case for calibration.

Science.gov (United States)

Schrack, Jennifer A; Zipunnikov, Vadim; Goldsmith, Jeff; Bandeen-Roche, Karen; Crainiceanu, Ciprian M; Ferrucci, Luigi

2014-01-01

Accurate measurement of free-living energy expenditure is vital to understanding changes in energy metabolism with aging. The efficacy of heart rate as a surrogate for energy expenditure is rooted in the assumption of a linear function between heart rate and energy expenditure, but its validity and reliability in older adults remains unclear. To assess the validity and reliability of the linear function between heart rate and energy expenditure in older adults using different levels of calibration. Heart rate and energy expenditure were assessed across five levels of exertion in 290 adults participating in the Baltimore Longitudinal Study of Aging. Correlation and random effects regression analyses assessed the linearity of the relationship between heart rate and energy expenditure and cross-validation models assessed predictive performance. Heart rate and energy expenditure were highly correlated (r=0.98) and linear regardless of age or sex. Intra-person variability was low but inter-person variability was high, with substantial heterogeneity of the random intercept (s.d. =0.372) despite similar slopes. Cross-validation models indicated individual calibration data substantially improves accuracy predictions of energy expenditure from heart rate, reducing the potential for considerable measurement bias. Although using five calibration measures provided the greatest reduction in the standard deviation of prediction errors (1.08 kcals/min), substantial improvement was also noted with two (0.75 kcals/min). These findings indicate standard regression equations may be used to make population-level inferences when estimating energy expenditure from heart rate in older adults but caution should be exercised when making inferences at the individual level without proper calibration.

Orbital bleeding in rats while under diethylether anaesthesia does not influence telemetrically determined heart rate, body temperature, locomotor and eating activity when compared with anaesthesia alone

NARCIS (Netherlands)

vanHerck, H; DeBoer, SF; Hesp, APM; VanLith, HA; Baumans, [No Value; Beynen, AC; Herck, H. van; Lith, H.A. van

The question addressed was whether orbital bleeding in rats, while under diethylether anaesthesia, affects their locomotor activity, body core temperature, heart rate rhythm and eating pattern. Roman High Avoidance (RHA) and Roman Low Avoidance (RLA) rats were used to enhance generalization of the

Resemblances of Parents and Twins in Sport Participation and Heart Rate

NARCIS (Netherlands)

Boomsma, D.I.; van den Bree, M.B.; Orlebeke, J.F.; Molenaar, P.C.M.

1989-01-01

A model to analyze resemblances of twins and parents using LISREL is outlined and applied to sports participation and heart-rate data. Sports participation and heart rate were measured in 44 monozygotic and 46 dizygotic adolescent twin pairs and in their parents. Genetic factors influence variation

Gaussian Mixture Model of Heart Rate Variability

Science.gov (United States)

Costa, Tommaso; Boccignone, Giuseppe; Ferraro, Mario

2012-01-01

Heart rate variability (HRV) is an important measure of sympathetic and parasympathetic functions of the autonomic nervous system and a key indicator of cardiovascular condition. This paper proposes a novel method to investigate HRV, namely by modelling it as a linear combination of Gaussians. Results show that three Gaussians are enough to describe the stationary statistics of heart variability and to provide a straightforward interpretation of the HRV power spectrum. Comparisons have been made also with synthetic data generated from different physiologically based models showing the plausibility of the Gaussian mixture parameters. PMID:22666386

Total Artificial Heart Implantation as a Bridge to Heart Transplantation in an Active Duty Service Member With Amyloid Cardiomyopathy.

Science.gov (United States)

Scully, Michael S; Wessman, Dylan E; McKee, James M; Francisco, Gregory M; Nayak, Keshav R; Kobashigawa, Jon A

2017-03-01

Cardiac involvement by light-chain (AL) amyloid occurs in up to 50% of patients with primary AL amyloidosis. The prognosis of amyloid heart disease is poor with 1-year survival rates of 35 to 40%. Historically, heart transplantation was considered controversial for patients with AL amyloid cardiomyopathy (CM) given the systemic nature of the disease and poor survival. We present a case report of an active duty service member diagnosed with advanced cardiac amyloid who underwent total artificial heart transplant as a bridge to heart transplant and eventual autologous stem cell transplant. A 47-year-old active duty male initially evaluated for atypical chest pain was found to have severe concentric left ventricular hypertrophy on echocardiogram but normal voltage on electrocardiogram. Cardiac magnetic resonance imaging, laboratory studies, and bone marrow biopsy established the diagnosis of cardiac amyloidosis. At the time of diagnosis, the patient's prognosis was very poor with a median survival of 5 months on the basis of the Mayo Clinic revised prognostic staging system for amyloidosis. The patient developed rapidly progressive left ventricular dysfunction and heart failure leading to cardiac arrest. The patient received a total artificial heart as a bridge to orthotopic heart and kidney transplantation and eventual stem cell transplant. He continues to be in remission and has a fair functional capacity without restriction in activities of daily living or moderate exercise. Amyloid CM is a rare and devastating disease. The natural course of the disease has made heart transplant in these patients controversial. Modern advancements in chemotherapies and advanced heart failure treatments have improved outcomes for select patients with AL amyloid CM undergoing heart transplantation. There is ongoing research seeking improvement in treatment options and outcomes for patients with this deadly disease. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

Adaptive Mean and Trend Removal of Heart Rate Variability Using Kalman Filtering

National Research Council Canada - National Science Library

Schloegl, A

2001-01-01

Analysis of heart rate van ability requires the calculation of the mean heart rate, Adaptive methods are important for online and real-time parameter estimation, In this paper we demonstrate the use...

The effect of programmed exercise on body compositions and heart rate of 11-13 years-old male students

Directory of Open Access Journals (Sweden)

Mohammad H. Dashti

2011-11-01

Full Text Available Background: Different forms of physical activities can play a very important role in improving health and physical fitness. The purpose of this study was to examine the effect of the programmed exercise on students’ body compositions and heart rate at rest.Materials and Method: Two groups each consisting of 15students, aged averagely 12.6 years were the subjects of this experimental study. The experimental group in each session took part in an exercise program consisting of 20 minutes of aerobic activity (running, 10 minutes of aerobic exercise, 30 minutes of local training and 5 minutes of free exercise. The experiment last for 24 sessions. Control group didn’t do any special practice. In both groups, weight, fat mass, fat percentage, lean body mass and heart rate were measured during rest period before and after the experiment. Results: Results showed that the fat percentage, weight, fat mass and heart rate had decreased after 8 weeks of programmed exercise in the experimental group unlike the control group. However, no significant difference was observed in lean body mass.Conclusion: The exercise program used in this study may help loosing weight and make the heart stronger

iHeartrate: a heart rate controlled in-flight music recommendation system

NARCIS (Netherlands)

Liu, H.; Hu, J.; Rauterberg, G.W.M.; Spink, A.J.; Grieco, O.E.; Krips, L.W.S.; Loijens, L.P.J.J.; Noldus, xx; Zimmerman, P.H.

2010-01-01

Travel by air, especially long distance, the enclosed environment of the aircraft cabin causes discomfort and even stress to flight passengers. In this paper, we present a new heart rate controlled music recommendation system. Heart rate is used as a stress indicator. If the user is stressed and

Positive correlation between blood pressure or heart rate and chymase-dependent angiotensin II-forming activity in circulating mononuclear leukocytes measured by new ELISA.

Science.gov (United States)

Okamura, Keisuke; Okuda, Tetsu; Shirai, Kazuyuki; Urata, Hidenori

2018-01-01

The aim of the present study was to establish a convenient clinically applicable assay method for chymase-dependent angiotensin II forming activity of circulating mononuclear leukocytes (CML), which was potentially a marker of tissue chymase activity. Using this method, association between CML chymase activity and clinical parameters was determined. Cardiovascular outpatients (n = 170) without taking antihypertensive medication were recruited. An ELISA for chymase-dependent angiotensin II-forming activity in CML was established using Nma /Dnp-modified angiotensin I. Logistic regression analysis revealed that age and male gender were significant independent determinants of the increased CML chymase activity. After adjustment by age and gender, the CML chymase activity was positively correlated with systolic blood pressure, pulse rate, and the brain natriuretic peptide level. The relation between blood pressure and CML chymase activity suggests that it might reflect that increased tissue chymase activity contributes to systemic high blood pressure and heart rate because plasma chymase is inactive due to inhibitory plasma inhibitors.

Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders

DEFF Research Database (Denmark)

den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tõnu

2013-01-01

of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate-increasing and heart rate-decreasing variants associate...

Dynamics of spectral components of heart rate variability during changes in autonomic balance

DEFF Research Database (Denmark)

Højgaard, M V; Holstein-Rathlou, N H; Agner, E

1998-01-01

Frequency domain analysis of heart rate variability (HRV) has been proposed as a semiquantitative method for assessing activities in the autonomic nervous system. We examined whether absolute powers, normalized powers, and the low frequency-to-high frequency ratio (LF/HF) derived from the HRV power...... spectrum could detect shifts in autonomic balance in a setting with low sympathetic nervous tone. Healthy subjects were examined for 3 h in the supine position during 1) control conditions (n = 12), 2) acute beta-blockade (n = 11), and 3) chronic beta-blockade (n = 10). Heart rate fell during the first 40...... min of the control session (72 +/- 2 to 64 +/- 2 beats/min; P powers of all spectral areas rose during the first 60 min in all three settings, more so with beta-blockade (P

Resting heart rate, physiological stress and disadvantage in Aboriginal and Torres Strait Islander Australians: analysis from a cross-sectional study.

Science.gov (United States)

Zhang, Alice; Hughes, Jaquelyne T; Brown, Alex; Lawton, Paul D; Cass, Alan; Hoy, Wendy; O'Dea, Kerin; Maple-Brown, Louise J

2016-02-11

Lower socioeconomic status has been linked to long-term stress, which can manifest in individuals as physiological stress. The aim was to explore the relationship between low socioeconomic status and physiological stress in Aboriginal and Torres Strait Islander Australians. Using data from the eGFR Study (a cross-sectional study of 634 Indigenous Australians in urban and remote areas of northern and central Australia), we examined associations between resting heart rate and demographic, socioeconomic, and biomedical factors. An elevated resting heart rate has been proposed as a measure of sustained stress activation and was used as a marker of physiological stress. Relationships were assessed between heart rate and the above variables using univariate and multiple regression analyses. We reported a mean resting heart rate of 74 beats/min in the cohort (mean age 45 years). On multiple regression analysis, higher heart rate was found to be independently associated with Aboriginal ethnicity, being a current smoker, having only primary level schooling, higher HbA1c and higher diastolic blood pressure (model R(2) 0.25). Elevated resting heart rate was associated with lower socioeconomic status and poorer health profile in Aboriginal and Torres Strait Islander Australians. Higher resting heart rate may be an indicator of stress and disadvantage in this population at high risk of chronic diseases.

Gender differences of heart rate variability in healthy volunteers

International Nuclear Information System (INIS)

Saleem, S.; Majeed, S.M.I.; Khan, M.A.

2012-01-01

Objective: To identify the basic values of heart rate variability in Pakistani population and to verify our hypothesis that there are gender differences in cardiovascular autonomic modulation. Methods: The descriptive cross sectional study based on convenience probability sampling was conducted at Armed Forces Institute of Cardiology/National Institute of Heart Diseases (AFIC/NIHD) Pakistan. The duration of the study was from December 2009 to July 2010. It involved 24-hour holter monitoring of 45 healthy individuals using holter electrocardiography (ECG) recorder. Heart rate variability was analysed in time (SDNN, SDANN, SDNNi, rMSSD, pNN50) and frequency domains (power, VLF, LF, and HF). Results: The time domain indices; SDNN (male=140 +- 36 ms vs. females=122 +- 33 ms; p =0.09), SDANN (male=123 +- 34 ms vs. females=111+- 34 ms; P= 0.23), SDNNi (male=64 +-19 ms vs. females=52 +- 14 ms; P= 0.03), and pNN50 (male=14 +- 10 ms vs. females=12 +- 7 ms; P= 0.43) were decreased in female volunteers when compared with males. Comparison of frequency domain indices; Total power (male=4041 +- 3150 ms/sup 2/ vs. females=2750 +- 1439 ms/sup 2/; P= 0.07), VLF (male=291 2675 ms/sup 2/ vs. females=1843 +- 928 ms/sup 2/; P= 0.06), LF (male=788 +- 397 ms/sup 2/ vs. females=556 +- 346 ms/sup 2/; P= 0.04) and HF (male=318 +- 251 ms/sup 2/ vs. females=31 277 ms/sup 2/; P= 0.94) amongst males and females showed attenuated heart rate variability in females. Of all the observed values, SDNNi and LF were found significantly (p <0.05) decreased in women. Conclusion: In healthy population, heart rate variability is low in women than men. It reflects sympathetic dominance in women in our population. (author)

Heart rate variability as determinism with jump stochastic parameters.

Science.gov (United States)

Zheng, Jiongxuan; Skufca, Joseph D; Bollt, Erik M

2013-08-01

We use measured heart rate information (RR intervals) to develop a one-dimensional nonlinear map that describes short term deterministic behavior in the data. Our study suggests that there is a stochastic parameter with persistence which causes the heart rate and rhythm system to wander about a bifurcation point. We propose a modified circle map with a jump process noise term as a model which can qualitatively capture such this behavior of low dimensional transient determinism with occasional (stochastically defined) jumps from one deterministic system to another within a one parameter family of deterministic systems.

The Role of Heart-Rate Variability Parameters in Activity Recognition and Energy-Expenditure Estimation Using Wearable Sensors.

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Park, Heesu; Dong, Suh-Yeon; Lee, Miran; Youn, Inchan

2017-07-24

Human-activity recognition (HAR) and energy-expenditure (EE) estimation are major functions in the mobile healthcare system. Both functions have been investigated for a long time; however, several challenges remain unsolved, such as the confusion between activities and the recognition of energy-consuming activities involving little or no movement. To solve these problems, we propose a novel approach using an accelerometer and electrocardiogram (ECG). First, we collected a database of six activities (sitting, standing, walking, ascending, resting and running) of 13 voluntary participants. We compared the HAR performances of three models with respect to the input data type (with none, all, or some of the heart-rate variability (HRV) parameters). The best recognition performance was 96.35%, which was obtained with some selected HRV parameters. EE was also estimated for different choices of the input data type (with or without HRV parameters) and the model type (single and activity-specific). The best estimation performance was found in the case of the activity-specific model with HRV parameters. Our findings indicate that the use of human physiological data, obtained by wearable sensors, has a significant impact on both HAR and EE estimation, which are crucial functions in the mobile healthcare system.

Soluble urokinase plasminogen activator receptor, C-reactive protein and triglyceride are associated with heart rate variability in non-diabetic Danes

DEFF Research Database (Denmark)

Intzilakis, Theodoros; Hartmann, Gro; Mouridsen, Mette R

2013-01-01

and is a predictor of poor outcome. As HRV and its determinants in non-diabetic individuals have not been studied properly, the aim of this observational study was to evaluate possible associations between HRV vs. impaired fasting glucose, insulin resistance, lipidaemia and markers of inflammation and immune......Heart rate variability (HRV) is associated with an increased risk of cardiovascular morbidity and mortality. HRV is in part a function of the activity of the autonomic nervous system and has been associated with low-grade inflammation. In patients with type 2 diabetes, HRV is decreased...

Change of Diurnal Heart Rate Patterns During Pregnancy and Lactation in Dogs (Canis familiaris

Directory of Open Access Journals (Sweden)

Häggström J

2003-09-01

Full Text Available Pregnancy and lactation involve great demands on the cardiovascular system. The purpose of this study was to investigate how the heart rate and diurnal heart rate pattern change when dogs become pregnant or lactate. Five clinically healthy female beagle dogs were mated, and delivered three to seven healthy puppies. The heart rate was investigated with 24-h ECG (Holter once during anoestrus, at 3, 5, 7 and 9 weeks of pregnancy, and at week 4 postpartum (lactation. However, at 9 weeks, the ECG could not be recorded for the fully 24 h in 4 of 5 dogs, because labour started and the dogs then appeared disturbed by the recordings. The results at this date are not included in the statistical comparison. The heart rate increased progressively during pregnancy and was still elevated at 4 weeks of lactation. During late pregnancy the difference in heart rates between daytime and nighttime became smaller, but the heart rate was significantly higher in daytime in all periods. In conclusion, the increased heart rates during pregnancy and lactation reflect increased demands on the cardiovascular system and may be important to consider in clinical practice.

Field Measurements Indicate Unexpected, Serious Underestimation of Mussel Heart Rates and Thermal Tolerance by Laboratory Studies.

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Morgana Tagliarolo

Full Text Available Attempts to predict the response of species to long-term environmental change are generally based on extrapolations from laboratory experiments that inevitably simplify the complex interacting effects that occur in the field. We recorded heart rates of two genetic lineages of the brown mussel Perna perna over a full tidal cycle in-situ at two different sites in order to evaluate the cardiac responses of the two genetic lineages present on the South African coast to temperature and the immersion/emersion cycle. "Robomussel" temperature loggers were used to monitor thermal conditions at the two sites over one year. Comparison with live animals showed that robomussels provided a good estimate of mussel body temperatures. A significant difference in estimated body temperatures was observed between the sites and the results showed that, under natural conditions, temperatures regularly approach or exceed the thermal limits of P. perna identified in the laboratory. The two P. perna lineages showed similar tidal and diel patterns of heart rate, with higher cardiac activity during daytime immersion and minimal values during daytime emersion. Comparison of the heart rates measured in the field with data previously measured in the laboratory indicates that laboratory results seriously underestimate heart rate activity, by as much as 75%, especially during immersion. Unexpectedly, field estimates of body temperatures indicated an ability to tolerate temperatures considered lethal on the basis of laboratory measurements. This suggests that the interaction of abiotic conditions in the field does not necessarily raise vulnerability to high temperatures.

Conventional heart rate variability analysis of ambulatory electrocardiographic recordings fails to predict imminent ventricular fibrillation

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Vybiral, T.; Glaeser, D. H.; Goldberger, A. L.; Rigney, D. R.; Hess, K. R.; Mietus, J.; Skinner, J. E.; Francis, M.; Pratt, C. M.

1993-01-01

OBJECTIVES. The purpose of this report was to study heart rate variability in Holter recordings of patients who experienced ventricular fibrillation during the recording. BACKGROUND. Decreased heart rate variability is recognized as a long-term predictor of overall and arrhythmic death after myocardial infarction. It was therefore postulated that heart rate variability would be lowest when measured immediately before ventricular fibrillation. METHODS. Conventional indexes of heart rate variability were calculated from Holter recordings of 24 patients with structural heart disease who had ventricular fibrillation during monitoring. The control group consisted of 19 patients with coronary artery disease, of comparable age and left ventricular ejection fraction, who had nonsustained ventricular tachycardia but no ventricular fibrillation. RESULTS. Heart rate variability did not differ between the two groups, and no consistent trends in heart rate variability were observed before ventricular fibrillation occurred. CONCLUSIONS. Although conventional heart rate variability is an independent long-term predictor of adverse outcome after myocardial infarction, its clinical utility as a short-term predictor of life-threatening arrhythmias remains to be elucidated.

Heart rate variability during sleep in healthy term newborns in the early postnatal period

International Nuclear Information System (INIS)

Doyle, O M; Korotchikova, I; Boylan, G B; Lightbody, G; Marnane, W; Kerins, D

2009-01-01

Normative time- and frequency-domain heart rate variability (HRV) measures were extracted during quiet sleep (QS) and active sleep (AS) periods in 30 healthy babies. All newborn infants studied were less than 12 h old and the sleep state was classified using multi-channel video EEG. Three bands were extracted from the heart rate (HR) spectrum: very low frequency (VLF), 0.01–0.04 Hz; low frequency (LF), 0.04–0.2 Hz, and high frequency (HF), >0.2 Hz. All metrics were averaged across all patients and per sleep state to produce a table of normative values. A noticeable peak corresponding to activity in the RSA band was found in 80% patients during QS and 0% of patients during AS, although some broadband activity was observed. The majority of HRV metrics showed a statistically significant separation between QS and AS. It can be concluded that (i) activity in the RSA band is present during QS in the healthy newborn, in the first 12 h of life, (ii) HRV measures are affected by sleep state and (iii) the averaged HRV metrics reported here could assist the interpretation of HRV data from newborns with neonatal illnesses

Effects of metronome breathing on the assessment of autonomic control using heart rate variability

NARCIS (Netherlands)

Haaksma, J; Brouwer, J; vandenBerg, MP; Dijk, WA; Dassen, WRM; Crijns, HJGM; Mulder, Lambertus; Mulder, Gysbertus

1996-01-01

Analysis of Heart Rate Variability is a non-invasive quantitative tool to study the influence of the autonomic nervous system on the heart. Rapid variations in heart rate, related to breathing are primarily mediated by the vagal limb of the autonomic nervous system. The resulting variations in heart

Relationship between heart rate and quiescent interval of the cardiac cycle in children using MRI

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Zhang, Wei [Texas Children' s Hospital, E. B. Singleton Department of Pediatric Radiology, Houston, TX (United States); Bogale, Saivivek [Baylor University Medical Center, Department of Radiology, Dallas, TX (United States); Golriz, Farahnaz [Baylor College of Medicine, Department of Radiology, Houston, TX (United States); Krishnamurthy, Rajesh [Nationwide Children' s Hospital, Department of Diagnostic Radiology, Columbus, OH (United States)

2017-11-15

Imaging the heart in children comes with the challenge of constant cardiac motion. A prospective electrocardiography-triggered CT scan allows for scanning during a predetermined phase of the cardiac cycle with least motion. This technique requires knowing the optimal quiescent intervals of cardiac cycles in a pediatric population. To evaluate high-temporal-resolution cine MRI of the heart in children to determine the relationship of heart rate to the optimal quiescent interval within the cardiac cycle. We included a total of 225 consecutive patients ages 0-18 years who had high-temporal-resolution cine steady-state free-precession sequence performed as part of a magnetic resonance imaging (MRI) or magnetic resonance angiography study of the heart. We determined the location and duration of the quiescent interval in systole and diastole for heart rates ranging 40-178 beats per minute (bpm). We performed the Wilcoxon signed rank test to compare the duration of quiescent interval in systole and diastole for each heart rate group. The duration of the quiescent interval at heart rates <80 bpm and >90 bpm was significantly longer in diastole and systole, respectively (P<.0001 for all ranges, except for 90-99 bpm [P=.02]). For heart rates 80-89 bpm, diastolic interval was longer than systolic interval, but the difference was not statistically significant (P=.06). We created a chart depicting optimal quiescent intervals across a range of heart rates that could be applied for prospective electrocardiography-triggered CT imaging of the heart. The optimal quiescent interval at heart rates <80 bpm is in diastole and at heart rates ≥90 bpm is in systole. The period of quiescence at heart rates 80-89 bpm is uniformly short in systole and diastole. (orig.)

Prolonged non-metabolic heart rate variability reduction as a physiological marker of psychological stress in daily life

NARCIS (Netherlands)

Verkuil, B.; Brosschot, J.F.; Tollenaar, M.S.; Lane, R.D.; Thayer, J.F.

2016-01-01

BACKGROUND Prolonged cardiac activity that exceeds metabolic needs can be detrimental for somatic health. Psychological stress could result in such "additional cardiac activity." PURPOSE In this study, we examined whether prolonged additional reductions in heart rate variability (AddHRVr) can be

Small-volume amnioinfusion: a potential stimulus of intrapartum fetal heart rate accelerations.

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Wax, Joseph R; Flaherty, Nina; Pinette, Michael G; Blackstone, Jacquelyn; Cartin, Angelina

2004-02-01

We describe a recurrent nonreassuring fetal heart rate pattern in which small-volume amnioinfusions apparently evoked fetal heart rate accelerations suggested fetal well-being, allowing that progressive labor that culminated in the vaginal delivery of a healthy infant.

Aerobic exercise during pregnancy and presence of fetal-maternal heart rate synchronization.

Directory of Open Access Journals (Sweden)

Peter Van Leeuwen

Full Text Available It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization.In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance.In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data.The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates.

Aerobic exercise during pregnancy and presence of fetal-maternal heart rate synchronization.

Science.gov (United States)

Van Leeuwen, Peter; Gustafson, Kathleen M; Cysarz, Dirk; Geue, Daniel; May, Linda E; Grönemeyer, Dietrich

2014-01-01

It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization. In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance. In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data. The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates.

Aerobic Exercise during Pregnancy and Presence of Fetal-Maternal Heart Rate Synchronization

Science.gov (United States)

Van Leeuwen, Peter; Gustafson, Kathleen M.; Cysarz, Dirk; Geue, Daniel; May, Linda E.; Grönemeyer, Dietrich

2014-01-01

It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization. Methods In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance. Results In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data. Conclusion The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates. PMID:25162592

Heart Rate and Energy Expenditure in Division I Field Hockey Players During Competitive Play.

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Sell, Katie M; Ledesma, Allison B

2016-08-01

Sell, KM and Ledesma, AB. Heart rate and energy expenditure in Division I field hockey players during competitive play. J Strength Cond Res 30(8): 2122-2128, 2016-The purpose of this study was to quantify energy expenditure and heart rate data for Division I female field hockey players during competitive play. Ten female Division I collegiate field hockey athletes (19.8 ± 1.6 years; 166.4 ± 6.1 cm; 58.2 ± 5.3 kg) completed the Yo-Yo intermittent endurance test to determine maximal heart rate. One week later, all subjects wore a heart rate monitor during a series of 3 matches in an off-season competition. Average heart rate (AvHR), average percentage of maximal heart rate (AvHR%), peak exercise heart rate (PExHR), and percentage of maximal heart rate (PExHR%), time spent in each of the predetermined heart rate zones, and caloric expenditure per minute of exercise (kcalM) were determined for all players. Differences between positions (backs, midfielders, and forwards) were assessed. No significant differences in AvHR, AvHR%, PExHR, PExHR%, and %TM were observed between playing positions. The AvHR% and PExHR% for each position fell into zones 4 (77-93% HRmax) and 5 (>93% HRmax), respectively, and significantly more time was spent in zone 4 compared with zones 1, 2, 3, and 5 across all players (p ≤ 0.05). The kcalM reflected very heavy intensity exercise. The results of this study will contribute toward understanding the sport-specific physiological demands of women's field hockey and has specific implications for the duration and schedule of training regimens.

Bluetooth(Registered Trademark) Heart Rate Monitors for Spaceflight

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Buxton, Roxanne E.; West, Michael R.; Kalogera, Kent L.; Hanson, Andrea M.

2016-01-01

Heart rate monitoring is required during exercise for crewmembers aboard the International Space Station (ISS) and will be for future exploration missions. The cardiovascular system must be sufficiently stressed throughout a mission to maintain the ability to perform nominal and contingency/emergency tasks. High quality heart rate data is required to accurately determine the intensity of exercise performed by the crewmembers and show maintenance of VO2max. The quality of the data collected on ISS is subject to multiple limitations and is insufficient to meet current requirements. PURPOSE: To evaluate the performance of commercially available Bluetooth® heart rate monitors (BT_HRM) and their ability to provide high quality heart rate data to monitor crew health on board ISS and during future exploration missions. METHODS: Nineteen subjects completed 30 data collection sessions of various intensities on the treadmill and/or cycle. Subjects wore several BT_HRM technologies for each testing session. One electrode-based chest strap (CS) was worn, while one or more optical sensors (OS) was worn. Subjects were instrumented with a 12-lead ECG to compare the heart rate data from the Bluetooth sensors. Each BT_RHM data set was time matched to the ECG data and a +/-5bpm threshold was applied to the difference between the two data sets. Percent error was calculated based on the number of data points outside the threshold and the total number of data points. REULTS: The electrode-based chest straps performed better than the optical sensors. The best performing CS was CS1 (1.6%error), followed by CS4 (3.3%error), CS3 (6.4%error), and CS2 (9.2%error). The OS resulted in 10.4% error for OS1 and 14.9% error for OS2. CONCLUSIONS: The highest quality data came from CS1, unfortunately it has been discontinued by the manufacturer. The optical sensors have not been ruled out for use, but more investigation is needed to determine how to get the best quality data. CS2 will be used in an

Impaired chronotropic response to physical activities in heart failure patients.

Science.gov (United States)

Shen, Hong; Zhao, Jianrong; Zhou, Xiaohong; Li, Jingbo; Wan, Qing; Huang, Jing; Li, Hui; Wu, Liqun; Yang, Shungang; Wang, Ping

2017-05-25

While exercise-based cardiac rehabilitation has a beneficial effect on heart failure hospitalization and mortality, it is limited by the presence of chronotropic incompetence (CI) in some patients. This study explored the feasibility of using wearable devices to assess impaired chronotropic response in heart failure patients. Forty patients with heart failure (left ventricular ejection fraction, LVEF: 44.6 ± 5.8; age: 54.4 ± 11.7) received ECG Holter and accelerometer to monitor heart rate (HR) and physical activities during symptom-limited treadmill exercise testing, 6-min hall walk (6MHW), and 24-h daily living. CI was defined as maximal HR during peak exercise testing failing to reach 70% of age-predicted maximal HR (APMHR, 220 - age). The correlation between HR and physical activities in Holter-accelerometer recording was analyzed. Of 40 enrolled patients, 26 were able to perform treadmill exercise testing. Based on exercise test reports, 13 (50%) of 26 patients did not achieve at least 70% of APMHR (CI patients). CI patients achieved a lower % APMHR (62.0 ± 6.3%) than non-CI patients who achieved 72.0 ± 1.2% of APMHR (P failure patients who took treadmill exercise testing. The wearable Holter-accelerometer recording could help to identify impaired chronotropic response to physical activities in heart failure patients. ClinicalTrials.gov ID NCT02358603 . Registered 16 May 2014.

Paradoxical response to an emotional task: Trait characteristics and heart-rate dynamics

NARCIS (Netherlands)

Balocchia, R.; Varanini, M.; Paoletti, G.; Mecacci, G.; Santarcangelo, E.L.

2015-01-01

The present study evaluated the heart-rate dynamics of subjects reporting decreased (responders) or paradoxically increased relaxation (nonresponders) at the end of a threatening movie. Heart-rate dynamics were characterized by indices extracted through recurrence quantification analysis (RQA) and

Use of a prototype pulse oximeter for time series analysis of heart rate variability

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González, Erika; López, Jehú; Hautefeuille, Mathieu; Velázquez, Víctor; Del Moral, Jésica

2015-05-01

This work presents the development of a low cost pulse oximeter prototype consisting of pulsed red and infrared commercial LEDs and a broad spectral photodetector used to register time series of heart rate and oxygen saturation of blood. This platform, besides providing these values, like any other pulse oximeter, processes the signals to compute a power spectrum analysis of the patient heart rate variability in real time and, additionally, the device allows access to all raw and analyzed data if databases construction is required or another kind of further analysis is desired. Since the prototype is capable of acquiring data for long periods of time, it is suitable for collecting data in real life activities, enabling the development of future wearable applications.

Towards 24/7 continuous heart rate monitoring.

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Tarniceriu, Adrian; Parak, Jakub; Renevey, Philippe; Nurmi, Marko; Bertschi, Mattia; Delgado-Gonzalo, Ricard; Korhonen, Ilkka

2016-08-01

Heart rate (HR) and HR variability (HRV) carry rich information about physical activity, mental and physical load, physiological status, and health of an individual. When combined with activity monitoring and personalized physiological modelling, HR/HRV monitoring may be used for monitoring of complex behaviors and impact of behaviors and external factors on the current physiological status of an individual. Optical HR monitoring (OHR) from wrist provides a comfortable and unobtrusive method for HR/HRV monitoring and is better adhered by users than traditional ECG electrodes or chest straps. However, OHR power consumption is significantly higher than that for ECG based methods due to the measurement principle based on optical illumination of the tissue. We developed an algorithmic approach to reduce power consumption of the OHR in 24/7 HR trending. We use continuous activity monitoring and a fast converging frequency domain algorithm to derive a reliable HR estimate in 7.1s (during outdoor sports, in average) to 10.0s (during daily life). The method allows >80% reduction in power consumption in 24/7 OHR monitoring when average HR monitoring is targeted, without significant reduction in tracking accuracy.

HEART RATE RECOVERY AFTER EXERCISE AND NEURAL REGULATION OF HEART RATE VARIABILITY IN 30-40 YEAR OLD FEMALE MARATHON RUNNERS

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Toshio Matsuoka

2005-03-01

Full Text Available The aim of the present study was to examine the effects of endurance training on heart rate (HR recovery after exercise and cardiac autonomic nervous system (ANS modulation in female marathon runners by comparing with untrained controls. Six female marathon runners (M group aged 32-40 years and eight age-matched untrained females (C group performed a maximum-effort treadmill running exercise. Maximal oxygen uptake (VO2max was measured during the exercise with a gas analyzer connected to subjects through a face mask. Heart rate, blood pressure and blood lactate were measured before and after the exercise. Rating of perceived exertion (RPE to the exercise was obtained immediately after the exercise. Holter ECG was recorded and analyzed with power spectral analysis of heart rate variability (HRV to investigate the cardiac ANS modulation. The M group had significantly higher VO2max, faster HR recovery after exercise, higher Mean RR, SDRR, HF power and lower LF/HF ratio at rest compared with the C group. The M group also presented greater percent decrease of blood pressure after exercise, although their blood pressure after exercise was higher than the C group. It is suggested that endurance training induced significant alterations in cardiac ANS modulation at rest and significant acceleration of HR recovery after exercise in female marathon runners. Faster HR recovery after exercise in the female marathon runners should result from their higher levels of HRV, higher aerobic capacity and exaggerated blood pressure response to exercise compared with untrained controls.

Effects of Exercise Training on Heart Rate Variability in Chagas Heart Disease

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Bruno Ramos Nascimento

2014-09-01

Full Text Available Background: Heart rate variability (HRV is a marker of autonomic dysfunction severity. The effects of physical training on HRV indexes in Chagas heart disease (CHD are not well established. Objective: To evaluate the changes in HRV indexes in response to physical training in CHD. Methods: Patients with CHD and left ventricular (LV dysfunction, physically inactive, were randomized either to the intervention (IG, N = 18 or control group (CG, N = 19. The IG participated in a 12-week exercise program consisting of 3 sessions/week. Results: Mean age was 49.5 ± 8 years, 59% males, mean LVEF was 36.3 ± 7.8%. Baseline HRV indexes were similar between groups. From baseline to follow-up, total power (TP: 1653 (IQ 625 - 3418 to 2794 (1617 - 4452 ms, p = 0.02 and very low frequency power: 586 (290 - 1565 to 815 (610 - 1425 ms, p = 0.047 increased in the IG, but not in the CG. The delta (post - pre HRV indexes were similar: SDNN 11.5 ± 30.0 vs. 3.7 ± 25.1 ms. p = 0.10; rMSSD 2 (6 - 17 vs. 1 (21 - 9 ms. p = 0.43; TP 943 (731 - 3130 vs. 1780 (921 - 2743 Hz. p = 0.46; low frequency power (LFP 1.0 (150 - 197 vs. 60 (111 - 146 Hz. p = 0.85; except for high frequency power, which tended to increase in the IG: 42 (133 - 92 vs. 79 (61 - 328 Hz. p = 0.08. Conclusion: In the studied population, the variation of HRV indexes was similar between the active and inactive groups. Clinical improvement with physical activity seems to be independent from autonomic dysfunction markers in CHD.

Heart rate variability based on risk stratification for type 2 diabetes mellitus.

Science.gov (United States)

Silva-E-Oliveira, Julia; Amélio, Pâmela Marina; Abranches, Isabela Lopes Laguardia; Damasceno, Dênis Derly; Furtado, Fabianne

2017-01-01

To evaluate heart rate variability among adults with different risk levels for type 2 diabetes mellitus. The risk for type 2 diabetes mellitus was assessed in 130 participants (89 females) based on the questionnaire Finnish Diabetes Risk Score and was classified as low risk (n=26), slightly elevated risk (n=41), moderate risk (n=27) and high risk (n=32). To measure heart rate variability, a heart-rate monitor Polar S810i® was employed to obtain RR series for each individual, at rest, for 5 minutes, followed by analysis of linear and nonlinear indexes. The groups at higher risk of type 2 diabetes mellitus had significantly lower linear and nonlinear heart rate variability indexes. The individuals at high risk for type 2 diabetes mellitus have lower heart rate variability. Avaliar a variabilidade da frequência cardíaca em adultos com diferentes níveis de risco para diabetes mellitus tipo 2. O grau de risco para diabetes mellitus tipo 2 de 130 participantes (41 homens) foi avaliado pelo questionário Finnish Diabetes Risk Score. Os participantes foram classificados em baixo risco (n=26), risco levemente elevado (n=41), risco moderado (n=27) e alto risco (n=32). Para medir a variabilidade da frequência cardíaca, utilizou-se o frequencímetro Polar S810i® para obter séries de intervalo RR para cada indivíduo, em repouso, durante 5 minutos; posteriormente, realizou-se análise por meio de índices lineares e não-lineares. O grupo com maior risco para diabetes mellitus tipo 2 teve uma diminuição significante nos índices lineares e não-lineares da variabilidade da frequência cardíaca. Os resultados apontam que indivíduos com risco alto para diabetes mellitus tipo 2 tem menor variabilidade da frequência cardíaca. To evaluate heart rate variability among adults with different risk levels for type 2 diabetes mellitus. The risk for type 2 diabetes mellitus was assessed in 130 participants (89 females) based on the questionnaire Finnish Diabetes Risk Score

Classic electrocardiogram-based and mobile technology derived approaches to heart rate variability are not equivalent.

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Guzik, Przemyslaw; Piekos, Caroline; Pierog, Olivia; Fenech, Naiman; Krauze, Tomasz; Piskorski, Jaroslaw; Wykretowicz, Andrzej

2018-05-01

We compared classic ECG-derived versus a mobile approach to heart rate variability (HRV) measurement. 29 young adult healthy volunteers underwent a simultaneous recording of heart rate using an ECG and a chest heart rate monitor at supine rest, during mental stress and active standing. Mean RR interval, Standard Deviation of Normal-to-Normal (SDNN) of RR intervals, and Root Mean Square of the Successive Differences (RMSSD) between RR intervals were computed in 168 pairs of 5-minute epochs by in-house software on a PC (only sinus beats) and by mobile application "ELITEHRV" on a smartphone (no beat type identification). ECG analysis showed that 33.9% of the recordings contained at least one non-sinus beat or artefact, the mobile app did not report this. The mean RR intervals were significantly longer (p = 0.0378), while SDNN (p = 0.0001) and RMSSD (p = 0.0199) were smaller for the mobile approach. Measures of identical HRV parameters by ECG-based and mobile approaches are not equivalent. Copyright © 2018 Elsevier B.V. All rights reserved.

Heart rate variability in normal-weight patients with polycystic ovary syndrome.

Science.gov (United States)

Kilit, Celal; Paşalı Kilit, Türkan

2017-05-01

Polycystic ovary syndrome (PCOS) is an endocrine disease closely related to several risk factors of cardiovascular disease. Obese women with PCOS show altered autonomic modulation. The results of studies investigating cardiac autonomic functions of normal-weight women with PCOS are conflicting. The aim of the study was to assess the reactivity of cardiac sympathovagal balance in normal-weight women with PCOS by heart rate variability analysis. We examined the heart rate variability in 60 normal-weight women with PCOS and compared them with that in 60 age-matched healthy women having a similar metabolic profile. Time and frequency domain parameters of heart rate variability were analyzed based on 5-min-long continuous electrocardiography recordings for the following 3 periods: (1) during rest in supine position, (2) during controlled breathing, and (3) during isometric handgrip exercise. Time and frequency domain parameters of heart rate variability for the 3 periods assessed were similar in the two groups. Although modified Ferriman-Gallwey score and serum testosterone and luteinizing hormone levels were significantly higher in women with PCOS, homeostatic model assessment-insulin resistance (HOMA-IR) was not different the between the PCOS and control groups. There were no significant correlations between serum testosterone levels and heart rate variability parameters among the study population. The findings of this study suggest that the reactivity of cardiac sympathovagal balance is not altered in normal-weight women with PCOS having a normal HOMA-IR.

Abnormal heart rate recovery and deficient chronotropic response after submaximal exercise in young Marfan syndrome patients.

Science.gov (United States)

Peres, Paulo; Carvalho, Antônio C; Perez, Ana Beatriz A; Medeiros, Wladimir M

2016-10-01

Marfan syndrome patients present important cardiac structural changes, ventricular dysfunction, and electrocardiographic changes. An abnormal heart rate response during or after exercise is an independent predictor of mortality and autonomic dysfunction. The aim of the present study was to compare heart rate recovery and chronotropic response obtained by cardiac reserve in patients with Marfan syndrome subjected to submaximal exercise. A total of 12 patients on β-blocker therapy and 13 off β-blocker therapy were compared with 12 healthy controls. They were subjected to submaximal exercise with lactate measurements. The heart rate recovery was obtained in the first minute of recovery and corrected for cardiac reserve and peak lactate concentration. Peak heart rate (141±16 versus 155±17 versus 174±8 bpm; p=0.001), heart rate reserve (58.7±9.4 versus 67.6±14.3 versus 82.6±4.8 bpm; p=0.001), heart rate recovery (22±6 versus 22±8 versus 34±9 bpm; p=0.001), and heart rate recovery/lactate (3±1 versus 3±1 versus 5±1 bpm/mmol/L; p=0.003) were different between Marfan groups and controls, respectively. All the patients with Marfan syndrome had heart rate recovery values below the mean observed in the control group. The absolute values of heart rate recovery were strongly correlated with the heart rate reserve (r=0.76; p=0.001). Marfan syndrome patients have reduced heart rate recovery and chronotropic deficit after submaximal exercise, and the chronotropic deficit is a strong determinant of heart rate recovery. These changes are suggestive of autonomic dysfunction.

Reduced heart rate variability in social anxiety disorder: associations with gender and symptom severity.

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Gail A Alvares

Full Text Available BACKGROUND: Polyvagal theory emphasizes that autonomic nervous system functioning plays a key role in social behavior and emotion. The theory predicts that psychiatric disorders of social dysfunction are associated with reduced heart rate variability, an index of autonomic control, as well as social inhibition and avoidance. The purpose of this study was to examine whether heart rate variability was reduced in treatment-seeking patients diagnosed with social anxiety disorder, a disorder characterized by social fear and avoidance. METHODS: Social anxiety patients (n = 53 were recruited prior to receiving psychological therapy. Healthy volunteers were recruited through the University of Sydney and the general community and were matched by gender and age (n = 53. Heart rate variability was assessed during a five-minute recording at rest, with participants completing a range of self-report clinical symptom measures. RESULTS: Compared to controls, participants with social anxiety exhibited significant reductions across a number of heart rate variability measures. Reductions in heart rate variability were observed in females with social anxiety, compared to female controls, and in patients taking psychotropic medication compared to non-medicated patients. Finally, within the clinical group, we observed significant associations between reduced heart rate variability and increased social interaction anxiety, psychological distress, and harmful alcohol use. CONCLUSIONS: The results of this study confirm that social anxiety disorder is associated with reduced heart rate variability. Resting state heart rate variability may therefore be considered a marker for social approach-related motivation and capacity for social engagement. Additionally, heart rate variability may provide a useful biomarker to explain underlying difficulties with social approach, impaired stress regulation, and behavioral inhibition, especially in disorders associated with

Heart Rate Variability as an Indicator of Chronic Stress Caused by Lameness in Dairy Cows.

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Levente Kovács

Full Text Available Most experimental studies on animal stress physiology have focused on acute stress, while chronic stress, which is also encountered in intensive dairy cattle farming--e.g. in case of lameness--, has received little attention. We investigated heart rate (HR and heart rate variability (HRV as indicators of the autonomic nervous system activity and fecal glucocorticoid concentrations as the indicator of the hypothalamic-pituitary-adrenal axis activity in lame (with locomotion scores 4 and 5; n = 51 and non-lame (with locomotion scores 1 and 2; n = 52 Holstein-Friesian cows. Data recorded during the periods of undisturbed lying--representing baseline cardiac activity--were involved in the analysis. Besides linear analysis methods of the cardiac inter-beat interval (time-domain geometric, frequency domain and Poincaré analyses non-linear HRV parameters were also evaluated. With the exception of standard deviation 1 (SD1, all HRV indices were affected by lameness. Heart rate was lower in lame cows than in non-lame ones. Vagal tone parameters were higher in lame cows than in non-lame animals, while indices of the sympathovagal balance reflected on a decreased sympathetic activity in lame cows. All geometric and non-linear HRV measures were lower in lame cows compared to non-lame ones suggesting that chronic stress influenced linear and non-linear characteristics of cardiac function. Lameness had no effect on fecal glucocorticoid concentrations. Our results demonstrate that HRV analysis is a reliable method in the assessment of chronic stress, however, it requires further studies to fully understand the elevated parasympathetic and decreased sympathetic tone in lame animals.

Increased heart rate variability but normal resting metabolic rate in hypocretin/orexin-deficient human narcolepsy.

NARCIS (Netherlands)

Fronczek, R.; Overeem, S.; Reijntjes, R.; Lammers, G.J.; Dijk, J.G.M.; Pijl, H.

2008-01-01

STUDY OBJECTIVES: We investigated autonomic balance and resting metabolic rate to explore their possible involvement in obesity in hypocretin/orexin-deficient narcoleptic subjects. METHODS: Resting metabolic rate (using indirect calorimetry) and variability in heart rate and blood pressure were

[Corrective effect of aromatherapy on indices of heart rate variability in students under exam stress conditions].

Science.gov (United States)

Abrahamyan, H T; Minasyan, S M

2016-01-01

There were investigated changes in indices of the activity of regulatory mechanisms of heart rhythm in student under exam stress conditions and the possibility of their correction with aid of aromatherapy. The examination stress was established to be accompanied by pronounced shifts of integral and spectral indices of heart rhythm in students, indicating to the activation of the sympathetic circuit of Autonomic Nervous System in conditions of examination stress. A positive, relaxation impact of the essential oil of orange on the investigated indices was also recorded. The latter is expressed by weakly pronounced changes or lack of them in data of integral and spectral heart rate indices in students from the experimental group, that indicates to the stabilizing effect of used ethereal oil on the psycho-physiological state of students in conditions of exam stress

The lateral paragigantocellular nucleus modulates parasympathetic cardiac neurons: a mechanism for rapid eye movement sleep-dependent changes in heart rate.

Science.gov (United States)

Dergacheva, Olga; Wang, Xin; Lovett-Barr, Mary R; Jameson, Heather; Mendelowitz, David

2010-08-01

Rapid eye movement (REM) sleep is generally associated with a withdrawal of parasympathetic activity and heart rate increases; however, episodic vagally mediated heart rate decelerations also occur during REM sleep. This alternating pattern of autonomic activation provides a physiological basis for REM sleep-induced cardiac arrhythmias. Medullary neurons within the lateral paragigantocellular nucleus (LPGi) are thought to be active after REM sleep recovery and play a role in REM sleep control. In proximity to the LPGi are parasympathetic cardiac vagal neurons (CVNs) within the nucleus ambiguus (NA), which are critical for controlling heart rate. This study examined brain stem pathways that may mediate REM sleep-related reductions in parasympathetic cardiac activity. Electrical stimulation of the LPGi evoked inhibitory GABAergic postsynaptic currents in CVNs in an in vitro brain stem slice preparation in rats. Because brain stem cholinergic mechanisms are involved in REM sleep regulation, we also studied the role of nicotinic neurotransmission in modulation of GABAergic pathway from the LGPi to CVNs. Application of nicotine diminished the GABAergic responses evoked by electrical stimulation. This inhibitory effect of nicotine was prevented by the alpha7 nicotinic receptor antagonist alpha-bungarotoxin. Moreover, hypoxia/hypercapnia (H/H) diminished LPGi-evoked GABAergic current in CVNs, and this inhibitory effect was also prevented by alpha-bungarotoxin. In conclusion, stimulation of the LPGi evokes an inhibitory pathway to CVNs, which may constitute a mechanism for the reduced parasympathetic cardiac activity and increase in heart rate during REM sleep. Inhibition of this pathway by nicotinic receptor activation and H/H may play a role in REM sleep-related and apnea-associated bradyarrhythmias.

Determination of heart rate variability with an electronic stethoscope.

Science.gov (United States)

Kamran, Haroon; Naggar, Isaac; Oniyuke, Francisca; Palomeque, Mercy; Chokshi, Priya; Salciccioli, Louis; Stewart, Mark; Lazar, Jason M

2013-02-01

Heart rate variability (HRV) is widely used to characterize cardiac autonomic function by measuring beat-to-beat alterations in heart rate. Decreased HRV has been found predictive of worse cardiovascular (CV) outcomes. HRV is determined from time intervals between QRS complexes recorded by electrocardiography (ECG) for several minutes to 24 h. Although cardiac auscultation with a stethoscope is performed routinely on patients, the human ear cannot detect heart sound time intervals. The electronic stethoscope digitally processes heart sounds, from which cardiac time intervals can be obtained. Accordingly, the objective of this study was to determine the feasibility of obtaining HRV from electronically recorded heart sounds. We prospectively studied 50 subjects with and without CV risk factors/disease and simultaneously recorded single lead ECG and heart sounds for 2 min. Time and frequency measures of HRV were calculated from R-R and S1-S1 intervals and were compared using intra-class correlation coefficients (ICC). The majority of the indices were strongly correlated (ICC 0.73-1.0), while the remaining indices were moderately correlated (ICC 0.56-0.63). In conclusion, we found HRV measures determined from S1-S1 are in agreement with those determined by single lead ECG, and we demonstrate and discuss differences in the measures in detail. In addition to characterizing cardiac murmurs and time intervals, the electronic stethoscope holds promise as a convenient low-cost tool to determine HRV in the hospital and outpatient settings as a practical extension of the physical examination.

Interchangeability of electrocardiography and blood pressure measurement for determining heart rate and heart rate variability in free-moving domestic pigs in various behavioral contexts

Directory of Open Access Journals (Sweden)

Annika eKrause

2015-11-01

Full Text Available This study assessed the interchangeability between heart rate (HR and heart rate variability (HRV measures derived from a series of interbeat intervals (IBIs recorded via electrocardiogram (ECG and intra-arterial blood pressure (BP in various behavioral contexts. Five minutes of simultaneously recorded IBIs from ECG and BP signals in 11 female domestic pigs during resting, feeding and active behavior were analyzed. Comparisons were made for measures of HR, SDNN (the standard deviation of IBIs and RMSSD (the root mean of the squared distances of subsequent IBIs derived from ECG and BP signals for each behavior category using statistical procedures with different explanatory power (linear regression, intraclass correlation coefficient (ICC, Bland and Altman plots and analysis of variance (ANOVA. Linear regression showed a strong relationship for HR during all behaviors and for HRV during resting. Excellent ICCs (lower 95% CI > 0.75 and narrow limits of agreement (LoA in all behavior categories were found for HR. ICCs for HRV reached the critical lower 95% CI value of 0.75 only during resting. Using Bland and Altman plots, HRV agreement was unacceptable for all of the behavior categories. ANOVA showed significant differences between the methods in terms of HRV. BP systematically overestimated HRV compared with ECG. Our findings reveal that HR data recorded via BP agree well those recorded using ECG independently of the activity of the subject, whereas ECG and BP cannot be used interchangeably in the context of HRV in free-moving domestic pigs.

Estimating Energy Expenditure from Heart Rate in Older Adults: A Case for Calibration

OpenAIRE

Schrack, Jennifer A.; Zipunnikov, Vadim; Goldsmith, Jeff; Bandeen-Roche, Karen; Crainiceanu, Ciprian M.; Ferrucci, Luigi

2014-01-01

Background Accurate measurement of free-living energy expenditure is vital to understanding changes in energy metabolism with aging. The efficacy of heart rate as a surrogate for energy expenditure is rooted in the assumption of a linear function between heart rate and energy expenditure, but its validity and reliability in older adults remains unclear. Objective To assess the validity and reliability of the linear function between heart rate and energy expenditure in older adults using diffe...

Heart rate variability analysis in postural orthostatic tachycardia syndrome: a case report

Directory of Open Access Journals (Sweden)

Raffaele Calabrò

2006-09-01

Full Text Available The authors present a case of 36 year old male patient with idiopathic postural orthostatic tachycardia syndrome (POTS diagnosed during head-up tilt testing. Power spectral analysis of heart rate variability (HRV during the tilt test revealed that the ratio of low and high frequency powers (LF/HF increased with the onset of orthostatic intolerance. This analysis confirmed in our patient a strong activation in sympathetic tone.

Heart rate profiles and energy cost of locomotion during cross-country skiing races.

Science.gov (United States)

Mognoni, P; Rossi, G; Gastaldelli, F; Canclini, A; Cotelli, F

2001-07-01

The purpose of this study was to compare heart rate responses and speed in two cross-country skiing races, which were run by seven male and seven female subjects by using classic and free style. Heart rates and skiing velocities were analyzed over flat, uphill and downhill sections, which were run from one to three times. Heart rates were higher in uphill sections than in flat sections; a steady-state heart rate was never reached in the downhill section. When the same uphill section was repeated, the heart rate tended to increase but the speed to decrease. Oxygen uptake (VO2) was calculated from heart rate:VO2 ratio, measured during uphill walking with the aid of poles. The mean (SD) energy cost of locomotion (i.e., the ratio between net VO2 and speed) was 162.1 (9.4) ml.km(-1).kg(-1) and 147.7 (7.1) ml.km(-1).kg(-1) when male subjects ran the flat section after first downhill by using classic and free style, respectively. Females had lower values for VO2 and speed, but similar energy costs. In general, the variability of the energy cost of locomotion in skiers of a similar competitive level is of the same order as that found in uphill walking on a treadmill.

Assessing Metabolic Syndrome Through Increased Heart Rate During Exercise

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Masoumeh Sadeghi

2016-12-01

Full Text Available The present study aimed to assess changes in resting and maximum heart rates as primary indicators of cardiac autonomic function in metabolic syndrome (MetS patients and to determine their value for discriminating MetS from non-MetS. 468 participants were enrolled in this cross-sectional study and assessed according to the updated adult treatment panel III (ATP-III definition of MetS. Resting and maximum heart rates were recorded following the Bruce protocol during an exercise. A receiver operating characteristic (ROC curve was used to identify the best cutoff point for discriminating MetS from the non-MetS state. 194 participants (41.5% were diagnosed as MetS. The mean resting heart rate (RHR was not statistically different between the two groups (P=0.078. However, the mean maximum heart (MHR rate was considerably higher in participants with MetS (142.37±14.84 beats per min compared to the non-MetS group (134.62±21.63 beats per min (P<0.001. In the MetS group, the MHR was positively correlated with the serum triglyceride level (β=0.185, P=0.033 and was inversely associated with age (β=-0.469, P<0.001. The MHR had a moderate value for discriminating MetS from the non-MetS state (c=0.580, P=0.004 with the optimal cutoff point of 140 beats per min. In MetS patients, the MHR was significantly greater compared to non-MetS subjects and was directly correlated with serum triglyceride levels and inversely with advanced age. Moreover, MHR can be used as a suspicious indicator for identifying MetS.

Assessing Metabolic Syndrome Through Increased Heart Rate During Exercise.

Science.gov (United States)

Sadeghi, Masoumeh; Gharipour, Mojgan; Nezafati, Pouya; Shafie, Davood; Aghababaei, Esmaeil; Sarrafzadegan, Nizal

2016-11-01

The present study aimed to assess changes in resting and maximum heart rates as primary indicators of cardiac autonomic function in metabolic syndrome (MetS) patients and to determine their value for discriminating MetS from non-MetS. 468 participants were enrolled in this cross-sectional study and assessed according to the updated adult treatment panel III (ATP-III) definition of MetS. Resting and maximum heart rates were recorded following the Bruce protocol during an exercise. A receiver operating characteristic (ROC) curve was used to identify the best cutoff point for discriminating MetS from the non-MetS state. 194 participants (41.5%) were diagnosed as MetS. The mean resting heart rate (RHR) was not statistically different between the two groups (P=0.078). However, the mean maximum heart (MHR) rate was considerably higher in participants with MetS (142.37±14.84 beats per min) compared to the non-MetS group (134.62±21.63 beats per min) (P<0.001). In the MetS group, the MHR was positively correlated with the serum triglyceride level (β=0.185, P=0.033) and was inversely associated with age (β=-0.469, P<0.001). The MHR had a moderate value for discriminating MetS from the non-MetS state (c=0.580, P=0.004) with the optimal cutoff point of 140 beats per min. In MetS patients, the MHR was significantly greater compared to non-MetS subjects and was directly correlated with serum triglyceride levels and inversely with advanced age. Moreover, MHR can be used as a suspicious indicator for identifying MetS.

A Meta-analysis on Resting State High-frequency Heart Rate Variability in Bulimia Nervosa.

Science.gov (United States)

Peschel, Stephanie K V; Feeling, Nicole R; Vögele, Claus; Kaess, Michael; Thayer, Julian F; Koenig, Julian

2016-09-01

Autonomic nervous system function is altered in eating disorders. We aimed to quantify differences in resting state vagal activity, indexed by high-frequency heart rate variability comparing patients with bulimia nervosa (BN) and healthy controls. A systematic search of the literature to identify studies eligible for inclusion and meta-analytical methods were applied. Meta-regression was used to identify potential covariates. Eight studies reporting measures of resting high-frequency heart rate variability in individuals with BN (n = 137) and controls (n = 190) were included. Random-effects meta-analysis revealed a sizeable main effect (Z = 2.22, p = .03; Hedge's g = 0.52, 95% CI [0.06;0.98]) indicating higher resting state vagal activity in individuals with BN. Meta-regression showed that body mass index and medication intake are significant covariates. Findings suggest higher vagal activity in BN at rest, particularly in unmedicated samples with lower body mass index. Potential mechanisms underlying these findings and implications for routine clinical care are discussed. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

ISOMETRIC EXERCISE AND ITS EFFECT ON BLOOD PRESSURE AND HEART RATE, BEFORE AND AFTER TRAINING IN YOUNG HEALTHY MALES

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Mohammed

2015-05-01

Full Text Available INTRODUCTION: Isometric exercise is a normal part of everyday activities and many occupational tasks. Preventive services are important as they give physicians an opportunity and responsibility to promote regular physical activity, reduc e high blood pressure, and help in weight control. Physical inactivity is recognized as a risk factor for coronary artery disease. Regular aerobic physical activity increases exercise capacity and plays a role in both primary and secondary prevention of ca rdiovascular disease. OBJECTIVE: To assess the effects of isometric handgrip training on Blood pressure and Heart rate in healthy young males in the age group of 18 - 22 years. MATERIALS AND METHOD : Study subjects consisted of 30 healthy adult males in the age group of 18 - 22 yrs. Age and sex matched adults who were not active in sports or in physical activities constituted the control group (n=30. Blood pressure and heart rate were recorded and eval uated after a defined protocol of handgrip sustained static (isometric contractions performed with the handgrip dynamometer at Rest and Post Exercise. BP and HR were recorded with the help of automated blood pressure monitor and power lab 8/30 series inst rument available in the Department of Physiology , Navodaya Medical college, Raichur. RESULTS: There was no change in Resting Blood pressure and Heart rate between the subject and control group before the training sessions. There was significant decrease in resting Blood pressure and Heart rate in trained subject group when compared to untrained control group after 5 weeks of training sessions. CONCLUSION : Isometric hand grip training is effective in lowering arterial pressure in normotensive subjects. Isome tric training may be an effective intervention in the prevention and treatment of hypertension

256-slice CT coronary angiography in atrial fibrillation: The impact of mean heart rate and heart rate variability on image quality

Energy Technology Data Exchange (ETDEWEB)

Chen, Liang-Kuang [Department of Radiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); College of Medicine, Fu Jen Catholic University, Taipei, Taiwan (China); Hsu, Shih-Ming [Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan (China); Mok, Greta S.P. [Department of Electrical and Electronics Engineering, Faculty of Science and Technology, University of Macau, Macau (China); Law, Wei-Yip; Lu, Kun-Mu [Department of Radiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Yang, Ching-Ching, E-mail: g39220003@yahoo.com.tw [Department of Radiological Technology, Tzu Chi College of Technology, 880, Sec.2, Chien-kuo Rd. Hualien 970, Taiwan (China); Wu, Tung-Hsin, E-mail: tung@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, 155 Li-Nong St., Sec. 2, Taipei 112, Taiwan (China)

2011-08-21

Objective: The aim of this study was to evaluate the image quality of 256-MDCT in atrial fibrillation and to compare the findings with those among patients in sinus rhythm. Materials: All reconstructed images were evaluated by two independent experienced readers blinded to patient information, heart rate, and ECG results to assess the diagnostic quality of images of the coronary artery segments using axial images, multi-planar reformations, maximum intensity projections, and volume rendering technique. Results: No statistical significance was detected in terms of the overall image quality between patients in sinus rhythm and with atrial fibrillation. Pearson's correlation analysis showed no significant association between image quality and mean heart rate no matter for patients in sinus rhythm or with atrial fibrillation. Similarly, there was no correlation between image quality and heart rate variability for either patients in sinus rhythm or with atrial fibrillation. Our results showed that the optimal reconstruction window depends on patient's HR, and the pattern for patients in atrial fibrillation is similar to that obtained from non-atrial fibrillation patients. Conclusion: This study shows the potential of using 256-MDCT coronary angiography in patients with atrial fibrillation. Our results suggest that when appropriate reconstruction timing window is applied, patients with atrial fibrillation do not have to be excluded from MDCT coronary angiographic examinations.

256-slice CT coronary angiography in atrial fibrillation: The impact of mean heart rate and heart rate variability on image quality

International Nuclear Information System (INIS)

Chen, Liang-Kuang; Hsu, Shih-Ming; Mok, Greta S.P.; Law, Wei-Yip; Lu, Kun-Mu; Yang, Ching-Ching; Wu, Tung-Hsin

2011-01-01

Objective: The aim of this study was to evaluate the image quality of 256-MDCT in atrial fibrillation and to compare the findings with those among patients in sinus rhythm. Materials: All reconstructed images were evaluated by two independent experienced readers blinded to patient information, heart rate, and ECG results to assess the diagnostic quality of images of the coronary artery segments using axial images, multi-planar reformations, maximum intensity projections, and volume rendering technique. Results: No statistical significance was detected in terms of the overall image quality between patients in sinus rhythm and with atrial fibrillation. Pearson's correlation analysis showed no significant association between image quality and mean heart rate no matter for patients in sinus rhythm or with atrial fibrillation. Similarly, there was no correlation between image quality and heart rate variability for either patients in sinus rhythm or with atrial fibrillation. Our results showed that the optimal reconstruction window depends on patient's HR, and the pattern for patients in atrial fibrillation is similar to that obtained from non-atrial fibrillation patients. Conclusion: This study shows the potential of using 256-MDCT coronary angiography in patients with atrial fibrillation. Our results suggest that when appropriate reconstruction timing window is applied, patients with atrial fibrillation do not have to be excluded from MDCT coronary angiographic examinations.

Changes of heart rate variability and prefrontal oxygenation during Tai Chi practice versus arm ergometer cycling

OpenAIRE

Lu, Xi; Hui-Chan, Christina Wan-Ying; Tsang, William Wai-Nam

2016-01-01

[Purpose] Exercise has been shown to improve cardiovascular fitness and cognitive function. Whether the inclusion of mind over exercise would increase parasympathetic control of the heart and brain activities more than general exercise at a similar intensity is not known. The aim of this study was to compare the effects of Tai Chi (mind-body exercise) versus arm ergometer cycling (body-focused exercise) on the heart rate variability and prefrontal oxygenation level. [Subjects and Methods] A T...

Physical activity increases survival after heart valve surgery

DEFF Research Database (Denmark)

Lund, K.; Sibilitz, Kirstine Lærum; Kikkenborg Berg, Selina

2016-01-01

physical activity levels 6-12 months after heart valve surgery and (1) survival, (2) hospital readmission 18-24 months after surgery and (3) participation in exercise-based cardiac rehabilitation. METHODS: Prospective cohort study with registry data from The CopenHeart survey, The Danish National Patient......OBJECTIVES: Increased physical activity predicts survival and reduces risk of readmission in patients with coronary heart disease. However, few data show how physical activity is associated with survival and readmission after heart valve surgery. Objective were to assess the association between...... Register and The Danish Civil Registration System of 742 eligible patients. Physical activity was quantified with the International Physical Activity Questionnaire and analysed using Kaplan-Meier analysis and Cox regression and logistic regression methods. RESULTS: Patients with a moderate to high physical...

Robust efficient estimation of heart rate pulse from video

Science.gov (United States)

Xu, Shuchang; Sun, Lingyun; Rohde, Gustavo Kunde

2014-01-01

We describe a simple but robust algorithm for estimating the heart rate pulse from video sequences containing human skin in real time. Based on a model of light interaction with human skin, we define the change of blood concentration due to arterial pulsation as a pixel quotient in log space, and successfully use the derived signal for computing the pulse heart rate. Various experiments with different cameras, different illumination condition, and different skin locations were conducted to demonstrate the effectiveness and robustness of the proposed algorithm. Examples computed with normal illumination show the algorithm is comparable with pulse oximeter devices both in accuracy and sensitivity. PMID:24761294

Mental load, heart rate and heart rate variability.

NARCIS (Netherlands)

Blitz, P.S.; Hoogstraten, J.; Mulder, G.

1970-01-01

"Several investigators have shown that diminished sinus arrhythmia can be seen as an indication of increased mental load. The present experiment deals with the influence of different levels of mental load, operationalized as the number of binary choices per minute, on the regularity of the heart

Electrocardiogram application based on heart rate variability ontology and fuzzy markup language

NARCIS (Netherlands)

Wang, M.-H.; Lee, C.-S.; Acampora, G.; Loia, V.; Gacek, A.; Pedrycz, W.

2011-01-01

The electrocardiogram (ECG) signal is adopted extensively as a low-cost diagnostic procedure to provide information concerning the healthy status of the heart. Heart rate variability (HRV) is a physiological phenomenon where the time interval between heart beats varies. It is measured by the

A Robust Dynamic Heart-Rate Detection Algorithm Framework During Intense Physical Activities Using Photoplethysmographic Signals

Directory of Open Access Journals (Sweden)

Jiajia Song

2017-10-01

Full Text Available Dynamic accurate heart-rate (HR estimation using a photoplethysmogram (PPG during intense physical activities is always challenging due to corruption by motion artifacts (MAs. It is difficult to reconstruct a clean signal and extract HR from contaminated PPG. This paper proposes a robust HR-estimation algorithm framework that uses one-channel PPG and tri-axis acceleration data to reconstruct the PPG and calculate the HR based on features of the PPG and spectral analysis. Firstly, the signal is judged by the presence of MAs. Then, the spectral peaks corresponding to acceleration data are filtered from the periodogram of the PPG when MAs exist. Different signal-processing methods are applied based on the amount of remaining PPG spectral peaks. The main MA-removal algorithm (NFEEMD includes the repeated single-notch filter and ensemble empirical mode decomposition. Finally, HR calibration is designed to ensure the accuracy of HR tracking. The NFEEMD algorithm was performed on the 23 datasets from the 2015 IEEE Signal Processing Cup Database. The average estimation errors were 1.12 BPM (12 training datasets, 2.63 BPM (10 testing datasets and 1.87 BPM (all 23 datasets, respectively. The Pearson correlation was 0.992. The experiment results illustrate that the proposed algorithm is not only suitable for HR estimation during continuous activities, like slow running (13 training datasets, but also for intense physical activities with acceleration, like arm exercise (10 testing datasets.

Effects of smoking on heart rate at rest and during exercise, and on heart rate recovery, in young adults.

Science.gov (United States)

Papathanasiou, George; Georgakopoulos, Dimitris; Papageorgiou, Effie; Zerva, Efthimia; Michalis, Lampros; Kalfakakou, Vasiliki; Evangelou, Angelos

2013-01-01

There is an established link between smoking, abnormal heart rate (HR) values, and impaired cardiovascular health in middle-aged or older populations. The purpose of this study was to examine the effects of smoking on resting HR and on HR responses during and after exercise in young adults. A sample of 298 young adults (159 men), aged 20-29 years old, were selected from a large population of health-science students based on health status, body mass index, physical activity, and smoking habit. All subjects underwent a maximal Bruce treadmill test and their HR was recorded during, at peak, and after termination of exercise. Smokers had significantly higher resting HR values than non-smokers. Both female and male smokers showed a significantly slower HR increase during exercise. Female smokers failed to reach their age-predicted maximum HR by 6.0 bpm and males by 3.6 bpm. The actual maximum HR achieved (HRmax) was significantly lower for both female smokers (191.0 bpm vs.198.0 bpm) and male smokers (193.2 bpm vs.199.3 bpm), compared to non-smokers. Heart rate reserve was also significantly lower in female (114.6 bpm vs. 128.1 bpm) and male smokers (120.4 bpm vs. 133.0 bpm). During recovery, the HR decline was significantly attenuated, but only in female smokers. Females had a higher resting HR and showed a higher HR response during sub-maximal exercise compared to males. Smoking was found to affect young smokers' HR, increasing HR at rest, slowing HR increase during exercise and impairing their ability to reach the age-predicted HRmax. In addition, smoking was associated with an attenuated HR decline during recovery, but only in females.

Heart rate variability and heart rate turbulence in patients with polycystic ovary syndrome.

Science.gov (United States)

Özkeçeci, Gülay; Ünlü, Bekir Serdar; Dursun, Hüseyin; Akçi, Önder; Köken, Gülengül; Onrat, Ersel; Avşar, Alaettin

2016-05-01

Cardiac autonomic dysfunction may develop in patients with polycystic ovary syndrome (PCOS). Heart rate variability (HRV) and heart rate turbulence (HRT) are used in assessing cardiac autonomic functions. The goal of this study was to compare the cardiac autonomic functions in patients with PCOS and healthy controls. To our knowledge, this is the first study evaluating cardiac autonomic functions in patients with PCOS with respect to both HRV and HRT. Twenty-three patients with PCOS (mean age 22.8±3.9 years) and 25 healthy female volunteers who were matched for age and body mass index (BMI) (mean age 23.5±6.2 years) were enrolled in this as case-control study. Twenty-four hour ambulatory electrocardiogram recordings of all participants were taken using Pathfinder software. The time domain parameters of HRV and HRT, including turbulence onset (TO) and turbulence slope, were calculated. Diagnosis of PCOS was made with physical and laboratory findings of hirsutism or biochemical hyperandrogenism and chronic anovulation. Diabetes mellitus, other hormon disorders or hormon therapy, pregnancy, atrial fibrilation, obesite, chronic diseases, disorders of the autonomic nervous system, a history of drug use affecting the autonomic nervous system were excluded. There were no significant differences in HRV and HRT parameters between the two groups. Cardiovascular risk factors, such as BMI, blood pressure, fasting blood glucose, and lipid parameters, were also similar. Triangular index measure of HRV was negatively correlated with high density lipoprotein cholesterol levels (r=-0.47, p<0.05), while age and BMI were significantly correlated with TO (r=0.31 and 0.47, respectively; p<0.05 for all). Cardiac autonomic functions were not found to be altered in patients with PCOS in comparison with healthy controls. These results may be explained with the absence of concomitant cardiovascular risk factors with the patients being in the early stage of the disease.

Heart Rate Measures of Flight Test and Evaluation

National Research Council Canada - National Science Library

Bonner, Malcolm A; Wilson, Glenn F

2001-01-01

.... Because flying is a complex task, several measures are required to derive the best evaluation. This article describes the use of heart rate to augment the typical performance and subjective measures used in test and evaluation...

Application of Overall Dynamic Body Acceleration as a Proxy for Estimating the Energy Expenditure of Grazing Farm Animals: Relationship with Heart Rate

Science.gov (United States)

Miwa, Masafumi; Oishi, Kazato; Nakagawa, Yasuhiro; Maeno, Hiromichi; Anzai, Hiroki; Kumagai, Hajime; Okano, Kanji; Tobioka, Hisaya; Hirooka, Hiroyuki

2015-01-01

Estimating the energy expenditure of farm animals at pasture is important for efficient animal management. In recent years, an alternative technique for estimating energy expenditure by measuring body acceleration has been widely performed in wildlife and human studies, but the availability of the technique in farm animals has not yet been examined. In the present study, we tested the potential use of an acceleration index, overall dynamic body acceleration (ODBA), as a new proxy for estimating the energy expenditure of grazing farm animals (cattle, goats and sheep) at pasture with the simultaneous evaluation of a conventional proxy, heart rate. Body accelerations in three axes and heart rate for cows (n = 8, two breeds), goats (n = 6) and sheep (n = 5) were recorded, and the effect of ODBA calculated from the body accelerations on heart rate was analyzed. In addition, the effects of the two other activity indices, the number of steps and vectorial dynamic body acceleration (VeDBA), on heart rate were also investigated. The results of the comparison among three activity indices indicated that ODBA was the best predictor for heart rate. Although the relationship between ODBA and heart rate was different between the groups of species and breeds and between individuals (Panimals, and the results indicated that ODBA is a good proxy for estimating the energy expenditure of grazing farm animals across species and breeds. The utility and simplicity of the procedure with acceleration loggers could make the accelerometry technique a worthwhile option in field research and commercial farm use. PMID:26030931

Features of the heart rate variability in the perioperative period after adenotomy in children

Directory of Open Access Journals (Sweden)

Михайло Борисович Пушкар

2015-03-01

Full Text Available Aim. Study course of perioperative period after adenotomy in children in different ways of general anesthesia by examining indicators of heart rate variability and efficacy of postoperative analgesia.Materials and methods. To study included 70 children aged from 6 to 8 years, which was held adenotomy. Patients were divided into 3 groups: group I (n = 28 - operated under conditions of intravenous anesthesia based on propofol combined with fentanyl; group II (n=23 – operated under conditions of inhalation anesthesia by sevoflurane in combination with fentanyl and analginum; group III (n=19 – operated under conditions of intravenous anesthesia based on thiopental sodium combined with fentanyl. Differences were considered significant at p <0.05 using Student t-test.Results. Indicators of heart rate variability indicated that in the extubation stage in all groups of patients revealed high activity of the sympathetic tone with the trend of decline in the morning after surgery. Statistically higher activity of the sympathetic part of the autonomic nervous system was in patients of group III - 1 hour after surgery compared with patients groups I and II (p <0,001 and p <0,01, respectively. After 1 hour after surgery on the scales "Faces" and "Oucher" scores indicated that the child "a little hurt" in all groups of patients In the dynamics of observation in all groups tended to reduce the intensity of pain. An interpretation of scores on the FLACC scale indicated that patients in both groups felt comfortable.Conclusions. It was found that in patients in all groups there are changes in the nervous regulation of heart rate variability, characterized by increased activity of the sympathetic division of the autonomic nervous system. Postoperative anesthesia by 10 mg / kg ibuprofen provides effective analgesia

Precompetitive assessment of heart rate variability in elite female athletes during play offs.

Science.gov (United States)

D'Ascenzi, Flavio; Alvino, Federico; Natali, Benedetta M; Cameli, Matteo; Palmitesta, Paola; Boschetti, Giampaolo; Bonifazi, Marco; Mondillo, Sergio

2014-05-01

Heart rate variability (HRV) has been rarely applied in elite athletes prior to competition. The aim of this study was to examine the changes in HRV in elite female volleyball players before a stressful match during play offs and to evaluate the impact on sport-specific performance. A short-term resting HRV analysis was applied right after the night sleep in ten female athletes 1 and 2 days prior to the match and the day of the competition. Approaching the decisive match, RR interval, resting heart rate (HR), pNN50, rMSDD and SD1 did not significantly vary. SD2 significantly increased in comparison with first-day measurement (Psports exhibit a slight change in HRV prior to a decisive competition, without a pronounced variation of the autonomic nervous system activity. A day-to-day HRV measurement could be a useful tool to evaluate the impact of a competition on the autonomic nervous system in athletes, also considering the relationship between sympathetic activity and athletic performance. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Office and 24-hour heart rate and target organ damage in hypertensive patients

Directory of Open Access Journals (Sweden)

García-García Ángel

2012-03-01

Full Text Available Abstract Background We investigated the association between heart rate and its variability with the parameters that assess vascular, renal and cardiac target organ damage. Methods A cross-sectional study was performed including a consecutive sample of 360 hypertensive patients without heart rate lowering drugs (aged 56 ± 11 years, 64.2% male. Heart rate (HR and its standard deviation (HRV in clinical and 24-hour ambulatory monitoring were evaluated. Renal damage was assessed by glomerular filtration rate and albumin/creatinine ratio; vascular damage by carotid intima-media thickness and ankle/brachial index; and cardiac damage by the Cornell voltage-duration product and left ventricular mass index. Results There was a positive correlation between ambulatory, but not clinical, heart rate and its standard deviation with glomerular filtration rate, and a negative correlation with carotid intima-media thickness, and night/day ratio of systolic and diastolic blood pressure. There was no correlation with albumin/creatinine ratio, ankle/brachial index, Cornell voltage-duration product or left ventricular mass index. In the multiple linear regression analysis, after adjusting for age, the association of glomerular filtration rate and intima-media thickness with ambulatory heart rate and its standard deviation was lost. According to the logistic regression analysis, the predictors of any target organ damage were age (OR = 1.034 and 1.033 and night/day systolic blood pressure ratio (OR = 1.425 and 1.512. Neither 24 HR nor 24 HRV reached statistical significance. Conclusions High ambulatory heart rate and its variability, but not clinical HR, are associated with decreased carotid intima-media thickness and a higher glomerular filtration rate, although this is lost after adjusting for age. Trial Registration ClinicalTrials.gov: NCT01325064

Effect of Heart rate on Basketball Three-Point Shot Accuracy

Directory of Open Access Journals (Sweden)

Luca P. Ardigò

2018-02-01

Full Text Available The three-point shot (3S is a fundamental basketball skill used frequently during a game, and is often a main determinant of the final result. The aim of the study was to investigate the effect of different metabolic conditions, in terms of heart rates, on 3S accuracy (3S% in 24 male (Under 17 basketball players (age 16.3 ± 0.6 yrs. 3S performance was specifically investigated at different heart rates. All sessions consisted of 10 consecutive 3Ss from five different significant field spots just beyond the FIBA three-point line, i.e., about 7 m from the basket (two counter-clockwise “laps” at different heart rates: rest (0HR, after warm-up (50%HRMAX [50HR], and heart rate corresponding to 80% of its maximum value (80%HRMAX [80HR]. We found that 50HR does not significantly decrease 3S% (−15%, P = 0.255, while 80HR significantly does when compared to 0HR (−28%, P = 0.007. Given that 50HR does not decrease 3S% compared to 0HR, we believe that no preliminary warm-up is needed before entering a game in order to specifically achieve a high 3S%. Furthermore, 3S training should be performed in conditions of moderate-to-high fatigued state so that a high 3S% can be maintained during game-play.

Heart rate variability during pre-competition and competition periods in volleyball players

OpenAIRE

Podstawski Robert; Boraczyński Michał; Nowosielska-Swadźba Danuta; Zwolińska Danuta

2014-01-01

Study aim: Regular exercise training is thought to modify cardiac autonomic control. One of the body’s responses to training stimuli is heart rate variability (HRV). The use of HRV in the management of sport training is a common practice. The objective of the present study was to assess the impact of the physical activity level on HRV of 1st league national volleyball players prior to and during the competition period.

Heart rate variability during pre-competition and competition periods in volleyball players

Directory of Open Access Journals (Sweden)

Podstawski Robert

2014-01-01

Full Text Available Study aim: Regular exercise training is thought to modify cardiac autonomic control. One of the body’s responses to training stimuli is heart rate variability (HRV. The use of HRV in the management of sport training is a common practice. The objective of the present study was to assess the impact of the physical activity level on HRV of 1st league national volleyball players prior to and during the competition period.

The Effect of the Arg389Gly Beta-1 Adrenoceptor Polymorphism on Plasma Renin Activity and Heart Rate and the Genotype-Dependent Response to Metoprolol Treatment

DEFF Research Database (Denmark)

Petersen, Morten; Andersen, Jon T; Jimenez-Solem, Espen

2012-01-01

A gene-drug interaction has been indicated between beta-1 selective beta-blockers and the Arg389Gly polymorphism (rs1801253) in the adrenergic beta-1 receptor gene (ADRB1). We studied the effect of the ADRB1 Arg389Gly polymorphism on plasma renin activity (PRA) and heart rate (HR) and the genotype...

Dynamics of heart rate variability analysed through nonlinear and linear dynamics is already impaired in young type 1 diabetic subjects.

Science.gov (United States)

Souza, Naiara M; Giacon, Thais R; Pacagnelli, Francis L; Barbosa, Marianne P C R; Valenti, Vitor E; Vanderlei, Luiz C M

2016-10-01

Autonomic diabetic neuropathy is one of the most common complications of type 1 diabetes mellitus, and studies using heart rate variability to investigate these individuals have shown inconclusive results regarding autonomic nervous system activation. Aims To investigate the dynamics of heart rate in young subjects with type 1 diabetes mellitus through nonlinear and linear methods of heart rate variability. We evaluated 20 subjects with type 1 diabetes mellitus and 23 healthy control subjects. We obtained the following nonlinear indices from the recurrence plot: recurrence rate (REC), determinism (DET), and Shanon entropy (ES), and we analysed indices in the frequency (LF and HF in ms2 and normalised units - nu - and LF/HF ratio) and time domains (SDNN and RMSSD), through analysis of 1000 R-R intervals, captured by a heart rate monitor. There were reduced values (p<0.05) for individuals with type 1 diabetes mellitus compared with healthy subjects in the following indices: DET, REC, ES, RMSSD, SDNN, LF (ms2), and HF (ms2). In relation to the recurrence plot, subjects with type 1 diabetes mellitus demonstrated lower recurrence and greater variation in their plot, inter-group and intra-group, respectively. Young subjects with type 1 diabetes mellitus have autonomic nervous system behaviour that tends to randomness compared with healthy young subjects. Moreover, this behaviour is related to reduced sympathetic and parasympathetic activity of the autonomic nervous system.

The role of physical activity and heart rate variability for the control of work related stress.

Science.gov (United States)

Tonello, Laís; Rodrigues, Fábio B; Souza, Jeniffer W S; Campbell, Carmen S G; Leicht, Anthony S; Boullosa, Daniel A

2014-01-01

Physical activity (PA) and exercise are often used as tools to reduce stress and therefore the risk for developing cardiovascular diseases (CVD). Meanwhile, heart rate variability (HRV) has been utilized to assess both stress and PA or exercise influences. The objective of the present review was to examine the current literature in regards to workplace stress, PA/exercise and HRV to encourage further studies. We considered original articles from known databases (PubMed, ISI Web of Knowledge) over the last 10 years that examined these important factors. A total of seven studies were identified with workplace stress strongly associated with reduced HRV in workers. Longitudinal workplace PA interventions may provide a means to improve worker stress levels and potentially cardiovascular risk with mechanisms still to be clarified. Future studies are recommended to identify the impact of PA, exercise, and fitness on stress levels and HRV in workers and their subsequent influence on cardiovascular health.

The role of physical activity and heart rate variability for the control of work related stress

Directory of Open Access Journals (Sweden)

Laís eTonello

2014-02-01

Full Text Available Physical activity (PA and exercise are often used as tools to reduce stress and therefore the risk for developing cardiovascular diseases. Meanwhile, heart rate variability (HRV has been utilised to assess both stress and PA or exercise influences. The objective of the present mini review was to examine the current literature in regards to workplace stress, PA/exercise and HRV to encourage further studies. We considered original articles from known databases (PubMed, ISI Web of Knowledge over the last 10 years that examined these important factors. A total of 7 studies were identified with workplace stress strongly associated with reduced HRV in workers. Longitudinal workplace PA interventions may provide a means to improve worker stress levels and potentially cardiovascular risk with mechanisms still to be clarified. Future studies are recommended to identify the impact of PA, exercise and fitness on stress levels and HRV in workers and their subsequent influence on cardiovascular health.

High-Impact Aerobic and Zumba Fitness on Increasing VO2MAX, Heart Rate Recovery and Skinfold Thickness

Science.gov (United States)

Suminar, T. J.; Kusnanik, N. W.; Wiriawan, O.

2018-01-01

Purpose of this study is to determine the significant effect of high-impact aerobics exercise, and Zumba fitness on increasing VO2Max, decreasing of heart rate recovery, and decreasing of skinfold thickness. A sample of this study is 30 members aerobics of student activity unit. Type of this study was quantitative by using a quasi-experimental design method. The design of this study used Matching-Only Design. Data were Analyzed by using the t test (paired t-test). The samples divided into three groups consisted of experimental group I, experimental group II, and control group. They were given a treatment for 8 weeks or 24 meeting. For the data, retrieval is done by MFT test, heart rate recovery test, and skinfold thickness test. Furthermore, the result was analyzed by using SPSS 21 series. In conclusion, significant effect of high-impact aerobics and Zumba fitness on increasing VO2Max, heart rate recovery, skinfold thickness.

Cardiovascular Reactivity and Heart Rate Variability in Panic Disorder

National Research Council Canada - National Science Library

Santiago, Helen T

1999-01-01

.... Because previous studies of cardiovascular reactivity and heart rate variability have been inconclusive, these factors were re-examined in panickers and controls during physiological challenge...

The effect of orthostatic stress on multiscale entropy of heart rate and blood pressure

International Nuclear Information System (INIS)

Turianikova, Zuzana; Javorka, Kamil; Calkovska, Andrea; Javorka, Michal; Baumert, Mathias

2011-01-01

Cardiovascular control acts over multiple time scales, which introduces a significant amount of complexity to heart rate and blood pressure time series. Multiscale entropy (MSE) analysis has been developed to quantify the complexity of a time series over multiple time scales. In previous studies, MSE analyses identified impaired cardiovascular control and increased cardiovascular risk in various pathological conditions. Despite the increasing acceptance of the MSE technique in clinical research, information underpinning the involvement of the autonomic nervous system in the MSE of heart rate and blood pressure is lacking. The objective of this study is to investigate the effect of orthostatic challenge on the MSE of heart rate and blood pressure variability (HRV, BPV) and the correlation between MSE (complexity measures) and traditional linear (time and frequency domain) measures. MSE analysis of HRV and BPV was performed in 28 healthy young subjects on 1000 consecutive heart beats in the supine and standing positions. Sample entropy values were assessed on scales of 1–10. We found that MSE of heart rate and blood pressure signals is sensitive to changes in autonomic balance caused by postural change from the supine to the standing position. The effect of orthostatic challenge on heart rate and blood pressure complexity depended on the time scale under investigation. Entropy values did not correlate with the mean values of heart rate and blood pressure and showed only weak correlations with linear HRV and BPV measures. In conclusion, the MSE analysis of heart rate and blood pressure provides a sensitive tool to detect changes in autonomic balance as induced by postural change

Heart Disease Death Rates Among Blacks and Whites Aged ≥35 Years - United States, 1968-2015.

Science.gov (United States)

Van Dyke, Miriam; Greer, Sophia; Odom, Erika; Schieb, Linda; Vaughan, Adam; Kramer, Michael; Casper, Michele

2018-03-30

Heart disease is the leading cause of death in the United States. In 2015, heart disease accounted for approximately 630,000 deaths, representing one in four deaths in the United States. Although heart disease death rates decreased 68% for the total population from 1968 to 2015, marked disparities in decreases exist by race and state. 1968-2015. The National Vital Statistics System (NVSS) data on deaths in the United States were abstracted for heart disease using diagnosis codes from the eighth, ninth, and tenth revisions of the International Classification of Diseases (ICD-8, ICD-9, and ICD-10) for 1968-2015. Population estimates were obtained from NVSS files. National and state-specific heart disease death rates for the total population and by race for adults aged ≥35 years were calculated for 1968-2015. National and state-specific black-white heart disease mortality ratios also were calculated. Death rates were age standardized to the 2000 U.S. standard population. Joinpoint regression was used to perform time trend analyses. From 1968 to 2015, heart disease death rates decreased for the total U.S. population among adults aged ≥35 years, from 1,034.5 to 327.2 per 100,000 population, respectively, with variations in the magnitude of decreases by race and state. Rates decreased for the total population an average of 2.4% per year, with greater average decreases among whites (2.4% per year) than blacks (2.2% per year). At the national level, heart disease death rates for blacks and whites were similar at the start of the study period (1968) but began to diverge in the late 1970s, when rates for blacks plateaued while rates for whites continued to decrease. Heart disease death rates among blacks remained higher than among whites for the remainder of the study period. Nationwide, the black-white ratio of heart disease death rates increased from 1.04 in 1968 to 1.21 in 2015, with large increases occurring during the 1970s and 1980s followed by small but steady

Effect of Heart rate on Basketball Three-Point Shot Accuracy

OpenAIRE

Luca P. Ardigò; Goran Kuvacic; Antonio D. Iacono; Giacomo Dascanio; Johnny Padulo; Johnny Padulo

2018-01-01

The three-point shot (3S) is a fundamental basketball skill used frequently during a game, and is often a main determinant of the final result. The aim of the study was to investigate the effect of different metabolic conditions, in terms of heart rates, on 3S accuracy (3S%) in 24 male (Under 17) basketball players (age 16.3 ± 0.6 yrs). 3S performance was specifically investigated at different heart rates. All sessions consisted of 10 consecutive 3Ss from five different significant field spot...

[ATP-synthetase activity, respiration and cytochromes of rat heart mitochondria in aging and hyperthyroidism].

Science.gov (United States)

Lemeshko, V V; Kaliman, P A; Belostotskaia, L I; Uchitel', A A

1982-04-01

The ATP-synthetase activity, the rate of oxygen uptake under different metabolic conditions, the tightness of coupling of respiration to oxidative phosphorylation and the cytochrome contents in heart mitochondria of rats from different age groups were studied under normal conditions and in hyperthyroidism. It was found that heart mitochondria of aged animals did not practically differ in terms of their functional activity from those of the young animals. Administration of thyroxin to the animals from all age groups produced no significant effects on the state of mitochondria, increasing the rate of ATP synthesis on alpha-glycerophosphate, which was especially well-pronounced in aged animals, and the cytochrome content in 1-month-old rats.

Spectral analysis of time series of events: effect of respiration on heart rate in neonates

International Nuclear Information System (INIS)

Van Drongelen, Wim; Williams, Amber L; Lasky, Robert E

2009-01-01

Certain types of biomedical processes such as the heart rate generator can be considered as signals that are sampled by the occurring events, i.e. QRS complexes. This sampling property generates problems for the evaluation of spectral parameters of such signals. First, the irregular occurrence of heart beats creates an unevenly sampled data set which must either be pre-processed (e.g. by using trace binning or interpolation) prior to spectral analysis, or analyzed with specialized methods (e.g. Lomb's algorithm). Second, the average occurrence of events determines the Nyquist limit for the sampled time series. Here we evaluate different types of spectral analysis of recordings of neonatal heart rate. Coupling between respiration and heart rate and the detection of heart rate itself are emphasized. We examine both standard and data adaptive frequency bands of heart rate signals generated by models of coupled oscillators and recorded data sets from neonates. We find that an important spectral artifact occurs due to a mirror effect around the Nyquist limit of half the average heart rate. Further we conclude that the presence of respiratory coupling can only be detected under low noise conditions and if a data-adaptive respiratory band is used

Clinical Feasibility of Continuously Monitored Data for Heart Rate, Physical Activity, and Sleeping by Wearable Activity Trackers in Patients with Thyrotoxicosis: Protocol for a Prospective Longitudinal Observational Study

Science.gov (United States)

Lee, Jie-Eun; Lee, Dong Hwa; Oh, Tae Jung; Kim, Kyoung Min; Choi, Sung Hee; Lim, Soo; Park, Young Joo; Park, Do Joon; Jang, Hak Chul

2018-01-01

Background Thyrotoxicosis is a common disease caused by an excess of thyroid hormones. The prevalence of thyrotoxicosis about 2% and 70-90% of thyrotoxicosis cases are caused by Graves' disease, an autoimmune disease, which has a high recurrence rate when treated with antithyroid drugs such as methimazole or propylthiouracil. The clinical symptoms and signs of thyrotoxicosis include palpitation, weight loss, restlessness, and difficulty sleeping. Although these clinical changes in thyrotoxicosis can be detected by currently available wearable activity trackers, there have been few trials of the clinical application of wearable devices in patients with thyrotoxicosis. Objective The aim of this study is to investigate the clinical applicability of wearable device-generated data to the management of thyrotoxicosis. We are analyzing continuously monitored data for heart rate, physical activity, and sleep in patients with thyrotoxicosis during their clinical course after treatment. Methods Thirty thyrotoxic patients and 10 control subjects were enrolled in this study at Seoul National University Bundang Hospital. Heart rate, physical activity, and sleep are being monitored using a Fitbit Charge HR or Fitbit Charge 2. Clinical data including anthropometric measures, thyroid function test, and hyperthyroidism symptom scale are recorded. Results Study enrollment began in December 2016, and the intervention and follow-up phases are ongoing. The results of the data analysis are expected to be available by September 2017. Conclusions This study will provide a foundational feasibility trial of the clinical applications of biosignal measurements to the differential diagnosis, prediction of clinical course, early detection of recurrence, and treatment in patients with thyrotoxicosis. Trial Registration ClinicalTrials.gov NCT03009357; https://clinicaltrials.gov/ct2/show/NCT03009357 (Archived by WebCite at http://www.webcitation.org/6wh4MWPm2) PMID:29467121

Heart rate-based lactate minimum test: a reproducible method.

NARCIS (Netherlands)

Strupler, M.; Muller, G.; Perret, C.

2009-01-01

OBJECTIVE: To find the individual intensity for aerobic endurance training, the lactate minimum test (LMT) seems to be a promising method. LMTs described in the literature consist of speed or work rate-based protocols, but for training prescription in daily practice mostly heart rate is used. The

Heart rate variability analysis in healthy subjects, patients suffering from congestive heart failure and heart transplanted patients

Directory of Open Access Journals (Sweden)

Argentina Leite

2013-12-01

Full Text Available This study aimed to find parameters to characterize heart rate variability (HRV and discriminate healthy subjects and patients with heart diseases. The parameters used for discrimination characterize the different components of HRV memory (short and long and are extracted from HRV recordings using parametric as well as non parametric methods. Thus, the parameters are: spectral components at low frequencies (LH and high frequencies (HF which are associated with the short memory of HRV and the long memory parameter (d obtained from autoregressive fractionally integrated moving average (ARFIMA models. In the non parametric context, short memory (α1 and long memory (α2 parameters are obtained from detrended fluctuation analysis (DFA. The sample used in this study contains 24-hour Holter HRV recordings of 30 subjects: 10 healthy individuals, 10 patients suffering from congestive heart failure and 10 heart transplanted patients from the Noltisalis database. It was found that short memory parameters present higher values for the healthy individuals whereas long memory parameters present higher values for the diseased individuals. Moreover, there is evidence that ARFIMA modeling allows the discrimination between the 3 groups under study, being advantageous over DFA.

Effect of atrioventricular conduction on heart rate variability

KAUST Repository

Ahmad, Talha Jamal; Ali, Hussnain; Majeed, S. M Imran; Khan, Shoab A.

2011-01-01

This paper discusses the effect of atrioventricular conduction time (AVCT) on the short-term Heart Rate Variability (HRV) by computing HRV parameters using intervals between the onsets of successive P waves (PP time series) for three groups: normal

Heart Rate Variability during Social Interactions in Children with and without Psychopathology: A Meta-Analysis

Science.gov (United States)

Shahrestani, Sara; Stewart, Elizabeth M.; Quintana, Daniel S.; Hickie, Ian B.; Guastella, Adam J.

2014-01-01

Background: The inability to regulate autonomic activity during social interactions is believed to contribute to social and emotional dysregulation in children. Research has employed heart rate variability (HRV) during both socially engaging and socially disengaging dyadic tasks between children and adults to assess this. Methods: We conducted a…

Variation in heart rate influences the assessment of transient ischemic dilation in myocardial perfusion scintigraphy

International Nuclear Information System (INIS)

Leslie, William D; Levin, Daniel P; Demeter, Sandor J

2007-01-01

Transient arrhythmias can affect transient ischemic dilation (TID) ratios. This study was initiated to evaluate the frequency and effect of normal heart rate change on TID measures in routine clinical practice. Consecutive patients undergoing stress/rest sestamibi gated myocardial perfusion scintigraphy were studied (N = 407). Heart rate at the time of stress and rest imaging were recorded. TID ratios were analyzed in relation to absolute change in heart rate (stress minus rest) for subjects with normal perfusion and systolic function (Group 1, N = 169) and those with abnormalities in perfusion and/or function (Group 2, N = 238). In Group 1, mean TID ratio was inversely correlated with the change in heart rate (r = -0.47, P < 0.0001). For every increase of 10 BPM in heart rate change, the TID ratio decreased by approximately 0.06 (95% confidence interval 0.04–0.07). In Group 2, multiple linear regression demonstrated that the change in heart rate (beta = -0.25, P < 0.0001) and the summed difference score (beta = 0.36, P < 0.0001) were independent predictors of the TID ratio. Normal variation in heart rate between the stress and rest components of myocardial perfusion scans is common and can influence TID ratios in patients with normal and abnormal cardiac scans

Heart rate variability in workers chronically exposed to lead.

Science.gov (United States)

Gajek, Jacek; Zyśko, Dorota; Chlebda, Ewa

2004-07-01

Lead is a strong neurotoxin. The effects of lead on the activity of the autonomic nervous system, assessed by the use of heart rate variability (HRV) analysis, have not yet been established. To assess the effects of occupational chronic lead exposure on the autonomic nervous system activity. The study group consisted of 22 copper foundry workers (mean age 41.8+/-8.7 years) who had elevated parameters of lead overload and were admitted to the hospital for chelate therapy. The control group consisted of 13 age-matched healthy males. Lead concentration was measured with the use of atomic absorption spectrophotometry, and concentration of free protoporphyrins in erythrocytes (FEP) using a fluorometric method. Each patient underwent 24-hour ambulatory ECG monitoring, and standard short-term as well as long-term HRV parameters were obtained. There were no significant differences between patients and controls in HRV parameters. In the control group, HRV parameters correlated with age. In patients, a significant negative correlation between lead concentration and some short-term HRV parameters calculated during the night was found: SDNN (r=-0.48, p<0.05), TP (r=-0.48, p<0.01) and LF (r=-0.48, p<0.01). In patients, a negative correlation between lead concentration and HFnight/HFday index was found (r=-0.47 p<0.01), whereas in controls this correlation was positive (r=0.66 p<0.05). Overall HRV indices are similar in subjects exposed to lead and in healthy controls. A decrease in the physiological elevation of HF values during the night, together with an increase in lead blood concentration and lack of relationship between age and HRV parameters in workers chronically exposed to lead may suggest disturbances of the autonomic system. In subjects not exposed to lead a decrease in heart rate with an increase in FEP concentration was observed.

gHRV: Heart rate variability analysis made easy.

Science.gov (United States)

Rodríguez-Liñares, L; Lado, M J; Vila, X A; Méndez, A J; Cuesta, P

2014-08-01

In this paper, the gHRV software tool is presented. It is a simple, free and portable tool developed in python for analysing heart rate variability. It includes a graphical user interface and it can import files in multiple formats, analyse time intervals in the signal, test statistical significance and export the results. This paper also contains, as an example of use, a clinical analysis performed with the gHRV tool, namely to determine whether the heart rate variability indexes change across different stages of sleep. Results from tests completed by researchers who have tried gHRV are also explained: in general the application was positively valued and results reflect a high level of satisfaction. gHRV is in continuous development and new versions will include suggestions made by testers. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Using a smartphone to measure heart rate changes during relived happiness and anger

NARCIS (Netherlands)

Lakens, D.

2013-01-01

This study demonstrates the feasibility of measuring heart rate differences associated with emotional states such as anger and happiness with a smartphone. Novice experimenters measured higher heart rates during relived anger and happiness (replicating findings in the literature) outside a

Effect of the Torrance Creative Thinking Test on Heart Rate Signal Features

Directory of Open Access Journals (Sweden)

Zakeri S.

2016-02-01

Full Text Available Aims: Showing a meta-cognitive aspect, creativity is related to higher mental processes such as thinking, intelligence, imagination, and information process. There are many studies on the physiological bases of creativity. The aim of this study was to investigate the effects of creative thinking on the heart rate signal. Materials & Methods: In this semi-experimental study, 52 medical engineering, electrical, and control students of Sahand University were studied in 2012. The subjects were selected via accessible sampling method. To assess the level of the students’ creative thinking, Torrance Tests of Creative Thinking (B form; figural was used. Before and during creative thinking test, heart signal in the rest position was recorded by 1000Hz sampling frequency. Data was analyzed using Wilcoxon non-parametric test.   Findings: There was an increase in the mean heart power amplitude during creative thinking than the rest position. However, passing time and conducting the last sessions of the creativity test, it showed a reduction. There was an increase in the heart rate in persons with high creativity than those with low creativity. In addition, based on the test scores, there was a higher creativity level in females and three-lingual persons than males and bi-lingual persons, respectively. There was an increase in the heart rate in females than males (p=0.0398. Nevertheless, there was no significant difference between three-lingual and bilingual persons (p>0.05.    Conclusion: Creative thinking results in an increase in the heart rate in persons with high creativity than persons with low creativity. Therefore, the creativity level can be detected via heart signal. 

Heart rate variability in normal-weight patients with polycystic ovary syndrome

OpenAIRE

Kilit, Celal; Kilit, T?rkan Pa?al?

2017-01-01

Objective: Polycystic ovary syndrome (PCOS) is an endocrine disease closely related to several risk factors of cardiovascular disease. Obese women with PCOS show altered autonomic modulation. The results of studies investigating cardiac autonomic functions of normal-weight women with PCOS are conflicting. The aim of the study was to assess the reactivity of cardiac sympathovagal balance in normal-weight women with PCOS by heart rate variability analysis. Methods: We examined the heart rate va...

Early warnings of heart rate deterioration

OpenAIRE

Almeida, Vânia G.; Nabney, Ian T.

2016-01-01

Hospitals can experience difficulty in detecting and responding to early signs of patient deterioration leading to late intensive care referrals, excess mortality and morbidity, and increased hospital costs. Our study aims to explore potential indicators of physiological deterioration by the analysis of vital-signs. The dataset used comprises heart rate (HR) measurements from MIMIC II waveform database, taken from six patients admitted to the Intensive Care Unit (ICU) and diagnosed with sever...

Endogenous Pain Modulation: Association with Resting Heart Rate Variability and Negative Affectivity.

Science.gov (United States)

Van Den Houte, Maaike; Van Oudenhove, Lukas; Bogaerts, Katleen; Van Diest, Ilse; Van den Bergh, Omer

2017-07-21

Several chronic pain syndromes are characterized by deficient endogenous pain modulation as well as elevated negative affectivity and reduced resting heart rate variability. In order to elucidate the relationships between these characteristics, we investigated whether negative affectivity and heart rate variability are associated with endogenous pain modulation in a healthy population. An offset analgesia paradigm with noxious thermal stimulation calibrated to the individual's pain threshold was used to measure endogenous pain modulation magnitude in 63 healthy individuals. Pain ratings during constant noxious heat stimulation to the arm (15 seconds) were compared with ratings during noxious stimulation comprising a 1 °C rise and return of temperature to the initial level (offset trials, 15 seconds). Offset analgesia was defined as the reduction in pain following the 1 °C decrease relative to pain at the same time point during continuous heat stimulation. Evidence for an offset analgesia effect could only be found when noxious stimulation intensity (and, hence, the individual's pain threshold) was intermediate (46 °C or 47 °C). Offset analgesia magnitude was also moderated by resting heart rate variability: a small but significant offset effect was found in participants with high but not low heart rate variability. Negative affectivity was not related to offset analgesia magnitude. These results indicate that resting heart rate variability (HRV) is related to endogenous pain modulation (EPM) in a healthy population. Future research should focus on clarifying the causal relationship between HRV and EPM and chronic pain by using longitudinal study designs. © 2017 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Incident solar radiation and coronary heart disease mortality rates in Europe

International Nuclear Information System (INIS)

Wong, Alfred

2008-01-01

The reported low mortality rate from coronary heart disease in Portugal, Spain, Italy, Greece, and France, to a lesser extent, has been attributed in numerous nutritional studies to the consumption of a Mediterranean-type diet. There are still many unresolved issues about the direct causal effect of the Mediterranean dietary regime on low incidence of coronary heart disease. An analysis of coronary heart disease mortality rates in Europe from a latitudinal gradient perspective has shown to have a close correlation to incident solar radiation. It is surmised that the resulting increased in situ biosynthesis of Vitamin D 3 could be the critical missing confounder in the analysis of the beneficial health outcome of the Mediterranean diet

Effect of pre operative heart rate on post spinal hypotension in obsteric patients

International Nuclear Information System (INIS)

Khan, S.; Zahoor, M.U.; Zaid, A.Y.; Buland, K.

2010-01-01

The purpose of the study was to determine the association between of preoperative heart rate and post spinal hypotension in women undergoing cesarean section, Two hundred patients undergoing caesarean were included in the study selected on non probability convenience sampling technique, The patients were divided into two groups depending upon their pre operative heart rate. Spinal anesthesia was administered and number of patients developing hypotension was noted. Among 200 patients, who were included in the study; 112 were placed in group A and 88 were placed in group B depending on mean heart rate of 90 beats per minute or less or 91 beats per minute or more respectively. In group A 14 (11.86%) patients developed hypotension where as in group B 28 (31,82%) patients developed hypotension. Pre operative heart rate is significantly associated with post spinal hypotension in obstetric patients undergoing cesarean section. (author)

Design of a heart rate controller for treadmill exercise using a recurrent fuzzy neural network.

Science.gov (United States)

Lu, Chun-Hao; Wang, Wei-Cheng; Tai, Cheng-Chi; Chen, Tien-Chi

2016-05-01

In this study, we developed a computer controlled treadmill system using a recurrent fuzzy neural network heart rate controller (RFNNHRC). Treadmill speeds and inclines were controlled by corresponding control servo motors. The RFNNHRC was used to generate the control signals to automatically control treadmill speed and incline to minimize the user heart rate deviations from a preset profile. The RFNNHRC combines a fuzzy reasoning capability to accommodate uncertain information and an artificial recurrent neural network learning process that corrects for treadmill system nonlinearities and uncertainties. Treadmill speeds and inclines are controlled by the RFNNHRC to achieve minimal heart rate deviation from a pre-set profile using adjustable parameters and an on-line learning algorithm that provides robust performance against parameter variations. The on-line learning algorithm of RFNNHRC was developed and implemented using a dsPIC 30F4011 DSP. Application of the proposed control scheme to heart rate responses of runners resulted in smaller fluctuations than those produced by using proportional integra control, and treadmill speeds and inclines were smoother. The present experiments demonstrate improved heart rate tracking performance with the proposed control scheme. The RFNNHRC scheme with adjustable parameters and an on-line learning algorithm was applied to a computer controlled treadmill system with heart rate control during treadmill exercise. Novel RFNNHRC structure and controller stability analyses were introduced. The RFNNHRC were tuned using a Lyapunov function to ensure system stability. The superior heart rate control with the proposed RFNNHRC scheme was demonstrated with various pre-set heart rates. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Heart rate variability and swimming.

Science.gov (United States)

Koenig, Julian; Jarczok, Marc N; Wasner, Mieke; Hillecke, Thomas K; Thayer, Julian F

2014-10-01

Professionals in the domain of swimming have a strong interest in implementing research methods in evaluating and improving training methods to maximize athletic performance and competitive outcome. Heart rate variability (HRV) has gained attention in research on sport and exercise to assess autonomic nervous system activity underlying physical activity and sports performance. Studies on swimming and HRV are rare. This review aims to summarize the current evidence on the application of HRV in swimming research and draws implications for future research. A systematic search of databases (PubMed via MEDLINE, PSYNDEX and Embase) according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (a) empirical investigation (HRV) in humans (non-clinical); (b) related to swimming; (c) peer-reviewed journal; and (d) English language. The search revealed 194 studies (duplicates removed), of which the abstract was screened for eligibility. Fourteen studies meeting the inclusion criteria were included in the review. Included studies broadly fell into three classes: (1) control group designs to investigate between-subject differences (i.e. swimmers vs. non-swimmers, swimmers vs. other athletes); (2) repeated measures designs on within-subject differences of interventional studies measuring HRV to address different modalities of training or recovery; and (3) other studies, on the agreement of HRV with other measures. The feasibility and possibilities of HRV within this particular field of application are well documented within the existing literature. Future studies, focusing on translational approaches that transfer current evidence in general practice (i.e. training of athletes) are needed.

Changes in heart rate associated with contest outcome in agonistic encounters in lobsters.

Science.gov (United States)

Hernáindez-Falcón, Jesús; Basu, Alo C; Govindasamy, Siddhartan; Kravitz, Edward A

2005-03-01

Agonistic contests between lobsters housed together in a confined space progress through encounters of increasing intensity until a dominance relationship is established. Once this relationship is established, losing animals continually retreat from the advances of winners. These encounters are likely to consume much energy in both winning and losing animals. Therefore, one might expect involvement of many physiological systems before, during and after fights. Here, we report effects of agonistic encounters on cardiac frequency in winning and losing adult lobsters involved in dyadic interactions. The results show that: (i) small but significant increases in heart rate are observed upon chemical detection of a conspecific; (ii) during agonistic interactions, further increases in heart rate are seen; and (iii) ultimate winners exhibit greater increases in heart rate lasting longer periods of time compared to ultimate losers. Heart rate in winners remains elevated for at least 15 min after the contests have ended and animals have been returned to their home tanks. Reduced effects are seen in second and third pairings between familiar opponents. The sustained changes in heart rate that we observe in winning lobsters may result from hormonal modulation of cardiac function related to the change in social status brought about by contest outcome.

Embryos in the fast lane: high-temperature heart rates of turtles decline after hatching.

Directory of Open Access Journals (Sweden)

Wei-Guo Du

Full Text Available In ectotherms such as turtles, the relationship between cardiovascular function and temperature may be subject to different selective pressures in different life-history stages. Because embryos benefit by developing as rapidly as possible, and can "afford" to expend energy to do so (because they have access to the yolk for nutrition, they benefit from rapid heart (and thus, developmental rates. In contrast, hatchlings do not have a guaranteed food supply, and maximal growth rates may not enhance fitness--and so, we might expect a lower heart rate, especially at high temperatures where metabolic costs are greatest. Our data on two species of emydid turtles, Chrysemys picta, and Graptemys pseudogeographica kohnii, support these predictions. Heart rates of embryos and hatchlings were similar at low temperatures, but heart rates at higher temperatures were much greater before than after hatching.

Microsoft Kinect Visual and Depth Sensors for Breathing and Heart Rate Analysis

Directory of Open Access Journals (Sweden)

Aleš Procházka

2016-06-01

Full Text Available This paper is devoted to a new method of using Microsoft (MS Kinect sensors for non-contact monitoring of breathing and heart rate estimation to detect possible medical and neurological disorders. Video sequences of facial features and thorax movements are recorded by MS Kinect image, depth and infrared sensors to enable their time analysis in selected regions of interest. The proposed methodology includes the use of computational methods and functional transforms for data selection, as well as their denoising, spectral analysis and visualization, in order to determine specific biomedical features. The results that were obtained verify the correspondence between the evaluation of the breathing frequency that was obtained from the image and infrared data of the mouth area and from the thorax movement that was recorded by the depth sensor. Spectral analysis of the time evolution of the mouth area video frames was also used for heart rate estimation. Results estimated from the image and infrared data of the mouth area were compared with those obtained by contact measurements by Garmin sensors (www.garmin.com. The study proves that simple image and depth sensors can be used to efficiently record biomedical multidimensional data with sufficient accuracy to detect selected biomedical features using specific methods of computational intelligence. The achieved accuracy for non-contact detection of breathing rate was 0.26% and the accuracy of heart rate estimation was 1.47% for the infrared sensor. The following results show how video frames with depth data can be used to differentiate different kinds of breathing. The proposed method enables us to obtain and analyse data for diagnostic purposes in the home environment or during physical activities, enabling efficient human–machine interaction.

Lack of evidence for low-dimensional chaos in heart rate variability

DEFF Research Database (Denmark)

Kanters, J K; Holstein-Rathlou, N H; Agner, E

1994-01-01

INTRODUCTION: The term chaos is used to describe erratic or apparently random time-dependent behavior in deterministic systems. It has been suggested that the variability observed in the normal heart rate may be due to chaos, but this question has not been settled. METHODS AND RESULTS: Heart rate...... in the experimental data, but the prediction error as a function of the prediction length increased at a slower rate than characteristic of a low-dimensional chaotic system. CONCLUSION: There is no evidence for low-dimensional chaos in the time series of RR intervals from healthy human subjects. However, nonlinear...

Ivabradine, a novel heart rate slower: is it a sword of double blades in patients with idiopathic dilated cardiomyopathy?

Science.gov (United States)

Rayan, Mona; Tawfik, Mazen; Alabd, Ali; Gamal, Amr

2011-08-01

To prospectively assess the safety and efficacy of ivabradine in patients with idiopathic dilated cardiomyopathy. We included 35 patients with idiopathic dilated cardiomyopathy with an ejection fraction (EF) 70 beats/min despite optimal medical therapy, according to the international guidelines in this prospective, non-randomized, single-arm, open-label safety study. Ivabradine was used as an add-on therapy to the maximally tolerated b-blocker in an increasing titrated dose till a target dose of 15 mg/day or resting heart rate of 60 beats/min for 3 months. During follow-up period the safety, patient tolerance and efficacy of this drug were assessed. All patients underwent 12-lead resting electrocardiography and Holter monitoring at inclusion and after 3 months. Statistical analysis was accomplished using paired t-test and Pearson correlation analysis. We found a significant reduction in the resting heart rate by a mean of 25.9 ± 9.4%, without a significant change of blood pressure. There was no prolongation of PR, QTc or QRS durations. Ventricular ectopic activity showed significant reduction (p<0.001). There was a significant correlation between the resting heart rate, NYHA and left ventricular ejection fraction (p<0.001 for both). One patient developed photopsia and decompensation was observed in another patient. Ivabradine is a safe and effective drug in reducing resting heart rate, improving NYHA functional class without undesirable effects on conduction parameters or ectopic activity.

Application of overall dynamic body acceleration as a proxy for estimating the energy expenditure of grazing farm animals: relationship with heart rate.

Science.gov (United States)

Miwa, Masafumi; Oishi, Kazato; Nakagawa, Yasuhiro; Maeno, Hiromichi; Anzai, Hiroki; Kumagai, Hajime; Okano, Kanji; Tobioka, Hisaya; Hirooka, Hiroyuki

2015-01-01

Estimating the energy expenditure of farm animals at pasture is important for efficient animal management. In recent years, an alternative technique for estimating energy expenditure by measuring body acceleration has been widely performed in wildlife and human studies, but the availability of the technique in farm animals has not yet been examined. In the present study, we tested the potential use of an acceleration index, overall dynamic body acceleration (ODBA), as a new proxy for estimating the energy expenditure of grazing farm animals (cattle, goats and sheep) at pasture with the simultaneous evaluation of a conventional proxy, heart rate. Body accelerations in three axes and heart rate for cows (n = 8, two breeds), goats (n = 6) and sheep (n = 5) were recorded, and the effect of ODBA calculated from the body accelerations on heart rate was analyzed. In addition, the effects of the two other activity indices, the number of steps and vectorial dynamic body acceleration (VeDBA), on heart rate were also investigated. The results of the comparison among three activity indices indicated that ODBA was the best predictor for heart rate. Although the relationship between ODBA and heart rate was different between the groups of species and breeds and between individuals (Pheart rate (beats/min) = 147.263∙M-0.141 + 889.640∙M-0.179∙ODBA (g). Combining this equation with the previously reported energy expenditure per heartbeat, we estimated the energy expenditure of the tested animals, and the results indicated that ODBA is a good proxy for estimating the energy expenditure of grazing farm animals across species and breeds. The utility and simplicity of the procedure with acceleration loggers could make the accelerometry technique a worthwhile option in field research and commercial farm use.

General anesthesia suppresses normal heart rate variability in humans

Science.gov (United States)

Matchett, Gerald; Wood, Philip

2014-06-01

The human heart normally exhibits robust beat-to-beat heart rate variability (HRV). The loss of this variability is associated with pathology, including disease states such as congestive heart failure (CHF). The effect of general anesthesia on intrinsic HRV is unknown. In this prospective, observational study we enrolled 100 human subjects having elective major surgical procedures under general anesthesia. We recorded continuous heart rate data via continuous electrocardiogram before, during, and after anesthesia, and we assessed HRV of the R-R intervals. We assessed HRV using several common metrics including Detrended Fluctuation Analysis (DFA), Multifractal Analysis, and Multiscale Entropy Analysis. Each of these analyses was done in each of the four clinical phases for each study subject over the course of 24 h: Before anesthesia, during anesthesia, early recovery, and late recovery. On average, we observed a loss of variability on the aforementioned metrics that appeared to correspond to the state of general anesthesia. Following the conclusion of anesthesia, most study subjects appeared to regain their normal HRV, although this did not occur immediately. The resumption of normal HRV was especially delayed on DFA. Qualitatively, the reduction in HRV under anesthesia appears similar to the reduction in HRV observed in CHF. These observations will need to be validated in future studies, and the broader clinical implications of these observations, if any, are unknown.

Analyses of Heart Rate, Respiration and Cardiorespiratory Coupling in Patients with Schizophrenia

Directory of Open Access Journals (Sweden)

Steffen Schulz

2015-01-01

Full Text Available Schizophrenia is a severe mental disorder associated with a significantly increased cardiovascular mortality rate. However, the underlying mechanisms leading to this cardiovascular disease (CVD are not fully known. Therefore, the objective of this study was to characterize the cardiorespiratory influence by investigating heart rate, respiration and the causal strength and direction of cardiorespiratory coupling (CRC, based mainly on entropy measures. We investigated 23 non-medicated patients with schizophrenia (SZ, comparing them to 23 age- and gender-matched healthy controls (CO. A significantly reduced complexity was found for the heart rate and a significantly increased complexity in respiration and CRC in SZ patients when compared to corresponding measurements from CO (p < 0.001. CRC analyses revealed a clear coupling, with a driver-responder relationship from respiration to heart rate in SZ patients. Moreover, a slight driver-responder relationship from heart rate to respiration could be recognized. These findings lead to the assumption that SZ should be considered to be a high-risk group for CVD. We hypothesize that the varying cardiorespiratory regulation contributes to the increased risk for cardiac mortality. Therefore, regular monitoring of the cardiorespiratory status of SZ is suggested to identify autonomic regulation impairment at an early stage—to develop timely and effective treatment and intervention strategies.

Nonlinear analysis of heart rate variability in patients with eating disorders

NARCIS (Netherlands)

Vigo, Daniel E.; Castro, Mariana N.; Dorpinghaus, Andrea; Weidema, Hylke; Cardinali, Daniel P.; Siri, Leonardo Nicola; Rovira, Bernardo; Fahrer, Rodolfo D.; Nogues, Martin; Leiguarda, Ramon C.; Guinjoan, Salvador M.

2008-01-01

Patients with anorexia nervosa or bulimia nervosa often have signs of autonomic dysfunction potentially deleterious to the heart. The aim of this study was to ascertain the nonlinear properties of heart rate variability in patients with eating disorders. A group of 33 women with eating disorders (14

Glutamate transporter type 3 knockout leads to decreased heart rate possibly via parasympathetic mechanism

OpenAIRE

Deng, Jiao; Li, Jiejie; Li, Liaoliao; Feng, Chenzhuo; Xiong, Lize; Zuo, Zhiyi

2013-01-01

Parasympathetic tone is a dominant neural regulator for basal heart rate. Glutamate transporters (EAAT) via their glutamate uptake functions regulate glutamate neurotransmission in the central nervous system. We showed that EAAT type 3 (EAAT3) knockout mice had a slower heart rate than wild-type mice when they were anesthetized. We design this study to determine whether non-anesthetized EAAT3 knockout mice have a slower heart rate and, if so, what may be the mechanism for this effect. Young a...

Comparison of carbon dioxide and argon euthanasia: effects on behavior, heart rate, and respiratory lesions in rats.

Science.gov (United States)

Burkholder, Tanya H; Niel, Lee; Weed, James L; Brinster, Lauren R; Bacher, John D; Foltz, Charmaine J

2010-07-01

In this study we compared rat (n = 16) responses to euthanasia with either gradual-fill CO(2) or rapid induction argon gas by evaluating the animals' heart rate via radiotelemetry, behavior, and vocalizations. We also evaluated the histologic effects of the gases. Rats were placed in an open test chamber 24 h before the start of the experiment. During baseline tests, rats were exposed to oxygen to evaluate the effects of the noise and movement of gas entering the chamber; 1 wk later, rats were euthanized by gas displacement with either 10%/min CO(2) or 50%/min argon gas. Rats tended to have higher heart rats and were more active during the baseline test, but these parameters were normal before the euthanasia experiment, suggesting that the rats had acclimated to the equipment. Heart rate, behavior, and ultrasonic vocalizations were recorded for 2 min after gas introduction in both groups. All rats appeared conscious throughout the test interval. The heart rates of rats exposed to argon did not change, whereas those of rats exposed to CO(2) declined significantly. Unlike those exposed to CO(2), rats euthanized with argon gas gasped and demonstrated seizure-like activity. There were no differences in the pulmonary lesions resulting from death by either gas. Our results suggest that argon as a sole euthanasia agent is aversive to rats. CO(2) using a 10%/min displacement may be less aversive than more rapid displacements. Future research investigating methods of euthanasia should allow sufficient time for the rats to acclimate to the test apparatus.

Fetal heart rate patterns in neonatal hypoxic-ischemic encephalopathy: relationship with early cerebral activity and neurodevelopmental outcome.

LENUS (Irish Health Repository)

Murray, Deirdre M

2009-09-01

Despite widespread use of fetal heart rate monitoring, the timing of injury in hypoxic-ischemic encephalopathy (HIE) remains unclear. Our aim was to examine fetal heart rate patterns during labor in infants with clinical and electroencephalographic (EEG) evidence of HIE and to relate these findings to neurodevelopmental outcome. Timing of onset of pathological cardiotocographs (CTGs) was determined in each case by two blinded reviewers and related to EEG grade at birth and neurological outcome at 24 months. CTGs were available in 35 infants with HIE (17 mild, 12 moderate, 6 severe on EEG). Admission CTGs were normal in 24\\/35 (69%), suspicious in 8\\/35 (23%), and pathological in 3\\/35 (8%). All CTGs developed nonreassuring features prior to delivery. Three patterns of fetal heart rate abnormalities were seen: group 1, abnormal CTGs on admission in 11\\/35 (31%); group 2, normal CTGs on admission with gradual deterioration to pathological in 20\\/35 cases (57%); and group 3, normal CTGs on admission with acute sentinel events in 4\\/35 (11.5%). The median (interquartile range) duration between the development of pathological CTGs and delivery was 145 (81, 221) minutes in group 2 and 22 (12, 28) minutes in group 3. There was no correlation between duration of pathological CTG trace and grade of encephalopathy (R = 0.09, P = 0.63) or neurological outcome (P = 0.75). However, the grade of encephalopathy was significantly worse in group 3 (P = 0.001), with a trend to worse outcomes. The majority of infants with HIE have normal CTG traces on admission but develop pathological CTG patterns within hours of delivery. More severe encephalopathy was associated with normal admission CTG and acute sentinel events shortly before delivery.

Fetal heart rate patterns in neonatal hypoxic-ischemic encephalopathy: relationship with early cerebral activity and neurodevelopmental outcome.

LENUS (Irish Health Repository)

Murray, Deirdre M

2012-01-31

Despite widespread use of fetal heart rate monitoring, the timing of injury in hypoxic-ischemic encephalopathy (HIE) remains unclear. Our aim was to examine fetal heart rate patterns during labor in infants with clinical and electroencephalographic (EEG) evidence of HIE and to relate these findings to neurodevelopmental outcome. Timing of onset of pathological cardiotocographs (CTGs) was determined in each case by two blinded reviewers and related to EEG grade at birth and neurological outcome at 24 months. CTGs were available in 35 infants with HIE (17 mild, 12 moderate, 6 severe on EEG). Admission CTGs were normal in 24\\/35 (69%), suspicious in 8\\/35 (23%), and pathological in 3\\/35 (8%). All CTGs developed nonreassuring features prior to delivery. Three patterns of fetal heart rate abnormalities were seen: group 1, abnormal CTGs on admission in 11\\/35 (31%); group 2, normal CTGs on admission with gradual deterioration to pathological in 20\\/35 cases (57%); and group 3, normal CTGs on admission with acute sentinel events in 4\\/35 (11.5%). The median (interquartile range) duration between the development of pathological CTGs and delivery was 145 (81, 221) minutes in group 2 and 22 (12, 28) minutes in group 3. There was no correlation between duration of pathological CTG trace and grade of encephalopathy (R = 0.09, P = 0.63) or neurological outcome (P = 0.75). However, the grade of encephalopathy was significantly worse in group 3 (P = 0.001), with a trend to worse outcomes. The majority of infants with HIE have normal CTG traces on admission but develop pathological CTG patterns within hours of delivery. More severe encephalopathy was associated with normal admission CTG and acute sentinel events shortly before delivery.

Energy expenditure estimation in beta-blocker-medicated cardiac patients by combining heart rate and body movement data

NARCIS (Netherlands)

Kraal, Jos J.; Sartor, Francesco; Papini, Gabriele; Stut, Wim; Peek, Niels; Kemps, Hareld Mc; Bonomi, Alberto G.

2016-01-01

Accurate assessment of energy expenditure provides an opportunity to monitor physical activity during cardiac rehabilitation. However, the available assessment methods, based on the combination of heart rate (HR) and body movement data, are not applicable for patients using beta-blocker medication.

Combinatorial effect of nicotine and black tea on heart rate variability: Useful or harmful?

Science.gov (United States)

Joukar, S; Sheibani, M

2017-06-01

The effect of nicotine on heart rate variability (HRV) is controversial. Autonomic nervous system is the main regulator of heart rhythm, and heart rate variability is an appropriate index to assessment of the effects of the autonomic system on heart. In this study, the combination effect of nicotine and black tea consumption on sympatho-vagal balance and heart rate variability was investigated in rats. Male Wistar rats were randomized into four groups as control, tea (2.5 g/100 cc, daily), nicotine (2 mg/kg/d) and tea plus nicotine groups which treated for 28 days, and in the 29th day, their electrocardiograms (lead II) were recorded. The mean of high-frequency power (HF) in tea, nicotine and tea plus nicotine groups was significantly more than control group (P nicotine and tea + nicotine groups was significantly less than control group (P nicotine and tea + nicotine groups in comparison with control group (P nicotine or their combination with dosages used in this study can increase the heart rate variability and improve the sympatho-vagal balance in rat. © 2017 John Wiley & Sons Ltd.

Chronic activation of hypothalamic oxytocin neurons improves cardiac function during left ventricular hypertrophy-induced heart failure.

Science.gov (United States)

Garrott, Kara; Dyavanapalli, Jhansi; Cauley, Edmund; Dwyer, Mary Kate; Kuzmiak-Glancy, Sarah; Wang, Xin; Mendelowitz, David; Kay, Matthew W

2017-09-01

A distinctive hallmark of heart failure (HF) is autonomic imbalance, consisting of increased sympathetic activity, and decreased parasympathetic tone. Recent work suggests that activation of hypothalamic oxytocin (OXT) neurons could improve autonomic balance during HF. We hypothesized that a novel method of chronic selective activation of hypothalamic OXT neurons will improve cardiac function and reduce inflammation and fibrosis in a rat model of HF. Two groups of male Sprague-Dawley rats underwent trans-ascending aortic constriction (TAC) to induce left ventricular (LV) hypertrophy that progresses to HF. In one TAC group, OXT neurons in the paraventricular nucleus of the hypothalamus were chronically activated by selective expression and activation of excitatory DREADDs receptors with daily injections of clozapine N-oxide (CNO) (TAC + OXT). Two additional age-matched groups received either saline injections (Control) or CNO injections for excitatory DREADDs activation (OXT NORM). Heart rate (HR), LV developed pressure (LVDP), and coronary flow rate were measured in isolated heart experiments. Isoproterenol (0.01 nM-1.0 µM) was administered to evaluate β-adrenergic sensitivity. We found that increases in cellular hypertrophy and myocardial collagen density in TAC were blunted in TAC + OXT animals. Inflammatory cytokine IL-1β expression was more than twice higher in TAC than all other hearts. LVDP, rate pressure product (RPP), contractility, and relaxation were depressed in TAC compared with all other groups. The response of TAC and TAC + OXT hearts to isoproterenol was blunted, with no significant increase in RPP, contractility, or relaxation. However, HR in TAC + OXT animals increased to match Control at higher doses of isoproterenol. Activation of hypothalamic OXT neurons to elevate parasympathetic tone reduced cellular hypertrophy, levels of IL-1β, and fibrosis during TAC-induced HF in rats. Cardiac contractility parameters were

Heart rate turbulence as a marker of myocardial electrical instability in children with hypertrophic cardiomyopathy