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Sample records for heart rate conclusion

  1. Target Heart Rates

    Science.gov (United States)

    ... training heart rate, you have to know your resting heart rate . Your resting heart rate is the number of times your heart beats ... to the National Institute of Health, the average resting heart rate: for children 10 years and older, and adults ( ...

  2. Heart Rate and Exercise

    Science.gov (United States)

    Barbara Z. Tharp

    2009-01-01

    In this activity about heart health (on page 27 of the PDF), learners measure their heart rates after a variety of physical activities and compare the results with their resting heart rates, and with the heart rates of other learners in their groups. Learners also make predictions about their pulse rates. This lesson guide includes background information, setup and management tips, extension ideas, information about the heart in space and a handout.

  3. Target Heart Rate

    Science.gov (United States)

    Mr. Peterson

    2011-09-18

    Students will practice how to calculate their Target Heart Rate to use during exercise routines. This will help students monitor the intensity of their workouts, and ultimately help them achieve results from their workout. Standard 2: Objective 2: a,b,c Before we discuss what the Target Heart Range is and how we can us it, we must first have some basic knowledge of the heart and it's functions. Click the "habits of the heart" to learn the basics of the heart and how it circulates blood throughout the body. Habits of the Heart The hearts ...

  4. Tachycardia | Fast Heart Rate

    Science.gov (United States)

    ... down on alcohol. Quitting tobacco use. Getting more rest. In patients with Wolfe-Parkinson-White Syndrome , medications or ablation may be needed to control PSVT. Atrial or Supraventricular tachycardia (SVT) is a fast heart rate that starts in the upper chambers of the ...

  5. All about Heart Rate (Pulse)

    Science.gov (United States)

    ... of beats in 60 seconds, Stein said. Your resting heart rate is the heart pumping the lowest amount of ... Moderate physical activity doesn’t usually change the resting pulse much,” ... might have a heart rate between 60 and 100,” he added. That’s because ...

  6. Heart rate variability in healthy population

    International Nuclear Information System (INIS)

    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)

  7. HCN Channels and Heart Rate

    Directory of Open Access Journals (Sweden)

    Ilaria Dentamaro

    2012-04-01

    Full Text Available Hyperpolarization and Cyclic Nucleotide (HCN -gated channels represent the molecular correlates of the “funny” pacemaker current (If, a current activated by hyperpolarization and considered able to influence the sinus node function in generating cardiac impulses. HCN channels are a family of six transmembrane domain, single pore-loop, hyperpolarization activated, non-selective cation channels. This channel family comprises four members: HCN1-4, but there is a general agreement to consider HCN4 as the main isoform able to control heart rate. This review aims to summarize advanced insights into the structure, function and cellular regulation of HCN channels in order to better understand the role of such channels in regulating heart rate and heart function in normal and pathological conditions. Therefore, we evaluated the possible therapeutic application of the selective HCN channels blockers in heart rate control.

  8. Conclusion

    International Nuclear Information System (INIS)

    The carcinogenic effect of ionizing radiation has become the main issue in radioprotection since the data seem to show that the genetic effect is less important than was formerly thought. The hypothesis of a linear no threshold (LNT) relationship, which means that the hazard of carcinogenesis is proportional to dose, was introduced in 1965 (ICRP report no.9) in order to simplify the administrative assessment of cancer risk. The validity of the LNT relationship has been challenged by several senior radiation biologists. Hence, The Academie des Sciences felt that it was timely to organize a symposium during which proponents and opponents of LNT could calmly discuss the various facets of this problem. The first sessions were devoted to microdosimetry and DNA repair. The third part of the meeting was devoted to the mechanisms of carcinogenesis in humans. The discussion throughout the meeting emphasized the avenues which should be explored for a better understanding of human radioinduced carcinogenesis, in particular the dose effect relationship for ds DNA breaks and the impact of dose rate, apoptosis, radioinduced genetic instability, epigenetic effect, as well as epidemiological studies focused on the effect of low doses in patients and on individuals from the regions of the world where background natural irradiation is high. (N.C.)

  9. Baroreflex sensitivity and heart rate.

    Czech Academy of Sciences Publication Activity Database

    Halámek, Josef; Jurák, Pavel; Swenne, C. A.; Kára, T.; Sou?ek, M.; Eisenberg, M.; Nykodým, J.

    Brno : University of Technology VUTIUM Press, 2002 - (Kozumplík, J.; Provazník, I.; Jan, J.), s. 72 - 74 ISBN 80-214-2633-0. ISSN 1211-412X. [BIOSIGNAL 2002. Brno (CZ), 25.06.2002-28.06.2002] R&D Projects: GA ?R GA102/00/1262; GA ?R GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : baroreflex sensitivity * heart rate * blood flow Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  10. Influence of heart failure severity on heart rate variability

    Directory of Open Access Journals (Sweden)

    Zamaklar-Trifunovi? Danijela

    2005-01-01

    Full Text Available Introduction. Autonomic regulation of cardiovascular functions in congestive heart failure is characterised by enhanced sympathetic and diminished parasympathetic activity. The long term predominance of sympathetic tone is a significant factor in arrhythmogenesis, sudden cardiac death, and progressive pump failure. Heart rate variability (HRV is a noninvasive method for estimating the sympatho vagal balance in cardiovascular control. Aim. The aim of this study was to analyse the influence of heart failure severity on HRV. Method. HRV was estimated through the spectral analysis of short term ECG (Cardiovit AT 60, Schiller, CH in 63 patients (78% male, mean age 56.9±10.9 years and 14 healthy volunteers (57.1% male, mean age 53.1±8.2 years. The following spectral components were measured: VLF (very low frequency, LF (low frequency, HF (high frequency, and total power (Tot Power. Results. All spectral components were statistically, significantly lower in patients with heart failure in comparison to healthy controls (VLF: 159.89±147.02 vs. 285.50±202.77 ms2; p=0.023, LF: 161.48±204.01 vs. 474.57±362.93 ms2; p<0.001, HF: 88.58±102.47 vs. 362.71±318.28 ms2; p<0.001, as well as total power (Tot Power: 723.39±644.52 vs. 1807.29±1204.74 ms2; p<0.001. A significant, negative correlation between HRV parameters and NYHA class was detected in heart failure patients (VLF: r=-0.391; p=0.002, LF: r=-0.401; p=0.001, and Tot Power r=-0.372; p=0.003. Ejection fraction proved to be in significant, positive correlation to VLF (r=0.541; p=0.002, LF (r=0.531; p=0.003, HF (r=0.418; p=0.020, and Tot Power (r=0.457; p=0.013. Conclusion. Significant HRV reduction is a precursor to incipient heart failure (NYHA I. In heart failure progression, total power as well as the power of all spectral components is progressively reduced. LF and Tot Power are the most prominent parameters for discriminating between the different stages of heart failure. These results could promote HRV as an important decision-making tool in heart failure treatment as well as in monitoring the results of that treatment.

  11. Heart rate recovery after exercise: relations to heart rate variability and complexity

    Scientific Electronic Library Online (English)

    M., Javorka; I., Zila; T., Balhárek; K., Javorka.

    2002-08-01

    Full Text Available Physical exercise is associated with parasympathetic withdrawal and increased sympathetic activity resulting in heart rate increase. The rate of post-exercise cardiodeceleration is used as an index of cardiac vagal reactivation. Analysis of heart rate variability (HRV) and complexity can provide use [...] ful information about autonomic control of the cardiovascular system. The aim of the present study was to ascertain the association between heart rate decrease after exercise and HRV parameters. Heart rate was monitored in 17 healthy male subjects (mean age: 20 years) during the pre-exercise phase (25 min supine, 5 min standing), during exercise (8 min of the step test with an ascending frequency corresponding to 70% of individual maximal power output) and during the recovery phase (30 min supine). HRV analysis in the time and frequency domains and evaluation of a newly developed complexity measure - sample entropy - were performed on selected segments of heart rate time series. During recovery, heart rate decreased gradually but did not attain pre-exercise values within 30 min after exercise. On the other hand, HRV gradually increased, but did not regain rest values during the study period. Heart rate complexity was slightly reduced after exercise and attained rest values after 30-min recovery. The rate of cardiodeceleration did not correlate with pre-exercise HRV parameters, but positively correlated with HRV measures and sample entropy obtained from the early phases of recovery. In conclusion, the cardiodeceleration rate is independent of HRV measures during the rest period but it is related to early post-exercise recovery HRV measures, confirming a parasympathetic contribution to this phase.

  12. Heart rate recovery after exercise: relations to heart rate variability and complexity

    Directory of Open Access Journals (Sweden)

    M. Javorka

    2002-08-01

    Full Text Available Physical exercise is associated with parasympathetic withdrawal and increased sympathetic activity resulting in heart rate increase. The rate of post-exercise cardiodeceleration is used as an index of cardiac vagal reactivation. Analysis of heart rate variability (HRV and complexity can provide useful information about autonomic control of the cardiovascular system. The aim of the present study was to ascertain the association between heart rate decrease after exercise and HRV parameters. Heart rate was monitored in 17 healthy male subjects (mean age: 20 years during the pre-exercise phase (25 min supine, 5 min standing, during exercise (8 min of the step test with an ascending frequency corresponding to 70% of individual maximal power output and during the recovery phase (30 min supine. HRV analysis in the time and frequency domains and evaluation of a newly developed complexity measure - sample entropy - were performed on selected segments of heart rate time series. During recovery, heart rate decreased gradually but did not attain pre-exercise values within 30 min after exercise. On the other hand, HRV gradually increased, but did not regain rest values during the study period. Heart rate complexity was slightly reduced after exercise and attained rest values after 30-min recovery. The rate of cardiodeceleration did not correlate with pre-exercise HRV parameters, but positively correlated with HRV measures and sample entropy obtained from the early phases of recovery. In conclusion, the cardiodeceleration rate is independent of HRV measures during the rest period but it is related to early post-exercise recovery HRV measures, confirming a parasympathetic contribution to this phase.

  13. Scale Invariant Properties in Heart Rate Signals

    International Nuclear Information System (INIS)

    The rate of heart beat is controlled by autonomic nervous system: accelerated by the sympathetic system and slowed by the parasympathetic system. Scaling properties in heart rate are usually related to the intrinsic dynamics of this physiological regulatory system. The two packages calculating local exponent spectra: Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis (accessible from Physionet home page http://circ.ahajournals.org/cgi/content/full/101/23/e215) are tested, and then used to investigate the spectrum of singularity exponents in series of heart rates obtained from patients suffering from reduced left ventricle systolic function. It occurs that this state of a heart could be connected to some perturbation in the regulatory system, because the heart rate appears to be less controlled than in a healthy human heart. The multifractality in the heart rate signal is weakened: the spectrum is narrower and moved to higher values what indicate the higher activity of the sympatethic nervous system. (author)

  14. Scale Invariant Properties in Heart Rate Signals

    Science.gov (United States)

    Makowiec, D.; Dudkowska, A.; Zwierz, M.; Galaska, R.; Rynkiewicz, A.

    2006-05-01

    The rate of heart beat is controlled by autonomic nervous system: accelerated by the sympathetic system and slowed by the parasympathetic system. Scaling properties in heart rate are usually related to the intrinsic dynamics of this physiological regulatory system. The two packages calculating local exponent spectra: Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis (accessible from Physionet home page http://circ.ahajournals.org/cgi/content/full/101/23/e215) are tested, and then used to investigate the spectrum of singularity exponents in series of heart rates obtained from patients suffering from reduced left ventricle systolic function. It occurs that this state of a heart could be connected to some perturbation in the regulatory system, because the heart rate appears to be less controlled than in a healthy human heart. The multifractality in the heart rate signal is weakened: the spectrum is narrower and moved to higher values what indicate the higher activity of the sympatethic nervous system.

  15. Heart rate reduction and longevity in mice.

    Science.gov (United States)

    Gent, Sabine; Kleinbongard, Petra; Dammann, Philip; Neuhäuser, Markus; Heusch, Gerd

    2015-03-01

    Heart rate correlates inversely with life span across all species, including humans. In patients with cardiovascular disease, higher heart rate is associated with increased mortality, and such patients benefit from pharmacological heart rate reduction. However, cause-and-effect relationships between heart rate and longevity, notably in healthy individuals, are not established. We therefore prospectively studied the effects of a life-long pharmacological heart rate reduction on longevity in mice. We hypothesized, that the total number of cardiac cycles is constant, and that a 15% heart rate reduction might translate into a 15% increase in life span. C57BL6/J mice received either placebo or ivabradine at a dose of 50 mg/kg/day in drinking water from 12 weeks to death. Heart rate and body weight were monitored. Autopsy was performed on all non-autolytic cadavers, and parenchymal organs were evaluated macroscopically. Ivabradine reduced heart rate by 14% (median, interquartile range 12-15%) throughout life, and median life span was increased by 6.2% (p = 0.01). Body weight and macroscopic findings were not different between placebo and ivabradine. Life span was not increased to the same extent as heart rate was reduced, but nevertheless significantly prolonged by 6.2%. PMID:25589054

  16. Heart rate and heart rate variability responses to Tai Chi and jogging in Beijing and Graz

    Directory of Open Access Journals (Sweden)

    Gerhard Litscher

    2011-02-01

    Full Text Available Background: Tai Chi is a famous training method in China, and jogging is a popular kind of exercise both in Austria and China. Nevertheless, there is little information concerning online monitoring of biosignals during both training activities in parallel. Within the last years innovative scientific monitoring tools for evaluating features of neurocardial fitness have been developed. Aims: The goal of this study was to demonstrate heart rate and heart rate variability analysis for the first time during Tai Chi and jogging. Volunteers and Methods: Continuous electrocardiographic monitoring over a period of 75 minutes was performed simultaneously in two healthy volunteers using the same type of equipment (medilog AR12 systems. Two healthy persons (both male, 49 years and 52 years, respectively, both hobby sportsmen, were monitored continuously during two resting periods before and after active sport and also during Tai Chi and jogging, respectively. Results: Data acquisition was performed without any technical problems in both subjects. Poincaré plots of sequential R-R intervals (beat to beat variability show two ellipses of different shape and magnitude. During resting periods blood pressure effects can be clearly seen in one subject (jogging. The same effects, however reduced, are obvious in the other volunteer during Tai Chi. Conclusions: The present investigations during Tai Chi and jogging highlight the potential value of heart rate and heart rate variability monitoring even under difficult conditions. The innovative kind of analysis helps to show how well the human body reacts to sport, stress and recovery.

  17. Heart rates of participants in wheelchair sports.

    Science.gov (United States)

    Coutts, K D

    1988-02-01

    The relative stress of participation in wheelchair basketball, volleyball, tennis, and racquetball were determined by monitoring the heart rates of wheelchair athletes. Heart rates were recorded for 5 seconds every 30 seconds during monitoring sessions of 10 min or longer under game or practice conditions. Subjects were volunteer paraplegic athletes with lesions below T5 or with equivalent disability according to an international sport classification system. Average heart rates were 89 beats/min for tennis 'practice', 96 for racquetball 'practice' 107 for volleyball 'practice', 114 for volleyball 'game', 127 for tennis 'game', 129 for basketball 'practice', 135 for racquetball 'game', and 149 for basketball 'game' conditions. The percentage of time when heart rates were above 140 beats/min, followed the same pattern as the average heart rates and ranged from 0 to 62%. PMID:3353125

  18. Metaiodobenzylguanidine and heart rate variability in heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Kurata, Chinori; Shouda, Sakae; Mikami, Tadashi; Uehara, Akihiko; Ishikawa, Keiko [Hamamatsu Univ., Shizuoka (Japan). School of Medicine; Tawarahara, Kei; Nakano, Tomoyasu; Matoh, Fumitaka; Takeuchi, Kazuhiko

    1998-10-01

    It is assumed that the low-frequency power (LF) of heart rate variability (HRV) increases with progress of congestive heart failure (CHF), therefore positively correlating with cardiac {sup 123}I-metaiodobenzylguanidine (MIBG) washout. It is demonstrated here that HRV, including normalized LF, correlated inversely with MIBG washout and positively with the ratio of heart-to-mediastinum MIBG activity in controls and CHF patients, whereas these correlations were not observed within CHF patients. Thus MIBG washout may increase and HRV including normalized LF may decrease with CHF, although the HRV and MIBG measures may not similarly change in proportion to the severity of the cardiac autonomic dysfunction in CHF. (author)

  19. Interdependence of parameters of varia-tional pulsometry, entropy of heart rate, temporal and spectral analyses of heart rate variability in normal state and in ischemic heart disease

    Directory of Open Access Journals (Sweden)

    Durnova N.Yu.

    2011-09-01

    Full Text Available The research goal is to study the correlation between indices of variational pulsometry, entropy of heart rate, temporal and spectral analyses and heart rate variability in healthy patients and patients with coronary heart disease. Materials. Of the study are indicators of variational pulsometry and temporal and spectral analyses from 111 patients with coronary heart disease and in 61 healthy individuals. Results. Most parameters of HRV correlated with each other. In healthy patients the greatest independence was characterized by Mo and LF/HF, in patients with coronary artery disease — only by LF/HF Significant correlation with SDNN RMSSD, TP, LF, HF was determined. Conclusion. The variational pulsometry, temporal and spectral analyses of HRV and entropy of heart rate provide HRV assessment. The indices are interdependent and indicate interchangeability of methods

  20. Heart rate recovery in patients with ischemic heart disease - risk factors

    Directory of Open Access Journals (Sweden)

    Cosmin Grad

    2014-12-01

    Full Text Available Background and aim. Central nervous system dysfunction is associated with mortality and morbidity in patients with cardiovascular disease, post-workout recovery and faster heart rate being mediated by the dynamic interaction between the sympathetic nervous system (SNS and the parasympathetic nervous system (PNS, as components of the autonomic nervous system. Heart rate recovery is the decline in heart rate after exercise. The aim of the study was to determine the influence of certain clinical and paraclinical parameters on heart rate recovery after exercise in patients with ischemic heart disease. Methods. The study included 260 patients who were subjected to cardiovascular stress test. The following parameters were measured in each patient: blood pressure and pulse rate prior to exercise, during exercise and at protocol-established time intervals, as well as 1 and 3 minutes after the end of the stress test. Statistical analysis was performed usingMedCalc software version 14.8.1 Results. Elderly patients had slower heart rate recovery at 1 minute after effort. Female patients have recovered significantly better the heart rate, at 1 minute and 3 minutes after effort compared to the males. This difference was maintained in multivariate analysis, independent of age or comorbidities of patients. The presence of ischemic heart disease was the most important factor independently associated with HRR1.Triglyceride values were negatively correlated with both HRR3 and HRR1 and independent of other factors present in the multivariate analysis. Conclusions. Autonomic dysfunction is involved in the development of cardiovascular risk factors like hypertension, diabetes, dyslipidemia and was directly correlated with morbidity and mortality caused by coronary heart disease.

  1. Ear Acupressure, Heart Rate, and Heart Rate Variability in Patients with Insomnia

    OpenAIRE

    Lu Wang; Weiping Cheng; Zhongren Sun; Yangyang Xu; Guangyu Cheng; Ingrid Gaischek; Haixue Kuang; Gerhard Litscher

    2013-01-01

    This high-tech “teleacupuncture study” describes a neurovegetative ear acupressure effect in patients with chronic insomnia by using heart rate variability analysis. Heart rate (HR) and heart rate variability (HRV) measurements in 31 patients (mean age?±?SD: 54.3?±?10.6 years) were performed under standardized conditions in Harbin, China, and the data analysis was performed in Graz, Austria. Similar to our previous clinical and basic teleacupuncture research works, the electroca...

  2. Heart Rate Sensor for Freshwater Mussels

    Science.gov (United States)

    Just, C. L.; Vial, D. P.; Kruger, A.; Niemeier, J. J.; Lee, H. W.; Schroer, H. W.

    2014-12-01

    Researchers have long been interested the cardiac activity of mollusks. First, it is important as a basic measure of the animal's metabolism. Further, activities such as feeding and burrowing affect heart rate, as do environmental factors such as water salinity, water temperature, exposure, and predation. We have developed a small, noninvasive sensor for measuring freshwater mussel heart rate. Its working principle is as follows. An infrared (IR) light-emitting diode is placed in contact with the mussel shell. Some of the IR penetrates through the shell, reflects off internal organs, and traverses back. A photodetector detects this IR, and electronics condition the signal. The heartbeat of the animal modulates the IR, allowing one to measure the heart rate. The technique is widely-used in finger heart-rate monitors in humans. The sensors do not have to be positioned above the heart and several locations on the mussel shell work well. The sensor is small (8 mm × 10 mm) and consumes less than 1 mA, and has a simple one-wire interface that allows for easy integration into data acquisition hardware. We present heart rate measurements for the common pocketbook (lampsilis cardium) freshwater mussel.

  3. Heart Rate Variability in Obstructive Sleep Apnea.

    Directory of Open Access Journals (Sweden)

    Selvakumar Jagannathan

    2013-06-01

    Full Text Available Introduction: Obstructive Sleep Apnea (OSA is characterized by repeated episodes of upper airway obstruction leading to increased airway resistance and respiratory effort, producing oxygen desaturation, hypercapnia and central nervous system arousal. The intermittent hypoxemia and carbon-dioxide retention is responsible for the changes in autonomic and hemodynamic responses to sleep. Heart rate variability (HRV is a marker of autonomic activity and can be analyzed using time-domain and frequency-domain methods. This study was undertaken to compare the HRV in patients with Obstructed Sleep Apnoea Syndrome (OSAS and normal subjects. Methods: Heart rate variability in 30 controls (Group I and 30 patients with Obstructive Sleep Apnea Syndrome (Group II aged 35-45 yrs was studied by using electrocardiographic data obtained during Polysomnography. Low frequency (LF power, High frequency (HF power and Low frequency/ High frequency ratio (LF/HF were analyzed using frequency-domain analysis. Results: There was a significant difference (p <0.001 in LF power and LF/HF ratio of patients with OSAS when compared to the controls, with the values of the OSAS patients being higher, indicating a strong sympathetic activity and a significant difference (p <0.001 in HF power, with the values of the OSAS patients being lower, suggesting parasympathetic blunting.Conclusion: In our study, there was evidence of increased Sympathetic activity and a Parasympathetic attenuation in patients with Obstructive Sleep Apnea. Further studies can evaluate the usefulness of HRV indices for the non-invasive screening of asymptomatic patients suspected to have OSAS.

  4. The relationship between phase and heart rate

    International Nuclear Information System (INIS)

    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 concln 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)

  5. 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.

  6. Heart rate variability and its relation to ventricular arrhythmias in congestive heart failure.

    OpenAIRE

    Fei, L; Keeling, P J; Gill, J. S.; Bashir, Y; Statters, D. J.; Poloniecki, J.; McKenna, W J; Camm, A J

    1994-01-01

    BACKGROUND--It has been shown that heart rate variability is decreased in patients with congestive heart failure and that depressed heart rate variability is associated with a propensity to ventricular arrhythmias. Little is known, however, about heart rate variability in patients with both congestive heart failure and ventricular arrhythmias. METHODS--Spectral heart rate variability was analysed from 24 hour ambulatory electrocardiograms in 15 controls, 15 patients with non-sustained ventric...

  7. Music determines heart rate variability of singers

    OpenAIRE

    RebeckaJörnsten; BjörnVickhoff; HelgeMalmgren; RickardÅström; GunnarNyberg; MathiasEngvall; JohanSnygg; MichaelNilsson

    2013-01-01

    Choir singing is known to promote wellbeing. One reason for this may be that singing demands a slower than normal respiration which may in turn affect heart activity. Coupling of heart rate variability (HRV) to respiration is called Respiratory sinus arrhythmia (RSA). This coupling has a subjective as well as a biologically soothing effect, and it is beneficial for cardiovascular function. RSA is seen to be more marked during slow-paced breathing and at lower respiration rates (0.1 Hz and bel...

  8. A Novel Thermal Measurement for Heart Rate

    Directory of Open Access Journals (Sweden)

    Bin Jing

    2013-09-01

    Full Text Available Heart rate is an important indicator for the mental and physical state, but it is usually measured through physical contact. In this paper, a novel non-contact method of heart rate measurement has been proposed from the infrared sequence images. First, a square region of interest (ROI was manually selected to cover the temple on the first frame. Then a head movement detection algorithm based on the centroid coordinate change of the extracted skin area was applied to the infrared sequence images, and according to the movement result, the ROI location in subsequent frames could be identified. After that, the distance between the gravity center and the top-left corner in every ROI is computed to get a time-lapse signal. Finally, the discrete wavelet transform and an autoregressive model were used respectively to recognize the heart rate. Fourteen healthy subjects (24-29 years of age, 4 females and 10 males participated in the experiment. Compared with the concomitant ECG, mean accuracy rate of 94.5% was acquired. The results show the potential of our method for non-contact heart rate measurement.

  9. Wireless monitoring of Heart Rate using Microcontroller

    Directory of Open Access Journals (Sweden)

    J.S. Prasath

    2013-02-01

    Full Text Available This paper describes the development of wireless monitoring of a heart rate based on a microcontroller. We can record the ECG signals and Heart beats of all patients in a single computer. These biomedical signals are acquired and then processed with a microcontroller. After processing, all data are sent to a communication interface that can send this information to a personal computer. For the patient suffering from the cardiac disease it is very necessary to perform accurate and quick diagnosis. For this purpose a continuous monitoring of the ECG signal, patient’s current heart rate and BP are essential. We can monitor the patient’s ECG signal by using Bluetooth transmission and reception in the central place in any hospital. The MATLAB software is used to simulate the ECG waveform.

  10. [Heart rate modulation in stable ischemic heart disease: what we have learned from the SIGNIFY study?].

    Science.gov (United States)

    Perna, Gian Piero; Battistoni, Ilaria; Angelini, Luca

    2015-03-01

    Elevated heart rate is a marker of cardiovascular risk in patients with stable coronary artery disease. The addition of ivabradine to standard therapy to reduce heart rate did not improve outcomes in the recent SIGNIFY trial. Moreover, a significant interaction between the effect of ivabradine among subgroups with and without angina with a worse outcome in patients in CCS class >II at baseline was detected. The explanation for this surprising finding despite a significant reduction in angina and myocardial revascularization procedures is uncertain. A J-curve for heart rate was not demonstrated. We speculate a significant interference on adverse events (mainly atrial fibrillation and consequently acute coronary syndromes) and on the outcome of unfavorable interactions between ivabradine and diltiazem, verapamil and strong inhibitors of CYP3A4 (4.6% of the total population). Excluding this subgroup, there are no significant changes in outcomes between the two treatment groups (ivabradine and placebo). In conclusion, heart rate is a marker of risk but is not a risk factor and/or a target of therapy in patients with stable coronary artery disease and preserved ventricular systolic function. Standard doses of ivabradine are indicated for treatment of angina as an alternative or in addition to beta-blockers, but should not be administered in association with CYP3A4 inhibitors or heart rate-lowering calcium antagonists. PMID:25837459

  11. Heart Rate Variability and Blood Pressure during Dynamic and Static Exercise at Similar Heart Rate Levels

    OpenAIRE

    Weippert, Matthias; Behrens, Kristin; Rieger, Annika; Stoll, Regina; Kreuzfeld, Steffi

    2013-01-01

    Aim was to elucidate autonomic responses to dynamic and static (isometric) exercise of the lower limbs eliciting the same moderate heart rate (HR) response. Method: 23 males performed two kinds of voluntary exercise in a supine position at similar heart rates: static exercise (SE) of the lower limbs (static leg press) and dynamic exercise (DE) of the lower limbs (cycling). Subjective effort, systolic (SBP) and diastolic blood pressure (DBP), mean arterial pressure (MAP), rate pressure product...

  12. Effect of endotoxemia on heart rate dynamics in rat isolated perfused hearts

    Directory of Open Access Journals (Sweden)

    Mohammad Karim Azadbakht

    2013-03-01

    Full Text Available Introduction: Beat-to-beat variation in heart rate shows a complex dynamics, and this complexity is changed during systemic inflammatory response syndrome (e.g. sepsis. It is not known whether or not cardiac pacemaker dynamical rhythm is affected by sepsis. The aim of this study was to investigate heart rate dynamics of isolated heart as well as expression of pacemaker channels (HCN in a rat model of sepsis (endotoxemia compared with normal rats. Methods: Male rats weighing 250-300 g were used in this study. Bacterial lipopolysaccharide was injected intraperitoneally (1mg/kg in the endotoxemia group, and sterile saline in the control group. Three hours after injection, cardiac tissues were isolated and studied using Langendorff apparatus. Heart rate dynamics was assessed by calculating the standard deviation of inter-beat intervals as well as detrended fluctuation analysis (DFA. Quantitative RT-PCR was used to assess HCN expression in atria. Results: Hypoxia had a significantly different effect on heart rate variability in endotoxemic rats compared with controls (P<0.05. DFA analysis showed a linear relationship between logarithm of variance and the logarithm of scale in both endotoxemic and control rats. Atrial expression of HCN1 and HCN2 at mRNA level were significantly higher in endotoxemic rats in comparison with controls (P<0.05. Conclusion: Spontaneous beatings of isolated hearts exhibit a fractal-like dynamics which did not change after global hypoxia and/or endotoxemia. Endotoxemia was associated with altered heart rate variability and increased expression of pacemaker channels that might play a role in pathophysiology of cardiac complications of sepsis.

  13. Music determines heart rate variability of singers

    Directory of Open Access Journals (Sweden)

    RebeckaJörnsten

    2013-07-01

    Full Text Available Choir singing is known to promote wellbeing. One reason for this may be that singing demands a slower than normal respiration which may in turn affect heart activity. Coupling of heart rate variability (HRV to respiration is called Respiratory sinus arrhythmia (RSA. This coupling has a subjective as well as a biologically soothing effect, and it is beneficial for cardiovascular function. RSA is seen to be more marked during slow-paced breathing and at lower respiration rates (0.1 Hz and below. In this study, we investigate how singing, which is a form of guided breathing, affects HRV and RSA. The study comprises a group of healthy 18 year olds of mixed gender. The subjects are asked to; (1 hum a single tone and breathe whenever they need to; (2 sing a hymn with free, unguided breathing; and (3 sing a slow mantra and breathe solely between phrases. Heart rate (HR is measured continuously during the study. The study design makes it possible to compare above three levels of song structure. In a separate case study, we examine five individuals performing singing tasks (1-(3. We collect data with more advanced equipment, simultaneously recording HR, respiration, skin conductance and finger temperature. We show how song structure, respiration and heart rate are connected. Unison singing of regular song structures makes the hearts of the singers accelerate and decelerate simultaneously. Implications concerning the effect on wellbeing and health are discussed as well as the question how this inner entrainment may affect perception and behavior.

  14. Heart rate and heart rate variability responses to Tai Chi and jogging in Beijing and Graz

    OpenAIRE

    Gerhard Litscher; Weibo Zhang; Tao Huang; Lu Wang

    2011-01-01

    Background: Tai Chi is a famous training method in China, and jogging is a popular kind of exercise both in Austria and China. Nevertheless, there is little information concerning online monitoring of biosignals during both training activities in parallel. Within the last years innovative scientific monitoring tools for evaluating features of neurocardial fitness have been developed. Aims: The goal of this study was to demonstrate heart rate and heart rate variability analysis for the first t...

  15. Effects of aerobic training on heart rate

    Scientific Electronic Library Online (English)

    Marcos B., Almeida; Claudio Gil S., Araújo.

    2003-04-01

    Full Text Available Regular physical exercise is an important factor to reduce the indexes of cardiovascular and all causes morbimortality. However, there is, apparently, additional and independent benefits of the regular practice of physical exercise and the improvement of the level of aerobic condition. Heart rate (H [...] R) is mediated primarily by the direct activity of the autonomic nervous system (ANS), specifically through the sympathetic and parasympathetic branches activities over the sinus node autorhythmicity, with predominance of the vagal activity (parasympathetic) at rest, that is progressively inhibited since the onset of the exercise. The HR behavior has been widely studied during different conditions and protocols associated to the exercise. A reduction of the cardiac vagal tone (parasympathetic function) and consequently a diminished HR variability in rest, independently of the protocol of measurement used, is related to an autonomic dysfunction, chronic-degenerative diseases and increased mortality risk. Individuals with high levels of aerobic condition have a lower resting HR, along with a larger parasympathetic activity or smaller sympathetic activity, but it is not necessarily a direct consequence of the exercise training, as long as other inherent adaptations to the aerobic conditioning can influence the resting HR. The HR response in the onset of the exercise represents the integrity of the vagus nerve, and the HR recovery on the post-exercise transient also denotes important prognostic information; by the way, individuals that have a slow HR recovery in the first minute post-exercise have increased mortality risk. In conclusion, the physiological mechanisms modulating HR during or after an exercise program are not totally clear, and further studies are needed.

  16. Effects of aerobic training on heart rate

    Directory of Open Access Journals (Sweden)

    Marcos B. Almeida

    2003-04-01

    Full Text Available Regular physical exercise is an important factor to reduce the indexes of cardiovascular and all causes morbimortality. However, there is, apparently, additional and independent benefits of the regular practice of physical exercise and the improvement of the level of aerobic condition. Heart rate (HR is mediated primarily by the direct activity of the autonomic nervous system (ANS, specifically through the sympathetic and parasympathetic branches activities over the sinus node autorhythmicity, with predominance of the vagal activity (parasympathetic at rest, that is progressively inhibited since the onset of the exercise. The HR behavior has been widely studied during different conditions and protocols associated to the exercise. A reduction of the cardiac vagal tone (parasympathetic function and consequently a diminished HR variability in rest, independently of the protocol of measurement used, is related to an autonomic dysfunction, chronic-degenerative diseases and increased mortality risk. Individuals with high levels of aerobic condition have a lower resting HR, along with a larger parasympathetic activity or smaller sympathetic activity, but it is not necessarily a direct consequence of the exercise training, as long as other inherent adaptations to the aerobic conditioning can influence the resting HR. The HR response in the onset of the exercise represents the integrity of the vagus nerve, and the HR recovery on the post-exercise transient also denotes important prognostic information; by the way, individuals that have a slow HR recovery in the first minute post-exercise have increased mortality risk. In conclusion, the physiological mechanisms modulating HR during or after an exercise program are not totally clear, and further studies are needed.

  17. Heart rate and heart rate variability in dogs with different degrees of myxomatous mitral valve disease

    DEFF Research Database (Denmark)

    Rasmussen, Caroline Elisabeth; Falk, Bo Torkel

    2011-01-01

    HEART RATE AND HEART RATE VARIABILITY IN DOGS WITH DIFFERENT DEGREES OF MYXOMATOUS MITRAL VALVE DISEASE. CE Rasmussen1, T Falk1, NE Zois1, SG Moesgaard1, HD Pedersen2, J Häggström3 and LH Olsen1. 1. Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark. 2. Novo Nordic A/S, Maaloev, Denmark. 3. Department of Clinical Sciences, Swedish University of Agricultural Science, Uppsala, Sweden. Heart rate variability (HRV) is an indirect measurement of the autonomic modulation of heart rate (HR). Reduced HRV measured from short-time electrocardiography is seen in dogs with heart failure (HF) secondary to myxomatous mitral valve disease (MMVD). However, HRV is suggested to increase with disease severity at early stages of MMVD. The aims of this study were 1) to associate HR and HRV with severity of MMVD in Cavalier King Charles Spaniels (CKCS) and 2) to compare HR and HRV between CKCS and other dog breeds in a group of dogs in HF secondary toMMVD. One-hundred dogs were examined by echocardiography and 24-hour electrocardiography. The dogs were divided into five groups: 1) CKCS with no/minimal mitral regurgitation (MR) (MR jet=15% of the left atrial area using color Doppler mapping) and no murmur, 2) CKCS with mild MR (20%50%) and no clinical signs of HF, 4) CKCS in HF (HF defined as left atrium to aortic root ratio (LA/Ao) >1.5, clinical signs of HF and furosemide responsiveness) and 5) non-CKCS in HF. Dogs in HF were allowed HF therapy. Both HR and HRV were analysed over a 24-hour period, while HRV were also analysed over a 6-hour nightly period. Analyses of variance were performed with HR or HRV as response variables and the explanatory variables dog group and echocardiographic indices of MMVD were included separately. All P-values were Bonferroni corrected. Minimum- and mean HR were significantly higher in CKCS with moderate/severe MR and in HF compared to CKCS with no/minimal and mild MR (all P<0.001). Seven out of 26 HRV variables were significantly decreased in CKCS with moderate/severe MR and in HF compared to CKCS with no/minimal and mild MR (all P<0.02). Another 10 HRV variables showed the same groupwise differences (all P<0.02), except that the difference between CKCS with mild MR and CKCS with moderate/severe MR did not reach statistical significance. Minimum HR, mean HR and the HRV variables (7 and 10) differing between dog groups, also consistently decreased with increasing MR, LA/Ao and the proximal isovelocity surface area in CKCS. Non-CKCS in HF had a lower minimum HR compared to CKCS in HF (P=0.03) and a higher triangular index measured in both periods (all P<0.04). In conclusion, HR increased and most HRV variables decreased with increasing severity of MMVD in CKCS, even prior to the development of HF. Other breeds in HF secondary to MMVD had lower minimum HR, but higher triangular index compared to CKCS in HF.

  18. Multiscale power analysis for heart rate variability

    Science.gov (United States)

    Zeng, Peng; Liu, Hongxing; Ni, Huangjing; Zhou, Jing; Xia, Lan; Ning, Xinbao

    2015-06-01

    We first introduce multiscale power (MSP) method to assess the power distribution of physiological signals on multiple time scales. Simulation on synthetic data and experiments on heart rate variability (HRV) are tested to support the approach. Results show that both physical and psychological changes influence power distribution significantly. A quantitative parameter, termed power difference (PD), is introduced to evaluate the degree of power distribution alteration. We find that dynamical correlation of HRV will be destroyed completely when PD>0.7.

  19. Quantitative analysis of heart rate variability

    OpenAIRE

    Kurths, Ju?rgen; Voss, A.; Witt, Annette; Saparin, P.; Kleiner, H. J.; Wessel, N.

    1994-01-01

    In the modern industrialized countries every year several hundred thousands of people die due to the sudden cardiac death. The individual risk for this sudden cardiac death cannot be defined precisely by common available, non-invasive diagnostic tools like Holter-monitoring, highly amplified ECG and traditional linear analysis of heart rate variability (HRV). Therefore, we apply some rather unconventional methods of nonlinear dynamics to analyse the HRV. Especially, some complexity meas...

  20. Heart Rate Variability in Obstructive Sleep Apnea.

    OpenAIRE

    Selvakumar Jagannathan; Cruz, Suzanne Maria D.; Valarmathy Selvakumar; Vishwanatha Rao Badanidiyur

    2013-01-01

    Introduction: Obstructive Sleep Apnea (OSA) is characterized by repeated episodes of upper airway obstruction leading to increased airway resistance and respiratory effort, producing oxygen desaturation, hypercapnia and central nervous system arousal. The intermittent hypoxemia and carbon-dioxide retention is responsible for the changes in autonomic and hemodynamic responses to sleep. Heart rate variability (HRV) is a marker of autonomic activity and can be analyzed using time-domain and fre...

  1. The predictive value of resting heart rate following osmotherapy in brain injury: back to basics

    Directory of Open Access Journals (Sweden)

    Hasanpour Mir Mahsa

    2012-12-01

    Full Text Available Abstract Background The importance of resting heart rate as a prognostic factor was described in several studies. An elevated heart rate is an independent risk factor for adverse cardiovascular events and total mortality in patients with coronary artery disease, chronic heart failure, and the general population. Also heart rate is elevated in the Multi Organ Dysfunction Syndrome (MODS and the mortality due to MODS is highly correlated with inadequate sinus tachycardia. To evaluate the value of resting heart rate in predicting mortality in patients with traumatic brain injury along scoring systems like Acute Physiology and Chronic Health Evaluation(APACHE II, Sequential Organ Failure Assessment (SOFA and Glasgow Coma Score (GCS. Method By analyzing data which was collected from an open labeled randomized clinical trial that compared the different means of osmotherapy (mannitol vs bolus or infusion hypertonic saline, heart rate, GCS, APACHE II and SOFA score were measured at baseline and daily for 7 days up to 60 days and the relationship between elevated heart rate and mortality during the first 7 days and 60th day were assessed. Results After adjustments for confounding factors, although there was no difference in mean heart rate between either groups of alive and expired patients, however, we have found a relative correlation between 60th day mortality rate and resting heart rate (P=0.07. Conclusion Heart rate can be a prognostic factor for estimating mortality rate in brain injury patients along with APACHE II and SOFA scores in patients with brain injury.

  2. Model-based heart rate prediction during Lokomat walking

    OpenAIRE

    Koenig A.C.; Somaini L.; Pulfer M.; Holenstein T.; Omlin X.; Wieser M; Riener R.

    2009-01-01

    We implemented a model for prediction of heart rate during Lokomat walking. Using this model, we can predict potential overstressing of the patient and adapt the physical load accordingly. Current models for treadmill based heart rate control neglect the fact that the interaction torques between Lokomat and human can have a significant effect on heart rate. Tests with five healthy subjects lead to a model of sixth order with walking speed and power expenditure as inputs and heart rate predict...

  3. Heart Rate During Sleep: Implications for Monitoring Training Status

    OpenAIRE

    Waldeck, Miriam R.; Lambert, Michael I.

    2003-01-01

    Resting heart rate has sometimes been used as a marker of training status. It is reasonable to assume that the relationship between heart rate and training status should be more evident during sleep when extraneous factors that may influence heart rate are reduced. Therefore the aim of the study was to assess the repeatability of monitoring heart rate during sleep when training status remained unchanged, to determine if this measurement had sufficient precision to be used as a marker of train...

  4. Heart rate turbulence analysis in female patients with fibromyalgia

    Scientific Electronic Library Online (English)

    Huseyin, Dursun; Ersel, Onrat; Emine, Ercan; Umit Secil, Demirdal; Alaettin, Avsar; Umit, Dundar; Ozlem, Solak; Hasan, Toktas.

    2015-04-01

    Full Text Available OBJECTIVE: Fibromyalgia is characterized by diffuse musculoskeletal pain and discomfort. There are several reports regarding autonomic nervous system dysfunction in patients with fibromyalgia. Heart rate turbulence is expressed as ventriculophasic sinus arrhythmia and has been considered to reflect [...] cardiac autonomic activity. Heart rate turbulence has been shown to be an independent and powerful predictor of sudden cardiac death in various cardiac abnormalities. The aim of this study is to determine whether heart rate turbulence is changed in female patients with fibromyalgia compared with healthy controls. METHODS: Thirty-seven female patients (mean age, 40±11 years) with fibromyalgia, and 35 age- and sex-matched healthy female control subjects (mean age, 42±9 years) were included. Twenty-four hours of ambulatory electrocardiography recordings were collected for all subjects, and turbulence onset and turbulence slope values were automatically calculated. RESULTS: The baseline clinical characteristics of the two groups were similar. There were no significant differences in turbulence onset and turbulence slope measures between patients and control subjects (turbulence onset: ?1.648±1.568% vs. ?1.582±1.436%, p???0.853; turbulence slope: 12.933±5.693 ms/RR vs. 13.639±2.505 ms/RR, p???0.508). Although body mass index was negatively correlated with turbulence slope (r????0.258, p???0.046), no significant correlation was found between body mass index and turbulence onset (r???0.228, p???0.054). CONCLUSION: To the best of our knowledge, this is the first study to evaluate heart rate turbulence in patients with fibromyalgia. It appears that heart rate turbulence parameters reflecting cardiac autonomic activity are not changed in female patients with fibromyalgia.

  5. Heart rate turbulence analysis in female patients with fibromyalgia

    Science.gov (United States)

    Dursun, Huseyin; Onrat, Ersel; Ercan, Emine; Demirdal, Umit Secil; Avsar, Alaettin; Dundar, Umit; Solak, Ozlem; Toktas, Hasan

    2015-01-01

    OBJECTIVE: Fibromyalgia is characterized by diffuse musculoskeletal pain and discomfort. There are several reports regarding autonomic nervous system dysfunction in patients with fibromyalgia. Heart rate turbulence is expressed as ventriculophasic sinus arrhythmia and has been considered to reflect cardiac autonomic activity. Heart rate turbulence has been shown to be an independent and powerful predictor of sudden cardiac death in various cardiac abnormalities. The aim of this study is to determine whether heart rate turbulence is changed in female patients with fibromyalgia compared with healthy controls. METHODS: Thirty-seven female patients (mean age, 40±11 years) with fibromyalgia, and 35 age- and sex-matched healthy female control subjects (mean age, 42±9 years) were included. Twenty-four hours of ambulatory electrocardiography recordings were collected for all subjects, and turbulence onset and turbulence slope values were automatically calculated. RESULTS: The baseline clinical characteristics of the two groups were similar. There were no significant differences in turbulence onset and turbulence slope measures between patients and control subjects (turbulence onset: ?1.648±1.568% vs. ?1.582±1.436%, p???0.853; turbulence slope: 12.933±5.693 ms/RR vs. 13.639±2.505 ms/RR, p???0.508). Although body mass index was negatively correlated with turbulence slope (r????0.258, p???0.046), no significant correlation was found between body mass index and turbulence onset (r???0.228, p???0.054). CONCLUSION: To the best of our knowledge, this is the first study to evaluate heart rate turbulence in patients with fibromyalgia. It appears that heart rate turbulence parameters reflecting cardiac autonomic activity are not changed in female patients with fibromyalgia. PMID:26017798

  6. 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.

  7. Gender differences of heart rate variability in healthy volunteers

    International Nuclear Information System (INIS)

    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, SDNNifemales. 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)

  8. Heart rate analysis in normal subjects of various age groups

    Directory of Open Access Journals (Sweden)

    Ping Luk

    2004-07-01

    Full Text Available Abstract Background Analysis of heart rate variation (HRV has become a popular noninvasive tool for assessing the activities of the autonomic nervous system (ANS. HRV analysis is based on the concept that fast fluctuations may specifically reflect changes of sympathetic and vagal activity. It shows that the structure generating the signal is not simply linear, but also involves nonlinear contributions. Linear parameters, Power spectral indice (LF/HF is calculated with nonlinear indices Poincare plot geometry(SD1,SD2, Approximate Entropy (ApEn, Largest Lyapunov Exponent (LLE and Detrended Fluctuation Analysis(DFA. The results show that, with aging the heart rate variability decreases. In this work, the ranges of all linear and nonlinear parameters for four age group normal subjects are presented with an accuracy of more than 89%. As a pre-analysis step, the HRV data is tested for nonlinearity using surrogate data analysis and the results exhibited a significant difference in the ApEn, LLE, SD1/SD2 and DFA parameters of the actual data and the surrogate data. Methods The heart rate is analyzed using the various time domain parameters, frequency domain parameter and nonlinear parameters like Poincare geometry, ApEn, LLE and DFA. Results In this work, the different linear and nonlinear parameters evaluated show a particular range for various cardiac abnormalities. And the results of these were subjected to 't' test with more than 89% confidence interval giving excellent 'p' values in all cases. Conclusions Heart rate variability (HRV signal can be used as a reliable indicator of state of the heart. It becomes less random with the aging(less chaotic. This is evaluated by using various time domain, frequency domain and nonlinear parameters like SD1/SD2, ApEn, LLE ?s and ?l. Different ranges of non-linear parameters for various age groups are presented with 'p' value ? 0.12.

  9. HEART RATE DURING SLEEP: IMPLICATIONS FOR MONITORING TRAINING STATUS

    Directory of Open Access Journals (Sweden)

    Miriam R. Waldeck

    2003-12-01

    Full Text Available Resting heart rate has sometimes been used as a marker of training status. It is reasonable to assume that the relationship between heart rate and training status should be more evident during sleep when extraneous factors that may influence heart rate are reduced. Therefore the aim of the study was to assess the repeatability of monitoring heart rate during sleep when training status remained unchanged, to determine if this measurement had sufficient precision to be used as a marker of training status. The heart rate of ten female subjects was monitored for 24 hours on three occasions over three weeks whilst training status remained unchanged. Average, minimum and maximum heart rate during sleep was calculated. The average heart rate of the group during sleep was similar on each of the three tests (65 ± 9, 63 ± 6 and 67 ± 7 beats·min-1 respectively. The range in minimum heart rate variation during sleep for all subjects over the three testing sessions was from 0 to 10 beats·min-1 (mean = 5 ± 3 beats·min-1 and for maximum heart rate variation was 2 to 31 beats·min-1 (mean = 13 ± 9 beats·min-1. In summary it was found that on an individual basis the minimum heart rate during sleep varied by about 8 beats·min-1. This amount of intrinsic day-to-day variation needs to be considered when changes in heart rate that may occur with changes in training status are interpreted

  10. Spectral analysis of heart rate variability in bronchial asthma.

    OpenAIRE

    Garrard, Cs; Seidler, A.; Mckibben, A.; Mcalpine, Le; Gordon, D.

    1992-01-01

    Sympathetic and parasympathetic activity was evaluated in ten healthy controls, nine asymptomatic, untreated asthmatic subjects and ten asthmatic patients during treatment for acute asthma, by measurement of the variation in resting heart rate using frequency spectrum analysis. Heart rate was recorded by ECG and respiratory rate by impedance plethysmography. Spectral density of the beat-to-beat heart rate was measured within the low frequency band 0.04 to 0.10 Hz (low frequency power) modulat...

  11. Relationship between anxiety, heart rate and efficiency of pistol shooting

    Directory of Open Access Journals (Sweden)

    Gürhan Kayihan

    2014-06-01

    Full Text Available The purpose of this study was to investigate the relationship between anxiety, heart rate and efficiency of pistol shooting. In this study, 291 male volunteers working for the Turkish National Police within the age range of 20-23 years participated. The efficiency of pistol shooting was evaluated by the total points of the bullets which hit the target from 10 metres. The State-Trait Anxiety Inventory (STAI was used to assess anxiety. The “Polar Team2 Pro” device for heart rate was used. Significant differences were found between the sets of participants according to shot accuracy groups for state anxiety level, anxiety variability, average heart rate, maximal heart rate and heart rate changes. The correlation coefficient between the pistol shooting result and change in heart rate, anxiety variability, mean heart rate during shooting, state anxiety and maximal heart rate during shooting was significant. However, there was no significant correlation between shot accuracy and resting heart rate and trait anxiety. Based on the findings, it was concluded that as a result of the higher state anxiety levels, the tremor which is caused by increased heart rate negatively affects the shooting performance in police.

  12. Heart Rate Variability in Patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Kawser Jahan, Noorzahan Begum, Sultana Ferdousi

    2012-12-01

    Full Text Available Background: Altered cardiovascular autonomic nerve function with impaired sympathovagal balance is found in rheumatoid arthritis (RA. Heart Rate Variability (HRV analysis is an important tool for assessment of autonomic nerve activity.Objective: To assess cardiac autonomic nerve function status in patients with Rheumatoid arthritis (RA by time domain measures of HRV.Methods: This cross sectional study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU, Dhaka from January to December 2010. Sixty female RA patients, age range 18-50 years were constituted study group enrolled from the Out- patient Rheumatology Wing, Department of Medicine, BSMMU. Age matched thirty apparently healthy females were studied as control. Time domain measures of Heart Rate Variability (HRV such as Mean RR intervals, Mean HR, SDNN, RMSSD, NN50% and PNN 50% were recorded for 5 minutes by a Polygraph machine to observe cardiac autonomic nerve function activity. Data were analyzed by independent sample t test.Results: Mean R-R interval, SDNN, RMSSD, PNN50%, NN50% were significantly lower (p<0.001 but heart rate was significantly (P<0.001 higher in rheumatoid arthritis patients.Conclusion: Cardiac autonomic nerve function is impaired and characterized by reduced resting parasympathetic activity in female Rheumatoid Arthritis patients.

  13. Poincare indices for analyzing meditative heart rate signals

    Directory of Open Access Journals (Sweden)

    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.

  14. Variations in circadian heart rate in psychiatric disorders: theoretical and practical implications

    Directory of Open Access Journals (Sweden)

    Stampfer HG

    2013-04-01

    Full Text Available HG Stampfer,1 SB Dimmitt2 1School of Psychiatry and Clinical Neurosciences, University of Western Australia, 2School of Medicine and Pharmacology, University of Western Australia, Crawley, WA, AustraliaBackground: Data are presented to demonstrate dimensions of variation in circadian heart rate in patients under treatment for a psychiatric disorder and to comment on their clinical relevance.Method: Serial recordings of 24-hour heart rates were obtained from individuals under treatment for a psychiatric disorder and from healthy volunteers.Results: The mean 24-hour heart rate can vary independently of the circadian rate pattern or “rate architecture.” Sleep and waking heart rate can vary independently. Variations in circadian heart rate are state-dependent: broadly different clinical states are associated with distinctly different patterns of circadian heart rate, particularly during sleep.Conclusion: Different regulatory mechanisms or pathways are involved in mediating different aspects of circadian heart rate. An analysis of circadian heart rate can contribute useful physiological adjunct information to psychiatric assessment and the monitoring of patient response to treatment.Keywords: anxiety, depression, neuroendocrine regulation

  15. Loss of lag-response curvilinearity of indices of heart rate variability in congestive heart failure

    Directory of Open Access Journals (Sweden)

    Smith Michael L

    2006-06-01

    Full Text Available Abstract Background Heart rate variability (HRV is known to be impaired in patients with congestive heart failure (CHF. Time-domain analysis of ECG signals traditionally relies heavily on linear indices of an essentially non-linear phenomenon. Poincaré plots are commonly used to study non-linear behavior of physiologic signals. Lagged Poincaré plots incorporate autocovariance information and analysis of Poincaré plots for various lags can provide interesting insights into the autonomic control of the heart. Methods Using Poincaré plot analysis, we assessed whether the relation of the lag between heart beats and HRV is altered in CHF. We studied the influence of lag on estimates of Poincaré plot indices for various lengths of beat sequence in a public domain data set (PhysioNet of 29 subjects with CHF and 54 subjects with normal sinus rhythm. Results A curvilinear association was observed between lag and Poincaré plot indices (SD1, SD2, SDLD and SD1/SD2 ratio in normal subjects even for a small sequence of 50 beats (p value for quadratic term 3 × 10-5, 0.002, 3.5 × 10-5 and 0.0003, respectively. This curvilinearity was lost in patients with CHF even after exploring sequences up to 50,000 beats (p values for quadratic term > 0.5. Conclusion Since lagged Poincaré plots incorporate autocovariance information, these analyses provide insights into the autonomic control of heart rate that is influenced by the non-linearity of the signal. The differences in lag-response in CHF patients and normal subjects exist even in the face of the treatment received by the CHF patients.

  16. Heart rate variability interventions for concussion and rehabilitation

    OpenAIRE

    RobertLakeConder; AlannaA.Conder

    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 ...

  17. 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

    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 out in an age-stratified subsample of 131 subjects in the Copenhagen City Heart Study (CCHS). METHODS: Casual RHR was assessed from electrocardiograms recorded during clinical assessment. Hourly daytime HRs were mapped by Holter recording. Holter RHR was defined as the average of the lowest 3 hourly HRs recorded and mean HR calculated from all daytime HRs. Follow-up was recorded from public registers. Outcome measure was hazard rate for the combined endpoint of cardiovascular mortality, non-fatal heart failure and non-fatal acute myocardial infarction. Comparison of casual RHR, Holter RHR and mean HR by Multivariate Cox regression was performed. RESULTS: A total of 57 composite endpoints occurred during 17.1 years of follow-up. Regression analysis suggests correlation between Casual RHR and Holter RHR. Multivariate Cox regression analysis adjusted for gender and age demonstrated hazard rates of 1.02 (p = 0.079) for casual RHR, 1.04 (p = 0.036*) for Holter RHR, and 1.03 (p = 0.093) for mean HR for each 10 beat increment in HR. CONCLUSIONS: In a comparative analysis on the correlation and significance of differing RHR measurement modalities RHR measured by 24-hour Holter recording was found to be marginally superior as a predictor of cardiovascular morbidity and mortality. The results presented here do not however warrant the abandonment of a tested epidemiological variable.

  18. Heart Rate Variability Analysis in Different Age and Pathological Conditions

    Directory of Open Access Journals (Sweden)

    M. E.S. Chelladurai

    2011-01-01

    Full Text Available Problem statement: Heart Rate Variability (HRV has been used as a measure of mortality primarily with patients who had undergone cardiac surgery. The analysis of Heart Rate Variability (HRV demands specific capabilities which are not provided either by parametric or nonparametric conventional estimation methods. The Empirical Mode Decomposition (EMD adaptively estimates the Intrinsic Mode Functions (IMFs of nonlinear nonstationary signals. Approach: The intrinsic mode functions estimated from the HRV signal were based on local characteristics of the signal. The principle objective was to analyze the HRV latencies of healthy subjects in different age and pathological conditions. The method was applied to HRV signal of 17 healthy young control subjects, 17 healthy old control subjects and 20 congestive heart failure patients for half hour duration. Results: The results showed that a healthy person?s HRV rapidly rises to its maximum response much earlier than the HRV of pathological subjects. The rising slope of the time scale?s plot discriminates the healthy controls and pathological subjects with 100% sensitivity and specificity. Conclusion: This fact makes the method a promising approach to be applied in clinical practice as a screening test for specific risk-groups.

  19. Heart rate turbulence and variability in patients with ventricular arrhythmias

    Directory of Open Access Journals (Sweden)

    Diego Tarricone

    2009-08-01

    Full Text Available Background: To evaluate the changes in autonomic neural control mechanisms before malignant ventricular arrhythmias, we measured heart rate variability (HRV and heart rate turbulence (HRT in patients with ventricular tachycardia or fibrillation (Group I; n=6, non sustained ventricular tachycardia (Group II; n=32, frequent premature ventricular beats (Group III; n=26 and with ICD implantation (Group IV; n=11. Methods: Time domain parameters of HRV and turbulence onset (TO and slope (TS were calculated on 24 hour Holter recordings. Normal values were: SDNN > 70 msec for HRV, TO <0% and TS >2.5 msec/RR-I for HRT. Results: Whereas SDNN was within normal range and similar in all study groups, HRT parameters were significantly different in patients who experienced VT/VF during Holter recording. Abnormal TO and/or TS were present in 100% of Group I patients and only in about 50% of Group II and IV. On the contrary, normal HRT parameters were present in 40-70% of Group II, III and IV patients and none of Group I. Conclusions: These data suggest that HRT analysis is more suitable than HRV to detect those transient alterations in autonomic control mechanisms that are likely to play a major trigger role in the genesis of malignant cardiac arrhythmias. (Heart International 2007; 3: 51-7

  20. Match analysis and heart rate of futsal players during competition.

    Science.gov (United States)

    Barbero-Alvarez, J C; Soto, V M; Barbero-Alvarez, V; Granda-Vera, J

    2008-01-01

    Heart rates were monitored and time-motion analysis performed for 10 players (mean age 25.6 years, s = 2.5; body mass 73.8 kg, s = 5.7 kg; height 1.75 m, s = 0.06) during four competitive futsal matches. Mean heart rate during the match was 90% (s = 2) of maximum heart rate. Heart rate records were classified based on the percentage of time spent in three zones (>85%, 85-65%, and futsal is a multiple-sprints sport in which there are more high-intensity phases than in soccer and other intermittent sports. PMID:17899472

  1. Resting autonomic modulations and the heart rate response to exercise.

    OpenAIRE

    Nunan, D.; Jakovljevic, Dg; Donovan, G.; Singleton, Ld; Sandercock, Gr; Brodie, Da

    2010-01-01

    OBJECTIVES: Identify the underlying role of resting heart rate variability (HRV) in the hearts response to graded exercise testing (GXT). METHODS: Resting 5-min HRV and heart rate (HR) measurements were made in 33 volunteers (19 males, median age 34, range 25-63 years and 14 females median age 48, range 21-63 years). Measures of VO2 peak and HR obtained during a maximal GXT and heart rate recovery (HRR) post-GXT were assessed for associations with resting HRV. Differences and effect size (d) ...

  2. Heart rate dynamics during a treadmill cardiopulmonary exercise test in optimized beta-blocked heart failure patients

    OpenAIRE

    Vitor Oliveira Carvalho; Guilherme Veiga Guimarães; Emmanuel Gomes Ciolac; Edimar Alcides Bocchi

    2008-01-01

    BACKGROUND: Calculating the maximum heart rate for age is one method to characterize the maximum effort of an individual. Although this method is commonly used, little is known about heart rate dynamics in optimized beta-blocked heart failure patients. AIM: The aim of this study was to evaluate heart rate dynamics (basal, peak and % heart rate increase) in optimized beta-blocked heart failure patients compared to sedentary, normal individuals (controls) during a treadmill cardiopulmonary exer...

  3. Caffeine Consumption and Heart Rate and Blood Pressure Response to Regadenoson

    Science.gov (United States)

    Bitar, Abbas; Mastouri, Ronald; Kreutz, Rolf P.

    2015-01-01

    Background Current guidelines recommend that caffeinated products should be avoided for at least 12 hours prior to regadenoson administration. We intended to examine the effect of caffeine consumption and of timing of last dose on hemodynamic effects after regadenoson administration for cardiac stress testing. Methods 332 subjects undergoing regadenoson stress testing were enrolled. Baseline characteristics, habits of coffee/caffeine exposure, baseline vital signs and change in heart rate, blood pressure, percent of maximal predicted heart rate, and percent change in heart rate were prospectively collected. Results Non-coffee drinkers (group 1) (73 subjects) and subjects who last drank coffee >24 hours (group 3) (139 subjects) prior to regadenoson did not demonstrate any difference in systolic blood pressure, heart rate change, maximal predicted heart rate and percent change in heart rate. Systolic blood pressure change (15.2±17.1 vs. 7.2±10.2 mmHg, p = 0.001), heart rate change (32.2±14 vs. 27.3±9.6 bpm, p = 0.038) and maximal predicted heart rate (65.5±15.6 vs. 60.7±8.6%, p = 0.038) were significantly higher in non-coffee drinkers (group 1) compared to those who drank coffee 12–24 hours prior (group 2) (108 subjects). Subjects who drank coffee >24 hours prior (group 3) exhibited higher systolic blood pressure change (13±15.8 vs. 7±10.2, p = 0.007), and heart rate change (32.1±15.3 vs. 27.3±9.6, p = 0.017) as compared to those who drank coffee 12–24 hours prior to testing (group 2). Conclusions Caffeine exposure 12–24 hours prior to regadenoson administration attenuates the vasoactive effects of regadenoson, as evidenced by a blunted rise in heart rate and systolic blood pressure. These results suggest that caffeine exposure within 24 hours may reduce the effects of regadenoson administered for vasodilatory cardiac stress testing. PMID:26098883

  4. DETECTING CONGESTIVE HEART FAILURE USING HEART RATE SEQUENTIAL TREND ANALYSIS PLOT

    OpenAIRE

    SRINIVAS KUNTAMALLA,; Ram Gopal Reddy, L.

    2010-01-01

    Heart rate variability analysis is gaining acceptance as a potential non-invasive means of autonomic nervous system assessment in research as well as clinical domains. In this study, a nonlinear analysis method is developed to detect congestive heart failure. The data obtained from an online and widely used public database (i.e., MIT/BIH physionet database), is used for testing the performance of the method. The method developed is based on the sequential trend analysis plot of heart rate var...

  5. Heart rate variability and turbulence analysis in patients with psoriasis

    Directory of Open Access Journals (Sweden)

    Asuman Biçer

    2010-12-01

    Full Text Available Objectives: Psoriasis vulgaris (PV is a chronic inflammatory skin disorder with increased incidence of many systemic abnormalities. However, the effects of psoriasis on autonomic nervous system have not been previously well-defined. Impaired autonomic function with an increase in sympathetic activity may be associated with ventricular arrhythmias and sudden cardiac death in the general population. Heart rate turbulence (HRT is a noninvasive test to reflect the increased sympathetic tone and abnormal baroreflex sensitivity. The aim of current study was to investigate the effect of psoriasis on cardiac autonomic function by using HRT and heart rate variability (HRV parameters as possible indicators of increased risk for ventricular arrhythmias and sudden cardiac death.Materials and methods: The study comprised 20 psoriatic patients without cardiovascular involvement and age and sex matched 20 healthy subjects. The severity of the disease was evaluated by the “Psoriasis Area and Severity Index”. The HRV and turbulence analysis were assessed from a 24-hour Holter recording.Results: There were no statistically significant differences between the two groups with respect to clinical, demographic and biochemical characteristics. When HRT parameters were compared; the values of the turbulence onset and slope in psoriatic patients were not significantly different from the control group (p>0.05. HRV parameters except for high frequency power (significantly lower in psoriatic patients, p0.05.Conclusion: Psoriasis appeared not to be associated with impaired autonomic function regarding to HRT and HRV values. Further investigations are needed to confirm these results

  6. Serum AChE Activities Predict Exercise Heart Rate Parameters of Asymptomatic Individuals

    Directory of Open Access Journals (Sweden)

    Canaani Jonathan

    2010-12-01

    Full Text Available Background specific heart rate parameters notably associate with variable risks of cardiovascular disease and mortal-ity, however, to date there are no readily available blood tests associated with these parameters. Because of the estab-lished parasympathetic contributions towards cardiac regulation, we challenged the working hypothesis that serum acetylcholinesterase (AChE activity is involved. Methods A total of 403 Healthy men and women were included in the study and underwent treadmill exercise testing. Prior to exercise testing the subject’s serum AChE activity levels were assessed by measuring rates of acetylthiocholine hydrolysis. Results In male subjects AChE activity was positively cor-related to resting heart rate (r = 0.210, p = 0.001. Complementing this observation, AChE activity was negatively correlated to the exercise-induced heart rate increase (r = –0.181, p = 0.005 and to heart rate recovery at 1, 2 and 5 minutes following cessation of exercise (r = –0.150, p = 0.022; r = –0.157, p = 0.016; r = –0.176, p = 0.008 respec-tively. This indicated that lower than average AChE activities, which presumably reflect increased peripheral ACh levels, might be correlated to favorable heart rate parameters. Similar observations were made in female subjects, ex-cept for lack of correlation to their resting heart rate. Additionally, we observed that we were able to stratify subjects into two groups of significantly different AChE activity (p = 0.001 based on a cut point of heart rate recovery below 20 beats one minute after cessation of exercise. Conclusion In asymptomatic individuals lower than average AChE activity is associated with favorable indices of exercise-inducible heart rate increase as well as heart rate recovery. Future studies will be needed to evaluate the added prognostic significance gained by implementing this marker into routine practice.

  7. Effect of heart rate on hemodynamics in mitral stenosis

    International Nuclear Information System (INIS)

    Objective: To assess the effect of heart rate (HR) on haemodynamic parameters in patients with Mitral Stenosis (MS). Methodology: The study was conducted at Cardiology department, Lady Reading Hospital, Peshawar from November 2010 to April 2011. Patients with MS, regardless of severity, were included. Patients with severe heart failure, other valvular or structural heart disease were excluded. Echocardiographic parameters were recorded at slow and fast HR. Patients with tachycardia were given a-blockers and patients with bradycardia were given parenteral Atropine. Results: A total of 60 patients were included, females were 57 (78%). Mean age was 31+- 9 years. Mean slow and fast HR was 77+-12 bpm and 110+-13 bpm, respectively. Peak mitral valve gradient (PMVG) slow vs. fast HR was 12.8+-4.80 and 14.93+-7.18 mm Hg (p=0.000). Mean mitral valve gradient (MMVG) at slow vs. fast HR was 6.62+-3.29 and 8.15+-4.88 mm of Hg (p=0.000). E pulse Doppler (E) at slow vs. fast HR was 168+-35 and 181+-40 cm/s (p=0.013), / while E tissue Doppler (E ) velocity was 10.47+-2.81 and 10.97+-2.38 cm/s/ (P=0.098), respectively. E/E ratio for slow and fast HR was 17+-5.63 vs.17+-5.41 (P=0.792). Right ventricular systolic pressure (RVSP) at slow vs. fast HR was 44+-16 vs.49+-17.05 mm of Hg (P=0.001). The above parameters had insignificant change with the HR when there was accompanying more than mild MR. Conclusion: Slowing HR in patients with MS significantly decreased PMVG, MMVG and RVSP. LV fcantly decreased PMVG, MMVG and RVSP. LV function did not change significantly with HR. Rate control drugs may be used in preference to improve symptoms in moderate and severe MS. (author)

  8. Original paper
    Heart rate variability in adult patients with congenital heart disease

    OpenAIRE

    Olga Trojnarska; Piotr Br?borowicz; Magdalena ?anocha; Maciej Lesiak; Wies?aw Bryl; Andrzej Cie?li?ski

    2005-01-01

    Introduction: Heart rate variability (HRV) illustrates an autonomic nervous system influence on the sinus node. It is known that low HRV parameters indicate poor prognosis in patients with myocardial infarction, predict sudden cardiac death and death due to heart failure. Adult population with congenital heart disease (CongHD) is particularly exposed to these complications. The aim of this study was to evaluate HRV parameters in adult patients with CongHD and to analyse the impact of the spec...

  9. 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. PMID:24128278

  10. Statistical analysis of heart rate and heart rate variability monitoring through the use of smart phone cameras.

    Science.gov (United States)

    Bolkhovsky, Jeffrey B; Scully, Christopher G; Chon, Ki H

    2012-01-01

    Video recordings of finger tips made using a smartphone camera contain a pulsatile component caused by the cardiac pulse equivalent to that present in a photoplethysmographic signal. By performing peak detection on the pulsatile signal it is possible to extract a continuous heart rate signal. We performed direct comparisons between 5-lead electrocardiogram based heart rate variability measurements and those obtained from an iPhone 4s and Motorola Droid derived pulsatile signal to determine the accuracy of heart rate variability measurements obtained from the smart phones. Monitoring was performed in the supine and tilt positions for independent iPhone 4s (2 min recordings, n=9) and Droid (5 min recordings, n=13) experiments, and the following heart rate and heart rate variability parameters were estimated: heart rate, low frequency power, high frequency power, ratio of low to high frequency power, standard deviation of the RR intervals, and root mean square of successive RR-differences. Results demonstrate that accurate heart rate variability parameters can be obtained from smart phone based measurements. PMID:23366214

  11. Time- and state-dependent analysis of autonomic control in narcolepsy: higher heart rate with normal heart rate variability independent of sleep fragmentation.

    Science.gov (United States)

    van der Meijden, Wisse P; Fronczek, Rolf; Reijntjes, Robert H A M; Corssmit, Eleonora P M; Biermasz, Nienke R; Lammers, Gert Jan; van Dijk, J Gert; Thijs, Roland D

    2015-04-01

    Narcolepsy with hypocretin deficiency is known to alter cardiovascular control during sleep, but its aetiology is disputed. As cardiovascular control differs between sleep states, and narcolepsy affects sleep architecture, controlling for both duration and transitions of sleep states is necessary. This study therefore aimed to assess heart rate and its variability in narcolepsy during sleep taking these factors into account. The study included 12 medication-naïve patients with narcolepsy with cataplexy and hypocretin deficiency (11 male, 16-53 years old), and 12 sex- and age-matched healthy controls (11 male, 19-55 years). All subjects underwent 1-night ambulatory polysomnography recording. Cardiovascular parameters were calculated for each 30-s epoch. Heart rate was significantly higher in patients with narcolepsy than in controls in all sleep states and during wakefulness prior to sleep. Groups did not differ in heart rate variability measures. The effects of sleep state duration on heart rate and its variability were similar between patients and controls. In conclusion, heart rate was consistently higher in patients with narcolepsy than controls, independent of sleep stage and sleep fragmentation. A direct effect of hypocretin deficiency therefore seems probable. PMID:25382307

  12. Heart rate, ischaemic heart disease, and sudden cardiac death in middle-aged British men.

    OpenAIRE

    Shaper, A. G.; Wannamethee, G.; Macfarlane, P. W.; Walker, M.

    1993-01-01

    OBJECTIVE--To examine the relation between resting heart rate and new major ischaemic heart disease events in middle aged men with and without pre-existing ischaemic heart disease. DESIGN--Prospective study of a cohort of men with eight years follow up for cardiovascular morbidity and mortality for all men. SETTING--General practices in 24 British towns (the British Regional Heart study). SUBJECTS--7735 men aged 40-59 years drawn at random from the age-sex registers of one general practice in...

  13. Monofractality in RR Heart Rate by Multifractal Tools

    International Nuclear Information System (INIS)

    Multifractal formalism is tested if it can work as a robust estimator of monofractals when scaling intervals are fixed. Intervals for scaling are selected to be consistent with known frequency bands of power spectral analysis used in estimates of heart rate variability: low frequency (LF), very low frequency (VLF), and ultra low frequency (ULF). Tests on fractional Brownian motions and a binomial cascade are performed to validate popular multifractal methods: Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis. Then the methods are applied to identify monofractal elements of control processes driving the heart rate. A transition is found in the dynamic organization of autonomic nervous system control of the heart rate related to the change in scaling intervals. The control over the diurnal heart rate is of a multifractal type when considered in LF and of a monofractal type when observed in ULF. Additionally, this transition affects on a switch in a relation between widths of diurnal and nocturnal multifractal spectra. (author)

  14. Heart rate variability in infants with West syndrome

    DEFF Research Database (Denmark)

    MØller, Michelle Mai; HØgenhaven, Hans

    2015-01-01

    PURPOSE: West syndrome (WS) is a severe age-related acute epileptic encephalopathy of infancy characterized by infantile spasms, hypsarrhythmia and psychomotor delay. The aim of this study was to investigate if patients with WS had an altered autonomic output to the heart. METHODS: In 23 patients with WS the heart rate variability (HRV) was investigated by examining time- and frequency-domain parameters of HRV at the time of the diagnosis of hypsarrhythmia and compared to 22 age-matched controls. For the WS patients the same dataset was obtained and compared again at the end of the study period, when hypsarrhythmia was no longer present. RESULTS: Compared to controls, patients with WS during hypsarrhythmia had significantly lower SDNN (the standard deviation of the NN interval, i.e. the square root of variance) (19.2ms; p=0.007, Mann-Whitney's U-Test) and total power (242ms(2); p=0.044, Mann-Whitney's U-Test) in the awake state, indicating an abnormal autonomic output to the heart. Comparing the initial to the final examination demonstrated a significant increase in the HRV parameters SDNN (31.3ms) and total power (757ms(2); p=0.001 and p=0.013, Wilcoxon Signed Ranked Test). In addition, at the final examination the WS-patients no longer differed significantly from the controls. CONCLUSION: Our data suggest that the initial reduction in HRV in patients at the time of onset of WS is transient and related to the presence of hypsarrhythmia.

  15. Heart Rate Variability Analysis in Different Age and Pathological Conditions

    OpenAIRE

    Chelladurai, M. E. S.; Kumaravel, N.

    2011-01-01

    Problem statement: Heart Rate Variability (HRV) has been used as a measure of mortality primarily with patients who had undergone cardiac surgery. The analysis of Heart Rate Variability (HRV) demands specific capabilities which are not provided either by parametric or nonparametric conventional estimation methods. The Empirical Mode Decomposition (EMD) adaptively estimates the Intrinsic Mode Functions (IMFs) of nonlinear nonstationary signals. Approach: The intrinsic mode functions estimated ...

  16. HEART RATE AND ACTIVITY PROFILE FOR YOUNG FEMALE SOCCER

    OpenAIRE

    J. Granda; Barbero-Álvarez, V; Gómez-López, M; Barbero-Álvarez, JC.; Castagna, C

    2008-01-01

    The physical and physiological demands of high-level male soccer have been studied extensively, while few studies have investigated the demands placed on females during match-play, however, there is no information available about the heart rate and activity profile of young female soccer players during match play. Therefore, the aim of this study was to examine cardiovascular (heart-rates HR) and physical demands of young female soccer players during a match. Players were observed during a fr...

  17. Heart Rate Variability Predicts ESRD and CKD-Related Hospitalization

    OpenAIRE

    Brotman, Daniel J.; Bash, Lori D.; Qayyum, Rehan; Crews, Deidra; Whitsel, Eric A.; Astor, Brad C.; Coresh, Josef

    2010-01-01

    Autonomic imbalance, a feature of both diabetes and hypertension, may contribute to adverse cardiovascular outcomes. In animal models, sympathetic nerve activity contributes to renal damage but the extent to which autonomic dysfunction precedes the development of CKD and ESRD in humans is unknown. We measured resting heart rate and heart rate variability in 13,241 adults (45- to 64-years old) followed for a median of 16 years in the Atherosclerosis Risk in Communities (ARIC) Study. We examine...

  18. Assessing resting heart rate in adolescents: determinants and correlates.

    OpenAIRE

    Veglio, Franco; Mulatero, Paolo

    2002-01-01

    The aim of this study was to evaluate the distribution of resting heart rate and its biological and environmental determinants in adolescents. The study was cross- sectional and the population consisted of 2230 children and adolescents, age range 12-18 years, enrolled randomly from state schools in Turin, Italy. In all participants the following parameters were evaluated: heart rate, blood pressure (BP), weight, height, degree of sexual development, physical activity, parental socio-cultural ...

  19. Using photoplethysmography in heart rate monitoring of patients with epilepsy.

    Science.gov (United States)

    van Andel, Judith; Ungureanu, Constantin; Aarts, Ronald; Leijten, Frans; Arends, Johan

    2015-04-01

    Heart rate is a useful neurophysiological sign when monitoring seizures in patients with epilepsy. In an ambulatory setting, heart rate is measured with ECG involving electrodes on the skin. This method is uncomfortable which is burdensome for patients and is sensitive to motion artifacts, which decrease the usability of measurements. In this study, green light photoplethysmography, an optical technique arising from the fitness industry, was evaluated for usefulness in a medical setting. Simultaneous overnight measurements of HR with a commercially available optical heart rate (OHR) sensor and with ECG (HRECG) were performed in 7 patients with epilepsy. Overall, there was no significant difference between OHR and HRECG in random 10-minute periods during wakefulness (p=0.69) and sleep (p=1.00). The Bland-Altman analysis showed negligible mean differences. Limits of agreement were higher during wakefulness and during the occurrence of two seizures possibly because of less reliable HRECG measurements due to motion artifacts. Optical heart rate seems less sensitive to these motion artifacts, and measurements are more user-friendly. The optical heart rate sensor may fill the gap of systems for ambulatory heart rate monitoring and can be especially useful in the context of seizure detection in patients with epilepsy. PMID:25812938

  20. DETECTING CONGESTIVE HEART FAILURE USING HEART RATE SEQUENTIAL TREND ANALYSIS PLOT

    Directory of Open Access Journals (Sweden)

    SRINIVAS KUNTAMALLA,

    2010-12-01

    Full Text Available Heart rate variability analysis is gaining acceptance as a potential non-invasive means of autonomic nervous system assessment in research as well as clinical domains. In this study, a nonlinear analysis method is developed to detect congestive heart failure. The data obtained from an online and widely used public database (i.e., MIT/BIH physionet database, is used for testing the performance of the method. The method developed is based on the sequential trend analysis plot of heart rate variability and correlates well with the characteristic autonomic nervous system regulations in congestive heart failure. The proposed method can be used for screening as well as diagnosing the heart failure patients. The algorithm is computationally simple and can be implemented in a real time processing hardware. This method classifies 31 out of 32 subjects and has the highest discrimination power in terms of sensitivity, specificity and accuracy.

  1. Age related reference ranges for respiration rate and heart rate from 4 to 16 years

    OpenAIRE

    Wallis, L.; Healy, M.; Undy, M; Maconochie, I.

    2005-01-01

    Background: Clinical vital signs in children (temperature, heart rate, respiration rate, and blood pressure) are an integral part of clinical assessment of degree of illness or normality. Despite this, only blood pressure and temperature have a reliable evidence base. The accepted ranges of heart and respiration rate vary widely.

  2. Heart Rate Variability Measures and Models

    CERN Document Server

    Teich, M C; Jost, B M; Vibe-Rheymer, K; Heneghan, C; Teich, Malvin C.; Lowen, Steven B.; Jost, Bradley M.; Vibe-Rheymer, Karin; Heneghan, Conor

    2001-01-01

    We focus on various measures of the fluctuations of the sequence of intervals between beats of the human heart, and how such fluctuations can be used to assess the presence or likelihood of cardiovascular disease. We examine sixteen such measures and their suitability for correctly classifying heartbeat records of various lengths as normal or revealing the presence of cardiac dysfunction, particularly congestive heart failure. Using receiver-operating-characteristic analysis we demonstrate that scale-dependent measures prove substantially superior to scale-independent ones. The wavelet-transform standard deviation at a scale near 32 heartbeat intervals, and its spectral counterpart near 1/32 cycles/interval, turn out to provide reliable results using heartbeat records just minutes long. We further establish for all subjects that the human heartbeat has an underlying stochastic origin rather than arising from a chaotic attractor. Finally, we develop a mathematical point process that emulates the human heartbea...

  3. Public and private heart rate feedback in social phobia: a manipulation of anxiety visibility.

    Science.gov (United States)

    Gerlach, Alexander L; Mourlane, Denis; Rist, Fred

    2004-01-01

    According to cognitive behavioural models of social phobia, bodily symptoms are the main source of information concerning social evaluation for social phobics. Experience and perception of bodily symptoms therefore play an important role in social anxiety. In this study we evaluated the effects of anxiety visibility on patients and controls using feedback of veridical heart sounds. A total of 32 social phobics and 32 controls were asked twice to sit in a chair and appear relaxed while being evaluated. Half of the participants heard their heart sounds first via headphones and then via loudspeakers which were also audible to observers. The presentation order of the heart sound was reversed for the other half of the subjects. Social phobics reported substantially more anxiety than controls. Both groups showed habituation in heart rate from the first to the second presentation, and both groups reported perception of a higher heart rate, but only social phobics reported significantly more anxiety and were more worried about their heart rates in the public than in the private condition. These effects were in excess of actual heart rate differences. In conclusion, social phobics worried about the broadcast of a bodily anxiety symptom, whereas controls did not. Information about arousal made public has a strong potential to increase anxiety levels in social phobics. PMID:15224627

  4. The relationship between heart rate reserve and oxygen uptake reserve in heart failure patients on optimized and non-optimized beta-blocker therapy

    Directory of Open Access Journals (Sweden)

    Vitor Oliveira Carvalho

    2008-01-01

    Full Text Available BACKGROUND: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exercise test. METHODS: A total of 27 sedentary heart failure patients (86% male, 50±12 years on optimized beta-blocker therapy with a left ventricle ejection fraction of 33±8% and 35 sedentary non-optimized heart failure patients (75% male, 47±10 years with a left ventricle ejection fraction of 30±10% underwent the treadmill cardiopulmonary exercise test (Naughton protocol. Resting and peak effort values of both the percentage of oxygen consumption reserve and percentage of heart rate reserve were, by definition, 0 and 100, respectively. RESULTS: The heart rate slope for the non-optimized group was derived from the points 0.949±0.088 (0 intercept and 1.055±0.128 (1 intercept, p<0.0001. The heart rate slope for the optimized group was derived from the points 1.026±0.108 (0 intercept and 1.012±0.108 (1 intercept, p=0.47. Regression linear plots for the heart rate slope for each patient in the non-optimized and optimized groups revealed a slope of 0.986 (almost perfect for the optimized group, but the regression analysis for the non-optimized group was 0.030 (far from perfect, which occurs at 1. CONCLUSION: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in patients on optimized beta-blocker therapy was reliable, but this relationship was unreliable in non-optimized heart failure patients.

  5. Heart Rate Variability in Complex Regional Pain Syndrome during Rest and Mental and Orthostatic Stress

    DEFF Research Database (Denmark)

    Terkelsen, Astrid J; MØlgaard, Henning

    2012-01-01

    BACKGROUND:: Complex regional pain syndrome (CRPS) is a pain condition with regional sensory and autonomic abnormalities in the affected limb. The authors studied systemic autonomic and hemodynamic function in CRPS patients during rest, and during orthostatic and mental arithmetic stress. METHODS:: Twenty patients with CRPS and 20 age-, sex-, and body mass index-matched control subjects participated. Mean values of heart rate variability, baroreceptor sensitivity, blood pressure, stroke volume, cardiac output, and total peripheral resistance were estimated during supine rest and 60° tilt-table testing. On a separate day, heart rate variability was also measured during mental arithmetic stress testing induced by a paced auditory serial addition task. RESULTS:: Heart rate was increased and heart rate variability reduced in patients with CRPS patients compared with control subjects during rest and mental and orthostatic stress, whereas baroreceptor sensitivity was unaffected. When tilted from supine to upright position, patients with CRPS were not able to preserve cardiac output in comparison with control subjects, and they exhibited an exaggerated increase in the total peripheral resistance. The hemodynamic changes correlated to pain duration but not to pain intensity. CONCLUSIONS:: The increased heart rate and decreased heart rate variability in CRPS suggest a general autonomic imbalance, which is an independent predictor for increased mortality and sudden death. The inability of the patients to protect their cardiac output during orthostatic stress was aggravated with the chronicity of the disease.

  6. The effect of competition on heart rate during kart driving: A field study

    Directory of Open Access Journals (Sweden)

    Yamakoshi Takehiro

    2011-09-01

    Full Text Available Abstract Background Both the act of competing, which can create a kind of mental stress, and participation in motor sports, which induces physical stress from intense g-forces, are known to increase heart rate dramatically. However, little is known about the specific effect of competition on heart rate during motor sports, particularly during four-wheel car driving. The goal of this preliminary study, therefore, was to investigate whether competition increases heart rate under such situations. Findings The participants drove an entry-level formula kart during two competitive races and during solo driving against the clock while heart rate and g-forces were measured. Analyses showed that heart rate values during the races (168.8 beats/min were significantly higher than those during solo driving (140.9 beats/min and rest (75.1 beats/min. Conclusions The results of this preliminary study indicate that competition heightens heart rate during four-wheel car driving. Kart drivers should be concerned about maintaining good health and developing physical strength.

  7. Decreased heart rate variability in surgeons during night shifts

    DEFF Research Database (Denmark)

    Amirian, Ilda; Toftegård Andersen, Lærke

    2014-01-01

    BACKGROUND: Heart rate variability (HRV) has been used as a measure of stress and mental strain in surgeons. Low HRV has been associated with death and increased risk of cardiac events in the general population. The aim of this study was to clarify the effect of a 17-hour night shift on surgeons' HRV. METHODS: Surgeons were monitored prospectively with an ambulatory electrocardiography device for 48 consecutive hours, beginning on a precall day and continuing through an on-call (17-h shift) day. We measured HRV by frequency domain parameters. RESULTS: We included 29 surgeons in our analysis. The median pulse rate was decreased precall (median 64, interquartile range [IQR] 56-70 beats per minute [bpm]) compared with on call (median 81, IQR 70-91 bpm, p < 0.001). Increased high-frequency (HF) activity was found precall (median 199, IQR 75-365 ms2) compared with on call (median 99, IQR 48-177 ms2, p < 0.001). The low-frequency:high-frequency (LF:HF) ratio was lower precall (median 2.7, IQR 1.9-3.9) than on call (median 4.9, IQR 3.7-6.5, p < 0.001). We found no correlation between the LF:HF ratio and performance in laparoscopic simulation. CONCLUSION: Surgeons working night shifts had a significant decrease in HRV and a significant increase in pulse rate, representing sympathetic dominance in the autonomic nervous system. TRIAL REGSISTRATION: NCT01623674 (www.clinicaltrials.gov).

  8. 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…

  9. Physiological control of intraaorta pump based on heart rate.

    Science.gov (United States)

    Gao, Bin; Nie, Li Ya; Chang, Yu; Zeng, Yi

    2011-01-01

    Because of the special structures of intraaorta pump, the pressure and blood flow sensors cannot be implanted in the blood pump. Moreover, the cardiovascular pump is a very complex system that has no accurate model but much uncertainty and disturbance. Hence, the conventional control algorithm cannot achieve good performance. To overcome this problem, on one hand, a cardiovascular pump model is established. The heart rate in this model is chosen as a controlled variable that is a nonlinear function of the mean arterial pressure. On the other hand, a fuzzy logic feedback control algorithm, which maintains the actual heart rate tracking the desired heart rate, is designed. Computer simulations are performed to verify the robustness and dynamic characters of the controller. The simulation results demonstrate that the controller can maintain the actual heart rate tracking the desired one without static error. When the desired heart rate changed from 100 to 80 bpm, the settling time is <10 seconds. When the peripheral resistance increases from 1.0 to 0.7 mm Hg/ml, the settling time is <10 seconds. PMID:21307771

  10. Heart rate changes during partial seizures: A study amongst Singaporean patients

    Directory of Open Access Journals (Sweden)

    Lim Shih-Hui

    2001-09-01

    Full Text Available Abstract Introduction Studies in Europe and America showed that tachycardia, less often bradycardia, frequently accompanied partial seizures in Caucasian patients. We determine frequency, magnitude and type of ictal heart rate changes during partial seizures in non-Caucasian patients in Singapore. Methods Partial seizures recorded during routine EEGs performed in a tertiary hospital between 1995 and 1999 were retrospectively reviewed. All routine EEGs had simultaneous ECG recording. Heart rate before and during seizures was determined and correlated with epileptogenic focus. Differences in heart rate before and during seizures were grouped into 4 types: (1 >10% decrease; (2 -10 to +20% change; (3 20–50% increase; (3 >50% increase. Results Of the total of 37 partial seizures, 18 were left hemisphere (LH, 13 were right hemisphere (RH and 6 were bilateral (BL in onset. 51% of all seizures showed no significant change in heart rate (type 2, 22% had moderate sinus tachycardia (type 3, 11% showed severe sinus tachycardia (type 4, while 16% had sinus bradycardia (type 1. Asystole was recorded in one seizure. Apart from having more tachycardia in bilateral onset seizures, there was no correlation between side of ictal discharge and heart rate response. Compared to Caucasian patients, sinus tachycardia was considerably less frequent. Frequency of bradycardia was similar to those recorded in the literature. Conclusions Significant heart rate changes during partial seizures were seen in half of Singaporean patients. Although sinus tachycardia was the most common heart rate change, the frequency was considerably lower compared to Caucasian patients. This might be due to methodological and ethnic differences. Rates of bradycardia are similar to those recorded in the literature.

  11. Effects of Moxa (Artemisia Vulgaris Smoke Inhalation on Heart Rate and Its Variability

    Directory of Open Access Journals (Sweden)

    Ping Liu

    2011-06-01

    Full Text Available Objective: To evaluate the changes of human heart rate (HR and heart rate variability (HRV during and after moxa smoke inhalation and to investigate the effects of moxa smoke on human autonomic nervous system. Methods: 24 healthy volunteers were exposed to moxa smoke with their HRV parameters measured before, during and after the moxa smoke inhalation. Results: The healthy volunteers exposed to moxa smoke had significant reductions in HR and also significant changes in HRV parameters. Conclusions: Moxa smoke can improve the autonomic nervous system activity. The inhalation of moxa smoke will induce a depressant effect on human body.

  12. Neuroanatomical substrates for the volitional regulation of heart rate

    Science.gov (United States)

    Jones, Catherine L.; Minati, Ludovico; Nagai, Yoko; Medford, Nick; Harrison, Neil A.; Gray, Marcus; Ward, Jamie; Critchley, Hugo D.

    2015-01-01

    The control of physiological arousal can assist in the regulation of emotional state. A subset cortical and subcortical brain regions are implicated in autonomic control of bodily arousal during emotional behaviors. Here, we combined human functional neuroimaging with autonomic monitoring to identify neural mechanisms that support the volitional regulation of heart rate, a process that may be assisted by visual feedback. During functional magnetic resonance imaging (fMRI), 15 healthy adults performed an experimental task in which they were prompted voluntarily to increase or decrease cardiovascular arousal (heart rate) during true, false, or absent visual feedback. Participants achieved appropriate changes in heart rate, without significant modulation of respiratory rate, and were overall not influenced by the presence of visual feedback. Increased activity in right amygdala, striatum and brainstem occurred when participants attempted to increase heart rate. In contrast, activation of ventrolateral prefrontal and parietal cortices occurred when attempting to decrease heart rate. Biofeedback enhanced activity within occipito-temporal cortices, but there was no significant interaction with task conditions. Activity in regions including pregenual anterior cingulate and ventral striatum reflected the magnitude of successful task performance, which was negatively related to subclinical anxiety symptoms. Measured changes in respiration correlated with posterior insula activation and heart rate, at a more lenient threshold, change correlated with insula, caudate, and midbrain activity. Our findings highlight a set of brain regions, notably ventrolateral prefrontal cortex, supporting volitional control of cardiovascular arousal. These data are relevant to understanding neural substrates supporting interaction between intentional and interoceptive states related to anxiety, with implications for biofeedback interventions, e.g., real-time fMRI, that target emotional regulation.

  13. Heart rate variability in patients being treated for Dengue viral infection: New insights from mathematical correction of heart rate

    Directory of Open Access Journals (Sweden)

    ROBERTCARTER III

    2014-02-01

    Full Text Available Introduction: Severe dengue hemorrhagic fever (DHF is a viral infection that acts to increase permeability of capillaries, resulting in internal hemorrhage. Linear frequency domain Fourier spectral analysis represents the most published noninvasive tool for diagnosing and assessing health status via calculated heart rate variability (HRV. As such, HRV may be useful in assessing clinical status in DHF patients, but is prone to erroneous results and conclusions due to the influence of the average HR during the time period of HRV assessment (defined as the ’prevailing’ HR. We tested the hypothesis that alterations in HRV calculated with linear frequency analysis would be minimal when mathematically corrected for prevailing HR following dengue viral infection. Methods: Male (N=16 and female (N= 11 patients between the ages of 6 months and 15 years of age (10 ± 6 SD years were tracked through the progression of the dengue viral infection with treatment following the abatement of a fever (defervescence. Electrocardiographic recordings were collected and analyzed for HRV. Results: High frequency (HF, low frequency (LF, and LF/HF ratio were unaffected by correction for prevailing HR. Conclusion: HRV corrected for changes in HR did not alter the interpretations of our data. Therefore, we conclude that cardiac parasympathetic activity (HF frequency is responsible for the majority of the HR reduction following defervescence in patients with dengue viral infection.

  14. Kramers-Moyal Expansion of Heart Rate Variability

    International Nuclear Information System (INIS)

    The first six Kramers-Moyal coefficients were extracted from human heart rate variability recordings. The method requires the determination of the Markov time and of the proper conditional probability densities. We analyzed heart rate data recorded in a group of ten young, healthy subjects. We obtained non-negligible higher order Kramers-Moyal (K-M) terms in 6 h nighttime parts of the 24 h recordings. This indicates that the data is a non-Gaussian process and probably a correlated signal. The analysis yielded important new insights into the character and distribution of the stochastic processes measured in healthy group. In the night hours, the dominant oscillation in the heart rate is the so called respiratory sinus arrhythmia (RSA)-a physiological phenomenon in which respiration acts as a drive for the heart rate. Certain kinds of pathology may disrupt RSA. We compared nighttime recordings of the healthy group with those recorded in six patients with hypertrophic cardiomyopathy (HCM). HCM is generally a pathology of heart cells but abnormalities in autonomic regulation are also observed. Using the higher order Kramers-Moyal coefficients, we analyzed the skewness and kurtosis in the nighttime recordings for the normal subjects. (author)

  15. Effect of partial sports massage on blood pressure and heart rate

    Directory of Open Access Journals (Sweden)

    Pystupa T.D.

    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.

  16. Generalised heart rate statistics reveal neurally mediated homeostasis transients

    Science.gov (United States)

    Makowiec, D.; Graff, B.; Miklaszewski, W.; Wejer, D.; Kaczkowska, A.; Budrejko, S.; Struzik, Z. R.

    2015-04-01

    Distributions of accelerations and decelerations, obtained from increments of heart rate recorded during a head-up tilt table (HUTT) test provide short-term characterization of the complex cardiovascular response to a rapid controlled dysregulation of homeostasis. A generalised statistic is proposed for evaluating the neural reflexes responsible for restoring the homeostatic dynamics. An evaluation of the effects on heart rate of the neural regulation involved in achieving homeostasis indicates a distinction between vasovagal patients and healthy subjects who are not susceptible to spontaneous fainting. A healthy cardiovascular response to the HUTT test is identified in the sympathetic tone appropriately punctuated by vagal activity.

  17. Relationship between anxiety, heart rate and efficiency of pistol shooting

    OpenAIRE

    Gürhan Kayihan; Gülfem Ersoz; Ali Özkan; Mercan Tuna

    2014-01-01

    The purpose of this study was to investigate the relationship between anxiety, heart rate and efficiency of pistol shooting. In this study, 291 male volunteers working for the Turkish National Police within the age range of 20-23 years participated. The efficiency of pistol shooting was evaluated by the total points of the bullets which hit the target from 10 metres. The State-Trait Anxiety Inventory (STAI) was used to assess anxiety. The “Polar Team2 Pro” device for heart rate was used. ...

  18. Thermoregulation mediated by conditioned heart-rate changes in pigeons

    OpenAIRE

    Delius, Juan; Sieland, Markus; Rautenberg, Werner; May, Bärbel

    1981-01-01

    Pigeons were subjected to an apparent heat (44 °C) or cold (30 °C) load by means of a thermode located next to their thermosensitive spinal cord. They were then able to obtain brief thermonormality (40 °C) spells if they changed their heart-rate by a preset amount above (or below) their baseline heartrate. In the final experiments the animals increased (or decreased) their heart-rate by about 25% within 12 training sessions, thereby achieving a partial thermoregulation: they were able to main...

  19. Music structure determines heart rate variability of singers

    OpenAIRE

    Vickhoff, Bjo?rn; Malmgren, Helge; A?stro?m, Rickard; Nyberg, Gunnar; Ekstro?m, Seth-reino; Engwall, Mathias; Snygg, Johan; Nilsson, Michael; Jo?rnsten, Rebecka

    2013-01-01

    Choir singing is known to promote wellbeing. One reason for this may be that singing demands a slower than normal respiration, which may in turn affect heart activity. Coupling of heart rate variability (HRV) to respiration is called Respiratory sinus arrhythmia (RSA). This coupling has a subjective as well as a biologically soothing effect, and it is beneficial for cardiovascular function. RSA is seen to be more marked during slow-paced breathing and at lower respiration rates (0.1 Hz and be...

  20. Entropies, Partitionings and Heart Rate Variability.

    Czech Academy of Sciences Publication Activity Database

    Paluš, Milan; Zebrowski, J.

    2009-01-01

    Ro?. 51, ?. 2 (2009), s. 65-72. ISSN 0001-7604 Institutional research plan: CEZ:AV0Z10300504 Keywords : coarse-grained entropy rate * HR variability * entropy Subject RIV: BB - Applied Statistics, Operational Research http://www.activitas.org/index.php/nervosa/article/view/25

  1. Prognostic significance of heart rate in hospitalized patients presenting with myocardial infarction

    Directory of Open Access Journals (Sweden)

    Lorenzo Fácila

    2012-01-01

    Full Text Available AIM: To investigate the prognostic significance of resting heart rate in patients with acute coronary syndrome (ACS, independent of other known factors. METHODS: Patients 40 years of age or older who had been admitted with acute coronary syndrome (ACS to one of the 94 hospitals participating in the Prevalence of Peripheral Arterial Disease in Patients with Acute Coronary Syndrome (PAMISCA study were included. Patients were divided into two groups based on their resting heart rate (HR ? or < 70 bpm. Complications were recording during a follow-up period of 1 year. RESULTS: There were 1054 ACS patients analyzed (43.5% with ST segment elevation and 56.5% without elevation. Mean age was 66.6 ± 11.7 years, 70.6% were male and 29.4% of subjects were female. During follow-up, more patients in the HR ? 70 bpm group were hospitalized for heart failure and they also had a higher mortality rate. In the multivariate analysis, a heart rate of ? 70 bpm was independently related to overall mortality during the follow-up period (hazard ratio 2.5; 95% confidence interval, 1.26-4.97, P = 0.009. CONCLUSION: A resting heart rate ? 70 bpm in patients who survive an ACS is an indicator of a high risk of suffering cardiovascular events during follow-up.

  2. Interchangeability between heart rate and photoplethysmography variabilities during sympathetic stimulations

    International Nuclear Information System (INIS)

    Photoplethysmography variability (PPGV) is currently considered to be a good surrogate to heart rate variability (HRV) measurements using the time between two pulse waves instead of RR intervals. Nevertheless, the interchangeability between HRV and PPGV has never been evaluated in situations with severe alterations in the autonomic nervous system (ANS). We aimed to identify the conditions for a correct utilization of PPGV in evaluating the consequences of sympathetic stimulations. Nine subjects performed three tests: active orthostatic test, slow walk and moderate and exhaustive cycling exercises in the supine position. Pulse waves at the fingertip and RR intervals were recorded at the same time. We used correlations and the Bland and Altman method to compare and evaluate interchangeability between several HRV indices. Bland and Altman analysis highlighted small discrepancies between PPGV and HRV for all HRV indices in the supine position and for LFms2, HFms2, LFpeak and RMSSD in the upright position. During the slow walk, it was impossible to detect properly PPG peaks. We observed large differences between the two methods during the cycling exercise. In conclusion, PPGV can be used instead of HRV without reserve in the supine position but only for some HRV indices in the upright position and not during slow walk and cycling exercise

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

    OpenAIRE

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

    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-...

  4. On direct sequential analysis of heart rate variability signals

    Directory of Open Access Journals (Sweden)

    Baji? Dragana

    2005-01-01

    Full Text Available Heart rate variability analysis represents one of the most promising and the most commonly used quantitative measures of the cardiovascular autonomic regulatory system. The analysis includes traditional statistical analytical tools and a number of new methods based on nonlinear system theory, recently developed to give better insight into complex HR. This paper introduces a direct sequential analysis.

  5. Heart Rate Variability: Effect of Exercise Intensity on Postexercise Response

    Science.gov (United States)

    James, David V. B.; Munson, Steven C.; Maldonado-Martin, Sara; De Ste Croix, Mark B. A.

    2012-01-01

    The purpose of the present study was to investigate the influence of two exercise intensities (moderate and severe) on heart rate variability (HRV) response in 16 runners 1 hr prior to (-1 hr) and at +1 hr, +24 hr, +48 hr, and +72 hr following each exercise session. Time domain indexes and a high frequency component showed a significant decrease…

  6. Simplifying cardiovascular risk estimation using resting heart rate.

    LENUS (Irish Health Repository)

    Cooney, Marie Therese

    2010-09-01

    Elevated resting heart rate (RHR) is a known, independent cardiovascular (CV) risk factor, but is not included in risk estimation systems, including Systematic COronary Risk Evaluation (SCORE). We aimed to derive risk estimation systems including RHR as an extra variable and assess the value of this addition.

  7. Heart Rate Variability Interventions for Concussion and Rehabilitation

    Directory of Open Access Journals (Sweden)

    RobertLakeConder

    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.

  8. Heart rate differences in small sided games in formative basketball

    Directory of Open Access Journals (Sweden)

    Fernando Gracia

    2014-03-01

    Full Text Available The aim of this study was to determine and learn the heart rate responses of basketball players in small-sided or modified games, in order to develop a more effective workout plan in the future. The study sample consisted of 19 basketball players from a National Championship Club, 12 of them in the U’14 category and the remaining 7 belonging to the U’16 category. Small-sided games were 3x3 and 4x4 with a duration of 4 minutes and an active break of 3 minutes. Significant differences (p<0.05 were found referring to the relations established between 3x3 without feedback and 3x3 with feedback in vigorous exercise; in 3x3 without feedback and 3x3 with feedback in moderate exercise; in 3x3 and 3x3 with average heart rate; in 4x4 and 4x4 with average heart rate and in 4x4 and 4x4 with average heart rate related to game categories.Keywords:

  9. Heart rate dynamics in doxorubicin-induced cardiomyopathy.

    Science.gov (United States)

    Lon?ar-Turukalo, T; Vasi?, M; Tasi?, T; Mijatovi?, G; Glumac, S; Baji?, D; Japunži?-Žigon, N

    2015-04-01

    The clinical use of doxorubicin, an effective chemotherapeutic is hampered by the development of irreversible cardiotoxicity. Here we test time-frequency analysis of heart rate (HR) variability (HRV) for early detection of doxorubicin-induced cardiotoxicity. Experiments were conducted in adult male Wistar rats treated for 15 days with doxorubicin (DOXO, total dose 15 mg kg(-1), i.p.) or saline (CONT). DOXO rats exhibited cardiotoxicity confirmed by histological examination without developing heart failure as estimated by echocardiography. However, HR variability increase reflected subtle microscopic changes of cardiac toxicity in DOXO rats. The results recommend time-frequency analysis of HRV for early detection of doxorubicin-induced cardiomyopathy. PMID:25798626

  10. Omega-3 Polyunsaturated Fatty Acids and Heart Rate Variability

    OpenAIRE

    JeppeHagstrupChristensen

    2011-01-01

    Omega-3 polyunsaturated fatty acids (PUFA) may modulate autonomic control of the heart because omega-3 PUFA is abundant in the brain and other nervous tissue as well as in cardiac tissue. This might partly explain why omega-3 PUFA offer some protection against sudden cardiac death (SCD). The autonomic nervous system is involved in the pathogenesis of SCD. Heart rate variability (HRV) can be used as a non-invasive marker of cardiac autonomic control and a low HRV is a predictor for SCD and arr...

  11. Functionality of the baroreceptor nerves in heart rate regulation

    DEFF Research Database (Denmark)

    Ottesen, Johnny T.; Olufsen, Mette

    2011-01-01

    Two models describing the afferent baroreceptor firing are analyzed, a basic model predicting firing using a single nonlinear differential equation, and an extended model, coupling K nonlinear responses. Both models respond to the the rate (derivative) and the rate history of the carotid sinus arterial pressure. As a result both the rate and the relative level of the carotid sinus arterial pressure is sensed. Simulations with these models show that responses to step changes in pressure follow from the rate sensitivity as observed in experimental studies. Adaptation and asymmetric responses 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.

  12. Music structure determines heart rate variability of singers.

    Science.gov (United States)

    Vickhoff, Björn; Malmgren, Helge; Aström, Rickard; Nyberg, Gunnar; Ekström, Seth-Reino; Engwall, Mathias; Snygg, Johan; Nilsson, Michael; Jörnsten, Rebecka

    2013-01-01

    Choir singing is known to promote wellbeing. One reason for this may be that singing demands a slower than normal respiration, which may in turn affect heart activity. Coupling of heart rate variability (HRV) to respiration is called Respiratory sinus arrhythmia (RSA). This coupling has a subjective as well as a biologically soothing effect, and it is beneficial for cardiovascular function. RSA is seen to be more marked during slow-paced breathing and at lower respiration rates (0.1 Hz and below). In this study, we investigate how singing, which is a form of guided breathing, affects HRV and RSA. The study comprises a group of healthy 18 year olds of mixed gender. The subjects are asked to; (1) hum a single tone and breathe whenever they need to; (2) sing a hymn with free, unguided breathing; and (3) sing a slow mantra and breathe solely between phrases. Heart rate (HR) is measured continuously during the study. The study design makes it possible to compare above three levels of song structure. In a separate case study, we examine five individuals performing singing tasks (1-3). We collect data with more advanced equipment, simultaneously recording HR, respiration, skin conductance and finger temperature. We show how song structure, respiration and HR are connected. Unison singing of regular song structures makes the hearts of the singers accelerate and decelerate simultaneously. Implications concerning the effect on wellbeing and health are discussed as well as the question how this inner entrainment may affect perception and behavior. PMID:23847555

  13. Electrocardiogram, heart movement and heart rate in the awake gecko (Hemidactylus mabouia).

    Science.gov (United States)

    Germer, Carina M; Tomaz, Juliana M; Carvalho, Ana F; Bassani, Rosana A; Bassani, José W M

    2015-01-01

    The electrocardiogram (ECG) is the simplest and most effective non-invasive method to assess the electrical activity of the heart and to obtain information on the heart rate (HR) and rhythm. Because information on the HR of very small reptiles (body mass restraint (MR), spontaneous tonic immobility (TI), and in the non-restrained condition (NR). In the gecko ECG, the P, QRS and T waves were clearly distinguishable. The HR was 2.83 ± 0.02 Hz under MR, which was significantly greater (p physical restraint or anesthesia. PMID:25395252

  14. Electron-beam CT coronary angiography in the patients with high heart rate arrhythmia or pacemaker

    International Nuclear Information System (INIS)

    Objective: To report the clinical applicability of coronary angiography for patients with high heart rate, arrhythmia or cardiac pacing using the new-generation of electron-beam CT (e-Speed). Methods: EBCT (GE e-Speed) coronary angiography was performed in 36 eases (male 27, female 9, mean age 58), including the heart rate more than 90 bpm in 20 patients, frequent ectopic beats in 11 cases, implantation of cardiac pacemaker in 4 patients and the unacceptable MSCT image quality due to variability of interscan heart rate (from 82 bpm to 104 bpm) in 1 case. After volume data set was acquired using spiral mode with prospective ECG-gating, the reconstructions of MIP, CPR, VR and Cine were performed. The VR quality was evaluated using a five-point scale. Results: The quality of coronary imaging in all of 36 cases were acceptable. The total visualization rate of coronary artery branches was 80.0%. Left main, left anterior artery and right coronary artery were visualized in all patients and in 94.3% of all cases circumflex artery were visible. Conclusion: EBCT (e-Speed) is applicable in noninvasive coronary angiography for patients with high heart rate, arrhythmia or implanted cardiac pacemaker', and this examination can obtain satisfied diagnosis. (authors)

  15. Peripheral oxygen saturation, heart rate, and blood pressure during dental treatment of children with cyanotic congenital heart disease

    Scientific Electronic Library Online (English)

    Rosane Menezes Faria, Dutra; Itamara Lucia Itagiba, Neves; Ricardo Simões, Neves; Edmar, Atik; Ubiratan de Paula, Santos.

    Full Text Available OBJECTIVES: In this observational study, we evaluated the peripheral oxygen saturation (SpO2), heart rate, and blood pressure of children with cyanotic congenital heart disease who were undergoing dental extraction. METHODS: Forty-four patients between the ages of 6 and 12 years who underwent upp [...] er primary tooth extraction were included in the study. Of these, 20 patients were in the cyanotic congenital heart disease group and 24 were in the control group. RESULTS: Peripheral oxygen saturation, heart rate, and systolic blood pressure in the cyanotic congenital heart disease group varied quite significantly during the treatment protocol (p

  16. HEART RATE AND ACTIVITY PROFILE FOR YOUNG FEMALE SOCCER

    Directory of Open Access Journals (Sweden)

    Granda, J.

    2008-07-01

    Full Text Available The physical and physiological demands of high-level male soccer have been studied extensively, while few studies have investigated the demands placed on females during match-play, however, there is no information available about the heart rate and activity profile of young female soccer players during match play. Therefore, the aim of this study was to examine cardiovascular (heart-rates HR and physical demands of young female soccer players during a match. Players were observed during a friendly competitive match (7-a-side over 2 x 25-min halves. Match activities were assessed with Global Position System technology (1Hz. Result showed that young female soccer players attain 88±4.4% and 86.3±4.8% of HRmax during the first and second half respectively (P=0.3, the average heart rate was 87%. During the first and second half, they covered 2072±197 m and 1905±144 m (P13 km/h resulted lower than that previously reported for age-matched male soccer players and elite female soccer players. This seems to indicate that gender and competitive level differences in match physical performance seem to occur mainly in the absolute match work-rate domain.

  17. Study of foetal heart rate patterns in pregnancy with intra-uterine growth restriction during antepartum period

    International Nuclear Information System (INIS)

    Objectives: To evaluate foetal heart rate pattern during antepartum period in pregnancies suffering from intra-uterine growth restriction. Methods: The case control study was conducted at the Alzahra Hospital, Tabriz, Iran from April 2008 to April 2011. It comprised 100 pregnancies with intra-uterine growth restriction and 92 normal pregnancies. The foetal heart rate pattern including basal heart rate, beat-to-beat variation, non-stress test (NST) result and acceleration and deceleration patterns of the heart rate were determined in both groups during the antepartum period. Findings were compared between the two groups and their relation with pregnancy-foetal outcomes was specified in the case group. SPSS 15 was used for statistical analysis. Results: There was no statistically significant difference between the foetus mean basal heart rate in the two groups (p <0.960). Frequency of cases with non-reactive non-stress test in the Cases was significantly higher than Controls (p <0.005). The difference in heart rate acceleration was also not statistically significant (p <0.618). Frequency of cases with low birth weight and caesarian was non-significantly but borderline higher among the Cases (p <0.081 and 0.060, respectively). Conclusion: Abnormal foetal heart rate pattern is more common in pregnancies marked by intra-uterine growth restriction and is directly associated with worse pregnancy/foetal outcomes. (author)

  18. Noise exposure and children's blood pressure and heart rate: the RANCH project.

    OpenAIRE

    van Kempen, Elise; Kamp, I.; Fischer, P.; Davies, Hugh W.; Houthuijs, D; Stellato, Rebecca K; Clark, Charlotte; Stansfeld, Stephen A.

    2006-01-01

    BACKGROUND: Conclusions that can be drawn from earlier studies on noise and children's blood pressure are limited due to inconsistent results, methodological problems, and the focus on school noise exposure. OBJECTIVES: To investigate the effects of aircraft and road traffic noise exposure on children's blood pressure and heart rate. METHODS: Participants were 1283 children (age 9-11 years) attending 62 primary schools around two European airports. Data were pooled and analysed using multilev...

  19. 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)

    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 examinatiofrom MDCT coronary angiographic examinations.

  20. 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.

  1. Qigong Effects on Heart Rate Variability and Peripheral Vasomotor Responses.

    Science.gov (United States)

    Chang, Mei-Ying

    2014-05-27

    Population aging is occurring worldwide, and preventing cardiovascular event in older people is a unique challenge. The aim of this study was to examine the effects of a 12-week qigong (eight-form moving meditation) training program on the heart rate variability and peripheral vasomotor response of middle-aged and elderly people in the community. This was a quasi-experimental study that included the pre-test, post-test, and nonequivalent control group designs. Seventy-seven participants (experimental group = 47; control group = 30) were recruited. The experimental group performed 30 min of eight-form moving meditation 3 times per week for 12 weeks, and the control group continued their normal daily activities. After 12 weeks, the interaction effects indicated that compared with the control group, the experimental group exhibited significantly improved heart rate variability and peripheral vasomotor responses. PMID:24869492

  2. Low Cost Heart Rate Monitor Using Led-Led Sensor

    Directory of Open Access Journals (Sweden)

    Ahmed Mahrous Ragib

    2009-01-01

    Full Text Available A high sensitivity, low power and low cost sensor has been developed for photoplethysmography (PPG measurement. The PPG principle was applied to follow the dilatation and contraction of skin blood vessels during the cardiac cycle. A standard light emitting diodes (LEDs has been used as a light emitter and detector, and in order to reduce the space, cost and power, the classical analogue-to-digital converters (ADCs replaced by the pulse-based signal conversion techniques. A general purpose microcontroller has been used for the implementation of measurement protocol. The proposed approach leads to better spectral sensitivity, increased resolution, reduction in cost, dimensions and power consumption. The basic sensing configuration presented is capable of detecting the PPG signal from a finger or toe, and it is very simple to extract the heart rate and heart rate variability from such a signal.

  3. Effect of mobile phone radiation on heart rate variability.

    Science.gov (United States)

    Ahamed, V I Thajudin; Karthick, N G; Joseph, Paul K

    2008-06-01

    The rapid increase in the use of mobile phones (MPs) in recent years has raised the problem of health risk connected with high-frequency electromagnetic fields. There are reports of headache, dizziness, numbness in the thigh, and heaviness in the chest among MP users. This paper deals with the neurological effect of electromagnetic fields radiated from MPs, by studies on heart rate variability (HRV) of 14 male volunteers. As heart rate is modulated by the autonomic nervous system, study of HRV can be used for assessing the neurological effect. The parameters used in this study for quantifying the effect on HRV are scaling exponent and sample entropy. The result indicates an increase in both the parameters when MP is kept close to the chest and a decrease when kept close to the head. MP has caused changes in HRV indices and the change varied with its position, but the changes cannot be considered significant as the p values are high. PMID:18486937

  4. Heart Rate Variability in Patients with Rheumatoid Arthritis

    OpenAIRE

    Kawser Jahan, Noorzahan Begum, Sultana Ferdousi

    2012-01-01

    Background: Altered cardiovascular autonomic nerve function with impaired sympathovagal balance is found in rheumatoid arthritis (RA). Heart Rate Variability (HRV) analysis is an important tool for assessment of autonomic nerve activity.Objective: To assess cardiac autonomic nerve function status in patients with Rheumatoid arthritis (RA) by time domain measures of HRV.Methods: This cross sectional study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical Universit...

  5. Heart rate control in hypertensive patients treated by captopril.

    OpenAIRE

    Sturani, A; Chiarini, C; Degliesposti, E; Santoro, A; Zuccalà, A; Zucchelli, P.

    1982-01-01

    1 The effect of captopril on autonomic reflex functions has been investigated in fifteen patients with essential hypertension by examining their responses to tests of baroreceptor function (Valsalva's manoeuvre and upright posture), sympathetic nervous system reactivity (cold pressor and mental stress tests) and parasympathetic reactivity (diving test) before and after 3 weeks' treatment with captopril. 2 Captopril significantly reduced arterial blood pressure and resting heart rate but did n...

  6. Heart Rate Variability Analysis in Patients with Allergic Rhinitis

    OpenAIRE

    Ming-Ying Lan; Guo-She Lee; An-Suey Shiao; Jen-Hung Ko; Chih-Hung Shu

    2013-01-01

    Background. Very few studies investigate the role of the autonomic nervous system in allergic rhinitis. In this study, we evaluated the autonomic nervous system in allergic rhinitis patients using heart rate variability (HRV) analysis. Methods. Eleven patients with allergic rhinitis and 13 healthy controls, aged between 19 and 40 years old, were enrolled in the study. Diagnosis of allergic rhinitis was based on clinical history, symptoms, and positive Phadiatop test. Electrocardiographic reco...

  7. Association between oral variables and heart rate variability

    OpenAIRE

    Santana, Milana Drumond Ramos; Souza, Ana Cecilia Amorim; Abreu, Luiz Carlos; Valenti, Vitor E.

    2013-01-01

    The heart rate variability is a useful method to assess cardiac autonomic modulation in patients undergoing dental procedures, because knowledge of physiological conditions provides greater security to the professional as well as the possibility of a better plan treatment to patient benefit. The aim of our study was to describe the association between cardiac autonomic control and dental variables. We consulted the databases Medline, SciELO, Lilacs and Cochrane, using the terms “autonomic?...

  8. Foetal heart rate recording: analysis and comparison of different methodologies

    OpenAIRE

    Ruffo, Mariano

    2011-01-01

    Monitoring foetal health is a very important task in clinical practice to appropriately plan pregnancy management and delivery. In the third trimester of pregnancy, ultrasound cardiotocography is the most employed diagnostic technique: foetal heart rate and uterine contractions signals are simultaneously recorded and analysed in order to ascertain foetal health. Because ultrasound cardiotocography interpretation still lacks of complete reliability, new parameters and methods of interpreta...

  9. Elevated resting heart rate is associated with the metabolic syndrome

    OpenAIRE

    Saar Nili; Cohen Michael; Berliner Shlomo; Steinvil Arie; Rogowski Ori; Kliuk Ben-Bassat Orit; Shapira Itzhak

    2009-01-01

    Abstract Background Increased resting heart rate (RHR) may be associated with increased cardiovascular morbidity. Our aim was to explore the possibility that increased RHR is associated with the prevalence of the metabolic syndrome (MetS) in a sample of apparently healthy individuals and those with cardiovascular risk factors. Methods We performed a cross-sectional analysis in a large sample of apparently healthy individuals who attended a general health screening program and agreed to partic...

  10. 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...

  11. Aging Affects the Response of Heart Rate Variability Autonomic Indices to Atropine and Isoproteronol

    Directory of Open Access Journals (Sweden)

    Kenneth M. Madden

    2008-01-01

    Full Text Available Background: Normalized ratios of portions of the power frequency spectrum of heart rate (HR are commonly used to gain insight into cardiac “sympathovagal balance.” Whether aging, which alters both sympathtetic and parasympathetic activities, infl uences these measures has not been well characterized.Objectives: We examined the ability of normalized ratios of the power frequency spectrum of heart rate to describe autonomic activity at the sinus node in older and younger adults during conditions of sympathetic predominance.Methods: 20 older (mean age 70.0 ± 1.5 years and 24 younger (mean age 25.4 ± 0.9 years normal adults were screened by history, physical examination, blood work (CBC, electrolytes, creatinine, liver function tests, ECG, exercise tolerance test, echocardiogram and myocardial perfusion scan (if 65 years old. A 2-channel Holter was used to monitor heart rate. Total (TP, low frequency (LF and high frequency power (HF were obtained by Fast Fourier Transform. Intravenous atropine (2 boluses of 0.01 mg/kg was followed by isoproterenol infusions of 7 and 21 ng/kg/min to tilt the “sympathovagal balance” to the sympathetic nervous system side.Results: Normalized HF power gave expected results in response to atropine only in younger subjects. Changes in normalized LF power had a much stronger correlation with changes in heart rate in older as opposed to younger subjects.Conclusions: The response of normalized power ratios to atropine and isoproterenol varies between different age groups.

  12. Autonomic contribution to heart rate recovery from exercise in humans.

    Science.gov (United States)

    Savin, W M; Davidson, D M; Haskell, W L

    1982-12-01

    To assess the contribution of the autonomic nervous system to heart rate recovery following exertion, heart rate was observed after peak treadmill exercise in six men following parasympathetic blockade (PB) with atropine sulfate (0.03 mg/kg), sympathetic blockade (SB) with propranolol hydrochloride (0.20 mg/kg), double blockade (DB) with both drugs, and no drugs (ND). Least-squares analysis of each subject's heart rate (HR) as an exponential function of recovery time (t) was computed for each treatment giving an equation of the form HR = aebt. HRs at rest, peak exercise, and 10 min of recovery, the coefficients a and b, and the least-squares correlation coefficient (r) were compared among treatments by nonparametric analysis of variance and rank-sum multiple comparisons. HR recovered in an exponential manner after dynamic exercise in each subject with each of the treatment modes (P less than 0.01 for each r, mean across all treatments r = 0.94). Coefficients a and b differed the most between PB and SB. At the cessation of exercise the decreases in venous return and the systemic need for cardiac output are accompanied by an exponential HR decline. The exponential character of the cardiodeceleration seen after peak exercise appears to be an intrinsic property of the circulation because it occurred under each experimental condition. PMID:7153152

  13. Design and development of a heart rate variability analyzer.

    Science.gov (United States)

    Mohan, Aparna; James, Frana; Fazil, Sajeer; Joseph, Paul K

    2012-06-01

    Heart rate variability (HRV), analysis gives an insight into the state of the autonomic nervous system which modulates the cardiac activity. Here a digital signal controller based handy device is developed which acquires the beat to beat time interval, processes it using techniques based on non-linear dynamics, fractal time series analysis, and information theory. The technique employed, that can give reliable results by assessing heart beat signals fetched for a duration of a few minutes, is a huge advantage over the already existing methodologies of assessing cardiac health, those being dependant on the tedious task of acquiring Electro Cardio Gram(ECG) signals, which in turn requires the subject to lie down at a stretch for a couple of hours. The sensor used, relies on the technique of Photoplethysmography, rendering the whole approach as noninvasive. The device designed, calculates parameters like, Largest Lyapunov Exponent, Fractal dimension, Correlation Dimension, Approximate Entropy and ?-slope of Poincare plots, which based on the range in which they fall, the cardiac health condition of the subject can be assessed to even the extend of predicting upcoming disorders. The design of heart beat sensor, the technique used in the acquisition of heart beat data, the relevant algorithm developed for the analysis purpose, are presented here. PMID:21057888

  14. Blood pressure and heart rate in patients with ischaemic heart disease receiving nifedipine and propranolol.

    OpenAIRE

    Harris, L.; Dargie, H. J.; Lynch, P. G.; Bulpitt, C J; Krikler, D M

    1982-01-01

    A randomised controlled crossover trial was performed to assess the anti-anginal effects of nifedipine and propranolol separately and together. The effects of these treatments on blood pressure and heart rate were assessed at rest and after the cold pressor and mental arithmetic tests. Nifedipine and propranolol together produced the greatest reduction in supine and erect systolic and diastolic blood pressures. Propranolol (480 mg daily) lowered resting systolic/diastolic blood pressures by 7...

  15. A Polymorphism in the ?1 Adrenergic Receptor Is Associated with Resting Heart Rate

    OpenAIRE

    Ranade, Koustubh; Jorgenson, Eric; Sheu, Wayne H. -h; Pei, Dee; Hsiung, Chao Agnes; Chiang, Fu-tien; Chen, Yii-der I.; Pratt, Richard; Olshen, Richard A.; Curb, David; Cox, David R.; Botstein, David; Risch, Neil

    2002-01-01

    Resting heart rate is significantly associated with cardiovascular morbidity and mortality. However, the extent to which resting heart rate is genetically determined is poorly understood, and no genes have been found that contribute to variation in resting heart rate. Because signaling through the ?1 adrenergic receptor is a key determinant of cardiac function, we tested whether polymorphisms in this receptor are associated with resting heart rate. A cohort of >1,000 individuals of Chinese a...

  16. Resting heart rate: A modifiable prognostic indicator of cardiovascular risk and outcomes?

    OpenAIRE

    Arnold, J. Malcolm; Fitchett, David H.; Howlett, Jonathan G.; Lonn, Eva M.; Tardif, Jean-claude

    2008-01-01

    A growing body of evidence from clinical trials and epidemiological studies has identified elevated resting heart rate as a predictor of clinical events. Proof of direct cause and effect is limited, because current drugs that lower heart rate (eg, beta-blockers) have multiple mechanisms of action. A new class of drug, selective If inhibitors, is under investigation as a ‘pure’ heart rate-reducing medication and will help confirm if there is a causal link between elevated heart rate and ca...

  17. Association between the Rating Perceived Exertion, Heart Rate and Blood Lactate in Successive Judo Fights (Randori

    Directory of Open Access Journals (Sweden)

    Braulio Henrique Magnani Branco

    2013-06-01

    Full Text Available Purpose: This study aims to investigate the association between the rating of perceived exertion (RPE, heart rate (HR and the blood lactate concentration ([La] in successive judo fight simulations (randori.Methods: Ten athletes participated in the study (age: 25.6±2.1 years; stature: 1.75±0.07 m; body mass: 75.6±14.9kg; %BF: 11.5±7.8%; practice: 14.5±6.2 years and completed 4 judo fight simulations (T1 to T4 with duration of 5 min separated by 5 min passive recovery periods. Before each randori, [La] and HR were collected, and after each randori, the same measures and the RPE (CR-10 scale were collected.Results: Significant correlations were observed between: (1 CR-10 and HR (T2: r =0.70; T3: r =0.64; both, P<0.05; (2 ?CR-10 and ?[La] (T1-T2: r = .71, P< 0.05; T2-T3: r =0.92, P<0.01; T3-T4: r =0.73, P<0.05. Moreover, significant differences were noted in the behavior of the HR between the 2nd (T2 and 3rd (T3 judo fight simulations (P<0.05.Conclusion: The use of CR-10 in the evaluation process, as well as in deciding the load of training in judo, should be done with caution

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

    DEFF Research Database (Denmark)

    den Hoed, Marcel; Eijgelsheim, Mark

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology 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 with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identifynew therapeutic targets.

  19. Heart Rates of High School Physical Education Students during Team Sports, Individual Sports, and Fitness Activities

    Science.gov (United States)

    Laurson, Kelly R.; Brown, Dale D.; Cullen, Robert W.; Dennis, Karen K.

    2008-01-01

    This study examined how activity type influenced heart rates and time spent in target heart rate zones of high school students participating in physical education classes. Significantly higher average heart rates existed for fitness (142 plus or minus 24 beats per minute [bpm]) compared to team (118 plus or minus 24 bpm) or individual (114 plus or…

  20. The Relationship between Heart Rate Reserve and Oxygen Uptake Reserve in Children and Adolescents

    Science.gov (United States)

    Hui, Stanley Sai-chuen; Chan, Janus Wan-sze

    2006-01-01

    The purpose of the present study was to examine the relationship between oxygen uptake (VO[subscript 2]) and heart rate (HR) responses during rest and exercise in Chinese children and youth and to evaluate the relationships between maximal heart rate (%HRmax), heart rate reserve (%HRR), peak oxygen uptake (%VO[subscript 2]peak), and oxygen uptake…

  1. Problem Behavior and Heart Rate Reactivity in Adopted Adolescents: Longitudinal and Concurrent Relations

    Science.gov (United States)

    Bimmel, Nicole; van IJzendoorn, Marinus H.; Bakermans-Kranenburg, Marian J.; Juffer, Femmie; De Geus, Eco J. C.

    2008-01-01

    The present longitudinal study examined resting heart rate and heart rate variability and reactivity to a stressful gambling task in adopted adolescents with aggressive, delinquent, or internalizing behavior problems and adopted adolescents without behavior problems (total N=151). Early-onset delinquent adolescents showed heart rate

  2. Making the Most of the "Daphnia" Heart Rate Lab: Optimizing the Use of Ethanol, Nicotine & Caffeine

    Science.gov (United States)

    Corotto, Frank; Ceballos, Darrel; Lee, Adam; Vinson, Lindsey

    2010-01-01

    Students commonly test the effects of chemical agents on the heart rate of the crustacean "Daphnia" magna, but the procedure has never been optimized. We determined the effects of three concentrations of ethanol, nicotine, and caffeine and of a control solution on heart rate in "Daphnia." Ethanol at 5% and 10% (v/v) reduced mean heart rate to…

  3. Blue 405 nm laser light mediates heart rate – investigations at the acupoint Neiguan (Pe.6 in Chinese adults

    Directory of Open Access Journals (Sweden)

    Gerhard Litscher

    2009-10-01

    Full Text Available Background: In previous studies, we showed that laser needle acupuncture with red and infrared light has specific effects on bio-signals of the brain and heart. Aims: In this publication we report the effect of blue laser light on heart rate and heart rate variability (HRV before, during and after acupuncture at the acupoint Neiguan (Pe.6 in Chinese adults. These are the first data published concerning heart rate and HRV, obtained with blue laser acupuncture equipment. Patients and Methods: The investigations were carried out in 13 healthy Chinese volunteers with a mean age of 31.2 ± 7.5 years within a randomized, controlled study. Stimulation was performed with painless blue laser light (wavelength: 405 nm; activation: 10 minutes bilaterally at Pe.6. In a second session, for control reasons the laser was not activated. Results Heart rate showed a significant (p=0.008 decrease during blue laser light stimulation. In contrast, no significant changes were found when the laser was deactivated. The evaluation parameter LF/HF ratio (low frequency/high frequency ratio from the HRV spectral analysis showed a very slight increase during stimulation, however it was not significant. Conclusions: Our main conclusion is that continuous blue laser light stimulation on Neiguan significantly reduces heart rate of Chinese adults.

  4. Heritability of cardiac vagal control in 24-h heart rate variability recordings: influence of ceiling effects at low heart rates.

    Science.gov (United States)

    Neijts, Melanie; Van Lien, Rene; Kupper, Nina; Boomsma, Dorret; Willemsen, Gonneke; de Geus, Eco J C

    2014-10-01

    This study estimated the heritability of 24-h heart rate variability (HRV) measures, while considering ceiling effects on HRV at low heart rates during the night. HRV was indexed by the standard deviation of all valid interbeat intervals (SDNN), the root mean square of differences between valid, successive interbeat intervals (RMSSD), and peak-valley respiratory sinus arrhythmia (pvRSA). Sleep and waking levels of cardiac vagal control were assessed in 1,003 twins and 285 of their non-twin siblings. Comparable heritability estimates were found for SDNN (46%-53%), RMSSD (49%-54%), and pvRSA (48%-57%) during the day and night. A nighttime ceiling effect was revealed in 10.7% of participants by a quadratic relationship between mean pvRSA and the interbeat interval. Excluding these participants did not change the heritability estimates. The genetic factors influencing ambulatory pvRSA, RMSSD, and SDNN largely overlap. These results suggest that gene-finding studies may pool the different cardiac vagal indices and that exclusion of participants with low heart rates is not required. PMID:24894483

  5. Impact of caffeine on heart rate and blood pressure at rest and during exercise

    Directory of Open Access Journals (Sweden)

    Azam Mousavi

    2011-05-01

    Full Text Available Introduction:Several studies have evaluated the impact of caffeine consumption on athletes performance from different aspects; however, the findings are varied. The aim of this research was to evaluate the impact of caffeine consumption on some of the cardiovascular factors including heart rate and blood pressure at rest, at the end of exercise, and during the 3rd and 5th minutes of recovery. Material and Methods:The subjects of this study included 20 female athletes, voluntarily participating in the study. Two separate tests with an interval of one week were conducted. The subjects received placebo for the first test and caffeine containing capsules (5 mg/kg for the second test. The patient heart rate and blood pressure were measured at rest, at the end of the exercise and during the 3rd and 5th minutes of recovery after submaximal test. Maximal oxygen consumption (VO2max was measured using Fax submaximal cardiorespiratory test. Paired t- test was used for data analysis. Results:Caffeine consumption had no significantly effect on VO2max, resting and end exercise heart rate, and blood pressure recorded at the end of the exercise. Caffeine consumption caused a significant increase in the heart rate during 3rd and 5th minutes of recovery, and in blood pressure at rest, and during the 3rd and the 5th minutes of recovery in the athletes. Conclusion:Due to the caffeine induced increase in blood pressure and heart rate, caffeine consumption (5 mg/kg before submaximal exercise is not recommended either for those who suffer hypertension or cardiac disease nor for those who do exercise for health or athletic purposes.

  6. A Comparison of Verapamil and Digoxin for Heart Rate Control in Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Mohammad Afzali Moghadam

    2012-08-01

    Full Text Available Purpose: Atrial fibrillation (AF is one of the most common types of sustained dysrhythmia and there are some disagreements about its treatment. The goals of AF treatment include the control of ventricular rate, the establishment of sinus rhythm and the prevention of thromboembolic events. In this study, the effect of verapamil was compared to digoxin on heart rate control in patients with AF. Methods:This descriptive study was conducted in an emergency department (ED in Iran. Sixty patients with a new onset AF and rapid ventricular response receiving digoxin or verapamil were included and observed. Results:Two thirty-patient groups receiving verapamil or digoxin were evaluated. The heart rate was significantly decreased in both groups (p = 0.002; however, the cardioversion was not noticed in both of them. The best rate control in verapamil and digoxin groups was observed after 5.9 mg (46.7% and 0.6 mg (36.7%, respectively. Conclusion: Administration of verapamil in comparison with digoxin has no difference to control the heart rate in AF patients. It should be taken into consideration that prospective randomized studies should be conducted to identify the efficacy and select the best of these two drugs to treat AF patients.

  7. Heart rate and respiratory rhythm dynamics on ascent to high altitude.

    OpenAIRE

    Lipsitz, L. A.; Hashimoto, F.; Lubowsky, L. P.; Mietus, J.; Moody, G. B.; Appenzeller, O.; Goldberger, A. L.

    1995-01-01

    OBJECTIVE--To investigate the alterations in autonomic control of heart rate at high altitude and to test the hypothesis that hypoxaemic stress during exposure to high altitude induces non-linear, periodic heart rate oscillations, similar to those seen in heart failure and the sleep apnoea syndrome. SUBJECTS--11 healthy subjects aged 24-64. MAIN OUTCOME MEASURES--24 hour ambulatory electrocardiogram records obtained at baseline (1524 m) and at 4700 m. Simultaneous heart rate and respiratory d...

  8. The predictive value of resting heart rate following osmotherapy in brain injury: back to basics

    OpenAIRE

    Mahsa Hasanpour Mir; Fardin Yousefshahi; Mohammad Abdollahi,; Arezoo Ahmadi; Atabak Nadjafi; Mojtaba Mojtahedzadeh

    2012-01-01

    Abstract Background The importance of resting heart rate as a prognostic factor was described in several studies. An elevated heart rate is an independent risk factor for adverse cardiovascular events and total mortality in patients with coronary artery disease, chronic heart failure, and the general population. Also heart rate is elevated in the Multi Organ Dysfunction Syndrome (MODS) and the mortality due to MODS is highly correlated with inadequate sinus tachycardia. To evaluate the value ...

  9. Heart rate variability and metabolic rate in healthy young adults with low birth weight

    OpenAIRE

    Weitz, Gunther; Bonnemeier, Hendrik; Su?fke, Sven; Wellho?ner, Peter; Lehnert, Hendrik; Dodt, Christoph

    2013-01-01

    Objective: Low birth weight (LBW) is associated with obesity and a higher cardiovascular risk in adult life. Since autonomic dysfunction could be a pathophysiological factor for this association, we assessed the impact of LBW on cardiac autonomic activity and metabolic rate in young adulthood. We hypothesized that the autonomic tone could be coupled with the metabolic rate in subjects with LBW. Methods: Heart rate variability (HRV) from 24-hour Holter-electrocardiograms was measured in 15 hea...

  10. Omega-3 Polyunsaturated Fatty Acids and Heart Rate Variability

    DEFF Research Database (Denmark)

    Christensen, Jeppe Hagstrup

    2011-01-01

    Omega-3 polyunsaturated fatty acids (PUFA) may modulate autonomic control of the heart because omega-3 PUFA is abundant in the brain and other nervous tissue as well as in cardiac tissue. This might partly explain why omega-3 PUFA offer some protection against sudden cardiac death (SCD). The autonomic nervous system is involved in the pathogenesis of SCD. Heart rate variability (HRV) can be used as a non-invasive marker of cardiac autonomic control and a low HRV is a predictor for SCD and arrhythmic events. Studies on HRV and omega-3 PUFA have been performed in several populations such as patients with ischemic heart disease, patients with diabetes mellitus, patients with chronic renal failure, and in healthy subjects as well as in children. The studies have demonstrated a positive association between cellular content of omega-3 PUFA and HRV and supplementation with omega-3 PUFA seems to increase HRV which could be a possible explanation for decreased risk of arrhythmic events and SCD sometimes observed afteromega-3 PUFA supplementation. However, the results are not consistent and further research is needed.

  11. Changes in deceleration capacity of heart rate and heart rate variability induced by ambient air pollution in individuals with coronary artery disease

    Directory of Open Access Journals (Sweden)

    Oberdörster Günter

    2010-10-01

    Full Text Available Abstract Background and Objective Exposure to ambient particles has been shown to be responsible for cardiovascular effects, especially in elderly with cardiovascular disease. The study assessed the association between deceleration capacity (DC as well as heart rate variability (HRV and ambient particulate matter (PM in patients with coronary artery disease (CAD. Methods A prospective study with up to 12 repeated measurements was conducted in Erfurt, Germany, between October 2000 and April 2001 in 56 patients with physician-diagnosed ischemic heart disease, stable angina pectoris or prior myocardial infarction at an age of at least 50 years. Twenty-minute ECG recordings were obtained every two weeks and 24-hour ECG recordings every four weeks. Exposure to PM (size range from 10 nm to 2.5 ?m, and elemental (EC and organic (OC carbon was measured. Additive mixed models were used to analyze the association between PM and ECG recordings. Results The short-term recordings showed decrements in the high-frequency component of HRV as well as in RMSSD (root-mean-square of successive differences of NN intervals in association with increments in EC and OC 0-23 hours prior to the recordings. The long-term recordings revealed decreased RMSSD and pNN50 (% of adjacent NN intervals that differed more than 50 ms in association with EC and OC 24-47 hours prior to the recordings. In addition, highly significant effects were found for DC which decreased in association with PM2.5, EC and OC concurrent with the ECG recordings as well as with a lag of up to 47 hours. Conclusions The analysis showed significant effects of ambient particulate air pollution on DC and HRV parameters reflecting parasympathetic modulation of the heart in patients with CAD. An air pollution-related decrease in parasympathetic tone as well as impaired heart rate deceleration capacity may contribute to an increased risk for cardiac morbidity and sudden cardiac death in vulnerable populations.

  12. Resting heart rate: risk indicator and emerging risk factor in cardiovascular disease.

    Science.gov (United States)

    Böhm, Michael; Reil, Jan-Christian; Deedwania, Prakash; Kim, Jae B; Borer, Jeffrey S

    2015-03-01

    Resting heart rate is central to cardiac output and is influenced by changes occurring in numerous diseases. It predicts longevity and cardiovascular diseases, and current evidence suggests that it is also an important marker of outcome in cardiovascular disease, including heart failure. Beta-blockers improve outcomes in heart failure; however, they have effects outside reducing heart rate. Ivabradine has demonstrated efficacy in reducing rehospitalizations and mortality in heart failure and in improving exercise tolerance and reducing angina attacks in patients with coronary artery disease, whereas selective heart rate reduction may also prove to be beneficial in therapeutic areas outside those in which ivabradine has already demonstrated clinical efficacy. This review provides an update on the associations between heart rate and cardiovascular outcomes in various conditions, the experimental effects of heart rate reduction with ivabradine, and the potential new indications in cardiovascular disease. PMID:25447617

  13. The slope of the oxygen pulse curve does not depend on the maximal heart rate in elite soccer players

    Science.gov (United States)

    Perim, Raphael Rodrigues; Signorelli, Gabriel Ruiz; Myers, Jonathan; Arena, Ross; de Araújo, Claudio Gil Soares

    2011-01-01

    INTRODUCTION: It is unknown whether an extremely high heart rate can affect oxygen pulse profile during progressive maximal exercise in healthy subjects. OBJECTIVE: Our aim was to compare relative oxygen pulse (adjusted for body weight) curves in athletes at their maximal heart rate during treadmill cardiopulmonary exercise testing. METHODS: A total of 180 elite soccer players were categorized in quartiles according to their maximum heart rate values (n ?=? 45). Oxygen consumption, maximum heart rate and relative oxygen pulse curves in the extreme quartiles, Q1 and Q4, were compared at intervals corresponding to 10% of the total duration of a cardiopulmonary exercise testing. RESULTS: Oxygen consumption was similar among all subjects during cardiopulmonary exercise testing; however subjects in Q1 started to exhibit lower maximum heart rate values when 20% of the test was complete. Conversely, the relative oxygen pulse was higher in this group when cardiopulmonary exercise testing was 40% complete (p<.01). Although the slopes of the lines were similar (p?=?.25), the regression intercepts differed (p<.01) between Q1 and Q4. During the last two minutes of testing, a flat or decreasing oxygen pulse was identified in 20% of the soccer players, and this trend was similar between subjects in Q1 and Q4. CONCLUSION: Relative oxygen pulse curve slopes, which serve as an indirect and non-invasive surrogate for stroke volume, suggest that the stroke volume is similar in young and aerobically fit subjects regardless of the maximum heart rate reached. PMID:21789388

  14. The slope of the oxygen pulse curve does not depend on the maximal heart rate in elite soccer players

    Directory of Open Access Journals (Sweden)

    Raphael Rodrigues Perim

    2011-01-01

    Full Text Available INTRODUCTION: It is unknown whether an extremely high heart rate can affect oxygen pulse profile during progressive maximal exercise in healthy subjects. OBJECTIVE: Our aim was to compare relative oxygen pulse (adjusted for body weight curves in athletes at their maximal heart rate during treadmill cardiopulmonary exercise testing. METHODS: A total of 180 elite soccer players were categorized in quartiles according to their maximum heart rate values (n = 45. Oxygen consumption, maximum heart rate and relative oxygen pulse curves in the extreme quartiles, Q1 and Q4, were compared at intervals corresponding to 10% of the total duration of a cardiopulmonary exercise testing. RESULTS: Oxygen consumption was similar among all subjects during cardiopulmonary exercise testing; however subjects in Q1 started to exhibit lower maximum heart rate values when 20% of the test was complete. Conversely, the relative oxygen pulse was higher in this group when cardiopulmonary exercise testing was 40% complete (p<.01. Although the slopes of the lines were similar (p = .25, the regression intercepts differed (p<.01 between Q1 and Q4. During the last two minutes of testing, a flat or decreasing oxygen pulse was identified in 20% of the soccer players, and this trend was similar between subjects in Q1 and Q4. CONCLUSION: Relative oxygen pulse curve slopes, which serve as an indirect and non-invasive surrogate for stroke volume, suggest that the stroke volume is similar in young and aerobically fit subjects regardless of the maximum heart rate reached.

  15. Heart rate response to hypoxic exercise : role of dopamine D2-receptors and effect of oxygen supplementation

    DEFF Research Database (Denmark)

    Lundby, C; MØller, P

    2001-01-01

    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 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 breathing completely reversed the decrease in maximal heart rate to values not different from those at sea level. In conclusion, dopamine D(2)-receptor blockade with domperidone demonstrates that hypoxic exercise in humans activates D(2)-receptors, resulting in a decrease in circulating levels of noradrenaline. However, dopamine D(2)-receptors are not involved in the hypoxia-induced decrease in the maximal heart rate. These data suggest that receptor uncoupling, and not down-regulation, of cardiac adrenoreceptors, is responsible for the early decrease in heart rate at maximal hypoxic exercise.

  16. Heart rate and estimated energy expenditure during ballroom dancing.

    Science.gov (United States)

    Blanksby, B A; Reidy, P W

    1988-06-01

    Ten competitive ballroom dance couples performed simulated competitive sequences of Modern and Latin American dance. Heart rate was telemetered during the dance sequences and related to direct measures of oxygen uptake and heart rate obtained while walking on a treadmill. Linear regression was employed to estimate gross and net energy expenditures of the dance sequences. A multivariate analysis of variance with repeated measures on the dance factor was applied to the data to test for interaction and main effects on the sex and dance factors. Overall mean heart rate values for the Modern dance sequence were 170 beats.min-1 and 173 beats.min-1 for males and females respectively. During the Latin American sequence mean overall heart rate for males was 168 beats.min-1 and 177 beats.min-1 for females. Predicted mean gross values of oxygen consumption for the males were 42.8 +/- 5.7 ml.kg-1 min-1 and 42.8 +/- 6.9 ml.kg-1 min-1 for the Modern and Latin American sequences respectively. Corresponding gross estimates of oxygen consumption for the females were 34.7 +/- 3.8 ml.kg-1 min-1 and 36.1 +/- 4.1 ml.kg-1 min-1. Males were estimated to expand 54.1 +/- 8.1 kJ.min-1 of energy during the Modern sequence and 54.0 +/- 9.6 kJ.min-1 during the Latin American sequence, while predicted energy expenditure for females was 34.7 +/- 3.8 kJ.min-1 and 36.1 +/- 4.1 kJ.min-1 for Modern and Latin American dance respectively. The results suggested that both males and females were dancing at greater than 80% of their maximum oxygen consumption. A significant difference between males and females was observed for predicted gross and net values of oxygen consumption (in L.min-1 and ml.kg-1 min-1). PMID:3167503

  17. Heart rate variability biofeedback: How and why does it work?

    Directory of Open Access Journals (Sweden)

    PaulMLehrer

    2014-07-01

    Full Text Available In recent years there has been substantial support for Heart Rate Variability Biofeedback (HRVB as a treatment for a variety of disorders and for performance enhancement (Gevirtz, 2013. Since conditions as widely varied as asthma and depression seem to respond to this form of cardiorespiratory feedback training, the issue of possible mechanisms becomes more salient. The most supported possible mechanism is the strengthening of homeostasis in the barorecptor (Vashillo, et al, 2002; Lehrer, et al, 2003. Recently, the effect on the vagal afferent pathway to the frontal cortical areas has been proposed. In this article, we review these and other possible mechanisms that might explain the positive effects of HRVB.

  18. Effect of Wireless Network Radiation on Heart Rate Variability

    OpenAIRE

    Barjinder Singh Saini; Anukul Pandey

    2014-01-01

    The health risk associated with the increased exposure to wireless network devices like Mobile Phones, Wi-Fi etc, had been area of concern. In this paper, the effects of wireless network radiations (WNR) on Heart Rate Variability (HRV) had been investigated. The two non-linear indices namely i) Approximate Entropy (ApEn) ii) Detrended Fluctuation Analysis (DFA) had been used for deciphering the hidden dynamics of HRV. The study comprised of 19 healthy male subjects in the age group of 23±4.3...

  19. Determinants for Heart Rate Variability in a Normal Korean Population

    OpenAIRE

    Kim, Gyung-Mee; Woo, Jong-Min

    2011-01-01

    This study examined the normal ranges and the determinants for various parameters of the short-term heart rate variability (HRV) measurements in a large Korean sample of healthy people. HRV measurements were obtained in 2,748 healthy men and 735 healthy women 18-65 yr of age. The mean total power (TP), low frequency (LF), high frequency (HF), and LF/HF ratio were 1,358.9 ± 1,840.8 ms2, 417.3 ± 807.6 ms2, 254.1 ± 414.1 ms2, and 2.4 ± 20.9 ms2 in the frequency-domain spectral analysis. The ...

  20. Long-term mortality risk in patients with an implantable cardioverter-defibrillator : Influence of heart rate and QRS duration

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Theuns, Dominic A M J

    2014-01-01

    BACKGROUND: A paucity of studies has investigated the role of autonomic cardiac regulation as well as cardiac conduction in relation to prognosis in implantable cardioverter-defibrillator (ICD) patients. Therefore, we examined the association of heart rate and QRS duration with long-term mortality risk in first-time ICD patients, adjusting also for measures of emotional distress. METHODS: Resting heart rate and QRS duration were assessed prior to ICD implantation in 448 patients. Primary study endpoint was all-cause mortality (up to 6.0 year follow-up, median follow-up of 5.6 years (IQR: 1.9)). The impact of heart rate and QRS duration on time to all-cause mortality was separately assessed with Cox proportional hazard regression analysis, adjusting for clinical factors and symptoms of depression and anxiety. RESULTS: Mean (SD) heart rate was 68.0 ± 13.3 bpm and mean QRS duration was 130.9 ± 36.9 ms. Heart rate of ?80 bpm was associated with increased risk of mortality (HR=1.86; 95% CI=1.15-3.00; p=.011) in unadjusted analysis. In adjusted analyses, this relationship remained significant both with depression (HR=1.86, 95% CI=1.12-3.09; p=.017) and anxiety (HR=1.82, 95% CI=1.10-3.03; p=.021) and clinical measures as covariates. QRS duration of ?120 ms was associated with impaired prognosis in unadjusted analysis (HR=2.00, 95% CI=1.27-3.14; p=.003), but was reduced to non-significance in adjusted analysis when medical comorbidities were included (HR=1.15, 95% CI=0.70-1.89; p=.60). CONCLUSIONS: This study shows that increased heart rate is associated with impaired prognosis. Since heart rate is a relatively easy measurable parameter of autonomic functioning, heart rate should be included as a measure for risk stratification in daily clinical practice.

  1. Impact of heart rate and rhythm on radiation exposure in prospectively ECG triggered computed tomography

    International Nuclear Information System (INIS)

    Purpose: To evaluate the influence of different heart rates and arrhythmias on scanner performance, image acquisition and applied radiation exposure in prospectively ECG triggered computed tomography (pCT). Materials and methods: An ECG simulator (EKG Phantom 320, Müller and Sebastiani Elektronik GmbH, Munich, Germany) was used to generate different heart rhythms and arrhythmias: sinus rhythm (SR) at 45, 60, 75, 90 and 120/min, supraventricular arrhythmias (e.g. sinus arrhythmia, atrial fibrillation) and ventricular arrhythmias (e.g. ventricular extrasystoles), pacemaker-ECGs, ST-changes and technical artifacts. The analysis of the image acquisition process was performed on a 64-row multidetector CT (Brilliance, Philips Medical Systems, Cleveland, USA). A prospectively triggered scan protocol as used for routine was applied (120 kV; 150 mA s; 0.4 s rotation and exposure time per scan; image acquisition predominantly in end-diastole at 75% R-R-interval, in arrythmias with a mean heart rate above 80/min in systole at 45% of the R-R-interval; FOV 25 cm). The mean dose length product (DLP) and its percentage increase from baseline (SR at 60/min) were determined. Result: Radiation exposure can increase significantly when the heart rhythm deviates from sinus rhythm. ECG-changes leading to a significant DLP increase (p 8 s) could be observed in bifocal pacemaker (12.8 s), pacemaker dysfunction (10.7 s), atrial fibrillation (10.3 s) and sinus arrhythmia (9.3 s). Conclusion: In prospectively ECG triggered CT, heart rate and rhythm can provoke different types of scanner performance, which can significantly alter radiation exposure and scan time. These results might have an important implication for indication, informed consent and contrast agent injection protocols

  2. Impact of heart rate and rhythm on radiation exposure in prospectively ECG triggered computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Luecke, Christian, E-mail: neep@gmx.de [University of Leipzig – Heart Center, Department of Diagnostic and Interventional Radiology, Strümpellstrasse 39, D-04289, Leipzig (Germany); Andres, Claudia; Foldyna, Borek [University of Leipzig – Heart Center, Department of Diagnostic and Interventional Radiology, Strümpellstrasse 39, D-04289, Leipzig (Germany); Nagel, Hans Dieter [Wissenschaft and Technik für die Radiologie, Buchhholz i.d.N (Germany); Hoffmann, Janine; Grothoff, Matthias; Nitzsche, Stefan; Gutberlet, Matthias; Lehmkuhl, Lukas [University of Leipzig – Heart Center, Department of Diagnostic and Interventional Radiology, Strümpellstrasse 39, D-04289, Leipzig (Germany)

    2012-09-15

    Purpose: To evaluate the influence of different heart rates and arrhythmias on scanner performance, image acquisition and applied radiation exposure in prospectively ECG triggered computed tomography (pCT). Materials and methods: An ECG simulator (EKG Phantom 320, Müller and Sebastiani Elektronik GmbH, Munich, Germany) was used to generate different heart rhythms and arrhythmias: sinus rhythm (SR) at 45, 60, 75, 90 and 120/min, supraventricular arrhythmias (e.g. sinus arrhythmia, atrial fibrillation) and ventricular arrhythmias (e.g. ventricular extrasystoles), pacemaker-ECGs, ST-changes and technical artifacts. The analysis of the image acquisition process was performed on a 64-row multidetector CT (Brilliance, Philips Medical Systems, Cleveland, USA). A prospectively triggered scan protocol as used for routine was applied (120 kV; 150 mA s; 0.4 s rotation and exposure time per scan; image acquisition predominantly in end-diastole at 75% R-R-interval, in arrythmias with a mean heart rate above 80/min in systole at 45% of the R-R-interval; FOV 25 cm). The mean dose length product (DLP) and its percentage increase from baseline (SR at 60/min) were determined. Result: Radiation exposure can increase significantly when the heart rhythm deviates from sinus rhythm. ECG-changes leading to a significant DLP increase (p < 0.05) were bifocal pacemaker (61%), pacemaker dysfunction (22%), SVES (20%), ventricular salvo (20%), and atrial fibrillation (14%). Significantly (p < 0.05) prolonged scan time (>8 s) could be observed in bifocal pacemaker (12.8 s), pacemaker dysfunction (10.7 s), atrial fibrillation (10.3 s) and sinus arrhythmia (9.3 s). Conclusion: In prospectively ECG triggered CT, heart rate and rhythm can provoke different types of scanner performance, which can significantly alter radiation exposure and scan time. These results might have an important implication for indication, informed consent and contrast agent injection protocols.

  3. HEART RATE AND MOTION ANALYSIS BY GPS IN BEACH SOCCER

    Directory of Open Access Journals (Sweden)

    Julen Castellano

    2010-03-01

    Full Text Available Although beach soccer has become increasingly popular in recent years very little scientific research has been conducted into the sport. A pilot study was carried out with the aim of examining the physiological (heart rate and physical (motion analysis responses of beach soccer players during competitive matches. Ten players (age 25.5 ± 0.5 years; height 1.80 ± 0.08 m; weight 78.2 ± 5.6 kg. were studied over five beach soccer matches. The physiological demands were analysed by measuring heart rate (HR using telemetric devices, while the physical profile was evaluated by recording motion and speed by means of GPS devices. During competitive matches, players obtained a HRmean of 165.2 bpm (86.5% HRmax, with 59.3% of the time participating (TP corresponding to values above 90% of the HRmax. The distance covered per minute of participation was 97.7 m, with 9.5% of this distance corresponding to high-intensity running and 2.5% to sprint; the work:rest ratio was 1.4:1 and the maximum speed 21.7 km·h-1. These results showed that beach soccer is an intermittent physical activity of greater intensity than other team games. It requires a major contribution from the anaerobic system as emphasis is placed on players making quick bursts of high-intensity activity separated by brief rest periods

  4. Tone Entropy Analysis of Foetal Heart Rate Variability

    Directory of Open Access Journals (Sweden)

    Ahsan Khandoker

    2015-03-01

    Full Text Available Development of the foetal autonomic nervous system can be indirectly understood by looking at the changes in beat to beat variability in foetal heart rates. This study presents Tone-Entropy (T-E analysis of foetal heart rate variability (HRV at multiple lags (1–8 to understand the influence of gestational ages (early and late on the development of the foetal autonomic nervous system (ANS. The analysis was based on foetal electrocardiograms (FECGs of 46 healthy foetuses of 20–32 weeks (early group and 22 foetuses of 35–41 weeks (late group. Tone represents sympatho-vagal balance and entropy the total autonomic activities. Results show that tone increases and entropy decreases at all lags for the late foetus group. On the other hand, tone decreases and entropy increases at lags 1–4 in the early foetus group. Increasing tone in late foetuses might represent significant maturation of sympathetic nervous systems because foetuses approaching to delivery period need increased sympathetic activity. T-E could be quantitative clinical index to determine the early foetuses from late ones on the basis of maturation of autonomic nervous system.

  5. Effects of Vibration and G-Loading on Heart Rate, Breathing Rate, and Response Time

    Science.gov (United States)

    Godinez, Angelica; Ayzenberg, Ruthie; Liston, Dorian B.; Stone, Leland S.

    2013-01-01

    Aerospace and applied environments commonly expose pilots and astronauts to G-loading and vibration, alone and in combination, with well-known sensorimotor (Cohen, 1970) and performance consequences (Adelstein et al., 2008). Physiological variables such as heart rate (HR) and breathing rate (BR) have been shown to increase with G-loading (Yajima et al., 1994) and vibration (e.g. Guignard, 1965, 1985) alone. To examine the effects of G-loading and vibration, alone and in combination, we measured heart rate and breathing rate under aerospace-relevant conditions (G-loads of 1 Gx and 3.8 Gx; vibration of 0.5 gx at 8, 12, and 16 Hz).

  6. Home telemonitoring of respiratory activity and heart rate variability in chronic heart failure patients: The challenge of the home or hospital in heart failure project

    OpenAIRE

    Pinna, Gd; Maestri, R.; Gobbi, E.; La Rovere, Mt; Scanferlato, Jl; Witkowski, T.; Kus-klinowska, A.; Andrews, D.; Johnson, P.; Capomolla, S.; Mortara, A.

    2003-01-01

    Nocturnal respiratory disorders and depressed heart rate variability are known predictors of poor prognosis in chronic heart failure (CHF) patients. Intermittent monitoring of cardiorespiratory signals while the patient is at home might thus allow early identification of clinical deterioration and prompt optimization of treatment, leading to reduced hospitalizations and mortality and improved quality of life. Within the European Community multicenter trial HHH (Home or Hospital in Heart Failu...

  7. Confronting a cardiovascular system model with heart rate and blood pressure data

    OpenAIRE

    Mcsharry, Pe; Mcguinness, Mj; Fowler, Ac

    2005-01-01

    The cardiovascular system may be investigated by observing fluctuations in the heart rate, blood pressure and rate of respiration. Its time evolution is governed by the baroreflex control mechanism, where the sympathetic and vagal nerves compete to increase and decrease the heart rate respectively. A nonlinear delay-differential equation model is constructed to describe this control mechanism and to explore the interactions between the heart rate and blood pressure. In this model, a time dela...

  8. HEART RATE AND BLOOD LACTATE RESPONSES TO CHANGQUAN AND DAOSHU FORMS OF MODERN WUSHU

    Directory of Open Access Journals (Sweden)

    Jerri Luiz Ribeiro

    2006-07-01

    Full Text Available The development of specific training designed to enhance physiological aspects of performance relies heavily on the availability of accurate and validity physiological data. In the combat sport of Wushu, katas are used to develop aerobic fitness. It is arguably important to assess and monitor heart rate (HR and lactate (La responses when designing effective training programs. The aim of this pilot study was to investigate heart rate and lactate responses to forms execution among Wushu combatants. Male elite modern Wushu athletes (n = 4 from a South Brazilian regional team participated in the study. Athletes were aged 22.5 ± 2.08 years old and had at least eight years of Wushu experience. Athletes carried out the Changquan and Daoshu forms in random order, HR and La were measured pre- and post-exercise. Results indicate that HR was 176 ± 3 and 176 ± 2 bpm and La was 4.38 ± 1.3 and 5.15 ± 1.07 mmol·l-1 for Changquan and Daoshu forms, respectively. There were no significantly differences in HR and La between the two forms. HR values represent 89.2 ± 1.1 and 89.1 ± 1.8% of age-predicted maximal heart rate and lactate was near of 4 mmol·l-1 point. In conclusion, training programs to Wushu combatants could target the range of physiological values cited above with no differences between two forms

  9. Mild mental stress in diabetes : changes in heart rate and subcutaneous blood-flow

    DEFF Research Database (Denmark)

    Hildebrandt, P; Mehlsen, J

    1985-01-01

    A TV-game of tennis of 20 min duration was used to study the influence of mild mental stress on subcutaneous blood-flow (SBF), blood-pressure and heart rate in nine insulin-dependent diabetics and nine healthy subjects. SBF was measured on the thigh by local clearance of xenon-133. Measurements were made before, during and after the period of stress. During stress, SBF increased significantly by 26% in the healthy subjects, while SBF remained unchanged in the diabetics. The difference between the two groups was significant (P less than 0.05). Following stress, SBF returned to pre-stress level in the healthy subjects, while a significant decrease of 33% was observed in the diabetics. The pre-stress heart rate level was higher and the stress-induced increase in heart rate was less in the diabetics compared with the healthy subjects (P less than 0.05). During the stress a slight--but insignificant--increase in blood-pressure was observed in both groups. In conclusion, we found that even mild mental strain influences SBF in both normal subjects and in diabetics. The induced alterations in the two groups are different, probably because of a slight parasympathetic dysfunction in the diabetics.

  10. Changes in heart-rate variability of survivors of nasopharyngeal cancer during Tai Chi Qigong practice.

    Science.gov (United States)

    Fong, Shirley S M; Wong, Janet Y H; Chung, Louisa M Y; Yam, Timothy T T; Chung, Joanne W Y; Lee, Y M; Chow, Lina P Y; Luk, W S; Ng, Shamay S M

    2015-05-01

    [Purpose] To explore the changes in heart-rate variability (HRV) of survivors of nasopharyngeal cancer (NPC) before, during, and after a Tai Chi (TC) Qigong exercise. [Subjects and Methods] Eleven survivors of NPC participated voluntarily in the study. The heart rate of each participant was measured continuously for 1 minute before the TC Qigong intervention, during the 5-minute TC Qigong intervention, and for 1 minute after the intervention, using a Polar heart-rate monitor. Spectral HRV was expressed in terms of normalised low frequency (LF) power, normalised high frequency (HF) power, and the low frequency/high frequency (LF/HF) power ratio. [Results] Both the LF-power and the HF-power components had significant time effects. However, the time effect of the LF/HF power ratio was not significant. Post hoc contrast analysis revealed a significant decrease in LF power and a concomitant increase in HF power during the 4th minute and 5th minute of the TC Qigong exercise. [Conclusion] Five minutes of TC Qigong exercise was found to improve HRV by increasing HF power and decreasing LF power, but these effects were transient. TC Qigong might be an appropriate exercise for improving the ANS function and psychological and cardiac health of survivors of NPC. PMID:26157266

  11. Vagally mediated heart rate variability and heart rate entropy as predictors of treatment outcome in flight phobia.

    Science.gov (United States)

    Bornas, Xavier; Llabrés, Jordi; Tortella-Feliu, Miquel; Fullana, Miquel A; Montoya, Pedro; López, Ana; Noguera, Miquel; Gelabert, Joan M

    2007-10-01

    In the present study a computer-assisted exposure-based treatment was applied to 54 flight phobics and the predictive role of vagally mediated heart rate (HR) variability (high frequency, 0.15-0.4 Hz band power) and heart rate entropy (HR time series sample entropy) on treatment outcome was investigated. Both physiological measures were taken under controlled breathing at 0.2 Hz and during exposure to a fearful sequence of audiovisual stimuli. Hierarchical regression analyses were conducted to assess the predictive power of these variables in these conditions on treatment self-report measures at the end of treatment and at 6 months follow-up, as well as on the behavioral treatment outcome (i.e. flying at the end of treatment). Regression models predicting significant amounts of outcome variance could be built only when HR entropy was added to the HR variability measure in a second step of the regression analyses. HR variability alone was not found to be a good predictor of neither self-reported nor behavioral treatment outcomes. PMID:17765387

  12. 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.

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

    Scientific Electronic Library Online (English)

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

    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 1 [...] 5 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.

  14. Noninvasive coronary angiography using 64-slice spiral computed tomography in an unselected patient collective: Effect of heart rate, heart rate variability and coronary calcifications on image quality and diagnostic accuracy

    International Nuclear Information System (INIS)

    Objective: The aim of this study was to assess the impact of heart rate, heart rate variability and calcification on image quality and diagnostic accuracy in an unselected patient collective. Subjects and methods: One hundred and two consecutive patients with known or suspected coronary artery disease underwent both 64-MSCT and invasive coronary angiography. Image quality (IQ) was assessed by independent observers using a 4-point scale from excellent (1) to non-diagnostic (4). Accuracy of MSCT regarding detection or exclusion of significant stenosis (>50%) was evaluated on a per segment basis in a modified AHA 13-segment model. Effects of heart rate, heart rate variability, calcification and body mass index (BMI) on IQ and accuracy were evaluated by multivariate regression. IQ and accuracy were further analysed in subgroups of significant predictor variables and simple regression performed to calculate thresholds for adequate IQ. Results: Mean heart rate was 68.2 ± 13.3 bpm, mean heart rate variability 11.5 ± 16.0 beats per CT-examination (bpct) and median Agatston score 226.5. Average IQ score was 2 ± 0.6 whilst diagnostic quality was obtained in 89% of segments. Overall sensitivity, specificity, PPV or NPV was 91.2%, 99.2%, 95.3% or 98.3%. According to multivariate regression, overall IQ was significantly related to heart rate and calcification (P = 0.0038; P < 0.0001). The effect of heart rate variability was limited to IQ of RCA segments (P = 0.018); BMI was noof RCA segments (P = 0.018); BMI was not related to IQ (P = 0.52). Calcification was the only predictor variable with significant effect on the number of non-diagnostic segments (P < 0.0001). In a multivariate regression, calcification was also the single factor with impact on diagnostic accuracy (P = 0.0049). Conclusion: Whilst heart rate, heart rate variability and calcification all show an inverse correlation to IQ, severe calcium burden remains the single factor with translation of such effect into decrease of diagnostic accuracy

  15. Dynamics of the heart rate variability in patients with atrial fibrillation during atorvastatin therapy

    Directory of Open Access Journals (Sweden)

    E.S. Kozlova

    2008-01-01

    Full Text Available Aim. To evaluate the heart rate variability (HRV in patients with ischemic heart disease (IHD and paroxysmal atrial fibrillation (AF during atorvastatin therapy.Material and methods. 60 patients with IHD and paroxysmal AF were included in the study. Patients were divided into two groups – control group (basic antiarrhythmic therapy and second group (basic antiarrhythmic therapy and atorvastatin (Liptonorm, Pharmstandart, Russia 10mg/day. HRV was compared before and after 3 months of therapy in both groups.Results. Liptonorm significantly improved HRV indices in comparison with basic therapy alone: RMSSD increased on 33% (?<0,02, total power (TP of spectrum on 28% (?<0,03 and high frequency (HF component on 53 % (?<0,01.Conclusion. Liptonorm therapy improves autonomic balance in patients with IHD and paroxysmal AF.

  16. Heart rate and blood lactate responses to changquan and daoshu forms of modern wushu.

    Science.gov (United States)

    Ribeiro, Jerri Luiz; de Castro, Bruno Ogoday S D; Rosa, Caio S; Baptista, Rafael R; Oliveira, Alvaro R

    2006-01-01

    The development of specific training designed to enhance physiological aspects of performance relies heavily on the availability of accurate and validity physiological data. In the combat sport of Wushu, katas are used to develop aerobic fitness. It is arguably important to assess and monitor heart rate (HR) and lactate (La) responses when designing effective training programs. The aim of this pilot study was to investigate heart rate and lactate responses to forms execution among Wushu combatants. Male elite modern Wushu athletes (n = 4) from a South Brazilian regional team participated in the study. Athletes were aged 22.5 ± 2.08 years old and had at least eight years of Wushu experience. Athletes carried out the Changquan and Daoshu forms in random order, HR and La were measured pre- and post-exercise. Results indicate that HR was 176 ± 3 and 176 ± 2 bpm and La was 4.38 ± 1.3 and 5.15 ± 1.07 mmol·l(-1) for Changquan and Daoshu forms, respectively. There were no significantly differences in HR and La between the two forms. HR values represent 89.2 ± 1.1 and 89.1 ± 1.8% of age-predicted maximal heart rate and lactate was near of 4 mmol·l(-1) point. In conclusion, training programs to Wushu combatants could target the range of physiological values cited above with no differences between two forms. Key PointsHeart rate and lactate responses are not significantly different between Changquan and Daoshu forms for Wushu combatants.The Wushu katas could be used to develop aerobic fitness. PMID:24357970

  17. Heart rate variability in risk stratification of cardiac patients.

    Science.gov (United States)

    Huikuri, Heikki V; Stein, Phyllis K

    2013-01-01

    Heart rate (HR) variability has been extensively studied in cardiac patients, especially in patients surviving an acute myocardial infarction (AMI) and also in patients with congestive heart failure (CHF) or left ventricular (LV) dysfunction. The majority of studies have shown that patients with reduced or abnormal HR variability have an increased risk of mortality within a few years after an AMI or after a diagnosis of CHF/LV dysfunction. Various measures of HR dynamics, such as time-domain, spectral, and non-linear measures of HR variability have been used in risk stratification. The prognostic power of various measures, except of those reflecting rapid R-R interval oscillations, has been almost identical, albeit some non-linear HR variability measures, such as short-term fractal scaling exponent have provided somewhat better prognostic information than the others. Abnormal HR variability predicts both sudden and non-sudden cardiac death. Because of remodeling of the arrhythmia substrate after AMI, early measurement of HR variability to identify those at high risk should likely be repeated later in order to assess the risk of fatal arrhythmia events. Future randomized trials using HR variability/turbulence as one of the pre-defined inclusion criteria will show whether routine measurement of HR variability/turbulence will become a routine clinical tool for risk stratification of cardiac patients. PMID:24215747

  18. Freqüência cardíaca e risco cardiovascular / Heart rate and cardiovascular risk

    Scientific Electronic Library Online (English)

    Luiz Antonio Machado, César.

    2007-10-01

    Full Text Available A freqüência cardíaca (FC) também está no centro das determinantes do tempo de vida dos seres vivos animais. Há quase uma constante quando se multiplica a FC pelo número de anos que, em média, vive um animal. O ser humano também tem correlações interessantes de tempo de vida e FC, com estudos epidem [...] iológicos demonstrando maior sobrevivência naqueles com menor FC em repouso, hipertensos, com doença coronariana e na população geral. Neste artigo, revemos estes estudos epidemiológicos e a perspectiva de se, de fato reduzindo a FC, poderemos aumentar o tempo de vida, no caso dos pacientes com doença cardiovascular, de forma independente de outros fatores. Abstract in english Heart rate (HR) is known to be one of the factors that in the animal world are related to mortality. When one multiplies resting HR by the average life time, for each animal species, the result is almost the same number, similar to a constant. Apparently, each class of living beings has its "maximal [...] number of heart beats for a life". Herein considerations are made about the relationship between HR and survival in human beings. Some epidemiological studies are reviewed, especially those related to cardiovascular and coronary diseases correlated to deaths and discussions are directed towards the perspective of living longer by lowering the HR.

  19. Freqüência cardíaca e risco cardiovascular Heart rate and cardiovascular risk

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Machado César

    2007-10-01

    Full Text Available A freqüência cardíaca (FC também está no centro das determinantes do tempo de vida dos seres vivos animais. Há quase uma constante quando se multiplica a FC pelo número de anos que, em média, vive um animal. O ser humano também tem correlações interessantes de tempo de vida e FC, com estudos epidemiológicos demonstrando maior sobrevivência naqueles com menor FC em repouso, hipertensos, com doença coronariana e na população geral. Neste artigo, revemos estes estudos epidemiológicos e a perspectiva de se, de fato reduzindo a FC, poderemos aumentar o tempo de vida, no caso dos pacientes com doença cardiovascular, de forma independente de outros fatores.Heart rate (HR is known to be one of the factors that in the animal world are related to mortality. When one multiplies resting HR by the average life time, for each animal species, the result is almost the same number, similar to a constant. Apparently, each class of living beings has its "maximal number of heart beats for a life". Herein considerations are made about the relationship between HR and survival in human beings. Some epidemiological studies are reviewed, especially those related to cardiovascular and coronary diseases correlated to deaths and discussions are directed towards the perspective of living longer by lowering the HR.

  20. Heart Rate Variability in Cavalier King Charles Spaniels with Different Degree of Myxomatous Mitral Valve Disease

    DEFF Research Database (Denmark)

    Rasmussen, Caroline Elisabeth; Falk, Bo Torkel

    Heart Rate Variability in Cavalier King Charles Spaniels with Different Degree of Myxomatous Mitral Valve Disease Rasmussen, C.E. 1, Falk, T. 1, Zois, N.E. 1, Moesgaard, S.G. 1, Häggström, J. 2, Pedersen, H.D. 3 and Olsen, L.H1. 1Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark, 2Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden; and 3Novo Nordic A/S, Maaloev, Denmark. Introduction: Modulation of heart rate by the autonomic nervous system can indirectly be measured by heart rate variability (HRV). Reduced HRV is seen in dogs with heart failure secondary to myxomatous mitral valve disease (MMVD). However, HRV is suggested to increase with disease progression in dogs with early stages of MMVD. Comparable results are found in people with primary mitral valve prolapse, a disease resembling canine MMVD. Aim: To associate progression of MMVD in dogs with time and frequency domain HRV, analysed from 24-hour electrocardiography. Materials and Methods: Eighty-one Cavalier King Charles Spaniels (CKCS) were examined by echocardiography and 24-hour electrocardiography. CKCS were divided into 4 groups: 1) no or minimal mitral regurgitation (MR) (MR jet=15% of the left atrial area) and no murmur, 2) mild MR (20%50%) and no clinical signs of heart failure, 4) left atrium to aortic root ratio >1.5, clinical signs of heart failure and furosemide responsiveness. Results: Ten out of 13 HRV variables decreased with increasing MMVD severity. In group 1, 10 HRV variables were increased compared to group 3 and 4 (P<0.05) and 2 HRV variables were increased compared to group 2 (P<0.04). Eight and 10 HRV variables were increased in group 2 compared to group 3 (P<0.01) and group 4 (P<0.001), respectively. Group 1 and 2 were younger than group 3 and 4 (P<0.0001). Only 2 HRV variables were influenced by age. Discussion and conclusion: Most HRV variables decreased with progression of MMVD in dogs; even prior to the development of overt congestive heart failure.

  1. DIFFERENT TIMES OF THE DAY AND RECOVERY OF HEART RATE AND RESPIRATORY RATE AFTER WORKOUT – A COMPARISON

    Directory of Open Access Journals (Sweden)

    James Minj

    2015-04-01

    Full Text Available This study was done to compare the amount of recovery at different times of the day i.e. Morning, Afternoon and Evening. The researcher has selected a total of five subjects purposively with the age 19±2 years from Jiwaji University, Gwalior. The heart rate and respiratory rate were recorded just after the finish of the specific anaerobic workout and after fixed regular subsequent intervals. The recovered heart rate and respiratory rate (from the reserved were compared with the help of one way analysis of variance. No significant differences were found in the amount of recovery at different times of the day in heart rate and respiratory rate.

  2. Atrial and Ventricular Rate Response and Patterns of Heart Rate Acceleration during Maternal–Fetal Terbutaline Treatment of Fetal Complete Heart Block

    OpenAIRE

    Cuneo, Bettina F.; Zhao, Hui; Strasburger, Janette F.; Ovadia, Marc; Huhta, James C.; Wakai, Ronald T.

    2007-01-01

    Terbutaline is used to treat fetal bradycardia in the setting of complete heart block (CHB); however, little is known of its effects on atrial and ventricular beat rates or patterns of heart rate (HR) acceleration. Fetal atrial and ventricular beat rates were compared before and after transplacental terbutaline treatment (10 to 30 mg/day) by fetal echocardiography in 17 fetuses with CHB caused by immune-mediated damage to a normal conduction system (isoimmune, n = 8) or a congenitally malform...

  3. State level correlations between high heart attack and stroke symptomology knowledge scores and CVD risk factors and mortality rates

    Directory of Open Access Journals (Sweden)

    Mary Nawal Lutfiyya

    2013-09-01

    Full Text Available Introduction: In 2008, cardiovascular disease (CVD accounted for one in three deaths in the United States. Epidemiological analyses suggest that two or more risk factors are the indicator of high risk and/or poor CVD outcomes. Knowledge of heart attack and stroke symptomology has been the focus of much research based on the assumption that accurate identification of an event is critical to reducing time to treatment. There is a paucity of research showing a clear association between knowledge of heart attack and stroke symptomology, risk factors, and mortality rates. In this study, we hypothesized that high stroke and heart attack symptomology knowledge scores would correspond to lower stroke or CVD mortality rankings as well as to a lower prevalence of two or more CVD risk factors. Methods: State was the unit of analysis used to examine data from two different sources and combined into a customized database. The first source was a multiyear Behavioral Risk Factor Surveillance Survey (BRFSS heart attack and stroke symptom knowledge module database. CVD and stroke mortality data used came from the American Heart Association’s (AHA 2012 Heart Disease and Stroke Statistics Update. Spearman’s Rho was the test statistic. Results: A moderate negative correlation was found between high heart attack and stroke symptom knowledge scores and the percentage of adults with two or more CVD or stroke risk factors. Likewise, a similar correlation resulted from the two variables, high heart attack and stroke symptoms knowledge score and CVD mortality rank. Conclusions: This study demonstrated a significant relationship between high heart attack and stroke symptom knowledge and lower CVD mortality rates and lower prevalence of two or more CVD risk factors at the state level. Our findings suggest that it is important to continue education efforts regarding heart attack and stroke symptom knowledge. Pharmacists are one group of health care providers who could enhance the needed public health education efforts.

  4. Automated Fetal Heart Rate Analysis in Labor: Decelerations and Overshoots

    International Nuclear Information System (INIS)

    Electronic fetal heart rate (FHR) recording is a standard way of monitoring fetal health in labor. Decelerations and accelerations usually indicate fetal distress and normality respectively. But one type of acceleration may differ, namely an overshoot that may atypically reflect fetal stress. Here we describe a new method for detecting decelerations, accelerations and overshoots as part of a novel system for computerized FHR analysis (OxSyS). There was poor agreement between clinicians when identifying these FHR features visually, which precluded setting a gold standard of interpretation. We therefore introduced 'modified' Sensitivity (SE deg.) and 'modified' Positive Predictive Value (PPV deg.) as appropriate performance measures with which the algorithm was optimized. The relation between overshoots and fetal compromise in labor was studied in 15 cases and 15 controls. Overshoots showed promise as an indicator of fetal compromise. Unlike ordinary accelerations, overshoots cannot be considered to be reassuring features of fetal health.

  5. Breathing frequency bias in fractal analysis of heart rate variability.

    Science.gov (United States)

    Perakakis, Pandelis; Taylor, Michael; Martinez-Nieto, Eduardo; Revithi, Ioanna; Vila, Jaime

    2009-09-01

    Detrended Fluctuation Analysis (DFA) is an algorithm widely used to determine fractal long-range correlations in physiological signals. Its application to heart rate variability (HRV) has proven useful in distinguishing healthy subjects from patients with cardiovascular disease. In this study we examined the effect of respiratory sinus arrhythmia (RSA) on the performance of DFA applied to HRV. Predictions based on a mathematical model were compared with those obtained from a sample of 14 normal subjects at three breathing frequencies: 0.1Hz, 0.2Hz and 0.25Hz. Results revealed that: (1) the periodical properties of RSA produce a change of the correlation exponent in HRV at a scale corresponding to the respiratory period, (2) the short-term DFA exponent is significantly reduced when breathing frequency rises from 0.1Hz to 0.2Hz. These findings raise important methodological questions regarding the application of fractal measures to short-term HRV. PMID:19559748

  6. Wearable depression monitoring system with heart-rate variability.

    Science.gov (United States)

    Roh, Taehwan; Sunjoo Hong; Hoi-Jun Yoo

    2014-08-01

    A wearable depression monitoring system is proposed with an application-specific system-on-chip (SoC) solution. The SoC is designed to accelerate the filtering and feature extraction of heart-rate variability (HRV) from the electrocardiogram (ECG). Thanks to the SoC solution and planar-fashionable circuit board (P-FCB), the monitoring system becomes a low-power wearable system. Its dimension is 14cm × 7cm with 5mm thickness covering the chest band for convenient usage. In addition, with 3.7V 500mAh battery, its lifetime is at least 10 hours. For user's convenience, the system is interfacing to smart phones through Bluetooth communication. With the features of the HRV and Beck depression inventory (BDI), the smart phone application trains and classifies the user's depression scale with 71% of accuracy. PMID:25570021

  7. Heart Rate Variability Analysis Using Threshold of Wavelet Package Coefficients

    CERN Document Server

    Kheder, G; Massoued, M Ben; Samet, M

    2009-01-01

    In this paper, a new efficient feature extraction method based on the adaptive threshold of wavelet package coefficients is presented. This paper especially deals with the assessment of autonomic nervous system using the background variation of the signal Heart Rate Variability HRV extracted from the wavelet package coefficients. The application of a wavelet package transform allows us to obtain a time-frequency representation of the signal, which provides better insight in the frequency distribution of the signal with time. A 6 level decomposition of HRV was achieved with db4 as mother wavelet, and the above two bands LF and HF were combined in 12 specialized frequencies sub-bands obtained in wavelet package transform. Features extracted from these coefficients can efficiently represent the characteristics of the original signal. ANOVA statistical test is used for the evaluation of proposed algorithm.

  8. [Analysis of heart rate variability. Mathematical description and practical application].

    Science.gov (United States)

    Sammito, S; Böckelmann, I

    2015-03-01

    The analysis of heart rate variability (HRV) has recently become established as a non-invasive measurement for estimation of demands on the cardiovascular system. The HRV reflects the interaction of the sympathetic and parasympathetic nervous systems and allows the influence of the autonomic nervous system on the regulation of the cardiovascular system to be mathematically described. This review explicates the analysis method of HRV for time, frequency and non-linear methods as well as the range of parameters and the demand on acquisition time. The necessity and possibilities of artefact correction and advice for the selection of a reasonable acquisition period are discussed and standard values for selected HRV parameters are presented. PMID:25298003

  9. Heart Rate Variability in Patients With Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Fevzi BEKTA?LI

    2009-09-01

    Full Text Available Objective: The aims of the present study were to compare heart rate variability (HRV parameters of patients with multiple sclerosis (MS and healthy controls and to investigate the correlations between HRV parameters and disease duration, subtype and severity.Methods: Thirty-two patients with MS [18 with relapsing-remitting MS (RRMS, 4 with primary progressive MS (PPMS and 10 with secondary progressive MS (SPMS] and 32 healthy, age-and sex-matched volunteers were included. HRV was evaluated by frequency-domain spectral analysis method; total power (TP, low frequency (LF power, high frequency (HF power, very low frequency (VLF power in absolute values and in normalized units (n.u. and the ratio of LF to HF was used.Results: The patients had lower TP, VLF, LF, HF and HF n.u. and higher LF n.u. and the ratio of LF to HF reflecting overall decreased HRV accompanied by sympathetic overactivity and parasympathetic hypoactivity. There was no association between EDSS score and HRV parameters; however, we found a positive correlation between disease duration and LF n.u. We did not find significant differences between the patients with RRMS and the patients with SPMS regarding cardiac autonomic activity. Although TP, LF power, HF power and VLF power of the patients with PPMS were lower than of the patients with RRMS and the patients with SPMS, no statistical analysis could be made for this group due to inadequate number of the patients in this group.Interpretation: Patients with MS have higher sympathetic and lower parasympathetic regulation activity of heart rate. Disease duration, rather than severity seems to be associated with increased sympathetic activity.

  10. Simple and Cost-effective Heart Rate Meter Using PIC Microcontroller

    Directory of Open Access Journals (Sweden)

    Souvik Das

    2014-04-01

    Full Text Available One of the major and significant physiological parameters of human cardiovascular system is the heart rate. Heart rate is represented by the number of times the heart beats per minute. The heart rate data can reflect various physiological states such as stress at work, concentration on tasks, drowsiness, biological workload, and the active state of the autonomic nervous system. Human cardiac dynamics are driven by the complex nonlinear interactions of two competing forces: sympathetic regulation increases and parasympathetic regulation decreases the heart rate. Monitoring of heart rate plays an important role in conveying the status of cardiovascular system and clinically correlated information to medical professionals. Therefore, heart rate measurement is regarded as an essential parameter in patient care monitoring system. Human heart rate can be measured either by the ECG waveform or by sensing the pulse, the rhythmic expansion and contraction of an artery as blood is forced through it by the regular contractions of the heart. The pulse can be sensed from those areas where the artery is close to the skin. This research paper highlights on the design of a microcontroller (PIC series based simple and cost-effective heart rate meter that is able to capture the pulse from human finger tip by sensing the change in blood volume. The heart rates of fifteen healthy normal subjects (students of age 21-22 yrs. both in relaxed and exercised (stressed states were measured using the designed system. The heart data, measured from the designed system showed satisfactory result while compared to a standard heart rate meter. The Also, the designed meter, being non-invasive one, can easily find its place in health care monitoring system.

  11. Skeletal muscle signaling and the heart rate and blood pressure response to exercise : insight from heart rate pacing during exercise with a trained and a deconditioned muscle group

    DEFF Research Database (Denmark)

    Mortensen, Stefan P; Svendsen, Jesper H

    2013-01-01

    Endurance training lowers heart rate and blood pressure responses to exercise, but the mechanisms and consequences remain unclear. To determine the role of skeletal muscle for the cardioventilatory response to exercise, 8 healthy young men were studied before and after 5 weeks of 1-legged knee-extensor training and 2 weeks of deconditioning of the other leg (leg cast). Hemodynamics and muscle interstitial nucleotides were determined during exercise with the (1) deconditioned leg, (2) trained leg, and (3) trained leg with atrial pacing to the heart rate obtained with the deconditioned leg. Heart rate was ? 15 bpm lower during exercise with the trained leg (P

  12. Deficient maternal zinc intake—but not folate—is associated with lower fetal heart rate variability

    Science.gov (United States)

    Spann, Marisa N.; Smerling, Jennifer; Gustafsson, Hanna; Foss, Sophie; Altemus, Margaret; Monk, Catherine

    2015-01-01

    Objective Few studies of maternal prenatal diet and child development examine micronutrient status in relation to fetal assessment. Methods Twenty-four-hour dietary recall of zinc and folate and 20min of fetal heart rate were collected from 3rd trimester pregnant adolescents. Results Deficient zinc was associated with less fetal heart rate variability. Deficient folate had no associations with HRV. Neither deficient zinc nor deficient folate was related to fetal heart rate. Conclusions These findings, from naturalistic observation, are consistent with emerging data on prenatal zinc supplementation using a randomized control design. Practical Implication Taken together, the findings suggest that maternal prenatal zinc intake is an important and novel factor for understanding child ANS development. PMID:25658874

  13. The effect of competition on heart rate during kart driving: A field study

    OpenAIRE

    Yamakoshi Takehiro; Matsumura Kenta; Yamakoshi Yasuhiro; Rolfe Peter

    2011-01-01

    Abstract Background Both the act of competing, which can create a kind of mental stress, and participation in motor sports, which induces physical stress from intense g-forces, are known to increase heart rate dramatically. However, little is known about the specific effect of competition on heart rate during motor sports, particularly during four-wheel car driving. The goal of this preliminary study, therefore, was to investigate whether competition increases heart rate under such situations...

  14. Identification of heart rate–associated loci and their effects on cardiac conduction and rhythm disorders

    OpenAIRE

    Den Hoed, Marcel; Eijgelsheim, Mark; Esko, To?nu; Brundel, Bianca J. J. M.; Peal, David S.; Evans, David M.; Nolte, Ilja M.; Segre?, Ayellet V.; Holm, Hilma; Handsaker, Robert E.; Westra, Harm-jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a rol...

  15. High-Frequency Heart Rate Variability Linked to Affiliation with a New Group

    OpenAIRE

    Sahdra, Baljinder K.; Ciarrochi, Joseph; Parker, Philip D.

    2015-01-01

    This study tests the hypothesis that high levels of high-frequency heart rate variability (HF-HRV) predisposes individuals to affiliate with new groups. Resting cardiac physiological recordings were taken before and after experimental sessions to measure trait high-frequency heart rate variability as an index of dispositional autonomic influence on heart rate. Following an experimental manipulation of priming of caring-related words, participants engaged in a minimal group paradigm, in which ...

  16. Exercise heart rates at different serum digoxin concentrations in patients with atrial fibrillation.

    OpenAIRE

    Beasley, R.; Smith, D. A.; Mchaffie, D. J.

    1985-01-01

    Heart rate at rest and during increasing workloads was measured in a double blind study of 12 patients with chronic atrial fibrillation when serum concentrations of digoxin were nil and at low and high therapeutic values. Twelve normal subjects were studied for comparison. The heart rate at all levels of exercise in most patients with atrial fibrillation was not adequately controlled by any serum digoxin concentration tested despite a reduction in heart rate with increasing serum digoxin conc...

  17. Influence of blood glucose on heart rate and cardiac autonomic function. The DESIR study.

    OpenAIRE

    Valensi, Paul; Extramiana, Fabrice; Lange, Ce?line; Cailleau, Martine; Haggui, Abdeddayem; Maison Blanche, Pierre; Tichet, Jean; Balkau, Beverley

    2011-01-01

    OBJECTIVES: ? To evaluate in a general population, the relationships between dysglycaemia, insulin resistance and metabolic variables, and heart rate, heart rate recovery and heart rate variability. METHODS: ? Four hundred and forty-seven participants in the Data from an Epidemiological Study on the Insulin Resistance syndrome (DESIR) study were classified according to glycaemic status over the preceding 9 years. All were free of self-reported cardiac antecedents and were not taking drugs...

  18. Reduction of heart rate by omega-3 fatty acids and the potential underlying mechanisms

    OpenAIRE

    JingXuanKang

    2012-01-01

    An elevated resting heart rate is one of the strongest predictors of cardiovascular mortality and is independently associated with sudden cardiac death (SCD). Agents capable of reducing heart rate without significant side effects are therefore of particular interest for the prevention of SCD. Recent human and animal studies have shown that omega-3 fatty acids can reduce heart rate. Our work has shown that omega-3 fatty acids significantly reduce membrane electrical excitability of the cardiac...

  19. A novel technique for fetal heart rate estimation from Doppler ultrasound signal

    Directory of Open Access Journals (Sweden)

    Jezewski Janusz

    2011-10-01

    Full Text Available Abstract Background The currently used fetal monitoring instrumentation that is based on Doppler ultrasound technique provides the fetal heart rate (FHR signal with limited accuracy. It is particularly noticeable as significant decrease of clinically important feature - the variability of FHR signal. The aim of our work was to develop a novel efficient technique for processing of the ultrasound signal, which could estimate the cardiac cycle duration with accuracy comparable to a direct electrocardiography. Methods We have proposed a new technique which provides the true beat-to-beat values of the FHR signal through multiple measurement of a given cardiac cycle in the ultrasound signal. The method consists in three steps: the dynamic adjustment of autocorrelation window, the adaptive autocorrelation peak detection and determination of beat-to-beat intervals. The estimated fetal heart rate values and calculated indices describing variability of FHR, were compared to the reference data obtained from the direct fetal electrocardiogram, as well as to another method for FHR estimation. Results The results revealed that our method increases the accuracy in comparison to currently used fetal monitoring instrumentation, and thus enables to calculate reliable parameters describing the variability of FHR. Relating these results to the other method for FHR estimation we showed that in our approach a much lower number of measured cardiac cycles was rejected as being invalid. Conclusions The proposed method for fetal heart rate determination on a beat-to-beat basis offers a high accuracy of the heart interval measurement enabling reliable quantitative assessment of the FHR variability, at the same time reducing the number of invalid cardiac cycle measurements.

  20. Decreased variability of the 6-minute walk test by heart rate correction in patients with neuromuscular disease

    DEFF Research Database (Denmark)

    Prahm, Kira P; Witting, Nanna

    2014-01-01

    OBJECTIVE: The 6-minute walk test is widely used to assess functional status in neurological disorders. However, the test is subject to great inter-test variability due to fluctuating motivation, fatigue and learning effects. We investigated whether inter-test variability of the 6MWT can be reduced by heart rate correction. METHODS: Sixteen patients with neuromuscular diseases, including Facioscapulohumeral muscular dystrophy, Limb-girdle muscular dystrophy, Charcot-Marie-Tooths, Dystrophia Myotonica and Congenital Myopathy and 12 healthy subjects were studied. Patients were excluded if they had cardiac arrhythmias, if they received drug treatment for hypertension or any other medical conditions that could interfere with the interpretation of the heart rate and walking capability. All completed three 6-minute walk tests on three different test-days. Heart rate was measured continuously. RESULTS: Successive standard 6-minute walk tests showed considerable learning effects between Tests 1 and 2 (4.9%; P = 0.026), and Tests 2 and 3 (4.5%; P = 0.020) in patients. The same was seen in controls between Tests 1 and 2 (8.1%; P = 0.039)). Heart rate correction abolished this learning effect. CONCLUSION: A modified 6-minute walk test, by correcting walking distance with average heart rate during walking, decreases the variability among repeated 6-minute walk tests, and should be considered as an alternative outcome measure to the standard 6-minute walk test in future clinical follow-up and treatment trials.

  1. Decreased Variability of the 6-Minute Walk Test by Heart Rate Correction in Patients with Neuromuscular Disease

    DEFF Research Database (Denmark)

    Prahm, Kira Philipsen; Witting, Nanna

    2014-01-01

    OBJECTIVE: The 6-minute walk test is widely used to assess functional status in neurological disorders. However, the test is subject to great inter-test variability due to fluctuating motivation, fatigue and learning effects. We investigated whether inter-test variability of the 6MWT can be reduced by heart rate correction. METHODS: Sixteen patients with neuromuscular diseases, including Facioscapulohumeral muscular dystrophy, Limb-girdle muscular dystrophy, Charcot-Marie-Tooths, Dystrophia Myotonica and Congenital Myopathy and 12 healthy subjects were studied. Patients were excluded if they had cardiac arrhythmias, if they received drug treatment for hypertension or any other medical conditions that could interfere with the interpretation of the heart rate and walking capability. All completed three 6-minute walk tests on three different test-days. Heart rate was measured continuously. RESULTS: Successive standard 6-minute walk tests showed considerable learning effects between Tests 1 and 2 (4.9%; P = 0.026), and Tests 2 and 3 (4.5%; P = 0.020) in patients. The same was seen in controls between Tests 1 and 2 (8.1%; P = 0.039)). Heart rate correction abolished this learning effect. CONCLUSION: A modified 6-minute walk test, by correcting walking distance with average heart rate during walking, decreases the variability among repeated 6-minute walk tests, and should be considered as an alternative outcome measure to the standard 6-minute walk test in future clinical follow-up and treatment trials.

  2. The correlation between psychological intervention and heart rate,systolic pressure in patients of cervical cancer treated with interventional chemoembolization

    International Nuclear Information System (INIS)

    Objective: To discuss the effect of psychological intervention on the heart rate, systolic pressure of the patients with cervical cancer who are treated with interventional chemoembolization. Methods: Eighty patients with cervical cancer were randomly and equally divided into two groups. Transcatheter arterial chemoembolization (TACE) was performed in all cases. Patients in study group (n=10) received systemic psychological intervention 30 minutes before TACE. The heart rate and systolic pressure of the patients were measured when TACE started. The results were compared with that obtained at the time of admission. Patients in control group (n=10) did not receive systemic psychological intervention before TACE and their heart rate and systolic pressure were measured in the same way as in study group. Results: At the time TACE started the heart rate and systolic pressure of the patients in study group were significantly lower than that in control group (P < 0.05). Conclusion: Preoperative psychological intervention is very helpful for reducing psychological stress and mental tension,in stabilizing heart rate and systolic pressure of the patients with cervical cancer who are treated with TACE. (authors)

  3. Changes in Heart Rate Variability after Coronary Artery Bypass Grafting and Clinical Importance of These Findings

    Science.gov (United States)

    Lakusic, Nenad; Mahovic, Darija; Cerkez Habek, Jasna; Novak, Miroslav; Cerovec, Dusko

    2015-01-01

    Heart rate variability is a physiological feature indicating the influence of the autonomic nervous system on the heart rate. Association of the reduced heart rate variability due to myocardial infarction and the increased postinfarction mortality was first described more than thirty years ago. Many studies have unequivocally demonstrated that coronary artery bypass grafting surgery generally leads to significant reduction in heart rate variability, which is even more pronounced than after myocardial infarction. Pathophysiologically, however, the mechanisms of heart rate variability reduction associated with acute myocardial infarction and coronary artery bypass grafting are different. Generally, heart rate variability gradually recovers to the preoperative values within six months of the procedure. Unlike the reduced heart rate variability in patients having sustained myocardial infarction, a finding of reduced heart rate variability after coronary artery bypass surgery is not considered relevant in predicting mortality. Current knowledge about changes in heart rate variability in coronary patients and clinical relevance of such a finding in patients undergoing coronary artery bypass grafting are presented. PMID:26078960

  4. Pharmacological properties of blood pressure and heart rate control in suncus.

    Science.gov (United States)

    Matsuki, N; Sakuma, Y; Saito, H

    1993-05-01

    Blood pressure and heart rate and responses to various physiological substances in suncus were characterized and compared with those in mice. The blood pressures of the two species were similar, but the heart rate of suncus (about 400 beat/min) was significantly lower than that of mice. Norepinephrine increased the blood pressure but decreased the heart rate in suncus. The latter was blocked by cervical vagotomy. Sensitivities to acetylcholine and isoproterenol were lower in suncus. These results suggest that regulation of blood pressure and heart rate in suncus is very unique and different from the well-defined system of the rodents. PMID:8341030

  5. Rate Control Management of Atrial Fibrillation: May a Mathematical Model Suggest an Ideal Heart Rate?

    CERN Document Server

    Anselmino, Matteo; Camporeale, Carlo; Saglietto, Andrea; Gaita, Fiorenzo; Ridolfi, Luca

    2015-01-01

    Background. Despite the routine prescription of rate control therapy for atrial fibrillation (AF), clinical evidence demonstrating a heart rate target is lacking. Aim of the present study was to run a mathematical model simulating AF episodes with a different heart rate (HR) to predict hemodynamic parameters for each situation. Methods. The lumped model, representing the pumping heart together with systemic and pulmonary circuits, was run to simulate AF with HR of 50, 70, 90, 110 and 130 bpm, respectively. Results. Left ventricular pressure increased by 56.7%, from 33.92+-37.56 mmHg to 53.15+-47.56 mmHg, and mean systemic arterial pressure increased by 27.4%, from 82.66+-14.04 mmHg to 105.29+-7.63 mmHg, at the 50 and 130 bpm simulations, respectively. Stroke volume (from 77.45+-8.5 to 39.09+-8.08 mL), ejection fraction (from 61.1+-4.4 to 39.32+-5.42%) and stroke work (SW, from 0.88+-0.04 to 0.58+-0.09 J) decreased by 49.5, 35.6 and 34.2%, at the 50 and 130 bpm simulations, respectively. In addition, oxygen co...

  6. Heart Rate Variability in Patients with Chronic Obstructive Pulmonary Disease Treated by Noninvasive Mechanic Ventilation

    Directory of Open Access Journals (Sweden)

    Zekeriya Küçükdurmaz

    2011-08-01

    Full Text Available Aims: This study aimed to investigate heart rate variability (HRV of patients with severe COPD who are treated by noninvasive mechanic ventilation (NIMV.Patients and Method: Twenty-seven patient (58±8 years, 9 F with severe COPD treated by nocturnal NIMV at home and 23 sex and age matched volunteers (56±8 years, 11 F who has not dyspnea as a control group recruited in the study. Subjects underwent spirometry, blood gas analysis, transthoracic echocardiography, 24 hours ambulatory ECG analysis. Time domain HRV analysis performed from ambulatory ECG records. Results: 52% of patients at NYHA functional class II, 36% at class III, and 12% at class IV when they have been treated by NIMV. Groups were similar for age and sex (p>0.05 for both. Heart rates of patients were higher significantly than controls’ (p0.05. But, systolic pulmonary pressures were higher of COPD group (p<0.01. 24 hours heart rate was higher, and standard deviation of normal R-R intervals (SDNN 24 hours, SDNN night, SDNN day, SDNN index (SDNNI and standard deviation of mean R-R intervals (SDANNI values were lower in COPD group significantly. SDNN was inversely correlated with duration of daily NIMV usage, intensive care unit administration and entubation rate and PaCO2. SDNNI was inversely correlated with functional class, duration of daily NIMV usage, intensive care unit administration rate and PaCO2. Else, SDNNI was correlated with predicted forced vital capacity % (FVC% and predicted forced expiratory volume at 1 second % (FEV1%.Conclusion: Time domain HRV decreases in patients with severe COPD. Decrease is correlated with severity of disease, and it presents in despite of the chronic nocturnal NIMV application. These patients have high risk for cardiovascular morbidity and mortality and should be monitored and manegement for cardiovascular events.

  7. Heart rate variability analysis during central hypovolemia using wavelet transformation.

    Science.gov (United States)

    Ji, Soo-Yeon; Belle, Ashwin; Ward, Kevin R; Ryan, Kathy L; Rickards, Caroline A; Convertino, Victor A; Najarian, Kayvan

    2013-06-01

    Detection of hypovolemia prior to overt hemodynamic decompensation remains an elusive goal in the treatment of critically injured patients in both civilian and combat settings. Monitoring of heart rate variability has been advocated as a potential means to monitor the rapid changes in the physiological state of hemorrhaging patients, with the most popular methods involving calculation of the R-R interval signal's power spectral density (PSD) or use of fractal dimensions (FD). However, the latter method poses technical challenges, while the former is best suited to stationary signals rather than the non-stationary R-R interval. Both approaches are also limited by high inter- and intra-individual variability, a serious issue when applying these indices to the clinical setting. We propose an approach which applies the discrete wavelet transform (DWT) to the R-R interval signal to extract information at both 500 and 125 Hz sampling rates. The utility of machine learning models based on these features were tested in assessing electrocardiogram signals from volunteers subjected to lower body negative pressure induced central hypovolemia as a surrogate of hemorrhage. These machine learning models based on DWT features were compared against those based on the traditional PSD and FD, at both sampling rates and their performance was evaluated based on leave-one-subject-out fold cross-validation. Results demonstrate that the proposed DWT-based model outperforms individual PSD and FD methods as well as the combination of these two traditional methods at both sample rates of 500 Hz (p value <0.0001) and 125 Hz (p value <0.0001) in detecting the degree of hypovolemia. These findings indicate the potential of the proposed DWT approach in monitoring the physiological changes caused by hemorrhage. The speed and relatively low computational costs in deriving these features may make it particularly suited for implementation in portable devices for remote monitoring. PMID:23371800

  8. A comparison between computer-controlled and set work rate exercise based on target heart rate

    Science.gov (United States)

    Pratt, Wanda M.; Siconolfi, Steven F.; Webster, Laurie; Hayes, Judith C.; Mazzocca, Augustus D.; Harris, Bernard A., Jr.

    1991-01-01

    Two methods are compared for observing the heart rate (HR), metabolic equivalents, and time in target HR zone (defined as the target HR + or - 5 bpm) during 20 min of exercise at a prescribed intensity of the maximum working capacity. In one method, called set-work rate exercise, the information from a graded exercise test is used to select a target HR and to calculate a corresponding constant work rate that should induce the desired HR. In the other method, the work rate is controlled by a computer algorithm to achieve and maintain a prescribed target HR. It is shown that computer-controlled exercise is an effective alternative to the traditional set work rate exercise, particularly when tight control of cardiovascular responses is necessary.

  9. The art equipment for measuring the horse’s heart rate

    Directory of Open Access Journals (Sweden)

    F. Cus

    2010-07-01

    Full Text Available Purpose: of this paper: Heart rate is a reliable indicator of the stress. Non-invasive methods have advantage over the methods that have a negative influence on the condition of an animal. When breeding sport horses, which undergo stressful training every day, it is required, from an ethical aspect, to monitor their capabilities by using most advanced electronic devices Polar Sport Tester and Polar Equine RS800cx G3.Design/methodology/approach: The original Polar ProTrainer 5 Equine edition software facilitates the analysis of individual training phases and gives the number of heart beats, average heart rate, average speed and distance covered in individual training phases.Findings: Heart rate increased, in warming up phase, from the value associated with a resting horse (30 to 40 bpm approximately in one minute, while, during the slow cooling down phase, ten minutes were required for the heart rate to reach the afore-mentioned value. During quick trotting heart rate are 112 heart beats per minute, while during steeplechase phase, it increased to the value of 160 to 170 heart beats per minute.Research limitations/implications: To receive heart rate without disturbances already we moisten the skin on the contact spots, using a mixture of water and electrolytes (Salvana Nutrilyt. Placing receiver on the saddle close by the T56H transmitter was the optimal choice.Practical implications: Modern equipment makes monitoring the horse’s heart rate accurately and to perform, safely and without disturbances, exercises required during training. It also checks the heart rate, which indicates the horse’s health.Originality/value: Polar Sport Tester and Polar Equine RS800cx G3 are state of the art products that facilitate the receipt of the horse’s heart rate signals. The accuracy of the acquired results can be compared with those obtained with ECG measurements.

  10. Combined effects of depressive symptoms and resting heart rate on mortality: the Whitehall II prospective cohort study. : Depression, Resting Heart Rate and Mortality

    OpenAIRE

    Nabi, Hermann; Kivima?ki, Mika; Empana, Jean-philippe; Sabia, Se?verine; Britton, Annie; Marmot, Michael; Shipley, Martin; Singh-manoux, Archana

    2011-01-01

    OBJECTIVE: To examine the combined effects of depressive symptoms and resting heart rate on mortality risk. METHOD: Analysis was performed on data from 5,936 participants in the Whitehall II study with a mean ± SD age of 61 ± 6 years. Depressive symptoms were assessed from 2002 to 2004 using the Center for Epidemiologic Studies Depression Scale (cutoff score for depression at ? 16). Resting heart rate was measured at the same study phase via electrocardiogram. Participants were assigned t...

  11. Effect of dietary omega-3 fatty acids on the heart rate and the heart rate variability responses to myocardial ischemia or submaximal exercise

    OpenAIRE

    Billman, George E.; Harris, William S.

    2011-01-01

    The consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) has been reported to decrease resting heart rate (HR) and increase heart rate variability (HRV). However, the effects of n-3 PUFAs on these variables in response to a physiological stress (e.g., exercise or acute myocardial ischemia), particularly in postmyocardial infarction (MI) patients, are unknown. Therefore, HR and HRV (high frequency and total R-R interval variability) were evaluated at rest, during submaximal exercise,...

  12. Target heart rate to determine the normal value of coronary flow reserve during dobutamine stress echocardiography

    Directory of Open Access Journals (Sweden)

    Rousse Maria G

    2011-04-01

    Full Text Available Abstract Background The determination of coronary flow reserve (CFR is an essential concept at the moment of decision-making in ischemic heart disease. There are several direct and indirect tests to evaluate this parameter. In this sense, dobutamine stress echocardiography is one of the pharmacological method most commonly used worldwide. It has been previously demonstrated that CFR can be determined by this technique. Despite our wide experience with dobutamine stress echocardiography, we ignored the necessary heart rate to consider sufficient the test for the analysis of CFR. For this reason, our main goal was to determine the velocity of coronary flow in each stage of dobutamine stress echocardiography and the heart rate value necessary to double the baseline values of coronary flow velocity in the territory of the left anterior descending (LAD coronary artery. Methods A total of 33 consecutive patients were analyzed. The patients included had low risk for coronary artery disease. All the participants underwent dobutamine stress echocardiography and coronary artery flow velocity was evaluated in the distal segment of LAD coronary artery using transthoracic color-Doppler echocardiography. Results The feasibility of determining CFR in the territory of the LAD during dobutamine stress echocardiography was high: 31/33 patients (94%. Mean CFR was 2.67 at de end of dobutamine test. There was an excellent concordance between delta HR (difference between baseline HR and maximum HR and the increase in the CFR (correlation coefficient 0.84. In this sense, we found that when HR increased by 50 beats, CFR was ? 2 (CI 93-99.2%. In addition, 96.4% of patients reached a CFR ? 2 (IC 91.1 - 99% at 75% of their predicted maximum heart rate. Conclusions We found that the feasibility of dobutamine stress echocardiography to determine CFR in the territory of the LAD coronary artery was high. In this study, it was necessary to achieve a difference of 50 bpm from baseline HR or at least 75% of the maximum predicted heart rate to consider sufficient the test for the analysis of CFR.

  13. Normative references of heart rate variability and salivary alpha-amylase in a healthy young male population

    Directory of Open Access Journals (Sweden)

    Kobayashi Hiromitsu

    2012-04-01

    Full Text Available Abstract Background This study aimed to present normative reference values of heart rate variability and salivary alpha-amylase in a healthy young male population with a particular focus on their distribution and reproducibility. Methods The short-term heart rate variability of 417 young healthy Japanese men was studied. Furthermore, salivary alpha-amylase was measured in 430 men. The average age of the subjects were 21.9 years with standard deviation of 1.6 years. Interindividual variations in heart rate variability indices and salivary alpha-amylase levels were plotted as histograms. Data are presented as the mean, median, standard deviation, coefficient of variation, skewness, kurtosis, and fifth and 95th percentiles of each physiological index. Results Mean recorded values were heart period 945.85 ms, log-transformed high frequency component 9.84 ln-ms2, log-transformed low frequency component 10.42 ln-ms2, log-transformed low frequency to high frequency ratio 0.58 ln-ratio, standard deviation of beat-to-beat interval 27.17 ms and root mean square of successive difference 37.49 ms. The mean value of raw salivary alpha-amylase was 17.48 U/mL, square root salivary alpha-amylase 3.96 sqrt[U/mL] and log-transformed salivary alpha-amylase 2.65 ln[U/mL]. Log-transformed heart rate variability indices exhibited almost symmetrical distributions; however, time-domain indices of heart rate variability (standard deviation of beat-to-beat interval and root mean square of successive difference exhibited right-skewed (positive skewness distributions. A considerable right-skewed distribution was observed for raw salivary alpha-amylase. Logarithmic transformation improved the distribution of salivary alpha-amylase, although square root transformation was insufficient. The day-to-day reproducibility of these indices was assessed using intraclass correlation coefficients. Intraclass correlation coefficients of most heart rate variability and salivary indices were approximately 0.5 to 0.6. Intraclass correlation coefficients of raw salivary markers were approximately 0.6, which was similar to those of heart rate variability; however, log transformation of the salivary markers did not considerably improve their reproducibility. Correlations between sympathetic indicators of heart rate variability and salivary alpha-amylase were not observed. Conclusion Because the sample population examined in this study involved limited age and gender variations, the present results were independent of these factors and were indicative of pure interindividual variation.

  14. Decreased nighttime heart rate variability is associated with increased stroke risk

    DEFF Research Database (Denmark)

    Binici, Zeynep; Mouridsen, Mette Rauhe

    2011-01-01

    Prediction of stroke in healthy individuals is challenging and there is a diurnal variation of stroke onset. We hypothesized that heart rate variability with a focus on nighttime heart rate variability will predict the risk of stroke in apparently healthy middle-age and elderly subjects.

  15. Film-type transducer materials PVDF and EMFi in the measurement of heart and respiration rates.

    Science.gov (United States)

    Kärki, Satu; Lekkala, Jukka

    2008-01-01

    Film-type transducer materials polyvinylidenefluoride (PVDF) and ElectroMechanical Film (EMFi) were used in the measurement of heart and respiration rates on the chest wall at rest. The aim here was to evaluate if the both materials are capable to measure the heart and respiration rates correctly and also to found out if there are differences between the results of PVDF and EMFi. The movements provided by the pulsation of heart and respiration were converted into an electrical signal by the sensors. The signals were amplified and transmitted to a computer. The data was analyzed with Matlab software. The signals were filtered to reveal the heart pulsation and respiration components. Power spectral density (PSD) spectrum was computed to determine the heart and respiration rates. ECG was used as a reference signal for the heart rate and a thermistor for the respiration rate. Both transducer materials provided good results and no differences between PVDF and EMFi were found. The heart rates measured with PVDF and EMFi sensors corresponded to the values calculated from the ECG signal. Also the respiration rates correlated with the values determined with the thermistor. To conclude, both materials provided reliable results in the measurements of heart and respiration rates. PMID:19162710

  16. Heart Rate and Treatment Effect in Children with Disruptive Behavior Disorders

    Science.gov (United States)

    Stadler, Christina; Grasmann, Dorte; Fegert, Jorg M.; Holtmann, Martin; Poustka, Fritz; Schmeck, Klaus

    2008-01-01

    Objective: To examine whether children with disruptive behavior disorders (DBDs; hyperkinetic conduct disorder, conduct disorder, hyperkinetic disorder) characterized by low heart rate profit less from an intensive cognitive behavioral intervention aimed at reducing impulsive, oppositional and aggressive behavior problems. Method: Basal heart rate

  17. 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…

  18. SKIPPING BREAKFAST: GENDER EFFECTS ON RESTING HEART RATE MEASURES IN PREADOLESCENTS

    Science.gov (United States)

    The cardiovascular response in children to morning nutrition has received little attention, and associated gender-related effects are virtually uninvestigated. This study evaluated resting heart-rate (HR) and heart-rate variability (HRV) in preadolescents after overnight fasting and again after eati...

  19. Associations of resting heart rate with insulin resistance, cardiovascular events and mortality in chronic kidney disease

    OpenAIRE

    Beddhu, Srinivasan; Nigwekar, Sagar U.; Ma, Xilulian; Greene, Tom

    2009-01-01

    Background. Insulin resistance is associated with increased sympathetic and reduced parasympathetic activity. Resting heart rate reflects autonomic activity. Therefore, we examined the associations of resting heart rate with insulin resistance, cardiovascular events and mortality in the moderate chronic kidney disease (CKD) population.

  20. The Influence of Motor Impairment on Autonomic Heart Rate Modulation among Children with Cerebral Palsy

    Science.gov (United States)

    Zamuner, Antonio Roberto; Cunha, Andrea Baraldi; da Silva, Ester; Negri, Ana Paola; Tudella, Eloisa; Moreno, Marlene Aparecida

    2011-01-01

    The study of heart rate variability is an important tool for a noninvasive evaluation of the neurocardiac integrity. The present study aims to evaluate the autonomic heart rate modulation in supine and standing positions in 12 children diagnosed with cerebral palsy and 16 children with typical motor development (control group), as well as to…

  1. Peak flow rate and death due to coronary heart disease: 30-year results from the Northwick Park Heart cohort study

    Science.gov (United States)

    Clayton, Tim C; Meade, Tom W; Turner, Elizabeth L; De Stavola, Bianca L

    2014-01-01

    Objective Numerous studies have reported that chronic obstructive pulmonary disease or impaired lung function are associated with later coronary heart disease (CHD). However, it is unclear if lung function is an independent risk factor, as many of these studies have included only limited measures of other factors associated with CHD. Methods In total 2167 men of all ages in the first Northwick Park Heart Study were followed for a median of 30?years. Cox regression models were used to assess the relationship between peak flow rate (PFR) and CHD mortality adjusted for potential confounders measured at baseline. Analyses allowed for missing data, and secondary analyses for repeat measures on some men and competing risks of CHD death. Results There were 254 CHD deaths with some evidence of an association between PFR and CHD mortality. The adjusted HRs (95% CIs) from the lowest to the highest of four PFR quartiles were 1.53 (1.04 to 2.25), <430?L/min; 1.43 (0.99 to 2.08), 430 – <490?L/min; and 1.31 (0.93 to 1.86), 490 – <550?L/min; compared with the reference group of ?550?L/min (trend test p=0.025). Other associations with CHD mortality were observed for systolic blood pressure (p<0.0001), body mass index (p=0.0002), smoking status (p=0.015), blood cholesterol (p=0.005), plasma fibrinogen (p=0.001) and high-risk ECG (p=0.021). There were no strong associations for factors V and VIII or platelet count. Conclusions After allowing for a range of other risk factors associated with CHD, there was only limited evidence of a relation between PFR and CHD mortality. PMID:25332831

  2. Extraction of heart rate variability from smartphone photoplethysmograms.

    Science.gov (United States)

    Peng, Rong-Chao; Zhou, Xiao-Lin; Lin, Wan-Hua; Zhang, Yuan-Ting

    2015-01-01

    Heart rate variability (HRV) is a useful clinical tool for autonomic function assessment and cardiovascular diseases diagnosis. It is traditionally calculated from a dedicated medical electrocardiograph (ECG). In this paper, we demonstrate that HRV can also be extracted from photoplethysmograms (PPG) obtained by the camera of a smartphone. Sixteen HRV parameters, including time-domain, frequency-domain, and nonlinear parameters, were calculated from PPG captured by a smartphone for 30 healthy subjects and were compared with those derived from ECG. The statistical results showed that 14 parameters (AVNN, SDNN, CV, RMSSD, SDSD, TP, VLF, LF, HF, LF/HF, nLF, nHF, SD1, and SD2) from PPG were highly correlated (r > 0.7, P good agreement with those from ECG within the acceptable limits. In addition, five different algorithms to detect the characteristic points of PPG wave were also investigated: peak point (PP), valley point (VP), maximum first derivative (M1D), maximum second derivative (M2D), and tangent intersection (TI). The results showed that M2D and TI algorithms had the best performance. These results suggest that the smartphone might be used for HRV measurement. PMID:25685174

  3. Muscle metaboreflex and autonomic regulation of heart rate in humans

    DEFF Research Database (Denmark)

    Fisher, James P; Adlan, Ahmed M

    2013-01-01

    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), ?1-adrenergic blockade (metoprolol) and parasympathetic blockade (glycopyrrolate) conditions. HR increased with partial flow restriction during leg cycling in the control condition (11 ± 2 beats min(-1); P 0.05 between conditions). During PEI following handgrip, HR was similarly elevated from rest under control and parasympathetic blockade (4 ± 1 vs. 4 ± 2 beats min(-1); P > 0.05 between conditions) conditions, but attenuated with ?-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 cycling) is there a contribution from the partial withdrawal of cardiac parasympathetic tone.

  4. Increased heart rate and atherosclerosis: Potential implications of ivabradine therapy

    Directory of Open Access Journals (Sweden)

    Alberto Dominguez-Rodriguez

    2011-04-01

    Full Text Available Despite all the therapeutic advances in the field of cardiology, cardiovascular diseases, and in particular coronary artery disease, remain the leading cause of death and disability worldwide, thereby underlining the importance of acquiring new therapeutic options in this field. A reduction in elevated resting heart rate (HR has long been postulated as a therapeutic approach in the management of cardiovascular disease. An increased HR has been shown to be associated with increased progression of coronary atherosclerosis in animal models and patients. A high HR has also been associated with a greatly increased risk of plaque rupture in patients with coronary atherosclerosis. Endothelial function may be an important link between HR and atherosclerosis. An increased HR has been shown experimentally to cause endothelial dysfunction. Inflammation plays a significant role in the pathogenesis and progression of atherosclerosis. In the literature, there is data that shows an association between HR and circulating markers of vascular inflammation. In addition, HR reduction by pharmacological intervention with ivabradine (a selective HR-lowering agent that acts by inhibiting the pacemaker ionic current If in sinoatrial node cells reduces the formation of atherosclerotic plaques in animal models of lipid-induced atherosclerosis. The aim of this editorial is to review the possible role of ivabradine on atherosclerosis.

  5. Entertainment Capture through Heart Rate Activity in Physical Interactive Playgrounds

    DEFF Research Database (Denmark)

    Yannakakis, Georgios; Hallam, John

    2008-01-01

    An approach for capturing and modeling individual entertainment (“fun”) preferences is applied to users of the innovative Playware playground, an interactive physical playground inspired by computer games, in this study. The goal is to construct, using representative statistics computed from 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 implemented on the Playware playground. A comprehensive statistical analysis shows that children’s reported entertainment preferences correlate well with specific features of the HR signal. Neuro-evolution techniques combined with feature set selection methods permit the construction of user models 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% of cases on previously unseen data (p?value 6 · 10?5). The generality of the methodology, its limitations, its usability as a real-time feedback mechanism for entertainment augmentation and as a validation tool are discussed. Udgivelsesdato: February

  6. Effect of Wireless Network Radiation on Heart Rate Variability

    Directory of Open Access Journals (Sweden)

    Barjinder Singh Saini

    2014-01-01

    Full Text Available The health risk associated with the increased exposure to wireless network devices like Mobile Phones, Wi-Fi etc, had been area of concern. In this paper, the effects of wireless network radiations (WNR on Heart Rate Variability (HRV had been investigated. The two non-linear indices namely i Approximate Entropy (ApEn ii Detrended Fluctuation Analysis (DFA had been used for deciphering the hidden dynamics of HRV. The study comprised of 19 healthy male subjects in the age group of 23±4.3 (mean ± std dev years. The Electrocardiogram (ECG of each subject obtained under three different WNR exposure modes namely i Least or minimum exposure: when WNR level is 0.49±0.12 mW/m2 ii Moderate exposure: when WNR level is 2.08±0.27 mW/m2 iii Maximum or calling mode exposure: when WNR level is 1.65±0.32 W/m2. The results indicate that there is a significant increase in DFA scaling exponent when the WNR level changed from minimum to maximum value, as p-value <0.05, whereas the change in mean value of ApEn was not significant due to higher standard deviation among all the subjects. The WNR exposure caused changes in HRV indices and it varied with WNR level, but all the changes cannot be considered as p values were higher.

  7. On heart rate regulation in cycle-ergometer exercise.

    Science.gov (United States)

    Argha, Ahmadreza; Su, Steven W; Lee, Sangwon; Nguyen, Hung; Celler, Branko G

    2014-01-01

    In this paper, we have focused on the issue of regulating the human heart rate (HR) to a predefined reference trajectory, especially for cycle-ergometer exercise used for training or rehabilitation. As measuring HR is relatively easy compared to exercise intensity, it has been used in the wide range of training programs. The aim of this paper is to develop a non-model-based control strategy using proportional, integral and derivative (PID) controller/relay controller to regulate the HR to track a desired trajectory. In the case of using PID controller, the controller output signal is interpreted as a voice or auditory command, referred to as biofeedback, which can be heard by the exercising subject as a part of the control-loop. Alternatively, the relay controller output signals can be converted to some special words which can be recognised by the exerciser. However, in both cases, to effectively communicate to the user a change in exercise intensity, the timing of this feedback signal relative to the positions of the pedals becomes quite critical. A feedback signal delivered when the pedals are not in a suitable position to efficiently exert force may be ineffective and may lead to a cognitive disengagement of the user form the feedback controller. In this paper we examine the need and the consequence of synchronising the delivery of the feedback signal with an optimal and user specific placement of the pedal. PMID:25570718

  8. Does Baseline Heart Rate Variability Reflect Stable Positive Emotionality?

    Science.gov (United States)

    Silvia, Paul J; Jackson, Bryonna A; Sopko, Rachel S

    2014-11-01

    Several recent studies have found significant correlations, medium in effect size, between baseline heart rate variability (HRV) and measures of positive functioning, such as extraversion, agreeableness, and trait positive affectivity. Other research, however, has suggested an optimal level of HRV and found nonlinear effects. In the present study, a diverse sample of 239 young adults completed a wide range of measures that reflect positive psychological functioning, including personality traits, an array of positive emotions (measured with the Dispositional Positive Emotions Scale), and depression, anxiety, and stress symptoms (measured with the DASS and CESD). HRV was measured with a 6-minute baseline period and quantified using many common HRV metrics (e.g., respiratory sinus arrhythmia, root mean square of successive differences, and others), and potentially confounding behavioral and lifestyle variables (e.g., BMI, caffeine and nicotine use, sleep quality) were assessed. Neither linear nor non-linear effects were found, and the effect sizes were small and near zero. The findings suggest that the cross-sectional relationship between HRV and positive experience deserves more attention and meta-analytic synthesis. PMID:25147421

  9. Harmful Effects of Mobile Phone Waves on Human Heart Beat Rate

    Directory of Open Access Journals (Sweden)

    Mushtaq Ahmed Bhat,

    2013-08-01

    Full Text Available Concern about human exposure to radiofrequency (RF is not new. The conveniences and satisfaction derived in the use of GSM mobile phone is being threatened by claims of adverse effects on human health by radiation coming from this device. This radiation belongs to the type called non-ionizing radiation the health hazard of which remains debatable. Research has not been carried out on possible effect this device might have on human health and no experimental proof, based on data obtained within India, exist to substantiate any claim. Safety standards exist for radiation from cell phone but these are not reassuring. This paper investigates any possible effect of mobile phone radiation on human heart rate and then come out with conclusion based on experimental proof. Over forty human subjects twenty male and twenty female were monitored by measuring their pulse rate under three exposure criteria. In one of the radiation tests, the phone used was put in vibration mode in order to determine subjects were not just responding to vibration. It was found out pulse rate do not change significantly when subjects were exposed to phone radiation. However, the percentage decrease recorded by people of age 40 years and above, even though barely above 1% makes it advisable that people of age 40 years and above should avoid keeping mobile phones close to the heart.

  10. Diagnostic accuracy of dual-source CT coronary angiography: The effect of average heart rate, heart rate variability, and calcium score in a clinical perspective

    International Nuclear Information System (INIS)

    Background: Dual-source CT coronary angiography (CTCA) has been used to detect coronary artery disease; however, the factors with potential to affect its diagnostic accuracy remain to be defined. Purpose: To prospectively evaluate the accuracy of dual-source CTCA in diagnosing coronary artery stenosis according to conventional coronary angiography (CAG), and the effect of average heart rate, heart rate variability, and calcium score on the accuracy of CTCA. Material and Methods: A total of 113 patients underwent both dual-source CTCA and CAG. The results were used to evaluate the findings in dual-source CTCA to assess the accuracy in the diagnosis of =50% (significant stenosis) and >75% (severe stenosis) of coronary artery according to those by CAG. Patients were divided into subgroups according to their heart rate (HR), HR variability (HRV), and calcium score, and the accuracy of CTCA was further evaluated. The chi-square test was used to analyze the difference in sensitivity and specificity for the detection of =50% and >75% coronary stenosis among subgroups. The generalized estimation equation method was used in per-vessel analysis to adjust for within-patient correlation. Results: In all, 113 patients had 338 vessels and 1661 segments evaluated by CAG. Dual-source CTCA displayed 1527 segments (91.9%). Among them, 1468 segments (calcium score by CAG score 1, n=1018; score 2, n=270; score 3, n=180) were assessable in CTCA. On a per-patient analysis, the sensitivity n a per-patient analysis, the sensitivity and specificity of CTCA were 93.9% and 93.5% for significant stenosis and 86.9% and 98.1% for severe stenosis. On a per-vessel basis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. On a per-segment analysis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. Average HR had no effect on the sensitivity and specificity of CTCA (P>0.05); whereas HRV and calcium score had some effect on the sensitivity and specificity of CTCA (P<0.05). Conclusion: On a per-patient, per-vessel, and per-segment basis, dual-source CTCA has a high sensitivity and specificity for the diagnosis of coronary artery stenosis. Average HR has no effect on the diagnostic accuracy of CTCA, while HRV and calcium score have a statistically significant effect on the sensitivity and specificity of CTCA

  11. Diagnostic accuracy of dual-source CT coronary angiography: The effect of average heart rate, heart rate variability, and calcium score in a clinical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Long-Jiang Zhang; Zhuo-Li Zhang; Chang-Sheng Zhou; Guang-Ming Lu (Dept. of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing Univ., Nanjing (China)), e-mail: cjr.luguangming@vip.163.com; Sheng-Yong Wu (Medical Imaging Inst. of Tianjin, Tianjin (China)); Jing Wang; Shi-Sen Jiang (Dept. of Cardiology, Jinling Hospital, Clinical School of Medical College, Nanjing Univ., Nanjing (China)); Ying Lu (Dept. of Radiology and Biomedical Imaging, Univ. of California, San Francisco, CA (United States))

    2010-09-15

    Background: Dual-source CT coronary angiography (CTCA) has been used to detect coronary artery disease; however, the factors with potential to affect its diagnostic accuracy remain to be defined. Purpose: To prospectively evaluate the accuracy of dual-source CTCA in diagnosing coronary artery stenosis according to conventional coronary angiography (CAG), and the effect of average heart rate, heart rate variability, and calcium score on the accuracy of CTCA. Material and Methods: A total of 113 patients underwent both dual-source CTCA and CAG. The results were used to evaluate the findings in dual-source CTCA to assess the accuracy in the diagnosis of =50% (significant stenosis) and >75% (severe stenosis) of coronary artery according to those by CAG. Patients were divided into subgroups according to their heart rate (HR), HR variability (HRV), and calcium score, and the accuracy of CTCA was further evaluated. The chi-square test was used to analyze the difference in sensitivity and specificity for the detection of =50% and >75% coronary stenosis among subgroups. The generalized estimation equation method was used in per-vessel analysis to adjust for within-patient correlation. Results: In all, 113 patients had 338 vessels and 1661 segments evaluated by CAG. Dual-source CTCA displayed 1527 segments (91.9%). Among them, 1468 segments (calcium score by CAG score 1, n=1018; score 2, n=270; score 3, n=180) were assessable in CTCA. On a per-patient analysis, the sensitivity and specificity of CTCA were 93.9% and 93.5% for significant stenosis and 86.9% and 98.1% for severe stenosis. On a per-vessel basis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. On a per-segment analysis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. Average HR had no effect on the sensitivity and specificity of CTCA (P>0.05); whereas HRV and calcium score had some effect on the sensitivity and specificity of CTCA (P<0.05). Conclusion: On a per-patient, per-vessel, and per-segment basis, dual-source CTCA has a high sensitivity and specificity for the diagnosis of coronary artery stenosis. Average HR has no effect on the diagnostic accuracy of CTCA, while HRV and calcium score have a statistically significant effect on the sensitivity and specificity of CTCA

  12. Chaotic Behavior of Heart Rate Signals during Chi and Kundalini Meditation

    Directory of Open Access Journals (Sweden)

    Atefeh Goshvarpour

    2012-03-01

    Full Text Available Nonlinear dynamics has been introduced to the analysis of biological data and increasingly recognized to be functionally relevant. The aim of this study is to quantify and compare the contribution of nonlinear and chaotic dynamics of human heart rate variability during two forms of meditation: (i Chinese Chi (or Qigong meditation and (ii Kundalini Yoga meditation. For this purpose, Poincare plots, Lyapunov exponents and Hurst exponents of heart rate variability signals were analyzed. In this study, we examined the different behavior of heart rate signals during two specific meditation techniques. The results show that heart rate signals became more periodic and their chaotic behavior was decreased in both techniques of meditation. Therefore, nonlinear chaotic indices may serve as a quantitative measure for psychophysiological states such as meditation. In addition, different forms of meditation appear to differentially alter specific components of heart rate signals.

  13. A new method to measure heart rate with EMFi and PVDF materials.

    Science.gov (United States)

    Kärki, S; Lekkala, J

    2009-01-01

    In this paper we propose a new simple method to measure the heart rate of a person sitting on a chair or lying in a bed. The heart rate is measured with a thin sensor pad consisting of separate electromechanical film (EMFi) and polyvinylidenefluoride (PVDF) transducers located beneath the leg of chair or bed. This study aims to evaluate the operation of the sensor system with measurements, and also to compare the results provided by the two transducer materials. Based on the results obtained here, the heart rates measured with the transducers mainly corresponded to the values of reference ECG signal. Some minor differences between the heart rate values of PVDF and EMFi appeared, especially in supine position, possible due to the material sensitivities to different force directions. However, to conclude, both materials seem to be convenient for this kind of measurement of heart rate. PMID:19591050

  14. Reduction of Heart Rate by Omega-3 Fatty Acids and the Potential Underlying Mechanisms

    Directory of Open Access Journals (Sweden)

    JingXuanKang

    2012-10-01

    Full Text Available An elevated resting heart rate is one of the strongest predictors of cardiovascular mortality and is independently associated with sudden cardiac death (SCD. Agents capable of reducing heart rate without significant side effects are therefore of particular interest for the prevention of SCD. Recent human and animal studies have shown that omega-3 fatty acids can reduce heart rate. Our work has shown that omega-3 fatty acids significantly reduce membrane electrical excitability of the cardiac myocyte by lowering its resting membrane potential and the duration of the refractory period through inhibition of ion channels. We propose that these actions may be the underlying mechanisms for the omega-3 fatty acid-induced reduction of heart rate observed in both humans and animals. The heart rate-lowering capability of omega-3 fatty acids may contribute to their preventive effect against SCD.

  15. Prognostic Value of Ambulatory Heart Rate Revisited in 6928 Subjects From 6 Populations.

    DEFF Research Database (Denmark)

    Hansen, Tine Willum; Thijs, Lutgarde

    2008-01-01

    The evidence relating mortality and morbidity to heart rate remains inconsistent. We performed 24-hour ambulatory blood pressure monitoring in 6928 subjects (not on ?-blockers; mean age: 56.2 years; 46.5% women) enrolled in prospective population studies in Denmark, Belgium, Japan, Sweden, Uruguay, and China. We computed standardized hazard ratios for heart rate, while stratifying for cohort, and adjusting for blood pressure and other cardiovascular risk factors. Over 9.6 years (median), 850, 325, and 493 deaths accrued for total, cardiovascular, and noncardiovascular mortality, respectively. The incidence of fatal combined with nonfatal end points was 805, 363, 439, and 324 for cardiovascular, stroke, cardiac, and coronary events, respectively. Twenty-four-hour heart rate predicted total (hazard ratio: 1.15) and noncardiovascular (hazard ratio: 1.18) mortality but not cardiovascular mortality (hazard ratio: 1.11) or any of the fatal combined with nonfatal events (hazard ratio: 1.02). Daytime heart rate did not predict mortality (hazard ratio: 1.11) or any fatal combined with nonfatal event (hazard ratio: 0.96). Nighttime heart rate predicted all of the mortality outcomes (hazard ratio: 1.15) but none of the fatal combined with nonfatal events (hazard ratio: 1.11). The night:day heart rate ratio predicted total (hazard ratio: 1.14) and noncardiovascular mortality (hazard ratio: 1.12) and all of the fatal combined with nonfatal events (hazard ratio: 1.15) with the exception of stroke (hazard ratio: 1.06). Sensitivity analyses, in which we stratified by risk factors or from which we excluded 1 cohort at a time or the events occurring within 2 years of enrollment, showed consistent results. In the general population, heart rate predicts total and noncardiovascular mortality. With the exception of the night:day heart rate ratio, heart rate did not add to the risk stratification for fatal combined with nonfatal cardiovascular events. Thus, heart rate adds little to the prediction of cardiovascular risk.

  16. Blood Pressure and Heart Rate Alterations through Music in Patients Undergoing Cataract Surgery in Greece

    Science.gov (United States)

    Merakou, Kyriakoula; Varouxi, Georgia; Barbouni, Anastasia; Antoniadou, Eleni; Karageorgos, Georgios; Theodoridis, Dimitrios; Koutsouri, Aristea; Kourea-Kremastinou, Jenny

    2015-01-01

    INTRODUCTION Music has been proposed as a safe, inexpensive, nonpharmacological antistress intervention. The purpose of this study was to determine whether patients undergoing cataract surgery while listening to meditation music experience lower levels of blood pressure and heart rate. METHODS Two hundred individuals undergoing cataract surgery participated in the study. Hundred individuals listened to meditation music, through headphones, before and during the operation (intervention group) and 100 individuals received standard care (control group). Patients stress coping skills were measured by the Sense of Coherence Scale (SOC Scale). Systolic and diastolic blood pressure and heart rate were defined as outcome measures. RESULTS According to the SOC Scale, both groups had similar stress coping skills (mean score: 127.6 for the intervention group and 127.3 for the control group). Before entering the operating room (OR) as well as during surgery the rise in systolic and diastolic pressures was significantly lower in the intervention group (P < 0.001). Among patients receiving antihypertensive therapy, those in the intervention group presented a lower increase only in systolic pressure (P < 0.001) at both time recordings. For those patients in the intervention group who did not receive antihypertensive treatment, lower systolic blood pressure at both time recordings was recorded (P < 0.001) while lower diastolic pressure was observed only during entry to the OR (P = 0.021). Heart rate was not altered between the two groups in any of the recordings. CONCLUSIONS Meditation music influenced patients’ preoperative stress with regard to systolic blood pressure. This kind of music can be used as an alternative or complementary method for blood pressure stabilizing in patients undergoing cataract surgery.

  17. Assessment of baroreflex sensitivity from spontaneous oscillations of blood pressure and heart rate: proven clinical value?

    Science.gov (United States)

    Pinna, Gian Domenico; Maestri, Roberto; La Rovere, Maria Teresa

    2015-04-01

    The baroreceptor-heart rate reflex (baroreflex sensitivity, BRS) is a key mechanism contributing to the neural regulation of the cardiovascular system. Several methods have been proposed so far to assess BRS by analyzing the spontaneous beat-to-beat fluctuations of arterial blood pressure and heart rate. These methods are inherently simple, non-invasive and low-cost. This study is an attempt to address the question of whether spontaneous baroreflex methods have proven to be of value in the clinical setting. In the first part of this article, we critically review most representative clinical studies using spontaneous BRS techniques either for risk stratification or treatment evaluation, these being major issues in the clinical management of the patients. In the second part, we address two important aspects of spontaneous BRS measurements: measurability and reliability. Estimation of BRS in the studies selected for the review was performed according to the sequence, transfer function, alpha-index and phase-rectified signal averaging method. Arterial blood pressure was recorded non-invasively during supine, short-term (<30 min) laboratory recordings. The conclusion from this review is that spontaneous BRS techniques have been shown to be of great value in clinical practice but further work is needed to confirm the validity of previous findings and to widen the field of clinical applications. Measurability and reliability can be a major issue in the measurement of spontaneous BRS, particularly in some patient populations like post-myocardial infarction and heart failure patents. Main causes of poor measurability are: non-sinus rhythm, a high rate of ectopic beats and the need for recorded time series of RR interval and arterial blood pressure to satisfy the constraints of the different BRS estimation algorithms. As for reliability, within-subject variability is rather high in the measurements of spontaneous BRS and, therefore, should be carefully taken into account when BRS measurements are used to detect treatment effects in individual patients. PMID:25798657

  18. Resting heart rate as a predictor of metabolic dysfunctions in obese children and adolescents

    Directory of Open Access Journals (Sweden)

    Freitas Júnior Ismael F

    2012-01-01

    Full Text Available Abstract Background Recent studies have identified that a higher resting heart rate (RHR is associated with elevated blood pressure, independent of body fatness, age and ethnicity. However, it is still unclear whether RHR can also be applied as a screening for other risk factors, such as hyperglycemia and dyslipidemia. Thus, the purpose of the presented study was to analyze the association between RHR, lipid profile and fasting glucose in obese children and adolescents. Methods The sample was composed of 180 obese children and adolescents, aged between 7-16 years. Whole-body and segmental body composition were estimated by Dual-energy X-ray absorptiometry. Resting heart rate (RHR was measured by heart rate monitors. The fasting blood samples were analyzed for serum triglycerides, total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C, low-density lipoprotein cholesterol (LDL-C, and glucose, using the colorimetric method. Results Fasting glucose, TC, triglycerides, HDL-C, LDL-C and RHR were similar in both genders. The group of obese subjects with a higher RHR presented, at a lower age, higher triglycerides and TC. There was a significant relationship between RHR, triglycerides and TC. In the multivariate model, triglycerides and TC maintained a significant relationship with RHR independent of age, gender, general and trunk adiposity. The ROC curve indicated that RHR has a high potential for screening elevated total cholesterol and triglycerides as well as dyslipidemia. Conclusion Elevated RHR has the potential to identify subjects at an increased risk of atherosclerosis development.

  19. Assessment of autonomic function after acute spinal cord injury using heart rate variability analyses

    DEFF Research Database (Denmark)

    Malmqvist, L; Biering-SØrensen, T

    2015-01-01

    OBJECTIVES: Spinal cord injury (SCI) often results in severe dysfunction of the autonomic nervous system. C1-C8 SCI affects the supraspinal control to the heart, T1-T5 SCI affects the spinal sympathetic outflow to the heart, and T6-T12 SCI leaves sympathetic control to the heart intact. Heart rate variability (HRV) analysis can serve as a surrogate measure of autonomic regulation. The aim of this study was to investigate changes in HRV patterns and alterations in patients with acute traumatic SCI. METHODS: As soon as possible after SCI patients who met the inclusion criteria had 24?h Holter monitoring of their cardiac rhythm, additional Holter monitoring were performed 1, 2, 3 and 4 weeks after SCI. RESULTS: Fifty SCI patients were included. A significant increase in standard deviation of the average normal-to-normal (SDANN) sinus intervals was seen in the first month after injury (P=0.008). The increase was only significant in C1-T5 incomplete patients and in patients who did not experience one or more episodes of cardiac arrest. Significant lower values of Low Frequency Power, Total Power and the Low Frequency over High Frequency ratio were seen in the C1-T5 SCI patients compared with T6-T12 SCI patients. CONCLUSIONS: The rise in SDANN in the incomplete C1-T5 patients could be due to spontaneous functional recovery caused by synaptic plasticity or remodelling of damaged axons. That the autonomic nervous system function differs between C1-C8, T1-T5 and T6-T12 patients suggest that the sympathovagal balance in both the C1-C8 and T1-T5 SCI patients has yet to be reached.

  20. The relationship between heart rate reserve and oxygen uptake reserve in heart failure patients on optimized and non-optimized beta-blocker therapy

    OpenAIRE

    Vitor Oliveira Carvalho; Guilherme Veiga Guimarães; Edimar Alcides Bocchi

    2008-01-01

    BACKGROUND: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exerci...

  1. Prostacyclin can either increase or decrease heart rate depending on the basal state.

    OpenAIRE

    Chiavarelli, M.; Moncada, S.; Mullane, K. M.

    1982-01-01

    1 The influence of the basal heart rate on the change in rate induced by prostacyclin (PGI2) was investigated in beagles anaesthetized with chloralose. 2 In male dogs with a low basal heart rate (less than 100 beats/min) PGI2, in doses up to 0.5 microgram/kg intravenously, induced hypotension and tachycardia. 3 In contrast, PGI2-induced hypotension was accompanied by bradycardia when either the basal heart rate was increased (greater than 130 beats/min) with isoprenaline or nitroprusside, or ...

  2. Low metabolism and inactive lifestyle of a tropical rain forest bird investigated via heart-rate telemetry

    OpenAIRE

    Steiger, Silke S.; Kelley, J. Patrick; Cochran, William W.; Wikelski, Martin

    2009-01-01

    Birds in the lowland tropical rain forest are expected to have low energy turnover. Here, we used heart rate telemetry to estimate nighttime resting metabolic rate (RMR), daily energy expenditure (DEE), and locomotor activity of a small, long?lived tropical rain forest understory bird, the spotted antbird (Hylophylax naevioides). Heart rate was linearly related to oxygen consumption in respirometry measurements that encompassed 96% of heart rates measured in wild birds. Heart rates in the w...

  3. Recuperação da freqüência cardíaca após teste de esforço em esteira ergométrica e variabilidade da freqüência cardíaca em 24 horas em indivíduos sadios Heart rate recovery after treadmill electrocardiographic exercise stress test and 24-hour heart rate variability in healthy individuals

    Directory of Open Access Journals (Sweden)

    Ivana Antelmi

    2008-06-01

    Full Text Available FUNDAMENTO: A recuperação da freqüência cardíaca após o eletrocardiograma de esforço em esteira ergométrica é modulada pelo sistema nervoso autônomo. A análise da variabilidade da freqüência cardíaca (VFC pode fornecer informações valiosas sobre o controle do sistema nervoso autônomo sobre o sistema cardiovascular. OBJETIVO: O objetivo deste estudo foi testar a hipótese de associação entre a recuperação da freqüência cardíaca após teste de esforço em esteira ergométrica e a variabilidade da freqüência cardíaca. MÉTODOS: Foram estudamos 485 indivíduos sem evidência de cardiopatia com média de idade de 42± 12,1 (faixa etária de 15 a 82 anos, 281 (57.9% dos quais do sexo feminino, submetidos a um teste de esforço em esteira ergométrica e avaliação da VFC nos domínios do tempo (SDNN, SDANN, SDNNi, rMSSD e pNN50 e da freqüência (LF, HF, VLF e razão LF/HF durante monitoramento eletrocardiográfico ambulatorial de 24 horas. RESULTADOS: A recuperação da freqüência cardíaca foi de 30 ± 12 batimentos no 1º minuto e 52± 13 batimentos no 2º minuto após o exercício. Os indivíduos mais jovens de recuperaram mais rápido do 2º ao 5º minuto após o exercício (r = 0,19-0,35, P BACKGROUND: Heart rate recovery after treadmill electrocardiographic exercise stress test is modulated by the autonomic nervous system. Analysis of heart rate variability can provide useful information about autonomic control of the cardiovascular system. OBJECTIVE: The aim of the study was to test the hypothesis of association between heart recovery after treadmill electrocardiographic exercise test and heart rate variability. METHODS: We studied 485 healthy individuals aged 42± 12.1 (range 15-82 years, 281(57.9% women, submitted to treadmill electrocardiographic exercise stress tests and heart rate variability evaluations over time (SDNN, SDANN, SDNNi, rMSSD, pNN50 and frequency (LF, HF, VLF, LF/HF ratio domains in 24-hour ambulatory electrocardiographic monitoring. RESULTS: Heart rate recovery was 30± 12 beats in the 1st minute and 52± 13 beats in the 2nd minute after exercise. Younger individuals recovered faster from the 2nd to the 5th minute after exercise (r= 0.19-0.35, P< 0.05. Recovery was faster in women than in men (4± 1.1 beats lower in the 1st minute, p<0.001; 5.7± 1.2 beats lower in the 2nd minute, p<0.01; 4.1± 1.1 beats lower in the 3rd minute, p<0.001. There was no significant correlation between heart rate recovery and heart rate variability in 1st and 2nd minutes after exercise. SDNN, SDANN, SDNNi, rMSSD, and pNN50 indices demonstrated a significant correlation with heart rate recovery only at the 3rd and 4th minutes. CONCLUSION: The hypothesis of association between heart rate recovery and 24-hour heart rate variability in the first two minutes after exercise was not substantiated in this study. Heart rate recovery after exercise was associated with age and gender.

  4. The Relationship Between Daytime, Nighttime and 24-Hour Heart Rate with Urinary Albumin and Protein Excretion in Patients with Newly Diagnosed Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Bar?? AF?AR

    2012-05-01

    Full Text Available OBJECTIVE: Autonomic nervous system dysfunction (ASD has been widely observed in patients with type 2 diabetes. 24-hour ambulatory blood pressure (ABP and heart rate measurements have been found to associate with ASD in patient with Type 2 diabetes. Since albumin excretion is also related with ASD in type 2 diabetes; in the current study, the relationships between daytime, nighttime and 24- hour heart rates with 24 hour urinary albumin excretion (UAE and 24-hour urinary protein excretion (UPE were analyzed in patients with newly diagnosed type 2 diabetes. MATERIAL and METHODS: All patients underwent following procedures: history taking, physical examination, BP measurement, 12 lead electrocardiographic evaluations, routine urine analysis, biochemical analysis, 24-hour urine collection to measure UAE, UPE and creatinine clearance. 24-hour ABP and heart rate monitoring were performed for all patients. RESULTS: In total 80 patients with newly diagnosed type 2 diabetes were included. Stepwise linear regression revealed that logarithmically converted 24-hour UAE were independently related with 24- hour ambulatory SBP, (P:0.001 and heart rate (night (P<0.0001. Stepwise linear regression revealed that logarithmically converted 24-hour UPE were independently related with age (P:0.032, with averaged fasting blood glucose (P:0.023, with 24-hour ambulatory SBP, (P:0.002 and with heart rate (night (P:0.001. CONCLUSION: Nighttime heart rate, but not daytime and 24-hour heart rate was related with both 24-hour UAE and UPE in patients with Type 2 diabetes.

  5. Diagnostic performance of dual-source CT coronary angiography with and without heart rate control: Systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Aim: To investigate the diagnostic accuracy of dual-source computed tomography (DSCT) coronary angiography with and without the application of a ?-blocker. Materials and methods: An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize diagnostic test data. Results: The pooled sensitivity at the patient level was 0.98 [95% confidence intervals (CI): 0.97–0.99], and specificity 0.88 (95% CI: 0.84–0.91). The results showed that without heart rate control, the sensitivity and specificity at the patient level did not decrease (p = 0.27 and 0.56, respectively). At the artery level, no significant differences in sensitivity and specificity for studies with and without heart rate control were detected (p = 0.04 and 0.05, respectively). At the segment level, the specificity decreased without heart rate control (p = 0.03), whereas the sensitivity was not influenced (p = 0.63). The median radiation exposure was 2.6 mSv, with 1.6 mSv and 8 mSv for heart rate-controlled studies and uncontrolled studies, respectively. Conclusions: DSCT coronary angiography without heart rate control has a similar excellent diagnostic performance at the patient level as that of heart rate control groups. However, controlling for heart rate to decrease radiation and to provide effective information for selecting the therapeutic strategy and risk stratification is recommended

  6. Heart rate variability in normal and pathological sleep

    Directory of Open Access Journals (Sweden)

    EleonoraTobaldini

    2013-10-01

    Full Text Available Sleep is a physiological process involving different biological systems, from molecular to organ level; its integrity is essential for maintaining health and homeostasis in human beings. Although in the past sleep has been considered a state of quiet, experimental and clinical evidences suggest a noteworthy activation of different biological systems during sleep. A key role is played by the autonomic nervous system (ANS, whose modulation regulates cardiovascular functions during sleep onset and different sleep stages. Therefore, an interest on the evaluation of autonomic cardiovascular control in health and disease is growing by means of linear and non linear heart rate variability (HRV analyses. The application of classical tools for ANS analysis, such as HRV during physiological sleep, showed that the rapid eye movement (REM stage is characterized by a likely sympathetic predominance associated with a vagal withdrawal, while the opposite trend is observed during non-REM sleep. More recently, the use of non linear tools, such as entropy-derived indices, have provided new insight on the cardiac autonomic regulation, revealing for instance changes in the cardiovascular complexity during REM sleep, supporting the hypothesis of a reduced capability of the cardiovascular system to deal with stress challenges. Interestingly, different HRV tools have been applied to characterize autonomic cardiac control in different pathological conditions, from neurological sleep disorders to sleep disordered breathing (SDB. In summary, linear and non linear analysis of HRV are reliable approaches to assess changes of autonomic cardiac modulation during sleep both in health and diseases. The use of these tools could provide important information of clinical and prognostic relevance.

  7. Evaluation of heart rate changes: electrocardiographic versus photoplethysmographic methods

    Science.gov (United States)

    Low, P. A.; Opfer-Gehrking, T. L.; Zimmerman, I. R.; O'Brien, P. C.

    1997-01-01

    The heart rate (HR) variation to forced deep breathing (HRDB) and to the Valsalva maneuver (Valsalva ratio; VR) are the two most widely used tests of cardiovagal function in human subjects. The HR is derived from a continuously running electrocardiographic (ECG) recording. Recently, HR derived from the arterial waveform became available on the Finapres device (FinapHR), but its ability to detect rapid changes in HR remains uncertain. We therefore evaluated HRDB and VR derived from FinapHR using ECG-derived HR (ECGHR) recordings as the standard. We also compared the averaged HR on Finapres (Finapav) with beat-to-beat Finapres (FinapBB) values. Studies were undertaken in 12 subjects with large HR variations: age, 34.5 +/- 9.3 (SD) years; six males and six females. FinapBB values were superimposable upon ECGHR for both HRDB and VR. In contrast, Finapav failed to follow ECGHR for HRDB and followed HRECG with a lag for the VR. To evaluate statistically how closely FinapHR approximated ECGHR, we undertook regression analysis, using mean values for each subject. To compare the two methods, we evaluated the significance of the difference between test and standard values. For HRDB, FinapBB reproducibly recorded HR (R2 = 0.998), and was significantly (p = 0.001) better than Finapav (R2 = 0.616; p < 0.001). For VR, HRBB generated a VR that was not significantly different from the correct values, while HRav generated a value that was slightly but consistently lower than the correct values (p < 0.001). We conclude that FinapHR reliably records HR variations in the beat-to-beat mode for cardiovascular HR tests.

  8. Cross-country skiing and postexercise heart-rate recovery.

    Science.gov (United States)

    Mourot, Laurent; Fabre, Nicolas; Andersson, Erik; Willis, Sarah; Buchheit, Martin; Holmberg, Hans-Christer

    2015-01-01

    Postexercise heart-rate (HR) recovery (HRR) indices have been associated with running and cycling endurance-exercise performance. The current study was designed (1) to test whether such a relationship also exists in the case of cross-country skiing (XCS) and (2) to determine whether the magnitude of any such relationship is related to the intensity of exercise before obtaining HRR indices. Ten elite male cross-country skiers (mean ± SD; 28.2 ± 5.4 y, 181 ± 8 cm, 77.9 ± 9.4 kg, 69.5 ± 4.3 mL · min-1 · kg-1 maximal oxygen uptake [VO2max]) performed 2 sessions of roller-skiing on a treadmill: a 2 × 3-km time trial and the same 6-km at an imposed submaximal speed followed by a final 800-m time trial. VO2 and HR were monitored continuously, while HRR and blood lactate (BLa) were assessed during 2 min immediately after each 6-km and the 800-m time trial. The 6-km time-trial time was largely negatively correlated with VO2max and BLa. On the contrary, there was no clear correlation between the 800-m time-trial time and VO2, HR, or BLa. In addition, in no case was any clear correlation between any of the HRR indices and performance time or VO2max observed. These findings confirm that XCS performance is largely correlated with VO2max and the ability to tolerate high levels of BLa; however, postexercise HRR showed no clear association with performance. The homogeneity of the group of athletes involved and the contribution of the arms and upper body to the exercise preceding determination of HRR may explain this absence of a relationship. PMID:24806737

  9. Heart rate variability analysis in sheep affected by transmissible spongiform encephalopathies

    Directory of Open Access Journals (Sweden)

    Konold Timm

    2011-12-01

    Full Text Available Abstract Background The function of the autonomic nervous system can be assessed by determining heart rate variability (HRV, which is impaired in some brainstem diseases in humans. Transmissible spongiform encephalopathies (TSEs in sheep are diseases characterised by accumulation of disease-associated prion protein in the brainstem, including nuclei of the parasympathetic nervous system. This study was undertaken to assess whether analysis of HRV can be used as an aid in the diagnosis of TSEs in clinically affected, naturally or experimentally infected sheep. Findings When HRV indices were compared between 41 clinical TSE cases (18 sheep infected with scrapie and 23 sheep infected with bovine spongiform encephalopathy, 11 control sheep and six sheep reported as scrapie suspects or dosed with BSE brain homogenate, which were not confirmed as TSE cases by postmortem tests, no significant differences were found between the groups. Median heart rate was significantly different but only when sheep were grouped by gender: it was higher in female TSE cases than in control sheep and higher in female than castrated male ovine classical BSE cases. Conclusions HRV analysis was not useful as a diagnostic aid for TSEs of sheep.

  10. Peculiarities of indexes of autonomic regulation of blood circulation and heart rate variability in perimenopausal women

    Directory of Open Access Journals (Sweden)

    Neufeld I.W.

    Results: We have not revealed statistically significant differences in the most of indexes of autonomic regulation of blood circulation (except heart rate between the women groups with conserved menstrual cycle and in menopause. The majority of heart rate variability indexes correlated with the term of natural menopause (correlation coefficient r took values from 0.17 to 0.24. Remoteness of surgical menopause beginning correlated only with index S of synchronization between 0.1 Hz oscillations (r=-0.41, ?=0.039. Statistically (not clinically significant correlations were revealed between several indexes of autonomic regulation and sex hormone levels. Conclusion: We have not revealed clinically significant correlations between the indexes of cardiovascular system autonomic regulation and characteristics of menopausal status in women (sex hormone levels, hot flushes, and Kupperman index. However, we have shown statistically (not clinically significant correlations between several indexes of autonomic regulation and remoteness of menopause beginning (SDNN, CV, RMSSD, PNN50, power of low and high frequency bands correlated with natural menopause while index S correlated with surgical menopause and sex hormone levels.

  11. THE RELATIONSHIP BETWEEN SERUM LIPID FRACTIONS AND HEART RATE VARIABILITY IN DIABETIC PATIENTS WITH STATIN THERAPY

    Directory of Open Access Journals (Sweden)

    Anamaria Raluca Badea

    2014-09-01

    Full Text Available Background and aims. The aim of this study is to identify and highlight the relationship between serum lipid fractions and heart rate variability in diabetic patients receiving statin therapy.Patients and methods. The study was performed in a group of 87 type 2 diabetic patients on statin associated therapy. All patients were on Holter ECG 24 hours monitored with three channel monitor (Labtech ECG Holter monitor, and data were analyzed on a commercially available software (Cardiospy PC SW/EV 5.02.06.02. Concentrations of biochemical parameters were determined using specific enzymatic assays on an autoanalyzer Olympus AU 680. In the studied patients, we analyzed Holter/24 hours monitoring reports with respect to heart rate variability indexes, arrhythmic events and myocardial ischemia.Results. It was noticed that the mean values of serum TG were slightly elevated, TC levels were close to the limits specified by the guidelines for diabetic patients and for patients with cardiovascular diseases, with no significant differences between males and females. After analyzing the HRV in both time and frequency domains, we found no strong correlations between any of the HRV indexes and any of the lipid fractions.Conclusions. The results suggest that statin therapy may reduce the autonomic impairment secondary to dyslipidemia.

  12. Do physiological and pathological stresses produce different changes in heart rate variability?

    Directory of Open Access Journals (Sweden)

    GeoffreyGreen

    2013-07-01

    Full Text Available Although physiological (e.g. exercise and pathological (e.g. infection stress affecting the cardiovascular system have both been documented to be associated with a reduction in overall heart rate variability (HRV, it remains unclear if loss of HRV is ubiquitously similar across different domains of variability analysis or if distinct patterns of altered HRV exist depending on the stressor. Using Continuous Individualized Multiorgan Variability Analysis (CIMVATM software, heart rate (HR and four selected measures of variability were measured over time (windowed analysis from two datasets, a set (n=13 of patients who developed systemic infection (i.e. sepsis after bone marrow transplant, and a matched set of healthy subjects undergoing physical exercise under controlled conditions. HR and the four HRV measures showed similar trends in both sepsis and exercise. The comparison through Wilcoxon sign-rank test of the levels of variability at baseline and during the stress (i.e. exercise or after days of sepsis development showed similar changes, except for LF/HF, ratio of power at low and high frequencies (associated with sympathovagal modulation, which was affected by exercise but did not show any change during sepsis. Furthermore, HRV measures during sepsis showed a lower level of correlation with each other, as compared to HRV during exercise. In conclusion, this exploratory study highlights similar responses during both exercise and infection, with differences in terms of correlation and inter-subject fluctuations, whose physiologic significance merits further investigation.

  13. Heart rate variability during carbachol-induced REM sleep and cataplexy.

    Science.gov (United States)

    Torterolo, Pablo; Castro-Zaballa, Santiago; Cavelli, Matías; Velasquez, Noelia; Brando, Victoria; Falconi, Atilio; Chase, Michael H; Migliaro, Eduardo R

    2015-09-15

    The nucleus pontis oralis (NPO) exerts an executive control over REM sleep. Cholinergic input to the NPO is critical for REM sleep generation. In the cat, a single microinjection of carbachol (a cholinergic agonist) into the NPO produces either REM sleep (REMc) or wakefulness with muscle atonia (cataplexy, CA). In order to study the central control of the heart rate variability (HRV) during sleep, we conducted polysomnographic and electrocardiogram recordings from chronically prepared cats during REMc, CA as well as during sleep and wakefulness. Subsequently, we performed statistical and spectral analyses of the HRV. The heart rate was greater during CA compared to REMc, NREM or REM sleep. Spectral analysis revealed that the low frequency band (LF) power was significantly higher during REM sleep in comparison to REMc and CA. Furthermore, we found that during CA there was a decrease in coupling between the RR intervals plot (tachogram) and respiratory activity. In contrast, compared to natural behavioral states, during REMc and CA there were no significant differences in the HRV based upon the standard deviation of normal RR intervals (SDNN) and the mean squared difference of successive intervals (rMSSD). In conclusion, there were differences in the HRV during naturally-occurring REM sleep compared to REMc. In addition, in spite of the same muscle atonia, the HRV was different during REMc and CA. Therefore, the neuronal network that controls the HRV during REM sleep can be dissociated from the one that generates the muscle atonia during this state. PMID:25997581

  14. Heart Rate Variability in Overweight Health Care Students: Correlation with Visceral Fat

    Science.gov (United States)

    Krishna, Bandi Hari; N, Mallikarjuna Reddy

    2015-01-01

    Background and Objectives: Increased sympathetic activity, decreased parasympathetic activity and sympathovagal imbalance (SVI) has been reported in obese individuals. However, the SVI and its association with visceral fat in overweight health care students have not been explored. Therefore, in the present study, we have assessed heart rate variability (HRV) and its association with visceral fat in overweight health care students. Materials and Methods: Frequency domain parameters of HRV, body fat distribution and baseline anthropometric parameters were recorded in the control (n=40) and overweight (n=40) individuals. Further, the association of visceral fat with HRV was analysed. Results: There was no significant difference in age and height of overweight group and control group (p = 0.732). The baseline heart rate and blood pressure (p<0.001) were higher in the overweight group. Total body fat, subcutaneous fat and visceral fat were higher in the overweight group (p<0.001). Among frequency domain parameter of HRV, LFnu and LF: HF were more in the overweight group (p<0.001). Further, HFnu was less in the overweight group (p<0.001). Conclusion: Sympathovagal imbalance due to increased sympathetic activity and its association with visceral fat was observed in overweight individuals. PMID:25737980

  15. The effects of auditory stimulation with music on heart rate variability in healthy women

    Scientific Electronic Library Online (English)

    Adriano L., Roque; Vitor E., Valenti; Heraldo L., Guida; Monica F., Campos; Andre, Knap; Luiz Carlos M., Vanderlei; Lucas L., Ferreira; Celso, Ferreira; Luiz Carlos, de Abreu.

    2013-07-01

    Full Text Available OBJECTIVES: There are no data in the literature with regard to the acute effects of different styles of music on the geometric indices of heart rate variability. In this study, we evaluated the acute effects of relaxant baroque and excitatory heavy metal music on the geometric indices of [...] heart rate variability in women. METHODS: We conducted this study in 21 healthy women ranging in age from 18 to 35 years. We excluded persons with previous experience with musical instruments and persons who had an affinity for the song styles. We evaluated two groups: Group 1 (n?=?21), who were exposed to relaxant classical baroque musical and excitatory heavy metal auditory stimulation; and Group 2 (n?=?19), who were exposed to both styles of music and white noise auditory stimulation. Using earphones, the volunteers were exposed to baroque or heavy metal music for five minutes. After the first music exposure to baroque or heavy metal music, they remained at rest for five minutes; subsequently, they were re-exposed to the opposite music (70-80 dB). A different group of women were exposed to the same music styles plus white noise auditory stimulation (90 dB). The sequence of the songs was randomized for each individual. We analyzed the following indices: triangular index, triangular interpolation of RR intervals and Poincaré plot (standard deviation of instantaneous beat-by-beat variability, standard deviation of the long-term RR interval, standard deviation of instantaneous beat-by-beat variability and standard deviation of the long-term RR interval ratio), low frequency, high frequency, low frequency/high frequency ratio, standard deviation of all the normal RR intervals, root-mean square of differences between the adjacent normal RR intervals and the percentage of adjacent RR intervals with a difference of duration greater than 50 ms. Heart rate variability was recorded at rest for 10 minutes. RESULTS: The triangular index and the standard deviation of the long-term RR interval indices were reduced during exposure to both music styles in the first group and tended to decrease in the second group whereas the white noise exposure decreased the high frequency index. We observed no changes regarding the triangular interpolation of RR intervals, standard deviation of instantaneous beat-by-beat variability and standard deviation of instantaneous beat-by-beat variability/standard deviation in the long-term RR interval ratio. CONCLUSION: We suggest that relaxant baroque and excitatory heavy metal music slightly decrease global heart rate variability because of the equivalent sound level.

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

    Directory of Open Access Journals (Sweden)

    Mona Rayan

    2011-08-01

    Full Text Available Objective: To prospectively assess the safety and efficacy of ivabradine in patients with idiopathic dilated cardiomyopathy.Methods: 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.Results: 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. Conclusion: 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.

  17. Attenuated heart rate response in REM sleep behavior disorder and Parkinson's disease

    DEFF Research Database (Denmark)

    Sorensen, Gertrud Laura; Kempfner, Jacob

    2012-01-01

    The objective of this study was to determine whether patients with Parkinson's disease with and without rapid-eye-movement sleep behavior disorder and patients with idiopathic rapid-eye-movement sleep behavior disorder have an attenuated heart rate response to arousals or to leg movements during sleep compared with healthy controls. Fourteen and 16 Parkinson's patients with and without rapid-eye-movement sleep behavior disorder, respectively, 11 idiopathic rapid-eye-movement sleep behavior disorder patients, and 17 control subjects underwent 1 night of polysomnography. The heart rate response associated with arousal or leg movement from all sleep stages was analyzed from 10 heartbeats before the onset of the sleep event to 15 heartbeats following onset of the sleep event. The heart rate reponse to arousals was significantly lower in both parkinsonian groups compared with the control group and the idiopathic rapid-eye-movement sleep behavior disorder group. The heart rate response to leg movement was significantly lower in both Parkinson's groups and in the idiopathic rapid-eye-movement sleep behavior disorder group compared with the control group. The heart rate response for the idiopathic rapid-eye-movement sleep behavior disorder group was intermediate with respect to the control and the parkinsonian groups. The attenuated heart rate response may be a manifestation of the autonomic deficits experienced in Parkinson's disease. The idiopathic rapid-eye-movement sleep behavior disorder patients not only exhibited impaired motor symptoms but also incipient autonomic dysfunction, as revealed by the attenuated heart rate response.

  18. Sternal Pulse Rate Variability Compared with Heart Rate Variability on Healthy Subjects

    DEFF Research Database (Denmark)

    Chreiteh, Shadi; Belhage, Bo

    2014-01-01

    The heart rate variability (HRV) is a commonly used method to quantify the sympathetic and the parasympathetic modulation of the heart rate. HRV is mainly conducted on electrocardiograms (ECG). However, the use of photoplethysmography (PPG) as a marker of the autonomic tone is emerging. In this study we investigated the feasibility of deriving pulse rate variability (PRV) using PPG signals recorded by a reflectance PPG sensor attached to the chest bone (sternum) and comparing it to HRV. The recordings were conducted on 9 healthy subjects being in a relaxed supine position and under forced respiration, where the subjects were asked to breathe following a visual scale with a rate of 27 breaths/min. HRV parameters such as the mean intervals (meanNN), the standard deviation of intervals (SDNN), the root mean square of difference of successive intervals (RMSSD), and the proportion of intervals differing more than 50 ms (pNN50) were calculated from the R peak-to-R peak (R-R) and pulse-to-pulse (P-P) intervals. In the frequency domain the low and high frequency ratio of the power spectral density (LF/HF) was also computed. The Pearson correlation coefficient showed significant correlation for all the parameters (r > 0:95 with p < 0:001) and the Bland-Altmann analysis showed close agreement between the two methods for all the parameters during resting and forced respiration condition. Thus, PRV analysis using sternal PPG can be an alternative to HRV analysis on healthy subjects at rest.

  19. Sternal pulse rate variability compared with heart rate variability on healthy subjects

    DEFF Research Database (Denmark)

    Chreiteh, Shadi Samir; Belhage, Bo

    2014-01-01

    The heart rate variability (HRV) is a commonly used method to quantify the sympathetic and the parasympathetic modulation of the heart rate. HRV is mainly conducted on electrocardiograms (ECG). However, the use of photo-plethysmography (PPG) as a marker of the autonomic tone is emerging. In this study we investigated the feasibility of deriving pulse rate variability (PRV) using PPG signals recorded by a reflectance PPG sensor attached to the chest bone (sternum) and comparing it to HRV. The recordings were conducted on 9 healthy subjects being in a relaxed supine position and under forced respiration, where the subjects were asked to breathe following a visual scale with a rate of 27 breaths/min. HRV parameters such as the mean intervals (meanNN), the standard deviation of intervals (SDNN), the root mean square of difference of successive intervals (RMSSD), and the proportion of intervals differing more than 50 ms (pNN50) were calculated from the R peak-to-R peak (R-R) and pulse-to-pulse (P-P) intervals. In the frequency domain the low and high frequency ratio of the power spectral density (LF/HF) was also computed. The Pearson correlation coefficient showed significant correlation for all the parameters (r > 0.95 with p < 0.001) and the Bland-Altmann analysis showed close agreement between the two methods for all the parameters during resting and forced respiration condition. Thus, PRV analysis using sternal PPG can be an alternative to HRV analysis on healthy subjects at.

  20. Atrial fibrillation detection by heart rate variability in Poincare plot

    Directory of Open Access Journals (Sweden)

    Jeon Moongu

    2009-12-01

    Full Text Available Abstract Background Atrial fibrillation (AFib is one of the prominent causes of stroke, and its risk increases with age. We need to detect AFib correctly as early as possible to avoid medical disaster because it is likely to proceed into a more serious form in short time. If we can make a portable AFib monitoring system, it will be helpful to many old people because we cannot predict when a patient will have a spasm of AFib. Methods We analyzed heart beat variability from inter-beat intervals obtained by a wavelet-based detector. We made a Poincare plot using the inter-beat intervals. By analyzing the plot, we extracted three feature measures characterizing AFib and non-AFib: the number of clusters, mean stepping increment of inter-beat intervals, and dispersion of the points around a diagonal line in the plot. We divided distribution of the number of clusters into two and calculated mean value of the lower part by k-means clustering method. We classified data whose number of clusters is more than one and less than this mean value as non-AFib data. In the other case, we tried to discriminate AFib from non-AFib using support vector machine with the other feature measures: the mean stepping increment and dispersion of the points in the Poincare plot. Results We found that Poincare plot from non-AFib data showed some pattern, while the plot from AFib data showed irregularly irregular shape. In case of non-AFib data, the definite pattern in the plot manifested itself with some limited number of clusters or closely packed one cluster. In case of AFib data, the number of clusters in the plot was one or too many. We evaluated the accuracy using leave-one-out cross-validation. Mean sensitivity and mean specificity were 91.4% and 92.9% respectively. Conclusions Because pulse beats of ventricles are less likely to be influenced by baseline wandering and noise, we used the inter-beat intervals to diagnose AFib. We visually displayed regularity of the inter-beat intervals by way of Poincare plot. We tried to design an automated algorithm which did not require any human intervention and any specific threshold, and could be installed in a portable AFib monitoring system.

  1. Heart

    International Nuclear Information System (INIS)

    Ultrasonic anatomy of the heart and mediastinum provides a readily understandable dynamic assessment of one of the body's most important organs. Real-time ultrasound equipment, particularly sector scan devices, gives the clinician accurate and often conclusive evidence for the identification of a wide variety of medical disorders. In many cases, plain film radiography is necessary for either directing the ultrasound examination or evaluating structures beyond the reach of the beam, such as the pulmonary vessels and lung parenchyma. For many, if not most, structural abnormalities of the heart the ultrasound is the next logical diagnostic tool after x-ray film for providing useful information. Occasionally CT scanning may be required to clarify a structure's relationship to the mediastinum, to verify some aspects of aortic dissection, and to secure the diagnosis of a solid tumor suspected to be a lipoma. An awareness of the rewards of coordinating and correlating the various diagnostic approaches should be evident from the examples shown in this chapter

  2. Heart rate changes during the Valsalva maneuver in patients with isolated aortic insufficiency

    Scientific Electronic Library Online (English)

    A.E., Navarro; D.F., Dávila; A., Torres; G., Bellabarba; J.H., Donis; J., Casado.

    1997-09-01

    Full Text Available To determine the possible relationship between left ventricular dilatation and heart rate changes provoked by the Valsalva maneuver (Valsalva ratio), we studied 9 patients with isolated chronic aortic insufficiency. Left ventricular systolic function was assessed by two-dimensional echocardiography [...] and cardiac catheterization. All patients were asymptomatic (functional class I of the New York Heart Association). The left ventricular internal diameters and volumes were significantly increased in all patients. The asymptomatic patients had either normal or slightly depressed ejection fraction (EF>0.40). The Valsalva ratio of these asymptomatic patients showed no significant correlation with the left ventricular volumes or with the left ventricular ejection fraction. In other words, parasympathetic heart rate control, as expressed by the Valsalva ratio, was normal in the asymptomatic patients with left ventricular dilatation and preserved left ventricular ejection fraction. Therefore, left ventricular dilatation may not be the major mechanism responsible for the abnormal parasympathetic heart rate control of patients with acquired heart disease

  3. Heart rate changes during the Valsalva maneuver in patients with isolated aortic insufficiency

    Directory of Open Access Journals (Sweden)

    Navarro A.E.

    1997-01-01

    Full Text Available To determine the possible relationship between left ventricular dilatation and heart rate changes provoked by the Valsalva maneuver (Valsalva ratio, we studied 9 patients with isolated chronic aortic insufficiency. Left ventricular systolic function was assessed by two-dimensional echocardiography and cardiac catheterization. All patients were asymptomatic (functional class I of the New York Heart Association. The left ventricular internal diameters and volumes were significantly increased in all patients. The asymptomatic patients had either normal or slightly depressed ejection fraction (EF>0.40. The Valsalva ratio of these asymptomatic patients showed no significant correlation with the left ventricular volumes or with the left ventricular ejection fraction. In other words, parasympathetic heart rate control, as expressed by the Valsalva ratio, was normal in the asymptomatic patients with left ventricular dilatation and preserved left ventricular ejection fraction. Therefore, left ventricular dilatation may not be the major mechanism responsible for the abnormal parasympathetic heart rate control of patients with acquired heart disease

  4. Exercise-induced improvements in cardiorespiratory fitness and heart rate response to exercise are impaired in overweight/obese postmenopausal women

    Scientific Electronic Library Online (English)

    Emmanuel Gomes, Ciolac; Júlia Maria D' Andréa, Greve.

    Full Text Available OBJECTIVE: The purpose of this study was to compare the heart rate response to exercise and the exercise-induced improvements in muscle strength, cardiorespiratory fitness and heart rate response between normal-weight and overweight/obese postmenopausal women. METHODS: Sedentary women (n = 155) were [...] divided into normal-weight (n = 79; BMI 25 kg/m²; 58.3 + 8.6 years) groups, and have their 1-repetition maximum strength (adjusted for body mass), cardiorespiratory fitness and heart rate response to a graded exercise test compared before and after 12 months of a three times-per-week exercise-training program. RESULTS: Overweight/obese women displayed decreased upper and lower extremity muscle strengths, decreased cardiorespiratory fitness, and lower peak and reserve heart rates compared to normal-weight women. After follow-up, both groups improved their upper (32.9% and 41.5% in normal-weight and overweight/obese women, respectively) and lower extremity(49.5% and 47.8% in normal-weight and overweight/obese women, respectively) muscle strength. However, only normal-weight women improved their cardiorespiratory fitness (6.6%) and recovery heart rate (5 bpm). Resting, reserve and peak heart rates did not change in either group. CONCLUSIONS: Overweight/obese women displayed impaired heart rate response to exercise. Both groups improved muscle strength, but only normal-weight women improved cardiorespiratory fitness and heart rate response to exercise. These results suggest that exercise-induced improvements in cardiorespiratory fitness and heart rate response to exercise may be impaired in overweight/obese postmenopausal women.

  5. Exercise-induced improvements in cardiorespiratory fitness and heart rate response to exercise are impaired in overweight/obese postmenopausal women

    Directory of Open Access Journals (Sweden)

    Emmanuel Gomes Ciolac

    2011-01-01

    Full Text Available OBJECTIVE: The purpose of this study was to compare the heart rate response to exercise and the exercise-induced improvements in muscle strength, cardiorespiratory fitness and heart rate response between normal-weight and overweight/obese postmenopausal women. METHODS: Sedentary women (n = 155 were divided into normal-weight (n = 79; BMI 25 kg/m²; 58.3 + 8.6 years groups, and have their 1-repetition maximum strength (adjusted for body mass, cardiorespiratory fitness and heart rate response to a graded exercise test compared before and after 12 months of a three times-per-week exercise-training program. RESULTS: Overweight/obese women displayed decreased upper and lower extremity muscle strengths, decreased cardiorespiratory fitness, and lower peak and reserve heart rates compared to normal-weight women. After follow-up, both groups improved their upper (32.9% and 41.5% in normal-weight and overweight/obese women, respectively and lower extremity(49.5% and 47.8% in normal-weight and overweight/obese women, respectively muscle strength. However, only normal-weight women improved their cardiorespiratory fitness (6.6% and recovery heart rate (5 bpm. Resting, reserve and peak heart rates did not change in either group. CONCLUSIONS: Overweight/obese women displayed impaired heart rate response to exercise. Both groups improved muscle strength, but only normal-weight women improved cardiorespiratory fitness and heart rate response to exercise. These results suggest that exercise-induced improvements in cardiorespiratory fitness and heart rate response to exercise may be impaired in overweight/obese postmenopausal women.

  6. Real-time continuous estimation of respiratory frequency during sleep based on heart rate time series.

    Science.gov (United States)

    Yoshida, Yutaka; Yokoyama, Kiyoko; Ishii, Naohiro

    2007-01-01

    It is reported that frequency component (RSA) of approximately 0.25Hz of heart rate time series is corresponding to the respiratory frequency. In this paper, we proposed the continuous estimation method of respiratory frequency during sleep using the number of extreme points of heart rate time series in real time. Procedure for calculation of the method is very simple. Frequency of RSA was calculated using the proposed method from the heart rate time series during supine rest and during sleep. It is considered that the proposed method can be applied to respiratory monitoring system during sleep. PMID:18002039

  7. Determinants of short-period heart rate variability in the general population

    OpenAIRE

    Kuch, Bernhard; Hense, H. W.; Sinnreich, R.; Kark, J. D.; Eckardstein, A. Von; Sapoznikov, D.; Bolte, H. -d

    2001-01-01

    Decreased heart rate variability (HRV) is associated with a worse prognosis in a variety of diseases and disorders. We evaluated the determinants of short-period HRV in a random sample of 149 middle-aged men and 137 women from the general population. Spectral analysis was used to compute low-frequency (LF), high-frequency (HF) and total-frequency power. HRV showed a strong inverse association with age and heart rate in both sexes with a more pronounced effect of heart rate on HRV in women. Ag...

  8. Association of Body Composition and Aerobic Fitness on Heart Rate Variability and Recovery in Young-Adult Black Men

    OpenAIRE

    Esco, Michael R.; Herron, Robert L.; Carter, Stephen J.; Flatt, Andrew A.

    2013-01-01

    Background: The primary purpose of this investigation was to determine the differences in resting heart rate variability and heart rate recovery between norm-referenced aerobic fitness groupings, independent of body composition, in Black men. Additionally, we sought to clarify the independent relationships that heart rate variability and heart rate recovery displayed with maximal aerobic fitness and selected body composition measures. Methods: Body mass index, waist cir...

  9. Prospective and retrospective ECG-gating for CT coronary angiography perform similarly accurate at low heart rates

    International Nuclear Information System (INIS)

    Objective: To compare, in patients with suspicion of coronary artery disease (CAD) and low heart rates, image quality, diagnostic performance, and radiation dose values of prospectively and retrospectively electrocardiography (ECG)-gated dual-source computed tomography coronary angiography (CTCA) for the diagnosis of significant coronary stenoses. Materials and methods: Two-hundred consecutive patients with heart rates ?70 bpm were retrospectively enrolled; 100 patients undergoing prospectively ECG-gated CTCA (group 1) and 100 patients undergoing retrospectively-gated CTCA (group 2). Coronary artery segments were assessed for image quality and significant luminal diameter narrowing. Sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and accuracy of both CTCA groups were determined using conventional catheter angiography (CCA) as reference standard. Radiation dose values were calculated. Results: Both groups were comparable regarding gender, body weight, cardiovascular risk profile, severity of CAD, mean heart rate, heart rate variability, and Agatston score (all p > 0.05). There was no significant difference in the rate of non-assessable coronary segments between group 1 (1.6%, 24/1404) and group 2 (1.4%, 19/1385; p = 0.77); non-diagnostic image quality was significantly (p 0.05). Mean effective radiation dose of prospectively ECG-gated CTCA (2.2 ± 0.4 mSv) was significantly (p < 0.0001) smaller than that of retrospectively ECG-gated CTCA (8.1 ± 0.6 mSv). Conclusion: Prospectively ECG-gated CTCA yields similar image quality, performs as accurately as retrospectively ECG-gated CTCA in patients having heart rates ?70 bpm while being associated with a lower mean effective radiation dose.

  10. Temporary decrease in heart rate in Lyme carditis during treatment with antibiotics.

    OpenAIRE

    Dam, E. P.; Jonker, D. R.; Hoorntje, J. C.

    1996-01-01

    Lyme disease is a recognised cause of atrioventricular block. In most cases the conduction disturbances are reversed by treatment with antibiotics. A 44 year old man with third degree atrioventricular block in Lyme carditis had a temporary decrease in heart rate during resolution of the heart block two days after treatment with antibiotics was started.

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

    International Nuclear Information System (INIS)

    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

  12. Reproducibility and relation to mean heart rate of heart rate variability in normal subjects and in patients with congestive heart failure secondary to coronary artery disease.

    Science.gov (United States)

    Van Hoogenhuyze, D; Weinstein, N; Martin, G J; Weiss, J S; Schaad, J W; Sahyouni, X N; Fintel, D; Remme, W J; Singer, D H

    1991-12-15

    Before heart rate (HR) variability can be used for predictive purposes in the clinical setting, day-to-day variation and reproducibility need to be defined as do relations to mean HR. HR variability and mean HR were therefore determined in 2 successive 24-hour ambulatory electrocardiograms obtained from 33 normal subjects (age 34 +/- 7 years, group I), and 22 patients with coronary disease and stable congestive heart failure (CHF) (age 59 +/- 7 years, group II). Three measures were used: (1) SDANN (standard deviation of all mean 5-minute normal sinus RR intervals in successive 5-minute recording periods over 24 hours); (2) SD (the mean of the standard deviation of all normal sinus RR intervals in successive 5-minute recording periods over 24 hours); and (3) CV (coefficient of variation of the SD measure), a new measure that compensates for HR effects. Group mean HR was higher and HR variability lower in group II than in group I (80 +/- 10 vs 74 +/- 9 beats/min, p less than 0.04). Mean group values for HR and HR variability showed good correlations between days 1 and 2 (mean RR, r = 0.89, 0.97; SDANN, r = 0.87, 0.87; SD, r = 0.93, 0.97; CV, r = 0.95, 0.97 in groups I and II, respectively). In contrast, considerable individual day-to-day variation occurred (group I, 0 to 46%; group II, 0 to 51%). Low HR variability values were more consistent than high values. SDANN and SD correlated moderately with HR in both groups (r = 0.50 to 0.64). The CV measure minimizes HR effects on HR variability.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1746470

  13. ROC Analysis and a Realistic Model of Heart Rate Variability

    CERN Document Server

    Thurner, S; Teich, M C; Thurner, Stefan; Feurstein, Markus C.; Teich, Malvin C.

    1998-01-01

    We have carried out a pilot study on a standard collection of electrocardiograms from patients who suffer from congestive heart failure, and subjects without cardiac pathology, using receiver-operating-characteristic (ROC) analysis. The scale-dependent wavelet-coefficient standard deviation superior to two commonly used measures of cardiac dysfunction when the two classes of patients cannot be completely separated. A jittered integrate-and-fire model with a fractal Gaussian-noise kernel provides a realistic simulation of heartbeat sequences for both heart-failure patients and normal subjects.

  14. Premature Born Infant's Reaction to the Mother's Voice in Comparison to their Reaction to Music - Effect on Heart Rate and Heart Rate Variability

    OpenAIRE

    Djordjevic, Dragana

    2010-01-01

    OBJECTIVE: The aim of the study was to compare stress-reduction effects of the mother’s voice and lullaby music in preterm infants and to explore whether the mother’s well-being affects her ability to calm down her preterm baby. It was hypothesized that both acoustic stimulation interventions can calm down the baby, i.e. decrease heart rate and increase heart rate variability (HRV) in preterm infants. Further it was hypothesized that the mother’s voice would have greater effect than lul...

  15. Happiness and heart rate response: a case of fan services at japanese professional baseball games

    Directory of Open Access Journals (Sweden)

    Muneo Kitajima

    2011-03-01

    Full Text Available The aim of this study was to develop a method for predicting the psychological states of spectators watching professional baseball games at a stadium. This method includes a real time measurement of instantaneous heart rate (i.e., the inverse of the RR interval without preventing the subject from watching the game and a mathematical procedure used to predict moment by moment psychological states by correlating the degree of a psychological state with the strength of heart rate response, defined as the mean deviation of heart rate variability from a linear regression line from 5 sec before to 25 sec after an event during a baseball game. We recorded the instantaneous heart rates of 10 subjects (total of 27 cases while they watched Japanese professional baseball games at a stadium and had them subjectively rate the degree of their psychological states in an after-event interview. We identified three psychological states (happiness, excitement, and vigor whose strength can be predicted from the strength of heart rate response. Analysis of the measured data clarified that heart rate response had a significant correlation with the subjective rating of the intensity of happiness (r = 0.56, p < 0.0001, vigor (r = 0.55, p < 0.0001, and excitement (r = 0.49, p < 0.0001.

  16. 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.

  17. 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

  18. Spectral and Time-Domain Analyses of Heart-Rate Variability in Children with Severe Upper Airway Obstruction

    Directory of Open Access Journals (Sweden)

    Berna ?aylan

    2011-06-01

    Full Text Available Objective: Heart rate variability (HRV is a noninvasive index of neural activity of the heart. This study assessed the heart-rate variability response in children with severe upper airway obstruction. Material and Methods: A prospective trial was carried out in 15 children with severe adenoid and/or tonsil hypertrophy, compared to 15 age matched healthy children in order to attempt to relate such changes. Frequency domain measurements of the high and low frequency bands and the ratio low frequency/high frequency were derived from Holter electrocardiography recordings and computed by Fast Fourier analysis for five minute intervals. Time domain measurements were derived from 24 hour Holter recordings.Results: All spectral analysis of heart rate variability was altered in both preoperative and postoperative (three months after the operation recordings compared to the control group. In both groups, time domain indices were significantly lower compared to the control group. Mean R-R values were significantly reduced in pre and postoperative groups compared with control group, with the night time mean R-R values being significantly lower (p<0.05. These results indicate the increased frequency domain parameters in two groups. Conclusion: In this study, patients demonstrated altered volume loads and autonomic response. Further studies are needed to assess when such cardiac findings normalize upon relief of the upper airway obstruction.

  19. Investigating the effects of cognitive interventions on reducing pain intensity and modifying heart rate and oxygen saturation level

    Directory of Open Access Journals (Sweden)

    Shahriar Shahidi

    2011-10-01

    Full Text Available Introduction:In the present study, we investigated the efficacy of cognitive interventions in reducing reported pain intensity as well as modifying heart rate or oxygen saturation level in children with cancer during lumbar puncture or intrathecal injection. Moreover, we studied the relationship between the reported pain intensity and changes in heart rate and oxygen saturation level resulting from lumbar puncture or intrathecal injection.Material and Methods:This is a clinical trial using a pretest-posttest design with control group. 41 child-parent pairs were selected and randomly assigned to two groups. The children were visited twice; on first visit, both groups received routine care. On second visit, the experiment group received cognitive interventions and the second group received routine care. Data were collected using a demographic questionnaire, Oucher’s self-report pain intensity scale, and pulse oximeter. We used analysis of covariance and Pearson’s correlation to analyze the data.Results:Our findings indicate that the interventions efficiently reduce reported pain intensity, lower heart rate and increase blood oxygen saturation level during lumbar puncture or intrathecal injection. We also found a significant positive correlation between reported pain intensity and changes in heart rate, and a significant negative relationship between reported pain intensity and changes in oxygen saturation level. Conclusion:Cognitive interventions are efficient for reducing reported pain intensity, lowering heart rate and increasing oxygen saturation level during lumbar puncture or intrathecal injection. We recommend cognitive interventions to be used during this painful procedure to manage pain and minimize physiologic changes resulting from lumbar puncture.

  20. Facial electromyogram and heart-rate correlates of a paradoxical attitude change to antinuclear war information

    International Nuclear Information System (INIS)

    The effects of film images versus film descriptions of the effects of nuclear explosions (versus a no-film control) on corrugator muscle tension, heart rate, attitude and mood were investigated. The last 5 min. of the images were associated with more corrugator tension for that condition when compared to the last 5 min. of the description condition. The groups did not differ in heart rate but women in both groups showed an increase in heart rate whereas men in both groups showed a decrease in heart rate. Film groups did not differ in their significant increases in anxiety, hostility, and depression on the Multiple Adjective Affect Checklist. On the pretest there was no significant correlation between scores on Betts' Questionnaire Upon Mental Imagery and scores on Goldenring and Doctor's index of concern for nuclear war. The vivid-image film group showed a decrease in concern for nuclear war when compared to the descriptive film group and the no-film control

  1. Lactic acidosis, potassium, and the heart rate deflection point in professional road cyclists

    OpenAIRE

    De Lucia, A.; Hoyos, J; Santalla, A; Perez, M.; Carvajal, A; Chicharro, J

    2002-01-01

    Objective: To determine the influence of lactic acidosis, the Bohr effect, and exercise induced hyperkalaemia on the occurrence of the heart rate deflection point (HRDP) in elite (professional) cyclists.

  2. Effect of ultramarathon cycling on the heart rate in elite cyclists

    OpenAIRE

    Neumayr, G; Pfister, R.; Mitterbauer, G; Maurer, A.; Hoertnagl, H

    2004-01-01

    Objectives: To analyse the heart rate (HR) response and estimate the ultraendurance threshold—the optimum maintainable exercise intensity of ultraendurance cycling—in ultraendurance elite cyclists competing in the Race across the Alps.

  3. Development and validation of an improved smartphone heart rate acquisition system

    Science.gov (United States)

    Karapetyan, G.; Barseghyan, R.; Sarukhanyan, H.; Agaian, S.

    2015-03-01

    In this paper we propose a robust system for touchless heart rate (HR) acquisition on mobile devices. The application allows monitor heart rate signal during usual mobile device usage such as video watching, games playing, article reading etc. The system is based on algorithm of acquiring heart rate via recording of skin color variations with built-in cameras of mobile device. The signal is acquired from different ROIs of human face, which make it more clear and the amplification of the signal improve the robustness in low lightening conditions. The effectiveness and robustness of the developed system has been demonstrated under different distances from camera source and illumination conditions. The experiments have been done with different mobile devices HRs were collected from 10 subjects, ages 22 to 65, by using the 3 devices. Moreover, we compared the developed method with Food and Drug Administration (FDA) approved sensors and related commercial applications of remote heart rate measurements on mobile devices.

  4. Attenuated heart rate response is associated with hypocretin deficiency in patients with narcolepsy

    DEFF Research Database (Denmark)

    Sorensen, Gertrud Laura; Knudsen, Stine

    2013-01-01

    Several studies have suggested that hypocretin-1 may influence the cerebral control of the cardiovascular system. We analyzed whether hypocretin-1 deficiency in narcolepsy patients may result in a reduced heart rate response.

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

    International Nuclear Information System (INIS)

    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)

  6. Using complexity metrics with R-R intervals and BPM heart rate measures.

    Science.gov (United States)

    Wallot, Sebastian; Fusaroli, Riccardo; Tylén, Kristian; Jegindø, Else-Marie

    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 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 on variability of the data, different choices regarding the kind of measures can have a substantial impact on the results. In this article we compare linear and non-linear statistics on two prominent types of heart beat data, beat-to-beat intervals (R-R interval) and beats-per-min (BPM). As a proof-of-concept, we employ a simple rest-exercise-rest task and show that non-linear statistics-fractal (DFA) and recurrence (RQA) analyses-reveal information about heart beat activity above and beyond the simple level of heart rate. Non-linear statistics unveil sustained post-exercise effects on heart rate dynamics, but their power to do so critically depends on the type data that is employed: While R-R intervals are very susceptible to non-linear analyses, the success of non-linear methods for BPM data critically depends on their construction. Generally, "oversampled" BPM time-series can be recommended as they retain most of the information about non-linear aspects of heart beat dynamics. PMID:23964244

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

    DEFF Research Database (Denmark)

    Wallot, Sebastian; Fusaroli, Riccardo

    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 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 on variability of the data, different choices regarding the kind of measures can have a substantial impact on the results. In this article we compare linear and non-linear statistics on two prominent types of heart beat data, beat-to-beat intervals (R-R interval) and beats-per-minute (BPM). As a proof-of-concept, we employ a simple rest-exercise-rest task and show that non-linear statistics – fractal (DFA) and recurrence (RQA) analyses – reveal information about heart beat activity above and beyond the simple level of heart rate. Non-linear statistics unveil sustained post-exercise effects on heart rate dynamics, but their power to do so critically depends on the type data that is employed: While R-R intervals are very susceptible to nonlinear analyses, the success of nonlinear methods for BPM data critically depends on their construction. Generally, ‘oversampled’ BPM time-series can be recommended as they retain most of the information about nonlinear aspects of heart beat dynamics.

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

    Directory of Open Access Journals (Sweden)

    SebastianWallot

    2013-08-01

    Full Text Available 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 on variability of the data, different choices regarding the kind of measures can have a substantial impact on the results. In this article we compare linear and non-linear statistics on two prominent types of heart beat data, beat-to-beat intervals (R-R interval and beats-per-minute (BPM. As a proof-of-concept, we employ a simple rest-exercise-rest task and show that non-linear statistics – fractal (DFA and recurrence (RQA analyses – reveal information about heart beat activity above and beyond the simple level of heart rate. Non-linear statistics unveil sustained post-exercise effects on heart rate dynamics, but their power to do so critically depends on the type data that is employed: While R-R intervals are very susceptible to nonlinear analyses, the success of nonlinear methods for BPM data critically depends on their construction. Generally, ‘oversampled’ BPM time-series can be recommended as they retain most of the information about nonlinear aspects of heart beat dynamics.

  9. Chaotic Behavior of Heart Rate Signals during Chi and Kundalini Meditation

    OpenAIRE

    Atefeh Goshvarpour; Ateke Goshvarpour

    2012-01-01

    Nonlinear dynamics has been introduced to the analysis of biological data and increasingly recognized to be functionally relevant. The aim of this study is to quantify and compare the contribution of nonlinear and chaotic dynamics of human heart rate variability during two forms of meditation: (i) Chinese Chi (or Qigong) meditation and (ii) Kundalini Yoga meditation. For this purpose, Poincare plots, Lyapunov exponents and Hurst exponents of heart rate variability signals were analyzed. In th...

  10. Modifications to an optocardiographic method for measurement of heart rate in a range of invertebrate species

    OpenAIRE

    Aardt, W. J.; Vosloo, A.

    2011-01-01

    A non-invasive technique developed by Depledge & Andersen (1990) on a crab and a lamellibranchiate wasused in this study to measure heart rate activity in a millipede, centipede, spider, two scorpion species, two crabspecies, three insect species and the garden snail. A novel technique to confine smaller arthropods in an aluminiumfoil bag provided with a 7 mm by 7 mm opening allowed heart rate measurements to be done on spid~rs,insects, centipedes and scorpions without direct body contact...

  11. Nomenclature, categorization and usage of formulae to adjust QT interval for heart rate

    OpenAIRE

    Rabkin, Simon W.; Cheng, Xin Bo

    2015-01-01

    Assessment of the QT interval on a standard 12 lead electrocardiogram is of value in the recognition of a number of conditions. A critical part of its use is the adjustment for the effect of heart rate on QT interval. A systematic search was conducted to identify studies that proposed formulae to standardize the QT interval by heart rate. A nomenclature was developed for current and subsequent equations based on whether they are corrective (QTc) or predictive (QTp). QTc formulae attempt to se...

  12. New Cardiovascular Risk Factors; Resting Heart Rate, Hs-CRP, Fibrinogen and PMNL

    OpenAIRE

    Mehmet Aktu?lu; Abdülbaki Kumbasar; Hülya Çilingir; Mehmet Beliba?l?

    2012-01-01

    Aim: In this study we aimed to evaluate the possibility of a presence of an association between the high resting heart rate and micro inflammatory response and with the help of any found, clarify the recently identified negative cardiovascular prognosis in individuals with high resting heart rate from an etiological point of view. Material and Method: Study was conducted in September, 2009 with a total of 67 male cases consisting of 36 cases that are followed up at Haseki Egt. ve Ars. Hospita...

  13. Habitual physical activity and heart rate variability in 12-year old children

    OpenAIRE

    Wennman, Heini

    2012-01-01

    ABSTRACT Wennman, Heini 2012. Habitual physical activity and heart rate variability in 12-year old children. Department of Biology of Physical Activity, University of Jyväskylä, 92p. The study of heart rate variability (HRV) provides useful information about the function of the cardiac autonomic nervous system. The effects of many environmental factors on HRV are well known, but the associations between physical activity (PA) and HRV, especially in children, are less investigated. ...

  14. Total cavopulmonary and atriopulmonary connections are associated with reduced heart rate variability

    OpenAIRE

    Butera, G.; Bonnet, D.; Iserin, L.; Sidi, D.; Kachaner, J.; Villain, E.

    1999-01-01

    AIM—To determine whether cavopulmonary connections are associated with abnormalities of heart rate variability.?METHODS—Heart rate variability was studied by 24 hour Holter monitoring in 39 patients (mean (SD) age 12.2 (4.1) years) who underwent cavopulmonary connection operations (partial in 12, total in 13, and atriopulmonary in 14). Two control groups were used: 18 healthy children (11.1 (2.5) years) and 16 patients (11.7 (4.3) years) undergoing cardiovascular surgery for bi...

  15. Estimation system of cardiovascular circulatory system state based on 24h heart rate

    OpenAIRE

    Kyselova, Olga; Nastenko, Yevgen

    2013-01-01

    The goal of this research was to develop the methods and tools for the analysis of cardiovascular circulatory system states, early prediction of the probability of sudden cardiac arrest, as well as analysis of various cardiac arrhythmias based on the dynamics of the 24-hours heart rate. Using «k-means" method based on MacQueen algorithm, the automated classification of heart rate fragments was made. The most informative procedure was referring specific observation to the functional patter...

  16. Heart Rate Variability Responses of a Preterm Infant to Kangaroo Care

    OpenAIRE

    McCain, Gail C.; Susan M. Ludington-Hoe; Swinth, Joan Y.; Hadeed, Anthony J.

    2005-01-01

    A 35-week old preterm infant's behavior was fussy and restless in the open crib, but he calmed and fell asleep immediately on being placed skin-to-skin on his mother's chest. Heart rate variability (HRV), a noninvasive method to assess the autonomic nervous system's influence on heart rate, was increased with fussy behavior in the open crib and decreased with sleep during kangaroo care (KC). KC produced changes in behavior and HRV that are illustrative of decreasing stress.

  17. Effects of particulate air pollution on blood pressure and heart rate in subjects with cardiovascular disease: a multicenter approach.

    OpenAIRE

    Ibald-mulli, Angela; Timonen, Kirsi L.; Peters, Annette; Heinrich, Joachim; Wo?lke, Gabriele; Lanki, Timo; Buzorius, Gintautas; Kreyling, Wolfgang G.; Hartog, Jeroen; Hoek, Gerard; Ten Brink, Harry M.; Pekkanen, Juha

    2004-01-01

    Given the hypothesis that air pollution is associated with elevated blood pressure and heart rate, the effect of daily concentrations of air pollution on blood pressure and heart rate was assessed in 131 adults with coronary heart disease in Helsinki, Finland; Erfurt, Germany; and Amsterdam, the Netherlands. Blood pressure was measured by a digital monitor, and heart rate was calculated as beats per minute from an electrocardiogram recording with the patient in supine position. Particle conce...

  18. Blue 405 nm laser light mediates heart rate – investigations at the acupoint Neiguan (Pe.6) in Chinese adults

    OpenAIRE

    Gerhard Litscher; Zheng Xie; Lu Wang; Ingrid Gaischek

    2009-01-01

    Background: In previous studies, we showed that laser needle acupuncture with red and infrared light has specific effects on bio-signals of the brain and heart. Aims: In this publication we report the effect of blue laser light on heart rate and heart rate variability (HRV) before, during and after acupuncture at the acupoint Neiguan (Pe.6) in Chinese adults. These are the first data published concerning heart rate and HRV, obtained with blue laser acupuncture equipment. Patients and Methods:...

  19. Heart Rate Variability and its Correlation with Pulmonary Function Test of Smokers

    Science.gov (United States)

    Behera, Joshil Kumar; Sood, Sushma; Kumar, Naresh; Sharma, Kirti; Mishra, Reshmi; Roy, Prasanta Saha

    2013-01-01

    Context: Though many studies have been conducted on the effect of chronic smoking on pulmonary function test (PFT) and heart rate variability (HRV), no study has found a correlation between the pulmonary function test and heart rate variability parameters so far. Aim: The aim was to study if there was a correlation, if any, between PFT and HRV. Settings and Design: Thirty male subjects who were chronic smokers of at least 10 pack years and another 30 nonsmoking healthy males were included in the study and were matched for age, height, weight, and body surface area. Materials and Methods: PFT and HRV were performed on these subjects and a correlation was statistically derived. Statistical Analysis Used: Spearman?s correlation coefficient was used for the analysis of HRV and PFT. Multiple stepwise regression analysis was used subsequently. Results: HF and LF showed correlation coefficients of 0.378 and-0.383 with forced expiratory volume in the first second (FEV 1) and peak expiratory flow rate (PEFR), respectively. It was found that only FEV 1/FVC was having a statistically significant regression coefficient with HF the R-value was found to be 0.425 while with other parameters, it was not significant. Conclusion: We conclude that smoking affects all the parameters of PFT and HRV. Since there is a correlation between PFT parameters (PEFR and FEV1) and HRV parameter (LF and HF), this can help us in predicting cardiac morbidity in chronic smokers. So HRV should be included as a routine test along with PFT in chronic smokers for early diagnosis of cardiac involvement. PMID:23580921

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

    DEFF Research Database (Denmark)

    Andersen, Mads Peter; Xue, Joel Q

    2008-01-01

    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 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, flatness, and others), ToTe intervals and TpTe intervals, were practically independent of heart rate (R(2) = 0-0.08), making heart rate correction unnecessary for these parameters.

  1. Effect of Exercise Testing on Short-term Heart Rate Variability in Patients with Coronary Heart Disease

    DEFF Research Database (Denmark)

    Niu, Hui-Yan; Zhang, Dai-Fu

    2005-01-01

    Objective To study the effect of exercise testing on short term heart rate variability in patients with CHD.Methods In 12 patients with CHD and 12 age-and sex-matched healthy controls, short-term frequency domain analysis was performed at respective stage before, during and after ET.Results It showed that (1) No significant difference was detected in 5-minute frequency domain (LFnorm, HFnorm and LF/HF) of stationary supine position before exercise (P0.05) between CHD and controls. In CHD, there was no significant difference in 5-minute frequency spectral components of supine position between pre-exercise and post-exercise results (P0.05); (2) All of LFnorm, HFnorm and LF/HF were found to decrease gradually during ET and to reach the lowest levels in maximal ET and to increase during the recovery period in both CHD and controls (P0.05).Between the two groups, significant difference was shown in the second 5-minute frequency domain analysis (LFnorm, HFnorm and LF/HF) after ET(P0.05); (3) In the whole course of ET,the frequency domain analysis showed that LF and LFnorm were higher and HF,HFnorm were lower in CHD than those in controls.Conclusion It is concluded that (1) Sympathovagal nervous system remains balanced in patients with CHD in stationary supine position without myocardiac ischemia; (2) Vagal tone withdraws during the exercise time and increases during the recovery period; (3) The changes of HRV in patients with CHD present ischemia-induced reflective sympathetic activity predominance during the recovery period; (4) The autonomic nervous system in CHD is disordered during ET. This results suggest that ET is helpful in detecting the disorder of sympathovagal nervous system in patients with CHD.

  2. Building trust: Heart rate synchrony and arousal during joint action increased by public goods game.

    Science.gov (United States)

    Mitkidis, Panagiotis; McGraw, John J; Roepstorff, Andreas; Wallot, Sebastian

    2015-10-01

    The physiological processes underlying trust are subject of intense interest in the behavioral sciences. However, very little is known about how trust modulates the affective link between individuals. We show here that trust has an effect on heart rate arousal and synchrony, a result consistent with research on joint action and experimental economics. We engaged participants in a series of joint action tasks which, for one group of participants, was interleaved with a PGG, and measured their heart synchrony and arousal. We found that the introduction of the economic game shifted participants' attention to the dynamics of the interaction. This was followed by increased arousal and synchrony of heart rate profiles. Also, the degree of heart rate synchrony was predictive of participants' expectations regarding their partners in the economic game. We conclude that the above changes in physiology and behavior are shaped by the valuation of other people's social behavior, and ultimately indicate trust building process. PMID:26037635

  3. Sweet Conclusion

    Science.gov (United States)

    Shirley, Britt M.; Wooldridge, Barbara Ross; Camp, Kerri M.

    2012-01-01

    Jen Harrington is the owner and pastry chef of Sweet Conclusion, a bakery in Tampa, Florida. Most of Harrington's business comes from baking wedding cakes, but she has been attempting to attract customers to her retail bakery, where she sells cupcakes, pies, ice cream, and coffee. Nearly four years she opened Sweet Conclusion, the retail part of…

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

    International Nuclear Information System (INIS)

    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)

  5. The Tell-Tale Heart: heart rate fluctuations index objective and subjective events during a game of chess

    OpenAIRE

    MariaJulianaLeone; DiegoFFernandez Slezak

    2012-01-01

    During a decision-making process, the body changes. These somatic changes have been related to specific cognitive events and also have been postulated to assist decision-making indexing possible outcomes of different options. We used chess to analyze heart rate (HR) modulations on specific cognitive events. In a chess game, players have a limited time-budget to make about 40 moves (decisions) that can be objectively evaluated and retrospectively assigned to specific subjectively perceived eve...

  6. Modest weight loss in moderately overweight postmenopausal women improves heart rate variability

    DEFF Research Database (Denmark)

    Mouridsen, Mette Rauhe; Bendsen, Nathalie Tommerup

    2013-01-01

    Purpose: To evaluate the effects of weight loss on heart rate (HR) and heart rate variability (HRV) parameters in overweight postmenopausal women. Design and Methods: Forty-nine overweight postmenopausal women with an average body mass index of 28.8 1.9 kg/m2 underwent a 12-week dietary weight-loss programme. Accepted variables for characterization of HRV were analysed before and after the weight loss by 24-h ambulatory ECG monitoring; mean and standard deviation for the time between normal-to-normal complexes (MeanNN and SDNN, respectively), and the mean of standard deviations of normal-to-normal intervals for each 5-min period (SDNNindex). Baseline body fat mass (FM%) and changes in body composition was determined by dual X-ray absorptiometry. Before and after the weight-loss period, total abdominal fat, intra-abdominal fat (IAAT), and subcutaneous abdominal fat (SCAT) were measured by single-slice MRI at L3. Results: The weight loss of 3.9 2.0 kg was accompanied by an improvement of HRV. SDNN increasedby 9.2% (p ¼ 0.003) and SDNNindex increased by 11.4% (p ¼ 0.0003). MeanNN increased by 2.4%, reflecting a decrease in mean heart rate from 74.1 to 72.3 beats/min (p ¼ 0.033). Systolic blood pressure (SBP) decreased by 2.7%, total cholesterol by 5.1% and high-sensitivity C-reactive protein (hsCRP) by 15.8% (p ¼ 0.002). Improvements in SDNN and cholesterol were correlated with weight loss (r ¼ 0.329, p ¼ 0.024 and r ¼ 0.327, p ¼ 0.020, respectively) but changes in HR, SBP, and hsCRP were not. IAAT and the IAAT/SCAT-ratio were found to be negatively associated with HRV parameters but changes in body composition were not associated with changes in HRV. Conclusions: The observed improvement of HRV seems to be facilitated by weight loss. IAAT and the IAAT/SCAT ratio were found to be associated with low HRV.

  7. Assessment of skeletal muscle fatigue of road maintenance workers based on heart rate monitoring and myotonometry

    Directory of Open Access Journals (Sweden)

    Kalkis Henrijs

    2006-07-01

    Full Text Available Abstract Objective This research work is dedicated to occupational health problems caused by ergonomic risks. The research object was road building industry, where workers have to work very intensively, have long work hours, are working in forced/constrained work postures and overstrain during the work specific parts of their bodies. The aim of this study was to evaluate the work heaviness degree and to estimate the muscle fatigue of workers after one week work cycle. The study group consisted of 10 road construction and maintenance workers and 10 pavers aged between 20 and 60 years. Methods Physical load were analyzed by measuring heart rate (HR, work postures (OWAS and perceived exertion (RPE. Assessments of the muscles strain and functional state (tone were carried out using myotonometric (MYO measurements. The reliability of the statistical processing of heart rate monitoring and myotonometry data was determined using correlating analysis. Results This study showed that that road construction and repairing works should be considered as a hard work according to average metabolic energy consumption 8.1 ± 1.5 kcal/min; paving, in its turn, was a moderately hard work according to 7.2 ± 1.1 kcal/min. Several muscle tone levels were identified allowing subdivision of workers into three conditional categories basing on muscle tone and fatigue: I – absolute muscle relaxation and ability to relax; II – a state of equilibrium, when muscles are able to adapt to the work load and are partly able to relax; and III – muscle fatigue and increased tone. It was also found out that the increase of muscle tone and fatigue mainly depend on workers physical preparedness and length of service, and less – on their age. Conclusion We have concluded that a complex ergonomic analysis consisting of heart rate monitoring, assessment of compulsive working postures and myotonometry is appropriate to assess the work heaviness degree and can provide prognosis of occupational pathology or work-related musculoskeletal disorders for the workers under different workload conditions. These results can also be used when deciding on necessary rest time and its periodicity.

  8. Oxygen consumption, heart rate, rating of perceived exertion, and systolic blood pressure with water treadmill walking.

    Science.gov (United States)

    Dolbow, David R; Farley, Richard S; Kim, Jwa K; Caputo, Jennifer L

    2008-01-01

    The purpose of this study was to examine the cardiovascular responses to water treadmill walking at 2.0 mph (3.2 km/hr), 2.5 mph (4.0 km/hr), and 3.0 mph (4.8 km/hr) in older adults. Responses to water treadmill walking in 92 degrees F (33 degrees C) water were compared with responses to land treadmill walking at 70 degrees F (21 degrees C) ambient temperature. After an accommodation period, participants performed 5-min bouts of walking at each speed on 2 occasions. Oxygen consumption (VO2), heart rate (HR), systolic blood pressure (SBP), and rating of perceived exertion (RPE) were significantly higher during therapeutic water treadmill walking than during land treadmill walking. Furthermore, VO2, HR, and RPE measures significantly increased with each speed increase during both land and water treadmill walking. SBP significantly increased with each speed during water treadmill walking but not land treadmill walking. Thus, it is imperative to monitor HR and blood pressure for safety during this mode of activity for older adults. PMID:18212391

  9. Changes in Heart Rate Variability Parameters after Elective Percutaneous Coronary Intervention

    Science.gov (United States)

    Abrootan, Saeed; Yazdankhah, Saeed; Payami, Babak; Alasti, Mohammad

    2015-01-01

    Background: Patients with chronic stable angina often have a state of sympathetic hyperactivity. It is considered associated with myocardial ischemia and disappears after ischemia elimination. The aim of this study was to investigate the changes in heart rate variability parameters, a noninvasive technique for the evaluation of the autonomic nervous system activity, after successful revascularization in these patients to evaluate this theory. Methods: The patients were enrolled among those who underwent successful percutaneous coronary intervention. Short-term heart rate variability analyses of all the patients were obtained, and time-domain indices (standard deviation of normal-to-normal intervals [SDNN], standard deviation of differences of successive R-R intervals [SDSD], root-mean square differences of successive R-R intervals [rMSSD], percentage of R-R intervals differing > 10 ms from the preceding one [PNN10], percentage of R-R intervals differing > 20 ms from the preceding one [PNN20], percentage of R-R intervals differing > 30 ms from the preceding one [PNN30], percentage of R-R intervals differing > 40 ms from the preceding one [PNN40], percentage of R-R intervals differing > 50 ms from the preceding one [PNN50], percentage of R-R intervals differing > 60 ms from the preceding one [PNN60], and percentage of R-R intervals differing > 70 ms from the preceding one [PNN70]) were analyzed. All the measurements were made before and after percutaneous coronary intervention. Results: This study included 64 patients, comprising 27 men and 37 women at a mean age of 56.8 ± 9.1 years. There was a significant difference only between pre- and post-revascularization SDNN (27.5 ± 19.72 vs. 41 ± 41.4; p value = 0.013). The other parameters showed no significant differences after successful coronary intervention. Conclusion : Our data indicate that the increase in SDNN in patients with stable angina pectoris undergoing percutaneous coronary intervention seems to be prominent.

  10. Reduced Heart Rate Variability Is Associated With Increased Arterial Stiffness in Youth With Type 1 Diabetes

    Science.gov (United States)

    Jaiswal, Mamta; Urbina, Elaine M.; Wadwa, R. Paul; Talton, Jennifer W.; D’Agostino, Ralph B.; Hamman, Richard F.; Fingerlin, Tasha E.; Daniels, Stephen R.; Marcovina, Santica M.; Dolan, Lawrence M.; Dabelea, Dana

    2013-01-01

    OBJECTIVE Reduced heart rate variability (HRV) and increased arterial stiffness (AS) are both present in youth with type 1 diabetes. However, it is unclear whether they are associated and whether their association is independent of cardiovascular disease (CVD) risk factors. RESEARCH DESIGN AND METHODS The SEARCH Cardiovascular Disease (SEARCH CVD) study explored the cross-sectional relationships between HRV and several measures of AS in youth with (n = 344) and without (n = 171) type 1 diabetes. The SphygmoCor device (AtCor Medical, Sydney, Australia) was used to measure HRV using SD of normal R-R interval (SDNN), as well as AS, using pulse wave velocity in the carotid to femoral segment (PWV-trunk) and augmentation index adjusted to a heart rate of 75 bpm (AIx75). Brachial distensibility (BrachD), another index of AS, was measured with a DynaPulse instrument (Pulse Metric, San Diego, CA). Multiple linear regression analyses explored the associations between HRV and each of the three AS measures, after adjusting for demographic characteristics and traditional CVD risk factors (blood pressure, lipids, obesity, microalbuminuria, and smoking) separately, for youth with and without type 1 diabetes. RESULTS Among youth with type 1 diabetes, lower SDNN was associated with peripheral AS (lower BrachD, P = 0.01; r2 = 0.30) and central AS (higher PVW-trunk, P < 0.0001; r2 = 0.37; and higher AIx75, P = 0.007; r2 = 0.08). These associations were attenuated with adjustment for CVD risk factors, but remained statistically significant for BrachD and PWV-trunk. While a similar association between HRV and BrachD was present in control youth, lower HRV was not associated with increased central AS or with AIx75. CONCLUSIONS Longitudinal studies are needed to understand the pathways responsible for these associations. PMID:23435158

  11. Systolic reconstruction in patients with low heart rate using coronary dual-source CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru; Shigemoto, Youko; Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Miura, Toshiro; Nao, Tomoko [Department of Cardiology, Yamaguchi University Graduate School of Medicine (Japan); Sano, Yuichi; Narazaki, Akiko [Department of Radiology, Yamaguchi University Hospital (Japan); Kido, Shoji [Computer-aided Diagnosis and Biomedical Imaging Research Biomedical Engineering, Applied Medical Engineering Science Graduate School of Medicine, Yamaguchi University (Japan)

    2011-11-15

    Objectives: The purpose of our study was to determine the relationship between the predictive factors and systolic reconstruction (SR) as an optimal reconstruction window in patients with low heart rate (LHR; less than 65 bpm). Methods: 391 patients (262 male and 129 female, mean age; 67.1 {+-} 10.1 years of age) underwent coronary CTA without the additional administration of a beta-blocker. Affecting factors for SR were analyzed in age, gender, body weight (BW), diabetes mellitus (DM), coronary arterial disease (CAD), ejection fraction (EF), systolic and diastolic body pressure (BP) and heart rate variability (HRV) during coronary CTA. Results: In 29 (7.4%) of the 391 patients, SR was needed, but there was no apparent characteristic difference between the systolic and diastolic reconstruction groups in terms of gender, age, BW, DM, CAD and EF. In a multivariate analysis, the co-existence of DM [P < 0.05; OR, 0.27; 95% CI, 0.092-0.80], diastolic BP [P < 0.01; OR, 0.95; 95% CI, 0.92-0.98] and HRV [P < 0.01; OR, 0.98; 95% CI, 0.96-0.99] were found to be the factors for SR. In gender-related analysis, HRV was an important factor regardless of sex, but co-existence of DM affected especially for female and BP for male. Conclusion: Especially in the patients with LHR who had a medication of DM, high HRV or high BP, SR, in addition to DR, was needed to obtain high-quality coronary CTA images.

  12. ‘Fire of Life’ analysis of heart rate variability during alpine skiing in Austria

    Directory of Open Access Journals (Sweden)

    Gerhard Litscher

    2010-06-01

    Full Text Available Background: Skiing is a very popular sport in Austria. Nevertheless, there is little information concerning online monitoring of bio-signals during alpine skiing in the mountains. Within the last years innovative scientific monitoring tools for evaluating features of neurocardial fitness have been developed. Aims: The goal of this study was to demonstrate the new ‘Fire of Life’ heart rate variability analysis for the first time during alpine skiing. Volunteers and Methods: Continuous electrocardiographic monitoring over a period of 12 hours was performed simultaneously in two healthy volunteers using the same type of equipment (medilog AR12 systems. Two healthy volunteers (female, 20 years, and male, 51 years, both hobby skiers, were monitored simultaneously and continuously during two resting periods before and after active sport and also during alpine skiing. Altogether each participant covered 9,084 meters altitude difference within a time period of 6:14 hours. Total length of the downhill skiing was 45 kilometers. Results: Data acquisition was performed without any technical problems in both subjects. Poincaré plots of sequential R-R intervals (beat to beat variability show two ellipses of different shape and magnitude. During resting periods respiratory sinus arrhythmia and blood pressure effects can be clearly seen in the young female. The same effects, however markedly reduced, are obvious in the older volunteer. Conclusions: The present investigations during alpine skiing highlight the potential value of the ‘Fire of Life’ heart rate variability monitoring even under difficult environmental conditions. The innovative kind of analysis helps to show how well the human body reacts to sport, stress and recovery.

  13. Systolic reconstruction in patients with low heart rate using coronary dual-source CT angiography

    International Nuclear Information System (INIS)

    Objectives: The purpose of our study was to determine the relationship between the predictive factors and systolic reconstruction (SR) as an optimal reconstruction window in patients with low heart rate (LHR; less than 65 bpm). Methods: 391 patients (262 male and 129 female, mean age; 67.1 ± 10.1 years of age) underwent coronary CTA without the additional administration of a beta-blocker. Affecting factors for SR were analyzed in age, gender, body weight (BW), diabetes mellitus (DM), coronary arterial disease (CAD), ejection fraction (EF), systolic and diastolic body pressure (BP) and heart rate variability (HRV) during coronary CTA. Results: In 29 (7.4%) of the 391 patients, SR was needed, but there was no apparent characteristic difference between the systolic and diastolic reconstruction groups in terms of gender, age, BW, DM, CAD and EF. In a multivariate analysis, the co-existence of DM [P < 0.05; OR, 0.27; 95% CI, 0.092-0.80], diastolic BP [P < 0.01; OR, 0.95; 95% CI, 0.92-0.98] and HRV [P < 0.01; OR, 0.98; 95% CI, 0.96-0.99] were found to be the factors for SR. In gender-related analysis, HRV was an important factor regardless of sex, but co-existence of DM affected especially for female and BP for male. Conclusion: Especially in the patients with LHR who had a medication of DM, high HRV or high BP, SR, in addition to DR, was needed to obtain high-quality coronary CTA images.

  14. Assessment of the autonomic nervous injury by adriamycin using the analysis of heart rate variability

    International Nuclear Information System (INIS)

    Analysis of the heart rate variability were carried out for the cases with malignant tumors of the erythropoietic organ who received adriamycin (ADR), and the effects of ADR on the autonomic nervous of these patients were studied. Seven of 35 cases were examined for the consecutive heart rate variability and 123I-metaiodobenzylguanidine (MIBG) myocardial SPECT, after the administration of ADR. TP value, LF value, LF/HF and SDANN value were 1,448 msec2, 354 msec2, 2.0 and 97 msec, respectively, indicating that these values were significantly lower than the healthy controls (the C group) (P2 to 1,058 msec2, and HF value decreased from 191 msec2 to 123 msec2, significantly (P2, sympathetic nervous injury and parasympathetic nervous was caused by such dose ADR, when examinated by the analysis of the heart rate variability and MIBG myocardial SPECT. It is possible to estimate the myocardial injury of heart autonomic nervous that precedes the injury of heart muscle by ADR, by analyzing the heart rate variability, when the cases with malignant tumors are subject to thwith malignant tumors are subject to the chemotherapy. Thus it was suggested that the death by arrhythmia and the irreversible myocardial injury might be predictable. (author)

  15. Prognostic value of ambulatory heart rate revisited in 6928 subjects from 6 populations

    DEFF Research Database (Denmark)

    Hansen, Tine Willum; Thijs, Lutgarde

    2008-01-01

    The evidence relating mortality and morbidity to heart rate remains inconsistent. We performed 24-hour ambulatory blood pressure monitoring in 6928 subjects (not on beta-blockers; mean age: 56.2 years; 46.5% women) enrolled in prospective population studies in Denmark, Belgium, Japan, Sweden, Uruguay, and China. We computed standardized hazard ratios for heart rate, while stratifying for cohort, and adjusting for blood pressure and other cardiovascular risk factors. Over 9.6 years (median), 850, 325, and 493 deaths accrued for total, cardiovascular, and noncardiovascular mortality, respectively. The incidence of fatal combined with nonfatal end points was 805, 363, 439, and 324 for cardiovascular, stroke, cardiac, and coronary events, respectively. Twenty-four-hour heart rate predicted total (hazard ratio: 1.15) and noncardiovascular (hazard ratio: 1.18) mortality but not cardiovascular mortality (hazard ratio: 1.11) or any of the fatal combined with nonfatal events (hazard ratio: or =1.15) but none of the fatal combined with nonfatal events (hazard ratio: or =1.15) with the exception of stroke (hazard ratio: 1.06). Sensitivity analyses, in which we stratified by risk factors or from which we excluded 1 cohort at a time or the events occurring within 2 years of enrollment, showed consistent results. In the general population, heart rate predicts total and noncardiovascular mortality. With the exception of the night:day heart rate ratio, heart rate did not add to the risk stratification for fatal combined with nonfatal cardiovascular events. Thus, heart rate adds little to the predictionof cardiovascular risk Udgivelsesdato: 2008/8

  16. Sampling Rate of Heart Rate Variability Impacts the Ability to Detect Acidemia in Ovine Fetuses Near-Term

    OpenAIRE

    Durosier, L. Daniel; Green, Geoffrey; Batkin, Izmail; Seely, Andrew J.; Ross, Michael G.; Richardson, Bryan S.; Frasch, Martin G

    2014-01-01

    Background: To evaluate the impact of sampling rate on the predictive capability of continuous fetal heart rate (FHR) variability (fHRV) monitoring for detecting fetal acidemia during labor, we tested the performance of the root mean square of successive differences (RMSSD) in R–R intervals from the ECG when acquired with the sampling rate of 4?Hz currently available in FHR monitors, in comparison to the gold standard of 1000?Hz.

  17. Resting Sinus Heart Rate and First Degree AV block: Modifiable Risk Predictors or Epiphenomena?

    OpenAIRE

    Rakesh Gopinathannair; Brian Olshansky

    2009-01-01

    Simple and cost-effective tools that identify patients at increased risk for adverse cardiovascular events are actively sought. High resting sinus heart rate and first degree AV block are easily recognized and commonly encountered findings in a cardiology practice. A growing body of epidemiological and clinical evidence has been shown them to be independent predictors of all-cause and cardiovascular mortality, both in the general population and in patients with structural heart disease. This ...

  18. Effects of clonidine on canine cardiac neuroeffector structures controlling heart rate

    OpenAIRE

    Cavero, I.; Roach, A. G.

    1980-01-01

    1 In intact dogs anaesthetized with pentobarbitone, clonidine (10 ?g/kg, i.v.) produced a sustained decrease in heart rate. This effect was significantly smaller in vagotomized dogs in which the sympathetic drive to the heart was either left intact or experimentally created by continuous electrical stimulation of the decentralized cardioaccelerator nerve. In the latter preparation, the negative chronotropic action of clonidine was reversed by an intravenous injection of phentolamine, whereas...

  19. Evaluation of three-dimensional navigator-gated whole heart MR coronary angiography: The importance of systolic imaging in subjects with high heart rates

    International Nuclear Information System (INIS)

    Purpose: To evaluate the influence of heart rate (HR) on magnetic resonance coronary angiography (MRCA) image quality in diastolic and systolic phases. Materials and methods: Twenty-seven healthy volunteers (9 men; 33 ± 9 years, HR 53-110 bpm), were evaluated with the electrocardiography and three-dimensional navigator-gating MRCA in a 1.5-T MR scanner (Avanto, Siemens) in diastolic and systolic phases (steady-state free precession; TR/TE/flip angle = 3.2 ms/1.6 ms/90o). The timing of scanning was individually adapted to the cardiac rest periods obtained in the prescanning, by visually identifying when the movement of right coronary artery was minimized during diastole and systole. Images of two phases were side-by-side compared on a four-point scale (from 1 = poor to 4 = excellent visibility; score of 3 or 4 as diagnostic). Results: Of 13 subjects with HR ?65 bpm (low HR group, mean 59.8 ± 4.9 bpm, range 53-65), the image quality scores were significantly better than that with higher heart rates (73.9 ± 9.0 bpm, range 68-110) in diastolic MRCA. The image quality was significantly improved during systole in high HR group. Overall, 91.3% of low HR group had MRCA image of diagnostic quality acquired at diastole, while 88.3% of high HR group had diagnostic images at systole by segmental analysis (p = NS). Conclusions: MRCA at systole offered superior quality in patients with high heart rates

  20. Sleep Stage Dependence of Invariance Characteristics in Fluctuations of Healthy Human Heart Rate

    Science.gov (United States)

    Togo, Fumiharu; Kiyono, Ken; Struzik, Zbigniew R.; Yamamoto, Yoshiharu

    2005-08-01

    The outstanding feature of healthy human heart rate is the robust scale invariance in the non-Gaussian probability density function (PDF), which is preserved not only in a quiescent condition, but also in a dynamic state during waking hours [K. Kiyono et al. Phys. Rev. Lett. 93 (2004)]. Together with 1/f like scaling, this characteristic is a strong indication of far-from-equilibrium, critical-like dynamics of heart rate regulation. Our results suggest that healthy human heart rate departs from a critical state-like operation during sleeping hours, at a rate which is heterogeneous with respect to sleep stages annotated according to traditional techniques. We study specific contributions of sleep stages to the relative departure from criticality through the analysis of sleep stage dependence of the root mean square of multiscale local energy and the multiscale PDF. There is a possibility that the involvement of cortical activity may be important for a critical state-like operation.

  1. High readmission rate after heart valve surgery : A nationwide cohort study

    DEFF Research Database (Denmark)

    Sibilitz, K L; Berg, S K

    2015-01-01

    BACKGROUND: After heart valve surgery, knowledge on long-term self-reported health status and readmission is lacking. Thus, the optimal strategy for out-patient management after surgery remains unclear. METHODS: Using a nationwide survey with linkage to Danish registers with one year follow-up, we included all adults 6-12months after heart valve surgery irrespective of valve procedure, during Jan-June 2011 (n=867). Participants completed a questionnaire regarding health-status (n=742), and answers were compared with age- and sex-matched healthy controls. Readmission rates and mortality were investigated. RESULTS: After valve surgery, the self-reported health was lower (Short Form-36 (SF-36) Physical Component Scale (PCS): 44.5 vs. 50.6 and Mental Component Scale (MCS): 51.9 vs. 55.0, p<0.0001) and more were physically sedentary compared with healthy controls (11.1% vs. 15.2%). Clinical signs of anxiety and depression were present in 13.6% and 13.8%, respectively (Hospital Anxiety and Depression Scale score?8). Twelve months following discharge, 483 persons (56%) were readmitted. Readmission was associated with lower self-reported health (SF-36 PCS: 46.5 vs. 43.9, and MCS 52.2 vs. 50.7). Higher age (hazard ratio (95% CI): 1.3 (1.0-1.6)), male sex (1.2 (1.0-1.5)), mitral valve surgery (1.3 (1.0-1.6)), and infective endocarditis after surgery (1.8 (1.1-3.0), p: 0.01) predicted readmission, whereas higher age (2.3 (1.0-5.4)), higher comorbidity score (3.2 (1.8-6.0)), and infective endocarditis after surgery (3.2 (1.2-8.9)) predicted mortality. CONCLUSIONS: 6-12months after heart valve surgery the readmission rate is high and the self-reported health status is low. Readmission is associated with low self-reported health. Therefore, targeted follow-up strategies post-surgery are needed.

  2. Effect of amlodipine and of nifedipine retard on autonomic regulation of heart rate in elderly patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    E.D. Golovanova

    2008-01-01

    Full Text Available Aim. To study the effect of the monotherapy with calcium channel blockers (amlodipine, 5 mg/d and nifedipine retard, 40 mg/d on heart rate variability (HRV in elderly hypertensive patients with different rate of biological ageing.Material and methods. 55 male hypertensive patients of 60-86 years with ischemic heart disease and chronic heart failure, class I-III (NYHA, were examined. Biological age was determined by the linear regression. HRVwas determined by cardiointervalography and variation pulsemetry at the rest and in orthostatic test. Patientswere split in to 2 groups (I - normal; II - fast ageing rate and treated with the investigated drugs for 4 weeks. At the baseline and at the end of the study HRV and clinical blood pressure (BP were determined.Results. Normal sympathetic activity and moderate overactivity was observed in patients of I group, and prominent sympathetic overactivity - in patients of II group. Monotherapywith amlodipine in patients of I and II groups improved indices of HRV (variation range, dispersion and stress index and provided target BP reduction.Monotherapywith nifedipine retard in patients of I group elevated variation range, decreased stress index and provided target BP reduction. Sympathetic activity was not changed in patients of the II group. Autonomic regulation was normalized due to amlodipine and nifedipine retard therapy in patients of the both groups.Conclusion. The sympathetic overactivity is observed in elderly hypertensive patients. Monotherapy with calcium blockers improves HRV and provides target BP reduction.

  3. Drawing Conclusions

    Science.gov (United States)

    Michael P. Klentschy

    2008-04-01

    Drawing conclusions involves comparing initial ideas with new evidence and then deciding whether the ideas fit or need to be changed. It is the key to the investigation, where mental and practical activity comes together. This is how scientists approach i

  4. Changes in Blood Pressure and Heart Rate during Fixed-Interval Responding in Squirrel Monkeys

    Science.gov (United States)

    DeWeese, Jo

    2009-01-01

    Episodic and sustained increases in heart rate and mean arterial blood pressure can occur with recurring patterns of schedule-controlled behavior. Most previous studies were conducted under fixed-ratio schedules, which maintained a consistent high rate of responding that alternated with periods of no responding during times when the schedule was…

  5. Heart rate and behavioural responses of crib-biting horses to two acute stressors.

    Science.gov (United States)

    Minero, M; Canali, E; Ferrante, V; Verga, M; Odberg, F O

    1999-10-01

    The heart rate and behaviour of 14 adult saddle horses, eight crib-biters and six normal controls, were investigated. Initially, the relationship between crib-biting and heart rate was investigated while the horses were undisturbed. The horses were tested when restrained with a lip twitch, and assessed when they were exposed suddenly to the rapid inflation of a balloon. The heart rate of the crib-biters during crib-biting was lower than during other behaviours. The crib-biters had a higher overall mean heart rate (Phorses had a transient increase in heart rate which returned to basal values more rapidly in the crib-biters. The crib-biters were less reactive to the lip twitch, five of the six investigated remaining calm, and after the release of the twitch, they spent more time nibbling (Phorses. The crib-biters reacted more strongly to the inflation of the balloon (three of the six reacted), and after it had been inflated they spent more time walking in the box. PMID:10755589

  6. New Cardiovascular Risk Factors; Resting Heart Rate, Hs-CRP, Fibrinogen and PMNL

    Directory of Open Access Journals (Sweden)

    Mehmet Aktu?lu

    2012-01-01

    Full Text Available Aim: In this study we aimed to evaluate the possibility of a presence of an association between the high resting heart rate and micro inflammatory response and with the help of any found, clarify the recently identified negative cardiovascular prognosis in individuals with high resting heart rate from an etiological point of view. Material and Method: Study was conducted in September, 2009 with a total of 67 male cases consisting of 36 cases that are followed up at Haseki Egt. ve Ars. Hospital Cardiology Outpatient and Coronary Intensive Care Clinic and 31 cases included in the control group. Patient and control groups were compared regarding age, body mass index, systolic and diastolic blood pressure, leukocyte count, hs-CRP and fibrinogen levels, coronary risk factors and resting heart rates. Result: Significant difference was seen between resting heart rate, smoking and positive family history. There were statistically significant differences between the patient group and the control group regarding systolic and diastolic blood pressure, leukocyte count, hs-CRP and fibrinogen levels and resting heart rates (p

  7. Stochastic analysis of heart rate variability and its relation to echocardiography parameters in hypertrophic cardiomyopathy patients

    International Nuclear Information System (INIS)

    The heart rate variability of 10 healthy males (age 26 ? 4/+ 3 y) and 49 patients with hypertrophic cardiomyopathy (HCM) (25 males, 24 females, age 29.5 ? 11.5/+ 10.5 y) was studied. We applied Kramers–Moyal expansion to extract the drift and diffusion terms of the Langevin equation for the RR interval time series. These terms may be used for a stochastic reconstruction of the time series and for description of the properties of heart rate variability. New parameters characterizing the diffusion term are proposed: the coefficients of the linear fit to the left (LCF) and right (RCF) branch of the dependence of the diffusion term on the rescaled heart rate. Relations of the new parameters to classical echocardiography parameters were studied. Using the relation between the difference LCF–RCF and the left ventricular systolic diameter, the HCM patients studied were divided into three groups. In addition, comparison of the properties of the heart rate variability in the HCM group with that obtained for the healthy young men showed that the parameter LCF–RCF may be treated as a measure of the effect of HCM on heart rate variability and may have diagnostic value

  8. Influence of mercury exposure on blood pressure, resting heart rate and heart rate variability in French Polynesians: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Valera Beatriz

    2011-11-01

    Full Text Available Abstract Background Populations which diet is rich in seafood are highly exposed to contaminants such as mercury, which could affect cardiovascular risk factors Objective To assess the associations between mercury and blood pressure (BP, resting heart rate (HR and HR variability (HRV among French Polynesians Methods Data were collected among 180 adults (? 18 years and 101 teenagers (12-17 years. HRV was measured using a two-hour ambulatory electrocardiogram (Holter and BP was measured using a standardized protocol. The association between mercury and HRV and BP parameters was studied using analysis of variance (ANOVA and analysis of covariance (ANCOVA Results Among teenagers, the high frequency (HF decreased between the 2nd and 3rd tertile (380 vs. 204 ms2, p = 0.03 and a similar pattern was observed for the square root of the mean squared differences of successive R-R intervals (rMSSD (43 vs. 30 ms, p = 0.005 after adjusting for confounders. In addition, the ratio low/high frequency (LF/HF increased between the 2nd and 3rd tertile (2.3 vs. 3.0, p = 0.04. Among adults, the standard deviation of R-R intervals (SDNN tended to decrease between the 1st and 2nd tertile (84 vs. 75 ms, p = 0.069 after adjusting for confounders. Furthermore, diastolic BP tended to increase between the 2nd and 3rd tertile (86 vs. 91 mm Hg, p = 0.09. No significant difference was observed in resting HR or pulse pressure (PP Conclusions Mercury was associated with decreased HRV among French Polynesian teenagers while no significant association was observed with resting HR, BP, or PP among teenagers or adults

  9. The influence of subclinical hyperthyroidism on blood pressure, heart rate variability and incidence of arrhythmia.

    Science.gov (United States)

    Kami?ski, Grzegorz Wiktor; Makowski, Karol; Michalkiewicz, Dariusz; Kowal, Jaroslaw; Ruchala, Marek; Szczepanek, Ewelina; Gielerak, Grzegorz

    2012-01-20

    Background: The impact of subclinical hyperthyroidism (sHT) on the cardiovascular system still needs to be elucidated. The aim of the study was to prospectively assess blood pressure, variability in heart rate, and the prevalence of arrhythmias in patients with sHT, both before and after they are restored to the euthyroid state. Methods: The study group consisted of 44 normotensive patients (37 women, 7 men), aged 22-65 years (mean±SD: 45.9±11.0) with sHT. Enrolled patients were drawn from 1080 patients referred to our department for treatment of hyperthyroidism. Study patients were treated with radioiodine treatment to restore the euthyroid state. Ambulatory blood pressure monitoring (ABPM) and Holter electrocardiography were performed (1) when sHT was diagnosed and (2) at least 6 months after they became euthyroid. Results: sHT in comparison to euthyroid state was associated with higher (109.3±7.1 vs 107.1±7.7 mmHg) nocturnal systolic mean blood pressure (p=0.035) and blood pressure (BP) load (14.8 vs 10.2 %, p=0.033), mean diastolic BP (66.4±6.6 vs 64.8±6.6 mmHg, p=0.047) and mean arterial pressure (80.8±43.1 vs 79.3±43.6 mmHg, p=0.049). Moreover, significant changes in both the time and frequency domain measures of heart rate variability were observed: decrease of the square root of the mean squared differences of successive NN intervals (rMSSD) - 45.68±34.1 vs 65.09±50.6 ms (p=0.03) and the low frequency power (LF) - 5.71±0.99 vs 6.0±1.01 ms2 (p=0.049) as well as increase of QT interval dispersion - 58.25±28.5 vs 46.90±12.1 ms (p=0.020). This was accompanied by clinically insignificant increase in the frequency of ventricular extrasystoles (VES) - 3.1±7.4 vs 0.6±1.2 per hour (p=0.048) and increased mean heart rate - 78.4±6.8 vs 76.0±8.0 beats/min (p=0.004). Some of the parameters correlated positively with thyroid hormones: nocturnal diastolic BP with FT3 (r=0.397, p=0.008), rMSSD with FT4 (r=0.389, p=0.013) and QT interval dispersion with FT4 (r=0.450, p=0.004). Conclusions: The study suggests that sHT in comparison to euthyroid status may be associated with a statistically significant but probably clinically insignificant increase of QT interval dispersion, prevalence of VES, elevated nocturnal arterial BP and changes in heart rate variability. These findings broaden our understanding of the cardiovascular effects of sHT. PMID:22263581

  10. Effect of verapamil on heart rate variability after an acute myocardial infarction. Danish Verapamil Infarction Trial II.

    DEFF Research Database (Denmark)

    Vaage-Nilsen, M; Rasmussen, Verner

    1998-01-01

    Because decreased heart rate variability measured after an acute myocardial infarction (AMI) has been demonstrated to predict subsequent mortality and sudden death, and an efficacy analysis of the Danish Verapamil Infarction Trial II (DAVIT II) demonstrated that long-term postinfarction treatment with verapamil significantly reduced sudden death, the aim of the present substudy was to evaluate the effect of verapamil on heart-rate variability in the time and frequency domain, measured in two 5-minute segments during the day and night. Thirty-eight patients were examined by Holter monitoring, at 1 week, that is, before randomization, and at 1 month after infarction; 22 of the patients were examined 12-16 months after infarction as well. In both treatment groups (verapamil and placebo) no significant alteration of heart rate variability during the day-time was demonstrated from before to after 1 and 12-16 months of treatment. In accord with the known reduction of overall heart rate by verapamil, a significant increase of mean NN interval from before to after 1 (P = 0.0004) and 12-16 months (P = 0.004) of treatment was seen in the verapamil, but not in the placebo, group at night. Parameters generally interpreted as an index of parasympathetic modulation, that is, RMSSD, pNN50, and high-frequency power, increased significantly at 1 month (P = 0.04, P = 0.03, NS, respectively) and 12-16 months (P = 0.03, P = 0.04, P < 0.05) after AMI in the verapamil, but not in the placebo, group. In conclusion, the present study indicates that verapamil shifts the autonomic balance to a vagal preponderance or sympathetic attenuation in the postinfarction period.

  11. Low doses of caffeine reduce heart rate during submaximal cycle ergometry

    Directory of Open Access Journals (Sweden)

    Wetter Thomas J

    2007-10-01

    Full Text Available Abstract Background The purpose of this study was to examine the cardiovascular effects of two low-levels of caffeine ingestion in non habitual caffeine users at various submaximal and maximal exercise intensities. Methods Nine male subjects (19–25 yr; 83.3 ± 3.1 kg; 184 ± 2 cm, underwent three testing sessions administered in a randomized and double-blind fashion. During each session, subjects were provided 4 oz of water and a gelatin capsule containing a placebo, 1.5 mg/kg caffeine, or 3.0 mg/kg caffeine. After thirty minutes of rest, a warm-up (30 Watts for 2 min the pedal rate of 60 rpm was maintained at a steady-state output of 60 watts for five minutes; increased to 120 watts for five minutes and to 180 watts for five minutes. After a 2 min rest the workload was 180 watts for one minute and increased by 30 watts every minute until exhaustion. Heart rate (HR was measured during the last 15-seconds of each minute of submaximal exercise. Systolic blood pressure (BP was measured at rest and during each of the three sub-maximal steady state power outputs. Minute ventilation (VE, Tidal volume (VT, Breathing frequency (Bf, Rating of perceived exertion (RPE, Respiratory exchange ratio (RER, and Oxygen consumption (VO2 were measured at rest and during each minute of exercise. Results Caffeine at 1.5 and 3.0 mg/kg body weight significantly lowered (p E, VT, VO2, RPE, maximal power output or time to exhaustion. Conclusion In non habitual caffeine users it appears that consuming a caffeine pill (1.5 & 3.0 mg/kg at a dose comparable to 1–3 cups of coffee lowers heart rate during submaximal exercise but not at near maximal and maximal exercise. In addition, this caffeine dose also only appears to affect systolic blood pressure at rest but not during cycling exercise.

  12. Influence of mercury exposure on blood pressure, resting heart rate and heart rate variability in French Polynesians: a cross-sectional study

    OpenAIRE

    Valera Beatriz; Dewailly Éric; Poirier Paul; Counil Emilie; Suhas Edouard

    2011-01-01

    Abstract Background Populations which diet is rich in seafood are highly exposed to contaminants such as mercury, which could affect cardiovascular risk factors Objective To assess the associations between mercury and blood pressure (BP), resting heart rate (HR) and HR variability (HRV) among French Polynesians Methods Data were collected among 180 adults (? 18 years) and 101 teenagers (12-17 years). HRV was measured using a two-hour ambulatory electrocardiogram (Holter) and BP was measured...

  13. Role of genetic and environmental influences on heart rate variability in middle-aged men.

    Science.gov (United States)

    Uusitalo, A L T; Vanninen, E; Levälahti, E; Battié, M C; Videman, T; Kaprio, J

    2007-08-01

    Our aim was to estimate causal relationships of genetic factors and different specific environmental factors in determination of the level of cardiac autonomic modulation, i.e., heart rate variability (HRV), in healthy male twins and male twins with chronic diseases. The subjects were 208 monozygotic (MZ, 104 healthy) and 296 dizygotic (DZ, 173 healthy) male twins. A structured interview was used to obtain data on lifetime exposures of occupational loading, regularly performed leisure-time sport activities, coffee consumption, smoking history, and chronic diseases from 12 yr of age through the present. A 5-min ECG at supine rest was recorded for the HRV analyses. In univariate statistical analyses based on genetic models with additive genetic, dominance genetic, and unique environmental effects, genetic effects accounted for 31-57% of HRV variance. In multivariate statistical analysis, body mass index, percent body fat, coffee consumption, smoking, medication, and chronic diseases were associated with different HRV variables, accounting for 1-11% of their variance. Occupational physical loading and leisure-time sport activities did not account for variation in any HRV variable. However, in the subgroup analysis of healthy and diseased twins, occupational loading explained 4% of the variability in heart periods. Otherwise, the interaction between health status and genetic effects was significant for only two HRV variables. In conclusion, genetic factors accounted for a major portion of the interindividual differences in HRV, with no remarkable effect of health status. No single behavioral determinant appeared to have a major influence on HRV. The effects of medication and diseases may mask the minimal effect of occupational loading on HRV. PMID:17400723

  14. Multiscale multifractal analysis of heart rate variability recordings with a large number of occurrences of arrhythmia.

    Science.gov (United States)

    Giera?towski, J; ?ebrowski, J J; Baranowski, R

    2012-02-01

    Human heart rate variability, in the form of time series of intervals between heart beats, shows complex, fractal properties. Recently, it was demonstrated many times that the fractal properties vary from point to point along the series, leading to multifractality. In this paper, we concentrate not only on the fact that the human heart rate has multifractal properties but also that these properties depend on the time scale in which the multifractality is measured. This time scale is related to the frequency band of the signal. We find that human heart rate variability appears to be far more complex than hitherto reported in the studies using a fixed time scale. We introduce a method called multiscale multifractal analysis (MMA), which allows us to extend the description of heart rate variability to include the dependence on the magnitude of the variability and time scale (or frequency band). MMA is relatively immune to additive noise and nonstationarity, including the nonstationarity due to inclusions into the time series of events of a different dynamics (e.g., arrhythmic events in sinus rhythm). The MMA method may provide new ways of measuring the nonlinearity of a signal, and it may help to develop new methods of medical diagnostics. PMID:22463252

  15. Evaluation of sympathetic nerve system activity with MIBG. Comparison with heart rate variability

    International Nuclear Information System (INIS)

    Authors attempted to elucidate the relations of plasma concentration of norepinephrine (pNE) and findings of heart rate variability and MIBG myocardial scintigraphy and evaluated cardiac autonomic nervous activity in chronic renal failure. Subjects were 211 patients with various heart diseases (coronary artery lesion, cardiomyopathy, hypertension, diabetes mellitus, renal failure and so on), 60 patients with artificial kidney due to chronic renal failure, 13 of whom were found to have coronary arterial disease by Tl myocardial scintigraphy, and 14 normal volunteers. ECG was recorded with the portable recorder for heart rate variability. Together with collection of blood for pNE measurement, myocardial scintigraphy was done at 15 and 150 min after intravenous administration of 111 MBq of MIBG for acquisition of early and delayed, respectively, images of the frontal breast. Accumulation at and elimination during the time points of MIBG were computed in cps unit. Variability of heart rate was found to have the correlation positive with MIBG delayed accumulation and negative with the elimination, and pNE, negative with heart rate variability and the delayed accumulation and positive with the elimination. Thus cardiac autonomic nervous abnormality was suggested to occur before uremic cardiomyopathy. (K.H.)

  16. Heart wall motion analysis by dynamic 3D strain rate imaging from tissue Doppler echocardiography

    Science.gov (United States)

    Hastenteufel, Mark; Wolf, Ivo; de Simone, Raffaele; Mottl-Link, Sibylle; Meinzer, Hans-Peter

    2002-04-01

    The knowledge about the complex three-dimensional (3D) heart wall motion pattern, particular in the left ventricle, provides valuable information about potential malfunctions, e.g., myocardial ischemia. Nowadays, echocardiography (cardiac ultrasound) is the predominant technique for evaluation of cardiac function. Beside morphology, tissue velocities can be obtained by Doppler techniques (tissue Doppler imaging, TDI). Strain rate imaging (SRI) is a new technique to diagnose heart vitality. It provides information about the contraction ability of the myocardium. Two-dimensional color Doppler echocardiography is still the most important clinical method for estimation of morphology and function. Two-dimensional methods leads to a lack of information due to the three-dimensional overall nature of the heart movement. Due to this complex three-dimensional motion pattern of the heart, the knowledge about velocity and strain rate distribution over the whole ventricle can provide more valuable diagnostic information about motion disorders. For the assessment of intracardiac blood flow three-dimensional color Doppler has already shown its clinical utility. We have developed methods to produce strain rate images by means of 3D tissue Doppler echocardiography. The tissue Doppler and strain rate images can be visualized and quantified by different methods. The methods are integrated into an interactively usable software environment, making them available in clinical everyday life. Our software provides the physician with a valuable tool for diagnosis of heart wall motion.

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

    Science.gov (United States)

    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 assessment protocol. PMID:25690105

  18. The relationship between oxygen uptake reserve and heart rate reserve is affected by intensity and duration during aerobic exercise at constant work rate.

    Science.gov (United States)

    Cunha, Felipe A; Midgley, Adrian W; Monteiro, Walace D; Campos, Felipe K; Farinatti, Paulo T V

    2011-12-01

    The relationship between the percentage of heart rate reserve (%HRR) and percentage of oxygen uptake reserve (%VO?R) has been recommended for prescribing aerobic exercise intensity. However, this relationship was derived from progressive maximal exercise testing data, and the stability of the relationship during prolonged exercise at a constant work rate has not been established. The main aim of this study was to investigate the stability of the %VO?R-%HRR relationship during prolonged treadmill exercise bouts performed at 3 different constant work rates. Twenty-eight men performed 4 exercise tests: (i) a ramp-incremental maximal exercise test to determine maximal heart rate (HR(max)) and maximal oxygen uptake (VO?(max)) and (ii) three 40-min exercise bouts at 60%, 70%, and 80% VO?R. HR and VO? significantly increased over time and were influenced by exercise intensity (p ACSM running equation were all significantly higher than the observed VO? values (p < 0.001 for all comparisons), whereas a difference for HR was observed only for the tenth min of exercise at 80% VO?R (p = 0.041). In conclusion, the main finding of this study was that the %HRR-%VO?R relationship determined by linear regression, obtained from progressive maximal exercise testing, did not apply to prolonged treadmill running performed at 3 work rates. PMID:22034854

  19. Effect of Training Mode on Post-Exercise Heart Rate Recovery of Trained Cyclists

    Directory of Open Access Journals (Sweden)

    McDonald Kelia G.

    2014-07-01

    Full Text Available The sympathetic nervous system dominates the regulation of body functions during exercise. Therefore after exercise, the sympathetic nervous system withdraws and the parasympathetic nervous system helps the body return to a resting state. In the examination of this relationship, the purpose of this study was to compare recovery heart rates (HR of anaerobically versus aerobically trained cyclists. With all values given as means ± SD, anaerobically trained track cyclists (n=10, age=25.9 ± 6.0 yrs, body mass=82.7 ± 7.1 kg, body fat=10.0 ± 6.3% and aerobically trained road cyclists (n=15, age=39.9 ± 8.5 yrs, body mass=75.3 ± 9.9 kg, body fat=13.1 ± 4.5% underwent a maximal oxygen uptake test. Heart rate recovery was examined on a relative basis using heart rate reserve as well as the absolute difference between maximum HR and each of two recovery HRs. The post-exercise change in HR at minute one for the track cyclists and road cyclists respectively were 22 ± 8 bpm and 25 ± 12 bpm. At minute two, the mean drop for track cyclists was significantly (p<0.05 greater than the road cyclists (52 ± 15 bpm and 64 ± 11 bpm. Training mode showed statistically significant effects on the speed of heart rate recovery in trained cyclists. Greater variability in recovery heart rate at minute two versus minute one suggests that the heart rate should be monitored longer than one minute of recovery for a better analysis of post-exercise autonomic shift.

  20. Effects of Dietary Salt on Blood Pressure, Heart Rate, Extracellular Fluid Volume and Glomerular Filtration Rate in Diabetic Rats

    OpenAIRE

    ÖZAYKAN, Besim

    1999-01-01

    In the present study, we aimed to investigate the effects of dietary salt restriction and loading on extracellular fluid volume (ECFV), blood pressure (BP), heart rate (HR), glomerular filtration rate (GFR) and renal hypertrophy in diabetic rats. Diabetes was induced by injection of streptozotocin (STZ, 65 mg/kg, iv) into male Wistar rats. Four groups were formed: a) the diabetic rats given a standard rat diet (DC), b) the diabetic rats given a high-salt diet (DHS), c) the diabetic...

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  2. Evaluation of the influence of change in heart rate on left ventricular diastolic function indices

    International Nuclear Information System (INIS)

    In order to assess the influence of change in heart rate on left ventricular diastolic function indices, ECG gated cardiac pool study was performed in 6 patients with implanted programmable AAI pacemakers. Heart rate was changed by atrial pacing from 50 to 120 beats/min, every 10 beats/min. The filling fraction during first third of diastole (1/3FF), the peak filling rate (PFR), mean first third filling rate (1/3FR-mean) and early filling volume ratio (%EFV), being used as the indices of left ventricular diastolic performance, were assessed. In accordance with increase in heart rate, 1/3FF decreased significantly. PFR were fairly stable from 50 to 80 beats/min, but increased significantly from 90 to 120 beats/min. 1/3FR-mean and %EFV did not change significantly, but 1/3FR-mean showed decreasing tendency and %EFV showed increasing tendency as the heart rate was increased. %EFV was more changeable index than other indices among clinical cases. These results indicate that PFR and 1/3FR-mean were appropriate diastolic phase indices at rest. (author)

  3. Heart rate variability and short duration spaceflight: relationship to post-flight orthostatic intolerance

    Directory of Open Access Journals (Sweden)

    Blaber Andrew P

    2004-04-01

    Full Text Available Abstract Background Upon return from space many astronauts experience symptoms of orthostatic intolerance. Research has implicated altered autonomic cardiovascular regulation due to spaceflight with further evidence to suggest that there might be pre-flight autonomic indicators of post-flight orthostatic intolerance. We used heart rate variability (HRV to determine whether autonomic regulation of the heart in astronauts who did or did not experience post-flight orthostatic intolerance was different pre-flight and/or was differentially affected by short duration (8 – 16 days spaceflight. HRV data from ten-minute stand tests collected from the 29 astronauts 10 days pre-flight, on landing day and three days post-flight were analysed using coarse graining spectral analysis. From the total power (PTOT, the harmonic component was extracted and divided into high (PHI: >0.15 Hz and low (PLO: = 0.15 Hz frequency power regions. Given the distribution of autonomic nervous system activity with frequency at the sinus node, PHI/PTOT was used as an indicator of parasympathetic activity; PLO/PTOT as an indicator of sympathetic activity; and, PLO/PHI as an estimate of sympathovagal balance. Results Twenty-one astronauts were classified as finishers, and eight as non-finishers, based on their ability to remain standing for 10 minutes on landing day. Pre-flight, non-finishers had a higher supine PHI/PTOT than finishers. Supine PHI/PTOT was the same pre-flight and on landing day in the finishers; whereas, in the non-finishers it was reduced. The ratio PLO/PHI was lower in non-finishers compared to finishers and was unaffected by spaceflight. Pre-flight, both finishers and non-finishers had similar supine values of PLO/PTOT, which increased from supine to stand. Following spaceflight, only the finishers had an increase in PLO/PTOT from supine to stand. Conclusions Both finishers and non-finishers had an increase in sympathetic activity with stand on pre-flight, yet only finishers retained this response on landing day. Non-finishers also had lower sympathovagal balance and higher pre-flight supine parasympathetic activity than finishers. These results suggest pre-flight autonomic status and post-flight impairment in autonomic control of the heart may contribute to orthostatic intolerance. The mechanism by which higher pre-flight parasympathetic activity might contribute to post-flight orthostatic intolerance is not understood and requires further investigation.

  4. Association of resting heart rate with carotid and aortic arterial stiffness: Multi-Ethnic Study of Atherosclerosis (MESA)

    OpenAIRE

    Whelton, Seamus P.; Blankstein, Ron; Al–mallah, Mouaz H.; Lima, Joao A. C.; Bluemke, David A.; Hundley, W. Gregory; Polak, Joseph F.; Blumenthal, Roger S.; Nasir, Khurram; Blaha, Michael J.

    2013-01-01

    Resting heart rate is an easily measured, non-invasive vital sign that is associated with cardiovascular disease events. The pathophysiology of this association is not known. We investigated the relationship between resting heart rate and stiffness of the carotid (a peripheral artery) and the aorta (a central artery) in an asymptomatic multi-ethnic population. Resting heart rate was recorded at baseline in the Multi-Ethnic Study of Atherosclerosis (MESA). Distensibility was used as a measure ...

  5. Resting heart rate as a tool for risk stratification in primary care: does it provide incremental prognostic information?

    OpenAIRE

    Leistner, David M.; Klotsche, Jens; Palm, Sylvia; Pieper, Lars; Stalla, Gu?nter K.; Lehnert, Hendrik; Silber, Sigmund; Ma?rz, Winfried; Wittchen, Hans-ulrich; Zeiher, Andreas M.

    2013-01-01

    Background: Several selected population-based studies have emphasized the significance of resting heart rate as an independent cardiovascular risk factor. However, there are no data available for using resting heart rate as a cardiovascular risk predictor in contemporary primary care. Thus, the aim of our analysis was to examine the clinical value of the measurement of resting heart rate in a large, unselected population-based cohort of primary care subjects under the conditions of contempora...

  6. Field test of a paradigm: hysteresis of heart rate in thermoregulation by a free-ranging lizard (Pogona barbata).

    OpenAIRE

    Grigg, G. C.; Seebacher, F

    1999-01-01

    The discovery that changes in heart rate and blood flow allow some reptiles to heat faster than they cool has become a central paradigm in our understanding of reptilian thermoregulation. However, this hysteresis in heart rate has been demonstrated only in simplistic laboratory heating and cooling trials, leaving its functional significance in free-ranging animals unproven. To test the validity of this paradigm, we measured heart rate and body temperature (Tb) in undisturbed, free-ranging bea...

  7. Heart rate variability predicts cell death and inflammatory responses to global cerebral ischemia

    Directory of Open Access Journals (Sweden)

    GregNorman

    2012-05-01

    Full Text Available This study examines the relationship between autonomic functioning and neuropathology following cardiac arrest in mice. Within 24h of cardiac arrest, parasympathetic cardiac control, as indexed by heart rate variability (HRV, rapidly decreases. By day 7 after cardiac arrest, HRV is inversely correlated with neuronal damage and microglial activation in the hippocampus. Thus, by virtue of its sensitivity to central insult, HRV may offer an inexpensive, noninvasive method of monitoring neuropathological processes following cardiac arrest. The inverse linear relationships between HRV and brain damage after cardiac arrest also may partially explain why low heart rate variability is associated with increased morbidity and mortality in myocardial infarction patients.

  8. Heart rate variability in athletes and nonathletes at rest and during head-up tilt

    Scientific Electronic Library Online (English)

    F.S., Martinelli; M.P.T., Chacon-Mikahil; L.E.B., Martins; E.C., Lima-Filho; R., Golfetti; M.A., Paschoal; L., Gallo-Junior.

    2005-04-01

    Full Text Available The purpose of the present study was to determine if autonomic heart rate modulation, indicated by heart rate variability (HRV), differs during supine rest and head-up tilt (HUT) when sedentary and endurance-trained cyclists are compared. Eleven sedentary young men (S) and 10 trained cyclists (C) we [...] re studied. The volunteers were submitted to a dynamic ECG Holter to calculate HRV at rest and during a 70º HUT. The major aerobic capacity of athletes was expressed by higher values of at anaerobic threshold and peak conditions (P

  9. Changes in heart rate variability (HRV) in field hockey players during the 2006 World Cup

    OpenAIRE

    Rodas Font, Gil; Yanguas Leyes, Javier; Pedret, Carles; Ramos Castro, Juan José; Capdevila, L.

    2011-01-01

    The aim of this study is to determine the changes in heart rate variability (HRV) in field hockey players during the course of a world championship. The Spanish national team took part in the study by making daily records of the R-R interval (Omegawave System) on the days when matches took place. The baseline heart rate (HR) and several parameters of HRV were measured. The evolution of the average values of the HR and the various parameters of HRV during the 7 matches was compared using a...

  10. Heart rate reduction for 36 months with ivabradine reduces left ventricular mass in cardiac allograft recipients: a long-term follow-up study

    Directory of Open Access Journals (Sweden)

    Doesch AO

    2013-11-01

    Full Text Available Andreas O Doesch,1 Susanne Mueller,1 Christian Erbel,1 Christian A Gleissner,1 Lutz Frankenstein,1 Stefan Hardt,1 Arjang Ruhparwar,2 Philipp Ehlermann,1 Thomas Dengler,3 Hugo A Katus1 1Department of Cardiology, 2Department of Cardiovascular Surgery, University of Heidelberg, Heidelberg, 3SLK Plattenwald Hospital, Bad Friedrichshall, Germany Background: Due to graft denervation, sinus tachycardia is a common problem after heart transplantation, underlining the importance of heart rate control without peripheral effects. However, long-term data regarding the effects of ivabradine, a novel If channel antagonist, are limited in patients after heart transplantation. Methods: In this follow-up analysis, the resting heart rate, left ventricular mass indexed to body surface area (LVMI, tolerability, and safety of ivabradine therapy were evaluated at baseline and after 36 months in 30 heart transplant recipients with symptomatic sinus tachycardia versus a matched control group. Results: During the study period, ivabradine medication was stopped in three patients (10% of total. Further analysis was based on 27 patients with 36 months of drug intake. The mean patient age was 53.3±11.3 years and mean time after heart transplantation was 5.0±4.8 years. After 36 months, the mean ivabradine dose was 12.0±3.4 mg/day. Resting heart rate was reduced from 91.0±10.7 beats per minute before initiation of ivabradine therapy (ie, baseline to 81.2±9.8 beats per minute at follow-up (P=0.0006. After 36 months of ivabradine therapy, a statistically significant reduction of LVMI was observed (104.3±22.7 g at baseline versus 93.4±18.4 g at follow-up, P=0.002. Hematologic, renal, and liver function parameters remained stable during ivabradine therapy. Except for a lower mycophenolate mofetil dose at follow-up (P=0.02, no statistically significant changes in immunosuppressive drug dosage or blood levels were detected. No phosphenes were observed during 36 months of ivabradine intake despite active inquiry. Conclusion: In line with previously published 12-month data, heart rate reduction with ivabradine remained effective and safe in chronic stable patients after heart transplantation, and also during 36-month long-term follow-up. Further, a significant reduction of LVMI was observed only during ivabradine therapy. Therefore, ivabradine may have a sustained long-term beneficial effect with regard to left ventricular remodeling in heart transplant patients. Keywords: heart transplantation, heart rate control, ivabradine, left ventricular mass

  11. The relationship between heart rate reserve and oxygen uptake reserve in heart failure patients on optimized and non-optimized beta-blocker therapy

    Scientific Electronic Library Online (English)

    Vitor Oliveira, Carvalho; Guilherme Veiga, Guimarães; Edimar Alcides, Bocchi.

    Full Text Available BACKGROUND: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentag [...] e of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exercise test. METHODS: A total of 27 sedentary heart failure patients (86% male, 50±12 years) on optimized beta-blocker therapy with a left ventricle ejection fraction of 33±8% and 35 sedentary non-optimized heart failure patients (75% male, 47±10 years) with a left ventricle ejection fraction of 30±10% underwent the treadmill cardiopulmonary exercise test (Naughton protocol). Resting and peak effort values of both the percentage of oxygen consumption reserve and percentage of heart rate reserve were, by definition, 0 and 100, respectively. RESULTS: The heart rate slope for the non-optimized group was derived from the points 0.949±0.088 (0 intercept) and 1.055±0.128 (1 intercept), p

  12. Assessment of image quality of 64-row Dual Source versus Single Source CT coronary angiography on heart rate: A phantom study

    International Nuclear Information System (INIS)

    Purpose: To assess the influence of temporal resolution on image quality of computed tomographic (CT) coronary angiography by comparing 64-row Dual Source CT (DSCT) and Single Source CT (SSCT) at different heart rates. Methods: An anthropomorphic moving heart phantom was scanned at rest, and at 50 beats per minute (bpm) up to 110 bpm, with intervals of 10 bpm. 3D volume rendered images and curved multi-planar reconstructions (MPRs) were acquired and image quality of the coronary arteries was rated on a 5-points scale (1 = poor image quality with many artefacts, 5 = excellent image quality) for each heart rate and each scanner by 3 observers. Paired sample t-test and Wilcoxon Signed Ranks test were used to assess clinically relevant differences between both modalities. Results: The mean image quality scores at 70, 100 and 110 bpm were significantly higher for DSCT compared to SSCT. The overall mean image quality scores for DSCT (4.2 ± 0.6) and SSCT (3.0 ± 1.1) also differed significantly (p < 0.001). Conclusion: These initial results show a clinically relevant overall higher image quality for DSCT compared to SSCT, especially at heart rates of 70, 100 and 110 bpm. With its comparatively high image quality and low radiation dose, DSCT appears to be the method of choice in CT coronary angiography at heart rates above 70 bpm.

  13. E-bra with nanosensors, smart electronics and smart phone communication network for heart rate monitoring

    Science.gov (United States)

    Varadan, Vijay K.; Kumar, Prashanth S.; Oh, Sechang; Mathur, Gyanesh N.; Rai, Pratyush; Kegley, Lauren

    2011-04-01

    Heart related ailments have been a major cause for deaths in both men and women in United States. Since 1985, more women than men have died due to cardiac or cardiovascular ailments for reasons that are not well understood as yet. Lack of a deterministic understanding of this phenomenon makes continuous real time monitoring of cardiovascular health the best approach for both early detection of pathophysiological changes and events indicative of chronic cardiovascular diseases in women. This approach requires sensor systems to be seamlessly mounted on day to day clothing for women. With this application in focus, this paper describes a e-bra platform for sensors towards heart rate monitoring. The sensors, nanomaterial or textile based dry electrodes, capture the heart activity signals in form Electrocardiograph (ECG) and relay it to a compact textile mountable amplifier-wireless transmitter module for relay to a smart phone. The ECG signal, acquired on the smart phone, can be transmitted to the cyber space for post processing. As an example, the paper discusses the heart rate estimation and heart rate variability. The data flow from sensor to smart phone to server (cyber infrastructure) has been discussed. The cyber infrastructure based signal post processing offers an opportunity for automated emergency response that can be initiated from the server or the smartphone itself. Detailed protocols for both the scenarios have been presented and their relevance to the present emergency healthcare response system has been discussed.

  14. Diabetic retinopathy is associated with early autonomic dysfunction assessed by exercise-related heart rate changes

    Scientific Electronic Library Online (English)

    C.K., Kramer; C.B., Leitão; M.J., Azevedo; F.B., Valiatti; T.C., Rodrigues; L.H., Canani; J.L., Gross.

    1110-11-01

    Full Text Available Diabetic retinopathy has been associated with cardiac autonomic dysfunction in both type 1 and type 2 diabetes mellitus (DM) patients. Heart rate (HR) changes during exercise testing indicate early alterations in autonomous tonus. The aim of the present study was to investigate the association of di [...] abetic retinopathy with exercise-related HR changes. A cross-sectional study was performed on 72 type 2 and 40 type 1 DM patients. Autonomic dysfunction was assessed by exercise-related HR changes (Bruce protocol). The maximum HR increase, defined as the difference between the peak exercise rate and the resting rate at baseline, and HR recovery, defined as the reduction in HR from the peak exercise to the HR at 1, 2, and 4 min after the cessation of the exercise, were determined. In type 2 DM patients, lower maximum HR increase (OR = 1.62, 95%CI = 1.03-2.54; P = 0.036), lower HR recovery at 2 (OR = 2.04, 95%CI = 1.16-3.57; P = 0.012) and 4 min (OR = 2.67, 95%CI = 1.37-5.20; P = 0.004) were associated with diabetic retinopathy, adjusted for confounding factors. In type 1 DM, the absence of an increase in HR at intervals of 10 bpm each during exercise added 100% to the odds for diabetic retinopathy (OR = 2.01, 95%CI = 1.1-3.69; P = 0.02) when adjusted for DM duration, A1c test and diastolic blood pressure. In conclusion, early autonomic dysfunction was associated with diabetic retinopathy. The recognition of HR changes during exercise can be used to identify a high-risk group for diabetic retinopathy.

  15. Spectral analysis of heart rate fluctuations and optimum thermal management for low birth weight infants.

    Science.gov (United States)

    Davidson, S; Reina, N; Shefi, O; Hai-Tov, U; Akselrod, S

    1997-11-01

    Spectral analysis of heart rate variability is studied in 10 healthy growing premature infants to investigate the changes in autonomic balance achieved as a function of changes in skin temperature. Heart rate is obtained from ECG recordings and the power spectrum of beat-to-beat heart rate fluctuations is computed. The infants maintain mean rectal temperature within 36.3-37.2 degrees C, while skin temperature changes. The respiratory rate does not change at the different servocontrol set points. Heart rate is found to increase slightly, but consistently. The low-frequency band (0.02-0.2 Hz), reflecting the interplay of the sympathetic and parasympathetic tone and known to be maximum at the thermoneutral zone, is maximum at 35.5 and 36 degrees C and decreases gradually to a lower level at a servocontrol temperature of 36.5-37 degrees C. The high-frequency band (0.2-2.0 Hz), coinciding with the respiratory peak and reflecting parasympathetic activity, is significantly elevated at 36 degrees C (p balance and possibly reflecting the most comfortable conditions, occurs at 36 degrees C, although the differences are not statistically significant. Servocontrol skin temperature may thus be adapted, and possibly selected at 36 degrees C for growing premature infants in an attempt to achieve thermal comfort and more balanced autonomic activity. PMID:9538537

  16. Effects of Swedish massage therapy on blood pressure, heart rate, and inflammatory markers in hypertensive women.

    Science.gov (United States)

    Supa'at, Izreen; Zakaria, Zaiton; Maskon, Oteh; Aminuddin, Amilia; Nordin, Nor Anita Megat Mohd

    2013-01-01

    Swedish Massage Therapy (SMT) is known for its therapeutic relaxation effects. Hypertension is associated with stress and elevated endothelial inflammatory markers. This randomized control trial measured the effects of whole body SMT (massage group) or resting (control group) an hour weekly for four weeks on hypertensive women. Blood pressure (BP) and heart rate (HR) were measured before and after each intervention and endothelial inflammatory markers: vascular endothelial adhesion molecules 1 (VCAM-1) and intracellular adhesion molecules 1 (ICAM-1) were measured at baseline and after the last intervention. Massage group (n=8) showed significant systolic BP (SBP) reduction of 12?mmHg (P=0.01) and diastolic BP (DBP) reduction of 5?mmHg (P=0.01) after four sessions with no significant difference between groups. Reductions in HR were also seen in massage group after sessions 1, 3, and 4 with significant difference between groups. VCAM-1 showed significant reduction after four sessions: the massage group showed reduction of 998.05?ng/mL (P=0.03) and the control group of 375.70?ng/mL (P=0.01) with no significant differences between groups. There were no changes in ICAM-1. In conclusion, SMT or resting an hour weekly has effects on reducing BP, HR, and VCAM-1 in hypertensive women. PMID:24023571

  17. Heart rate variability in neurorehabilitation patients with severe acquired brain injury

    DEFF Research Database (Denmark)

    Vistisen, Simon Tilma; Hansen, Troels Krarup

    2014-01-01

    INTRODUCTION: Acquired brain injury (ABI) cause neural deficits. In addition to motor and cognitive deficits, the autonomic nervous system may be affected. This has been shown for neurorehabilitation patients with traumatic brain injury (TBI) by means of reduced heart rate variability (HRV). It was hypothesized that patient groups with other ABI aetiology (mainly stroke, subarachnoid haemorrhage and anoxia) would also present reduced HRV. METHODS: Patients consecutively admitted and severely ABI injured were considered for HRV measurements. HRV was extracted as a mean of four 5-minute ECG recordings at 6?pm, 10?pm, 2?am and 6?am the following day (scheduled resting periods). One 5-minute HRV recording from a sex- and age-matched group of healthy volunteers constituted control data. Standard deviation of normal-to-normal intervals (SDNN) and low frequency (LF) were primary HRV variables. RESULTS: Of 71 admitted patients, HRV was extracted from 49 patients. Patient SDNN and LF were reduced compared to controls (SDNN: 13?ms (CI?=?[10.8; 15.3]) vs 40.3?ms (CI?=?[36.6; 44.2]), p?CONCLUSION: It was found that HRV was considerably reduced in an heterogenic ABI patient group admitted for neurorehabilitation.

  18. Heart rate variability and treatment outcome in major depression: a pilot study.

    Science.gov (United States)

    Jain, Felipe A; Cook, Ian A; Leuchter, Andrew F; Hunter, Aimee M; Davydov, Dmitry M; Ottaviani, Cristina; Tartter, Molly; Crump, Caroline; Shapiro, David

    2014-08-01

    Variations in heart rate variability (HRV) have been associated with major depressive disorder (MDD), but the relationship of baseline HRV to treatment outcome in MDD is unclear. We conducted a pilot study to examine associations between resting baseline HRV and MDD treatment outcome. We retrospectively tested several parameters of HRV in an MDD treatment study with escitalopram (ESC, N=26) to generate a model of how baseline HRV related to treatment outcome, and cross-validated the model in a separate trial of MDD treatment with Iyengar yoga (IY, N=16). Lower relative power of very low frequency (rVLF) HRV at baseline predicted improvement in depressive symptoms when adjusted for age and gender (R2>.43 and pgender. In conclusion, baseline resting rVLF was associated with depression treatment outcome in two independent MDD treatment studies. These results should be interpreted with caution due to limited sample size, but a strength of this study is its validation of the rVLF predictor in an independent sample. rVLF merits prospective confirmation as a candidate biomarker. PMID:24769434

  19. Explaining the recent decrease in coronary heart disease mortality rates in Ireland, 1985–2000

    Science.gov (United States)

    Bennett, Kathleen; Kabir, Zubair; Unal, Belgin; Shelley, Emer; Critchley, Julia; Perry, Ivan; Feely, John; Capewell, Simon

    2006-01-01

    Study objectives To examine the proportion of the recent decline in coronary heart disease (CHD) deaths in Ireland attributable to (a) “evidence based” medical and surgical treatments, and (b) changes in major cardiovascular risk factors. Design setting IMPACT, a previously validated model, was used to combine and analyse data on the use and effectiveness of specific cardiology treatments and risk factor trends, stratified by age and sex. The main data sources were published trials and meta?analyses, official statistics, clinical audits, and observational studies. Results Between 1985 and 2000, CHD mortality rates in Ireland fell by 47% in those aged 25–84. Some 43.6% of the observed decrease in mortality was attributed to treatment effects and 48.1% to favourable population risk factor trends; specifically declining smoking prevalence (25.6%), mean cholesterol concentrations (30.2%), and blood pressure levels (6.0%), but offset by increases in adverse population trends related to obesity, diabetes, and inactivity (?13.8%). Conclusions The results emphasise the importance of a comprehensive strategy that maximises population coverage of effective treatments, and that actively promotes primary prevention, particularly tobacco control and a cardioprotective diet. PMID:16537349

  20. Heart rate is associated with markers of fatty acid desaturation: the GOCADAN study

    Directory of Open Access Journals (Sweden)

    Sven O.E. Ebbesson

    2012-03-01

    Full Text Available Objectives: To determine if heart rate (HR is associated with desaturation indexes as HR is associated with arrhythmia and sudden death. Study design: A community based cross-sectional study of 1214 Alaskan Inuit. Methods: Data of FA concentrations from plasma and red blood cell membranes from those ?35 years of age (n =?819 were compared to basal HR at the time of examination. Multiple linear regression with backward stepwise selection was employed to analyze the effect of the desaturase indexes on HR, after adjustment for relevant covariates. Results: The ?5 desaturase index (?5-DI measured in serum has recently been associated with a protective role for cardiovascular disease. This index measured here in plasma and red blood cells showed a negative correlation with HR. The plasma stearoyl-CoA-desaturase (SCD index, previously determined to be related to cardiovascular disease (CVD mortality, on the other hand, was positively associated with HR, while the ?6 desaturase index (?6-DI had no significant effect on HR. Conclusion: Endogenous FA desaturation is associated with HR and thereby, in the case of SCD, possibly with arrhythmia and sudden death, which would at least partially explain the previously observed association between cardiovascular mortality and desaturase activity.

  1. A Body Shape Index and Heart Rate Variability in Healthy Indians with Low Body Mass Index

    Science.gov (United States)

    Thomas, Tinku; Bharathi, Ankalmadagu Venkatsubbareddy; Sucharita, Sambashivaiah

    2014-01-01

    Background. One third of Indian population is said to be suffering from chronic energy deficiency (CED), with increased risk of developing chronic diseases. A new anthropometric measure called A Body Shape Index (ABSI) is said to be a better index in predicting risks for premature mortality. ABSI is also in part said to be a surrogate of visceral fat. Objective. The present study aimed to explore the association between indices of HRV (heart rate variability), BMI, WC, and ABSI in healthy Indian males with low BMI (BMI < 18.5?kg/m2) and to compare with normal BMI group (BMI 18.5 to 24.9?kg/m2). Methodology. ABSI and BMI were derived from anthropometric parameters, namely, height, weight, and waist circumference in 178 males aged 18 to 78 years. Subjects were categorized into two groups based on their BMI. Results and Conclusions. Power spectral analysis of HRV demonstrated a significant negative correlation between Log HF (high frequency) and ABSI in both low BMI [?24.2 (9.4), P < 0.05] and normal BMI group [?23.41 (10.1), P < 0.05] even after controlling for age. Thus even with slight increase in BMI among low BMI individuals, there could be a greater risk of cardiovascular morbidity and mortality. PMID:25371818

  2. Determination of anaerobic threshold through heart rate and near infrared spectroscopy in elderly healthy men

    Scientific Electronic Library Online (English)

    Michel S., Reis; Danilo C., Berton; Ross, Arena; Aparecida M., Catai; Jose A., Neder; Audrey, Borghi-Silva.

    2013-10-01

    Full Text Available BACKGROUND: Aging leads to low functional capacity and this can be reversed by safe and adequate exercise prescription. OBJECTIVE: The aim of this study was to identify the anaerobic threshold (AT) obtained from the V-slope method as well as visual inspection of oxyhemoglobin ( O2Hb) and deox [...] yhemoglobin (HHb) curves and compare findings with the heteroscedastic (HS) method applied to carbon dioxide production ( CO2), heart rate (HR), and HHb data in healthy elderly men. A secondary aim was to assess the degree of agreement between methods for AT determination. METHOD: Fourteen healthy men (61.4±6.3 years) underwent cardiopulmonary exercise testing (CPX) on a cycle ergometer until physical exhaustion. Biological signals collected during CPX included: ventilatory and metabolic variables; spectroscopy quasi-infrared rays - NIRS; and HR through a cardio-frequency meter. RESULTS: We observed temporal equivalence and similar values of power (W), absolute oxygen consumption (O2 - mL/min), relative O2 ( mL.Kg - 1.min -1), and HR at AT by the detection methods performed. In addition, by the Bland-Altman plot, HR confirmed good agreement between the methods with biases between -1.3 and 3.5 beats per minute. CONCLUSIONS: (i) all detection methods were sensitive in identifying AT, including the HS applied to HR and (ii) the methods showed a good correlation in the identification of AT. Thus, these results support HR as valid and readily available parameter in determining AT in healthy elderly men.

  3. Meditation-induced changes in high-frequency heart rate variability predict smoking outcomes

    Directory of Open Access Journals (Sweden)

    JudsonA.Brewer

    2012-03-01

    Full Text Available Background: High-frequency heart rate variability (HF-HRV is a measure of parasympathetic nervous system output that has been associated with enhanced self-regulation. Low resting levels of HF-HRV are associated with nicotine dependence and blunted stress-related changes in HF-HRV are associated with decreased ability to resist smoking. Meditation has been shown to increase HF-HRV. However, it is unknown whether tonic levels of HF-HRV or acute changes in HF-HRV during meditation predict treatment responses in addictive behaviors such as smoking cessation. Purpose: To investigate the relationship between HF-HRV and subsequent smoking outcomes. Methods: HF-HRV during resting baseline and during mindfulness meditation was measured within two weeks of completing a 4-week smoking cessation intervention in a sample of 31 community participants. Self-report measures of smoking were obtained at a follow up 17-weeks after the initiation of treatment. Results: Regression analyses indicated that individuals exhibiting acute increases in HF-HRV from resting baseline to meditation smoked fewer cigarettes at follow-up than those who exhibited acute decreases in HF-HRV (b=-4.94, p=.009. Conclusion: Acute changes in HF-HRV in response to meditation may be a useful tool to predict smoking cessation treatment response.

  4. Association of High Blood Pressure with Reduced Heart Rate Variability during Childhood

    Directory of Open Access Journals (Sweden)

    Gui-Ling Xie

    2013-02-01

    Full Text Available Objective: To determine the association between heart rate variability (HRV and hypertension in Chinese children.Methods: The study was conducted in First Hospital of Jilin University, China. A total of 101 children were recruited in this study. They were divided into a high systolic blood pressure (SBP group (HS group and normal SBP group (NS group according to the SBP levels. In the second set of experiments, the children were divided into a high diastolic blood pressure (DBP group (HD group and normal DBP group (ND group according to the DBP levels. HRV measurements were performed, and the time domain and power spectrum values were calculated.Findings: The differences of low frequency (LF/high frequency (HF ratio, HF, and standard deviation of normal-to-normal RR intervals (SDNN between daytime and nighttime were obviously abolished in HS and HD groups. The HS group displayed significantly lower values of HRV over a 24 h period compared to the NS group (SDNN, standard deviation of the averaged normal-to-normal RR intervals [SDANN], Triangle Index, root mean square successive difference [RMSSD], total power [TP], ultra-LF [ULF], and HF. Only the Triangle Index in the HD group was lower than that in ND group.Conclusion: We provide evidence that HRV is reduced and the circadian rhythm of HRV is weakened in hypertensive children, and hypothesize that a reduced HRV is a potential pathophysiological mechanism linking childhood hypertension and adulthood cardiovascular diseases.

  5. Effects of radiation emitted from mobile phones on short- term heart rate variability parameters

    Directory of Open Access Journals (Sweden)

    Derya Y?lmaz

    2012-08-01

    Full Text Available Objective: In this study, the effects of radiation emitted from mobile phone (MP on heart rate variability (HRV which is accepted a non-invasive indicator of autonomic nervous system (ANS were investigated with considering the deficiency of previous studies. Methods: A randomized controlled study has been designed and utilized with 30 young and healthy volunteers. During the experiment that had three periods, the electrocardiogram (ECG and respiration signals were recorded and MP was attached to subjects’ right ear with a bone. Ten subjects selected randomly were exposed to high -level radiation during the second period (Experimental Group 1. Ten of others were exposed during the third period with maximum level radiation (Experimental Group 2. Ten records were also made while MP was closed as a control. Short -term HRV parameters were obtained and repeated measures ANOVA and suitable post-hoc tests applied to the results. Results: According to the results of the repeated measures ANOVA; there were no significant main effects of groups. However, there were some significant differences in measuring time periods and groups*period interactions. The post-hoc tests showed that mean R to R interval and HF power are significantly changed by maximum radiation emitted from MP. Conclusion: Due to the radiation emitted from MPs at maximum power, some changes may occur in HRV parameters that are associated with increased parasympathetic activity. But, the level of these changes is similar to daily activities as excitement, and stand up.

  6. Development and preliminary evaluation of an Android based heart rate variability biofeedback system.

    Science.gov (United States)

    Abtahi, F; Berndtsson, A; Abtahi, S; Seoane, F; Lindecrantz, K

    2014-01-01

    The reduced Heart Rate Variability (HRV) is believed to be associated with several diseases such as congestive heart failure, diabetes and chronic kidney diseases (CKD). In these cases, HRV biofeedback may be a potential intervention method to increase HRV which in turn is beneficial to these patients. In this work, a real-time Android biofeedback application based on a Bluetooth enabled ECG and thoracic electrical bioimpedance (respiration) measurement device has been developed. The system performance and usability have been evaluated in a brief study with eight healthy volunteers. The result demonstrates real-time performance of system and positive effects of biofeedback training session by increased HRV and reduced heart rate. Further development of the application and training protocol is ongoing to investigate duration of training session to find an optimum length and interval of biofeedback sessions to use in potential interventions. PMID:25570716

  7. Incident solar radiation and coronary heart disease mortality rates in Europe

    International Nuclear Information System (INIS)

    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 D3 could be the critical missing confounder in the analysis of the beneficial health outcome of the Mediterranean diet

  8. Resting heart rate is a predictor of mortality in chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Jensen, Magnus Thorsten; Marott, Jacob L

    2012-01-01

    The clinical significance of high heart rate in COPD is unexplored.We investigated the association between resting heart rate (RHR), pulmonary function, and prognosis in subjects with COPD.16,696 subjects above 40 years from The Copenhagen City Heart Study, a prospective study of the general population, followed for 35.3 years, 10,986 deaths occurring. Analyses were performed using time-dependent Cox-models and net reclassification index (NRI).RHR increased with severity of COPD (p85 bpm was 5.5 years in no COPD, 9.8 years in mild, 6.7 years in moderate, and 5.9 years in severe/very severe, (p

  9. Nocturnal variations in peripheral blood flow, systemic blood pressure, and heart rate in humans

    DEFF Research Database (Denmark)

    Sindrup, J H; Kastrup, J

    1991-01-01

    Subcutaneous adipose tissue blood flow rate, together with systemic arterial blood pressure and heart rate under ambulatory conditions, was measured in the lower legs of 15 normal human subjects for 12-20 h. The 133Xe-washout technique, portable CdTe(Cl) detectors, and a portable data storage unit were used for measurement of blood flow rates. An automatic portable blood pressure recorder and processor unit was used for measurement of systolic blood pressure, diastolic blood pressure, and heart rate every 15 min. The change from upright to supine position at the beginning of the night period was associated with a 30-40% increase in blood flow rate and a highly significant decrease in mean arterial blood pressure and heart rate (P less than 0.001 for all). Approximately 100 min after the subjects went to sleep an additional blood flow rate increment (mean 56%) and a simultaneous significant decrease in mean arterial blood pressure (P less than 0.001) were observed. The duration of this hyperemic phase was 116 min. A highly significant reduction of the subcutaneous vascular resistance (50%) was demonstrated during the hyperemic blood flow rate phase compared with the surrounding phases (P less than 0.0001). The synchronism of the nocturnal subcutaneous hyperemia and the decrease in systemic mean arterial blood pressure point to a common, possibly central nervous or humoral, eliciting mechanism.

  10. Correlation between Mortality of Prehospital Trauma Patients and Their Heart Rate Complexity

    Directory of Open Access Journals (Sweden)

    Pegah ShojaMozafar

    2012-12-01

    Full Text Available Recently, nonlinear analysis of R-to-R interval (RRI in heart rate has brought research attention in medicine to improve predictive accuracy of medication in severely injured patients. It seems conventional vital signs information such as heart rate and blood pressure to identify critically injured patients eventually replaced by heartrate complexity (HRC analysis to the electrocardiogram (ECG of patients in trauma centers. In this respect, different nonlinear analysis tools such as; power spectra, entropy, fractal dimension, auto-correlation function and auto-correlation have been adapted for this complexity analysis of ECG signal. Reidbord and Redington [1] were one of the early reports on applications of nonlinear analysis of the heart physiology. Moody and his colleagues could confidently predicted survival in heart failure cases by use of fully automated methods for deriving nonlinear and conventional indices of heart rate dynamics [2]. Further studies were reported in cases of arrhythmia or general anesthesia by Pomfrett [3], Fortrat [4], Lass [5] and references therein. Recently, noteworthy works of Batchinsky and coworkers have shown that prehospital loss of RRI complexity is associated with mortality in trauma patients [6-8]. They have also shown that prediction of trauma survival by analysis of heart rate complexity is even possible by reducing data set size from 800-beat to 200 or lower beat data sets. In this article, we will use different data nonlinear analysis tools such as; power spectrum, entropy, Lyapunov exponent, capacity dimension and correlation function to analyze HRC as a sensitive indictor of physiologic deterioration. In these analyses, we will use real data of 270-beat sections of ECG from 45 emergency patients brought to Shiraz Rejaee Hospetal trauma center prior to any medication. As we can see, using some manipulation on raw data will provide more informative vital signs in our nonlinear analyses.

  11. Heart rate control with adrenergic blockade: Clinical outcomes in cardiovascular medicine

    Directory of Open Access Journals (Sweden)

    David Feldman

    2010-05-01

    Full Text Available David Feldman1, Terry S Elton2, Doron M Menachemi3, Randy K Wexler41Heart Failure/Transplant and VAD Programs, Minneapolis Heart Institute, Minneapolis, Minnesota, USA; 2Division of Pharmacology, College of Pharmacology, The Ohio State University, Columbus, Ohio, USA; 3Heart Failure Services, Edith Wolfson Medical Center, The Heart Institute, Sakler School of Medicine, Tel-Aviv University, Holon, Israel; 4Department of Clinical Family Medicine, The Ohio State University, Columbus, Ohio, USAAbstract: The sympathetic nervous system is involved in regulating various cardiovascular parameters including heart rate (HR and HR variability. Aberrant sympathetic nervous system expression may result in elevated HR or decreased HR variability, and both are independent risk factors for development of cardiovascular disease, including heart failure, myocardial infarction, and hypertension. Epidemiologic studies have established that impaired HR control is linked to increased cardiovascular morbidity and mortality. One successful way of decreasing HR and cardiovascular mortality has been by utilizing ?-blockers, because their ability to alter cell signaling at the receptor level has been shown to mitigate the pathogenic effects of sympathetic nervous system hyperactivation. Numerous clinical studies have demonstrated that ?-blocker-mediated HR control improvements are associated with decreased mortality in postinfarct and heart failure patients. Although improved HR control benefits have yet to be established in hypertension, both traditional and vasodilating ?-blockers exert positive HR control effects in this patient population. However, differences exist between traditional and vasodilating ?-blockers; the latter reduce peripheral vascular resistance and exert neutral or positive effects on important metabolic parameters. Clinical evidence suggests that attainment of HR control is an important treatment objective for patients with cardiovascular conditions, and vasodilating ?-blocker efficacy may aid in accomplishing improved outcomes.Keywords: adrenergic beta-antagonists, heart failure, hypertension, myocardial infarction

  12. Coupling Between Blood Pressure And Heart Rate as Markers of Sudden Cardiac Death.

    Czech Academy of Sciences Publication Activity Database

    Halámek, Josef; Jurák, Pavel; Kára, T.; Nykodým, J.; Eisenberger, M.; Sou?ek, M.

    Brno : Brno University of Technology, 2004, s. 352-354. ISBN 80-214-2633-0. ISSN 1211-412X. [Biosignal 2004 /17./. Brno (CZ), 23.06.2004-25.06.2004] R&D Projects: GA ?R GA102/02/1339 Keywords : heart rate * systolic blood pressure * cardioverterdefibrilator Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  13. Facial electromyogram and heart-rate correlates of a paradoxical attitude change to antinuclear war information

    Energy Technology Data Exchange (ETDEWEB)

    Vigne, J.J.; Dale, J.A.; Klions, H.L.

    1988-12-01

    The effects of film images versus film descriptions of the effects of nuclear explosions (versus a no-film control) on corrugator muscle tension, heart rate, attitude and mood were investigated. The last 5 min. of the images were associated with more corrugator tension for that condition when compared to the last 5 min. of the description condition. The groups did not differ in heart rate but women in both groups showed an increase in heart rate whereas men in both groups showed a decrease in heart rate. Film groups did not differ in their significant increases in anxiety, hostility, and depression on the Multiple Adjective Affect Checklist. On the pretest there was no significant correlation between scores on Betts' Questionnaire Upon Mental Imagery and scores on Goldenring and Doctor's index of concern for nuclear war. The vivid-image film group showed a decrease in concern for nuclear war when compared to the descriptive film group and the no-film control.

  14. Atypical Pupillary Light Reflex and Heart Rate Variability in Children with Autism Spectrum Disorder

    Science.gov (United States)

    Daluwatte, Chathuri; Miles, Judith H.; Christ, Shawn E.; Beversdorf, David Q.; Takahashi, T. Nicole; Yao, Gang

    2013-01-01

    We investigated pupillary light reflex (PLR) in 152 children with ASD, 116 typically developing (TD) children, and 36 children with non-ASD neurodevelopmental disorders (NDDs). Heart rate variability (HRV) was measured simultaneously to study potential impairments in the autonomic nervous system (ANS) associated with ASD. The results showed that…

  15. Influences of textured substrates on the heart rate of developing zebrafish embryos

    International Nuclear Information System (INIS)

    Identification of the effects of different textured substrates on zebrafish (Danio rerio) embryos provides insights into the influence of external stimuli on normal cardiovascular functions in the developmental stages of the embryos. This knowledge can be used in numerous genetic studies using zebrafish as an animal model as well as in bioanalytical assays using digital microfluidics. In this study, zebrafish embryos were systematically positioned and in vivo imaged on four types of silicon substrates. These substrates exhibited surface textures and surface wettability that were well modulated by wet chemical etching. The heart rate of the developing embryos significantly increased by 9.1% upon exposure to textured Si substrates with nanostructured surfaces compared with bare Si substrates. Modulation of surface wettability in the tested substrates also responded to the increase in the heart rate of the embryo; however, the effect of surface wettability on heart rate was slight compared with the effect of texture. In-depth experimental and statistical investigations of heart rate under the effects of substrate textures imply a pathway through which the inner mass of the embryo reacts to external stimuli. These findings contribute to zebrafish-related studies and suggest other factors to consider in the design of nanostructure-based microfluidics and other biomedical devices. (paper)

  16. Heart Rate Variability – a Tool to Differentiate Positive and Negative Affective States in Pigs?

    Science.gov (United States)

    The causal neurophysiological processes, such as autonomic nervous system activity, that mediate behavioral and physiological reactivity to an environment have largely been ignored. Heart rate variability (HRV) analysis is a clinical diagnostic tool used to assess affective states (stressful and ple...

  17. Complexity of everyday life heart rate dynamics and attentional control in healthy students.

    Science.gov (United States)

    Bornas, Xavier; Llabrés, Jordi; Morillas-Romero, Alfonso; Aguayo-Siquier, Blanca; Balle, Maria; Tortella-Feliu, Miquel

    2013-07-01

    Effective regulation of emotions requires the ability to voluntarily manage attention, i.e. attentional control (AC), which has been related to heart rate variability and vagal tone in laboratory based research. In this study, we calculated the correlation dimension (CD), the fractal-like properties (scaling exponents ?1 and ?2, and fractal dimension) and the sample entropy of heart rate time series obtained from ECG recordings (4 hours long each) taken from a sample of healthy students (n=47) during everyday activities. AC was assessed through a self-reported questionnaire. As expected, a linear positive correlation was found between AC scores and CD and entropy, but no associations were found between AC and ?1 and fractal dimension. The association between AC and ?2 was negative and marginally significant. No associations were found between AC and linear heart rate variability measures. These results show that nonlinear measures of long, everyday life, heart rate time series may provide useful information about the AC ability of healthy students. PMID:23735491

  18. Heart rate variability and particulate exposure in vehicle maintenance workers: a pilot study.

    Science.gov (United States)

    Eninger, Robert M; Rosenthal, Frank S

    2004-08-01

    The association between occupational exposure to PM(2.5) and heart rate variability was investigated in a repeated measures, longitudinal study of vehicle maintenance workers occupationally exposed to automobile emissions. Five subjects were monitored for occupational exposure to fine particulate matter (PM(2.5)) on 6 workdays using an aerosol photometer, validated with side-by-side sampling with a gravimetric method. End-of-day heart rate variability statistics were derived using short-term electrocardiogram recordings for each participant. Workplace carbon monoxide and outdoor, ambient fine particulate matter were also monitored. Regression statistics were used to investigate associations between same-day PM(2.5) levels and heart rate variability statistics using mixed-effects multiple regression of pooled data. No statistically significant associations were observed between occupational PM(2.5) and measures of heart rate variability. A statistically significant increase in total spectral power was associated with ambient PM(2.5) (p < 0.05). The data suggest a threshold below which no degradation in cardiac autonomic control of healthy workers occurs when challenged by occupational PM(2.5) exposure. This study was limited in population, exposure level, and type of particulate exposures. Additional studies are recommended on broader occupational populations. PMID:15238301

  19. Episodic arterial oxygen desaturation and heart rate variations following major abdominal surgery.

    DEFF Research Database (Denmark)

    Rosenberg, J; Dirkes, W E

    1989-01-01

    In 20 patients undergoing elective major abdominal surgery, heart rate and arterial oxygen saturation were monitored continuously during the night 2 days before operation and during the first and second nights after operation (23:00 to 07:30). Mean heart rate increased by 16 beat min-1 (P less than 0.0006) and mean oxygen saturation decreased by 3.2% (P less than 0.0002) after operation. Four patients had 21, 27, 120 and 372 episodes of sudden desaturation to a value less than 80% on the second night after operation. The patient with 372 episodes of sudden desaturation had severe cardiac arrhythmias on the morning of the third day after operation. In another patient the episodes of desaturation correlated with increases in heart rate. There was no correlation between administration of opioids and heart rate and saturation disturbances. The mechanism and clinical relevance of episodic desaturation in the late postoperative period remain unknown, but may be important in the pathogenesis of post-operative cardiac, cerebral and wound dysfunction.

  20. Metabolic Syndrome and Short-Term Heart Rate Variability in Adults with Intellectual Disabilities

    Science.gov (United States)

    Chang, Yaw-Wen; Lin, Jin-Ding; Chen, Wei-Liang; Yen, Chia-Feng; Loh, Ching-Hui; Fang, Wen-Hui; Wu, Li-Wei

    2012-01-01

    Metabolic syndrome (MetS) increases the risk of cardiovascular events. Heart rate variability (HRV) represents autonomic functioning, and reduced HRV significantly increases cardiovascular mortality. The aims of the present paper are to assess the prevalence of MetS in adults with intellectual disabilities (ID), the difference in short-term HRV…

  1. 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…

  2. Hierarchical Structure in Healthy and Diseased Heart Rate Variability in Humans

    CERN Document Server

    Ching, E S C; Zhang, C; Ching, Emily S.C.

    2003-01-01

    It is shown that the heart rate variability (HRV) in healthy and diseased humans possesses a hierarchical structure of the She-Leveque (SL) form. This structure, first found in measurements in turbulent fluid flows, implies further details in the HRV multifractal scaling. The potential of diagnosis is also discussed based on the characteristics derived from the SL hierarchy.

  3. Heart rate and energy expenditure during garbage collection in Rio de Janeiro, Brazil.

    Science.gov (United States)

    Anjos, Luiz A; Ferreira, João A; Damião, Jorginete J

    2007-11-01

    Physiological workload is used to estimate the physical demand of tasks in the workforce, but limited information is available for the various work activities in developing countries. Eighty-three randomly selected male workers participated in the present study, aimed at assessing the physiological workload of garbage collection (GC) in Rio de Janeiro, Brazil. Heart rate (HR) was obtained on four consecutive workdays. Energy expenditure (EE) was extrapolated from heart rate data based on individual laboratory-established heart rate/oxygen consumption curve in 70 workers. Mean HR during GC was 104.0 +/- 11.7 bpm (+/- SD), representing 56.9 +/- 7.5% of maximum heart rate. EE was 1608.3 +/- 738.5 kcal for an average of 293.1 +/- 103.9 minutes of work per day. Based on all measurements, work in garbage collection in Rio de Janeiro can be considered excessively heavy. These data emphasize the need to develop appropriate classification of workload to be used in health-related research and in the development of maximum acceptable work time in association with the physiological workload, particularly in developing countries. PMID:17952267

  4. Defining asymmetry in heart rate variability signals using a Poincaré plot

    International Nuclear Information System (INIS)

    The asymmetry in heart rate variability is a visibly obvious phenomenon in the Poincaré plot of normal sinus rhythm. It shows the unevenness in the distribution of points above and below the line of identity, which indicates instantaneous changes in the beat to beat heart rate. The major limitation of the existing asymmetry definition is that it considers only the instantaneous changes in the beat to beat heart rate rather than the pattern (increase/decrease). In this paper, a novel definition of asymmetry is proposed considering the geometry of a 2D Poincaré plot. Based on the proposed definition, traditional asymmetry indices—Guzik's index (GI), Porta's index (PI) and Ehlers' index (EI)—have been redefined. In order to compare the effectiveness of the new definition, all indices have been calculated for RR interval series of 54 subjects with normal sinus rhythm of 5 min and 30 min duration. The new definition resulted in a higher prevalence of normal subjects showing asymmetry in heart rate variability

  5. Increased resting heart rate with pollutants in a population based study

    OpenAIRE

    Ruidavets, J.; Cassadou, S.; Cournot, M.; Bataille, V.; Meybeck, M.; Ferrieres, J.

    2005-01-01

    Background: Air pollution is associated with cardiovascular mortality. Changes in the autonomic nervous system may contribute to cardiac arrhythmias and cardiovascular mortality. This study investigated the relations between air pollutant concentrations of sulphur dioxide (SO2), ozone (O3), nitric dioxide (NO2), and resting heart rate (RHR) in a population based study.

  6. Evaluating the Prediction of Maximal Heart Rate in Children and Adolescents

    Science.gov (United States)

    Mahon, Anthony D.; Marjerrison, Andrea D.; Lee, Jonah D.; Woodruff, Megan E.; Hanna, Lauren E.

    2010-01-01

    In this study, we compared measured maximal heart rate (HRmax) to two different HRmax prediction equations [220-age and 208-0.7(age)] in 52 children ages 7-17 years. We determined the relationship of chronological age, maturational age, and resting HR to measured HRmax and assessed seated resting HR and HRmax during a graded exercise test.…

  7. The effects of digoxin and ?-methyldigoxin on the heart rate of decompensated patients with atrial fibrillation

    International Nuclear Information System (INIS)

    Eighteen patients with atrial fibrillation were given digoxin 0.13 mg twice daily for 3 weeks and ?-methyldigoxin 0.10 mg twice daily for another 3 weeks. At the end of each 3 week period an exercise test was performed and the effects on the heart rate of the two drugs were compared. No difference in heart rate was obtained at rest, wheareas the heart rate after 6 min of exercise was higher during treatment with digoxin (131 beats/min) than when the patients were taking ?-methyldigoxin (124 beats/min). There were no significant differences between digoxin and ?-methyldigoxin in their effects on the ECT (R-R intervals, T-wave, Q-T duration). The plasma concentrations of the two glycosides were determined by radioimmunoassay and by 86Rb-uptake inhibition assay. Comparable plasma concentration values (1.0 ng/ml for digoxin, 1.1 ng/ml for ?-methyldigoxin, mean values) were obtained by radioimmunoassay, but the 86Rb-technique gave significantly higher values (mean 1.5 ng/ml) for ?-methyldigoxin. It is concluded that ?-methyldigoxin is equal to digoxin for producing slowing of the heart rate in patients with atrial fibrillation. (orig.)

  8. Biosocial Bases of Reactive and Proactive Aggression: The Roles of Community Violence Exposure and Heart Rate

    Science.gov (United States)

    Scarpa, Angela; Tanaka, Akiho; Haden, Sara Chiara

    2008-01-01

    In order to more fully understand how individual differences influence adaptation to violence, this study examined the moderating influence of resting heart rate (HR) and HR variability (HRV) between community violence (CV) exposure and child reactive/proactive aggression. Forty 7-13-year-old community children self-reported CV exposure (i.e.,…

  9. Influences of textured substrates on the heart rate of developing zebrafish embryos

    Science.gov (United States)

    Chen, Chia-Yun; Chen, Chia-Yuan

    2013-07-01

    Identification of the effects of different textured substrates on zebrafish (Danio rerio) embryos provides insights into the influence of external stimuli on normal cardiovascular functions in the developmental stages of the embryos. This knowledge can be used in numerous genetic studies using zebrafish as an animal model as well as in bioanalytical assays using digital microfluidics. In this study, zebrafish embryos were systematically positioned and in vivo imaged on four types of silicon substrates. These substrates exhibited surface textures and surface wettability that were well modulated by wet chemical etching. The heart rate of the developing embryos significantly increased by 9.1% upon exposure to textured Si substrates with nanostructured surfaces compared with bare Si substrates. Modulation of surface wettability in the tested substrates also responded to the increase in the heart rate of the embryo; however, the effect of surface wettability on heart rate was slight compared with the effect of texture. In-depth experimental and statistical investigations of heart rate under the effects of substrate textures imply a pathway through which the inner mass of the embryo reacts to external stimuli. These findings contribute to zebrafish-related studies and suggest other factors to consider in the design of nanostructure-based microfluidics and other biomedical devices.

  10. Effects of bee venom acupuncture on heart rate variability, pulse wave, and cerebral blood flow for types of Sasang Constitution

    Directory of Open Access Journals (Sweden)

    Lee Sang-min

    2009-03-01

    Full Text Available 1. Objectives: To evaluate effects of bee venom acupuncture on cardiovascular system and differences according to each constitution. 2. Methods: Heart rate variability, pulse wave and the velocity of cerebral blood flow were measured before bee venom acupuncture(BVA, right after and after 30 minuets, had been applied to 20 subjects. 3. Results: 1. BVA did not have effects on measurement variables of heart rate variability. 2. BVA had effects on pulse wave, showing total time, radial augmentation index up and height of percussion wave, time to percussion wave, sum of pulse pressure down. 3. BVA did not have effects on the cerebral blood flow velocity when considering not Sasang Constitution 4. Considering Sasang Constitution, BVA demonstrates different responses in time to preincisura wave, mean blood flow velocity, peak systolic velocity and end diastolic velocity. 4.Conclusion: From those results, the following conclusions are obtained. Cause BVA alters pulse wave and makes differences in the cerebral blood flow velocity according to Sasang Constitution. Various methods of BVA treatment are needed considering Sasang Constitution.

  11. DISCREPANCY BETWEEN TRAINING, COMPETITION AND LABORATORY MEASURES OF MAXIMUM HEART RATE IN NCAA DIVISION 2 DISTANCE RUNNERS

    Directory of Open Access Journals (Sweden)

    Alvah C. Stahlnecker IV

    2008-12-01

    Full Text Available A percentage of either measured or predicted maximum heart rate is commonly used to prescribe and measure exercise intensity. However, maximum heart rate in athletes may be greater during competition or training than during laboratory exercise testing. Thus, the aim of the present investigation was to determine if endurance-trained runners train and compete at or above laboratory measures of 'maximum' heart rate. Maximum heart rates were measured utilising a treadmill graded exercise test (GXT in a laboratory setting using 10 female and 10 male National Collegiate Athletic Association (NCAA division 2 cross-country and distance event track athletes. Maximum training and competition heart rates were measured during a high-intensity interval training day (TR HR and during competition (COMP HR at an NCAA meet. TR HR (207 ± 5.0 b·min-1; means ± SEM and COMP HR (206 ± 4 b·min-1 were significantly (p < 0.05 higher than maximum heart rates obtained during the GXT (194 ± 2 b·min-1. The heart rate at the ventilatory threshold measured in the laboratory occurred at 83.3 ± 2.5% of the heart rate at VO2 max with no differences between the men and women. However, the heart rate at the ventilatory threshold measured in the laboratory was only 77% of the maximal COMP HR or TR HR. In order to optimize training-induced adaptation, training intensity for NCAA division 2 distance event runners should not be based on laboratory assessment of maximum heart rate, but instead on maximum heart rate obtained either during training or during competition

  12. [The effect of public defense of a doctoral thesis on the heart rate of the doctoral candidate].

    Science.gov (United States)

    Kiljander, Toni; Toikka, Jyri; Koskenvuo, Juha; Jaakkola, Ilkka

    2011-01-01

    The effect of public defense of a doctoral thesis on the heart rate of the doctoral candidate Most doctoral candidates find the public defense of a doctoral thesis an exciting and stressful experience. In this study, Holter recording during the defense was made for four doctoral candidates of the Faculty of Medicine. Maximum heart rate among the subjects was on the average 172 beats/min with a median heart rate of 116 beats/min. Sympathicotonia and release of stress hormones associated with the defense raise the heart rate to levels that may be very high for several hours. This is a risk factor for a coronary event and should be considered, if the doctoral candidate has coronary heart disease, carries risk factors for coronary heart disease, or is an elderly person. PMID:21805898

  13. A simple test of one minute heart rate variability during deep breathing for evaluation of sympathovagal imbalance in patients with type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Heart rate variability (HRV) refers to the magnitude of the fluctuation in the number of heart beats per minute in conjunction with respiration. HRV with deep breathing (HRVdb) has recently become a popular non-invasive research tool in cardiology. This study was carried out to determine and compare the HRV in patients with Type 2 DM with those of Non diabetic controls. Methods: Sixty diabetic patients attending out patient department in Karnataka Institute of Diabetology, Bangalore and 60 age-matched controls were enrolled. HRV was performed on all the subjects and the results obtained were compared between the groups. The One minute HRV was analysed during deep breathing and defined as the difference in beats/minute between the shortest and the longest heart rate interval measured by lead II electrocardiographic recording during six cycles of deep breathing. Results: Statistically significant decrease in mean minimal heart rate and 1 minute HRV (16.30 +- 6.42 vs 29.33 +- 8.39) was observed during deep breathing among Type 2 Diabetic patients on comparison with that of healthy controls. There was no significant difference in mean maximal heart rate between the groups. Conclusion: Significant decrease in HRV in Type 2 DM patients is suggestive of reduced parasympathetic activity or an imbalance between sympathetic and parasympathetic neural activity in them. Hence HRVdb provides a sensitive screening measure for parasympathetic dysfunction in many autonomic disorders.c dysfunction in many autonomic disorders. (author)

  14. Associated influence of hypertension and heart rate greater than 80 beats per minute on mortality rate in patients with anterior wall STEMI

    OpenAIRE

    Davidovic, Goran; Iric-Cupic, Violeta; Milanov, Srdjan

    2013-01-01

    Acute myocardial infarction as a form of coronary heart disease is characterized by permanent damage/loss of anatomical and functional cardiac tissue. Diagnosis of STEMI includes data on anginal pain and persistent ST-segment elavation. According to the numerous epidemiological studies, arterial blood pressure and heart rate are offten increased especially during the first hours of pain due to domination of sympathetic response. We wanted to investigate the associated influence of heart rate ...

  15. Resting, night-time, and 24 h heart rate as markers of cardiovascular risk in middle-aged and elderly men and women with no apparent heart disease

    DEFF Research Database (Denmark)

    Johansen, Christine D; Olsen, Rasmus H

    2013-01-01

    AimsIncreased heart rate (HR) is a predictor of all-cause and cardiovascular (CV) mortality. We tested which measure of HR had the strongest prognostic value in a population with no apparent heart disease.Methods and resultsSix hundred and fifty-three men and women between the age of 55 and 75 years were included in the Copenhagen Holter Study and underwent 48 h ambulatory electrocardiographic (ECG) monitoring. Resting HR was measured after at least 10 min of rest. Twenty-four-hour HR was derived from the mean time between normal-to-normal RR intervals (MEANNN). Night-time HR was derived from a 15 min sequence between 2:00 and 2:15 a.m. The median follow-up time was 76 months, and an adverse outcome was defined as all-cause mortality and the combined endpoint of CV death, acute myocardial infarction (AMI), and revascularization. All three measures of HR were significantly associated with all-cause mortality, also after adjustment for conventional risk factors. We found an association between all three measures of HR and CV events in analyses adjusted for sex and age. However, when adjusting for CV risk factors, the association with resting HR and 24 h HR disappeared. In a fully adjusted model, only night-time HR remained in the model, hazard ratio = 1.17 (1.05-1.30), P = 0.005.ConclusionIn middle-aged subjects with no apparent heart disease, all measures of increased HR were associated with increased mortality and CV risk. However, night-time HR was the only parameter with prognostic importance after multivariable adjustment.

  16. Heart rate variability of human in hypoxic oxygen-argon environment

    Science.gov (United States)

    Khayrullina, Rezeda; Smoleevskiy, Alexandr; Bubeev, Yuri

    Human adaptive capacity, reliability and stability in extreme environments depend primarily on the individual resistance to stresses, includes both innate and acquired components. We have conducted studies in six healthy subjects - men aged between 24 to 42 years who psychophysiological indicators acterizing the severity of stress reactions studied directly during an emergency situation, before and after it. The subjects were in a hypoxic oxygen-argon atmosphere 10 days. Cardiovascular system is one of the first to respond to stressful reaction. The method of heart rate variability (HRV) allows us to estimate balance of sympathetic and parasympathetic parts of vegetative nervous system. In the course of the baseline study it was found that resting heart rate (HR) in the examined individuals is within normal limits. During the experiment in all subjects there was a trend towards more frequent heartbeat. Each subject at one stage or another stay in a hypoxic oxygen-argon environment heart rate go beyond the group norm, but the extent and duration of these abnormalities were significantly different. Marked increase in middle heart rate during of subjects experiment, fluctuating within a wide range (from 2.3% to 29.1%). Marked increase in middle heart rate during of subjects experiment, fluctuating within a wide range (from 2.3% to 29.1%). This suggests that the ability to adapt to living in the investigated gas environment have marked individual differences. SDNN (mean square deviation of all R-R intervals) is the integral indicator of the total effect of the sinus node to the sympathetic and parasympathetic parts of vegetative nervous system, as well as indicating the higher functional reserves of the cardiovascular systems. Increase in heart rate in the majority of subject was accompanied by an increase in individual SDNN. This suggests that the parasympathetic system is able to balance the increase in activity of the sympathetic system, and functional reserves are sufficient. However, the opposite dynamic test 02 - accompanied by a decrease heart rate increase SDNN. The survey detected that all subjects marked signs of increased activity of the sympathetic nervous system. Besides when short-term exposure (up to 10 days) in most researched factor in the majority of patients was enough functional reserves to adapt to the conditions of a changed atmosphere. However, the adaptation process was accompanied by severe stress and compensatory mechanisms for longer stay in hypoxic conditions, oxygen-argon environment may develop adverse effects associated with sympathicotony.

  17. Smartphone applications (apps) for heart rate measurement in children: comparison with electrocardiography monitor.

    Science.gov (United States)

    Ho, Chi-Lin; Fu, Yun-Ching; Lin, Ming-Chih; Chan, Sheng-Ching; Hwang, Betau; Jan, Sheng-Ling

    2014-04-01

    Heart rate (HR) measurement is essential for children with abnormal heart beats. The purpose of this study was to determine whether HR measurement by smartphone applications (apps) could be a feasible alternative to an electrocardiography (ECG) monitor. A total of 40 children, median age of 4.3 years, were studied. Using four free smartphone apps, pulse rates were measured at the finger (or toe) and earlobe, and compared with baseline HRs measured by ECG monitors. Significant correlations between measured pulse rates and baseline HRs were found. Both correlation and accuracy rate were higher in the earlobe group than the finger/toe group. When HR was smartphone apps should not be used for routine medical use or used as the sole form of HR measurement because the results of their accuracy are not good enough. PMID:24259012

  18. Coronary heart disease rates within a small urban area in Belgium.

    OpenAIRE

    Backer, G.; Thys, G.; Craene, I.; Verhasselt, Y.; Henauw, S.

    1994-01-01

    STUDY OBJECTIVE--To identify geographical differences in coronary heart disease (CHD) attack rates in a small urban area and to relate these to indicators of socioeconomic class. DESIGN--CHD attack rates were calculated from data of the Ghent MONICA myocardial infarct register for the period 1983-87. The city of Ghent is subdivided into 201 sectors based on morphological, and socioeconomic characteristics. During the national census of 1981, the main determinants of residential differentiatio...

  19. Embryos in the Fast Lane: High-Temperature Heart Rates of Turtles Decline After Hatching

    OpenAIRE

    Du, Wei-Guo; Zhao, Bo; Shine, Richard

    2010-01-01

    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 no...

  20. Effect of Stimulant Medication Use by Children with ADHD on Heart Rate and Perceived Exertion

    Science.gov (United States)

    Mahon, Anthony D.; Woodruff, Megan E.; Horn, Mary P.; Marjerrison, Andrea D.; Cole, Andrew S.

    2012-01-01

    The effect of stimulant medication use by children with attention deficit/hyperactivity disorder (ADHD) on the rating of perceived exertion (RPE)--heart rate (HR) relationship was examined. Children with ADHD (n = 20; 11.3 [plus or minus] 1.8 yrs) and children without ADHD (n = 25; 11.2 [plus or minus] 2.1 yrs) were studied. Children with ADHD…

  1. Predicting METs from the heart rate index in persons with Down syndrome.

    Science.gov (United States)

    Agiovlasitis, Stamatis; Rossow, Lindy M; Yan, Huimin; Ranadive, Sushant M; Fahs, Christopher A; Motl, Robert W; Fernhall, Bo

    2014-10-01

    Persons with Down syndrome (DS) have altered heart rate modulation and very low aerobic fitness. These attributes may impact the relationship between metabolic equivalent units (METs) and the heart rate index (HRindex-the ratio between heart rate during activity and resting heart rate), thereby altering the HRindex thresholds for moderate- and vigorous-intensity physical activity. This study examined whether the relationship between METs and HRindex differs between persons with and without DS and attempted to develop thresholds for activity intensity based on the HRindex for persons with DS. METs were measured with portable spirometry and heart rate with a monitor in 18 persons with DS (25 ± 7 years; 10 women) and 18 persons without DS (26 ± 5 years; 10 women) during 6 over-ground walking trials, each lasting 6min, at the preferred walking speed and at 0.5, 0.75, 1.0, 1.25, and 1.5m/s. The relationship between METs and HRindex in the two groups was analyzed with multi-level modeling with random intercepts and slopes. Group, HRindex, and the square of HRindex were significant predictors of METs (p<0.001; R(2)=0.65). Absolute percent error did not differ significantly between groups across speeds (DS: 19.6 ± 14.4%; non-DS: 21.0 ± 14.5%). Bland-Altman plots demonstrated somewhat greater variability in the difference between actual and predicted METs in participants with than without DS. The HRindex threshold for moderate-intensity activity was 1.32 and 1.20 for persons with and without DS, respectively. The HRindex threshold for vigorous-intensity activity was 1.80 and 1.65 for persons with and without DS, respectively. Persons with DS have an altered relationship between METs and HRindex and higher HRindex thresholds for moderate- and vigorous-intensity physical activity. PMID:24981191

  2. Seasonal differences in melatonin concentrations and heart rates during sleep in obese subjects in Japan

    Science.gov (United States)

    Sato, Maki; Kanikowska, Dominika; Iwase, Satoshi; Shimizu, Yuuki; Nishimura, Naoki; Inukai, Yoko; Sato, Motohiko; Sugenoya, Junichi

    2013-09-01

    During the past several decades, obesity has been increasing globally. In Japan, obesity is defined by a BMI of 25 kg/m2 or over; 28.6 % of men and 20.6 % of women are obese. Obese people have an increased incidence of developing cardiovascular, renal, and hormonal diseases and sleep disorders. Obese people also have shortened sleep durations. We investigated seasonal differences in melatonin concentrations, heart rates, and heart rate variability during sleep in obese subjects in Japan. Five obese (BMI, 32.0 ± 4.9 kg/m2) and five non-obese (BMI, 23.2 ± 2.9 kg/m2) men participated in this study in the summer and winter. Electrocardiograms were measured continuously overnight in a climatic chamber at 26 °C with a relative humidity of 50 %. Saliva samples for melatonin were collected at 2300 hours, 0200 hours, and 0600 hours. We found that melatonin concentrations during sleep in obese subjects were significantly lower than those in non-obese subjects in the winter. Heart rate during sleep in winter was significantly higher than that in summer in both obese and non-obese subjects. Heart rate variability was not significantly different in the summer and winter in both obese and non-obese subjects. Our results show that decreased nocturnal melatonin concentrations during winter in obese men may be related to higher heart rates, and this may suggest that obese men are at an increased risk of a cardiovascular incident during sleep, especially in the winter.

  3. A New Cardiac Autonomic Function Predictor (Heart Rate Turbulence in Patients with Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Ersel Onrat

    2010-12-01

    Full Text Available Objective: Ankylosing spondylitis (AS is a chronic systemic disease. The risk of cardiovascular morbidity and mortality is high in patients with AS. Heart rate turbulence (HRT expresses ventriculophasic sinus arrhythmia and has been considered to reflect cardiac autonomic activity. It has been shown that HRT is an independent and powerful predictor of mortality. The aim of this study was to determine HRT changes in patients with AS in comparison with healthy controls. Materials and Methods: Thirty-seven patients with AS (28 men, 9 women; age: 42±2 years, range: 19-69 years according to the modified New York criteria and 37 age-and gender-matched healthy control subjects without obvious cardiovascular disease (mean age: 40±2 years, range: 23-68 years were included in this study. Mean duration of AS was 5±3 years (range: 1-20 years. All participants underwent 24-hour Holter ECG. HRT measurements, turbulence onset (TO and turbulence slope (TS were calculated with HRT View Version 0.60-0.1 software program. HRT was calculated in patients and healthy controls with at least one ventricular premature beat (VPB in their Holter recordings. TO is a measure of the early sinus acceleration and TS is the measure of the rate of sinus deceleration that follows the sinus acceleration after a VPB. Results: There were no significant differences in TO and TS between AS patients and control subjects (TO-AS: -0.0004±0.008, TO-Control: -0.118±0.006; TS-AS: 12.07±1.26, TS-Control: 10.39±1.26, respectively.Conclusion: Although cardiovascular manifestation (including increased morbidity and mortality of AS has been shown in various studies, HRT parameters, which determine the risk of sudden death, do not seem to be altered in this disease.

  4. Heart Rate Variability in Response to Pain Stimulus in VLBW Infants Followed Longitudinally During NICU Stay

    OpenAIRE

    Padhye, Nikhil S.; Williams, Amber L.; Khattak, Asif Z.; Lasky, Robert E.

    2009-01-01

    The objective of this longitudinal study, conducted in a neonatal intensive care unit, was to characterize the response to pain of high-risk very low birth weight infants (< 1500 g) from 23 through 38 weeks post-menstrual age (PMA) by measuring heart rate variability (HRV). Heart period data were recorded before, during, and after a heel lanced or wrist venipunctured blood draw for routine clinical evaluation. Pain response to the blood draw procedure and age-related changes of HRV in low-fre...

  5. The role of inhibitory heterotrimeric G proteins in the control of in vivo heart rate dynamics

    OpenAIRE

    Zuberi, Zia; Birnbaumer, Lutz; Tinker, Andrew

    2008-01-01

    Multiple isoforms of inhibitory G?-subunits (G?i1,2,3, as well as G?o) are present within the heart, and their role in modulating pacemaker function remains unresolved. Do inhibitory G?-subunits selectively modulate parasympathetic heart rate responses? Published findings using a variety of experimental approaches have implicated roles for G?i2, G?i3, and G?o in parasympathetic signal transduction. We have compared in vivo different groups of mice with global genetic deletion of Gi?1/G?i3, G?...

  6. Heart Rate Profiles of Children with and without Autism Spectrum Disorder in Response to Physical Play: A Preliminary Investigation

    Science.gov (United States)

    Breslin, Casey M.; Rudisill, Mary E.; Wadsworth, Danielle W.

    2015-01-01

    In this study, the heart rate response of children with and without autism spectrum disorder (ASD) exposed to outdoor free play sessions during preschool was examined. Participants (n = 7; four children with ASD and three children who show typical development) wore Actiheart heart rate monitors during 6 school days. Using a single-subject design,…

  7. International geographic variation in event rates in trials of heart failure with preserved and reduced ejection fraction

    DEFF Research Database (Denmark)

    Kristensen, SØren Lund; KØber, Lars

    2015-01-01

    BACKGROUND: International geographic differences in outcomes may exist for clinical trials of heart failure and reduced ejection fraction (HF-REF), but there are few data for those with preserved ejection fraction (HF-PEF). METHODS AND RESULTS: We analyzed outcomes by international geographic region in the Irbesartan in Heart Failure with Preserved systolic function trial (I-Preserve), the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM)-Preserved trial, the CHARM-Alternative and CHARM-Added HF-REF trials, and the Controlled Rosuvastatin Multinational Trial in HF-REF (CORONA). Crude rates of heart failure hospitalization varied by geographic region, and more so for HF-PEF than for HF-REF. Rates in patients with HF-PEF were highest in the United States/Canada (HF hospitalization rate 7.6 per 100 patient-years in I-Preserve; 8.8 in CHARM-Preserved), intermediate in Western Europe (4.8/100 and 4.7/100), and lowest in Eastern Europe/Russia (3.3/100 and 2.8/100). The difference between the United States/Canada versus Eastern Europe/Russia persisted after adjustment for key prognostic variables: adjusted hazard ratios 1.34 (95% confidence interval, 1.01-1.74; P=0.04) in I-Preserve and 1.85 (95% confidence interval, 1.17-2.91; P=0.01) in CHARM-Preserved. In HF-REF, rates of HF hospitalization were slightly lower in Western Europe compared with other regions. For both HF-REF and HF-PEF, there were few regional differences in rates of all-cause or cardiovascular mortality. CONCLUSIONS: The differences in event rates observed suggest there is international geographic variation in 1 or more of the definition and diagnosis of HF-PEF, the risk profile of patients enrolled, and the threshold for hospitalization, which has implications for the conduct of future global trials.

  8. Acute responses of blood pressure, heart rate and rating of perceived exertion in hypertensive patients

    Directory of Open Access Journals (Sweden)

    César Giovanni García Cardona

    2007-06-01

    Full Text Available Objective: To assess and compare acute responsesin arterial blood pressure (BP, heartrate (HR and rating of perceived exertion scale(PES during a variable-resistance weight-liftingcircuit (WC versus submaximal aerobicexercise in cycloergometer (AE in individualswith hypertension scaled I and II.Methods: 21 subjects with controlled hypertensionscaled I and II (8 males and 13 females,15 actives and 6 sedentary, age 56±5.9 yearswere evaluated. All the participants receivedtraining about warm-up, use of PES, and respiratoryand weight lifting machines techniquesin exercise. All underwent a single session ofWC in six stations at 50% 1RM and a singlesession of AE at 70%-80% FCmax, in intervalsof one week. BP, HR and PES was measured inboth exercises.Results: To compare responses in both typesof exercise, at Test was used. It found a lowerresponse of HR (p<0.001, systolic BP (p<0.005and PES (p<0.005 during WC. Greater diastolicBP response was found in WC, although it wasnot significative (p=0.139. Sedentary subjectsshowed greater increases. Responses of variableswere similar between stations in WC.Conclusion: This study evidenced a similarbehavior of acute cardiovascular responses and PESduring WC versus AE in hypertensive subjects. Itshowed a lower pressure response during WC insubjects with previous aerobic training.

  9. Quantitative assessment of thallium myocardial washout rate: Importance of peak heart rate and lung thallium uptake in defining normal values

    International Nuclear Information System (INIS)

    Traditionally, the results of exercise thallium scintigraphy were interpreted by transient defect analysis using initial and delayed images. Recently, washout rate analysis has been used for the relative quantification of exercise thallium scintigraphy. A diffuse slow washout from all myocardial regions has been defined as the indicator of extensive coronary artery disease. However, slow washout has occasionally been observed in normal cases and in healthy myocardial segments which are not supplied by a stenosed artery in patients with single or double vessel disease. We evaluate the factors influencing washout rate in 100 normal patients and 63 patients with angina pectoris (33 cases of single vessel disease and 30 cases of double vessel disease). The washout rates were calculated using circumferential profile analysis. In normal patients, washout rate was closely related to peak heart rate (r=0.72) and inversely related to lung thallium uptake (r=-0.56). A diffuse slow washout was observed in seven (7%) of 100 normal patients, six (18%) of 33 cases of single vessel disease and eight (24%) of 30 cases of double vessel disease. The patients with diffuse slow washout showed significantly higher lung thallium uptake values and lower peak heart rates than those without diffuse slow washout (P<0.01). Thus, this false positive slow washout should be considered in the interpretation of quantitative exercise thallium scintigraphy. (orig.)rig.)

  10. The slope of the oxygen pulse curve does not depend on the maximal heart rate in elite soccer players

    Scientific Electronic Library Online (English)

    Raphael Rodrigues, Perim; Gabriel Ruiz, Signorelli; Jonathan, Myers; Ross, Arena; Claudio Gil Soares de, Araújo.

    Full Text Available INTRODUCTION: It is unknown whether an extremely high heart rate can affect oxygen pulse profile during progressive maximal exercise in healthy subjects. OBJECTIVE: Our aim was to compare relative oxygen pulse (adjusted for body weight) curves in athletes at their maximal heart rate during treadmill [...] cardiopulmonary exercise testing. METHODS: A total of 180 elite soccer players were categorized in quartiles according to their maximum heart rate values (n = 45). Oxygen consumption, maximum heart rate and relative oxygen pulse curves in the extreme quartiles, Q1 and Q4, were compared at intervals corresponding to 10% of the total duration of a cardiopulmonary exercise testing. RESULTS: Oxygen consumption was similar among all subjects during cardiopulmonary exercise testing; however subjects in Q1 started to exhibit lower maximum heart rate values when 20% of the test was complete. Conversely, the relative oxygen pulse was higher in this group when cardiopulmonary exercise testing was 40% complete (p

  11. A cross-sectional study on upright heart rate and BP changing characteristics: basic data for establishing diagnosis of postural orthostatic tachycardia syndrome and orthostatic hypertension

    Science.gov (United States)

    Zhao, Juan; Han, Zhenhui; Zhang, Xi; Du, Shuxu; Liu, Angie Dong; Holmberg, Lukas; Li, Xueying; Lin, Jing; Xiong, Zhenyu; Gai, Yong; Yang, Jinyan; Liu, Ping; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

    2015-01-01

    Objective We aimed to determine upright heart rate and blood pressure (BP) changes to suggest diagnostic criteria for postural orthostatic tachycardia syndrome (POTS) and orthostatic hypertension (OHT) in Chinese children. Methods In this cross-sectional study, 1449 children and adolescents aged 6–18?years were randomly recruited from two cities in China, Kaifeng in Henan province and Anguo in Hebei province. They were divided into two groups: 844 children aged 6–12?years (group I) and 605 adolescents aged 13–18?years (group II). Heart rate and BP were recorded during an active standing test. Results 95th percentile (P95) of ? heart rate from supine to upright was 38?bpm, with a maximum upright heart rate of 130 and 124?bpm in group I and group II, respectively. P95 of ? systolic blood pressure (SBP) increase was 18?mm?Hg and P95 of upright SBP was 132?mm?Hg in group I and 138?mm?Hg in group II. P95 of ? diastolic blood pressure (DBP) increase was 24?mm?Hg in group I and 21?mm?Hg in group II, and P95 of upright DBP was 89?mm?Hg in group I and 91?mm?Hg in group II. Conclusions POTS is suggested when ? heart rate is ?38?bpm (for easy memory, ?40?bpm) from supine to upright, or maximum heart rate ?130?bpm (children aged 6–12?years) and ?125?bpm (adolescents aged 13–18?years), associated with orthostatic symptoms. OHT is suggested when ? SBP (increase) is ?20?mm?Hg, and/or ? DBP (increase) ?25?mm?Hg (in children aged 6–12?years) or ?20?mm?Hg (in adolescents aged 13–18?years) from supine to upright; or upright BP?130/90?mm?Hg (in children aged 6–12?years) or ?140/90?mm?Hg (in adolescents aged 13–18?years). PMID:26033944

  12. Correlation of heart rate turbulence with sympathovagal balance in patients with acute myocardial infarction.

    Science.gov (United States)

    Iwasaki, Masayoshi; Yuasa, Fumio; Yuyama, Reisuke; Mimura, Jun; Kawamura, Akihiro; Motohiro, Masayuki; Yo, Masue; Sugiura, Tetsuro; Iwasaka, Toshiji

    2005-01-01

    To examine the relationship among heart rate turbulence parameters, arterial baroreflex sensitivity, and cardiac sympathetic nerve activity, 15 patients with acute myocardial infarction, presenting with sinus rhythm and > or = 3 ventricular premature beats/24 hr were studied at least 2 weeks after acute myocardial infarction. Turbulence onset (TO) and turbulence slope (TS) were averaged from 3 respective ventricular premature beats. Early heart-to-mediastinum ratio (H/M), delayed H/M, and washout rate were calculated from iodine-123-metaiodobenzylguanidine (123I MIBG) scintigraphy. Arterial baroreflex sensitivity was calculated by phenyrephrine method. Arterial baroreflex sensitivity correlated significantly with TO (r = - 0.75, p < .01) and TS (r = 0.53, p < .05). TO had no correlations with early H/M, delayed H/M, and washout rate. There were no significant correlations between TS and early H/M. However, TS had significant correlation with delayed H/M (r = 0.74, p < .01) and washout rate (r = -0.71, p < .01). Thus, heart rate turbulence of TO and TS parameters depend on sympathovagal balance. PMID:15835388

  13. The relation of ambulatory heart rate with all-cause mortality among middle-aged men: a prospective cohort study.

    Science.gov (United States)

    Korshøj, Mette; Lidegaard, Mark; Kittel, France; Van Herck, Koen; De Backer, Guy; De Bacquer, Dirk; Holtermann, Andreas; Clays, Els

    2015-01-01

    The aim of this study was to investigate the association between average 24-hour ambulatory heart rate and all-cause mortality, while adjusting for resting clinical heart rate, cardiorespiratory fitness, occupational and leisure time physical activity as well as classical risk factors. A group of 439 middle-aged male workers free of baseline coronary heart disease from the Belgian Physical Fitness Study was included in the analysis. Data were collected by questionnaires and clinical examinations from 1976 to 1978. All-cause mortality was collected from the national mortality registration with a mean follow-up period of 16.5 years, with a total of 48 events. After adjustment for all before mentioned confounders in a Cox proportional hazards regression analysis, a significant increased risk for all-cause mortality was found among the tertile of workers with highest average ambulatory heart rate compared to the tertile with lowest ambulatory heart rate (Hazard ratio = 3.21, 95% confidence interval: 1.22-8.44). No significant independent association was found between resting clinic heart rate and all-cause mortality. The study indicates that average 24-hour ambulatory heart rate is a strong predictor of all-cause mortality independent from resting clinic heart rate, cardiorespiratory fitness, occupational and leisure time physical activity and other classical risk factors among healthy middle-aged workers. PMID:25811891

  14. Heart Health

    Science.gov (United States)

    ... However, the number of heart beats per minute (heart rate) at rest does not change as you age. Many of the problems older people have with their heart and blood vessels are really caused by disease, ...

  15. Low heart rate as a risk factor for child and adolescent proactive aggressive and impulsive psychopathic behavior.

    Science.gov (United States)

    Raine, Adrian; Fung, Annis Lai Chu; Portnoy, Jill; Choy, Olivia; Spring, Victoria L

    2014-01-01

    Although low resting heart rate has been viewed as a well-replicated biological correlate of child and adolescent antisocial behavior, little is known about how it interacts with psychosocial adversity in predisposing to both reactive-proactive aggression and psychopathy, and whether this relationship generalizes to an East Asian population. This study tests the hypothesis that low resting heart rate will be associated with aggression and psychopathic traits, and that heart rate will interact with adversity in predisposing to these antisocial traits. Resting heart rate was assessed in 334 Hong Kong male and female schoolchildren aged 11-17 years. A social adversity index was calculated from a psychosocial interview of the parent, while parents assessed their children on the Reactive-Proactive Aggression Questionnaire and the Antisocial Personality Screening Device. Low resting heart rate was significantly associated with higher proactive aggression, impulsive features of psychopathy, and total child psychopathy. Low resting heart rate interacted with high psychosocial adversity in explaining higher reactive (but not proactive) aggression, as well as impulsive psychopathy. These findings provide support for a biosocial perspective of reactive aggression and impulsive psychopathy, and document low resting heart rate as a robust correlate of both childhood impulsive psychopathic behavior and proactive aggression. To our knowledge, this study is the first to document low resting heart rate as a correlate of child psychopathy and the second to establish low heart rate as a risk factor of antisocial behavior in an East Asian population. The findings provide further evidence for both low resting heart rate as a potential biomarker for childhood psychopathic and aggressive behavior, and also a biosocial perspective on childhood antisocial behavior. PMID:24604759

  16. A comparative study of nebivolol and (S atenolol on blood pressure and heart rate on essential hypertensive patients

    Directory of Open Access Journals (Sweden)

    Sahana G

    2010-01-01

    Full Text Available Objectives: To study the effect of nebivolol 5 mg once daily versus (S-atenolol 25 mg once daily in patients with essential hypertension. Materials and Methods: A prospective study was conducted at RLJH and Research Centre which included 30 patients in each group with essential hypertension. The sex, age, presenting illness, and family history of the patients were recorded. Investigations such as blood sugar, urine analysis, kidney function test, lipid profile, and ECG were performed before starting the treatment. Any adverse effects during the treatment were noted. Blood pressure and heart rate were recorded at baseline and during follow-up. One group received nebivolol 5 mg once daily and other group (Satenolol 25 mg once daily. Patients were followed-up every 15 days for 3 months. Results: Nebivolol group had 18 males and 12 females with mean age 50.6 ± 9.5 years, (S-atenolol had 16 males and 14 females with mean age 54.4 ± 9 years. Patients receiving nebivolol and (S-atenolol showed a significant fall (P heart rate at the end of first, second, and third month when compared to baseline. The difference in fall in SBP and DBP was insignificant between the groups, but fall in heart rate was significant (P Conclusion: Reduction of blood pressure with nebivolol and (Satenolol was similar, but fall in blood pressure from baseline was highly significant in both groups.

  17. Resting heart rate is associated with cardiovascular and all-cause mortality after adjusting for inflammatory markers: The Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Jensen, Magnus Thorsten; Marott, Jacob L

    2012-01-01

    Aims: To investigate the association between resting heart rate (RHR) and markers of chronic low-grade inflammation. Also, to examine whether elevated resting heart rate is independently associated with cardiovascular and all-cause mortality in the general population, or whether elevated RHR is merely a marker of chronic low-grade inflammation. Methods and results: A group of 6518 healthy subjects from the the Danish general population were followed for 18 years during which 1924 deaths occurred. Subjects underwent assessment of baseline RHR, conventional cardiovascular risk factors, high-sensitivity C-reactive protein (hsCRP), and fibrinogen. RHR was associated with hsCRP and fibrinogen in uni- and multivariate models (p <0.0001). A 10 beats per minute increase in RHR was associated with increased cardiovascular and all-cause mortality in univariate models - HR (95%CI) (1.21 (1.14-1.29) and 1.15 (1.11-1.19); multivariate models adjusted for conventional risk factors - 1.16 (1.09-1.24) and 1.10 (1.06-1.14); multivariate models including hsCRP - 1.14 (1.07-1.22) and 1.09 (1.05-1.14); fibrinogen - 1.15 (1.07-1.22) and 1.09 (1.05-1.14); and both hsCRP and fibrinogen - 1.14 (1.07-1.22) and 1.09 (1.05-1.14). Conclusion: RHR was associated with markers of chronic low-grade inflammation. However, RHR remained associated with both cardiovascular and all-cause mortality after adjusting for markers of chronic low-grade inflammation. This suggests that RHR is an independent risk factor for cardiovascular and all-cause mortality, and not merely a marker of chronic low-grade inflammation.

  18. Heart rate variability measurement and clinical depression in acute coronary syndrome patients: narrative review of recent literature

    Directory of Open Access Journals (Sweden)

    Harris PR

    2014-07-01

    Full Text Available Patricia RE Harris,1 Claire E Sommargren,2 Phyllis K Stein,3 Gordon L Fung,4,5 Barbara J Drew6,7 1ECG Monitoring Research Lab, 2Department of Physiological Nursing, School of Nursing, University of California, San Francisco, CA, USA; 3Heart Rate Variability Laboratory, School of Medicine, Washington University, St Louis, MO, USA; 4Asian Heart & Vascular Center at Mount Zion, Division of Cardiology, University of California, 5Cardiology Consultation Service, Cardiac Noninvasive Laboratory, and The Enhanced External Counterpulsation Unit, Department of Medicine, University of California, San Francisco Medical Center, 6Division of Cardiology, 7Department of Physiological Nursing, School of Nursing, University of California, San Francisco, CA, USA Aim: We aimed to explore links between heart rate variability (HRV and clinical depression in patients with acute coronary syndrome (ACS, through a review of recent clinical research literature. Background: Patients with ACS are at risk for both cardiac autonomic dysfunction and clinical depression. Both conditions can negatively impact the ability to recover from an acute physiological insult, such as unstable angina or myocardial infarction, increasing the risk for adverse cardiovascular outcomes. HRV is recognized as a reflection of autonomic function. Methods: A narrative review was undertaken to evaluate state-of-the-art clinical research, using the PubMed database, January 2013. The search terms “heart rate variability” and “depression” were used in conjunction with “acute coronary syndrome”, “unstable angina”, or “myocardial infarction” to find clinical studies published within the past 10 years related to HRV and clinical depression, in patients with an ACS episode. Studies were included if HRV measurement and depression screening were undertaken during an ACS hospitalization or within 2 months of hospital discharge. Results: Nine clinical studies met the inclusion criteria. The studies' results indicate that there may be a relationship between abnormal HRV and clinical depression when assessed early after an ACS event, offering the possibility that these risk factors play a modest role in patient outcomes. Conclusion: While a definitive conclusion about the relevance of HRV and clinical depression measurement in ACS patients would be premature, the literature suggests that these measures may provide additional information in risk assessment. Potential avenues for further research are proposed. Keywords: autonomic nervous system, depressive disorder, outcomes research, risk assessment

  19. Analysis of Heart Rate and Blood Pressure Time Series Using a Two-Dimensional Autoregressive Model

    Science.gov (United States)

    Yoshida, Yutaka; Yokoyama, Kiyoko; Uehara, Akihiko; Kurata, Chinori; Takata, Kazuyuki

    We analyzed the feedback relationship between short-term fluctuations in heart rate and blood pressure in healthy persons and heart failure patients. Parameters derived from the feedback relationship between heart rate and blood pressure have been proposed. The purpose of the present study is to apply these parameters in estimating autonomic function or measuring physiological and mental workload. Electrocardiographs and beat-to-beat blood pressure were recorded in supine position at rest. The blood pressure was measured using arterial tonometry. The R—R interval and systolic blood pressure were fitted to two-dimensional autoregressive models, the relative power contribution in the frequency domain was calculated. The proposed parameters are the power contribution in the low-frequency range ( 0-0.15 Hz ) [ RS_LF, SR_LF ] and the power contribution in the high-frequency range ( 0.15-0.5 Hz ) [ RS_HF, SR_HF ]. RS_LF was significantly different between healthy persons and heart failure patients ( pheart failure. There were no correlations between the proposed parameters and the usual indices to evaluate autonomic function. It is considered that the proposed parameters can be used to evaluate physiological states that cannot be evaluated using existing methods.

  20. Increased non-Gaussianity of heart rate variability predicts cardiac mortality after an acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    JunichiroHayano

    2011-09-01

    Full Text Available Non-Gaussianity index (? is a new index of heart rate variability (HRV that characterizes increased probability of the large heart rate deviations from its trend. A previous study has reported that increased ? is an independent mortality predictor among patients with chronic heart failure. The present study examined predictive value of ? in patients after acute myocardial infarction (AMI. Among 670 post-AMI patients, we performed 24-hr Holter monitoring to assess ? and other HRV predictors, including standard deviation of normal-to-normal interval, very-low frequency power, scaling exponent ?1 of detrended fluctuation analysis, deceleration capacity, and heart rate turbulence (HRT. At baseline, ? was not correlated substantially with other HRV indices (|r| <0.4 with either indices and was decreased in patients taking ?-blockers (P = 0.04. During a median follow up period of 25 months, 45 (6.7% patients died (32 cardiac and 13 non-cardiac and 39 recurrent nonfatal AMI occurred among survivors. While all of these HRV indices but ? were significant predictors of both cardiac and non-cardiac deaths, increased ? predicted exclusively cardiac death (RR [95% CI], 1.6 [1.3-2.0] per 1 SD increment, P <0.0001. The predictive power of increased ? was significant even after adjustments for clinical risk factors, such as age, diabetes, left ventricular function, renal function, prior AMI, heart failure, and stroke, Killip class, and treatment ([95% CI], 1.4 [1.1-2.0] per 1 SD increment, P = 0.01. The prognostic power of increased ? for cardiac death was also independent of all other HRV indices and the combination of increased ? and abnormal HRT provided the best predictive model for cardiac death. Neither ? nor other HRV indices was an independent predictor of AMI recurrence. Among post-AMI patients, increased ? is associated exclusively with increased cardiac mortality risk and its predictive power is independent of clinical risk factors and of other HRV predictors.

  1. Maximum Heart Rate and Blood Pressure in Exercise-Trained and Sedentary Healthy Males in Ilorin, Nigeria

    Directory of Open Access Journals (Sweden)

    I.P. Oyeyipo

    2011-01-01

    Full Text Available The effect of exercise-training on heart rate and blood pressure both at rest and after an all out effort on a bicycle ergometer was studied in 87 healthy Nigerian males. The age groups of the subjects are 15-19, 20-24, 25-29 and 30-34 years. Results showed that exercise-trained individuals have a significantly lower resting rate (p<0.05 and a significantly lower maximum heart rate (p<0.05 than sedentary individuals in all the age groups. However, no significant difference was recorded in the blood pressure (both systole and diastole between exercise-trained and sedentary individuals in all the age groups. Endurance training, through improvement of heart efficiency may improve cardiac autonomic balance; increasing parasympathetic while decreasing sympathetic stimulation of the heart. Exercise training results in markedly lower heart rate readings in exercise-trained individuals compared with sedentary individuals.

  2. Q-T interval (QTc) in patients with cirrhosis: relation to vasoactive peptides and heart rate.

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Gülberg, V.

    2007-01-01

    OBJECTIVE: Prolonged Q-T interval (QT) has been reported in patients with cirrhosis who also exhibit profound abnormalities in vasoactive peptides and often present with elevated heart rate (HR). The aim of this study was to relate QT to the circulating level of endothelins (ET-1 and ET-3) and calcitonin gene-related peptide (CGRP) in patients with cirrhosis. In addition, we studied problems with HR correction of QT. MATERIAL AND METHODS: Forty-eight patients with cirrhosis and portal hypertension were studied during a haemodynamic investigation. Circulating levels of ETs and CGRP were determined by radioimmunoassays. Correction of QT for HR above 60 beats per min was performed using the methods described by Bazett (QT(C)) and Fridericia (QT(F)). RESULTS: Prolonged QT(C) (above 440 ms), found in 56% of the patients, was related to the presence of significant portal hypertension and liver dysfunction (p < 0.05 to 0.001), but not to elevated ET-1, ET-3 or CGRP. When corrected according to Bazett, QT(C) showed no significant relation to differences in HR between patients (r = 0.07, ns). QTF showed some undercorrection of HR (r = -0.36; p < 0.02). During HR variation in the individual patient, QT(C) revealed a small but significant overcorrection (2.6 ms per heartbeat per min; p < 0.001). This value was significantly (p < 0.02) smaller with QTF (1.2 ms per heartbeat per min). CONCLUSIONS: The prolonged QT(C) in cirrhosis is related to liver dysfunction and the presence of portal hypertension, but not to the elevated powerful vasoconstrictor (ET-1) or vasodilator (CGRP, ET-3) peptides. The problems with correction of the QT for elevated HR in cirrhosis are complex, and the lowest HR should be applied for determination of the QT.

  3. Resting heart rate influences right ventricular volume in repaired tetralogy of Fallot.

    Science.gov (United States)

    Jolley, Matthew; Hickey, Kelsey; Annese, David; Gauvreau, Kimberlee; Geva, Tal; Valente, Anne Marie; Powell, Andrew J

    2015-04-01

    The aim of this study is to examine the impact of heart rate (HR) on right ventricular end-diastolic volume indexed to body surface area (RVEDVi) in patients with repaired tetralogy of Fallot (TOF). In this cross-sectional study, an institutional database search identified all patients with repaired TOF who underwent cardiac magnetic resonance (CMR) and had a Holter study within 3 months. The association of HR on Holter, HR at the time of CMR, and other clinical and CMR parameters on RVEDVi was explored with univariate and then multivariable models. In the study group (n = 161, median age 23 years), a lower mean Holter HR was associated with a larger RVEDVi (p = 0.004). In a model that also included pulmonary regurgitation fraction, tricuspid regurgitation grade, RV ejection fraction, age at CMR, and gender, mean Holter HR remained associated with RVEDVi (p < 0.0001); for a decrease of 1 bpm, mean RVEDVi increased by 1.09 ml/m(2). When limiting to those with a Holter within 5 days of CMR (n = 70), the impact of mean Holter HR on RVEDVi was stronger (-1.9 ml/m(2)/bpm). HR at time of CMR had a significant but less pronounced relationship to RVEDVi (-0.58 ml/m(2)/bpm, p = 0.002). In conclusion, in repaired TOF patients, a lower HR was significantly associated with a larger RVEDVi. This relationship was stronger with a shorter time interval between the Holter and CMR, and stronger for the mean HR on Holter than for the HR at CMR. Accounting for HR in the interpretation of RVEDVi may impact decisions regarding pulmonary valve replacement and the interpretation of serial CMR data. PMID:25527228

  4. Heart rate variability and depressed mood in physical education students: a longitudinal study.

    Science.gov (United States)

    Pichon, Aurélien; Nuissier, Frédéric; Chapelot, Didier

    2010-08-25

    Autonomic nervous system (ANS) activity, and more specifically its parasympathetic component, has been reported to be associated with depression. The objective of this longitudinal study was to assess whether changes in heart rate variability (HRV) and in depressive moods were interrelated in healthy young subjects. Thirty students in physical education with a high physical load, were followed over the university year at 3 periods: October (P1), February (P2) and May (P3). Depressive mood was assessed by the score on the Depression subscale of the profile of mood state (POMS) questionnaire. HRV was assessed in supine and during an active orthostatic test with total power (TPms(2)) as the sum of the very low (VLF), low (LF) and high frequency (HF) bands, LF/HF ratio representing sympathetic and HFms(2) parasympathetic modulations. Results showed that changes in Depression scores between P1 and P2 were negatively and positively associated with changes in TPms(2), LFms(2), and HFms(2) in supine position and during orthostatism respectively. Although Anger/Aggressivity, Fatigue, and Vigor scores of the POMS were also correlated with changes in some HRV indices, Depression was the only significant predictive factor of changes in TPms(2) and HFms(2) between P1 and P2 in supine position and during orthostatism. These results were not observed between P2 and P3. In conclusion, in a healthy young sample of population, changes in depressive moods are associated with changes in total rhythmical power of HRV and more specifically its parasympathetic component. PMID:20447874

  5. A practical approach to parameter estimation applied to model predicting heart rate regulation

    DEFF Research Database (Denmark)

    Olufsen, Mette; Ottesen, Johnny T.

    2013-01-01

    Mathematical models have long been used for prediction of dynamics in biological systems. Recently, several efforts have been made to render these models patient specific. One way to do so is to employ techniques to estimate parameters that enable model based prediction of observed quantities. Knowledge of variation in parameters within and between groups of subjects have potential to provide insight into biological function. Often it is not possible to estimate all parameters in a given model, in particular if the model is complex and the data is sparse. However, it may be possible to estimate a subset of model parameters reducing the complexity of the problem. In this study, we compare three methods that allow identification of parameter subsets that can be estimated given a model and a set of data. These methods will be used to estimate patient specific parameters in a model predicting baroreceptor feedback regulation of heart rate during head-up tilt. The three methods include: structured analysis of the correlation matrix, analysis via singular value decomposition followed by QR factorization, and identification of the subspace closest to the one spanned by eigenvectors of the model Hessian. Results showed that all three methods facilitate identification of a parameter subset. The “best” subset was obtained using the structured correlation method, though this method was also the most computationally intensive. Subsets obtained using the other two methods were easier to compute, but analysis revealed that the final subsets contained correlated parameters. In conclusion, to avoid lengthy computations, these three methods may be combined for efficient identification of parameter subsets.

  6. Lower heart rate variability is associated with cancer-related fatigue in breast cancer survivors

    Directory of Open Access Journals (Sweden)

    Alexandra Dupont

    2012-09-01

    Full Text Available Background : Fatigue is the most common and distressing symptom reported by breast cancer survivors and yet the pathophysiology of cancer-related fatigue remains largely unknown. Fatigue is associated with lower parasympathetic and higher sympathetic nervous system activity in non-cancer samples, but only one study has demonstrated this same relationship in breast cancer survivors. This study evaluates the relationship between fatigue and basal autonomic nervous system activity as measured by heart rate variability (HRV in a sample of breast cancer survivors. Methods : Women who had been diagnosed with early stage breast cancer before the age of 50 were recruited from the UCLA tumor registry and completed psychological questionnaires, including measures of fatigue. A subset of these women (n=30 participated in a follow-up study in which they completed measures of fatigue, energy and mood four times per day for 5 days using electronic diaries, provided 3 days of saliva samples for cortisol assessment and underwent physiological assessment including electrocardiogram (ECG. HRV was assessed via ECG R-R wave spectral and time sequence analysis. Results : Questionnaire measures of fatigue were negatively associated with indices of parasympathetic nervous system activity, B=???3.85, p?=?0.04 for RMSSD (root of the mean squared difference of successive normal to normal waves and B=???76.97, p?=?0.04 for LF power % (low-frequency wave power percentage. Daily fatigue was also associated with lower basal HRV, B=???15.1, p?=?0.04 for RMSSD. However, fatigue indices were not associated with sympathetic nervous system activity as measured by low- to high-frequency wave ratio. Of note, fatigue was not associated with average daily cortisol output (AUC. Conclusions : Lower HRV has been associated with increased chronic inflammation, which is elevated in cancer survivors reporting persistent fatigue, thus providing insight into potential system interactions underlying the mechanisms for cancer-related fatigue.

  7. Different Effects of Right and Left Stellate Ganglion Block on Systolic Blood Pressure and Heart Rate

    Directory of Open Access Journals (Sweden)

    Hiroshi Goto

    2013-05-01

    Full Text Available Purpose: Whether or not right and left stellate ganglion blocks (SGB affect blood pressure (BP and heart rate (HR differently has been controversial. The aim of this study was to analyze BP and HR changes after large numbers of right or left SGBs. Methods: A total of 16,404 right SGBs and 13,766 left SGBs were performed with 6 ml of 1% mepivacaine using the anterior paratracheal approach at C6. Changes in systolic BP and HR 30 min after SGBs were compared to the baseline values. Results: Systolic BP decreased by 25 to 49 mmHg in 10.93% and more than 50 mmHg in 0.67% of 16,404 right SGBs. Those percentages were significantly higher than corresponding percentages; 8.43% and 0.49% of 13,766 left SGBs (P -49 mmHg in 5.74% and more than 50 mmHg in 0.52% of left SGBs, and in 4.15% and 0.18% of right SGBs (P Right SGB caused marked reduction in HR (greater than 30 beats/min, more than left SGB (4.22% versus 2.70%, P Conclusions: Both right and left SGBs could produce clinically significant hypertension and hypotension, and also severe bradycardia. However, right SGB produces a higher incidence of significant reductions in systolic BP and HR, compared to left SGB. On the other hand, left SGB produces a significant increase in systolic BP compared to right SGB. Those differences likely stem from the hemispheric asymmetry in autonomic cardiovascular control.

  8. Resting heart rate and risk of adverse cardiovascular outcomes in asymptomatic aortic stenosis : the SEAS study

    DEFF Research Database (Denmark)

    Greve, Anders M; Bang, Casper N

    2015-01-01

    BACKGROUND: An elevated resting heart rate (RHR) may be an early sign of cardiac failure, but its prognostic value during watchful waiting in asymptomatic aortic stenosis (AS) is largely unknown. METHODS: RHR was determined by annual ECGs in the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study of asymptomatic mild-to-moderate AS patients. Primary endpoint in this substudy was major cardiovascular events (MCEs) and secondary outcomes its individual components. Multivariable Cox-models using serially-measured RHR were used to examine the prognostic impact of RHR per se. RESULTS: 1563 patients were followed for a mean of 4.3years (6751 patient-years of follow-up), 553 (35%) MCEs occurred, 10% (n=151) died, including 75 cardiovascular deaths. In multivariable analysis, baseline RHR was independently associated with MCEs (HR 1.1 per 10min(-1) faster, 95% CI: 1.0-1.3) and cardiovascular mortality (HR 1.3 per 10min(-1) faster, 95% CI: 1.0-1.7, both p?0.03). Updating RHR with annual in-study reexaminations, time-varying RHR was highly associated with excess MCEs (HR 1.1 per 10min(-1) faster, 95% CI: 1.1-1.3) and cardiovascular mortality (HR 1.4 per 10min(-1) faster, 95% CI: 1.2-1.7, both p?0.006). The association of RHR with MCEs and cardiovascular mortality was not dependent on atrial fibrillation status (both p?0.06 for interaction). CONCLUSIONS: RHR is independently associated with MCEs and cardiovascular death in asymptomatic AS (Clinicaltrials.gov; unique identifier NCT00092677).

  9. Auricular acupressure to improve menstrual pain and menstrual distress and heart rate variability for primary dysmenorrhea in youth with stress.

    Science.gov (United States)

    Wang, Yu-Jen; Hsu, Chin-Che; Yeh, Mei-Ling; Lin, Jaung-Geng

    2013-01-01

    Background. Dysmenorrhea and accompanying symptoms can have a negative impact on academic achievement, physical activity and functioning, and quality of life. Unfortunately, stress increases the sensitivity and severity of pain, activating sympathetic responses while inhibiting parasympathetic responses. Objective. This study used objective, physiological measurements to evaluate the effects of auricular acupressure on menstrual pain and menstrual distress in young college students with primary dysmenorrhea across two menstrual cycles. The aim was to determine if significant differences could be detected between the intervention and follow-up phases after controlling life stress. Design. A one-group experimental research design was used, and repeated measurements and followups were done. Thirty-two women completed questionnaires and physiological parameters were measured. Results. Significant differences between the intervention and follow-up phases were found for high frequency (HF) and blood pressure on day 1 and no significant differences in menstrual pain and menstrual distress, heart rate variability, low frequency (LF), LF/HF ratio, or heart rate. Conclusion. Auricular acupressure effectively increases parasympathetic activity to maintain autonomic function homeostasis in young women with primary dysmenorrhea and may have a value in alleviating menstrual pain and menstrual distress in a high-stress life. Future studies should consider stress, stimulus dose of auricular acupressure, severity of menstrual pain, and a longitudinal research design. PMID:24416063

  10. A new algorithm for wavelet-based heart rate variability analysis

    CERN Document Server

    García, Constantino A; Vila, Xosé; Márquez, David G

    2014-01-01

    One of the most promising non-invasive markers of the activity of the autonomic nervous system is Heart Rate Variability (HRV). HRV analysis toolkits often provide spectral analysis techniques using the Fourier transform, which assumes that the heart rate series is stationary. To overcome this issue, the Short Time Fourier Transform is often used (STFT). However, the wavelet transform is thought to be a more suitable tool for analyzing non-stationary signals than the STFT. Given the lack of support for wavelet-based analysis in HRV toolkits, such analysis must be implemented by the researcher. This has made this technique underutilized. This paper presents a new algorithm to perform HRV power spectrum analysis based on the Maximal Overlap Discrete Wavelet Packet Transform (MODWPT). The algorithm calculates the power in any spectral band with a given tolerance for the band's boundaries. The MODWPT decomposition tree is pruned to avoid calculating unnecessary wavelet coefficients, thereby optimizing execution t...

  11. Effect of chloride content in water on heart rate in narrow-clawed crayfish (Astacus leptodactylus

    Directory of Open Access Journals (Sweden)

    P. Kozák

    2009-01-01

    Full Text Available A non-invasive method of recording cardiac activity was used to examine the impact of chloride level in water on narrow-clawed crayfish. This method permits one to record heart rate without any harm to the animal, and also locates changes in the shape and amplitude parameters of the response, which characterized the crayfish functional state. Altogether, eight levels of chloride (100, 400, 800, 1600, 3200, 6400, 12800 and 25600 mg·L?1 NaCl were evaluated. Already at low levels some crayfish were influenced. A clear reaction was evident starting from 3200 mg·L?1 NaCl. On the contrary, crayfish showed a high tolerance to high chloride levels, and the heart rate and stress index returned to normal within a few minutes or hours after NaCl addition.

  12. Combined use of autogenic therapy and biofeedback in training effective control of heart rate by humans

    Science.gov (United States)

    Cowings, P. S.

    1977-01-01

    Experiments were performed on 24 men and women (aged 20-27 yr) in three equal groups who were taught to control their own heart rates by autogenic training and biofeedback under dark and sound-isolated conditions. Group I was parasympathetic dominant, group II was sympathetic dominant, and group III consisted of parasympathetic-dominant subjects and controls who received only biofeedback of their own heart rates. The results corroborate three hypotheses: (1) subjects with para-sympathetic-dominant autonomic profiles perform in a way that is both qualitatively and quantitatively different from subjects with sympathetic-dominant autonomic profiles; (2) tests of interindividual variability yield data relevant to individual performance in visceral learning tasks; and (3) the combined use of autogenic training, biofeedback, and verbal feedback is suitable for conditioning large stable autonomic responses in humans.

  13. Effect of concrete block weight and wall height on electromyographic activity and heart rate of masons.

    Science.gov (United States)

    Anton, D; Rosecrance, J C; Gerr, F; Merlino, L A; Cook, T M

    2005-08-15

    Work-related musculoskeletal disorders (MSDs) are common among construction workers, such as masons. Few interventions are available to reduce masons' exposure to heavy lifting, a risk factor for MSDs. The purpose of this study was to determine whether one such intervention, the use of light-weight concrete blocks (LWBs), reduces physiological loads compared to standard-weight blocks (SWBs). Using a repeated measures design, 21 masons each constructed two 32-block walls, seven courses (rows) high, entirely of either SWBs or LWBs. Surface electromyography (EMG), from arm and back muscles, and heart rate was sampled. For certain muscles, EMG amplitudes were slightly lower when masons were laying LWBs compared to SWBs. Upper back and forearm extensor EMG amplitudes were greater for the higher wall courses for both block weights. There were no significant differences in heart rate between the two blocks. Interventions that address block weight and course height may be effective for masons. PMID:16253947

  14. A Comparison of Nonlinear Measures for the Detection of Cardiac Autonomic Neuropathy from Heart Rate Variability

    Directory of Open Access Journals (Sweden)

    David Cornforth

    2015-03-01

    Full Text Available In this work we compare three multiscale measures for their ability to discriminate between participants having cardiac autonomic neuropathy (CAN and aged controls. CAN is a disease that involves nerve damage leading to an abnormal control of heart rate, so one would expect disease progression to manifest in changes to heart rate variability (HRV. We applied multiscale entropy (MSE, multi fractal detrended fluctuation analysis (MFDFA, and Renyi entropy (RE to recorded datasets of RR intervals. The latter measure provided the best separation (lowest p-value in Mann–Whitney tests between classes of participants having CAN, early CAN or no CAN (controls. This comparison suggests the efficacy of RE as a measure for diagnosis of CAN and its progression, when compared to the other multiscale measures.

  15. Paradoxical response to an emotional task: trait characteristics and heart-rate dynamics.

    Science.gov (United States)

    Balocchi, Rita; Varanini, Maurizio; Paoletti, Giulia; Mecacci, Giulio; Santarcangelo, Enrica 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 detrended fluctuation analysis (DFA). These indices were studied as a function of a few individual characteristics: hypnotizability, gender, absorption, anxiety, and the activity of the behavioral inhibition and activation systems (BIS/BAS). Results showed that (a) the subjective experience of responsiveness is associated with the activity of the behavioral inhibition system and (b) a few RQA and DFA indices are able to capture the influence of cognitive-emotional traits, including hypnotizability, on the responsiveness to the threatening task. PMID:25719521

  16. Ivabradine Prevents Heart Rate Acceleration in Patients with Chronic Obstructive Pulmonary Disease and Coronary Heart Disease after Salbutamol Inhalation

    Directory of Open Access Journals (Sweden)

    Uta C. Hoppe

    2012-04-01

    Full Text Available Accelerated sinus rhythm is an important side effect of inhaled salbutamol which is especially harmful in patients with chronic obstructive pulmonary disease (COPD and coronary heart disease (CHD. Cross-over, randomized, open label study design. 20 patients (18 males and two females with COPD stage II–IV and comorbide CHD NYHA class I–III were included. Spirometry with 400 mg salbutamol inhalation was performed at two consecutive days of the study. Patients in group I were prescribed 5 mg ivabradine per os 3 h before salbutamol inhalation solely on the first day of the study and patients of group II received 5 mg ivabradine only on the second day of the study. Salbutamol caused a significant increase of HR by 5.5 bpm (95% CI 0.8; 10.2, p < 0.03. After ivabradine ingestion salbutamol did not change HR significantly by ?2.4 bpm (?7.0; 2.3, p = 0.33. The attenuation of HR elevation by ivabradine was significant, p < 0.01. Salbutamol alone increased FEV1 by 6.0% (2.7; 9.3, p < 0.01. This effect was not impaired by ivabradine (FEV1 increase by 7.7% (2.8; 12.6, p < 0.01 versus baseline, p = 0.5 versus no ivabradine. Ivabradine 5 mg per os prevents heart rate acceleration after inhalation of 400 mg salbutamol. Ivabradine has no impact on lung function in patients with moderate-to-very-severe COPD and CHD comorbidity.

  17. Comparison of O2 saturation, heart and respiratory rate following injection of vasoconstrictor containing anesthetic (lidocaine 2% and without vasoconstrictor anesthetic (Mepivacaine

    Directory of Open Access Journals (Sweden)

    Bayat M.

    2005-07-01

    Full Text Available Background and Aim: Along with higher usage of dental local anesthesia with risks to people health together with their positive role, the important goal of dentistry, patients’ health, has been stressed repeatedly nowadays. This study was conducted to compare O2 saturation, respiratory rate and heart rate of patients following injection of anesthetic containing vasoconstrictor (lidocaine 2% and without vasoconstrictor (Mepivacaine. Materials and Methods: This experimental study was conducted on 32 healthy humans (16 females and 16 males with 25-50 years age range and no history of drug usage. Cases were classified into two matched groups. O2 saturation, heart and respiratory rate were recorded before extraction of a mandibular posterior tooth. In the first group, 3.6 ml lidocaine 2% with 1:80,000 epinephrine and in the second group Mepivacaine 3% was injected, using inferior alveolar dental nerve block with aspiration. Variables were measured and recorded. Tooth extraction was performed and the mentioned variables were recorded again. Data were analyzed with SPSS software using t and Paired t-test with P<0.05 as the limit of significance. Results: After injection of lidocaine, the heart rate was increased (12.25±1.75 bpm, and the time to reach the maximum rate was 64.75±11.26 seconds. After extraction of tooth, heart rate in both groups was increased not considering the type of injection. Conclusion: The study showed that the injection of lidocaine (containing epinephrine in patients without contraindication has no risk. Also, possible increase in heart rate is not risky and is not associated with O2 saturation decrease and respiratory interruption.

  18. The effects of cigarette smoking on aerobic and anaerobic capacity and heart rate variability among female university students

    Directory of Open Access Journals (Sweden)

    Lee CL

    2013-10-01

    Full Text Available Chia-Lun Lee,1 Wen-Dien Chang21Physical Education Section for General Education, National Sun Yat-sen University, Kaohsiung, Taiwan; 2Department of Sports Medicine, China Medical University, Taichung, TaiwanAim: In this study, the effects of cigarette smoking on maximal aerobic capacity, anaerobic capacity, and heart rate variability among female university students were investigated.Materials and methods: Twelve smokers and 21 nonsmokers participated in this study. All participants performed an intermittent sprint test (IST and a 20 m shuttle run test to measure their anaerobic capacity and maximal aerobic capacity. The IST was comprised of 6 × 10-second sprints with a 60-second active recovery between each sprint. Heart rate variability was recorded while the participants were in a supine position 20 minutes before and 30 minutes after the IST.Results: The total work, peak power, and heart rate of the smokers and nonsmokers did not differ significantly. However, the smokers’ average power declined significantly during sprints 4 to 6 (smokers versus nonsmokers, respectively: 95% confidence interval =6.2–7.2 joule/kg versus 6.8–7.6 joule/kg; P<0.05, and their fatigue index increased (smokers versus nonsmokers, respectively: 35.8% ± 2.3% versus 24.5% ± 1.76%; P<0.05 during the IST. The maximal oxygen uptake of nonsmokers was significantly higher than that of the smokers (P<0.05. The standard deviation of the normal to normal intervals and the root mean square successive difference did not differ significantly between nonsmokers and smokers. However, the nonsmokers exhibited a significantly higher normalized high frequency (HF, and significantly lower normalized low frequency (LF, LF/HF ratio, and natural logarithm of the LF/HF when compared with those of the smokers (P<0.05.Conclusion: Smoking may increase female smokers’ exercise fatigue and decrease their average performance during an IST, while reducing their maximal aerobic capacity. Furthermore, smoking reduces parasympathetic nerve activity and activates sympathetic cardiac control.Keywords: exercise test, exercise tolerance, heart rate, physical endurance, vital signs

  19. Is meditation always relaxing? Investigating heart rate, heart rate variability, experienced effort and likeability during training of three types of meditation.

    Science.gov (United States)

    Lumma, Anna-Lena; Kok, Bethany E; Singer, Tania

    2015-07-01

    Meditation is often associated with a relaxed state of the body. However, meditation can also be regarded as a type of mental task and training, associated with mental effort and physiological arousal. The cardiovascular effects of meditation may vary depending on the type of meditation, degree of mental effort, and amount of training. In the current study we assessed heart rate (HR), high-frequency heart rate variability (HF-HRV) and subjective ratings of effort and likeability during three types of meditation varying in their cognitive and attentional requirements, namely breathing meditation, loving-kindness meditation and observing-thoughts meditation. In the context of the ReSource project, a one-year longitudinal mental training study, participants practiced each meditation exercise on a daily basis for 3months. As expected HR and effort were higher during loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. With training over time HR and likeability increased, while HF-HRV and the subjective experience of effort decreased. The increase in HR and decrease in HF-HRV over training was higher for loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. In contrast to implicit beliefs that meditation is always relaxing and associated with low arousal, the current results show that core meditations aiming at improving compassion and meta-cognitive skills require effort and are associated with physiological arousal compared to breathing meditation. Overall these findings can be useful in making more specific suggestions about which type of meditation is most adaptive for a given context and population. PMID:25937346

  20. Effect of Training Mode on Post-Exercise Heart Rate Recovery of Trained Cyclists

    OpenAIRE

    McDonald, Kelia G.; Grote, Silvie; Shoepe, Todd C.

    2014-01-01

    The sympathetic nervous system dominates the regulation of body functions during exercise. Therefore after exercise, the sympathetic nervous system withdraws and the parasympathetic nervous system helps the body return to a resting state. In the examination of this relationship, the purpose of this study was to compare recovery heart rates (HR) of anaerobically versus aerobically trained cyclists. With all values given as means ± SD, anaerobically trained track cyclists (n=10, age=25.9 ± 6....

  1. Heart rate and estimated energy expenditure of flapping and gliding in black-browed albatrosses

    OpenAIRE

    Sakamoto, K. Q.; Takahashi, A.; Iwata, T; Yamamoto, T.; Yamamoto, M; Trathan, P. N.

    2013-01-01

    Albatrosses are known to expend only a small amount of energy during flight. The low energy cost of albatross flight has been attributed to energy-efficient gliding (soaring) with sporadic flapping, although little is known about how much time and energy albatrosses expend in flapping versus gliding during cruising flight. Here, we examined the heart rates (used as an instantaneous index of energy expenditure) and flapping activities of free-ranging black-browed albatrosses (Thalassarche mela...

  2. Heart rate variability on antihypertensive drugs in black patients living in sub-Saharan Africa

    OpenAIRE

    Osakwe, Chukwunomso E.; Jacobs, Lotte; Anisiuba, Benedict C.; Ndiaye, Mouhamado B; Lemogoum, Daniel; Ijoma, Chinwuba K; Kamdem, Marius M; Thijs, Lutgarde; Boombhi, Hilaire J.; Kaptue, Joseph; Kolo, Philip M.; Mipinda, Jean B; Odili, Augustine N; Ezeala-Adikaibe, Birinus; Kingue, Samuel

    2013-01-01

    Background. Compared with Caucasians, African Americans have lower heart rate variability (HRV) in the high-frequency domain, but there are no studies in Blacks born and living in Africa. Methods. In the Newer versus Older Antihypertensive agents in African Hypertensive patients trial (NCT01030458), patients (30-69 years) with uncomplicated hypertension (140-179/90-109 mmHg) were randomized to single-pill combinations of bisoprolol/hydrochlorothiazide (R) or amlodipine/valsartan (E). 72 R and...

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

    OpenAIRE

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

    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) ...

  4. Daytime stress, shoulder/neck-pain, and the relation to nocturnal heart rate variability

    OpenAIRE

    Davidsen, Roar Oskar

    2011-01-01

    Stress and musculoskeletal pain (MSP) may affect the regulation of the autonomic nervous system. Earlier studies have revealed that subjects with MSP show reduced heart rate variability (HRV) during sleep indicating an increased sympathetic drive at rest. However, it is unclear whether daytime exposures, such as work stress, stress in leisure, and daytime MSP, affect nocturnal HRV. The aim of this study was therefore to investigate the possible association between daytime stress, shoulder/nec...

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

    OpenAIRE

    LaísTonello; AnthonyLeicht

    2014-01-01

    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) o...

  6. Reduced heart rate responding to trauma reliving in trauma survivors with PTSD: correlates and consequences.

    OpenAIRE

    Halligan, Sl; Michael, T.; Wilhelm, Fh; Clark, Dm; Ehlers, A.

    2006-01-01

    The authors investigated whether heart rate (HR) responses to voluntary recall of trauma memories (a) are related to posttraumatic stress disorder (PTSD), and (b) predict recovery 6 months later. Sixty-two assault survivors completed a recall task modeled on imaginal reliving in the initial weeks postassault. Possible cognitive modulators of HR responsivity were assessed; dissociation, rumination, trauma memory disorganization. Individuals with PTSD showed a reduced HR response to reliving co...

  7. Heart rate responses to standardized trauma-related pictures in acute posttraumatic stress disorder

    OpenAIRE

    Ehlers, A.; Suendermann, O.; Boellinghaus, I.; Vossbeck-elsebusch, A.; Gamer, M.; Briddon, E.; Martin, Mw; Glucksman, E.

    2010-01-01

    Physiological responses to trauma reminders are one of the core symptoms of posttraumatic stress disorder (PTSD). Nevertheless, screening measures for PTSD largely rely on symptom self-reports. It has been suggested that psychophysiological assessments may be useful in identifying trauma survivors with PTSD (Orr and Roth, 2000). This study investigated whether heart rate (HR) responses to standardized trauma-related pictures distinguish between trauma survivors with and without acute PTSD. Su...

  8. Heart rate variability in a patient after percutaneous renal denervation: a case report

    OpenAIRE

    Baksh, Taufiq M.; Bidikar, Mukta P.

    2013-01-01

    The overactivity of sympathetic component of autonomic nervous system is implicated in the genesis and progression of hypertension. We report the heart rate variability (HRV) of a patient after renal denervation for treatment of medically resistant hypertension. Catheter based renal denervation done for treatment of resistant hypertension reduces blood pressure by reducing the central sympathetic drive. In the present study we found a significant decrease in low frequency component of HRV in ...

  9. A novel technique for fetal heart rate estimation from Doppler ultrasound signal

    OpenAIRE

    Jezewski Janusz; Roj Dawid; Wrobel Janusz; Horoba Krzysztof

    2011-01-01

    Abstract Background The currently used fetal monitoring instrumentation that is based on Doppler ultrasound technique provides the fetal heart rate (FHR) signal with limited accuracy. It is particularly noticeable as significant decrease of clinically important feature - the variability of FHR signal. The aim of our work was to develop a novel efficient technique for processing of the ultrasound signal, which could estimate the cardiac cycle duration with accuracy comparable to a direct elect...

  10. A Rabbit Ventricular Action Potential Model Replicating Cardiac Dynamics at Rapid Heart Rates

    OpenAIRE

    Mahajan, Aman; Shiferaw, Yohannes; Sato, Daisuke; Baher, Ali; Olcese, Riccardo; Xie, Lai-Hua; Yang, Ming-Jim; CHEN, PENG-SHENG; Juan G Restrepo; Karma, Alain; Garfinkel, Alan; Qu, Zhilin; Weiss, James N.

    2008-01-01

    Mathematical modeling of the cardiac action potential has proven to be a powerful tool for illuminating various aspects of cardiac function, including cardiac arrhythmias. However, no currently available detailed action potential model accurately reproduces the dynamics of the cardiac action potential and intracellular calcium (Cai) cycling at rapid heart rates relevant to ventricular tachycardia and fibrillation. The aim of this study was to develop such a model. Using an existing rabbit ven...

  11. 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.

  12. Peculiarities of the autonomic balance assessed through heart rate variability analysis in sportsmen and nonsportsmen

    OpenAIRE

    Barak Oto F.; Glaza?ev Oleg S.; Dudnik Helena N.; Korobeinikova Irina I.; Klašnja Aleksandar V.; Gruji? Nikola G.

    2008-01-01

    A comparative study was used to analyze the difference in autonomic balance assessed by time and frequency domain parameters of heart rate variability (HRV) between students athletes and non-sportsmen. Five-minute digital ECG trays were recorded in 21 students - athletes, 10 basketball players recruited from first league clubs of No- vi Sad and the Serbian representatives and 11 rowers from the Novi Sad rowing club 'Danubius'. The control group was formed by 15 non-sportsmen, students of the ...

  13. Heart rate variability in patients with idiopathic Parkinson's disease with and without obstructive sleep apnea syndrome

    OpenAIRE

    Valko, P O; Hauser, S; Werth, E; Waldvogel, D; Baumann, C R

    2012-01-01

    BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with repeated apnea-induced sympathetic surges leading to specific alterations of the power spectrum of heart rate variability (HRV). Sympathetic dysfunction evolves early in idiopathic Parkinson's disease (PD), but the consequences on cardiac autonomic response to OSAS have not been studied so far in PD patients. METHODS: Sixty-two patients with PD (35 without OSAS (PD-wo), 27 with OSAS (PD-OSAS)) and 62 age-matched control...

  14. Effects of Swedish Massage Therapy on Blood Pressure, Heart Rate, and Inflammatory Markers in Hypertensive Women

    OpenAIRE

    At, Izreen Supa Amp X.; Zaiton Zakaria; Oteh Maskon; Amilia Aminuddin; Nor Anita Megat Mohd Nordin

    2013-01-01

    Swedish Massage Therapy (SMT) is known for its therapeutic relaxation effects. Hypertension is associated with stress and elevated endothelial inflammatory markers. This randomized control trial measured the effects of whole body SMT (massage group) or resting (control group) an hour weekly for four weeks on hypertensive women. Blood pressure (BP) and heart rate (HR) were measured before and after each intervention and endothelial inflammatory markers: vascular endothelial adhesion molecules ...

  15. Enhancement of Frequency Domain Indices of Heart Rate Variability by Cholinergic Stimulation with Pyridostigmine Bromide

    OpenAIRE

    Zarei, Ali Asghar; Foroutan, Seyyed Abbas; Foroutan, Seyyed Mohsen; Erfanian Omidvar, Abbas

    2011-01-01

    Pyridostigmine bromide (PB) is a reversible cholinesterase inhibitor. The aim of this study was to determine the effect of orally administration of single dose sustained-released tablet of pyridostigmine bromide (PBSR) on the frequency domain indices of heart rate variability (HRV). Thirty-two healthy young men were participated in this study. They were divided into 2 groups; the pyridostigmine group (n = 22) and the placebo group (n = 10). Electrocardiogram (ECG) was recorded at 10, 30, 60, ...

  16. Modeling autonomic regulation of cardiac function and heart rate variability in human endotoxemia

    OpenAIRE

    Scheff, Jeremy D.; Mavroudis, Panteleimon D.; Calvano, Steven E.; Lowry, Stephen F.; Androulakis, Ioannis P.

    2011-01-01

    Heart rate variability (HRV), the quantification of beat-to-beat variability, has been studied as a potential prognostic marker in inflammatory diseases such as sepsis. HRV normally reflects significant levels of variability in homeostasis, which can be lost under stress. Much effort has been placed in interpreting HRV from the perspective of quantitatively understanding how stressors alter HRV dynamics, but the molecular and cellular mechanisms that give rise to both homeostatic HRV and chan...

  17. Individual differences in resting heart rate variability and cognitive control in posttraumatic stress disorder

    OpenAIRE

    BrandonLeeGillie

    2014-01-01

    Post-traumatic stress disorder (PTSD) is characterized by deficits in cognitive functioning, particularly cognitive control. Moreover, these deficits are thought to play a critical role in the etiology and maintenance of core PTSD symptoms such as intrusive thoughts and memories. However, the psychophysiological concomitants of cognitive control remain largely unexamined. In this article, we suggest that individual differences in heart rate variability (HRV), a physiological index of self-re...

  18. Association between heart rate variability and fluctuations in resting-state functional connectivity

    OpenAIRE

    Chang, Catie; Metzger, Coraline D.; Glover, Gary H.; Duyn, Jeff H.; Heinze, Hans-jochen; Walter, Martin

    2012-01-01

    Functional connectivity has been observed to fluctuate across the course of a resting state scan, though the origins and functional relevance of this phenomenon remain to be shown. The present study explores the link between endogenous dynamics of functional connectivity and autonomic state in an eyes-closed resting condition. Using a sliding window analysis on resting state fMRI data from 35 young, healthy male subjects, we examined how heart rate variability (HRV) covaries with temporal cha...

  19. Resting heart rate as a low tech predictor of coronary events in women: prospective cohort study

    OpenAIRE

    Hsia, Judith; Larson, Joseph C.; Ockene, Judith K.; Sarto, Gloria E.; Allison, Matthew A.; Hendrix, Susan L.; Robinson, Jennifer G.; Lacroix, Andrea Z.; Manson, Joann Elisabeth

    2009-01-01

    Objective: To evaluate resting heart rate as an independent predictor of cardiovascular risk in women. Design: Prospective cohort study. Setting: The Women’s Health Initiative was undertaken at 40 research clinics in the United States. Participants 129?135 postmenopausal women. Main outcome: measure Clinical cardiovascular events. Results: During a mean of 7.8 (SD 1.6) years of follow up, 2281 women were identified with myocardial infarction or coronary death and 1877 with stroke. We eval...

  20. Measures of heart rate variability in women following a meditation technique

    OpenAIRE

    An Hyorim; Kulkarni Ravi; Nagarathna R; Nagendra H

    2010-01-01

    Certain time domain, frequency domain and a nonlinear measure of heart rate variability are studied in women following a meditative practice called cyclic meditation. The nonlinear measure studied is the sampling entropy. We show that there is an increase in the sampling entropy in the meditative group as compared to the control group. The time domain measure called pNNx is shown to be useful in distinguishing between the meditative state and a normal resting state.

  1. Effect of meal content on heart rate variability and cardiovascular reactivity to mental stress

    OpenAIRE

    Sauder, Katherine A.; Johnston, Elyse R.; Skulas-ray, Ann C.; Campbell, Tavis S.; West, Sheila G.

    2012-01-01

    Little is known about transient effects of foods and nutrients on reactivity to mental stress. In a randomized crossover study of healthy adults (n = 20), we measured heart rate variability (respiratory sinus arrhythmia), blood pressure, and other hemodynamic variables after three test meals varying in type and amount of fat. Measurements were collected at rest and during speech and cold pressor tasks. There were significant post-meal changes in resting diastolic blood pressure (?4%), cardi...

  2. Relationship of Basal Heart Rate Variability to in Vivo Cytokine Responses Following Endotoxin

    OpenAIRE

    Jan, Badar U.; Coyle, Susette M.; Macor, Marie A.; Reddell, Michael; Calvano, Steve E.; Lowry, Stephen F.

    2010-01-01

    Autonomic inputs from the sympathetic and parasympathetic nervous systems, as measured by heart rate variability (HRV), have been reported to correlate to the severity injury and responses to infectious challenge among critically-ill patients. In addition, parasympathetic/vagal activity has been shown experimentally to exert anti-inflammatory effects via attenuation of splanchnic tissue TNF? production. We sought to define the influence of gender on HRV responses to in vivo endotoxin challen...

  3. Relationship between Heart Rate Variability, Interleukin-6, and Soluble Tissue Factor in Healthy Subjects

    OpenAIRE

    Von Ka?nel, Roland; Nelesen, Richard A.; Mills, Paul J.; Ziegler, Michael G.; Dimsdale, Joel E.

    2007-01-01

    Decreased heart rate variability (HRV) has been associated with an increased risk of atherosclerosis. We hypothesized that a decrease in frequency domains of resting HRV would be associated with elevated plasma levels of interleukin (IL)-6 and soluble tissue factor (sTF) both previously shown to prospectively predict atherothrombotic events in healthy subjects. Subjects were 102 healthy and unmedicated black and white middle-aged men and women. We determined IL-6 and sTF antigen in plasma and...

  4. Resting heart rate as a predictor of metabolic dysfunctions in obese children and adolescents

    OpenAIRE

    Freitas Júnior Ismael F; Monteiro Paula A; Silveira Loreana S; Cayres Suziane U; Antunes Bárbara M; Bastos Karolynne N; Codogno Jamile S; Sabino João Paulo J; Fernandes Rômulo A

    2012-01-01

    Abstract Background Recent studies have identified that a higher resting heart rate (RHR) is associated with elevated blood pressure, independent of body fatness, age and ethnicity. However, it is still unclear whether RHR can also be applied as a screening for other risk factors, such as hyperglycemia and dyslipidemia. Thus, the purpose of the presented study was to analyze the association between RHR, lipid profile and fasting glucose in obese children and adolescents. Methods The sample wa...

  5. ‘Fire of Life’ analysis of heart rate variability during alpine skiing in Austria

    OpenAIRE

    Gerhard Litscher; Daniela Litscher

    2010-01-01

    Background: Skiing is a very popular sport in Austria. Nevertheless, there is little information concerning online monitoring of bio-signals during alpine skiing in the mountains. Within the last years innovative scientific monitoring tools for evaluating features of neurocardial fitness have been developed. Aims: The goal of this study was to demonstrate the new ‘Fire of Life’ heart rate variability analysis for the first time during alpine skiing. Volunteers and Methods: Continuous elec...

  6. The influence of physical exertion on basic hematological parameters values and heart rate in trotters

    Directory of Open Access Journals (Sweden)

    Slijep?evi? Dajana

    2014-01-01

    Full Text Available One of very important prerequisites for achieving good results in races, in addition to genetic predisposition, quality training and good health, are optimal values for number of erythrocytes, concentration of haemoglobin and hematocrit, of which depends efficient oxygen supply of muscles during great efforts. The stated values, along with data on heart rate, are useful indicators of the degree of horse fitness and readiness for horse race. The influence of physical exertion on the values of basic hematological parameters as well as on heart rate, was investigated on 6 trotters, in training at the Belgrade racetrack (one head of Italian trotter, male, 3 years old; 3 heads of American trotter, male, 3,4 and 6 years old and two heads of Serbian trotter, female, 4 and 5 years old. The blood samples for hematological tests were taken by punction of jugular vein in resting phase - immediately before the commencement of work, after light trot warming for 3000 m and fast trot for 1000 m, with 30 minutes rest between the two runnings. The heart rate was monitored continuously by radio telemetry cardiometer, from the moment they were taken from their boxes and harnessing to the completion of work. The obtained results confirm the relationship between the rise of heart rate and hematocrit values: maximal hematocrit values were determined after the first running (0.49±0.05, in regard to 0.42±0.03 in resting phase, but 30 minutes after the second running there was a slight drop of hematocrit values (0.46±0.04. The blood samples in both cases were taken after fast trot during which there were recorded maximal pulse values, so in the moment of sampling the pulse lowered close to the values in resting - after the first running from 192.23±19.66, and after the second from 180.33±17.22 to 40.67±5.76.

  7. Heart Rate Monitoring as an Easy Way to Increase Engagement in Human-Agent Interaction

    OpenAIRE

    Frey, Je?re?my

    2014-01-01

    Physiological sensors are gaining the attention of manufacturers and users. As denoted by devices such as smartwatches or the newly released Kinect 2 -- which can covertly measure heartbeats -- or by the popularity of smartphone apps that track heart rate during fitness activities. Soon, physiological monitoring could become widely accessible and transparent to users. We demonstrate how one could take advantage of this situation to increase users' engagement and enhance user...

  8. Pilot study employing heart rate variability biofeedback training to decrease anxiety in patients with eating disorders

    OpenAIRE

    Scolnick, Barbara; Mostofsky, David I; Keane, Robert J

    2014-01-01

    Heart rate variability (HRV) biofeedback, a technique which encourages slow meditative breathing, was offered to 25 in-patients with various eating disorder diagnoses-anorexia nervosa, bulimia nervosa and binge eating disorder. We found that this modality had no serious side effects, and was subjectively useful to most participants. An enhanced ability to generate highly coherent HRV patterns in patients with recent onset anorexia nervosa was observed.

  9. Heart Rate Tracking using Wrist-Type Photoplethysmographic (PPG) Signals during Physical Exercise with Simultaneous Accelerometry

    OpenAIRE

    Mashhadi, Mahdi Boloursaz; Asadi, Ehsan; Eskandari, Mohsen; Kiani, Shahrzad; Marvasti, Farrokh

    2015-01-01

    This paper considers the problem of heart rate tracking during intensive physical exercise using simultaneous 2 channel photoplethysmographic (PPG) and 3 dimensional (3D) acceleration signals recorded from wrist. This is a challenging problem because the PPG signals recorded from wrist during exercise are contaminated by strong Motion Artifacts (MAs). In this work, a novel algorithm is proposed which consists of two main steps of MA Cancellation and Spectral Analysis. The MA...

  10. Naturalistic monitoring of the affect-heart rate relationship : a day reconstruction study

    OpenAIRE

    Daly, Michael; Delaney, Liam; Harmon, Colm; Doran, Peter; Maclachlan, Malcolm

    2009-01-01

    Objective: Prospective studies have linked both negative affective states and trait neuroticism with hypertension, cardiovascular disease, and mortality. However, identifying how fluctuations in cardiovascular activity in day-to-day settings are related to changes in affect and stable personality characteristics has remained a methodological and logistical challenge. Design: In the present study, we tested the association between affect, affect variability, personality and heart rate (H...

  11. Heart Rate Responses and Training Load During Nonspecific and Specific Aerobic Training in Adolescent Taekwondo Athletes

    OpenAIRE

    Haddad, Monoem; Chaouachi, Anis; Wong, Del P.; Castagna, Carlo; Chamari, Karim

    2011-01-01

    The efficacy of replacing generic running with Taekwondo (TKD) specific technical skills during interval training at an intensity corresponding to 90–95% of maximum heart rate (HRmax) has not yet been demonstrated. Therefore, the purpose of this study was to compare the HR responses and perceived exertion between controlled running and high-intensity TKD technical interval training in adolescent TKD athletes. Eighteen adolescent, male TKD athletes performed short-duration interval running a...

  12. A Body Shape Index and Heart Rate Variability in Healthy Indians with Low Body Mass Index

    OpenAIRE

    Sharma Sowmya; Tinku Thomas; Ankalmadagu Venkatsubbareddy Bharathi; Sambashivaiah Sucharita

    2014-01-01

    Background. One third of Indian population is said to be suffering from chronic energy deficiency (CED), with increased risk of developing chronic diseases. A new anthropometric measure called A Body Shape Index (ABSI) is said to be a better index in predicting risks for premature mortality. ABSI is also in part said to be a surrogate of visceral fat. Objective. The present study aimed to explore the association between indices of HRV (heart rate variability), BMI, WC, and ABSI in healthy Ind...

  13. ECG signal analysis for detection of Heart Rate and Ischemic Episodes

    Directory of Open Access Journals (Sweden)

    Goutam Kumar Sahoo, Samit Ari, Sarat Kumar Patra

    2013-03-01

    Full Text Available Electrocardiogram (ECG is generally used fordiagnosis ofcardiovascularabnormalitiesanddisorders.Anefficient method for analysingtheECG signal towards the detection ofheartrate(HRandischemic episodesfollows mainly fivestages:pre-processing, feature extraction,heart ratedetection,beat classification and ischemicepisoderecognition.Theheart rate is calculatedusing theextracted featuresoftheECG signal. Thecalculated HRvaluecan beanalysedforthedetectionofvariouscardiovascularabnormalities.Theabilityof the method wasvalidatedonEuropean ST-T database.Theperformance ofischemic episode detectionshows88.08% sensitivity(Se and 92.42% positive predictive accuracy (PPA.

  14. Pilot study employing heart rate variability biofeedback training to decrease anxiety in patients with eating disorders.

    Science.gov (United States)

    Scolnick, Barbara; Mostofsky, David I; Keane, Robert J

    2014-01-01

    Heart rate variability (HRV) biofeedback, a technique which encourages slow meditative breathing, was offered to 25 in-patients with various eating disorder diagnoses-anorexia nervosa, bulimia nervosa and binge eating disorder. We found that this modality had no serious side effects, and was subjectively useful to most participants. An enhanced ability to generate highly coherent HRV patterns in patients with recent onset anorexia nervosa was observed. PMID:24917934

  15. Role of editing of R-R intervals in the analysis of heart rate variability

    OpenAIRE

    MirjaPeltola

    2012-01-01

    This paper reviews the methods used for editing of the R–R interval time series and how this editing can influence the results of heart rate (HR) variability analyses. Measurement of HR variability from short and long-term electrocardiographic (ECG) recordings is a non-invasive method for evaluating cardiac autonomic regulation. HR variability provides information about the sympathetic-parasympathetic autonomic balance. One important clinical application is the measurement of HR variability...

  16. Cardiac Sympathetic Activity Assessed by Heart Rate Variability Indicates Myocardial Ischemia on Cold Exposure in Diabetes

    OpenAIRE

    Sasaki, Keita; Matsushita, Shonosuke; Sato, Fujio; Tokunaga, Chiho; Hyodo, Kazuyuki; Sakakibara, Yuzuru

    2013-01-01

    Measurement of heart rate variability (HRV) is a non-invasive technique that can be used to investigate functioning of the autonomic nervous system, especially the balance between sympathetic and vagal activities. It is reported that dilatation of coronary microcirculation by augmentation of sympathetic nerve activity (SNA) caused by cold exposure was impaired in diabetes. The question of whether or not SNA in HRV could respond to coronary ischemia was evaluated by cold exposure in diabetic r...

  17. Monitoring Fetal Heart Rate during Pregnancy: Contributions from Advanced Signal Processing and Wearable Technology

    OpenAIRE

    Signorini, Maria G.; Andrea Fanelli; Giovanni Magenes

    2014-01-01

    Monitoring procedures are the basis to evaluate the clinical state of patients and to assess changes in their conditions, thus providing necessary interventions in time. Both these two objectives can be achieved by integrating technological development with methodological tools, thus allowing accurate classification and extraction of useful diagnostic information. The paper is focused on monitoring procedures applied to fetal heart rate variability (FHRV) signals, collected during pregnan...

  18. Identifying diabetic patients with cardiac autonomic neuropathy by heart rate complexity analysis

    OpenAIRE

    Palaniswami Marimuthu; Jelinek Herbert F; Khandoker Ahsan H

    2009-01-01

    Abstract Background Cardiac autonomic neuropathy (CAN) in diabetes has been called a "silent killer", because so few patients realize that they suffer from it, and yet its effect can be lethal. Early sub clinical detection of CAN and intervention are of prime importance for risk stratification in preventing sudden death due to silent myocardial infarction. This study presents the usefulness of heart rate variability (HRV) and complexity analyses from short term ECG recordings as a screening t...

  19. Changes in Heart Rate in Patients with a Pacemaker do not Affect Cardiac Output.

    Czech Academy of Sciences Publication Activity Database

    Vondra, Vlastimil; Soukup, L.; Jurák, Pavel; Halámek, Josef; Viš?or, Ivo; Lipoldová, J.; Leinveber, Pavel

    Piscataway : IEEE, 2012, s. 511. ISBN 978-1-4244-4119-8. [EMBC 2012. Annual International Conference of the IEEE Engineering in Medicine and Biology Society /34./. San Diego (US), 28.08.2012-01.09.2012] R&D Projects: GA MŠk ME09050; GA MŠk ED0017/01/01; GA ?R GAP102/12/2034 Institutional support: RVO:68081731 Keywords : Pacemaker * Changes in Heart Rate * Cardiac Output Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  20. Personal Exposure to Submicrometer Particles and Heart Rate Variability in Human Subjects

    OpenAIRE

    Chan, Chang-chuan; Chuang, Kai-jen; Shiao, Guang-ming; Lin, Lian-yu

    2004-01-01

    We conducted a study on two panels of human subjects—9 young adults and 10 elderly patients with lung function impairments—to evaluate whether submicrometer particulate air pollution was associated with heart rate variability (HRV). We measured these subjects’ electrocardiography and personal exposure to number concentrations of submicrometer particles with a size range of 0.02–1 ?m (NC0.02–1) continuously during daytime periods. We used linear mixed-effects models to estimate the ...

  1. Ambient Temperature, Air Pollution, and Heart Rate Variability in an Aging Population

    OpenAIRE

    Ren, Cizao; O'Neill, Marie S; Park, Sung Kyun; Sparrow, David; Vokonas, Pantel; Schwartz, Joel

    2011-01-01

    Studies show that ambient temperature and air pollution are associated with cardiovascular disease and that they may interact to affect cardiovascular events. However, few epidemiologic studies have examined mechanisms through which ambient temperature may influence cardiovascular function. The authors examined whether temperature was associated with heart rate variability (HRV) in a Boston, Massachusetts, study population and whether such associations were modified by ambient air pollution c...

  2. Neurohumoral mechanisms associated with orthostasis: Reaffirmation of the significant contribution of the heart rate response

    Directory of Open Access Journals (Sweden)

    VictorAConvertino

    2014-06-01

    Full Text Available The inability to compensate for acute central hypovolemia underlies the clinical development of orthostatic hypotension and instability (e.g., syncope. Although neuro-humoral control of both cardiac output and peripheral vascular resistance contributes to hemodynamic stability during orthostasis, a notion has been proposed that the failure of adequate peripheral vascular constriction rather than cardiac responses represents the primary mechanism the development of orthostatic intolerance. This review article provides an opportunity to present compelling evidence captured over the past 30 years in our laboratory to support the concept that neural-mediated tachycardia during orthostasis in healthy individuals represents a critical response to tolerating acute reduction in central blood volume in addition to, and independent of, peripheral vascular constriction. In this review paper, data are presented from experiments using graded lower body negative pressure (LBNP as a method to induce orthostatic intolerance in two experimental human models: 1 comparison of heart rate and autonomic responses in individuals with relatively high and low tolerance to LBNP; and 2 vagal and sympathetic blockade of cardiac neural control. These experiments revealed that: 1 greater elevations in heart rate are associated with higher orthostatic (LBNP tolerance; 2 higher orthostatic heart rate is associated with greater sympathetic nerve activity and withdrawal of vagally-mediated cardiac baroreflex response; and 3 nonspecific sympathetic blockade causes a pronounced reduction in heart rate and LBNP tolerance. Cardiac parasympathetic withdrawal contributes to protection against development of hypotension during the initial seconds of transition to an orthostatic challenge, while the primary mechanism by which tachycardia defends orthostatic stability in healthy subjects for extended durations is mediated predominantly through sympathetic adrenergic control.

  3. Heart Rate Variability in Association with Frequent Use of Household Sprays and Scented Products in SAPALDIA

    OpenAIRE

    Mehta, Amar Jayant; Adam, Martin; Schaffner, Emmanuel; Barthe?le?my, Jean-claude; Carballo, David; Gaspoz, Jean-michel; Rochat, Thierry; Schindler, Christian; Schwartz, Joel David; Zock, Jan-paul; Ku?nzli, Nino; Probst-hensch, Nicole

    2012-01-01

    Background: Household cleaning products are associated with adverse respiratory health outcomes, but the cardiovascular health effects are largely unknown. Objective: We determined if long-term use of household sprays and scented products at home was associated with reduced heart rate variability (HRV), a marker of autonomic cardiac dysfunction. Methods: We recorded 24-hr electrocardiograms in a cross-sectional survey of 581 Swiss adults, ? 50 years of age, who answered a detailed questionn...

  4. Attenuated Heart Rate Response is Associated with Hypocretin Deficiency in Patients with Narcolepsy.

    DEFF Research Database (Denmark)

    SØrensen, Gertrud Laura; Knudsen, Stine

    2013-01-01

    Our results show that autonomic dysfunction is part of the narcoleptic phenotype, and that hypocretin-1 deficiency is the primary predictor of this dysfunction. This finding suggests that the hypocretin system participates in the modulation of cardiovascular function at rest. CITATION: Sorensen GL; Knudsen S; Petersen ER; Kempfner J; Gammeltoft S; Sorensen HBD; Jennum P. Attenuated heart rate response is associated with hypocretin deficiency in patients with narcolepsy. SLEEP 2013;36(1):91-98.

  5. Cardiac effects of cupping: myocardial infarction, arrhythmias, heart rate and mean arterial blood pressure in the rat heart.

    Science.gov (United States)

    Shekarforoush, Shahnaz; Foadoddini, Mohsen

    2012-08-31

    This study was carried out to determine the effects of cupping on hemodynamic parameters, arrhythmias and infarct size (IS) after myocardial ischemic reperfusion injury in male rats. Rats were randomly subjected to dry or wet cupping. While dry cupping simply involved stimulation of the skin by suction, in wet cupping, scarification of the back skin was also carried out with a surgical blade and 0.5 ml blood was sucked out in each session. For ischemic reperfusion injury, rats were subjected to 30 min of left anterior descending coronary artery occlusion and 120 min of reperfusion. Our results show that cupping did not change the baseline heart rate or mean arterial blood pressure. Ischemic reperfusion injury caused an IS of 50 ± 5%, whereas dry cupping, single and repeated wet cupping significantly reduced IS to 28 ± 3%, 35 ± 3% and 22 ± 2% of area at risk, respectively. The rate of ischemic induced arrhythmias was significantly modified by wet cupping (P < 0.05). These results indicate for the first time in rats that cupping might be cardioprotective in the ischemic reperfusion injury model. PMID:23282166

  6. Exercise induced changes in lymphocyte beta adrenergic receptors correlate with peak exercise heart rates in healthy trained and sedentary human subjects

    International Nuclear Information System (INIS)

    Lymphocyte beta adrenergic receptors (lymph BAR) increase after maximal multistage treadmill exercise (TME) presumably by externalization from intracellular vesicles. Nine healthy subjects underwent symptom limited TME by the Bruce protocol. Heart rate was measured at the end of each 3 minute stage. Plasma norepinephrine (NE), plasma epinephrine (EPI) and lymph BAR were measured at rest and at peak exercise. Catecholamines were determined by high performance liquid chromatography. Lymph BAR were measured by separating cells from 25cc of whole blood across a Ficoll-Hypaque density gradient and incubating membrane preparations with 7 dilutions of I125 cyanopindolol in the presence or absence of 1?M(-) propranolol in a total assay volume of 450 ?l. BAR was standardized to Lowry-Peterson protein at rest and exercise. The relationship of maximum heart rate versus peak plasma NE, EPI and lymph BAR was analyzed by linear regression. The following conclusions were reached: (1) there is a significant correlation between exercise induced changes in lymph BAR and peak heart rate; (2) this relationship does not exist between peak plasma NE or EPI and peak heart rate

  7. Heart rate and body weight alterations in juvenile specimens of the tropical land snail Megalobulimus sanctipauli during dormancy

    Directory of Open Access Journals (Sweden)

    Rizzatti A.C.S.

    2001-01-01

    Full Text Available The time course of heart rate and body weight alterations during the natural period of dormancy were determined in active feeding and dormant juvenile specimens of Megalobulimus sanctipauli. In both groups, heart rate markedly decreased during the first 40 days of dormancy, tending to stabilize thereafter. This time period coincided with the decrease in environmental temperature during autumn-winter. At the end of the dormancy period, surviving active feeding and dormant snails showed a significant decrease in heart rate which, however, was significantly greater in the latter group. Total body weight decreased concomitantly with heart rate in dormant snails but remained constant in active feeding snails. Body hydration induced significant increases in weight and heart rate in surviving dormant snails. Feeding following hydration promoted a new significant increase in heart rate but not in weight. These results indicate that the decrease in heart rate observed in juvenile specimens of M. sanctipauli during dormancy may be due to at least three factors: 1 decrease in environmental temperature during autumn-winter, 2 starvation which leads to the depletion of endogenous fuel reserves and to a probable decrease in hemolymph nutrient levels, and 3 dehydration which leads to a probable decrease in hemolymph volume and venous return and/or to an increase in hemolymph osmolarity.

  8. Individually Coded Telemetry: a Tool for Studying Heart Rate and Behaviour in Reindeer Calves

    Directory of Open Access Journals (Sweden)

    Pudas T

    2002-09-01

    Full Text Available The aim of the study was to test the performance of a silver wire modified version of the coded telemetric heart rate monitor Polar Vantage NV™ (PVNV and to measure heart rate (HR in a group of captive reindeer calves during different behaviour. The technical performance of PVNV HR monitors was tested in cold conditions (-30°C using a pulse generator and the correlation between generated pulse and PVNV values was high (r = 0.9957. The accuracy was tested by comparing the HR obtained with the PVNV monitor with the standard ECG, and the correlation was significant (r = 0.9965. Both circadian HR and HR related to behavioural pattern were recorded. A circadian rhythm was observed in the HR in reindeer with a minimum during night and early morning hours and maximum at noon and during the afternoon, the average HR of the reindeer calves studied being 42.5 beats/min in February. The behaviour was recorded by focal individual observations and the data was synchronized with the output of the HR monitors. Running differed from all other behavioural categories in HR. Inter-individual differences were seen expressing individual responses to external and internal stimuli. The silver wire modified Polar Vantage NV™ provides a suitable and reliable tool for measuring heart rate in reindeer, also in natural conditions.

  9. Influence of exercise modality on agreement between gas exchange and heart rate variability thresholds

    Scientific Electronic Library Online (English)

    F.A., Cunha; R.A., Montenegro; A.W., Midgley; F., Vasconcellos; P.P., Soares; P., Farinatti.

    2014-08-01

    Full Text Available The main purpose of this study was to investigate the level of agreement between the gas exchange threshold (GET) and heart rate variability threshold (HRVT) during maximal cardiopulmonary exercise testing (CPET) using three different exercise modalities. A further aim was to establish whether there [...] was a 1:1 relationship between the percentage heart rate reserve (%HRR) and percentage oxygen uptake reserve ( % V ? O 2 ?R ) at intensities corresponding to GET and HRVT. Sixteen apparently healthy men 17 to 28 years of age performed three maximal CPETs (cycling, walking, and running). Mean heart rate and V ? O 2 at GET and HRVT were 16 bpm (P0.05). There was a strong relationship between GET and HRVT, with R2 ranging from 0.69 to 0.90. A 1:1 relationship between %HRR and % V ? O 2 ?R was not observed at GET and HRVT. The %HRR was higher during cycling (GET mean difference=7%; HRVT mean difference=11%; both P

  10. Endogenous vasopressin and the central control of heart rate during dynamic exercise

    Directory of Open Access Journals (Sweden)

    L.C. Michelini

    1998-09-01

    Full Text Available The present article contains a brief review on the role of vasopressinergic projections to the nucleus tractus solitarii in the genesis of reflex bradycardia and in the modulation of heart rate control during exercise. The effects of vasopressin on exercise tachycardia are discussed on the basis of both the endogenous peptide content changes and the heart rate response changes observed during running in sedentary and trained rats. Dynamic exercise caused a specific vasopressin content increase in dorsal and ventral brainstem areas. In accordance, rats pretreated with the peptide or the V1 blocker into the nucleus tractus solitarii showed a significant potentiation or a marked blunting of the exercise tachycardia, respectively, without any change in the pressure response to exercise. It is proposed that the long-descending vasopressinergic pathway to the nucleus tractus solitarii serves as one link between the two main neural controllers of circulation, i.e., the central command and feedback control mechanisms driven by the peripheral receptors. Therefore, vasopressinergic input could contribute to the adjustment of heart rate response (and cardiac output to the circulatory demand during exercise.

  11. The effects of exposure to environmental factors on Heart Rate Variability: An ecological perspective

    International Nuclear Information System (INIS)

    The impact of human exposure to environmental factors on Heart Rate Variability (HRV) was examined in the urban space of Tel-Aviv-Jaffa. Four environmental factors were investigated: thermal and social loads; CO concentrations and noise. Levels of HRV are explained mainly by subjective social stresses, noise and CO. The most interesting result is the fact that while subjective social stress and noise increase HRV, low levels of CO are reducing HRV to some extent moderating the impact of subjective social stress and noise. Beyond the poisoning effect of CO and the fact that extremely low levels of HRV associated with high dozes of CO increase risk for life, low levels of CO may have a narcotic effect, as it is measured by HRV. The effects of thermal loads on HRV are negligible probably due to the use of behavioral means in order to neutralize heat and cold effects. -- Highlights: ? The impact of human exposure to environmental factors on Heart Rate Variability (HRV) was examined. ? Previous studies measured human exposure to pollution by fixed monitoring stations. ? This study measured actual personal exposure by mini sensors. ? High level of subjective social load and noise increase HRV. ? Low levels of CO may have a narcotic effect, as it is measured by HRV. -- The research focuses on the effects of environmental factors; noise, subjective social stress, thermal load and CO on Heart Rate Variability

  12. Analysis of heart rate control to assess thermal sensitivity responses in Brazilian toads

    Scientific Electronic Library Online (English)

    J.E.S., Natali; B.T., Santos; V.H., Rodrigues; J.G., Chauí-Berlinck.

    2015-01-01

    Full Text Available In anurans, changes in ambient temperature influence body temperature and, therefore, energy consumption. These changes ultimately affect energy supply and, consequently, heart rate (HR). Typically, anurans living in different thermal environments have different thermal sensitivities, and these cann [...] ot be distinguished by changes in HR. We hypothesized that Rhinella jimi (a toad from a xeric environment that lives in a wide range of temperatures) would have a lower thermal sensitivity regarding cardiac control than R. icterica (originally from a tropical forest environment with a more restricted range of ambient temperatures). Thermal sensitivity was assessed by comparing animals housed at 15° and 25°C. Cardiac control was estimated by heart rate variability (HRV) and heart rate complexity (HRC). Differences in HRV between the two temperatures were not significant (P=0.214 for R. icterica and P=0.328 for R. jimi), whereas HRC differences were. All specimens but one R. jimi had a lower HRC at 15°C (all P

  13. Analysis of heart rate variability and possibility of its utilization in psychology and psycho-physiology

    Directory of Open Access Journals (Sweden)

    Kovaleva A.V.

    2013-03-01

    Full Text Available Indices of heart rate variability are reliable and objective indicators of autonomic nervous systemtonus (of its sympathetic and parasympathetic divisions which in its turn reflect the changes in psycho-emotional state of a person, development of stress or any kind of tension. The purpose of this article was to describethe contemporary methods of objective study of a person’s functional state by the definition of autonomic regulation of heart rate and also the review of foreign studies which discuss the possibility of utilizing this method in psychology and psychophysiology. The review describes two approaches to the analysis of heart rate variability: temporal and frequency-response analyses. The indices used for temporal analysis include average duration of RR-intervalsand percentage of couples of RR-intervals, differing in more than 50ms(?NN50. The indices of frequency-response analysis included intensity of HF component, reflecting influences of parasympathetic outflow; intensity of LF component, reflecting sympathetic influences; intensity of VLF components; correlation of LF and HF waves, reflecting vegetal balance.

  14. Portable Heart Rate Detector Based on Photoplethysmography with Android Programmable Devices for Ubiquitous Health Monitoring System

    Directory of Open Access Journals (Sweden)

    Chi Kin Lao

    2013-01-01

    Full Text Available In this paper, a miniature portable heart rate detector system is implemented by modern hardware ICs and simple sensor circuit with software executable on both PC and Android platform. The biosignal is first extracted via photoplethysmography (PPG principle into electric signal. Then a microprocessor is used to covert biosignal from analog to digital format, suitably for feeding into an RF module (nRF24L01 for RF transmission. On the receiver end, the computer and/or smart phone can analyze the data using a robust algorithm that can detect peaks of the PPG waveform, hence to calculating the heart rate. Some application software running on Windows and Android phone have been developed to display heart rate information and time domain waveform to users for health care monitoring. In the future, pure Bluetooth technology will be used for wireless personal communications instead of RF modules. At the same time, the data can be sent to computer console using existing available networks (3G, 4G, WiFi, etc. for health database logging purpose.

  15. Heart rate deflection point during incremental test in competitive agility border collies.

    Science.gov (United States)

    Radin, Lada; Beli?, Maja; Brklja?a Bottegaro, Nika; Hrasti?, Hrvoje; Torti, Marin; Vu?eti?, Vlatko; Stanin, Damir; Vrbanac, Zoran

    2015-06-01

    The aim of this study was to determine a heart rate deflection point (HRdp) in competitive agility dogs. Fourteen healthy border collies underwent progressive incremental treadmill exercise - modified Conconi test protocol. Heart rate was continuously recorded, and the HRdp was estimated using two methods: subjective and computer aided regression. Maximal heart rate (HRmax), achieved running speed at the anaerobic threshold and at the end of test were also determined. Statistical analysis showed a very high positive correlation between HRdp determined by two methods. The mean HRdp in this research corresponded to 80 % of HRmax. The wide range of individual HRdp (162-229 BPM) indicates the need of an individual approach in assessing physiological parameters. To the authors' knowledge, this is the first application of Conconi modified test for estimating anaerobic threshold in agility dogs since the standard for dogs is yet undetermined. Future studies need to detect the most appropriate and reliable technique for its determination as well as its applicability in programming of the optimal training intensity. PMID:25846949

  16. Heart Rate and QT interval Variability in Multiple Sclerosis: Evidence for Decreased Sympathetic Activity

    Directory of Open Access Journals (Sweden)

    Micahel BONNETT

    2006-12-01

    Full Text Available Decreased beat-to-beat heart rate variability (HR and increased beat-to-beat QT interval variability are associated with significant cardiovascular mortality. The aim of this study was to compare beat-to-beat HR and QT variability among patients with multiple sclerosis (MS and normal controls to investigate cardiac autonomic function. We investigated spectral measures of HR and QT interval variability in 13 patients with MS and 16 normal controls during sleep. Our results showed modest but significant decreases in HR total power (TP: 0-0.5 Hz, VLF power (very low frequency power: 0-0.04 Hz and LF power (low frequency: 0.14-0.5 Hz in patients with MS compared to normal controls. QT interval TP, VLF, LF and HF powers were all highly significantly lower (p<0.00001 in MS patients compared to normal controls. QTvi, a normalized index of QT variability corrected for mean QT interval divided by heart rate variability corrected for mean heart rate was significantly lower in MS patients. There was a significant inverse correlation between fatigue scores and QT TP, VLF and LF powers (p=0.03 to 0.01. These findings suggest a decrease in cardiac sympathetic function more than a decrease in vagal function in some patients with multiple sclerosis, and decreased sympathetic function may be related to fatigue in these patients.

  17. Integrative aspects of the relationship between stress and heart rate variability

    Directory of Open Access Journals (Sweden)

    Suelen Moraes de Lorenzo

    2013-12-01

    Full Text Available The literature indicates stress as a response of the organism to a stimulation that requires enormous efforts to adapt to the changes in the environment and the body. When an individual is subjected to stress, the autonomic nervous system is triggered, the sympathetic pathway is activated, and the parasympathetic system is suppressed, which exerts several effects on the cardiovascular system and affects heart rate variability. This research aimed to conduct a literature review to find and analyze the studies that address clearly the implications of stress on heart rate variability. The methodology employed was an active search in the databases SciELO, PubMed and Lilacs. The results were five articles, most of which suggest a relationship between stress and heart rate variability. We observed that the majority of the studies indicated a strong association between stress and cardiac autonomic activity. The stress is present in the daily activities of the population, especially in labor. The subject is vast, however, were observed in the references the effects of stress on the body making it vulnerable to diseases. Thus, this information may contribute to the aid of preventive strategies against stress and diseases of the cardiovascular system.

  18. QT Measurement and Heart Rate Correction during Hypoglycemia : Is There a Bias?

    DEFF Research Database (Denmark)

    Christensen, Toke Folke; RandlØv, Jette

    2010-01-01

    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 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 prolongation at hypoglycemia for QTcB (42(6)?ms; P <.001) and QTcF (35(6)?ms; P <.001). The MA method showed prolongation at hypoglycemia for QTcB (7(2)?ms, P <.05) but not QTcF. No difference in ECG variables between the types of insulin was observed. Discussion. The method for measuring the QT interval has a significant impact on the prolongation of QT during hypoglycemia. Heart rate correction may also influence the QT during hypoglycemia while the type of insulin is insignificant. Prolongation of QTc in this study did not reach pathologic values suggesting that QTc prolongation cannot fully explain the dead-in-bed syndrome.

  19. The Association between Neuroticism and Heart Rate Variability Is Not Fully Explained by Cardiovascular Disease and Depression

    Science.gov (United States)

    ?uki?, Iva; Bates, Timothy C.

    2015-01-01

    Neuroticism is associated with cardiovascular disease, autonomic reactivity, and depression. Here we address the extent to which neuroticism accounts for the excess heart disease risk associated with depression and test whether cardiac autonomic tone plays a role as mediator. Subjects were derived from a nationally representative sample (n = 1,255: mean age 54.5, SD = 11.5). Higher neuroticism was associated with reduced heart rate variability equally under rest and stress. The baseline structural equation model revealed significant paths from neuroticism to heart rate variability, cardiovascular disease and depression, and between depression and cardiovascular disease, controlling for age, sex, height, weight, and BMI. Dropping both the neuroticism to heart rate variability, and neuroticism to heart disease paths significantly reduced the model fit (p < .001 in each case). We conclude that neuroticism has independent associations with both autonomic reactivity and cardiovascular disease, over and above its associations with depression and other related variables. PMID:25951236

  20. Post-exercise changes in blood pressure, heart rate and rate pressure product at different exercise intensities in normotensive humans

    OpenAIRE

    Forjaz C.L.M.; Matsudaira Y.; Rodrigues F.B.; Nunes N.; Negrão C.E.

    1998-01-01

    To evaluate the effect of exercise intensity on post-exercise cardiovascular responses, 12 young normotensive subjects performed in a randomized order three cycle ergometer exercise bouts of 45 min at 30, 50 and 80% of VO2peak, and 12 subjects rested for 45 min in a non-exercise control trial. Blood pressure (BP) and heart rate (HR) were measured for 20 min prior to exercise (baseline) and at intervals of 5 to 30 (R5-30), 35 to 60 (R35-60) and 65 to 90 (R65-90) min after exercise. Systolic, m...