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Sample records for heart rate conclusion

  1. Target Heart Rate Calculator

    Science.gov (United States)

    ... My Saved Articles » My ACS » + - Text Size Target Heart Rate Calculator Compute your best workout Enter your age ... is your age? years. How to Check Your Heart Rate Right after you stop exercising, take your pulse: ...

  2. Tachycardia | Fast Heart Rate

    Science.gov (United States)

    Tachycardia | Fast Heart Rate Updated:Apr 21,2015 Tachycardia = Too fast A heart rate of more than 100 beats per minute (BPM) ... Atrial or Supraventricular tachycardia (SVT) is a fast heart rate that starts in the upper chambers of the ...

  3. Modelling Heart Rate Kinetics

    OpenAIRE

    Zakynthinaki, Maria S.

    2015-01-01

    The objective of the present study was to formulate a simple and at the same time effective mathematical model of heart rate kinetics in response to movement (exercise). Based on an existing model, a system of two coupled differential equations which give the rate of change of heart rate and the rate of change of exercise intensity is used. The modifications introduced to the existing model are justified and discussed in detail, while models of blood lactate accumulation in respect to time an...

  4. All about Heart Rate (Pulse)

    Science.gov (United States)

    All About Heart Rate (Pulse) Updated:Aug 5,2015 What should you know about your heart rate? Even if you’re not an athlete, knowledge ... Where is it and what is a normal heart rate? The best places to find your pulse are ...

  5. Heart rate response to breathing

    DEFF Research Database (Denmark)

    Mehlsen, J; Pagh, K; Nielsen, J S; Sestoft, L; Nielsen, S L

    1987-01-01

    Heart rate responses to stepwise and periodic changes in lung volume were studied in seven young healthy males. Stepwise inspiration and expiration both resulted in an increase in heart rate followed by a rapid decrease in heart rate. The fastest heart rate was reached in 1.6 +/- 0.5 s and in 3.6 +/- 1.4 s in response to inspiration and expiration, respectively (P less than 0.01). The slowest heart rate was reached in 4.8 +/- 1.0 s and in 7.6 +/- 1.9 s in response to inspiration and expiration, ...

  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. Heart rate in professional musicians

    Directory of Open Access Journals (Sweden)

    García Daniel

    2008-07-01

    Full Text Available Abstract Background Very few studies have analysed heart rate (HR with regard to music playing, and the scarce evidence available is controversial. The purpose of this study was to analyse the HR response of professional musicians during their real-work activity. Methods Sixty-two voluntary professional musicians (20 women, 42 men, whose ages ranged between 15 and 71 years old, underwent the test while playing their instruments in real life scenarios, i.e. rehearsals, practice and public concerts. The musicians carried Sport Tester PE4000 (Polar®, Finland pulsometers to record their HR. In order to compare data from differently aged subjects we calculated their Maximum Theoretical Heart Rate (MTHR. Later on we found out the MTHR percentages (%MTHR corresponding to the registered HR of each subject in different situations. The value of the MTHR for every musician was obtained by means of the 220 – age (in years formula. Results Throughout the HR recordings, we have observed that musicians present a heightened HR while playing (in soloists, mean and maximum HR were 72% and 85%MTHR, respectively. Cardiac demand is significantly higher in concerts than in rehearsals while performing the same musical piece. The HR curves corresponding to the same musician playing in repeated concerts (with the same programme were similar. Conclusion The cardiac demand of a professional instrument player is higher than previously described, much greater than what would be expected from a supposedly sedentary activity.

  8. Fetal Heart Rate Monitoring during Labor

    Science.gov (United States)

    What is fetal heart rate monitoring? Fetal heart rate monitoring is the process of checking the condition of your baby during labor and delivery ... heart rate with special equipment. Why is fetal heart rate monitoring done during labor and delivery? Fetal heart ...

  9. Blood Pressure vs. Heart Rate

    Science.gov (United States)

    ... Pressure High Blood Pressure Tools & Resources Stroke More Blood Pressure vs. Heart Rate Updated:Sep 4,2014 Blood ... was last reviewed on 08/04/2014. High Blood Pressure • Home • About High Blood Pressure (HBP) Introduction What ...

  10. 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.

  11. Dimensional analysis of heart rate variability in heart transplant recipients

    Energy Technology Data Exchange (ETDEWEB)

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

    1987-01-01

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

  12. HEART RATE VARIABILITY AND 24-HOUR MINIMUM HEART RATE

    Science.gov (United States)

    Heart rate variability (HRV) indices based on 24-hour electrocardiograph recordings have been used in clinical research studies to assess the aggregate activity of the autonomic nervous system. While 24-hour HRV is generally considered non-invasive, use in research protocols typically involves cons...

  13. Heart rate in professional musicians

    OpenAIRE

    García Daniel; Terrados Nicolás; Iñesta Claudia; Pérez José A

    2008-01-01

    Abstract Background Very few studies have analysed heart rate (HR) with regard to music playing, and the scarce evidence available is controversial. The purpose of this study was to analyse the HR response of professional musicians during their real-work activity. Methods Sixty-two voluntary professional musicians (20 women, 42 men), whose ages ranged between 15 and 71 years old, underwent the test while playing their instruments in real life scenarios, i.e. rehearsals, practice and public co...

  14. How to Take Your Heart Rate

    Science.gov (United States)

    ... effective for your body. How to Take Your Heart Rate Taking your pulse during physical activity allows you ... years) 50% (BPM) 70% (BPM) 85% (BPM) Maximum Heart Rate (BPM) 20 100 140 170 200 25 98 ...

  15. Wearable sensor for heart rate detection

    Science.gov (United States)

    Shi, Cong; Liu, Xiaohua; Kong, Lingqin; Wu, Jizhe; Liu, Ming; Dong, Liquan; Hui, Mei; Zhao, Yuejin

    2015-08-01

    In recent years heart and blood vessel diseases kill more people than everything else combined. The daily test of heart rate for the prevention and treatment of the heart head blood-vessel disease has the vital significance. In order to adapt the transformation of medical model and solve the low accuracy problem of the traditional method of heart rate measuring, we present a new method to monitor heart rate in this paper. The heart rate detection is designed for daily heart rate detection .The heart rate signal is collected by the heart rate sensor. The signal through signal processing circuits converts into sine wave and square wave in turn. And then the signal is transmitted to the computer by data collection card. Finally, we use LABVIEW and MATLAB to show the heart rate wave and calculate the heart rate. By doing contrast experiment with medical heart rate product, experimental results show that the system can realize rapidly and accurately measure the heart rate value. A measurement can be completed within 10 seconds and the error is less than 3beat/min. And the result shows that the method in this paper has a strong anti-interference ability. It can effectively suppress the movement interference. Beyond that the result is insensitive to light.

  16. Increased heteroscedasticity of heart rate in fatal heart failure

    Science.gov (United States)

    Struzik, Z. R.; Kiyono, K.; Hayano, J.; Watanabe, E.; Yamamoto, Y.

    2008-04-01

    Healthy human heart rate is known to fluctuate in a highly complex manner, displaying complexity characteristics such as those shared by physical systems at a critical state. It is, however, widely believed that chronic heart failure reduces this complexity and that heart rate data from chronic-heart-failure patients can be used for the validation of complexity measures and paradigms applicable both to heart rate and more generally to assess any system's complexity. Here, we counter the above belief, showing an increase in fluctuations and in complexity of heart rate in chronic-heart-failure patients, in particular those at risk of death. This is supported by evidence of increased non-Gaussianity and heteroscedasticity resulting from the emergence of a characteristic correlation scale in the magnitude correlation landscape.

  17. Resting heart rate, heart rate variability and functional decline in old age

    DEFF Research Database (Denmark)

    Ogliari, Giulia; Mahinrad, Simin; Stott, David J; Jukema, J Wouter; Mooijaart, Simon P; Macfarlane, Peter W; Clark, Elaine N; Kearney, Patricia M; Westendorp, Rudi G J; de Craen, Anton J M; Sabayan, Behnam

    2015-01-01

    BACKGROUND: Heart rate and heart rate variability, markers of cardiac autonomic function, have been linked with cardiovascular disease. We investigated whether heart rate and heart rate variability are associated with functional status in older adults, independent of cardiovascular disease. METHODS: We obtained data from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER). A total of 5042 participants were included in the present study, and mean followup was 3.2 years. Heart ra...

  18. Peak heart rates at extreme altitudes

    DEFF Research Database (Denmark)

    Lundby, C; Van Hall, Gerrit

    2001-01-01

    We have measured maximal heart rate during a graded maximal bicycle exercise test to exhaustion in five healthy climbers before and during an expedition to Mt. Everest. Maximal heart rates at sea level were 186 (177-204) beats/min(-1) at sea level and 170 (169-182) beats/min(-1) with acute hypoxia. After 1, 4 and 6 weeks of acclimatization to 5400 m, maximal heart rates were 155 (135-182), 158 (144-182), and 155 (140-183) beats/min(-1), respectively. Heart rates of two of the climbers were measu...

  19. Bluetooth Heart Rate Monitors For Spaceflight

    Science.gov (United States)

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

    2016-01-01

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

  20. 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.

  1. Heart Rates of Elite Synchronized Swimmers.

    Science.gov (United States)

    Gemma, Karen Erickson; Wells, Christine L.

    1987-01-01

    Heart rates were recorded by radiotelemetry in ten elite and national-class synchronized swimmers as they performed competitive figures of high degrees of difficulty. The focus was on changes in heart rates and electrocardiogram patterns for each body position, especially those requiring facial immersion and breath-holding. (Author/MT)

  2. Heart Rate and Reinforcement Sensitivity in ADHD

    Science.gov (United States)

    Luman, Marjolein; Oosterlaan, Jaap; Hyde, Christopher; van Meel, Catharina S.; Sergeant, Joseph A.

    2007-01-01

    Background: Both theoretical and clinical accounts of attention-deficit/hyperactivity disorder (ADHD) implicate a dysfunctional reinforcement system. This study investigated heart rate parameters in response to feedback associated with reward and response cost in ADHD children and controls aged 8 to 12. Methods: Heart rate responses (HRRs)…

  3. Metaiodobenzylguanidine and heart rate variability in heart failure

    International Nuclear Information System (INIS)

    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 123I-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)

  4. 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)

  5. FPGA Implementation of Heart Rate Monitoring System.

    Science.gov (United States)

    Panigrahy, D; Rakshit, M; Sahu, P K

    2016-03-01

    This paper describes a field programmable gate array (FPGA) implementation of a system that calculates the heart rate from Electrocardiogram (ECG) signal. After heart rate calculation, tachycardia, bradycardia or normal heart rate can easily be detected. ECG is a diagnosis tool routinely used to access the electrical activities and muscular function of the heart. Heart rate is calculated by detecting the R peaks from the ECG signal. To provide a portable and the continuous heart rate monitoring system for patients using ECG, needs a dedicated hardware. FPGA provides easy testability, allows faster implementation and verification option for implementing a new design. We have proposed a five-stage based methodology by using basic VHDL blocks like addition, multiplication and data conversion (real to the fixed point and vice-versa). Our proposed heart rate calculation (R-peak detection) method has been validated, using 48 first channel ECG records of the MIT-BIH arrhythmia database. It shows an accuracy of 99.84 %, the sensitivity of 99.94 % and the positive predictive value of 99.89 %. Our proposed method outperforms other well-known methods in case of pathological ECG signals and successfully implemented in FPGA. PMID:26643079

  6. Heart rate variability in left ventricular hypertrophy.

    OpenAIRE

    Mandawat, M. K.; Wallbridge, D R; Pringle, S.D.; Riyami, A. A.; Latif, S; MacFarlane, P. W.; Lorimer, A.R.; Cobbe, S. M.

    1995-01-01

    BACKGROUND--Electrocardiographic left ventricular hypertrophy and strain are associated with increased cardiac morbidity and mortality. Impaired cardiac autonomic function, assessed non-invasively by spontaneous heart rate variability on Holter monitoring, is associated with an increased risk of sudden death after myocardial infarction. AIM--To study the effect of left ventricular hypertrophy on heart rate variability. PATIENTS--36 controls and 154 patients with left ventricular hypertrophy (...

  7. 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.

  8. 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 electrocardiograms (ECG...

  9. 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; Zois, Nora Elisabeth; Moesgaard, Sophia Gry; Pedersen, Henrik Duelund; Häggström, Jens; Olsen, Lisbeth Høier

    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 ind...

  10. 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.

  11. What is the “normal” fetal heart rate?

    Directory of Open Access Journals (Sweden)

    Stephanie Pildner von Steinburg

    2013-06-01

    Full Text Available Aim. There is no consensus about the normal fetal heart rate. Current international guidelines recommend for the normal fetal heart rate (FHR baseline different ranges of 110 to 150 beats per minute (bpm or 110 to 160 bpm. We started with a precise definition of “normality” and performed a retrospective computerized analysis of electronically recorded FHR tracings. Methods. We analyzed all recorded cardiotocography tracings of singleton pregnancies in three German medical centers from 2000 to 2007 and identified 78,852 tracings of sufficient quality. For each tracing, the baseline FHR was extracted by eliminating accelerations/decelerations and averaging based on the “delayed moving windows” algorithm. After analyzing 40% of the dataset as “training set” from one hospital generating a hypothetical normal baseline range, evaluation of external validity on the other 60% of the data was performed using data from later years in the same hospital and externally using data from the two other hospitals. Results. Based on the training data set, the “best” FHR range was 115 or 120 to 160 bpm. Validation in all three data sets identified 120 to 160 bpm as the correct symmetric “normal range”. FHR decreases slightly during gestation. Conclusions. Normal ranges for FHR are 120 to 160 bpm. Many international guidelines define ranges of 110 to 160 bpm which seem to be safe in daily practice. However, further studies should confirm that such asymmetric alarm limits are safe, with a particular focus on the lower bound, and should give insights about how to show and further improve the usefulness of the widely used practice of CTG monitoring.

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    Vitor Oliveira Carvalho

    2008-01-01

    Full Text Available 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 exercise test. METHODS: Twenty-five heart failure patients (49±11 years, 76% male, with an average LVEF of 30±7%, and fourteen controls were included in the study. Patients with atrial fibrillation, a pacemaker or noncardiovascular functional limitations or whose drug therapy was not optimized were excluded. Optimization was considered to be 50 mg/day or more of carvedilol, with a basal heart rate between 50 to 60 bpm that was maintained for 3 months. RESULTS: Basal heart rate was lower in heart failure patients (57±3 bpm compared to controls (89±14 bpm; p<0.0001. Similarly, the peak heart rate (% maximum predicted for age was lower in HF patients (65.4±11.1% compared to controls (98.6±2.2; p<0.0001. Maximum respiratory exchange ratio did not differ between the groups (1.2±0.5 for controls and 1.15±1 for heart failure patients; p=0.42. All controls reached the maximum heart rate for their age, while no patients in the heart failure group reached the maximum. Moreover, the % increase of heart rate from rest to peak exercise between heart failure (48±9% and control (53±8% was not different (p=0.157. CONCLUSION: No patient in the heart failure group reached the maximum heart rate for their age during a treadmill cardiopulmonary exercise test, despite the fact that the percentage increase of heart rate was similar to sedentary normal subjects. A heart rate increase in optimized beta-blocked heart failure patients during cardiopulmonary exercise test over 65% of the maximum age-adjusted value should be considered an effort near the maximum. This information may be useful in rehabilitation programs and ischemic tests, although further studies are required.

  14. Heart Rate Variability - A Historical Perspective

    Directory of Open Access Journals (Sweden)

    GeorgeEBillman

    2011-11-01

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

  15. 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...

  16. Heart Rate Variability Analysis in General Medicine

    Directory of Open Access Journals (Sweden)

    Yi Gang

    2003-01-01

    Full Text Available Autonomic nervous system plays an integral role in homeostasis. Autonomic modulation can frequently be altered in patients with cardiac disorders as well as in patients with other critical illnesses or injuries. Assessment of heart rate variability is based on analysis of consecutive normal R-R intervals and may provide quantitative information on the modulation of cardiac vagal and sympathetic nerve input. The hypothesis that depressed heart rate variability may occur over a broad range of illness and injury, and may inversely correlated with disease severity and outcome has been tested in various clinical settings over the last decade. This article reviews recent literature concerning the potential clinical implications and limitations of heart rate variability assessment in general medicine.

  17. 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.

  18. Heart Rate and Increased Intravascular Volume.

    Czech Academy of Sciences Publication Activity Database

    Sou?ek, M.; Kára, T.; Jurák, Pavel; Halámek, Josef; Špinarová, L.; Meluzín, J.; Toman, J.; ?ihá?ek, I.; Šumbera, J.; Frá?a, P.

    2003-01-01

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

  19. 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.

  20. [Music and heart rate variability. Study of the effect of music on heart rate variability in healthy adolescents].

    Science.gov (United States)

    Escher, J; Evéquoz, D

    1999-05-20

    The effect of trophotropic (relaxing) music on heart rate and heart rate variability has been investigated in 23 healthy young individuals by means of 24-hour Holter-ECG. Relaxing music (Bach, Vivaldi, Mozart) resulted in significant reduction of heart rate and also significant reduction of heart rate variability. The significance of these results for the use of music in coronary heart disease is discussed. PMID:10412282

  1. Resting heart rate, heart rate variability and functional decline in old age

    DEFF Research Database (Denmark)

    Ogliari, Giulia; Mahinrad, Simin

    2015-01-01

    BACKGROUND: Heart rate and heart rate variability, markers of cardiac autonomic function, have been linked with cardiovascular disease. We investigated whether heart rate and heart rate variability are associated with functional status in older adults, independent of cardiovascular disease. METHODS: We obtained data from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER). A total of 5042 participants were included in the present study, and mean followup was 3.2 years. Heart rate and heart rate variability were derived from baseline 10-second electrocardiograms. Heart rate variability was defined as the standard deviation of normal-to-normal RR intervals (SDNN). Functional status in basic (ADL) and instrumental (IADL) activities of daily living was measured using Barthel and Lawton scales, at baseline and during follow-up. RESULTS: The mean age of the study population was 75.3 years. At baseline, higher heart rate was associated with worse ADL and IADL, and lower SDNN was related to worse IADL (all p values < 0.05). Participants in the highest tertile of heart rate (range 71-117 beats/min) had a 1.79-fold (95% confidence interval [CI] 1.45-2.22) and 1.35-fold (95% CI 1.12-1.63) higher risk of decline in ADL and IADL, respectively (p for trend < 0.001 and 0.001, respectively). Participants in the lowest tertile of SDNN (range 1.70-13.30 ms) had 1.21-fold (95% CI 1.00-1.46) and 1.25-fold (95% CI 1.05-1.48) higher risk of decline in ADL and IADL, respectively (both p for trends < 0.05). All associations were independent of sex, medications, cardiovascular risk factors and comorbidities. INTERPRETATION: Higher resting heart rate and lower heart rate variability were associated with worse functional status and with higher risk of future functional decline in older adults, independent of cardiovascular disease. This study provides insight into the role of cardiac autonomic function in the development of functional decline.

  2. A comparison between heart rate and heart rate variability as indicators of cardiac health and fitness

    OpenAIRE

    Grant, Catharina C.; Murray, Carien; Janse van Rensburg, Dina C.; Fletcher, Lizelle

    2013-01-01

    Quantification of cardiac autonomic activity and control via heart rate (HR) and heart rate variability (HRV) is known to provide prognostic information in clinical populations. Issues with regard to standardisation and interpretation of HRV data make the use of the more easily accessible HR on its own as an indicator of autonomic cardiac control very appealing. The aim of this study was to investigate the strength of associations between an important cardio vascular health metric such as VO2...

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

    DEFF Research Database (Denmark)

    Cagirci, Goksel; Cay, Serkan; Karakurt, Ozlem; Eryasar, Neslihan; Kaya, Veli; Canga, Aytun; Yesilay, Asuman Bicer; Kilic, Harun; Topaloglu, Serkan; Aras, Dursun; Demir, Ahmet; Akdemir, Ramazan

    2009-01-01

    BACKGROUND: Cigarette smoking increases the risk of cardiovascular events related with several mechanisms. The most suggested mechanism is increased activity of sympathetic nervous system. Heart rate variability (HRV) and heart rate turbulence (HRT) has been shown to be independent and powerful predictors of mortality in a specific group of cardiac patients. The goal of this study was to assess the effect of heavy cigarette smoking on cardiac autonomic function using HRV and HRT analyses. METHOD...

  4. 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.

  5. Effects of aerobic training on heart rate

    Directory of Open Access Journals (Sweden)

    Almeida Marcos B.

    2003-01-01

    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.

  6. Effects of aerobic training on heart rate

    OpenAIRE

    Almeida Marcos B.; Araújo Claudio Gil S.

    2003-01-01

    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 autorhythmici...

  7. 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.

  8. 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 to MMVD. 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.

  9. The mitochondrial uniporter controls fight or flight heart rate increases.

    Science.gov (United States)

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

    2015-01-01

    Heart rate increases are a fundamental adaptation to physiological stress, while inappropriate heart rate increases are resistant to current therapies. However, the metabolic mechanisms driving heart rate acceleration in cardiac pacemaker cells remain incompletely understood. The mitochondrial calcium uniporter (MCU) facilitates calcium entry into the mitochondrial matrix to stimulate metabolism. We developed mice with myocardial MCU inhibition by transgenic expression of a dominant-negative (DN) MCU. Here, we show that DN-MCU mice had normal resting heart rates but were incapable of physiological fight or flight heart rate acceleration. We found that MCU function was essential for rapidly increasing mitochondrial calcium in pacemaker cells and that MCU-enhanced oxidative phoshorylation was required to accelerate reloading of an intracellular calcium compartment before each heartbeat. Our findings show that MCU is necessary for complete physiological heart rate acceleration and suggest that MCU inhibition could reduce inappropriate heart rate increases without affecting resting heart rate. PMID:25603276

  10. Case Studies in Electronic Fetal Heart Rate Monitoring

    OpenAIRE

    Yee, J; Parboosingh, I.J.

    1986-01-01

    Subtle changes in the characteristics of the fetal heart rate are currently used to assess the condition of the fetus in late pregnancy and during labour. The authors present three case studies of fetal heart rate monitoring.

  11. 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.

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

    OpenAIRE

    Miriam R. Waldeck; 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...

  13. Cocaine alters heart rate dynamics in conscious ferrets.

    OpenAIRE

    Stambler, B. S.; Morgan, J P; Mietus, J.; Moody, G.B.; Goldberger, A. L.

    1991-01-01

    This study was designed to test the hypothesis that cocaine intoxication induces distinctive alterations in sinus rhythm heart rate dynamics. Time-series and spectral analysis techniques were used to examine the effects of lethal doses of cocaine on heart rate variability in conscious, restrained ferrets. In all animals (n = 5), cocaine administration resulted in a marked decrease in sinus rhythm heart rate variability prior to sudden death. Heart rate variability (coefficient of variation of...

  14. Intermittency in Human Heart Rate Variability

    International Nuclear Information System (INIS)

    Intermittency in time series of the time intervals between heart beats (RR intervals) extracted from 24 hour (portable) ECG is found for some cases of humans with arrhythmia. Laminar phases are found by sweeping a short (5 intervals) time window through the time series and calculating the standard deviation of the series in each window. 8 of the 18 arrhythmia cases studied had a bimodal distribution of the standard deviation values indicating some kind of intermittency. The distribution of lengths of the laminar phases identifies the intermittency obtained in human heart rate variability as Type 1 in the Pomeau and Manneville classification. Although the arrhythmia cases studied were medically very different - in those instances that intermittency did occur the probability distributions of laminar phase lengths were strikingly similar. (author)

  15. 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.

  16. 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.

  17. Heart rate response to hypoxic exercise

    DEFF Research Database (Denmark)

    Lundby, C; Møller, P; Kanstrup, I L; Olsen, Niels Vidiendal

    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 medi...

  18. 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, 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)

  19. Effect of Yoga Therapy on Heart Rate, Blood Pressure and Cardiac Autonomic Function in Heart Failure

    OpenAIRE

    Krishna, Bandi Hari; Pal, Pravati; G.K., Pal; J., Balachander; E., Jayasettiaseelon; Y, Sreekanth; M.G., Sridhar; G.S., Gaur

    2014-01-01

    Background and Objective: It is well known that a hall mark of heart failure is adverse changes in autonomic function. Elevated blood pressure is a powerful predictor of congestive heart failure and other Cardiovascular Disease (CVD) outcomes. In this study, we planned to examine the effects of a 12 week yoga therapy on blood pressure, heart rate, heart rate variability, and rate pressure product (RPP).

  20. 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

  1. General anesthesia suppresses normal heart rate variability in humans

    Science.gov (United States)

    Matchett, Gerald; Wood, Philip

    2014-06-01

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

  2. Procedural Pain Heart Rate Responses in Massaged Preterm Infants

    OpenAIRE

    Diego, Miguel A.; Field, Tiffany; Hernandez-Reif, Maria

    2009-01-01

    Heart rate (HR) responses to the removal of a monitoring lead were assessed in 56 preterm infants who received moderate pressure, light pressure or no massage therapy. The infants who received moderate pressure massage therapy exhibited lower increases in HR suggesting an attenuated pain response. The heart rate of infants who received moderate pressure massage also returned to baseline faster than the heart rate of the other two groups, suggesting a faster recovery rate.

  3. Modeling baroreflex regulation of heart rate during orthostatic stress

    DEFF Research Database (Denmark)

    Olufsen, Mette; Tran, Hien T.; Ottesen, Johnny T.; Lipsitz, Lewis A.; Novak, Vera

    2006-01-01

    During orthostatic stress, arterial and cardiopulmonary baroreflexes play a key role in maintaining arterial pressure by regulating heart rate. This study, presents a mathematical model that can predict the dynamics of heart rate regulation in response to postural change from sitting to standing. The model uses blood pressure measured in the finger as an input to model heart rate dynamics in response to changes in baroreceptor nerve firing rate, sympathetic and parasympathetic responses, vestibu...

  4. 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.

  5. 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.

  6. Ordinal pattern statistics for the assessment of heart rate variability

    Science.gov (United States)

    Graff, G.; Graff, B.; Kaczkowska, A.; Makowiec, D.; Amigó, J. M.; Piskorski, J.; Narkiewicz, K.; Guzik, P.

    2013-06-01

    The recognition of all main features of a healthy heart rhythm (the so-called sinus rhythm) is still one of the biggest challenges in contemporary cardiology. Recently the interesting physiological phenomenon of heart rate asymmetry has been observed. This phenomenon is related to unbalanced contributions of heart rate decelerations and accelerations to heart rate variability. In this paper we apply methods based on the concept of ordinal pattern to the analysis of electrocardiograms (inter-peak intervals) of healthy subjects in the supine position. This way we observe new regularities of the heart rhythm related to the distribution of ordinal patterns of lengths 3 and 4.

  7. 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.

  8. 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 ...

  9. AUTONOMIC CONTROL OF HEART RATE AFTER EXERCISE IN TRAINED WRESTLERS

    OpenAIRE

    Carlos F Henríquez; Eduardo Báez; Astrid Von Oetinger; Rodrigo Cañas; Rodrigo Ramírez

    2013-01-01

    The objective of this study was to establish differences in vagal reactivation, through heart rate recovery and heart rate variability post exercise, in Brazilian jiu-jitsu wrestlers (BJJW). A total of 18 male athletes were evaluated, ten highly trained (HT) and eight moderately trained (MT), who performed a maximum incremental test. At the end of the exercise, the R-R intervals were recorded during the first minute of recovery. We calculated heart rate recovery (HRR60s), and performed linear...

  10. Dynamic Modelling of Heart Rate Response Under Different Exercise Intensity

    OpenAIRE

    Su, Steven W; CHEN, WEIDONG; Liu, Dongdong; Fang, Yi; Kuang, Weijun; Yu, Xiaoxiang; Guo, Tian; Celler, Branko G; Hung T. Nguyen

    2010-01-01

    Heart rate is one of the major indications of human cardiovascular response to exercises. This study investigates human heart rate response dynamics to moderate exercise. A healthy male subject has been asked to walk on a motorised treadmill under a predefined exercise protocol. ECG, body movements, and oxygen saturation (SpO2) have been reliably monitored and recorded by using non-invasive portable sensors. To reduce heart rate variation caused by the influence of various internal or externa...

  11. Heart Rate Turbulence as Risk-Predictor after Myocardial Infarction

    OpenAIRE

    ChristineStefanieZuern; PetraBarthel

    2011-01-01

    Heart Rate Turbulence (HRT) is the baroreflex-mediated short-term oscillation of cardiac cycle lengths after spontaneous ventricular premature complexes (VPC). HRT is composed of a brief heart rate acceleration followed by a gradual heart rate deceleration. In high risk patients after myocardial infarction (MI) HRT is blunted or diminished. Since its first description in 1999 HRT emerged as one of the most potent risk factors after MI. Predictive power of HRT has been studied in more than 10,...

  12. Information variables in voluntary control and classical conditioning of heart rate: field dependence and heart-rate perception.

    Science.gov (United States)

    Dale, A; Anderson, D

    1978-08-01

    Two experiments focused on two information variables relevant to changes in heart rate, field dependence and the ability to perceive one's own heart rate. In Exp. I, 14 field-independent and 17 field-dependent subjects completed a heart-rate perception and a voluntary heart-rate control task. The anticipated superiority in heart-rate control by field-independent subjects was detected although no evidence was found for a relationship between the amount of biofeedback available in the situation and voluntary control of the cardiovascular system. Exp. II involved 9 field-independent and 8 field-dependent subjects in a classical conditioning paradigm involving shock sensitivity. In contrast with Exp. I, in this phase of the study heart-rate increases were correlated with the ability of the subject to discriminate heart beats, especially for the field-independent group. It was concluded that field dependence and heart-rate perception are related to classically conditioned heart-rate increase for some subjects and further that field dependence may be a potent variable operating in those situations involving the voluntary control of heart rate without exteroceptive feedback. PMID:704264

  13. 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.

  14. 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

  15. Study Heart Rate by Tools from Complex Networks

    International Nuclear Information System (INIS)

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

  16. Assessing Heart Rate in Physical Education. Assessment Series: K-12 Physical Education.

    Science.gov (United States)

    Buck, Marilyn M.

    This guide discusses the assessment of heart rate and, in particular, the assessment of heart rate using a heart monitor. Part 1, "Foundation for the Use of Heart Rate," reviews literature about heart rate assessment and heart rate monitors, offering an overview of national guidelines for physical activity. It focuses on the importance of physical…

  17. Fetal heart rate and fetal heart rate variability in Lipizzaner broodmares.

    Science.gov (United States)

    Baska-Vincze, Boglárka; Baska, Ferenc; Szenci, Ottó

    2015-03-01

    Monitoring fetal heart rate (FHR) and fetal heart rate variability (FHRV) helps to understand and evaluate normal and pathological conditions in the foal. The aim of this study was to establish normal heart rate reference values for the ongoing equine pregnancy and to perform a heart rate variability (HRV) time-domain analysis in Lipizzaner mares. Seventeen middle- and late-term (days 121-333) pregnant Lipizzaner mares were examined using fetomaternal electrocardiography (ECG). The mean FHR (P = 0.004) and the standard deviation of FHR (P = 0.012) significantly decreased during the pregnancy. FHR ± SD values decreased from 115 ± 35 to 79 ± 9 bpm between months 5 and 11. Our data showed that HRV in the foal decreased as the pregnancy progressed, which is in contrast with the findings of earlier equine studies. The standard deviation of normal-normal intervals (SDNN) was higher (70 ± 25 to 166 ± 108 msec) than described previously. The root mean square of successive differences (RMSSD) decreased from 105 ± 69 to 77 ± 37 msec between the 5th and 11th month of gestation. Using telemetric ECG equipment, we could detect equine fetal heartbeat on day 121 for the first time. In addition, the large differences observed in the HR values of four mare-fetus pairs in four consecutive months support the assumption that there might be 'high-HR' and 'low-HR' fetuses in horses. It can be concluded that the analysis of FHR and FHRV is a promising tool for the assessment of fetal well-being but the applicability of these parameters in the clinical setting and in studs requires further investigation. PMID:25655416

  18. Bluetooth(Registered Trademark) Heart Rate Monitors for Spaceflight

    Science.gov (United States)

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

    2016-01-01

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

  19. 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...

  20. Heart Rate and Cardiovascular Disease: An Alternative to Beta Blockers

    OpenAIRE

    Michael Liang; Aniket Puri; Gerard Devlin

    2009-01-01

    Ivabradine, an If inhibitor, acts primarily on the sinoatrial node and is used to reduce the heart rate with minimal effect on myocardial contractility, blood pressure, and intracardiac conduction. Heart rate reduction is an important aspect of care in patients with chronic stable angina and heart failure. Many patients with coronary artery disease have coexisting asthma or chronic obstructive airway disease, and most of them are unable to tolerate beta blockers. Ivabradine may thus be a usef...

  1. [Study on the activity--heart rate prediction system for motion sensed rate responsive pacemakers].

    Science.gov (United States)

    Guo, Ping; Sun, Weixin; Jin, Jie; Zhao, Qingping; Chen, Xiang; Kong, Shu; Huang, Yizhuo

    2011-09-01

    Focusing on the heart rate control mode of acceleration sensor based rate responsive pacemakers, this paper implemented the design of activity--heart rate prediction system. Bluetooth module was used as communication means in activity--heart rate prediction system, and the slave computer was used to complete the acceleration signal acquisition and processing, map from acceleration signal to the pacing rate signal, and achieve real-time transmission of acceleration signal and heart rate signal. The master computer fulfilled real-time display and recording of acceleration signal and heart rate signal, moreover, it achieved control function to the slave computer algorithm through classification of 6 parameters. The results of verification experiment showed that there was a significant relation between mapping heart rate and actual heart rate using linear mapping algorithm (R2 = 0.787, P < 0.001). PMID:22242376

  2. Fetal Heart Rate Patterns in Monochorionic Twins Following Acute Twin-Twin Transfusion

    OpenAIRE

    Tomoaki Murata; Miwa Igarashi; Shuichi Ono; Nao Iwasaki; Shunji Suzuki

    2009-01-01

    Background. We present here 2 cases of acute twin-twin transfusion occurred during vaginal labor in monochorionic-diamniotic twin pregnancies. Case. Fetal heart rate tracings showed tachycardia in the donor twin in the first case, while they showed reassuring patterns in both twins in the second case. Conclusion. These differences in changes of fetal heart rate in the donor twins following acute twin-twin transfusion may be resulted from the differences in amount of transfusion and elapsed time.

  3. Effect of Age and Other Factors on Maximal Heart Rate.

    Science.gov (United States)

    Londeree, Ben R.; Moeschberger, Melvin L.

    1982-01-01

    To reduce confusion regarding reported effects of age on maximal exercise heart rate, a comprehensive review of the relevant English literature was conducted. Data on maximal heart rate after exercising with a bicycle, a treadmill, and after swimming were analyzed with regard to physical fitness and to age, sex, and racial differences. (Authors/PP)

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

    International Nuclear Information System (INIS)

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

  5. Relation between heart rate, heart rhythm, and reverse left ventricular remodelling in response to carvedilol in patients with chronic heart failure: a single centre, observational study

    OpenAIRE

    Arnold, R H; Kotlyar, E; Hayward, C.; Keogh, A M; Macdonald, P S

    2003-01-01

    Objective: To determine whether the process of reverse left ventricular remodelling in response to carvedilol is dependent on baseline heart rate (BHR), heart rhythm, or heart rate reduction (HRR) in response to carvedilol.

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

    DEFF Research Database (Denmark)

    Carlson, Nicholas; Dixen, Ulrik; Marott, Jacob L; Jensen, Magnus T; Jensen, Gorm B

    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 ...

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

    Science.gov (United States)

    Ackerly, Spafford C.

    2001-01-01

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

  8. High readmission rate after heart valve surgery

    DEFF Research Database (Denmark)

    Sibilitz, K L; Berg, S K; Thygesen, L C; Hansen, T B; Køber, L; Hassager, C; Zwisler, A-D

    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 answe...

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

    Directory of Open Access Journals (Sweden)

    Häggström J

    2003-09-01

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

  10. Abnormal intermittency of heart rate in patients with neurocardiogenic syncope

    Science.gov (United States)

    Yum, Myung-Kul; Kim, Kyung-Sik; Kim, June-Soo

    2002-03-01

    Introduction: We aim to test our hypothesis that, during daily activity, though not as prominent as during HUT test, the patients may show different degree of intermittency in heart rates compared to healthy persons. METHOD AND RESULTS: Thirty patients with neurocardiogenic syncope who showed a positive HUT test and thirty healthy controls without history of syncope were included. Their twenty-four hour ambulatory electrocardiograms were digitized and RR interval (RRI) data of six-hour interval were analyzed. To quantify the intermittency (C1) behavior, The intermittency analysis was performed using Mexican hat wavelet. For the syncope group, the values of C1 were significantly higher at 6AM-6PM and lower at 6AM-midnight, respectively. However, the values were not different at midnight-6AM. The significant night-day circadian change shown in the control group was lost in C1. CONCLUSION: When compared to healthy control, the patients with neurocardiogenic syncope shows increased intermittency of heart rates in daytime during daily activity, and abnormal circadian rhythms of the index. These new findings may be useful for investigating the pathophysiology of neurocardiogenic syncope and early identification of the patients.

  11. 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 function did not change significantly with HR. Rate control drugs may be used in preference to improve symptoms in moderate and severe MS. (author)

  12. Design and Development of a Heart Rate Measuring Device using Fingertip

    OpenAIRE

    Hashem, M. M. A; Shams, Rushdi; Kader, Md Abdul; Sayed, Md. Abu

    2013-01-01

    In this paper, we presented the design and development of a new integrated device for measuring heart rate using fingertip to improve estimating the heart rate. As heart related diseases are increasing day by day, the need for an accurate and affordable heart rate measuring device or heart monitor is essential to ensure quality of health. However, most heart rate measuring tools and environments are expensive and do not follow ergonomics. Our proposed Heart Rate Measuring (H...

  13. Heart rate-lowering therapy in the treatment of chronic heart failure

    Directory of Open Access Journals (Sweden)

    S.V. Shalaev

    2015-02-01

    Full Text Available Aspects of heart rate-lowering therapy in patients with chronic heart failure using If-channel blocker ivabradine are discussed. The evidence-based data on ivabradine use reveal its advantages, disadvantages and place in the treatment of cardiac patients.

  14. Wine drinking is associated with increased heart rate variability in women with coronary heart disease

    OpenAIRE

    Janszky, I; Ericson, M; Blom, M; Georgiades, A; Magnusson, J-O; Alinagizadeh, H; Ahnve, S

    2005-01-01

    Objective: To test the hypothesis that alcohol consumption is positively related to heart rate variability (HRV) in women with coronary heart disease (CHD) and therefore that cardiac autonomic activity is potentially implicated in the mediation of the favourable effects of moderate drinking.

  15. 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

  16. Effect of immersion, submersion, and scuba diving on heart rate variability

    OpenAIRE

    Schipke, J; Pelzer, M

    2001-01-01

    Background—Heart rate variability (HRV) describes the cyclic variations in heart rate and offers a non-invasive tool for investigating the modulatory effects of neural mechanisms elicited by the autonomic nervous system on intrinsic heart rate.

  17. The fall in the rate of death from heart diseases

    International Nuclear Information System (INIS)

    A self limiting interaction between heart disease producing factors and genetic factors is postulated. Such an interaction could be responsable for the fall in rate of death from ischemic disease observed in the United States. (Author)

  18. Heart Rate Response and Lactic Acid Concentration in Squash Players.

    Science.gov (United States)

    Beaudin, Paula; And Others

    1978-01-01

    It was concluded that playing squash is an activity that results in heart rate responses of sufficient intensity to elicit aerobic training effects without producing high lactic acid concentration in the blood. (MM)

  19. Recurrence Plots of Heart Rate Signals during Meditation

    Directory of Open Access Journals (Sweden)

    Ateke Goshvarpour

    2012-03-01

    Full Text Available The current study analyses the dynamics of the heart rate signals during specific psychological states in order to obtain a detailed understanding of the heart rate patterns during meditation. In the proposed approach, heart rate time series available in Physionet database are used. The dynamics of the signals are then analyzed before and during meditation by examining the attractors in the phase space and recurrence quantification analysis. In general, the results reveal that the heart rate signals transit from a chaotic, highly-complex behavior before meditation to a low dimensional chaotic (and quasi-periodic motion during meditation. This can be due to decreased nonlinear interaction of variables in meditation states and may be related to increased parasympathetic activity and increase of relaxation state. The results suggest that nonlinear chaotic indices may serve as a quantitative measure for psychophysiological states.

  20. 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)

  1. Dynamic modelling of heart rate response under different exercise intensity.

    Science.gov (United States)

    Su, Steven W; Chen, Weidong; Liu, Dongdong; Fang, Yi; Kuang, Weijun; Yu, Xiaoxiang; Guo, Tian; Celler, Branko G; Nguyen, Hung T

    2010-01-01

    Heart rate is one of the major indications of human cardiovascular response to exercises. This study investigates human heart rate response dynamics to moderate exercise. A healthy male subject has been asked to walk on a motorised treadmill under a predefined exercise protocol. ECG, body movements, and oxygen saturation (SpO2) have been reliably monitored and recorded by using non-invasive portable sensors. To reduce heart rate variation caused by the influence of various internal or external factors, the designed step response protocol has been repeated three times. Experimental results show that both steady state gain and time constant of heart rate response are not invariant when walking speed is faster than 3 miles/hour, and time constant of offset exercise is noticeably longer than that of onset exercise. PMID:20694159

  2. 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.

  3. Heart Rate Responses to Parental Behavior in Depressed Adolescents

    OpenAIRE

    ALLEN, NICHOLAS B.; Kuppens, Peter; Sheeber, Lisa

    2012-01-01

    In order to more fully understand the abnormalities in emotional responding associated with adolescent depression we examined clinically depressed and non-depressed adolescents’ physiological responses to their parents’ negative emotional behavior, as indexed by their heart rate responses to parental angry and dysphoric behavior during laboratory-based interactions. Maternal angry and dysphoric behavior predicted heart rate deceleration amongst non-depressed adolescents, a response that was n...

  4. HEART RATE AND ACTIVITY PROFILE FOR YOUNG FEMALE SOCCER

    OpenAIRE

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

    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...

  5. A comparison of heart rate responses in racquet games.

    OpenAIRE

    Docherty, D.

    1982-01-01

    The present study investigated the heart rate response to playing tennis with special reference to the skill levels and ages of the participants. Data obtained in a similar manner during earlier studies of badminton and squash players were compared with that obtained during tennis. The number of rallies, mean rally time and actual playing time in 30 minutes of play was also compared for the different skill levels and sports. Results showed that playing tennis raised the players' heart rates t...

  6. Assessment of anxiety using heart rate nonlinear dynamics

    Science.gov (United States)

    Thayer, Julian F.; Friedman, Bruce H.

    1993-11-01

    Various anxiety states have been linked with disorders of the autonomic nervous system. These autonomic disorders may be revealed by analysis of physiological time series such as the heart rate interbeat interval series. The present paper reports a general model of biological system functioning and related assessment indices based on recent nonlinear dynamical systems approaches. In particular, two experimental studies are reported which suggest the utility of heart rate nonlinear dynamics in the assessment of anxiety.

  7. QT measurement and heart rate correction during hypoglycemia

    DEFF Research Database (Denmark)

    Christensen, Toke Folke; Randløv, Jette; Christensen, Leif Engmann; Eldrup, Ebbe; Hejlesen, Ole K.; Struijk, Johannes

    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 u...

  8. Effect of oxygen treatment on heart rate after abdominal surgery

    DEFF Research Database (Denmark)

    Rosenberg-Adamsen, S; Lie, C; Bernhard, A; Kehlet, H; Rosenberg, J

    1999-01-01

    BACKGROUND: Cardiac complications are common during the postoperative period and may be associated with hypoxemia and tachycardia. Preliminary studies in high-risk patients after operation have shown a possible beneficial effect of oxygen therapy on arterial oxygen saturation and heart rate. METHODS: The authors studied the effect of oxygen therapy on arterial oxygen saturation and heart rate in 100 consecutive unselected patients randomly and double blindly allocated to receive air or oxygen th...

  9. 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 ...

  10. 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...

  11. 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.

  12. 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

  13. 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.

  14. Heart rate variability and heat sensation during CT coronary angiography: Low-osmolar versus iso-osmolar contrast media

    International Nuclear Information System (INIS)

    Background: During computed tomography coronary angiography (CTCA) unexpected changes in heart rate while scanning may affect image quality. Purpose: To evaluate whether an iso-osmolar contrast medium (IOCM, iodixanol) and a low-osmolar contrast medium (LOCM, iomeprol) affect heart rate and experienced heat sensation differently. Material and Methods: One hundred patients scheduled for CTCA were randomized to receive either iodixanol 320 mgI/ml or iomeprol 400 mgI/ml. Depending on their heart rate, the patients were assigned to one of five scanning protocols, each optimized for different heart rate ranges. During scanning the time between each heart beat (hb) was recorded, and the corresponding heart rate was calculated. For each contrast medium (CM) the average heart rate, the variation in heart rate from individual mean heart rate, and the mean deviation from the predefined scanning protocol were calculated. Experience of heat was obtained immediately after scanning by using a visual analog scale (VAS). Examination quality was rated by two radiologists on a three-point scale. Results: The mean variation in heart rate after IOCM was 1.4 hb/min and after LOCM it was 4.4 hb/min (NS). The mean deviations in heart rate from that in the predefined scanning protocol were 2.0 hb/min and 4.7 hb/min, respectively (NS). A greater number of arrhythmic hb were observed after LOCM compared with IOCM (P<0.001). There was no statistically significant difference in image quality. The LOCM group reported a stronger heat sensation after CM injection than the IOCM group (VAS =36 mm and 18 mm, P<0.05). Conclusion: At clinically used concentrations the IOCM, iodixanol 320 mgI/ml, does not increase the heart rate during CTCA and causes less heart arrhythmia and less heat sensation than the LOCM, iomeprol 400 mgI/ml

  15. Heart rate variability and heat sensation during CT coronary angiography: Low-osmolar versus iso-osmolar contrast media

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Anders; Ripsweden, Jonaz; Aspelin, Peter; Cederlund, Kerstin; Brismar, B. Torkel (Dept. of Clinical Science, Intervention and Technology, Karolinska Inst., Div. of Medical Imaging and Technology and Dept. of Radiology, Karolinska Univ. Hospital, Huddinge, Stockholm (Sweden)), e-mail: anders.svensson@karolinska.se; Rueck, Andreas (Div. of Cardiology, Dept. of Internal Medicine, Karolinska Inst., Karolinska Univ. Hospital, Stockholm (Sweden))

    2010-09-15

    Background: During computed tomography coronary angiography (CTCA) unexpected changes in heart rate while scanning may affect image quality. Purpose: To evaluate whether an iso-osmolar contrast medium (IOCM, iodixanol) and a low-osmolar contrast medium (LOCM, iomeprol) affect heart rate and experienced heat sensation differently. Material and Methods: One hundred patients scheduled for CTCA were randomized to receive either iodixanol 320 mgI/ml or iomeprol 400 mgI/ml. Depending on their heart rate, the patients were assigned to one of five scanning protocols, each optimized for different heart rate ranges. During scanning the time between each heart beat (hb) was recorded, and the corresponding heart rate was calculated. For each contrast medium (CM) the average heart rate, the variation in heart rate from individual mean heart rate, and the mean deviation from the predefined scanning protocol were calculated. Experience of heat was obtained immediately after scanning by using a visual analog scale (VAS). Examination quality was rated by two radiologists on a three-point scale. Results: The mean variation in heart rate after IOCM was 1.4 hb/min and after LOCM it was 4.4 hb/min (NS). The mean deviations in heart rate from that in the predefined scanning protocol were 2.0 hb/min and 4.7 hb/min, respectively (NS). A greater number of arrhythmic hb were observed after LOCM compared with IOCM (P<0.001). There was no statistically significant difference in image quality. The LOCM group reported a stronger heat sensation after CM injection than the IOCM group (VAS =36 mm and 18 mm, P<0.05). Conclusion: At clinically used concentrations the IOCM, iodixanol 320 mgI/ml, does not increase the heart rate during CTCA and causes less heart arrhythmia and less heat sensation than the LOCM, iomeprol 400 mgI/ml

  16. 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.

  17. 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.

  18. 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.

  19. 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).

  20. Cuff inflation during ambulatory blood pressure monitoring and heart rate

    Directory of Open Access Journals (Sweden)

    Mia Skov-Madsen

    2008-11-01

    Full Text Available Mia Skov-Madsen, My Svensson, Jeppe Hagstrup ChristensenDepartment of Nephrology, Aarhus University Hospital, Aalborg, DenmarkIntroduction: Twenty four-hour ambulatory blood pressure monitoring is a clinically validated procedure in evaluation of blood pressure (BP. We hypothesised that the discomfort during cuff inflation would increase the heart rate (HR measured with 24-h ambulatory BP monitoring compared to a following HR measurement with a 24-h Holter monitor.Methods: The study population (n = 56 were recruited from the outpatient’s clinic at the Department of Nephrology, Aalborg Hospital, Aarhus University Hospital at Aalborg, Denmark. All the patients had chronic kidney disease (CKD. We compared HR measured with a 24-h Holter monitor with a following HR measured by a 24-h ambulatory BP monitoring.Results: We found a highly significant correlation between the HR measured with the Holter monitor and HR measured with 24-h ambulatory blood pressure monitoring (r = 0.77, p < 0.001. Using the Bland-Altman plot, the mean difference in HR was only 0.5 beat/min during 24 hours with acceptable limits of agreement for both high and low HR levels. Dividing the patients into groups according to betablocker treatment, body mass index, age, sex, angiotensin-converting enzyme inhibitor treatment, statins treatment, diuretic treatment, or calcium channel blocker treatment revealed similar results as described above.Conclusion: The results indicate that the discomfort induced by cuff inflation during 24-h ambulatory BP monitoring does not increase HR. Thus, 24-h ambulatory BP monitoring may be a reliable measurement of the BP among people with CKD.Keywords: ambulatory blood pressure monitoring, Holter monitoring, heart rate, chronic kidney disease, hypertension

  1. When heart goes “BOOM” to fast. Heart rate greater than 80 as mortality predictor in acute myocardial infarction

    OpenAIRE

    Davidovic, Goran; Iric-Cupic, Violeta; Milanov, Srdjan; Dimitijevic, Aleksandra; Petrovic-Janicijevic, Mirjana

    2013-01-01

    Many prospective studies established association between high heart rate and increased cardiovascular morbidity and mortality, independently of other risk factors. Heart rate over 80 beats per minute more often leads to atherosclerotic plaque disruption, the main step in developing acute coronary syndrome. Purpose was to investigate the incidence of higher heart rate levels in patients with anterior wall acute myocardial infarction with ST-segment elevation and the influence of heart rate on ...

  2. Effect of furosemide and torasemide on heart rate variability and ventricular rhythm disorders in patients with chronic heart failure complicating ischemic heart disease: comparative nonrandomized study

    Directory of Open Access Journals (Sweden)

    H.H. Shugushev

    2010-01-01

    Full Text Available Aim. To study effect of diuretic therapy with furosemide and torasemide on heart rate variability (HRV and frequency of ventriclar rhythm disorders in patients with chronic heart failure (CHF complicating ischemic heart disease (IHD.Material and methods. Patients (n=107 with CHF III-IV functional class (NYHA complicating IHD were examined. The first group of patients received furosemide, 20-60 mg QD (n=52, the second group received torasemide, 5-20 mg QD (n=55. Analysis of heart rhythm disorders and the basic HRV indicators was performed by ECG 10-minute recordings initially and after 10 days of therapy.Results. Decrease in time and spectral HRV parameters and increase in daily number of ventricular extrasystoles was found in furosemide treated patients. Improvement of HRV parameters and reduction of daily number of ventricular rhythm disorders was found torasemide treated patients.Conclusion. Torasemide therapy improves an autonomic regulation of heart rhythm and leads to the reduction of ventricular heart rhythm disorders in patients with CHF complicating IHD.

  3. Heart rate recovery in exercise test in diabetic patients with and without microalbuminuria

    Science.gov (United States)

    Pourmoghaddas, Ali; Moghaddasian, Adrineh; Garakyaraghi, Mohammad; Nezarat, Negin; Mehrabi, Ali

    2013-01-01

    BACKGROUND Diabetes mellitus (DM) has a lot of complications such as macrovessel and microvessel disease. Another complication of DM is cardiac autonomic neuropathy (CAN), which have effect on automatic nervous system of heart. Failure in heart rate slowing after exercise is a presentation of this abnormality. METHODS We selected diabetic patients and divided them to case and control group based on microalbuminuria. Case group comprised of diabetic patients with microalbuminuria and control group included those without microalbuminuria. Patients in both groups exercised on treadmill using Bruce protocol and heart rate was measured in first and second minutes in the recovery period. RESULTS We selected 35 patients with microalbuminuria (case group) and 35 without microalbuminuria (control group) among diabetic patients. No statistically significant difference was seen in sex and age between case and control groups. Heart rate recovery in the first minute of recovery in the case and control groups did not show significant difference; but in the second minute of recovery, it was significantly higher in control group (97 ± 19.4 vs. 101.9 ± 12.4 beat per minute, P = 0.04). CONCLUSION In this study we evaluated the heart rate recovery or deceleration in diabetic patients with albuminuria and without microalbuminuria in recovery phase after exercise test. We found out that heart rate recovery at the second minute in the case and control groups has statistically significant difference but at the first minute, it did not. PMID:23766772

  4. Heart rate variability in infants with West syndrome

    DEFF Research Database (Denmark)

    Møller, Michelle Mai; Høgenhaven, Hans; Uldall, Peter; Ballegaard, Martin

    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...

  5. Erythrocyte sedimentation rate as a marker for coronary heart disease

    OpenAIRE

    Yayan J

    2012-01-01

    Josef YayanDepartment of Internal Medicine, Vinzentius Hospital, Landau, GermanyBackground: Patients with angina pectoris or myocardial infarction frequently present without evidence of cardiac-specific heart enzymes by laboratory analysis or specific pathologic electrocardiogram findings. The current study analyzed the efficacy of the erythrocyte sedimentation rate as an additional potential indicator for coronary heart disease, the aim being to enable quicker identification of patients with...

  6. Self?Rated Health Predicts Healthcare Utilization in Heart Failure

    Science.gov (United States)

    Chamberlain, Alanna M.; Manemann, Sheila M.; Dunlay, Shannon M.; Spertus, John A.; Moser, Debra K.; Berardi, Cecilia; Kane, Robert L.; Weston, Susan A.; Redfield, Margaret M.; Roger, Véronique L.

    2014-01-01

    Background Heart failure (HF) patients experience impaired functional status, diminished quality of life, high utilization of healthcare resources, and poor survival. Yet, the identification of patient?centered factors that influence prognosis is lacking. Methods and Results We determined the association of 2 measures of self?rated health with healthcare utilization and skilled nursing facility (SNF) admission in a community cohort of 417 HF patients prospectively enrolled between October 2007 and December 2010 from Olmsted County, MN. Patients completed a 12?item Short Form Health Survey (SF?12). Low self?reported physical functioning was defined as a score ?25 on the SF?12 physical component. The first question of the SF?12 was used as a measure of self?rated general health. After 2 years, 1033 hospitalizations, 1407 emergency department (ED) visits, and 19,780 outpatient office visits were observed; 87 patients were admitted to a SNF. After adjustment for confounding factors, an increased risk of hospitalizations (1.52 [1.17 to 1.99]) and ED visits (1.48 [1.04 to 2.11]) was observed for those with low versus moderate?high self?reported physical functioning. Patients with poor and fair self?rated general health also experienced an increased risk of hospitalizations (poor: 1.73 [1.29 to 2.32]; fair: 1.46 [1.14 to 1.87]) and ED visits (poor: 1.73 [1.16 to 2.56]; fair: 1.48 [1.13 to 1.93]) compared with good?excellent self?rated general health. No association between self?reported physical functioning or self?rated general health with outpatient visits and SNF admission was observed. Conclusion In community HF patients, self?reported measures of physical functioning predict hospitalizations and ED visits, indicating that these patient?reported measures may be useful in risk stratification and management in HF. PMID:24870937

  7. The Effect of Valsartan on Heart Rate Variability and Heart Rate Recovery in Patients with Mild to Moderate Mitral Stenosis

    Directory of Open Access Journals (Sweden)

    Ali Metin Esen

    2010-04-01

    Full Text Available Summary: Atrial fibrillation (AF is known to be one of the most important complications of mitral stenosis (MS. It has been reported that autonomic nervous system (ANS had an effect on AF development, heart rate variability (HRV and heart rate recovery (HRR were under the control of ANS, and their disorders were present in MS. We studied the effect of Valsartan on HRV and HRT, and thus its effect on ANS. Methods: Eleven patients (39±8 years, 10 females with mild to moderate MS were included in the study. Sixteen volunteers (38±8 years, 14 females matched for age and sex were selected for control group. All subjects underwent transthoracic echocardiography (TTE, symptom-limited treadmill test and 24 hour Holter monitorization.The patients were administered 160 mg of Valsartan daily for 14 weeks. TTE, treadmill test and Holter monitorization were repeated at the end of treatment period. In Holter monitorization, the time and frequency domain analysis of HRV and in exercise test, HRR at first and third minutes (HRR1 and HRR3 were examined. Results: Before Valsartan treatment, no significant difference was found in HRR and HRV parameters between the two groups. Systolic and diastolic blood pressure, and also HRR1values were significantly decreased after treatment of Valsartan (117±6 vs. 107±4 mmHg p<0.002, 76±6 vs. 69±9 mmHg p<0.044, 44±14 vs. 33±12 p< 0.014, respectively, while the exercise time was significantly increased (786±114 vs. 846±95 sn p< 0.044. In Holter analysis neither time nor frequency domain of HRV parameters showed a meaningful change. Conclusion: In moderate MS, treatment with Valsartan improved the effort capacity, while autonomic function parameters have been defined on the base of HRV and HRR were not significantly different.

  8. Autonomic control of heart rate after exercise in trained wrestlers.

    Science.gov (United States)

    Henríquez, Olguín C; Báez, San Martín E; Von Oetinger, A; Cañas, Jamett R; Ramírez, Campillo R

    2013-06-01

    The objective of this study was to establish differences in vagal reactivation, through heart rate recovery and heart rate variability post exercise, in Brazilian jiu-jitsu wrestlers (BJJW). A total of 18 male athletes were evaluated, ten highly trained (HT) and eight moderately trained (MT), who performed a maximum incremental test. At the end of the exercise, the R-R intervals were recorded during the first minute of recovery. We calculated heart rate recovery (HRR60s), and performed linear and non-linear (standard deviation of instantaneous beat-to-beat R-R interval variability - SD1) analysis of heart rate variability (HRV), using the tachogram of the first minute of recovery divided into four segments of 15 s each (0-15 s, 15-30 s, 30-45 s, 45-60 s). Between HT and MT individuals, there were statistically significant differences in HRR60s (p <0.05) and in the non linear analysis of HRV from SD130-45s (p <0.05) and SD145-60s (p <0.05). The results of this research suggest that heart rate kinetics during the first minute after exercise are related to training level and can be used as an index for autonomic cardiovascular control in BJJW. PMID:24744476

  9. AUTONOMIC CONTROL OF HEART RATE AFTER EXERCISE IN TRAINED WRESTLERS

    Directory of Open Access Journals (Sweden)

    Carlos F Henríquez

    2013-04-01

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

  10. Heart rate measurement based on face video sequence

    Science.gov (United States)

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

    2015-03-01

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

  11. 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…

  12. Pulse rate variability compared with Heart Rate Variability in children with and without sleep disordered breathing.

    Science.gov (United States)

    Dehkordi, Parastoo; Garde, Ainara; Karlen, Walter; Wensley, David; Ansermino, J Mark; Dumont, Guy A

    2013-01-01

    Heart Rate Variability (HRV), the variation of time intervals between heartbeats, is one of the most promising and widely used quantitative markers of autonomic activity. Traditionally, HRV is measured as the series of instantaneous cycle intervals obtained from the electrocardiogram (ECG). In this study, we investigated the estimation of variation in heart rate from a photoplethysmography (PPG) signal, called pulse rate variability (PRV), and assessed its accuracy as an estimate of HRV in children with and without sleep disordered breathing (SDB). We recorded raw PPGs from 72 children using the Phone Oximeter, an oximeter connected to a mobile phone. Full polysomnography including ECG was simultaneously recorded for each subject. We used correlation and Bland-Altman analysis for comparing the parameters of HRV and PRV between two groups of children. Significant correlation (r > 0.90, p < 0.05) and close agreement were found between HRV and PRV for mean intervals, standard deviation of intervals (SDNN) and the root-mean square of the difference of successive intervals (RMSSD). However Bland-Altman analysis showed a large divergence for LF/HF ratio parameter. In addition, children with SDB had depressed SDNN and RMSSD and elevated LF/HF in comparison to children without SDB. In conclusion, PRV provides the accurate estimate of HRV in time domain analysis but does not reflect precise estimation for parameters in frequency domain. PMID:24111246

  13. Heart rate and heart rate variability in pregnant dairy cows and their fetuses determined by fetomaternal electrocardiography.

    Science.gov (United States)

    Trenk, Lisa; Kuhl, Juliane; Aurich, Jörg; Aurich, Christine; Nagel, Christina

    2015-11-01

    In this study, fetomaternal electrocardiograms were recorded once weekly in cattle during the last 14 weeks of gestation. From the recorded beat-to-beat (RR) intervals, heart rate and heart rate variability (HRV) variables standard deviation of the RR interval (SDRR) and root mean square of successive RR differences (RMSSD) were calculated. To differentiate between effects of lactation and gestation, pregnant lactating (PL) cows (n = 7) and pregnant nonlactating (PNL) heifers (n = 8) were included. We hypothesized that lactation is associated with stress detectable by HRV analysis. We also followed the hypothesis that heart rate and HRV are influenced by growth and maturation of the fetus toward term. Maternal heart rate changed over time in both groups, and in PL cows, it decreased with drying-off. During the last 5 weeks of gestation, maternal heart rate increased in both groups but was lower in PL cows than in PNL heifers. Maternal HRV did not change over time, but SDRR was significantly higher in PL cows than in PNL heifers, and significant interactions of group × time existed. On the basis of HRV, undisturbed pregnancies are thus no stressor for the dam in cattle. Fetal heart rate decreased from week 14 to week 1 before birth with no difference between groups. Gestational age thus determines heart rate in the bovine fetus. The HRV variables SDRR and RMSSD increased toward the end of gestation in fetuses carried by cows but not in those carried by heifers. The increase in HRV indicates maturation of fetal cardiac regulation which may be overrun by high sympathoadrenal activity in fetuses carried by heifers as suggested by their low HRV. PMID:26279313

  14. Heart rate variability and target organ damage in hypertensive patients

    Directory of Open Access Journals (Sweden)

    Melillo Paolo

    2012-11-01

    Full Text Available Abstract Background We evaluated the association between linear standard Heart Rate Variability (HRV measures and vascular, renal and cardiac target organ damage (TOD. Methods A retrospective analysis was performed including 200 patients registered in the Regione Campania network (aged 62.4?±?12, male 64%. HRV analysis was performed by 24-h holter ECG. Renal damage was assessed by estimated glomerular filtration rate (eGFR, vascular damage by carotid intima-media thickness (IMT, and cardiac damage by left ventricular mass index. Results Significantly lower values of the ratio of low to high frequency power (LF/HF were found in the patients with moderate or severe eGFR (p-value? Conclusions Depressed HRV appeared to be associated with vascular and renal TOD, suggesting the involvement of autonomic imbalance in the TOD. However, as the mechanisms by which abnormal autonomic balance may lead to TOD, and, particularly, to renal organ damage are not clearly known, further prospective studies with longitudinal design are needed to determine the association between HRV and the development of TOD.

  15. Inadequate control of heart rate in patients with stable angina: results from the European heart survey

    DEFF Research Database (Denmark)

    Daly, Caroline A; Clemens, Felicity; Sendon, Jose L Lopez; Tavazzi, Luigi; Boersma, Eric; Danchin, Nicolas; Delahaye, François; Gitt, Anselm; Julian, Desmond; Mulcahy, David; Ruzyllo, Witold; Thygesen, Kristian; Verheugt, Freek; Fox, Kim M

    2010-01-01

    AIMS: To examine resting heart rate (HR) in a population presenting with stable angina in relation to prior and subsequent pharmacological treatment, comorbid conditions and clinical outcome. METHODS AND RESULTS: The European Heart Survey was a prospective, observational, cohort study of 3779 patients with stable angina newly presenting to cardiology services. Mean baseline resting HR was 73 beats/min (bpm) and 52.3% of patients had a baseline HR > 70 bpm. Over half of patients were on no chrono...

  16. Association of Metabolic Syndrome With Exercise Capacity and Heart Rate Recovery in Patients With Coronary Heart Disease in the Heart and Soul Study

    OpenAIRE

    Spies, Christian; Otte, Christian; Kanaya, Alka; Pipkin, Sharon S.; Schiller, Nelson B.; WHOOLEY, MARY A.

    2005-01-01

    It is not known whether the metabolic syndrome is associated with poor exercise capacity among patients who have established coronary heart disease. We evaluated the association of the metabolic syndrome with treadmill exercise capacity and heart rate recovery among patients who had coronary heart disease. We measured treadmill exercise capacity (METs) and heart rate recovery (beats per minute) in 943 subjects who had known coronary heart disease. Of these, 377 (40%) had the metabolic syndrom...

  17. 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)

  18. Heart rate dynamics in different levels of Zen meditation.

    Science.gov (United States)

    Peressutti, Caroline; Martín-González, Juan M; M García-Manso, Juan; Mesa, Denkô

    2010-11-01

    The dynamic interactions among physiological rhythms imbedded in the heart rate signal can give valuable insights into autonomic modulation in conditions of reduced outward attention. Therefore, in this study we analyzed the heart rate variability (HRV) in different levels of practice in Zen meditation (Zazen). Nineteen subjects with variable experience took part in this study. In four special cases we collected both HRV and respiration data. The time series were analyzed in frequency domain and also using the Continuous Wavelet Transform, which detects changes in the time domain and in the frequency domain simultaneously. The shifts in the respiratory modulation of heart rate, or respiratory sinus arrhythmia (RSA), reflect the different levels of practice among practitioners with variable experience in Zazen; in turn the modulation of the RSA may reflect changes in the breathing pattern as in the parasympathetic outflow related to the quality and focus of attention in each stage. PMID:19631997

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

    Directory of Open Access Journals (Sweden)

    García-García Ángel

    2012-03-01

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

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

    Science.gov (United States)

    Nascimento, Bruno Ramos; Lima, Márcia Maria Oliveira; Nunes, Maria do Carmo Pereira; de Alencar, Maria Clara Noman; Costa, Henrique Silveira; Pinto Filho, Marcelo Martins; Cota, Vitor Emanuel Serafim; Rocha, Manoel Otávio da Costa; Ribeiro, Antonio Luiz Pinho

    2014-01-01

    Background: Heart rate variability (HRV) is a marker of autonomic dysfunction severity. The effects of physical training on HRV indexes in Chagas heart disease (CHD) are not well established. Objective: To evaluate the changes in HRV indexes in response to physical training in CHD. Methods: Patients with CHD and left ventricular (LV) dysfunction, physically inactive, were randomized either to the intervention (IG, N = 18) or control group (CG, N = 19). The IG participated in a 12-week exercise program consisting of 3 sessions/week. Results: Mean age was 49.5 ± 8 years, 59% males, mean LVEF was 36.3 ± 7.8%. Baseline HRV indexes were similar between groups. From baseline to follow-up, total power (TP): 1653 (IQ 625 - 3418) to 2794 (1617 - 4452) ms, p = 0.02) and very low frequency power: 586 (290 - 1565) to 815 (610 - 1425) ms, p = 0.047) increased in the IG, but not in the CG. The delta (post - pre) HRV indexes were similar: SDNN 11.5 ± 30.0 vs. 3.7 ± 25.1 ms. p = 0.10; rMSSD 2 (6 - 17) vs. 1 (21 - 9) ms. p = 0.43; TP 943 (731 - 3130) vs. 1780 (921 - 2743) Hz. p = 0.46; low frequency power (LFP) 1.0 (150 - 197) vs. 60 (111 - 146) Hz. p = 0.85; except for high frequency power, which tended to increase in the IG: 42 (133 - 92) vs. 79 (61 - 328) Hz. p = 0.08). Conclusion: In the studied population, the variation of HRV indexes was similar between the active and inactive groups. Clinical improvement with physical activity seems to be independent from autonomic dysfunction markers in CHD. PMID:25098373

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

    Directory of Open Access Journals (Sweden)

    Bruno Ramos Nascimento

    2014-09-01

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

  2. 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. Sign...

  3. 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.

  4. 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

  5. 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.

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

    DEFF Research Database (Denmark)

    Chreiteh, Shadi; Belhage, Bo; Hoppe, Karsten; Branebjerg, Jens; Thomsen, Erik Vilain

    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 reco...

  7. 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

  8. 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.

  9. Gonadal hormones and heart rate as an emotional response

    OpenAIRE

    Loos, Wolter Statius de,

    1988-01-01

    Animai experiments may give information on the physiology of hormones under stress conditions. The model for the investigation of acute emotional stress in animals that has been chosen permits the study of heart rate in freely moving laboratory rats as a sensitive psychophysiological parameter, This paradigm is usually described as passive avoidance behaviour. ... Zie: Summary

  10. Relationship between Exercise Heart Rate and Music Tempo Preference

    Science.gov (United States)

    Karageorghis, Costas I.; Jones, Leighton; Low, Daniel C.

    2006-01-01

    The present study examined the predicted positive and linear relationship (Iwanaga, 1995a, 1995b) between exercise heart rate and music tempo preference. Initially, 128 undergraduate students (M age = 20.0 years, SD = 0.9) were surveyed to establish their three favorite music artists. A separate experimental group of 29 undergraduates (M age =…

  11. Heart Rate Variability and Drawing Impairment in Hypoxemic COPD

    Science.gov (United States)

    Incalzi, Raffaele Antonelli; Corsonello, Andrea; Trojano, Luigi; Pedone, Claudio; Acanfora, Domenico; Spada, Aldo; D'Addio, Gianni; Maestri, Roberto; Rengo, Franco; Rengo, Giuseppe

    2009-01-01

    We studied 54 patients with hypoxemic chronic obstructive pulmonary disease (COPD). The Mini Mental State Examination and the Mental Deterioration Battery were used for neuropsychological assessment. Heart rate variability (HRV) was assessed based on 24-h Holter ECG recording. Mann-Whitney test was used to compare HRV parameters of patients…

  12. 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.

  13. Volitional Control of Heart Rate During Exercise Stress.

    Science.gov (United States)

    LeFevers, Victoria A.

    Thirty five volunteer college women were divided into three groups to determine if heart rate could be conditioned instrumentally and lowered during exercise stress on the treadmill. The three groups were a) experimental group I, 15 subjects who received instrumental conditioning with visual feedback; b) instrumental group II, 9 subjects who…

  14. 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…

  15. Exploring the Relationship between Fetal Heart Rate and Cognition

    Science.gov (United States)

    Kisilevsky, Barbara S.; Hains, Sylvia M. J.

    2010-01-01

    A relationship between fetal heart rate (HR) and cognition is explored within the context of infant, child and adult studies where the association is well established. Lack of direct access to the fetus and maturational changes limit research paradigms and response measures for fetal studies. Nevertheless, neural regulation of HR shows a number of…

  16. 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.

  17. A new physiological method for heart rate correction of the QT interval

    OpenAIRE

    Davey, P

    1999-01-01

    AIM—To reassess QT interval rate correction.?BACKGROUND—The QT interval is strongly and inversely related to heart rate. To compare QT intervals between different subjects with different heart rates requires the application of a QT interval rate correction formula. To date these formulae have inappropriately assumed a fixed relation between QT interval and heart rate. An alternative method of QT interval rate correction that makes no assumptions about the QT interval-heart rate relation is ne...

  18. Identifying Genetic Variants for Heart Rate Variability in the Acetylcholine Pathway

    Science.gov (United States)

    Riese, Harriëtte; Muñoz, Loretto M.; Hartman, Catharina A.; Ding, Xiuhua; Su, Shaoyong; Oldehinkel, Albertine J.; van Roon, Arie M.; van der Most, Peter J.; Lefrandt, Joop; Gansevoort, Ron T.; van der Harst, Pim; Verweij, Niek; Licht, Carmilla M. M.; Boomsma, Dorret I.; Hottenga, Jouke-Jan; Willemsen, Gonneke; Penninx, Brenda W. J. H.; Nolte, Ilja M.; de Geus, Eco J. C.; Wang, Xiaoling; Snieder, Harold

    2014-01-01

    Heart rate variability is an important risk factor for cardiovascular disease and all-cause mortality. The acetylcholine pathway plays a key role in explaining heart rate variability in humans. We assessed whether 443 genotyped and imputed common genetic variants in eight key genes (CHAT, SLC18A3, SLC5A7, CHRNB4, CHRNA3, CHRNA, CHRM2 and ACHE) of the acetylcholine pathway were associated with variation in an established measure of heart rate variability reflecting parasympathetic control of the heart rhythm, the root mean square of successive differences (RMSSD) of normal RR intervals. The association was studied in a two stage design in individuals of European descent. First, analyses were performed in a discovery sample of four cohorts (n?=?3429, discovery stage). Second, findings were replicated in three independent cohorts (n?=?3311, replication stage), and finally the two stages were combined in a meta-analysis (n?=?6740). RMSSD data were obtained under resting conditions. After correction for multiple testing, none of the SNPs showed an association with RMSSD. In conclusion, no common genetic variants for heart rate variability were identified in the largest and most comprehensive candidate gene study on the acetylcholine pathway to date. Future gene finding efforts for RMSSD may want to focus on hypothesis free approaches such as the genome-wide association study. PMID:25384021

  19. COMPARISON OF HEART RATE AND BLOOD PRESSURE CHANGES DURING WALKING AND RUNNING BEFORE AND AFTER TRAINING IN HEALTHY ADULT WOMEN

    Directory of Open Access Journals (Sweden)

    Kaarna Munisekhar

    2014-06-01

    Full Text Available AIM: Physical exercise has been associated with heart rate and blood pressure in observational studies and individual clinical trails. The purpose of these study was to asses heart rate and blood pressure changes in healthy adult women students before and after training during walking and running. MATERIALS and METHODS: Fourty healthy women were taken as the subjects. Heart rate and blood pressure recorded before and after training during waking and running. In these study 1600 metres track measured using PCV reel tape was used for walking and running. The durational training programme five months. Every day 15-20 minutes walking and running. RESULT: The examination at parameters BMI, Heart rate, Blood pressure, and SBP, DBP and study statistical analysis was estimated for all subjects. The data were analysed by disruptive and intervention studies. DISCUSION: The finding suggested a significant decrease in heart rate and blood pressure in healthy adult women after training as compared to before training for both during walking and running show that heart rate and blood pressure changes. CONCLUSION: The present study should that physical activity has the ability to decrease the heart rate and arterial blood pressure in healthy adult women. After training physical activity reduce the risk of heart diseases.

  20. Heart rate variability and target organ damage in hypertensive patients

    OpenAIRE

    Melillo Paolo; Izzo Raffaele; Luca De Nicola; Pecchia Leandro

    2012-01-01

    Abstract Background We evaluated the association between linear standard Heart Rate Variability (HRV) measures and vascular, renal and cardiac target organ damage (TOD). Methods A retrospective analysis was performed including 200 patients registered in the Regione Campania network (aged 62.4?±?12, male 64%). HRV analysis was performed by 24-h holter ECG. Renal damage was assessed by estimated glomerular filtration rate (eGFR), vascular damage by carotid intima-media thickness (IMT), and card...

  1. 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...

  2. 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 arrhyt...

  3. 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.

  4. Heart rate detection from an electronic weighing scale

    International Nuclear Information System (INIS)

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

  5. Skeletal muscle electrical stimulation improves baroreflex sensitivity and heart rate variability in heart failure rats.

    Science.gov (United States)

    Lazzarotto Rucatti, Ananda; Boemo Jaenisch, Rodrigo; Dalcin Rossato, Douglas; Poletto Bonetto, Jéssica Hellen; Ferreira, Janaína; Xavier, Leder Leal; Sonza, Anelise; Lago, Pedro Dal

    2015-12-01

    The goal of the current study was to evaluate the effects of electrical stimulation (ES) on the arterial baroreflex sensitivity (BRS) and cardiovascular autonomic control in rats with chronic heart failure (CHF). Male Wistar rats were designated to one of four groups: placebo sham (P-Sham, n=9), ES sham (ES-Sham, n=9), placebo CHF (P-CHF, n=9) or ES CHF (ES-CHF, n=9). The ES was adjusted at a low frequency (30Hz), duration of 250?s, with hold and rest time of 8s (4weeks, 30min/day, 5times/week). It was applied on the gastrocnemius muscle with intensity to produce a visible muscle contraction. The rats assigned to the placebo groups performed the same procedures with the equipment turned off. The two-way ANOVA and the post hoc Student-Newman-Keuls tests (Pheart rate sympatho-vagal modulation and peripheral sympathetic modulation in ES-CHF compared to P-CHF group. Interestingly, heart rate sympatho-vagal modulation was similar between ES-CHF and P-Sham groups. Thus, ES enhances heart rate parasympathetic modulation on heart failure (ES-CHF) compared to placebo (P-CHF), with consequent decrease of sympatho-vagal balance in the ES-CHF group compared to the P-CHF. The results show that a 4week ES protocol in CHF rats enhances arterial BRS and cardiovascular autonomic control. PMID:26433753

  6. Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography

    International Nuclear Information System (INIS)

    Background: Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. Purpose: To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. Material and Methods: Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. Results: Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR =65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. Conclusion: Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure

  7. Heart rate variability in rats acclimatized to high altitude.

    Science.gov (United States)

    Melin, Alexandre; Fauchier, Laurent; Dubuis, Eric; Obert, Philippe; Bonnet, Pierre

    2003-01-01

    The aims of this study were to relate heart morphology and functions changes to heart rate variability (HRV) components after acclimatization to high altitude and to define whether preadaptation to hypoxia could modulate HRV responses to acute hypoxic stress. Doppler-echocardiographic studies of the left ventricle were performed in female Wistar rats before, during, and after a 10-week exposure to moderate hypobaric hypoxia (CH rats, approximately 4000 m simulated) or normoxia (N rats, approximately 55 m). Right ventricular morphology and function and pulmonary artery pressure were evaluated using heart catheterization. Spectral analysis of HRV was studied after exposure in conscious unrestrained rats in normoxia and during acute hypoxic stress. Necropsy right ventricular hypertrophy and intraventricular and pulmonary artery hypertension were found in CH rats compared with N rats. Echocardiographic left ventricular morphology and functions were similar between the groups after exposures. Compared to the control group, CH rats had similar heart rates and HRV components when measured in normoxia. During acute hypoxic stress, HRV decreased in all rats, but less in CH rats. These results support the hypothesis that long-term mild hypoxia may moderate sympathetic activation induced by acute hypoxia and that right ventricular hypertrophy cannot be the direct cause of such a shift in sympathovagal nerve interaction during acute hypoxic stress. PMID:14561243

  8. 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

  9. 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.

  10. Analysis of the work rates and heart rates of association football referees.

    OpenAIRE

    Catterall, C; Reilly, T; Atkinson, G.; Coldwells, A

    1993-01-01

    This study aimed to describe the work-rate profiles of referees during soccer matches and record heart-rate responses during these games. Using video-recordings 14 referees were observed and their heart rates during the games were monitored by short-range radio telemetry. These included 11 football league matches. The exercise intensity was largely submaximal with a change in activity every 6 s. The mean distance covered during the game was 9.44 km; a significant fall in work rate was noted i...

  11. Analysis of the work rates and heart rates of association football referees.

    Science.gov (United States)

    Catterall, C; Reilly, T; Atkinson, G; Coldwells, A

    1993-09-01

    This study aimed to describe the work-rate profiles of referees during soccer matches and record heart-rate responses during these games. Using video-recordings 14 referees were observed and their heart rates during the games were monitored by short-range radio telemetry. These included 11 football league matches. The exercise intensity was largely submaximal with a change in activity every 6 s. The mean distance covered during the game was 9.44 km; a significant fall in work rate was noted in the second half (P top level soccer places high physiological demands on the official. This has implications for training and fitness assessment. PMID:8242278

  12. Heart Rate Variability: A Risk Factor for Female Sexual Dysfunction.

    Science.gov (United States)

    Stanton, Amelia M; Lorenz, Tierney A; Pulverman, Carey S; Meston, Cindy M

    2015-09-01

    Heart rate variability (HRV) is a measure of autonomic nervous system activity, which reflects an individual's ability to adapt to physiological and environmental changes. Low resting HRV has been linked to several mental health conditions, including depression, anxiety, and alcohol dependence (Kemp et al. in Biological Psychiatry 67(11):1067-1074, 2010. doi:10.1016/j.biopsych.2009.12.012; Kemp et al. in PloS One, 7(2):e30777, 2012; Quintana et al. in Drug and Alcohol Dependence, 132(1-2):395-398, 2013. doi:10.1016/j.drugalcdep.2013.02.025). HRV has also been used as a method for indexing the relative balance of sympathetic nervous system (SNS) activity to parasympathetic nervous system activity. This balance-in particular, moderately dominant SNS activity-has been shown to play a significant role in women's genital sexual arousal in the laboratory; however, the role of SNS activity in clinically relevant sexual arousal function is unknown. The present study assessed the feasibility of using HRV as an index of women's self-reported sexual arousal function outside the laboratory. Sexual arousal function, overall sexual function, and resting HRV were assessed in 72 women, aged 18-39. Women with below average HRV were significantly more likely to report sexual arousal dysfunction (p < .001) and overall sexual dysfunction (p < .001) than both women with average HRV and women with above average HRV. In conclusion, low HRV may be a risk factor for female sexual arousal dysfunction and overall sexual dysfunction. PMID:26081002

  13. Associations Between Insulin and Heart Rate Variability in Police Officers

    Science.gov (United States)

    Charles, Luenda E.; Andrew, Michael E.; Sarkisian, Khachatur; Li, Shengqiao; Mnatsakanova, Anna; Violanti, John M.; Wilson, Mark; Gu, Ja K.; Miller, Diane B.; Burchfiel, Cecil M.

    2015-01-01

    Objective Low heart rate variability (HRV) has been linked to cardiovascular disease. Our objective was to examine the cross-sectional association between insulin and HRV. Methods Insulin levels were measured in 355 nondiabetic officers from the BCOPS study, following a 12 h fast. HRV was performed according to methods published by the task force of the European Society of Cardiology and the North American Society of Pacing Electrophysiology for measurement and analysis of HRV. Mean values of high (HF) and low frequency (LF) HRV were compared across tertiles of insulin using ANOVA and ANCOVA; p-values were obtained from linear regression models. Results Higher mean levels of insulin were significantly associated with lower (i.e., worse) mean levels of HRV before and after risk-factor adjustment. The results for HF HRV (ms2) were as follows: 1st insulin (µU/ml) tertile (156.3; 95% confidence interval (CI) = 128.6–189.9); 2nd tertile (154.3; 95% CI = 124.3–191.5); 3rd tertile (127.9; 95% CI = 105.0–155.8), p for trend = 0.017. Results with LF HRV were similar to HF HRV. Insulin was also inversely and significantly associated with HRV among officers with BMI ?25 kg/m2, with ?25.5% body fat, and among those who reported low (physical activity scores. Conclusions In this cohort, insulin levels were inversely and significantly associated with both HF and LF HRV, especially among those with higher levels of obesity and lower levels of physical activity, suggesting associations with autonomic nervous system function. Prospective studies of this association in other populations are warranted. PMID:24136902

  14. 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)

  15. gHRV: Heart rate variability analysis made easy.

    Science.gov (United States)

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

    2014-08-01

    In this paper, the gHRV software tool is presented. It is a simple, free and portable tool developed in python for analysing heart rate variability. It includes a graphical user interface and it can import files in multiple formats, analyse time intervals in the signal, test statistical significance and export the results. This paper also contains, as an example of use, a clinical analysis performed with the gHRV tool, namely to determine whether the heart rate variability indexes change across different stages of sleep. Results from tests completed by researchers who have tried gHRV are also explained: in general the application was positively valued and results reflect a high level of satisfaction. gHRV is in continuous development and new versions will include suggestions made by testers. PMID:24854108

  16. 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.

  17. 256-slice CT coronary angiography in atrial fibrillation: The impact of mean heart rate and heart rate variability on image quality

    Science.gov (United States)

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

    2011-08-01

    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.MaterialsAll 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.ResultsNo 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.ConclusionThis 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.

  18. 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.

  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 examinations.

  20. Scaling and Ordering of Neonatal Heart Rate Variability

    Science.gov (United States)

    Aghili, Ali A.; Rizwan-Uddin, Rizwan-Uddin; Griffin, M. Pamela; Moorman, J. Randall

    1995-02-01

    By analyzing cardiac beat-to-beat intervals and interbeat increments, we find that-unlike adults-the difference in the pattern of interbeat increments in healthy and sick newborn infants is more due to a change in the amplitude and much less to a change in the ordering of the interbeat increments. This suggests that very low-frequency elements of neonatal and adult heart rate variability rise from fundamentally different mechanisms.

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

    OpenAIRE

    Kheder, G.; Kachouri, A.; M. Ben Massoued; 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 ...

  2. Multiscale analysis of heart rate variability in nonstationary environments

    OpenAIRE

    BrianM.Gurbaxani; JianboGao; KeriJ.Heilman; GregoryF.Lewis

    2013-01-01

    Heart rate variability (HRV) is highly nonstationary, even if no perturbing influences can be identified during the recording of the data. The nonstationarity becomes more profound when HRV data are measured in intrinsically nonstationary environments, such as social stress. In general, HRV data measured in such situations are more difficult to analyze than those measured in constant environments. In this paper, we analyze HRV data measured during a social stress test using two multiscale ap...

  3. Development of a heart rate variability analysis tool

    OpenAIRE

    Medeiros, José Miguel

    2010-01-01

    Heart Rate Variability (HRV) concerns the analysis of the phenomenon underlying the variability between consecutive heartbeats. During the last three decades, significant effort has been made to understand its physiological basis and implications in different pathologies. Such studies have revealed, among other aspects, that HRV its a mirror of the control actions exerted by the Autonomic Nervous System (ANS) in the Sinoatrial (SA) node. Since the SA node is responsible for set...

  4. Clinical Application of Heart Rate Variability after Acute Myocardial Infarction

    OpenAIRE

    HeikkiVeliHuikuri; PhyllisKravetStein

    2012-01-01

    Abstract Heart rate (HR) variability has been extensively studied in patients surviving an acute myocardial infarction (AMI). The majority of studies have shown that patients with reduced or abnormal HR variability/turbulence have an increased risk of mortality within few years after an AMI. Various measures of HR dynamics, such as time-domain, spectral, and non-linear measures of HR variability, as well as HR turbulence, have been used in risk stratification of post-AMI patients. The prog...

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

    DEFF Research Database (Denmark)

    Fisher, James P; Adlan, Ahmed M; Shantsila, Alena; Secher, J Frederik; Sørensen, Henrik; Secher, Niels H

    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 dru...

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

    DEFF Research Database (Denmark)

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

    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...

  7. Effect of meditation on scaling behavior and complexity of human heart rate variability

    CERN Document Server

    Sarkar, A

    2006-01-01

    The heart beat data recorded from samples before and during meditation are analyzed using two different scaling analysis methods. These analyses revealed that mediation severely affects the long range correlation of heart beat of a normal heart. Moreover, it is found that meditation induces periodic behavior in the heart beat. The complexity of the heart rate variability is quantified using multiscale entropy analysis and recurrence analysis. The complexity of the heart beat during mediation is found to be more.

  8. Effect of meditation on scaling behavior and complexity of human heart rate variability

    OpenAIRE

    Sarkar, A.; Barat, P.

    2006-01-01

    The heart beat data recorded from samples before and during meditation are analyzed using two different scaling analysis methods. These analyses revealed that mediation severely affects the long range correlation of heart beat of a normal heart. Moreover, it is found that meditation induces periodic behavior in the heart beat. The complexity of the heart rate variability is quantified using multiscale entropy analysis and recurrence analysis. The complexity of the heart beat...

  9. Heart rate variability and baroreceptor responsiveness to evaluate autonomic cardiovascular adaptations to exercise

    Directory of Open Access Journals (Sweden)

    WILLIAM H. COOKE

    Full Text Available Exercise physiologists routinely evaluate adaptations to exercise such as aerobic capacity, muscular strength and flexibility, and body composition, but often overlook the effects of exercise training on autonomic regulation of cardiovascular function. A preponderance of cross-sectional studies report significant resting sinus bradycardia and high heart rate variability in active subjects, and suggest that exercise training induces adaptations in autonomic cardiovascular control. Alternatively, data from cross-sectional studies leave open the possibility that individuals with a genetic predisposition for lower heart rates or greater heart rate variability are also endowed with greater aerobic capacity. Conflicting results from a limited number of exercise training studies fail to conclusively demonstrate a direct effect of exercise training on the autonomic nervous system. In this report I suggest that simple measures of heart rate variability during controlled frequency breathing, and arterial baroreceptor responsiveness to Valsalva's maneuver provide unique insights into autonomic regulation of cardiovascular function. I propose that systemic-wide integration of exercise training effects might be better characterized if exercise physiologists would perform tests of autonomic function in conjunction with standard exercise tests during routine laboratory evaluations.

  10. In Rare Cases, Hepatitis C Drug Tied to Slowed Heart Rate

    Science.gov (United States)

    ... Rare Cases, Hepatitis C Drug Tied to Slowed Heart Rate: Study But experts say these types of medications ... C can cause a very slow and erratic heart rate in some patients, new research warns. Doctors at ...

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

    OpenAIRE

    Lakusic, Nenad; Mahovic, Darija; Kruzliak, Peter; 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 my...

  12. Mobilisation readiness state and the frequency structure of heart rate variability

    OpenAIRE

    Mukhin, V.; Klimenko, V.

    2010-01-01

    A number of studies showed association of mental status with heart rate variability. This work discovered a feature of frequency structure of heart rate variability that is associated with mental readiness. In three independent groups of 64, 39, and 19 volunteers by the factor analysis of heart rate periodograms, it has been discovered that there are at least two other heart rate oscillation phenomena apart from the well known low frequency oscillations and respiratory arrhy...

  13. 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 cardio...

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

    Scientific Electronic Library Online (English)

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

    Full Text Available 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 hear [...] t 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 exercise test. METHODS: Twenty-five heart failure patients (49±11 years, 76% male), with an average LVEF of 30±7%, and fourteen controls were included in the study. Patients with atrial fibrillation, a pacemaker or noncardiovascular functional limitations or whose drug therapy was not optimized were excluded. Optimization was considered to be 50 mg/day or more of carvedilol, with a basal heart rate between 50 to 60 bpm that was maintained for 3 months. RESULTS: Basal heart rate was lower in heart failure patients (57±3 bpm) compared to controls (89±14 bpm; p

  15. 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 identify new therapeutic targets.

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

    Science.gov (United States)

    den Hoed, Marcel; Eijgelsheim, Mark; Esko, Tõnu; Brundel, Bianca J J M; Peal, David S; Evans, David M; Nolte, Ilja M; Segrè, Ayellet V; Holm, Hilma; Handsaker, Robert E; Westra, Harm-Jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia; Zhao, Jing Hua; Kim, Young Jin; Go, Min Jin; Almgren, Peter; Bochud, Murielle; Boucher, Gabrielle; Cornelis, Marilyn C; Gudbjartsson, Daniel; Hadley, David; Van Der Harst, Pim; Hayward, Caroline; Heijer, Martin Den; Igl, Wilmar; Jackson, Anne U; Kutalik, Zoltán; Luan, Jian’an; Kemp, John P; Kristiansson, Kati; Ladenvall, Claes; Lorentzon, Mattias; Montasser, May E; Njajou, Omer T; O’Reilly, Paul F; Padmanabhan, Sandosh; Pourcain, Beate St.; Rankinen, Tuomo; Salo, Perttu; Tanaka, Toshiko; Timpson, Nicholas J; Vitart, Veronique; Waite, Lindsay; Wheeler, William; Zhang, Weihua; Draisma, Harmen H M; Feitosa, Mary F; Kerr, Kathleen F; Lind, Penelope A; Mihailov, Evelin; Onland-Moret, N Charlotte; Song, Ci; Weedon, Michael N; Xie, Weijia; Yengo, Loic; Absher, Devin; Albert, Christine M; Alonso, Alvaro; Arking, Dan E; de Bakker, Paul I W; Balkau, Beverley; Barlassina, Cristina; Benaglio, Paola; Bis, Joshua C; Bouatia-Naji, Nabila; Brage, Søren; Chanock, Stephen J; Chines, Peter S; Chung, Mina; Darbar, Dawood; Dina, Christian; Dörr, Marcus; Elliott, Paul; Felix, Stephan B; Fischer, Krista; Fuchsberger, Christian; de Geus, Eco J C; Goyette, Philippe; Gudnason, Vilmundur; Harris, Tamara B; Hartikainen, Anna-liisa; Havulinna, Aki S; Heckbert, Susan R; Hicks, Andrew A; Hofman, Albert; Holewijn, Suzanne; Hoogstra-Berends, Femke; Hottenga, Jouke-Jan; Jensen, Majken K; Johansson, Åsa; Junttila, Juhani; Kääb, Stefan; Kanon, Bart; Ketkar, Shamika; Khaw, Kay-Tee; Knowles, Joshua W; Kooner, Angrad S; Kors, Jan A; Kumari, Meena; Milani, Lili; Laiho, Päivi; Lakatta, Edward G; Langenberg, Claudia; Leusink, Maarten; Liu, Yongmei; Luben, Robert N; Lunetta, Kathryn L; Lynch, Stacey N; Markus, Marcello R P; Marques-Vidal, Pedro; Leach, Irene Mateo; McArdle, Wendy L; McCarroll, Steven A; Medland, Sarah E; Miller, Kathryn A; Montgomery, Grant W; Morrison, Alanna C; Müller-Nurasyid, Martina; Navarro, Pau; Nelis, Mari; O’Connell, Jeffrey R; O’Donnell, Christopher J; Ong, Ken K; Newman, Anne B; Peters, Annette; Polasek, Ozren; Pouta, Anneli; Pramstaller, Peter P; Psaty, Bruce M; Rao, Dabeeru C; Ring, Susan M; Rossin, Elizabeth J; Rudan, Diana; Sanna, Serena; Scott, Robert A; Sehmi, Jaban S; Sharp, Stephen; Shin, Jordan T; Singleton, Andrew B; Smith, Albert V; Soranzo, Nicole; Spector, Tim D; Stewart, Chip; Stringham, Heather M; Tarasov, Kirill V; Uitterlinden, André G; Vandenput, Liesbeth; Hwang, Shih-Jen; Whitfield, John B; Wijmenga, Cisca; Wild, Sarah H; Willemsen, Gonneke; Wilson, James F; Witteman, Jacqueline C M; Wong, Andrew; Wong, Quenna; Jamshidi, Yalda; Zitting, Paavo; Boer, Jolanda M A; Boomsma, Dorret I; Borecki, Ingrid B; Van Duijn, Cornelia M; Ekelund, Ulf; Forouhi, Nita G; Froguel, Philippe; Hingorani, Aroon; Ingelsson, Erik; Kivimaki, Mika; Kronmal, Richard A; Kuh, Diana; Lind, Lars; Martin, Nicholas G; Oostra, Ben A; Pedersen, Nancy L; Quertermous, Thomas; Rotter, Jerome I; van der Schouw, Yvonne T; Verschuren, W M Monique; Walker, Mark; Albanes, Demetrius; Arnar, David O; Assimes, Themistocles L; Bandinelli, Stefania; Boehnke, Michael; de Boer, Rudolf A; Bouchard, Claude; Caulfield, W L Mark; Chambers, John C; Curhan, Gary; Cusi, Daniele; Eriksson, Johan; Ferrucci, Luigi; van Gilst, Wiek H; Glorioso, Nicola; de Graaf, Jacqueline; Groop, Leif; Gyllensten, Ulf; Hsueh, Wen-Chi; Hu, Frank B; Huikuri, Heikki V; Hunter, David J; Iribarren, Carlos; Isomaa, Bo; Jarvelin, Marjo-Riitta; Jula, Antti; Kähönen, Mika; Kiemeney, Lambertus A; van der Klauw, Melanie M; Kooner, Jaspal S; Kraft, Peter; Iacoviello, Licia; Lehtimäki, Terho; Lokki, Marja-Liisa L; Mitchell, Braxton D; Navis, Gerjan; Nieminen, Markku S; Ohlsson, Claes; Poulter, Neil R; Qi, Lu; Raitakari, Olli T; Rimm, Eric B; Rioux, John D; Rizzi, Federica; Rudan, Igor; Salomaa, Veikko; Sever, Peter S; Shields, Denis C; Shuldiner, Alan R; Sinisalo, Juha; Stanton, Alice V; Stolk, Ronald P; Strachan, David P; Tardif, Jean-Claude; Thorsteinsdottir, Unnur; Tuomilehto, Jaako; van Veldhuisen, Dirk J; Virtamo, Jarmo; Viikari, Jorma; Vollenweider, Peter; Waeber, Gérard; Widen, Elisabeth; Cho, Yoon Shin; Olsen, Jesper V; Visscher, Peter M; Willer, Cristen; Franke, Lude; Erdmann, Jeanette; Thompson, John R; Pfeufer, Arne; Sotoodehnia, Nona

    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 identify new therapeutic targets. PMID:23583979

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

    Science.gov (United States)

    Branco, Braulio H.M.; Massuça, Luis M.; Andreato, Leonardo V.; Marinho, Bruno F.; Miarka, Bianca; Monteiro, Luis; Franchini, Emerson

    2013-01-01

    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. PMID:23802054

  18. 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

  19. Self-rating level of perceived exertion for guiding exercise intensity during a 12-week cardiac rehabilitation programme and the influence of heart rate reducing medication

    DEFF Research Database (Denmark)

    Tang, Lars H; Zwisler, Ann-Dorthe

    2015-01-01

    OBJECTIVES: To investigate whether self-rating level of perceived exertion can adequately guide exercise intensity during a 12-week cardiac rehabilitation programme. DESIGN: Linear regression analysis using rehabilitation data from two randomised controlled trials. METHODS: Patients undergoing radiofrequency ablation for atrial fibrillation or following heart valve surgery and participating in exercise-based rehabilitation were included. The 12-week rehabilitation outpatient programme comprised three weekly training sessions, each consisting of 20min aerobic exercise divided into three steps. Patients were asked to base their exercise intensity for each step on a predefined rating of perceived exertion specified in a training diary. Exercise intensity was objectively measured by heart rate during the last 2min for each exercise step. Comparative analysis and linear regression of the rating of perceived exertion and heart rate were performed. RESULTS: A total of 2622 ratings of perceived exertion were collected from 874 training sessions in 97 patients. Heart rate and rating of perceived exertion were associated both across all three exercise steps and individually for each step, with a mean of 6 to7bpm per 1-point difference in the rating of perceived exertion (p<0.001). Adjusting for rate-reducing medication slightly improved the strength of the association. CONCLUSIONS: The association between change in the rating of perceived exertion and change in heart rate indicates that a diary-led and self-regulated model using rating of perceived exertion can help guide exercise intensity in everyday clinical practice among patients with heart disease, irrespective if they are taking heart rate-reducing medication.

  20. 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…

  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. 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…

  3. Respiratory modulation and baroreflex control of heart rate in space

    Science.gov (United States)

    Verheyden, Bart; Couckuyt, Kurt; Liu, Jiexin; Aubert, Andre

    During everyday life, gravity constantly stresses the human circulation by diminishing venous return in the upright position. This induces baroreflex-mediated cardiovascular adjustments that are aimed to prevent the blood pressure from falling. In weightlessness, gravitational pressure gradients do not arise in the circulation so that baroreflex function remains chronically unchallenged. This may contribute to the development of post spaceflight orthostatic intolerance. The purpose of this study was to evaluate respiratory modulation and baroreflex control of heart rate after a week of weightlessness in space. We tested the hypothesis that cardiovascular control in space will be similar to the baseline supine condition on Earth. We studied nine male cosmonauts during seven different space missions aboard the ISS (age 40 - 52 yrs, height 1.69 - 1.85 m, weight 67 - 90 kg). Data collection was performed between 30 and 45 days before launch in the standing and supine positions, and after 8 days in space. Cosmonauts were carefully trained to perform in-flight data collection by themselves. They were instructed to pace their breathing to a fixed rate of 12 breaths per minute (0.2 Hz) for a total duration of 3 minutes. The electrocardiogram and beat-by-beat finger arterial blood pressure were recorded at 1-kHz sample rate. Respiratory rate was evaluated using an abdominal pressure sensor. We used power spectral analysis to calculate respiratory sinus arrhythmia (RSA) as well as the low-frequency (0.04 - 0.15 Hz) powers of spontaneous oscillations in heart rate and systolic blood pressure. Baroreflex sensitivity (BRS) was estimated in the time domain using cross-correlation analysis. As expected, there was a rise in heart rate upon assuming the standing position before space- flight (59 ± 6 to 79 ± 11 beats per min; p ¡ 0.001). This was accompanied by an increase in mean arterial blood pressure (84 ± 6 to 93 ± 6 mmHg; p ¡ 0.001). Standing up further induced a marked increase in the low-frequency powers of systolic blood pressure oscillations (8 ± 7 to 17 ± 11 mmHg2; p = 0.018), whereas those in heart rate remained unchanged (445 ± 512 to 621 ± 799 ms2; p = 0.315). Alternatively, there was a reduction in RSA from 546 ± 167 ms2 to 158 ± 298 ms2 and in spontaneous BRS from 14 ± 5 ms/mmHg to 6 ± 2 ms/mmHg upon changing from supine to standing (both p ¡ 0.001). After a week of weightlessness in space, heart rate (61 ± 8 beats per min) and mean blood pressure (83 ± 6 mmHg) returned to the pre-flight supine values. This was also true for the low-frequency powers of systolic blood pressure (7 ± 4 mmHg2) and of heart rate (741 ± 716 ms2), as well as for RSA (465 ± 269 ms2) and spontaneous BRS (14 ± 4 ms/mmHg). It is concluded that cardiovascular control after one week in space corresponds to the pre-flight supine condition. This is characterized by a chronically increased vagal-cardiac outflow and suppressed sympathetic vasomotor modulation compared with the standing position on Earth. This kind of chronic baroreflex unloading is likely to contribute to post-spaceflight functional impairment of orthostatic blood pressure control.

  4. 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.

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

    DEFF Research Database (Denmark)

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

    1996-01-01

    OBJECTIVES: The purpose of the study was to investigate the short- and long-term variations in the non-linear dynamics of heart rate variability, and to determine the relationships between conventional time and frequency domain methods and the newer non-linear methods of characterizing heart rate variability. METHODS: Twelve healthy subjects were investigated by 3-h ambulatory ECG recordings repeated on 3 separate days. Correlation dimension, non-linear predictability, mean heart rate, and heart...

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

    OpenAIRE

    Souvik Das

    2014-01-01

    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: sym...

  7. Prognostic value of the exercise heart rates in the stress myocardial perfusion imaging on cardiac events

    International Nuclear Information System (INIS)

    Full text: Objectives: To evaluate the clinical value of the exercise heart rate (HR) in the stress myocardial perfusion imaging (MPI) and cardiac events (CE). Methods: All pts underwent exercise MPI after symptom-limited exercise treadmill testing by Bruce protocol. Heart rate, blood pressure, and 3- lead ECGS were recorded during exercise. The mean interval of following up was 29.75±9.73 (1?27) months. The mean stress amount was 3.79±0.93 (2-6) degrees, and the mean lasted time was 14.80±2.42 (6-20) minutes. Results: A total number of 346 pts (233 M/113 F; mean age 51.73±9.88 years). According to the exercise HR reached submaximal dose or not, the pts were divided into G1 (n=294, HR reached submaximal dose) and G2 (n=52, HR didn't reach submaximal dose). Over all, there were 85 pts with positive MPI in G1, but only 22 pts in G2 (Pearson chisquare 9.018, P < 0.05). The rate of CE occurrence in G1 and G2 is 2.7% and 17.3% respectively (Pearson chisquare20.123, P <0.05). The positive MPI result and the rate of CE in G2 were higher than G1. Conclusions: In the exercise MPI, the heart rate which don't reach submaximal dose may predict the presence of abnormal MPI and subsequent CE. (author)

  8. Day-to-night time differences in the relationship between cardiorespiratory coordination and heart rate variability

    International Nuclear Information System (INIS)

    Heart rate variability (HRV) and cardiorespiratory coordination, i.e. the temporal interplay between oscillations of heartbeat and respiration, reflect information related to the cardiovascular and autonomic nervous system. The purpose of this study was to investigate the relationship between spectral measures of HRV and measures of cardiorespiratory coordination. In 127 subjects from a normal population a 24 h Holter ECG was recorded. Average heart rate (HR) and the following HRV parameters were calculated: very low (VLF), low (LF) and high frequency (HF) oscillations and LF/HF. Cardiorespiratory coordination was quantified using average respiratory rate (RespR), the ratio of heart rate and respiratory rate (HRR), the phase coordination ratio (PCR) and the extent of cardiorespiratory coordination (PP). Pearson's correlation coefficient r was used to quantify the relationship between each pair of the variables across all subjects. HR and HRR correlated strongest during daytime (r = 0.89). LF/HF and PP showed a negative correlation to a reasonable degree (r = ?0.69). During nighttime sleep these correlations decreased whereas the correlation between HRR and RespR (r = ?0.47) as well as between HRR and PCR (r = 0.73) increased substantially. In conclusion, HRR and PCR deliver considerably different information compared to HRV measures whereas PP is partially linked reciprocally to LF/HF

  9. 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.

  10. Heart rate variability helps tracking time more accurately.

    Science.gov (United States)

    Cellini, Nicola; Mioni, Giovanna; Levorato, Ilenia; Grondin, Simon; Stablum, Franca; Sarlo, Michela

    2015-12-01

    Adequate temporal abilities are crucial for adaptive behavior. In time processing, variations in the rate of pulses' emission by the pacemaker are often reported to be an important cause of temporal errors. These variations are often associated with physiological changes, and recently it has also been proposed that physiological changes may not just vary the pulses' emission, but they can work as a timekeeper themselves. In the present study we further explore the relationship between temporal abilities with autonomic activity and interoceptive awareness in a group of thirty healthy young adults (mean age 24.18years; SD=2.1). Using electrocardiogram, impedance cardiography and skin conductance measures, we assessed the relationship between the autonomic profile at rest and temporal abilities in two temporal tasks (time bisection and finger tapping tasks). Results showed that heart rate variability affects time perception. We observed that increased heart rate variability (HRV) was associated with higher temporal accuracy. More specifically, we found that higher vagal control was associated with lower error in producing 1-s tempo, whereas higher overall HRV was related with lower error (measured by the constant error) in the time bisection task. Our results support the idea that bodily signals may shape our perception of time. PMID:26507899

  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. Peak heart rate decreases with increasing severity of acute hypoxia

    DEFF Research Database (Denmark)

    Lundby, C; Araoz, M; Van Hall, Gerrit

    2001-01-01

    The purpose of the present study was to investigate the degree to which peak heart rate is reduced during exhaustive exercise in acute hypoxia. Five sea-level lowlanders performed maximal exercise at normobaric normoxia and at three different levels of hypobaric hypoxia (barometric pressures of 518, 459, and 404 mmHg) in a hypobaric chamber and while breathing 9% O(2) in N(2). These conditions were equivalent to altitudes of 3300, 4300, 5300, and 6300 m above sea level, respectively. At 4300 m, ...

  13. Correlated and uncorrelated heart rate fluctuations during relaxing visualization

    Science.gov (United States)

    Papasimakis, N.; Pallikari, F.

    2010-05-01

    The heart rate variability (HRV) of healthy subjects practicing relaxing visualization is studied by use of three multiscale analysis techniques: the detrended fluctuation analysis (DFA), the entropy in natural time (ENT) and the average wavelet (AWC) coefficient. The scaling exponent of normal interbeat interval increments exhibits characteristics of the presence of long-range correlations. During relaxing visualization the HRV dynamics change in the sense that two new features emerge independent of each other: a respiration-induced periodicity that often dominates the HRV at short scales (correlations. These characteristics have been previously seen in the HRV dynamics during non-REM sleep.

  14. 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.

  15. Alpha-linolenic acid and heart rate variability

    DEFF Research Database (Denmark)

    Christensen, Jeppe Hagstrup; Christensen, MS; Toft, E; Dyerberg, J; Schmidt, Erik Berg

    2000-01-01

    BACKGROUND AND AIM: The marine long-chained n-3 polyunsaturated fatty acids seem to have antiarrhythmic effects in humans. Similar effect has also been postulated for alpha-linolenic acid, a plant-derived polyunsaturated fatty acid--from the n-3 family. The purpose of the study was to examine the relation between the content of alpha-linolenic acid in cell membranes and the risk of malignant arrhythmias as assessed by determination of heart rate variability (HRV). METHODS AND RESULTS: Patients a...

  16. Decreased heart rate variability in surgeons during night shifts

    DEFF Research Database (Denmark)

    Amirian, Ilda; Toftegård Andersen, Lærke; Rosenberg, Jacob; Gögenur, Ismail

    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....

  17. 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.

  18. Role of GABAA receptors of bed nucleus stria terminalis in controlling of blood pressure and heart rate in rats

    Directory of Open Access Journals (Sweden)

    Maesoumeh Hatam

    2007-03-01

    Full Text Available Introduction: The Bed nucleus stria terminalis (BST is a part of the limbic system. It was recently shown that chemical stimulation of the BST by L-glutamate elicited cardiovascular depressive responses. In the present study, we have investigated the possible cardiovascular role of the GABAergic receptors in BST by microinjection of its agonist and antagonists. Methods: Experiments were performed on 21 anaesthetized rats. Drugs were microinjected into the BST in volume of 50 nl using streotaxic apparatus. Blood pressure and heart rate were recorded before and throughout each experiment. The averages of maximum changes in the arterial pressure and heart rate were compared with control group and with its average in before injections using student t-test and paired t-test, respectively. Results: GABAA receptor antagonist, bicuculline met iodide (BMI, 1 mM, increased both arterial pressure (+14.2±3.08 and heart rate (+9.8± 2.5 (p<0.05. Muscimole, a GABAA agonist (5 mM, caused a significant decrease of the arterial pressure (-10.2 ±4.1 and heart rate (-20.3±9.40 (p<0.01. However, microinjection of phaclofen (5 mM, a GABAB receptor antagonist caused small unsignificant changes of the heart rate and blood pressure. Conclusion: GABAergic inhibitory neurons of the BST seems to cause decrease in the blood pressure and heart rate by GABAA but not GABAB receptors.

  19. Unobtrusive heart rate monitor based on a fiber specklegram sensor and a single-board computer

    Science.gov (United States)

    Benevides, Alessandro B.; Frizera, Anselmo; Cotrina, Anibal; Ribeiro, Moisés. R. N.; Segatto, Marcelo E. V.; Pontes, Maria José

    2015-09-01

    This paper proposes a portable and unobtrusive heart rate monitor based on fiber specklegram sensors. The proposed module uses the Raspberry Pi module to perform the image acquisition and the fiber specklegram sensor, which is based on multimode plastic optical fibers. The heart rate is obtained by welch power spectral density estimate and the heart beats are identified by means of a threshold analysis.

  20. High-dose intravenous metoprolol usage for reducing heart rate at CT coronary angiography: Efficacy and safety

    International Nuclear Information System (INIS)

    Aim: To evaluate the usage, safety, and efficacy of high-dose intravenous metoprolol for heart rate reduction in computer tomographic (CT) coronary angiography. Materials and methods: As this was retrospective analysis of anonymous data, medical ethics committee approval was waived by the regional health research authority. Patients, who had known iodinated contrast medium allergy, contraindications to ?-blockers, atrial fibrillation, and indications other than suspected coronary artery disease, were excluded from analysis. The ultimate study population of 662 were analysed with details of intravenous metoprolol doses, complications, heart rate before administration of intravenous metoprolol (resting heart rate, RHR), heart rate at acquisition of scan (acquisition heart rate, AHR), and usage of low radiation dose protocols. Results: Of the ultimate study population of 662 patients, 183 had no intravenous metoprolol with mean acquisition heart rate (AHR) of 58 beats per minute (bpm), 257 had 1–15 mg intravenous metoprolol with mean AHR of 57 bpm, 114 had 16–29 mg intravenous metoprolol with mean AHR of 62 bpm and 108 had ?30 mg intravenous metoprolol with mean AHR of 66 bpm. In the group receiving intravenous metoprolol, average usage was 19 mg (maximum 67 mg) with average reduction in HR of 15 bpm. There were no clinical incidents in relation to the use of high-dose intravenous metoprolol. Conclusion: Higher doses of intravenous metoprolol are beneficial in achieving target heart rates to facilitate usage of low radiation dose protocols. With appropriate exclusion criteria, higher doses of intravenous metoprolol, well in excess of 15 mg, can be safely administered when carefully titrated. - Highlights: • We evaluate intravenous metoprolol usage in a mature cardiac CT imaging service. • Intravenous metoprolol is beneficial to achieve lower heart rates for CTCA. • IV metoprolol doses in excess of 15 mg is efficacious and safe with careful titration

  1. 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.

  2. Heart rate variability and plasma lipids in men with and without ischaemic heart disease

    DEFF Research Database (Denmark)

    Christensen, Jeppe Hagstrup; Toft, E; Christensen, Merete Stubkjær; Schmidt, Erik Berg

    1999-01-01

    Decreased 24-h heart rate variability (HRV) is associated with increased coronary mortality. The objective of this study was to examine the relation between plasma lipids and HRV (1) in men with a previous myocardial infarction (MI) and left ventricular dysfunction and (2) in healthy men. Forty seven men (mean age 63 years) with a previous MI and a left ventricular ejection fraction < or = 0.40 and 38 healthy men (mean age 37 years) were included. A 24-h Holter recording and fasting blood sample...

  3. fetal-ecg-readings-offer-no-advantage-over-heart-rate-monitoring-during-labor

    Science.gov (United States)

    ... Releases News Release Wednesday, August 12, 2015 Fetal ECG readings offer no advantage over heart rate monitoring ... National Institutes of Health. The technology provides electrocardiogram (ECG) readings of a fetus’s heart during the birth ...

  4. Heart rate monitoring and control in altered gravity conditions.

    Science.gov (United States)

    Di Rienzo, M; Parati, G; Rizzo, F; Meriggi, P; Merati, G; Faini, A; Castiglioni, P

    2007-01-01

    On the basis of indirect evidences it has been hypothesized that during space missions the almost complete absence of gravity might impair the baroreflex control of circulation. In the first part of this paper we report results obtained from a series of experiments carried out to directly verify this hypothesis during the 16-day STS 107 Shuttle flight. Spontaneous baroreflex sensitivity was assessed in four astronauts before flight (baseline) and at days 0-1, 6-7 and 12-13 during flight, both at rest and while performing moderate exercise. Our results indicate that at rest the baroreflex sensitivity significantly increased in the early flight phase, as compared to pre-flight values and tended to return to baseline in the mid-late phase of flight. During exercise, baroreflex sensitivity was lower than at rest, without any difference among pre-flight and in-flight values. These findings seem to exclude the hypothesis of an impairment of the baroreflex control of heart rate during exposure to microgravity, at least over a time window of 16 days. In the second part of the paper we propose a novel textile-based methodology for heart rate and other vital signs monitoring during gravity stress. The positive results obtained from its use during parachute jumps support the use of smart garments for the unobtrusive assessment of physiological parameters in extreme environments. PMID:18003559

  5. Importance of heart rate analysis in exercise tolerance test

    Scientific Electronic Library Online (English)

    Artur Haddad, Herdy; Carlos Eduardo Schio, Fay; Christian, Bornschein; Ricardo, Stein.

    2003-08-01

    Full Text Available After many years away from the limelights, at the beginning of this century, exercise tolerance testing has earned back an important position in international medical journals. The different sorts of information derived from a variety of studies based on it have shown us that this propedeutic method [...] has a highly valuable prognostic impact. Because of its low cost and easy applicability, the exercise testing reinforces its position in the clinical practice of the cardiologist. In the early 70's, research relating the influence of the autonomic nervous system in heart rate behavior in all phases of an exercise tolerance testing began. Ever since, a number of hypotheses tried to clarify which would be the mechanisms related to the chronotropic response during effort and its performance in the recovery period. In this updating article the authors deal with an important data referring to the chronotropic deficit and the abnormal heart rate recovery, commenting on the prognostic implication of keeping the focus on the potential of its clinical impact. In other words, approaches that can be used whenever there is someone performing a monitored exercise tolerance testing.

  6. Importance of heart rate analysis in exercise tolerance test

    Directory of Open Access Journals (Sweden)

    Herdy Artur Haddad

    2003-01-01

    Full Text Available After many years away from the limelights, at the beginning of this century, exercise tolerance testing has earned back an important position in international medical journals. The different sorts of information derived from a variety of studies based on it have shown us that this propedeutic method has a highly valuable prognostic impact. Because of its low cost and easy applicability, the exercise testing reinforces its position in the clinical practice of the cardiologist. In the early 70's, research relating the influence of the autonomic nervous system in heart rate behavior in all phases of an exercise tolerance testing began. Ever since, a number of hypotheses tried to clarify which would be the mechanisms related to the chronotropic response during effort and its performance in the recovery period. In this updating article the authors deal with an important data referring to the chronotropic deficit and the abnormal heart rate recovery, commenting on the prognostic implication of keeping the focus on the potential of its clinical impact. In other words, approaches that can be used whenever there is someone performing a monitored exercise tolerance testing.

  7. Control of heart rate during exercise in health and disease.

    Science.gov (United States)

    Gallo, L; Maciel, B C; Marin-Neto, J A; Martins, L E; Lima-Filho, E C; Golfetti, R; Chacon, M P; Forti, V A

    1995-01-01

    The authors present a review of their contributions over the last decade to the study of the autonomic control of heart rate during dynamic exercise under physiological and pathological conditions. These studies included the development of new methods for the evaluation of autonomic control of heart rate during dynamic exercise in man. Pharmacological blockade of sympathetic (propranolol) and parasympathetic (atropine) efferent nerves was used to demonstrate differences in time constants and power-dependent relative participation of each division of the autonomic nervous system, as predominant mechanisms responsible for the tachycardia occurring during dynamic exercise. These findings have permitted the use of properly standardized dynamic exercise (discontinuous protocol: step powers, seated position on a bicycle ergometer, 4-min duration), as a simple and noninvasive test for the evaluation of autonomic control of the sinus node. This test has proved to be useful for detecting physiological autonomic adaptations induced by aerobic training, as well as dysfunctions occurring in pathologic conditions such as Chagas' disease and hyperthyroidism. PMID:8728845

  8. Motion-compensated non-contact detection of heart rate

    Science.gov (United States)

    Yang, Lei; Liu, Ming; Dong, Liquan; Zhao, Yuejin; Liu, Xiaohua

    2015-12-01

    A new non-contact heart rate detection method based on the dual-wavelength technique is proposed and demonstrated experimentally. It is a well-known fact that the differences in the circuits of two detection modules result in different responses of two modules for motion artifacts. This poses a great challenge to compensate the motion artifacts during measurements. In order to circumvent this problem, we have proposed the amplitude spectrum and phase spectrum adaptive filter. Comparing with the time-domain adaptive filter and independent component analysis, the amplitude spectrum and phase spectrum adaptive filter can suppress the interference caused by the two circuit differences and effectively compensate the motion artifacts. To make the device is much compact and portable, a photoelectric probe is designed. The measurement distance is from several centimeters up to several meters. Moreover, the data obtained by using this non-contact detection system is compared with those of the conventional finger blood volume pulse (BVP) sensor by simultaneously measuring the heart rate of the subject. The data obtained from the proposed non-contact system are consistent and comparable with that of the BVP sensor.

  9. 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.

  10. 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

  11. 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).

  12. Ivabradine: a new rate-limiting therapy for coronary artery disease and heart failure

    OpenAIRE

    Rushworth, Gordon F; Lambrakis, Philippe; Stephen J. Leslie

    2011-01-01

    Ivabradine is a new bradycardic agent acting on the If channels of sinoatrial nodal cells to decrease the rate of diastolic depolarization and thus heart rate. The benefit of ivabradine over other negatively chronotropic agents is its absence of negative inotropy. Effective management of coronary artery disease, in terms of reducing morbidity and mortality, is reliant on controlling heart rate. Ivabradine has been shown to safely and effectively reduce heart rate without compromising cardiac ...

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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 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

  18. 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

    Energy Technology Data Exchange (ETDEWEB)

    Brodoefel, H. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany)], E-mail: h.brodoefel@t-online.de; Reimann, A. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Burgstahler, C. [Department of Cardiology, Eberhard-Karls-University, Otfried-Mueller-Str. 10, 72076 Tuebingen (Germany); Schumacher, F. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Herberts, T. [Department of Medical Biometry, Westbahnhofstr. 55, 72070 Tuebingen (Germany); Tsiflikas, I. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany); Schroeder, S. [Department of Cardiology, Eberhard-Karls-University, Otfried-Mueller-Str. 10, 72076 Tuebingen (Germany); Claussen, C.D.; Kopp, A.F.; Heuschmid, M. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tuebingen (Germany)

    2008-04-15

    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 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.

  19. EFFECT OF BRONCHODILATORS ON HEART RATE VARIABILITY IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE

    Directory of Open Access Journals (Sweden)

    H. H. Shugushev

    2015-12-01

    Full Text Available Aim. To study effect of long-acting theophylline (Theotard, KRKA and combination of salmeterol and fluticasone (Seretide, GlaxoSmithKline on heart rhythm variability (HRV and number of arrhythmic episodes in patients with chronic obstructive pulmonary disease (COPD.Material and methods. 144 patients with COPD and 35 patients of control group were examined. The analysis of HRV and Holter monitoring were made f on 2th and 14th days.Results. Treatment with both drugs led to increase in power of low- and high frequencies and their ratio (LF/HF, decrease in rate of supraventricular and ventricular arrhythmias. Theophylline therapy raised in a number of single and pair supraventricular extrasystoles. Treatment with combination of salmeterol and fluticasone did not change a number of extrasystoles.Conclusion. Combination of salmeterol and fluticasone is more preferable as a broncholytic therapy for patients with COPD and heart rhythm disorders.

  20. Blood pressure, heart rate and lipids in professional handball and water polo players

    Directory of Open Access Journals (Sweden)

    Jovanovi? Jovica

    2005-01-01

    Full Text Available Introduction: Blood pressure, heart rate and lipoprotein lipids are affected by family history, obesity, diet, smoking and physical activity habits. The aim of this paper was to estimate the values of blood pressure and heart rate in professional handball and water polo players before and after training and submaximal exercise test and to analyze the lipid state in these professional athletes in comparison with people who have never been in sports. Material and methods The investigation included 30 professional handball players, 30 professional water polo players and 15 men who have never been in sports (control group. All groups were matched for age, smoking habits, family predisposition to arterial hypertension and dyslipidemia. Results Between these groups there were statistically significant differences of blood pressure values and heart rate in the state of rest, after exercise test and after the training. There were also statistically significant differences of total cholesterol values, LDL cholesterol, triglycerides, HDL cholesterol, LDL cholesterol/HDL cholesterol ratio and total cholesterol/HDL ratio between these groups. Discussion Differences between these groups can be explained by various values of body mass index, by activity of lipoprotein lipase in athletes, by body position during the sports activity, by thermoregulatory vasoconstriction in the water, and by effects of hydrostatic pressure and reflex mechanisms during swimming. Conclusions Cardiovascular reaction in professional athletes depends on the type of sports activity, body position and medium during training. Professional athletes have a lower atherogenic risk than non-sportsmen. Changes of blood pressure and heart rate after submaximal exercise test are not the same as changes after training. .

  1. Central Autonomic Dysfunction Delays Recovery of Fingolimod Induced Heart Rate Slowing

    Science.gov (United States)

    Hilz, Max J.; Intravooth, Tassanai; Moeller, Sebastian; Wang, Ruihao; Lee, De-Hyung; Koehn, Julia; Linker, Ralf A.

    2015-01-01

    Background In multiple sclerosis (MS) patients, Fingolimod may induce prolonged heart-rate slowing which might be caused by MS-related central autonomic lesions. Objectives To evaluate whether MS-patients with prolonged heart-rate slowing (> six hours) upon Fingolimod show cardiovascular-autonomic dysfunction before Fingolimod-initiation. Methods Before Fingolimod-initiation, we recorded electrocardiographic RR-intervals (RRIs) and blood-pressure (BP) at rest, upon standing-up, during metronomic deep-breathing, Valsalva-maneuver, and “sustained-handgrip-exercise” in 21 patients with relapsing-remitting MS, and 20 healthy persons. We calculated sympathetic and parasympathetic cardiovascular parameters, including low- (LF) and high-frequency (HF) powers of RRI- and BP-oscillations, RRI-RMSSDs, RRI- and BP-changes during handgrip-exercise, parasympathetic heart-rate-slowing in relation to BP-overshoot after Valsalva-strain-release. We compared values of healthy persons and patients with and without prolonged heart-rate slowing after Fingolimod-initiation (ANOVA; significance: p<0.05). Results Upon Fingolimod-initiation, 7/21 patients had prolonged HR-slowing. Before Fingolimod, these patients had higher resting BP and higher BP increase during handgrip-exercise than had the other participants (p<0.05). They did not reduce parasympathetic HR-parameters upon standing-up. After Valsalva-strain-release, their parasympathetic HR-slowing in response to BP-overshoot was four times higher than in the other participants (p<0.05). Conclusions The autonomic cardiovascular dysfunction in MS-patients with delayed HR-re-acceleration upon Fingolimod-initiation suggests that MS-related central autonomic lesions compromise HR-re-acceleration upon Fingolimod. Trial Registration German Clinical Trial Register DRKS00004548 http://drks-neu.uniklinik-freiburg.de/drks_web/setLocale_EN.do PMID:26147106

  2. Heart Rate and Initial Presentation of Cardiovascular Diseases (Caliber)

    Science.gov (United States)

    2013-09-17

    Abdominal Aortic Aneurysm; Coronary Heart Disease NOS; Unheralded Coronary Death; Intracerebral Haemorrhage; Heart Failure; Ischemic Stroke; Myocardial Infarction; Stroke; Peripheral Arterial Disease; Stable Angina Pectoris; Subarachnoid Haemorrhage; Transient Ischemic Attack; Unstable Angina; Cardiac Arrest, Sudden Cardiac Death

  3. 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.

  4. The Use of Heart Rate Variability Technique for Differential Diagnostics of Peptic Ulcer and Idiopathic Duodenal Ulcers

    Directory of Open Access Journals (Sweden)

    D.?. Chizhikov

    2015-06-01

    Full Text Available The aim of the investigation was to study the peculiarities of autonomic regulation using spectral analysis of heart rate variability for differential diagnostics of peptic ulcer and idiopathic duodenal ulcer. Materials and Methods. A stress level was assessed by vagosympathetic balance rate. Low-high frequency ratio in a frequency spectrum of heart rate was used as a marker of vagosympathetic balance of stress. Endoscopic findings were compared with Helicobacter pylori test, and autonomic status was studied using spectral analysis of heart rate variability. Results. We found significant differences in low/high frequency ratio in the spectrum of heart rate of patients with Hp-positive and Hp-negative duodenal ulcers. The result proved stress nature of idiopathic ulcers. Idiopathic ulcers are characterized by significant increase of LF/HF that can serve as a differential diagnostic criterion for different types of duodenal ulcers. Conclusion. Spectral analysis of heart rate variability can be used in differential diagnostics of peptic ulcers and idiopathic ulcers.

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

    Science.gov (United States)

    Georgieva, A. E.; Payne, S. J.; Moulden, M.; Redman, C. W. G.

    2010-10-01

    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°) and `modified' Positive Predictive Value (PPV°) 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.

  6. 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.

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

    Directory of Open Access Journals (Sweden)

    G. Kheder

    2009-11-01

    Full Text Available 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. 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.

  9. Emergence of dynamical complexity related to human heart rate variability

    Science.gov (United States)

    Chang, Mei-Chu; Peng, C.-K.; Stanley, H. Eugene

    2014-12-01

    We apply the refined composite multiscale entropy (MSE) method to a one-dimensional directed small-world network composed of nodes whose states are binary and whose dynamics obey the majority rule. We find that the resulting fluctuating signal becomes dynamically complex. This dynamical complexity is caused (i) by the presence of both short-range connections and long-range shortcuts and (ii) by how well the system can adapt to the noisy environment. By tuning the adaptability of the environment and the long-range shortcuts we can increase or decrease the dynamical complexity, thereby modeling trends found in the MSE of a healthy human heart rate in different physiological states. When the shortcut and adaptability values increase, the complexity in the system dynamics becomes uncorrelated.

  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. Effect of Smoking on Blood Pressure and Resting Heart Rate : A Mendelian Randomisation Meta-Analysis in the CARTA Consortium

    DEFF Research Database (Denmark)

    Linneberg, Allan; Jacobsen, Rikke K

    2015-01-01

    BACKGROUND: -Smoking is an important cardiovascular disease risk factor, but the mechanisms linking smoking to blood pressure are poorly understood. METHODS AND RESULTS: -Data on 141,317 participants (62,666 never, 40,669 former, 37,982 current smokers) from 23 population-based studies were included in observational and Mendelian randomisation (MR) meta-analyses of the associations of smoking status and smoking heaviness with systolic and diastolic blood pressure (SBP, DBP), hypertension, and resting heart rate. For the MR analyses, a genetic variant rs16969968/rs1051730 was used as a proxy for smoking heaviness in current smokers. In observational analyses, current as compared with never smoking was associated with lower SBP, DBP, and lower hypertension risk, but with higher resting heart rate. In observational analyses amongst current smokers, one cigarette/day higher level of smoking heaviness was associated with higher (0.21 beats/minute; 95% CI 0.19; 0.24) resting heart rate, and slightly higher DBP (0.05 mmHg; 95% CI 0.02; 0.08) and SBP (0.08 mmHg; 95% CI 0.03; 0.13). However, in MR analyses amongst current smokers, while each smoking increasing allele of rs16969968/rs1051730 was associated with higher resting heart rate (0.36 beats/minute/allele; 95% CI 0.18; 0.54), there was no strong association with DBP, SBP, or hypertension. This would suggest a 7 beats/minute higher heart rate in those who smoke 20 cigarettes/day. CONCLUSIONS: -This MR meta-analysis supports a causal association of smoking heaviness with higher level of resting heart rate, but not with blood pressure. These findings suggest that part of the cardiovascular risk of smoking may operate through increasing resting heart rate.

  13. Early ventilation-heart rate breakpoint during incremental cycling exercise.

    Science.gov (United States)

    Gravier, G; Delliaux, S; Ba, A; Delpierre, S; Guieu, R; Jammes, Y

    2014-03-01

    Previous observations having reported a transient hypoxia at the onset of incremental exercise, we investigated the existence of concomitant ventilatory and heart rate (HR) breakpoints.33 subjects executed a maximal cycling exercise with averaging for successive 5-s periods of HR, ventilation, tidal volume (VT), mean inspiratory flow rate (VT/Ti), and end-tidal partial pressures of O2 (PETO2) and CO2. In 10 subjects, the transcutaneous partial pressure of O2 (PtcO2) was recorded and the venous blood lactic acid (LA) concentration measured.At the beginning of exercise, PETO2 decreased, reaching a nadir, then progressively increased until the exercise ended. PtcO2 varied in parallel. Whether or not a 0-W cycling period preceded the incremental exercise, the rate of changes in VE, VT, VT/Ti and HR significantly increased when the nadir PO2 was reached. The ventilatory/ HR breakpoint was measured at 33±4% of VO2max, whereas the ventilatory threshold (VTh) was detected at 67±4% of VO2max and LA began to increase at 45 to 50% of VO2max.During incremental cycling exercise, we identified the existence of HR and ventilatory breakpoints in advance of both lactate and ventilatory thresholds which coincided with modest hypoxia and hypercapnia. PMID:23945972

  14. 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...

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

    DEFF Research Database (Denmark)

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

    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 rep...

  16. 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 ...

  17. The heart rate after inhibition of nitric oxide release in the anaesthetized dog.

    OpenAIRE

    Pagliaro, Pasquale

    1996-01-01

    1. The effect of nitric oxide (NO) inhibition on heart rate was studied in anaesthetized vagotomized dogs. 2. The effect of changes of baroreceptor stimulation was prevented using an arterial pressure reservoir. 3. After NO-inhibitor (Nitro-L-arginine), heart rate decreased by 8% in spite of an unchanged pressure. 4. When upstream pressure was increased by constriction of the descending aorta, heart rate decreased by 4% before and after inhibition. Owing to the vagotomy this decrease was attr...

  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; Esko, Tõnu; Brundel, Bianca J J M; Peal, David S; Evans, David M; Nolte, Ilja M; Segrè, Ayellet V; Holm, Hilma; Handsaker, Robert E; Westra, Harm-Jan; Johnson, Toby; Isaacs, Aaron; Yang, Jian; Lundby, Alicia; Zhao, Jing Hua; Kim, Young Jin; Go, Min Jin; Almgren, Peter; Bochud, Murielle; Boucher, Gabrielle; Cornelis, Marilyn C; Gudbjartsson, Daniel; Hadley, David; van der Harst, Pim; Hayward, Caroline; den Heijer, Martin; Igl, Wilmar; Jackson, Anne U; Kutalik, Zoltán; Luan, Jian'an; Kemp, John P; Kristiansson, Kati; Ladenvall, Claes; Lorentzon, Mattias; Montasser, May E; Njajou, Omer T; O'Reilly, Paul F; Padmanabhan, Sandosh; St Pourcain, Beate; Rankinen, Tuomo; Salo, Perttu; Tanaka, Toshiko; Timpson, Nicholas J; Vitart, Veronique; Waite, Lindsay; Wheeler, William; Zhang, Weihua; Draisma, Harmen H M; Feitosa, Mary F; Kerr, Kathleen F; Lind, Penelope A; Mihailov, Evelin; Onland-Moret, N Charlotte; Song, Ci; Weedon, Michael N; Xie, Weijia; Yengo, Loic; Absher, Devin; Albert, Christine M; Alonso, Alvaro; Arking, Dan E; de Bakker, Paul I W; Balkau, Beverley; Barlassina, Cristina; Benaglio, Paola; Bis, Joshua C; Bouatia-Naji, Nabila; Brage, Søren; Chanock, Stephen J; Chines, Peter S; Chung, Mina; Darbar, Dawood; Dina, Christian; Dörr, Marcus; Elliott, Paul; Felix, Stephan B; Fischer, Krista; Fuchsberger, Christian; de Geus, Eco J C; Goyette, Philippe; Gudnason, Vilmundur; Harris, Tamara B; Hartikainen, Anna-Liisa; Havulinna, Aki S; Heckbert, Susan R; Hicks, Andrew A; Hofman, Albert; Holewijn, Suzanne; Hoogstra-Berends, Femke; Hottenga, Jouke-Jan; Jensen, Majken K; Johansson, Asa; Junttila, Juhani; Kääb, Stefan; Kanon, Bart; Ketkar, Shamika; Khaw, Kay-Tee; Knowles, Joshua W; Kooner, Angrad S; Kors, Jan A; Kumari, Meena; Milani, Lili; Laiho, Päivi; Lakatta, Edward G; Langenberg, Claudia; Leusink, Maarten; Liu, Yongmei; Luben, Robert N; Lunetta, Kathryn L; Lynch, Stacey N; Markus, Marcello R P; Marques-Vidal, Pedro; Leach, Irene Mateo; McArdle, Wendy L; McCarroll, Steven A; Medland, Sarah E; Miller, Kathryn A; Montgomery, Grant W; Morrison, Alanna C; M Vuml Ller-Nurasyid, Martina; Navarro, Pau; Nelis, Mari; O'Connell, Jeffrey R; O'Donnell, Christopher J; Ong, Ken K; Newman, Anne B; Peters, Annette; Polasek, Ozren; Pouta, Anneli; Pramstaller, Peter P; Psaty, Bruce M; Rao, Dabeeru C; Ring, Susan M; Rossin, Elizabeth J; Rudan, Diana; Sanna, Serena; Scott, Robert A; Sehmi, Jaban S; Sharp, Stephen; Shin, Jordan T; Singleton, Andrew B; Smith, Albert V; Soranzo, Nicole; Spector, Tim D; Stewart, Chip; Stringham, Heather M; Tarasov, Kirill V; Uitterlinden, André G; Vandenput, Liesbeth; Hwang, Shih-Jen; Whitfield, John B; Wijmenga, Cisca; Wild, Sarah H; Willemsen, Gonneke; Wilson, James Richard; Witteman, Jacqueline C M; Wong, Andrew; Wong, Quenna; Jamshidi, Yalda; Zitting, Paavo; Boer, Jolanda M A; Boomsma, Dorret I; Borecki, Ingrid B; van Duijn, Cornelia M; Ekelund, Ulf; Forouhi, Nita G; Froguel, Philippe; Hingorani, Aroon; Ingelsson, Erik; Kivimaki, Mika; Kronmal, Richard A; Kuh, Diana; Lind, Lars; Martin, Nicholas G; Oostra, Ben A; Pedersen, Nancy L; Quertermous, Thomas; Rotter, Jerome I; van der Schouw, Yvonne T; Verschuren, W M Monique; Walker, Mark; Albanes, Demetrius; Arnar, David O; Assimes, Themistocles L; Bandinelli, Stefania; Boehnke, Michael; de Boer, Rudolf A; Bouchard, Claude; Caulfield, W L Mark; Chambers, John C; Curhan, Gary; Cusi, Daniele; Eriksson, Johan; Ferrucci, Luigi; van Gilst, Wiek H; Glorioso, Nicola; de Graaf, Jacqueline; Groop, Leif; Gyllensten, Ulf; Hsueh, Wen-Chi; Hu, Frank B; Huikuri, Heikki V; Hunter, David J; Iribarren, Carlos; Isomaa, Bo; Jarvelin, Marjo-Riitta; Jula, Antti; Kähönen, Mika; Kiemeney, Lambertus A; van der Klauw, Melanie M; Kooner, Jaspal S; Kraft, Peter; Iacoviello, Licia; Lehtimäki, Terho; Lokki, Marja-Liisa L; Mitchell, Braxton D; Navis, Gerjan; Nieminen, Markku S; Ohlsson, Claes; Poulter, Neil R; Qi, Lu; Raitakari, Olli T; Rimm, Eric B; Rioux, John D; Rizzi, Federica; Rudan, Igor; Salomaa, Veikko; Sever, Peter S; Shields, Denis C; Shuldiner, Alan R; Sinisalo, Juha; Stanton, Alice V; Stolk, Ronald P; Strachan, David P; Tardif, Jean-Claude; Thorsteinsdottir, Unnur; Tuomilehto, Jaako; van Veldhuisen, Dirk J; Virtamo, Jarmo; Viikari, Jorma; Vollenweider, Peter; Waeber, Gérard; Widen, Elisabeth; Cho, Yoon Shin; Olsen, Jesper V; Visscher, Peter M; Willer, Cristen; Franke, Lude; Erdmann, Jeanette; Thompson, John R; Pfeufer, Arne; Sotoodehnia, Nona; Newton-Cheh, Christopher; Ellinor, Patrick T; Stricker, Bruno H Ch; Metspalu, Andres; Perola, Markus

    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 f...

  19. 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...

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

    OpenAIRE

    Valensi, Paul; Extramiana, Fabrice; Lange, Céline; 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 whi...

  1. Diurnal variations in arousal: a naturalistic heart rate study in children with ADHD

    OpenAIRE

    Imeraj, Lindita; Antrop, Inge; Roeyers, Herbert; Deschepper, Ellen; Bal, Sarah; Deboutte, Dirk

    2011-01-01

    Abstract Previous studies suggest an altered circadian regulation of arousal in children with attention-deficit hyperactivity disorder (ADHD) as measured by activity, circadian preference, and sleep-wake patterns. Although heart rate is an important measure to evaluate arousal profiles, to date it is unknown whether 24-h heart rate patterns differentiate between children with and without ADHD. In this study, 24-h heart rate data were collected in 30 non-medicated children with ADHD...

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

    OpenAIRE

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

    2014-01-01

    It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization.

  3. Parametric evaluation of heart rate variability during the menstrual cycle in young women.

    Science.gov (United States)

    Princi, Tanja; Parco, Sergio; Accardo, Agostino; Radillo, Oriano; De Seta, Francesco; Guaschino, Secondo

    2005-01-01

    Evaluation of heart rate variability (HRV) is based on analysis of consecutive R-R intervals and may provide quantitative information on the modulation of cardiac vagal and sympathetic efferent activities. In particular, power spectral analysis as well as the fractal dimension of HRV represent non-invasive measures that reflect brain-heart interaction in different physiopathological conditions. This study was performed to investigate the relationship between autonomic nervous cardiac influence and three phases (menses, follicular phase and luteal phase) of the menstrual cycle. Heart rate (HR) was recorded in 6 eumenorrheic young females, continuously for 20 min, at rest. From the tachograms, fractal dimension, FFT spectra and beta coefficient were evaluated. The components of two spectral bands were calculated: 0.040 Hz - 0.150 Hz (low frequency, LF), and 0.150 Hz - 0.80 Hz (high frequency, HF). The results indicate no correlation between HR and follicular as well as luteal phase of the menstrual cycle. Total power and HF spectral component increase, whereas LF spectral component decreases in the luteal phase compared to the follicular one. The fractal dimension does not show significant differences among the three phases. Beta coefficient decreases during luteal phase in respect of follicular one and menses. In conclusion, these results indicate in healthy young women a correlation between female sex hormones (17 beta-oestradiol, progesterone and pituitary gonadotrophins) concentrations and some HRV parameters with higher HR variability during the luteal phase. PMID:15850129

  4. 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.

  5. Relationship of 24-hour ambulatory blood pressure and heart rate with markers of hepatic function in cirrhotic patients

    Directory of Open Access Journals (Sweden)

    Stergiou George S

    2010-12-01

    Full Text Available Abstract Background There is evidence that in cirrhotic patients, certain hemodynamic parameters, such as blood pressure and heart rate, are related to the severity of liver disease. This study investigated whether non-invasive 24-hour ambulatory blood pressure and heart rate are more closely associated with markers of liver disease severity than conventional office measurements. Methods Ambulatory patients with cirrhosis underwent office blood pressure and heart rate measurements, 24-hour ambulatory blood pressure monitoring and blood laboratory tests. Results Fifty-one patients (32 men, mean age 57.4 ± 11.3 years completed the study. Twenty six patients had compensated liver cirrhosis (group A and 25 patients had more advanced liver disease (group B. Group A and B patients differed significantly both in ambulatory asleep diastolic blood pressure (p Conclusions Heart rate seems to be a more reliable marker of ongoing liver dysfunction than blood pressure. Evaluation of blood pressure and heart rate with 24-hour ambulatory measurement does not seem to offer more information than conventional office measurements.

  6. 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)

  7. 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...

  8. The compliance of the porcine pulmonary artery depends on pressure and heart rate.

    Science.gov (United States)

    Kornet, L; Jansen, J R; Nijenhuis, F C; Langewouters, G J; Versprille, A

    1998-11-01

    1. The influence of mean pulmonary arterial pressure (mean Ppa) on dynamic (Cd) and pseudo-static compliance (Cps) of the pulmonary artery was studied at a constant and a changing heart rate. Cd is the change in cross-sectional area (CSA) relative to the change in Ppa throughout a heart cycle. Cps is the change in mean CSA relative to the change in mean Ppa. If Cd is known, pulmonary blood flow can be computed from the Ppa using a windkessel model. We investigated whether Cps can be interchanged with Cd. 2. In nine anaesthetized pigs, we determined the mean CSA and Cd of the pulmonary artery at various Ppa levels, ranging from approximately 30 to 10 mmHg, established by bleeding. Two series of measurements were carried out, one series at a spontaneously changing heart rate (n = 9) and one series at a constant heart rate (n = 6). To determine CSA a conductance method was used. 3. Cps depended on pressure. The mean CSA versus mean Ppa curves were sigmoid and steepest in the series with the increasing heart rate (established by bleeding). The CSA versus Ppa loop during a heart cycle, giving Cd, was approximately linear and almost closed. The Cd versus mean Ppa relationship was bell shaped. Its width was smaller if the heart rate increased during the series of measurements. The pressure, where Cd was maximum, was higher at higher heart rates. Furthermore, the maximum Cd was not affected by the heart rate. 4. Because the pulmonary artery constricts with increasing heart rate, Cps will be overestimated during procedures where heart rate increases. Cd should be determined on a beat-to-beat basis to calculate flow because it changes with mean pulmonary arterial pressure and heart rate. PMID:9769432

  9. Leptin decreases heart rate associated with increased ventricular repolarization via its receptor.

    Science.gov (United States)

    Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H; Hull, Robert; Davis, Mary; Yu, Han-Gang

    2015-11-15

    Leptin has been proposed to modulate cardiac electrical properties via ?-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1-30 ?g/kg) decreased resting heart rate; at high doses (150-300 ?g/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03-0.3 ?g/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of ?-adrenergic receptor stimulation. During inhibition of ?-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias. PMID:26408544

  10. 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.

  11. Accuracy of Borg's ratings of perceived exertion in the prediction of heart rates during pregnancy.

    OpenAIRE

    O'Neill, M. E.; Cooper, K. A.; Mills, C. M.; Boyce, E S; Hunyor, S N

    1992-01-01

    When using Borg's 6-20 scale during pregnancy, ratings of perceived exertion (RPE) did not significantly correlate with exercise heart rates (HR) (P greater than 0.05). The HR predicted from RPE significantly (P less than 0.05) underestimated the exercise HR in the second trimester during walking (Group 1: mean difference 16 beats min-1, n = 11), aerobics classes (Group 4: mean 15 beats min-1, n = 48) and circuit training (Group 3: mean 18 beats min-1, n = 24); and in the third trimester duri...

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

    OpenAIRE

    Braulio Henrique Magnani Branco; Luis Miguel Massuça; Leonardo Vidal Andreato; Bianca Miarka; Luis Monteiro; Bruno Ferreira Marinho; Emerson Fanchini

    2013-01-01

    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 eac...

  13. Influence of heart rate on image quality of 64-slice spiral computed coronary angiography and optimization on reconstruction of phase window

    International Nuclear Information System (INIS)

    Objective: To evaluate the influence of heart rate on the image quality of 64-slice spiral computed coronary angiography (MSCTCA) and optimize the image reconstruction window. Methods: According to the heart rate, 86 patients were classified into 5 groups: group A, the heart rate ?60 beat per minute(BMP); group B,61-70BMP, group C,71-80BMP, and group D>80BMP. The image quality of MSCTCA was scored 5 grades from 1-5 according to heart motion artifact. The influences of heart rate and reconstruction phase on the image quality of MSCTCA were evaluated. Results: Average heart rate was 64.4 ±10.1BMP. Diagnostic image quality (score>3) was attained in 277 of 344 segments at the best reconstruction interval. There was a significant corxelation between average heart rate and image quality, but there was no difference between relative delay (%) reconstruction and absolute delay (ms) reconstruction on the image quality. Conclusion: Reducing average heart rate is beneficial for improving the image quality. (authors)

  14. [Analysis of the usefulness of different methods of the evaluation of heart rate during work in work load studies].

    Science.gov (United States)

    Makowiec-Dabrowska, T; Radwan-W?odarczyk, Z; Koszada-W?odarczyk, W

    1980-01-01

    The load of the circulatory system during work is usually evaluated basing on the heart beats above the heart rate at rest (i.e. the difference between the heart rate during work and at rest). To differentiate this evaluation according to the subjects' age, the percentage of heart rate reserve (the difference between the maximum heart rate and that at rest), constituted by the heart beats above the heart rate during work and at rest). To differentiate this evaluation according to the subjects' age, the percentage of heart rate reserve (the difference between the kers as well as at the model exercise on cycle ergometer in the group of students and female whitecollar workers has demonstrated that the heart rate before work is often higher than at breaks during the working day, whereas the heart rate during work depends on the output level when work results in a slight tachycardia. It was also found that incusion of the maximum heart rate results in much greater changes in evaluating individual groups--when it is calculated what percentage of this value constitutes heart rate at work, then when calculating the heart rate reserve percentage constituted by the difference between the maximum heart rate and that at rest. Therefore the calculation of the percentage of the maximum heart rate is promoted for evaluating the load of the circulatory system during work. PMID:7421570

  15. 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...

  16. Middle School Student's Heart Rates during Different Curricular Activities in Physical Education

    Science.gov (United States)

    Gao, Zan; Hannon, James C.; Carson, Russell L.

    2009-01-01

    The purpose of this study was to determine if students' heart rate outcomes in physical education varied as a function of activity and grade. A total of 146 sixth to eighth graders participated in different activities (i.e., walking/jogging, line dancing, soccer, and catch ball). Their average heart rate (AHR) and percentage of time in and above…

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

    DEFF Research Database (Denmark)

    Binici, Zeynep; Mouridsen, Mette Rauhe; Køber, Lars; Sajadieh, Ahmad

    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.

  18. 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

  19. 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…

  20. High 'Resting' Heart Rate Tied to Higher Odds of Early Death

    Science.gov (United States)

    High 'Resting' Heart Rate Tied to Higher Odds of Early Death But more research is needed before this can used as a ... risk of dying early, researchers suggest. "Higher resting heart rate is an independent predictor of all-cause and ...

  1. 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…

  2. Electroencephalogram and Heart Rate Regulation to Familiar and Unfamiliar People in Children with Autism Spectrum Disorders

    Science.gov (United States)

    Van Hecke, Amy Vaughan; Lebow, Jocelyn; Bal, Elgiz; Lamb, Damon; Harden, Emily; Kramer, Alexis; Denver, John; Bazhenova, Olga; Porges, Stephen W.

    2009-01-01

    Few studies have examined whether familiarity of partner affects social responses in children with autism. This study investigated heart rate regulation (respiratory sinus arrhythmia [RSA]: The myelinated vagus nerve's regulation of heart rate) and temporal-parietal electroencephalogram (EEG) activity while nineteen 8- to 12-year-old children with…

  3. 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

  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. Information and reward in voluntary heart rate control.

    Science.gov (United States)

    Bouchard, M A; Granger, L

    1980-10-01

    Two studies are reported which examined the relative effects of the pressence and absence of monetary incentives and instructions in a heart rate (HR) regulation task. Twelve male undergraduates were offered seven sessions of feedback assisted voluntary HR control training. In Experiment 1 six S s attempted to increase their HR with the aid of a "success," or positive binary visual signal. In Experiment 2 six S s were instructed to decrease their HR and were assisted by a "failure," or negative binary visual signal. In both studies the presence or absence of E's specific instructions to control HR was systematically varied from sessions 4 to 7. S s were paid on only half of the feedback trials of each session. These variables were thus systematically varied in a within-subject design. The main results suggest that (a) the instructions and monetary incentives significantly facilitated HR acceleration while showing no effects on HR deceleration; (b) in the no-instructions, no-incentive condition, HR control was minimal. The general hypothesis that Estes' interpretation of information and reward apply to human voluntary HR control received some support. It would appear that contrary to a traditional view, the exteroceptive feedback per se does not necessarily act as a reinforcer of the behavior, as witnessed for instance in the no-instructions, no-incentive conditions. PMID:7441224

  6. Heart-rate monitoring by air pressure and causal analysis

    Science.gov (United States)

    Tsuchiya, Naoki; Nakajima, Hiroshi; Hata, Yutaka

    2011-06-01

    Among lots of vital signals, heart-rate (HR) is an important index for diagnose human's health condition. For instance, HR provides an early stage of cardiac disease, autonomic nerve behavior, and so forth. However, currently, HR is measured only in medical checkups and clinical diagnosis during the rested state by using electrocardiograph (ECG). Thus, some serious cardiac events in daily life could be lost. Therefore, a continuous HR monitoring during 24 hours is desired. Considering the use in daily life, the monitoring should be noninvasive and low intrusive. Thus, in this paper, an HR monitoring in sleep by using air pressure sensors is proposed. The HR monitoring is realized by employing the causal analysis among air pressure and HR. The causality is described by employing fuzzy logic. According to the experiment on 7 males at age 22-25 (23 on average), the correlation coefficient against ECG is 0.73-0.97 (0.85 on average). In addition, the cause-effect structure for HR monitoring is arranged by employing causal decomposition, and the arranged causality is applied to HR monitoring in a setting posture. According to the additional experiment on 6 males, the correlation coefficient is 0.66-0.86 (0.76 on average). Therefore, the proposed method is suggested to have enough accuracy and robustness for some daily use cases.

  7. Heart rate variability and vagal tone in schizophrenia: A review.

    Science.gov (United States)

    Montaquila, Julian M; Trachik, Benjamin J; Bedwell, Jeffrey S

    2015-10-01

    Recent heart rate variability (HRV) research has identified diminished levels of parasympathetic activity among schizophrenia patients. Over two dozen empirically-based studies have been published on this topic; primarily over the last decade. However, no theoretical review appears to have been published on this work. Further, only one empirical study has evaluated HRV research findings in the context of documented hypothalamic-pituitary-adrenal axis hyperactivity in schizophrenia. HRV research indicates that no abnormalities exist in the initial sympathetic stress response of schizophrenia patients. However, evidence has consistently demonstrated that patients exhibit a diminished capacity to recover from a stress response as a result of deficits in parasympathetic activity. Moreover, this diminished parasympathetic nervous system (PNS) response, also known as decreased vagal tone, has been found to relate to increased symptom severity. Although these findings may cause speculation that the observed vagal tone disruption merely results from anxiety produced by the presence of positive symptomology, additional studies have identified similar parasympathetic dysfunction among nonpsychotic relatives of individuals with schizophrenia. We posit that the resulting sympathovagal imbalance leads to an overall sympathetic dominance despite the fact that sympathetic nervous system activity is not abnormally elevated among patients. Implications are discussed within the context of the diathesis-stress/vulnerability-stress model, including the potential for identifying a mechanism of action by which environmental stressors may contribute to triggering first-episode psychosis. PMID:26343595

  8. 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

  9. Heart rate and blood lactate during official female motorcycling competitions.

    Science.gov (United States)

    D'Artibale, E; Tessitore, A; Tiberi, M; Capranica, L

    2007-08-01

    The aim of this study was to investigate the physiological load of free practices (F), qualifying sessions (Q), and official races (R) of motorcycling competitions. Twenty-six female riders (age: 30.8 +/- 6.1 yrs) participated in this study. Anthropometric and strength evaluations were performed. Subject's heart rate (HR) was continuously recorded during three periods (5-minute Pre, Ride, and 5-minute Post) of the F, Q, and R phases of competitions. Blood lactate concentrations (La) were determined at rest and after riding. Riders had 56.5 +/- 6.7 kg of body mass, 164 +/- 4 cm of height, 21.6 +/- 4.4 % of body fat, and a BMI of 20.9 +/- 2.3 kg . (m (2)) (-1). Significant handgrip differences were found between the preferred (307 +/- 32 n) and non-preferred (281 +/- 47 N) limbs. During riding, frequency of occurrence of HR >or= 90 % HR (max) was 67 % in F, 74 % in Q, and 83 % in R. La after ridings (4.8 +/- 2.6 mmol . l (-1)) was two-folds (p motorcycling imposes a very intensive physical strain to the riders who need to control their motorbikes while performing frequent accelerations and decelerations. PMID:17455118

  10. 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.

  11. Heart rate variability interventions for concussion and rehabilitation.

    Science.gov (United States)

    Conder, Robert L; Conder, Alanna A

    2014-01-01

    The study of heart rate variability (HRV) has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain). It is well-established that lack of HRV implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal HRV 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 HRV 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. PMID:25165461

  12. From beat rate variability in induced pluripotent stem cell-derived pacemaker cells to heart rate variability in human subjects

    Science.gov (United States)

    Barad, Lili; Novak, Atara; Ben-Ari, Erez; Lorber, Avraham; Itskovitz-Eldor, Joseph; Rosen, Michael R; Weissman, Amir; Binah, Ofer

    2014-01-01

    Background We previously reported that induced Pluripotent Stem Cell-derived cardiomyocytes (iPSC-CM) manifest beat rate variability (BRV) resembling heart rate variability (HRV) in human sinoatrial node (SAN). We now hypothesized the BRV-HRV continuum originates in pacemaker cells. Objective To investigate whether cellular BRV is a source of HRV dynamics, we hypothesized three-levels of interaction among different cardiomyocyte entities: (1) single pacemaker cells, (2) networks of electrically coupled pacemaker cells and (3) in situ SAN. Methods We measured BRV/HRV properties in single pacemaker cells, iPSC-derived contracting embryoid bodies (EBs) and electrocardiograms from the same individual. Results Pronounced BRV/HRV were present at all three levels. Coefficient of variance (COV) of inter-beat intervals (IBI) and Poincaré plot SD1 and SD2 in single cells were 20x > EBs (P0.05). We also compared BRV magnitude among single cells, small (~5-10 cells) and larger EBs (>10 cells): BRV indices progressively increased (P<0.05) as cell number decreased. Disrupting intracellular Ca2+ handling markedly augmented BRV magnitude, revealing a unique bi-modal firing pattern, suggesting intracellular mechanisms contribute to BRV/HRV and the fractal behavior of heart rhythm. Conclusions The decreased BRV magnitude in transitioning from single cell to EB suggests HRV of hearts in situ originates from summation and integration of multiple cell-based oscillators. Hence, complex interactions among multiple pacemaker cells and intracellular Ca2+ handling determine HRV in humans and isolated cardiomyocyte networks. PMID:25052725

  13. 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

  14. 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 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

  15. 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.

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

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    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.

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

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    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.

  18. Association between Frequency Domain Heart Rate Variability and Unplanned Readmission to Hospital in Geriatric Patients

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    Fu Chin-Hua

    2011-02-01

    Full Text Available Abstract Background An accurate prediction of unplanned readmission (UR after discharge from hospital can facilitate physician's decision making processes for providing better quality of care in geriatric patients. The objective of this study was to explore the association of cardiac autonomic functions as measured by frequency domain heart rate variability (HRV and 14-day UR in geriatric patients. Methods Patients admitted to the geriatric ward of a regional hospital in Chiayi county in Taiwan were followed prospectively from July 2006 to June 2007. Those with invasive tubes and those who were heavy smokers, heavy alcohol drinkers, on medications that might influence HRV, or previously admitted to the hospital within 30 days were excluded. Cardiac autonomic functions were evaluated by frequency domain indices of HRV. Multiple logistic regression was used to assess the association between UR and HRV indices adjusted for age and length of hospitalization. Results A total of 78 patients met the inclusion criteria and 15 of them were readmitted within 14 days after discharge. The risk of UR was significantly higher in patients with lower levels of total power (OR = 1.39; 95% CI = 1.04-2.00, low frequency power (LF (OR = 1.22; 95% CI = 1.03-1.49, high frequency power (HF (OR = 1.27; 95% CI = 1.02-1.64, and lower ratios of low frequency power to high frequency power (LF/HF ratio (OR = 1.96; 95% CI = 1.07-3.84. Conclusion This is the first study to evaluate the association between frequency domain heart rate variability and the risk of UR in geriatric patients. Frequency domain heart rate variability indices measured on admission were significantly associated with increased risk of UR in geriatric patients. Additional studies are required to confirm the value and feasibility of using HRV indices on admission as a non-invasive tool to assist the prediction of UR in geriatric patients.

  19. Assessment of heart rate variability based on mobile device for planning physical activity

    Science.gov (United States)

    Svirin, I. S.; Epishina, E. V.; Voronin, V. V.; Semenishchev, E. A.; Solodova, E. N.; Nabilskaya, N. V.

    2015-05-01

    In this paper we present a method for the functional analysis of human heart based on electrocardiography (ECG) signals. The approach using the apparatus of analytical and differential geometry and correlation and regression analysis. ECG contains information on the current condition of the cardiovascular system as well as on the pathological changes in the heart. Mathematical processing of the heart rate variability allows to obtain a great set of mathematical and statistical characteristics. These characteristics of the heart rate are used when solving research problems to study physiological changes that determine functional changes of an individual. The proposed method implemented for up-to-date mobile Android and iOS based devices.

  20. Influence of Cardiovascular and Noncardiovascular Co-morbidities on Outcomes and Treatment Effect of Heart Rate Reduction With Ivabradine in Stable Heart Failure (from the SHIFT Trial).

    Science.gov (United States)

    Böhm, Michael; Robertson, Michele; Ford, Ian; Borer, Jeffrey S; Komajda, Michel; Kindermann, Ingrid; Maack, Christoph; Lainscak, Mitja; Swedberg, Karl; Tavazzi, Luigi

    2015-12-15

    Incidence of chronic heart failure (HF) increases with age and cardiovascular (CV) morbidity. Co-morbidities increase hospitalization and mortality in HF, and non-CV co-morbidities may lead to preventable hospitalizations. We studied the impact of co-morbidities on mortality and morbidity in Systolic Heart Failure Treatment with the If Inhibitor Ivabradine Trial, and investigated whether the impact of ivabradine was affected by co-morbidities. We analyzed the Systolic Heart Failure Treatment with the If Inhibitor Ivabradine Trialpopulation, with moderate-to-severe HF and left ventricular dysfunction (in sinus rhythm with heart rate at rest ?70 beats/min), according to co-morbidity: chronic obstructive pulmonary disease, diabetes mellitus, anemia, stroke, impaired renal function, myocardial infarction, hypertension, and peripheral artery disease. Co-morbidity load was classed as 0, 1, 2, 3, 4+ or 1 to 2 co-morbidities, or 3+ co-morbidities. Co-morbidities were evenly distributed between the placebo and ivabradine groups. Patients with more co-morbidities were likely to be older, women, had more advanced HF, were less likely to be on ? blockers, with an even distribution on ivabradine 2.5, 5, or 7.5 mg bid and placebo at all co-morbidity loads. Number of co-morbidities was related to outcomes. Cardiovascular death or HF hospitalization events significantly increased (p 3 co-morbidities for both, ivabradine and placebo. There was no interaction between co-morbidity load and the treatment effects of ivabradine. Hospitalization rate was lower at all co-morbidity loads for ivabradine. In conclusion, cardiac and noncardiac co-morbidities significantly affect CV outcomes, particularly if there are >3 co-morbidities. The effect of heart rate reduction with ivabradine is maintained at all co-morbidity loads. PMID:26508709

  1. 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.

  2. 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...

  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. Heart rate variability (HRV): an indicator of stress

    Science.gov (United States)

    Kaur, Balvinder; Durek, Joseph J.; O'Kane, Barbara L.; Tran, Nhien; Moses, Sophia; Luthra, Megha; Ikonomidou, Vasiliki N.

    2014-05-01

    Heart rate variability (HRV) can be an important indicator of several conditions that affect the autonomic nervous system, including traumatic brain injury, post-traumatic stress disorder and peripheral neuropathy [3], [4], [10] & [11]. Recent work has shown that some of the HRV features can potentially be used for distinguishing a subject's normal mental state from a stressed one [4], [13] & [14]. In all of these past works, although processing is done in both frequency and time domains, few classification algorithms have been explored for classifying normal from stressed RRintervals. In this paper we used 30 s intervals from the Electrocardiogram (ECG) time series collected during normal and stressed conditions, produced by means of a modified version of the Trier social stress test, to compute HRV-driven features and subsequently applied a set of classification algorithms to distinguish stressed from normal conditions. To classify RR-intervals, we explored classification algorithms that are commonly used for medical applications, namely 1) logistic regression (LR) [16] and 2) linear discriminant analysis (LDA) [6]. Classification performance for various levels of stress over the entire test was quantified using precision, accuracy, sensitivity and specificity measures. Results from both classifiers were then compared to find an optimal classifier and HRV features for stress detection. This work, performed under an IRB-approved protocol, not only provides a method for developing models and classifiers based on human data, but also provides a foundation for a stress indicator tool based on HRV. Further, these classification tools will not only benefit many civilian applications for detecting stress, but also security and military applications for screening such as: border patrol, stress detection for deception [3],[17], and wounded-warrior triage [12].

  5. Heart rate regulation and extreme bradycardia in diving emperor penguins.

    Science.gov (United States)

    Meir, Jessica U; Stockard, Torre K; Williams, Cassondra L; Ponganis, Katherine V; Ponganis, Paul J

    2008-04-01

    To investigate the diving heart rate (f(H)) response of the emperor penguin (Aptenodytes forsteri), the consummate avian diver, birds diving at an isolated dive hole in McMurdo Sound, Antarctica were outfitted with digital electrocardiogram recorders, two-axis accelerometers and time depth recorders (TDRs). In contrast to any other freely diving bird, a true bradycardia (f(H) significantly

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

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    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.

  7. 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

  8. Effects of melatonin and ethanol on the heart rate of Daphnia magna

    OpenAIRE

    Rebecca Kohn; Larissa Stuckey; Elizabeth Marion; Krithika Krishnarao; Bonnie Kaas

    2009-01-01

    Melatonin, an endogenous hormone that may regulate circadian rhythms by modulating cholinergic activity, is increasing in popular use as a natural treatment for sleep disorders. However, the effects of melatonin on the human heart are not well characterized, and the consequences of combining alcohol with melatonin are unknown. The myogenic heart of the water flea Daphnia magna (D. magna) is regulated by inhibitory cholinergic neurons that modulate cardiac function, including heart rate. D. ma...

  9. 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.

  10. Heart Rate Variability Correlates to Functional Aerobic Impairment in Hemodialysis Patients

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    Maria Angela Magalhães de Queiroz Carreira

    2015-06-01

    Full Text Available Background: Autonomic dysfunction (AD is highly prevalent in hemodialysis (HD patients and has been implicated in their increased risk of cardiovascular mortality. Objective: To correlate heart rate variability (HRV during exercise treadmill test (ETT with the values obtained when measuring functional aerobic impairment (FAI in HD patients and controls. Methods: Cross-sectional study involving HD patients and a control group. Clinical examination, blood sampling, transthoracic echocardiogram, 24-hour Holter, and ETT were performed. A symptom-limited ramp treadmill protocol with active recovery was employed. Heart rate variability was evaluated in time domain at exercise and recovery periods. Results: Forty-one HD patients and 41 controls concluded the study. HD patients had higher FAI and lower HRV than controls (p<0.001 for both. A correlation was found between exercise HRV (SDNN and FAI in both groups. This association was independent of age, sex, smoking, body mass index, diabetes, and clonidine or beta-blocker use, but not of hemoglobin levels. Conclusion: No association was found between FAI and HRV on 24-hour Holter or at the recovery period of ETT. Of note, exercise HRV was inversely correlated with FAI in HD patients and controls. (Arq Bras Cardiol. 2015; [online]. ahead print, PP.0-0

  11. Does Acupuncture Reduce Stress Over Time? A Clinical Heart Rate Variability Study in Hypertensive Patients.

    Science.gov (United States)

    Sparrow, Kristen; Golianu, Brenda

    2014-10-01

    Background: Heart rate variability (HRV), a noninvasive autonomic measure, has been applied to acupuncture interventions in controlled academic settings comparing points used, types of stimulation, or the HRV parameters measured. There is evidence that acupuncture decreases the stress response in both human and animal subjects, and can increase HRV in the short term (minutes to hours). Objectives: The goal of this study was to explore an array of HRV parameters during acupuncture sessions and over the course of treatment (weeks to months) in a series of patients being treated for hypertension. Materials and Methods: This was a retrospective, uncontrolled case study of patients presenting to a private acupuncture clinic. Patients received manual body acupuncture prescribed by the tenets of Traditional Chinese Medicine (TCM) and by published protocols for hypertension treatment. Heart rate was monitored during and after needle placement. The tracings were then analyzed with the Vivosense HRV analysis system. The main outcome measures were were patients' blood pressure measurements and low-frequency-to-high-frequency (LF/HF) ratio of HRV. Results: Patients tended to have an increase in their HRV during treatment, after needling, and, in some instances, an increase in HRV over weeks to months. Conclusions: Some patients' HRV increased over weeks to months during the course of acupuncture treatment for hypertension as evidenced by a decrease in their LF/HF ratio. This would indicate a relative decrease in their physiologic stress. PMID:25352944

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

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    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.

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

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    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.

  14. Effects of melatonin and ethanol on the heart rate of Daphnia magna

    Directory of Open Access Journals (Sweden)

    Rebecca Kohn

    2009-01-01

    Full Text Available Melatonin, an endogenous hormone that may regulate circadian rhythms by modulating cholinergic activity, is increasing in popular use as a natural treatment for sleep disorders. However, the effects of melatonin on the human heart are not well characterized, and the consequences of combining alcohol with melatonin are unknown. The myogenic heart of the water flea Daphnia magna (D. magna is regulated by inhibitory cholinergic neurons that modulate cardiac function, including heart rate. D. magna is a useful model organism for cardiovascular function, due to its physical transparency and susceptibility to cardioactive drugs known to affect the human heart. In this study, the effects of immersion in 10 mg/L melatonin and 5% ethanol on the heart rate of D. magna were quantified. Two-hour exposure to melatonin caused a significant decrease in heart rate, from 228 ± 2 bpm to 167 ± 8 bpm. Six-minute immersion in ethanol also significantly depressed the heart rate to 176 ± 10 bpm. Pretreatment with melatonin prior to the addition of ethanol resulted in a greater decrease in heart rate (89 ± 7 bpm than ethanol or melatonin alone. These findings indicate that melatonin and alcohol may combine to cause a greater depressive effect on cardiac function.

  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. 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

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

    International Nuclear Information System (INIS)

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

  18. 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.

  19. Heart Rate Analysis and Telemedicine: New Concepts & Maths

    Directory of Open Access Journals (Sweden)

    Sándor Khoór

    2008-01-01

    Full Text Available Our paper deals with some new aspects of ambulatory (Holter ECG monitoringextending its indications and using for risk management purpose. Remote sensing consistsof the transmittal of patient information, such as ECG, x-rays, or patient records, from aremote site to a collaborator in a distant site. Our earlier developed internet based ECGsystem was unique for on/off-line analysis of long-term ECG registrations. After the 5-yearexperience in a smaller region of Budapest, Hungary involving a municipal hospital andthe surrounding outpatient cardiology departments and general practitioners, we decidedto integrate into our new ECG equipment, the CardioClient the results. In the first clinicalstudy of the four was a wavelet, non-linear heart rate analysis in sudden cardiac deathpatients using the Internet and the GPRS mobile communication. After the wavelettransformation by the Haar wavelet and the Daubechies 10-tap wavelet, the phase-space ofthe wavelet-coefficient standard deviation and the scale parameters showed an excellentseparation in the scale-range of 3-6 between the two groups: in that region, the averagescaling exponents was 0.14+-0.04 for Group-A, and 1.22+-0.27 for Group-B (p<0.001. Inthe next study, we used the Internet database of long-term ambulatory, mobile, GPRSelectrocardiograms for the for risk stratification of patients through the cardiovascularcontinuum. From our ambulatory mobile GPRS ECG database the following a priorigroups were defined after a 24 months follow-up: G1: N=227 patients (without manifestcardiovascular disease, clusterized ‘boxes’ based on the age, sex, cholesterol level,diabetes, hypertension; G2: N=89 patients (postinfarction group; G3: N=66 (patientswith chronic heart failure with (+ or without (-: all-cause death (acD, myocardialinfarction (MI, malignant ventricular arrhythmia (MVA, sudden cardiac death (SCD.The actual vs. predicted values were analyzed with chi-square test. The best significancelevels (p<0.001 were found with method in G1/MI+, G2/SCD+, G3/acD+, G3/SCD+groups. In the third study a wavelet analysis of late potentials based on long-term, highresolution,mobile, GPRS ECG data was performed. These pathological changes were alsodetected by the Haar and Daubechies_4 wavelets, but in a narrower space (110-128 msand 180-240 and with lesser significance (p<0.01. Late potentials were found in Group-A(N=21 in 18 cases with Morlet, 16 with Haar, 19 with Daub-4 analysis, and in 15 casesusing all the 3 waves; for Group-B the data were 5, 9, 8, 5, respectively. In the fourthclinical study the prognostic value of the nonlinear dynamicity measurement of atrialfibrillation waves detected by GPRS internet long-term ECG monitoring were analyzed.The multivariate discriminant model selects the best parameters stepwise, the entry orremoval based on the minimalization of the Wilks’ lambda. Three variables remainedfinally: x1 = CI mean-value at log r=-1.0 (m9-14, x2 = CI mean-value at log r=-0.5 (m12-17, and x3 = CD_cg. The Wilks’ lambda was 0.011, chi-square 299.68, significancy:p<0,001.

  20. 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.

  1. Operative correction of judoists’ training loads on the base of on-line monitoring of heart beats rate

    Directory of Open Access Journals (Sweden)

    Liu Yong Qiang

    2015-02-01

    Full Text Available Purpose: ensure increase of effectiveness of training process’s control by means of operative correction of training loads of different qualification judo wrestlers’ heart beats rate indicators. Material: the research was conducted on the base of Brest SCJSOR ? 1. Judo wrestlers of different sport qualification (age 17-19 years old, n=15 participated in the research. Monitoring of judo wrestlers’ heart beats rate was carried out with the help of system “Polar”. Results: we have found factorial structure of functional fitness in every profile of sportsmen. Model characteristics of judo wrestlers were supplemented with the most important sides of functional fitness. Analysis of indicators of restoration effectiveness indicators (REI in both groups of judo wrestlers showed high level of organism’s responsiveness to training load of special and power orientation in comparison with speed power load. We have worked out algorithm of operative correction of training loads by indicators of heart beats rate in training process, depending on orientation and intensity of loads’ physiological influence on judo wrestler. Conclusions: Telemetric on-line monitoring of sportsman’s heart beats rate and calculation of REI permit to objectively assess effectiveness of training’s construction and of micro-cycle in total and detect in due time the trend to development of over-loading and failure of adaptation.

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

    Science.gov (United States)

    Chreiteh, Shadi S; Belhage, Bo; Hoppe, Karsten; Branebjerg, Jens; Thomsen, Erik V

    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. PMID:25570719

  3. 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.

  4. 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.

  5. 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

  6. Relationships between heart rate and PR interval during physiological and pharmacological interventions.

    OpenAIRE

    Carruthers, S. G.; McCall, B; Cordell, B A; Wu, R.

    1987-01-01

    The relationships between heart rates (HR) and corresponding PR intervals (PR) were studied in 12 healthy young subjects during rest, standing and graduated treadmill exercise to heart rates of 160 to 170 beats min-1 and during the infusion of isoprenaline to heart rates of 100 to 110 beats min-1. During exercise, PR diminished with increasing HR. Over the range of HR from 60 to 160 beats min-1 all 12 individual subjects exhibited negative linear correlations between HR and PR described by th...

  7. Adenosine-induced respiratory and heart rate changes in young and elderly adults.

    OpenAIRE

    Watt, A. H.; Bayer, A; P.A Routledge; Swift, C. G.

    1989-01-01

    The effects of intravenous boluses of adenosine on respiration and heart rate were compared in young and elderly individuals. Respiratory stimulation and biphasic changes in heart rate were confirmed. The dose-response relationship for the effects of adenosine on respiration and heart-rate did not differ significantly between 10 young (mean age 25.2 +/- 4.9 years) and 10 elderly (mean age 66 +/- 3.1 years) drug-free individuals, indicating that age is unlikely to be a major determinant of ade...

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

    OpenAIRE

    Dam, E. P.; D.R. Jonker; 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.

  9. 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.

  10. 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.

  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. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Stolzmann, Paul, E-mail: paul.stolzmann@usz.ch [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Goetti, Robert; Baumueller, Stephan [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Plass, Andre; Falk, Volkmar [Clinic for Cardiovascular Surgery, University Hospital Zurich (Switzerland); Scheffel, Hans; Feuchtner, Gudrun; Marincek, Borut [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Alkadhi, Hatem [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Leschka, Sebastian [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland)

    2011-07-15

    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 < 0.001) more often attributed to stair step artifacts in group 1. Segment-based sensitivity, specificity, PPV, NPV, and accuracy were 98%, 98%, 88%, 100%, and 100% among group 1; 96%, 99%, 90%, 100%, and 98% among group 2, respectively. Parameters of diagnostic performance were similar (all 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.

  14. 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.

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

    DEFF Research Database (Denmark)

    Malmqvist, L; Biering-Sørensen, T; Bartholdy, K; Krassioukov, A; Welling, K-L; Svendsen, J H; Kruse, A; Hansen, Birgitte; Biering-Sørensen, F

    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 SC...

  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. 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 lullaby m...

  18. Exploratory multivariate analysis of the effect of fatty fish consumption and medicinal use on heart rate and heart rate variability data

    OpenAIRE

    Grung, Bjørn; Hansen, Anita L; Berg, Mari; Møen-Knudseth, Maria P.; Olson, Gina; Thornton, David; Dahl, Lisbeth; Thayer, Julian F.

    2015-01-01

    The overall aim of the present study was to explore the relationship between medicinal use and fatty fish consumption on heart rate variability (HRV) and heart rate (HR) in a group of forensic inpatients on a variety of medications. A total of 49 forensic inpatients, randomly assigned to a fish group (n = 27) or a control group (n = 22) were included in the present study. Before and by the end of the food intervention period HR and HRV were measured during an experimental test procedure. An a...

  19. Estimation of organ-absorbed radiation doses during 64-detector CT coronary angiography using different acquisition techniques and heart rates: a phantom study

    International Nuclear Information System (INIS)

    Background: Though appropriate image acquisition parameters allow an effective dose below 1 mSv for CT coronary angiography (CTCA) performed with the latest dual-source CT scanners, a single-source 64-detector CT procedure results in a significant radiation dose due to its technical limitations. Therefore, estimating the radiation doses absorbed by an organ during 64-detector CTCA is important. Purpose: To estimate the radiation doses absorbed by organs located in the chest region during 64-detector CTCA using different acquisition techniques and heart rates. Material and Methods: Absorbed doses for breast, heart, lung, red bone marrow, thymus, and skin were evaluated using an anthropomorphic phantom and radiophotoluminescence glass dosimeters (RPLDs). Electrocardiogram (ECG)-gated helical and ECG-triggered non-helical acquisitions were performed by applying a simulated heart rate of 60 beats per minute (bpm) and ECG-gated helical acquisitions using ECG modulation (ECGM) of the tube current were performed by applying simulated heart rates of 40, 60, and 90 bpm after placing RPLDs on the anatomic location of each organ. The absorbed dose for each organ was calculated by multiplying the calibrated mean dose values of RPLDs with the mass energy coefficient ratio. Results: For all acquisitions, the highest absorbed dose was observed for the heart. When the helical and non-helical acquisitions were performed by applying a simulated heart rate of 60 bpm, the absorbed doses for heart were 215.5, 202.2, and 66.8 mGy for helical, helical with ECGM, and non-helical acquisitions, respectively. When the helical acquisitions using ECGM were performed by applying simulated heart rates of 40, 60, and 90 bpm, the absorbed doses for heart were 178.6, 139.1, and 159.3 mGy, respectively. Conclusion: ECG-triggered non-helical acquisition is recommended to reduce the radiation dose. Also, controlling the patients' heart rate appropriately during ECG-gated helical acquisition with ECGM is crucial

  20. Heart Rate Variability is a Predictor of Mortality in CKD - A Report from the CRIC Study

    Science.gov (United States)

    Drawz, Paul E; Babineau, Denise C; Brecklin, Carolyn; He, Jiang; Kallem, Radhakrishna R; Soliman, Elsayed Z; Xie, Dawei; Appleby, Dina; Anderson, Amanda H; Rahman, Mahboob

    2014-01-01

    Background/Aims Low heart rate variability (HRV) is a risk factor for adverse outcomes in the general population. We aimed to determine the factors associated with HRV and evaluate the association between low HRV and clinical outcomes in patients with chronic kidney disease (CKD). Methods A 10 second electrocardiogram was obtained at baseline in the Chronic Renal Insufficiency Cohort (CRIC) Study. HRV was measured by the standard deviation of all R-R intervals (SDNN) and the root mean square of successive differences between R-R intervals (RMSSD). Results In 3245 CRIC participants with available baseline SDNN and RMSSD, lower HRV was associated with older age, lack of exercise, heart failure, elevated phosphorus and hemoglobin A1c, and low estimated glomerular filtration rate. After a median follow-up of 4.2 years, in fully adjusted models, lower HRV was not associated with renal (SDNN: HR=0.96 (95% CI 0.88–1.05); RMSSD: HR=0.97 (95% CI 0.88–1.07)) or cardiovascular outcomes (SDNN: HR=1.02 (95% CI 0.92–1.13); RMSSD: HR=1.00 (95% CI 0.90–1.10)). There was a non-linear relationship between RMSSD and all-cause mortality with increased risk with both low and high RMSSD (P=0.04). Conclusions In a large cohort of participants with CKD, multiple risk factors for renal and cardiovascular disease were associated with lower HRV. Lower HRV was not associated with increased risk for renal or cardiovascular outcomes, but both low and high RMSSD were associated with increased risk for all-cause mortality. In conclusion, HRV as measured by RMSSD may be a novel and independent risk factor for mortality in CKD patients. PMID:24356377

  1. 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

  2. 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.

  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. 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

  5. PARTICULATE MATTER AND HEART RATE VARIABILITY AMONG ELDERLY RETIREES: THE BALTIMORE 1998 PM STUDY

    Science.gov (United States)

    This study investigates the reported relationship between ambient fine particle pollution and impaired cardiac autonomic control in the elderly. Heart rate variability (HRV) among 56 elderly (mean age 82) nonsmoking residents of a retirement center in Baltimore County, Maryland,...

  6. 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)

  7. Nonlinear Methods to Assess Changes in Heart Rate Variability in Type 2 Diabetic Patients

    Science.gov (United States)

    Bhaskar, Roy; Ghatak, Sobhendu

    2013-01-01

    Background Heart rate variability (HRV) is an important indicator of autonomic modulation of cardiovascular function. Diabetes can alter cardiac autonomic modulation by damaging afferent inputs, thereby increasing the risk of cardiovascular disease. We applied nonlinear analytical methods to identify parameters associated with HRV that are indicative of changes in autonomic modulation of heart function in diabetic patients. Objective We analyzed differences in HRV patterns between diabetic and age-matched healthy control subjects using nonlinear methods. Methods Lagged Poincaré plot, autocorrelation, and detrended fluctuation analysis were applied to analyze HRV in electrocardiography (ECG) recordings. Results Lagged Poincare plot analysis revealed significant changes in some parameters, suggestive of decreased parasympathetic modulation. The detrended fluctuation exponent derived from long-term fitting was higher than the short-term one in the diabetic population, which was also consistent with decreased parasympathetic input. The autocorrelation function of the deviation of inter-beat intervals exhibited a highly correlated pattern in the diabetic group compared with the control group. Conclusion The HRV pattern significantly differs between diabetic patients and healthy subjects. All three statistical methods employed in the study may prove useful to detect the onset and extent of autonomic neuropathy in diabetic patients. PMID:24008652

  8. 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.

  9. Stress level in wild harbour porpoises (Phocoena phocoena) during satellite tagging measured by respiration, heart rate and cortisol

    DEFF Research Database (Denmark)

    Eskesen, Ida Grønborg; Teilmann, J.; Geertsen, B. M.; Desportes, G.; Riget, F.; Dietz, R.; Larsen, Finn; Siebert, U.

    2009-01-01

    During satellite tagging of harbour porpoises (Phocoena phocoena), heart rate, respiration rate and cortisol value were measured to evaluate stress effects during handling and tagging. Respiration rates were obtained using video recordings, heart rates were recorded and serum cortisol levels were analysed from blood samples. Differences in heart rates, respiration rates and cortisol levels before and during the tagging events were investigated. An overall significant decrease Of 31.5% in respira...

  10. Clinical Applications of Heart Rate Variability in the Triage and Assessment of Traumatically Injured Patients

    OpenAIRE

    Kenneth G. Proctor; Thai Vu; Christian A. Otero; Chad M. Thorson; Ryan, Mark L

    2011-01-01

    Heart rate variability (HRV) is a method of physiologic assessment which uses fluctuations in the RR intervals to evaluate modulation of the heart rate by the autonomic nervous system (ANS). Decreased variability has been studied as a marker of increased pathology and a predictor of morbidity and mortality in multiple medical disciplines. HRV is potentially useful in trauma as a tool for prehospital triage, initial patient assessment, and continuous monitoring of critically injured patients. ...

  11. Heart rate variability and cardiac autonomic function in men with chronic alcohol dependence.

    OpenAIRE

    Malpas, S C; Whiteside, E A; Maling, T J

    1991-01-01

    Cardiac autonomic function was studied in 23 alcohol dependent men by standard tests of autonomic function and measurement of 24 hour heart rate variability. In all there was peripheral or central nervous system damage or both. Standard tests of autonomic function showed vagal neuropathy in seven. The remainder had normal autonomic function tests. Twenty four hour heart rate variability was measured as the standard deviation of the successive differences between RR intervals from an ambulator...

  12. 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...

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

    OpenAIRE

    Pegah ShojaMozafar; Sara Keshtkar; Ali Foroutan; Gholamhussian Erjaee; Alham Benabas

    2012-01-01

    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...

  14. Non-linear and scale-invariant analysis of the Heart Rate Variability

    CERN Document Server

    Kalda, J; Vainu, M; Laan, M

    2003-01-01

    Human heart rate fluctuates in a complex and non-stationary manner. Elaborating efficient and adequate tools for the analysis of such signals has been a great challenge for the researchers during last decades. Here, an overview of the main research results in this field is given. The following question are addressed: (a) what are the intrinsic features of the heart rate variability signal; (b) what are the most promising non-linear measures, bearing in mind clinical diagnostic and prognostic applications.

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

    DEFF Research Database (Denmark)

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

    1994-01-01

    INTRODUCTION: The term chaos is used to describe erratic or apparently random time-dependent behavior in deterministic systems. It has been suggested that the variability observed in the normal heart rate may be due to chaos, but this question has not been settled. METHODS AND RESULTS: Heart rate variability was assessed by recordings of consecutive RR intervals in ten healthy subjects using ambulatory ECG. All recordings were performed with the subjects at rest in the supine position. To test f...

  16. Fetal autonomic brain age scores, segmented heart rate variability analysis, and traditional short term variability

    OpenAIRE

    Hoyer, Dirk; Kowalski, Eva-Maria; Schmidt, Alexander; Tetschke, Florian; Nowack, Samuel; Rudolph, Anja; Wallwitz, Ulrike; Kynass, Isabelle; Bode, Franziska; Tegtmeyer, Janine; Kumm, Kathrin; Moraru, Liviu; Götz, Theresa; Haueisen, Jens; OTTO W. WITTE

    2014-01-01

    Disturbances of fetal autonomic brain development can be evaluated from fetal heart rate patterns (HRP) reflecting the activity of the autonomic nervous system. Although HRP analysis from cardiotocographic (CTG) recordings is established for fetal surveillance, temporal resolution is low. Fetal magnetocardiography (MCG), however, provides stable continuous recordings at a higher temporal resolution combined with a more precise heart rate variability (HRV) analysis. A direct comparison of CTG ...

  17. Effects of concentrated ambient particles on heart rate and blood pressure in pulmonary hypertensive rats.

    OpenAIRE

    Cheng, Tsun-Jen; Hwang, Jing-Shiang; Wang, Peng-Yau; Tsai, Chia-Fang; Chen, Chun-Yen; Lin, Sheng-Hsiang; Chan, Chang-Chuan

    2003-01-01

    Epidemiologic studies have shown that increased concentrations of ambient particles are associated with cardiovascular morbidity and mortality. However, the exact mechanisms remain unclear. Recent studies have revealed that particulate air pollution exposure is associated with indicators of autonomic function including heart rate, blood pressure, and heart rate variability. However, this association has not been clearly demonstrated in animal studies. To overcome the problems of wide variatio...

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

    DEFF Research Database (Denmark)

    Hansen, Tine Willum; Thijs, Lutgarde; Staessen, Jan A.; Boggia, José; Li, Yan; Wang, Jiguang; Kikuya, Masahiro; Ohkubo, Takayoshi; Imai, Yutaka; Björklund-Bodegård, Kristina; Lind, Lars; Richart, Tom; Sandoya, Edgardo; Jeppesen, Jørgen; Torp-Pedersen, Christian Tobias; Ibsen, Hans; O'Brien, Eoin

    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,...

  19. The Prognostic Value of Ambulatory Heart Rate Revisited in 6928 Subjects from 6 Populations

    DEFF Research Database (Denmark)

    Hansen, Tine Willum; Thijs, Lutgarde; Staessen, Jan A.; Boggia, José; Li, Yan; Wang, Jiguang; Kikuya, Masahiro; Ohkubo, Takayoshi; Imai, Yutaka; Björklund-Bodegård, Kristina; Lind, Lars; Richart, Tom; Staessen, Jan A; Sandoya, Edgardo; Jeppesen, Jørgen; Torp-Pedersen, Christian; Ibsen, Hans; O'Brien, Eoin

    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, 32...

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

    OpenAIRE

    GeoffreyGreen; ChristopheHerry; HeatherE.Wright

    2013-01-01

    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 (CIMVA™) software, heart rate (HR) ...

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

    OpenAIRE

    Stampfer HG; Dimmitt SB

    2013-01-01

    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 fo...

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

    DEFF Research Database (Denmark)

    Jensen, Magnus Thorsten; Marott, Jacob L; Lange, Peter; Vestbo, Jørgen; Schnohr, Peter; Nielsen, Olav Wendelboe; Skov Jensen, Jan; Jensen, Gorm B

    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...

  3. Resting Heart Rate is a Predictor of Mortality in Chronic Obstructive Pulmonary Disease

    DEFF Research Database (Denmark)

    Jensen, Magnus T; Marott, Jacob Louis; Lange, Peter; Vestbo, Jørgen; Schnohr, Peter; Nielsen, Olav Wendelboe; Jensen, Jan Skov; Jensen, Gorm Boje

    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 (p<0.001). RHR w...

  4. 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:...

  5. 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; Wölke, Gabriele; Lanki, Timo; Buzorius, Gintautas; Kreyling, Wolfgang G; de 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...

  6. Influence of alternate nostril breathing on heart rate variability in non-practitioners of yogic breathing

    Directory of Open Access Journals (Sweden)

    Shreya Ghiya

    2012-01-01

    Full Text Available Background: Long-term alternate nostril breathing (ANB has been shown to enhance autonomic control of the heart by increasing parasympathetic modulation. However, there is no information on the immediate effects of ANB on autonomic control compared to paced breathing (PB at the same rate in individuals who are inexperienced with yogic breathing. Aim: To examine cardiac autonomic modulation following ANB in comparison to that following PB in individuals who were inexperienced in ANB. Materials and Methods: Twenty healthy individuals (22.3 ± 2.9 years with no prior experience with ANB engaged in 30 min of both ANB and PB which were preceded and followed by 5 min of normal breathing (PRE, post-ANB, and post-PB, respectively. Mean arterial pressure (MAP and heart rate variability (HRV were assessed during all conditions. HRV was reported as spectral power in the total (lnTP, low-(lnLF, and high-frequency (lnHF ranges and were natural log (ln transformed. Results: Analysis of covariance revealed lnTP, lnLF and lnHF were greater during both post-ANB and post-PB compared to PRE (P<0.05. MAP and lnLF/lnHF did not significantly differ between conditions. Conclusions: These data suggest that there was an immediate increase in cardiac autonomic modulation following ANB and PB without a shift in autonomic balance in individuals inexperienced with yogic breathing. To our knowledge, this is the first investigation to investigate the autonomic effects of ANB in this population and also to compare the effects of ANB and PB at the same respiratory rate.

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

    DEFF Research Database (Denmark)

    Mitkidis, Panagiotis; McGraw, John J

    2015-01-01

    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.

  8. The Relationship between Ambient Air Pollution and Heart Rate Variability Differs for Individuals with Heart and Pulmonary Disease

    OpenAIRE

    Wheeler, Amanda; Zanobetti, Antonella; Gold, Diane R.; Schwartz, Joel David; Stone, Peter Howard; Suh MacIntosh, Helen H.

    2005-01-01

    Associations between concentrations of ambient fine particles [particulate matter < 2.5 ?m aerodynamic diameter (PM\\(_{2.5}\\))] and heart rate variability (HRV) have differed by study population. We examined the effects of ambient pollution on HRV for 18 individuals with chronic obstructive pulmonary disease (COPD) and 12 individuals with recent myocardial infarction (MI) living in Atlanta, Georgia. HRV, baseline pulmonary function, and medication data were collected for each participant on 7...

  9. 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...

  10. C-reactive protein, heart rate variability and prognosis in community subjects with no apparent heart disease

    DEFF Research Database (Denmark)

    Sajadieh, A; Nielsen, OW; Rasmussen, Verner; Hein, HO; Hansen, JF

    2006-01-01

    OBJECTIVES: Increased C-reactive protein (CRP) and reduced heart rate variability (HRV) both indicate poor prognosis. An inverse association between HRV and CRP has been reported, suggesting an interaction between inflammatory and autonomic systems. However, the prognostic impact of this interaction has not been studied. We thus investigated the prognostic impact of CRP, HRV and their combinations. DESIGN: Population-based study. SUBJECTS: A total of 638 middle-aged and elderly subjects with no ...

  11. Predicting survival in heart failure case and control subjects by use of fully automated methods for deriving nonlinear and conventional indices of heart rate dynamics

    Science.gov (United States)

    Ho, K. K.; Moody, G. B.; Peng, C. K.; Mietus, J. E.; Larson, M. G.; Levy, D.; Goldberger, A. L.

    1997-01-01

    BACKGROUND: Despite much recent interest in quantification of heart rate variability (HRV), the prognostic value of conventional measures of HRV and of newer indices based on nonlinear dynamics is not universally accepted. METHODS AND RESULTS: We have designed algorithms for analyzing ambulatory ECG recordings and measuring HRV without human intervention, using robust methods for obtaining time-domain measures (mean and SD of heart rate), frequency-domain measures (power in the bands of 0.001 to 0.01 Hz [VLF], 0.01 to 0.15 Hz [LF], and 0.15 to 0.5 Hz [HF] and total spectral power [TP] over all three of these bands), and measures based on nonlinear dynamics (approximate entropy [ApEn], a measure of complexity, and detrended fluctuation analysis [DFA], a measure of long-term correlations). The study population consisted of chronic congestive heart failure (CHF) case patients and sex- and age-matched control subjects in the Framingham Heart Study. After exclusion of technically inadequate studies and those with atrial fibrillation, we used these algorithms to study HRV in 2-hour ambulatory ECG recordings of 69 participants (mean age, 71.7+/-8.1 years). By use of separate Cox proportional-hazards models, the conventional measures SD (Pfollow-up period of 1.9 years; other measures, including ApEn (P>.3), were not. In multivariable models, DFA was of borderline predictive significance (P=.06) after adjustment for the diagnosis of CHF and SD. CONCLUSIONS: These results demonstrate that HRV analysis of ambulatory ECG recordings based on fully automated methods can have prognostic value in a population-based study and that nonlinear HRV indices may contribute prognostic value to complement traditional HRV measures.

  12. Predicting survival in heart failure case and control subjects by use of fully automated methods for deriving nonlinear and conventional indices of heart rate dynamics

    Science.gov (United States)

    Ho, K. K.; Moody, G. B.; Peng, C. K.; Mietus, J. E.; Larson, M. G.; Levy, D.; Goldberger, A. L.

    1997-01-01

    BACKGROUND: Despite much recent interest in quantification of heart rate variability (HRV), the prognostic value of conventional measures of HRV and of newer indices based on nonlinear dynamics is not universally accepted. METHODS AND RESULTS: We have designed algorithms for analyzing ambulatory ECG recordings and measuring HRV without human intervention, using robust methods for obtaining time-domain measures (mean and SD of heart rate), frequency-domain measures (power in the bands of 0.001 to 0.01 Hz [VLF], 0.01 to 0.15 Hz [LF], and 0.15 to 0.5 Hz [HF] and total spectral power [TP] over all three of these bands), and measures based on nonlinear dynamics (approximate entropy [ApEn], a measure of complexity, and detrended fluctuation analysis [DFA], a measure of long-term correlations). The study population consisted of chronic congestive heart failure (CHF) case patients and sex- and age-matched control subjects in the Framingham Heart Study. After exclusion of technically inadequate studies and those with atrial fibrillation, we used these algorithms to study HRV in 2-hour ambulatory ECG recordings of 69 participants (mean age, 71.7+/-8.1 years). By use of separate Cox proportional-hazards models, the conventional measures SD (P.3), were not. In multivariable models, DFA was of borderline predictive significance (P=.06) after adjustment for the diagnosis of CHF and SD. CONCLUSIONS: These results demonstrate that HRV analysis of ambulatory ECG recordings based on fully automated methods can have prognostic value in a population-based study and that nonlinear HRV indices may contribute prognostic value to complement traditional HRV measures.

  13. 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)

  14. Comparison of cardiac time intervals between echocardiography and impedance cardiography at various heart rates

    Directory of Open Access Journals (Sweden)

    Maureen A.J.M. van Eijnatten

    2014-04-01

    Full Text Available The non-invasively measured Initial Systolic Time Interval (ISTI reflects a time difference between the electrical and pumping activity of the heart and depends on cardiac preload, afterload, autonomic nervous control and training level. However, the duration of the ISTI has not yet been compared to other time markers of the heart cycle. The present study gauges the duration of the ISTI by comparing the end point of this interval, the C-point, with heart cycle markers obtained by echocardiography. The heart rate of 16 healthy subjects was varied by means of an exercise stimulus. It was found that the C-point, and therefore the end point of ISTI, occurred around the moment of the maximum diameter of the aortic arch in all subjects and at all heart rates. However, while the time difference between the opening of the aortic valves and the maximum diameter of the aortic arch decreased significantly with decreasing RR-interval, the time difference with respect to the moment of the C-point remained constant within the subjects. This means that the shortening of the ISTI with increasing heart rate in response to an exercise stimulus was caused by a shortening of the pre-ejection period (PEP. It is concluded that the ISTI can be used as a non-invasive parameter indicating the time difference between the electrical and mechanical pumping activity of the heart, both inside and outside the clinic.

  15. Long-term prognostic importance of resting heart rate in patients with left ventricular dysfunction in connection with either heart failure or myocardial infarction: the DIAMOND study

    DEFF Research Database (Denmark)

    Moller, Daniel Vega; Fosbøl, Emil Loldrup; Seibaek, Marie; Brendorp, Bente; Møller, Daniel Vega; Thune, Jens Jakob; Gislason, Gunnar H; Torp-Pedersen, Christian; Køber, Lars

    2010-01-01

    BACKGROUND: Elevated resting heart rate is associated with increased mortality in a variety of cardiac diseases, but comparisons between different clinical settings are lacking. We investigated the long-term prognostic importance of resting heart rate in patients hospitalized with left ventricular dysfunction in connection with either heart failure (HF) or myocardial infarction (MI). METHODS: In the Danish Investigations and Arrhythmia ON Dofetilide (DIAMOND) study; patients with left ventricula...

  16. Analysis of Heart Rate and Self-Injury with and without Restraint in an Individual with Autism

    Science.gov (United States)

    Jennett, Heather; Hagopian, Louis P.; Beaulieu, Lauren

    2011-01-01

    The relation between self-injury and heart rate was analyzed for an individual who appeared anxious while engaging in self-injury. The analysis involved manipulating the presence or absence of restraint while simultaneously measuring heart rate. The following findings were obtained and replicated: (a) when some form of restraint was applied, heart

  17. Initial experience of evaluation of coronary artery with 320-slice row CT system in high pre-test probability population without heart rate (rhythm) control

    International Nuclear Information System (INIS)

    Objective: To investigate the accuracy of 320-slice row CT system for the detection of coronary artery disease (CAD) in high pre-test probability population without heart rate/rhythm control. Methods: Thirty patients with a high pre-test probability of CAD underwent 320-slice row CT without preceding heart rate/rhythm control. Invasive coronary angiography (ICA) served as the standard reference. Data sets were evaluated by 2 observers in consensus with respect to stenoses ?50% decreased diameter. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and Youden index were analyzed; the impact of heart rate and calcification on image quality as well as diagnostic accuracy were also analyzed by Chi-square test. Results: Mean heart rate during scanning was 73.7±15.4 beats per min(bpm), and median(QR) of Agatston score of segment was 45.6 (181). On a per-segment analysis, overall sensitivity was 96.1% (74/77, 95% CI:89.03%-99.19%), specificity was 98.3% (337/343, 95% CI:96.23%-99.36%), PPV was 92.5% (74/80, 95% CI:84.39%-97.20%), NPV of 99.1% (337/340, 95% CI: 97.44%-99.82%) and the Youden index was 0.94. In both heart-rate subgroups (242 in heart rate < 70 bpm group, 169 in heart rate ?70 bpm group), diagnostic accuracy for the assessment of coronary artery stenosis was similar (P<0.05). The accuracy and the quality score of the subgroup Agatston score ?100 were lower than that of the subgroup Agatston score <100; however, the difference of results between 320-slice row CT and ICA was not significant (P<0.05). Conclusion: 320-detector row CT can reliably detect coronary artery stenoses in a high pre-test probability population without heart rate/rhythm control. (authors)

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

    OpenAIRE

    Jeon Moongu; Lee Sangwook; Park Jinho

    2009-01-01

    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 interval...

  19. 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.

  20. 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/m(2) 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 = 0.003) and SDNNindex increased by 11.4% (p = 0.0003). MeanNN increased by 2.4%, reflecting a decrease in mean heart rate from 74.1 to 72.3 beats/min (p = 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 = 0.002). Improvements in SDNN and cholesterol were correlated with weight loss (r = -0.329, p = 0.024 and r = 0.327, p = 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.

  1. Heart Rate-Based Prediction of Fixed Blood Lactate Thresholds in Professional Team-Sport Players.

    Science.gov (United States)

    Garcia-Tabar, Ibai; Llodio, Iñaki; Sánchez-Medina, Luis; Ruesta, Maite; Ibañez, Javier; Gorostiaga, Esteban M

    2015-10-01

    Garcia-Tabar, I, Llodio, I, Sánchez-Medina, L, Ruesta, M, Ibañez, J, and Gorostiaga, EM. Heart rate-based prediction of fixed blood lactate thresholds in professional team-sport players. J Strength Cond Res 29(10): 2794-2801, 2015-The aim of this study was to investigate whether the speed associated with 90% of maximal heart rate (S90%HRmax) could predict speeds at fixed blood lactate concentrations of 3 mmol·L (S3mM) and 4 mmol·L (S4mM). Professional team-sport players of futsal (n = 10), handball (n = 16), and basketball (n = 10) performed a 4-stage discontinuous progressive running test followed, if exhaustion was not previously achieved, by an additional maximal continuous incremental running test to attain maximal heart rate (HRmax). The individual S3mM, S4mM, and S90%HRmax were determined by linear interpolation. S3mM (11.6 ± 1.5 km·h) and S4mM (12.5 ± 1.4 km·h) did not differ (p > 0.05) from S90%HRmax (12.0 ± 1.2 km·h). Very large significant (p < 0.001) relationships were found between S90%HRmax and S3mM (r = 0.82; standard error of the estimates [SEE] = 0.87 km·h), as well as between S90%HRmax and S4mM (r = 0.82; SEE = 0.87 km·h). S3mM and S4mM inversely correlated with %HRmax associated with running speeds of 10 and 12 km·h (r = 0.78-0.81; p < 0.001; SEE = 0.94-0.87 km·h). In conclusion, S3mM and S4mM can be accurately predicted by S90%HRmax in professional team-sport players. PMID:25844867

  2. 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.

  3. 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.

  4. Forestry work in the Italians alps: metabolic demand assessed by heart rate

    Directory of Open Access Journals (Sweden)

    Angelo Rodio

    2007-06-01

    Full Text Available

    Objective: This research aims to: a assess the energy expenditure during typical forestry activities; b assess the actual workload of forestry work; c define the eventual relationship between oxygen uptake ( and heart rate during the studied working phases.

    Methods: Eleven healthy skilled forestry workers were studied. Using a portable device, oxygen uptake ( , carbon dioxide output ( , pulmonary ventilation ( and heart rate (HR were measured. The forestry work was divided into four phases: walking uphill, felling, limbing & chain-sawing and complementary activities. A work time report was kept and in each phase a weighted average (WA of all parameters was obtained.

    Results:Walking uphill, felling, limbing & chain-sawing activities did not show significant statistical differences between each other and were classified as heavy activities (mean 2.17 lmin-1,mean HR 157 beatmin-1. The complementary activity was found to be less demanding and statistically differed in respect to the others ( 0.55 l min-1, HR 98 beat min-1. By theWA, the actual workload of forestry work resulted in a moderate to heavyoptimal job ( and HR being 1.51 l min-1 and 133.5 beat min-1 respectively in a typical working day. Furthermore it was possible to set up a relationship between and HR for the forestry work.

    Conclusions: Forestry activity can be classified as moderate to heavy-optimal. Finally, a good and linear correlation between and HR proved to be an easy tool to evaluate the metabolic demand.

  5. Autonomic nervous activities assessed by heart rate variability in pre- and post-adolescent Japanese.

    Science.gov (United States)

    Fukuba, Yoshiyuki; Sato, Hironori; Sakiyama, Tomomi; Yamaoka Endo, Masako; Yamada, Masako; Ueoka, Hatsumi; Miura, Akira; Koga, Shunsaku

    2009-11-01

    There are many studies with respect to the age-related change of the characteristics of beat-to-beat heart rate variability (HRV), reflected by cardiac autonomic control, especially focusing on adulthood (i.e., aging related to the incidence of metabolic syndrome) in Japanese individuals. However, it is not still clear how basic control matures during childhood. This study was, therefore, designed to explore the HRV characteristics of pre- and post-adolescent Japanese, in a cross-sectional manner. Resting HRV data was recorded in a relaxing supine position from 136 healthy individuals between 8 and 20 years (48 boys between 8 and 14 years; 88 girls between 8 and 20 years) who were instructed to breathe periodically (0.25 Hz). Frequency-domain analysis (i.e., the spectral analysis based on an autoregressive model) of short-term, stationary R-R intervals was performed to evaluate the low- (LF; below 0.15 Hz) and high- (HF; 0.15-0.40 Hz) frequency powers. The HF to total power represents the vagal control of heart rate (PNS indicator), and the ratio of LF to HF (LF/HF) is considered to relate to the sympathetic modulations (SNS indicator). Both PNS and SNS indices had substantially no effect from age and/or gender in the range between 8 and 20 years. In conclusion, the control of the cardiac autonomic nervous system in Japanese seems already to be compatible with that in adulthood before approximately 10 years. In other word, the cardiac autonomic modulation would presumably be maturated before the age of approximately 7-8 years, though further research is awaited. PMID:20009374

  6. The assessment of cardiac sempathovagal activity by heart rate variability in patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    A. Jale Saraç

    2010-12-01

    Full Text Available Objectives: It has been reported that increased sempathic nerve system activity due to infalammatory stress and it cause disturbance of heart rate variability (HRV in rheumatoid arthritis (RA. In this study, it was assessed cardiac sempatovagal activity by noninvasive parameters such as HRV in patients with RA.Materials and methods: 49 patients with RA and age-matched 28 healthy subjects as control group were enrolled to this study. Clinical and laboratory parameters of all subjects were assessed and 24-hour electrocardiographic Holter monitoring were performed to all of them.Results: Minimum, maximum and mean heart rate were significantly higher while mean RR interval were significantly lower in patients with RA when compared with controls. In addition, among time domain HRV parameters, SDNN, SDANN ve triangular index were significantly lower in patients with RA (p<0.05, p<0.01, p<0.01, respectively. In correlation analysis, it was not found a significant association between HRV parameters and age, sex, duration and activity of disease, inflammatory markers, supraventricular or ventricular extrasystole (VES. There were only significant negative associations between VES and pNN50, SDANN and RMSDD. But, there was no independent correlation between these parameters.Conclusion: Non-invasive parameters such as HRV may have a modest role in assessment of cardiovascular risk and prediction of sudden cardiac death risk, in addition to the traditional risk factors, in patients with RA. However, to reach to the more accurate decision, there are need to carry out larger and long term studies which include different patients groups

  7. ‘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.

  8. Characteristics of sleep parameters and nocturnal heart rate dynamics in patients with psoriasis vulgaris

    Directory of Open Access Journals (Sweden)

    Rang-song HUI

    2011-11-01

    Full Text Available Objective To investigate the physiological features of patients with psoriasis vulgaris during sleep.Methods Thirty-six psoriasis patients were classified into the group with "blood-heat" syndrome(n=21 and the group with "blood-dry" syndrome(n=15.Fifteen healthy volunteers served as control.All the subjects underwent a nocturnal sleep examination using the micro-movement sensitive mattress sleep monitoring system(MSMSMS.The sleep indices and nocturnal heart rate dynamics of the patients were compared with that of the control,and also between the two groups with different syndrome.Results In comparison with the control group,both psoriasis patient groups showed the phenomena of poor sleep quality,such as the shallow sleep phase,disorder of sleep rhythm and increased slight-arousals.The slight-arousal occurred more often in blood-heat syndrome group than in blood-dry syndrome group,while the sleep latency was elongated more evidently in blood-dry syndrome group.Compared with the control group,the two patient groups presented a little decrease in heart rate(HR after sleeping.However,the HR increased in the first phase of sleep,and the variation coefficient of HR increased in the whole sleep period.An increase in HR variation coefficient was more obvious in blood-heat syndrome group than in blood-dry syndrome group(P < 0.05.Conclusions The phenomena of decreased sleep quality and the variation of nocturnal HR in psoriasis patients may be due to the failure of Yin to control Yang,and disturbance of heat to the mind induced by blood-heat and Yin deficiency.The degrees of the phenomena are different between the two psoriasis groups.There is also a decrease in parasympathetic activity and relative increase in sympathetic activity in both psoriasis groups,with manifestation of different features in patients with different syndromes.

  9. Evaluation of a technique to measure heart rate variability in anaesthetised cats.

    Science.gov (United States)

    Khor, Kuan Hua; Shiels, Ian A; Campbell, Fiona E; Greer, Ristan M; Rose, Annie; Mills, Paul C

    2014-02-01

    Analysis of heart rate (HR) and heart rate variability (HRV) are powerful tools to investigate cardiac diseases, but current methods, including 24-h Holter monitoring, can be cumbersome and may be compromised by movement artefact. A commercially available data capture and analysis system was used in anaesthetised healthy cats to measure HR and HRV during pharmacological manipulation of HR. Seven healthy cats were subjected to a randomised crossover study design with a 7 day washout period between two treatment groups, placebo and atenolol (1mg/kg, IV), with the efficacy of atenolol to inhibit ?1 adrenoreceptors challenged by epinephrine. Statistical significance for the epinephrine challenge was set at P<0.0027 (Holm-Bonferroni correction), whereas a level of significance of P<0.05 was set for other variables. Analysis of the continuous electrocardiography (ECG) recordings showed that epinephrine challenge increased HR in the placebo group (P=0.0003) but not in the atenolol group. The change in HR was greater in the placebo group than in the atenolol group (P=0.0004). Therefore, compared to cats pre-treated with placebo, pre-treatment with atenolol significantly antagonised the tachycardia while not significantly affecting HRV. The increased HR in the placebo group following epinephrine challenge was consistent with a shift of the sympathovagal balance towards a predominantly sympathetic tone. However, the small (but not significant at the critical value) decrease in the normalised high-frequency component (HFnorm) in both groups of cats suggested that epinephrine induced a parasympathetic withdrawal in addition to sympathetic enhancement (increased normalised low frequency component or LFnorm). In conclusion, this model is a highly sensitive and repeatable model to investigate HRV in anaesthetised cats that would be useful in the laboratory setting for short-term investigation of cardiovascular disease and subtle responses to pharmacological agents in this species. PMID:24321367

  10. 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 the chemotherapy. Thus it was suggested that the death by arrhythmia and the irreversible myocardial injury might be predictable. (author)

  11. In utero measurement of heart rate in mouse by noninvasive M-mode echocardiography.

    Science.gov (United States)

    Kim, Woojin; Seidah, Nabil G; Prat, Annik

    2013-01-01

    Congenital heart disease (CHD) is the most frequent noninfectious cause of death at birth. The incidence of CHD ranges from 4 to 50/1,000 births (Disease and injury regional estimates, World Health Organization, 2004). Surgeries that often compromise the quality of life are required to correct heart defects, reminding us of the importance of finding the causes of CHD. Mutant mouse models and live imaging technology have become essential tools to study the etiology of this disease. Although advanced methods allow live imaging of abnormal hearts in embryos, the physiological and hemodynamic states of the latter are often compromised due to surgical and/or lengthy procedures. Noninvasive ultrasound imaging, however, can be used without surgically exposing the embryos, thereby maintaining their physiology. Herein, we use simple M-mode ultrasound to assess heart rates of embryos at E18.5 in utero. The detection of abnormal heart rates is indeed a good indicator of dysfunction of the heart and thus constitutes a first step in the identification of developmental defects that may lead to heart failure. PMID:24300115

  12. What does the correlation dimension of the human heart rate measure?

    CERN Document Server

    Sakki, M; Vainu, M; Laan, M

    2001-01-01

    It is shown that for the heart rate variability, finite values of the correlation dimension D (calculated by the Grassberger-Procaccia algorithm) cannot be considered as an evidence for a deterministic chaos inside the heart. Finiteness of D is explained by finite resolving power of the recording apparatus. The correlation dimension depends both on the short-time variability of the heart rhythm, and on the resolving power of the electrocardiogram. In principle, it can be used as a certain measure of short-time variability of the signal, but its diagnostic value on test groups was negligible.

  13. AMBIENT POLLUTION AND HEART RATE VARIABILITY. (R826780)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. 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…

  15. Low-Level Lead Exposure, Metabolic Syndrome, and Heart Rate Variability: The VA Normative Aging Study

    OpenAIRE

    Nie, Huiling; Hu, Howard; Park, Sung Kyun; Schwartz, Joel David; Weisskopf, Marc G; Sparrow, David; Vokonas, Pantel S.; Wright, Robert O; Coull, Brent Andrew

    2006-01-01

    Background: Altered heart rate variability (HRV), a marker of poor cardiac autonomic function, has been associated with sudden cardiac death and heart failure. Objective: We examined the association of low-level lead exposure measured in bone by K-X-ray fluorescence with alterations in HRV, and whether metabolic syndrome (MetS) or its individual components modify those associations. Methods: HRV measures [power in high-frequency (HF\\(_{norm}\\)) and low-frequency (LF\\(_{norm}\\)) in normalized ...

  16. Frequency dependent effect of selective biphasic left vagus nerve stimulation on heart rate and arterial pressure

    OpenAIRE

    MATEJ PODBREGAR; IVAN RADAN; TOMISLAV MIRKOVIC; IVAN KNEŽEVI?; BORUT GERŠAK; JANEZ ROZMAN

    2012-01-01

    Activation of the parasympathetic pathway leads to negative chronotropic, dromotropic, and inotropic changes of heart function. The ability to selectively stimulate certain superficial compartments of peripheral nerves has been demonstrated previously. The aim of the present study was to find a clinically acceptable selective biphasic vagus nerve stimulation technique, which could allow gradual regulation of heart rate and systemic arterial pressure. In two patients, the left vagus nerve was...

  17. 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 ...

  18. The compliance of the porcine pulmonary artery depends on pressure and heart rate

    OpenAIRE

    Kornet, L.; Jansen, J.R.C.; Nijenhuis, F.C.A.M. te; Langewouters, G.J.; Versprille, A

    1998-01-01

    1. The influence of mean pulmonary arterial pressure (mean Ppa) on dynamic (Cd) and pseudo-static compliance (Cps) of the pulmonary artery was studied at a constant and a changing heart rate. Cd is the change in cross-sectional area (CSA) relative to the change in Ppa throughout a heart cycle. Cps is the change in mean CSA relative to the change in mean Ppa. If Cd is known, pulmonary blood flow can be computed from the Ppa ...

  19. Effect of Rotating Acoustic Stimulus on Heart Rate Variability in Healthy Adults

    OpenAIRE

    Roy, Bhaskar; Choudhuri, Raghabendra; Pandey, Ambarish; Bandopadhyay, Sajal; Sarangi, Sasmit; Kumar Ghatak, Sobhendu

    2012-01-01

    Acoustic stimulus can modulate the Autonomic Nervous System. However, previous reports on this topic are conflicting and inconclusive. In this study we have shown, how rotating acoustic stimulus, a novel auditory binaural stimulus, can change the autonomic balance of the cardiac system. We have used Heart rate Variability (HRV), an indicator of autonomic modulation of heart, both in time and frequency domain to analyze the effect of stimulus on 31 healthy adults.

  20. 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.

  1. Ivabradine Improves Heart Rate Variability in Patients with Nonischemic Dilated Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Ertugrul Kurtoglu

    2014-10-01

    Full Text Available Background: Ivabradine is a novel specific heart rate (HR-lowering agent that improves event-free survival in patients with heart failure (HF. Objectives: We aimed to evaluate the effect of ivabradine on time domain indices of heart rate variability (HRV in patients with HF. Methods: Forty-eight patients with compensated HF of nonischemic origin were included. Ivabradine treatment was initiated according to the latest HF guidelines. For HRV analysis, 24-h Holter recording was obtained from each patient before and after 8 weeks of treatment with ivabradine. Results: The mean RR interval, standard deviation of all normal to normal RR intervals (SDNN, the standard deviation of 5-min mean RR intervals (SDANN, the mean of the standard deviation of all normal-to-normal RR intervals for all 5-min segments (SDNN index, the percentage of successive normal RR intervals exceeding 50 ms (pNN50, and the square root of the mean of the squares of the differences between successive normal to normal RR intervals (RMSSD were low at baseline before treatment with ivabradine. After 8 weeks of treatment with ivabradine, the mean HR (83.6 ± 8.0 and 64.6 ± 5.8, p < 0.0001, mean RR interval (713 ± 74 and 943 ± 101 ms, p < 0.0001, SDNN (56.2 ± 15.7 and 87.9 ± 19.4 ms, p < 0.0001, SDANN (49.5 ± 14.7 and 76.4 ± 19.5 ms, p < 0.0001, SDNN index (24.7 ± 8.8 and 38.3 ± 13.1 ms, p < 0.0001, pNN50 (2.4 ± 1.6 and 3.2 ± 2.2 %, p < 0.0001, and RMSSD (13.5 ± 4.6 and 17.8 ± 5.4 ms, p < 0.0001 substantially improved, which sustained during both when awake and while asleep. Conclusion: Our findings suggest that treatment with ivabradine improves HRV in nonischemic patients with HF.

  2. Testosterone Deficiency Increases Hospital Readmission and Mortality Rates in Male Patients with Heart Failure

    Directory of Open Access Journals (Sweden)

    Marcelo Rodrigues dos Santos

    2015-01-01

    Full Text Available Background: Testosterone deficiency in patients with heart failure (HF is associated with decreased exercise capacity and mortality; however, its impact on hospital readmission rate is uncertain. Furthermore, the relationship between testosterone deficiency and sympathetic activation is unknown. Objective: We investigated the role of testosterone level on hospital readmission and mortality rates as well as sympathetic nerve activity in patients with HF. Methods: Total testosterone (TT and free testosterone (FT were measured in 110 hospitalized male patients with a left ventricular ejection fraction < 45% and New York Heart Association classification IV. The patients were placed into low testosterone (LT; n = 66 and normal testosterone (NT; n = 44 groups. Hypogonadism was defined as TT < 300 ng/dL and FT < 131 pmol/L. Muscle sympathetic nerve activity (MSNA was recorded by microneurography in a subpopulation of 27 patients. Results: Length of hospital stay was longer in the LT group compared to in the NT group (37 ± 4 vs. 25 ± 4 days; p = 0.008. Similarly, the cumulative hazard of readmission within 1 year was greater in the LT group compared to in the NT group (44% vs. 22%, p = 0.001. In the single-predictor analysis, TT (hazard ratio [HR], 2.77; 95% confidence interval [CI], 1.58–4.85; p = 0.02 predicted hospital readmission within 90 days. In addition, TT (HR, 4.65; 95% CI, 2.67–8.10; p = 0.009 and readmission within 90 days (HR, 3.27; 95% CI, 1.23–8.69; p = 0.02 predicted increased mortality. Neurohumoral activation, as estimated by MSNA, was significantly higher in the LT group compared to in the NT group (65 ± 3 vs. 51 ± 4 bursts/100 heart beats; p < 0.001. Conclusion: These results support the concept that LT is an independent risk factor for hospital readmission within 90 days and increased mortality in patients with HF. Furthermore, increased MSNA was observed in patients with LT.

  3. Testosterone Deficiency Increases Hospital Readmission and Mortality Rates in Male Patients with Heart Failure

    Science.gov (United States)

    dos Santos, Marcelo Rodrigues; Sayegh, Ana Luiza Carrari; Groehs, Raphaela Vilar Ramalho; Fonseca, Guilherme; Trombetta, Ivani Credidio; Barretto, Antônio Carlos Pereira; Arap, Marco Antônio; Negrão, Carlos Eduardo; Middlekauff, Holly R.; Alves, Maria-Janieire de Nazaré Nunes

    2015-01-01

    Background Testosterone deficiency in patients with heart failure (HF) is associated with decreased exercise capacity and mortality; however, its impact on hospital readmission rate is uncertain. Furthermore, the relationship between testosterone deficiency and sympathetic activation is unknown. Objective We investigated the role of testosterone level on hospital readmission and mortality rates as well as sympathetic nerve activity in patients with HF. Methods Total testosterone (TT) and free testosterone (FT) were measured in 110 hospitalized male patients with a left ventricular ejection fraction < 45% and New York Heart Association classification IV. The patients were placed into low testosterone (LT; n = 66) and normal testosterone (NT; n = 44) groups. Hypogonadism was defined as TT < 300 ng/dL and FT < 131 pmol/L. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography in a subpopulation of 27 patients. Results Length of hospital stay was longer in the LT group compared to in the NT group (37 ± 4 vs. 25 ± 4 days; p = 0.008). Similarly, the cumulative hazard of readmission within 1 year was greater in the LT group compared to in the NT group (44% vs. 22%, p = 0.001). In the single-predictor analysis, TT (hazard ratio [HR], 2.77; 95% confidence interval [CI], 1.58–4.85; p = 0.02) predicted hospital readmission within 90 days. In addition, TT (HR, 4.65; 95% CI, 2.67–8.10; p = 0.009) and readmission within 90 days (HR, 3.27; 95% CI, 1.23–8.69; p = 0.02) predicted increased mortality. Neurohumoral activation, as estimated by MSNA, was significantly higher in the LT group compared to in the NT group (65 ± 3 vs. 51 ± 4 bursts/100 heart beats; p < 0.001). Conclusion These results support the concept that LT is an independent risk factor for hospital readmission within 90 days and increased mortality in patients with HF. Furthermore, increased MSNA was observed in patients with LT. PMID:26200897

  4. 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 fr...

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

    Directory of Open Access Journals (Sweden)

    Toshio Matsuoka

    2005-03-01

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

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

    Science.gov (United States)

    Petelczyc, M; Zebrowski, J J; Baranowski, R; Chojnowska, L

    2010-12-01

    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. PMID:21071828

  7. 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

  8. 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

  9. 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…

  10. 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

  11. Relationship between heart rate recovery and inflammatory markers in patients with polycystic ovary syndrome: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Giallauria Francesco

    2009-02-01

    Full Text Available Abstract Background Polycystic ovary syndrome (PCOS is an endocrine disease closely related to several risk factors for cardiovascular disease. An abnormal heart rate recovery (HRR, an easily-obtained measure derived from exercise stress test and closely related to an increased risk for cardiovascular mortality, has been recently described in PCOS women. A subclinical increase of the inflammation markers has been also observed in the PCOS. This study was designed to study the relationships between HRR and inflammatory markers in PCOS women. Methods Two-hundred forty-three young PCOS patients without known risk factors for cardiovascular risk were enrolled. All patients underwent hormonal and metabolic profile, white blood cells (WBCs count and C-reactive protein (CRP. HRR was calculated as the difference between heart rate at peak exercise and heart rate at first minute of the cool-down period. Abnormal HRR was defined as ?18 beats/min for standard exercise testing. Results Eighty-nine out of 243 patients presented abnormal HRR. Serum CRP (1.8 ± 0.7 vs. 1.1 ± 0.4 mg/dl, p 9 cells/l, p versus normal HRR. HRR was significantly associated with both CRP (r = -0.33, p p Conclusion Abnormal HRR and inflammatory markers are closely associated in PCOS women acting probably in concert to increase the cardiovascular risk profile of these patients.

  12. 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.

  13. 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 u...

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

    OpenAIRE

    Oberdörster Günter; Mykins Betty; Couderc Jean; Rückerl Regina; Schneider Raphael; Schmidt Georg; Zareba Wojciech; Ibald-Mulli Angela; Hampel Regina; Schneider Alexandra; Wölke Gabriele; Pitz Mike; Wichmann H -Erich; Peters Annette

    2010-01-01

    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 Apri...

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

    Directory of Open Access Journals (Sweden)

    Mohammed

    2015-05-01

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

  16. 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.

  17. 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.

  18. On the nature of heart rate variability in a breathing normal subject: a stochastic process analysis.

    Science.gov (United States)

    Buchner, Teodor; Petelczyc, Monika; Zebrowski, Jan J; Prejbisz, Aleksander; Kabat, Marek; Januszewicz, Andrzej; Piotrowska, Anna Justyna; Szelenberger, Waldemar

    2009-06-01

    Human heart rate is moderated by the autonomous nervous system acting predominantly through the sinus node (the main cardiac physiological pacemaker). One of the dominant factors that determine the heart rate in physiological conditions is its coupling with the respiratory rhythm. Using the language of stochastic processes, we analyzed both rhythms simultaneously taking the data from polysomnographic recordings of two healthy individuals. Each rhythm was treated as a sum of a deterministic drift term and a diffusion term (Kramers-Moyal expansion). We found that normal heart rate variability may be considered as the result of a bidirectional coupling of two nonlinear oscillators: the heart itself and the respiratory system. On average, the diffusion (noise) component measured is comparable in magnitude to the oscillatory (deterministic) term for both signals investigated. The application of the Kramers-Moyal expansion may be useful for medical diagnostics providing information on the relation between respiration and heart rate variability. This interaction is mediated by the autonomous nervous system, including the baroreflex, and results in a commonly observed phenomenon--respiratory sinus arrhythmia which is typical for normal subjects and often impaired by pathology. PMID:19566279

  19. Observations and Modeling of Unusual Patterns in Human Heart Rate Variability

    International Nuclear Information System (INIS)

    We investigate nonlinear instabilities in human heart rate variability. We focus on phenomena with characteristic, easily recognizable features which are well known in physics. In the past we were able to show two groups of evidence. The first was an ever expanding roster of such cases of heart rate variability pathology which exhibit type I intermittency. This phenomenon occurs in those dynamical systems which have come close to a saddle-node bifurcation. The second were observations of homoclinic orbits and the gluing bifurcation in measured heart rate variability. We present here two cases of 24-hour recordings of human heart rate which exhibit special, regular patterns. We show that period-1, period-2 orbits and homoclinic orbits may be found in return maps formed using this data. Using a pair of coupled modified van der Pol-Duffing oscillators, we are able to model the behavior of the sino-atrial node and of the atrio-ventricular node (elements of the conduction system of the heart) in such a way as to obtain orbits similar to those measured during the sino-atrial block in a human. (author)

  20. The Role of Shape and Heart Rate on the Performance of the Left Ventricle.

    Science.gov (United States)

    Song, Zeying; Borazjani, Iman

    2015-11-01

    The left ventricle function is to pump the oxygenated blood through the circulatory system. Ejection fraction is the main noninvasive parameter for detecting heart disease (healthy >55%), and it is thought to be the main parameter affecting efficiency. However, the effects of other parameters on efficiency have yet to be investigated. We investigate the effect of heart rate and left ventricle shape by carrying out 3D numerical simulations of a left ventricle at different heart rates and perturbed geometries under constant, normal ejection fraction. The simulation using the immersed boundary method provide the 3D flow and pressure fields, which enable direct calculation of a new hemodynamic efficiency (H-efficiency) parameter, which does not depend on any reference pressure. The H-efficiency is defined as the ratio of flux of kinetic energy (useful power) to the total cardiac power into the left ventricle control volume. Our simulations show that H-efficiency is not that sensitive to heart rate but is maximized at around normal heart rate (72 bpm). Nevertheless, it is more sensitive to the shape of the left ventricle, which affects the H-efficiency by as much as 15% under constant ejection fraction. PMID:26312776

  1. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kurata, Chinori; Wakabayashi, Yasushi; Shouda, Sakae; Mikami, Tadashi [Hamamatsu Medical School (Japan); Tawarahara, Kei; Sugiyama, Tsuyoshi; Nakano, Tomoyasu; Suzuki, Toshihiko

    1997-04-01

    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.)

  3. 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.

  4. Effects of concurrent physical and cognitive demands on muscle activity and heart rate variability in a repetitive upper-extremity precision task

    DEFF Research Database (Denmark)

    Srinivasan, Divya; Mathiassen, Svend Erik

    2015-01-01

    PURPOSE: Most previous studies of concurrent physical and cognitive demands have addressed tasks of limited relevance to occupational work, and with dissociated physical and cognitive task components. This study investigated effects on muscle activity and heart rate variability of executing a repetitive occupational task with an added cognitive demand integral to correct task performance. METHODS: Thirty-five healthy females performed 7.5 min of standardized repetitive pipetting work in a baseline condition and a concurrent cognitive condition involving a complex instruction for correct performance. Average levels and variabilities of electromyographic activities in the upper trapezius and extensor carpi radialis (ECR) muscles were compared between these two conditions. Heart rate and heart rate variability were also assessed to measure autonomic nervous system activation. Subjects also rated perceived fatigue in the neck-shoulder region, as well as exertion. RESULTS: Concurrent cognitive demands increased trapezius muscle activity from 8.2 % of maximum voluntary exertion (MVE) in baseline to 9.0 % MVE (p = 0.0005), but did not significantly affect ECR muscle activity, heart rate, heart rate variability, perceived fatigue or exertion. CONCLUSION: Trapezius muscle activity increased by about 10 %, without any accompanying cardiovascular response to indicate increased sympathetic activation. We suggest this slight increase in trapezius muscle activity to be due to changed muscle activation patterns within or among shoulder muscles. The results suggest that it may be possible to introduce modest cognitive demands necessary for correct performance in repetitive precision work without any major physiological effects, at least in the short term.

  5. EFFECT OF PRANAYAMA ON BLOOD PRESSURE AND HEART RATE IN HYPERREACTOR TO COLD PRESSOR TEST

    Directory of Open Access Journals (Sweden)

    Krishan Bihari

    2014-07-01

    Full Text Available INTRODUCTION: Stress is a dangerous and significant problem of World, which affects physical, mental, behavioral, and emotional health. Yoga has been reported to control stress, to be beneficial in treating stress related disorders, improving autonomic functions, lower blood pressure, increase strength and flexibility of muscles, improve the sense of well-being, slow ageing process, control breathing, reducing signs of oxidative stress and improving spiritual growth. AIMS: The aim of present study was to investigate whether regular practice of Yoga for three months can reduce the cardiovascular hyper-reactivity induced by cold pressor test. MATERIALS AND METHODS: The study group comprised 62 healthy male subjects of 17-27 years age group. Initially there were 30 hyper reactors to cold pressor test. The hyper-reactivity of 23 volunteers converted to hypo-reactivity after the yoga therapy of three months (76.66%. Other parameters like basal blood pressure, rise in blood pressure, pulse rate and rate of respiration were also statistically significantly reduced (by using student ‘t’ test. STATISTICAL ANALYSIS: 2 tail student‘t’ test was done by using the standard formulas. RESULTS: Regular practice of yoga significantly reduces the cardiovascular hyper-reactivity in basal blood pressure, rise in blood pressure after one minute of cold stress, heart rate, and rate of respiration, after three month of yoga practice. CONCLUSION: Regular practice of yoga for three months reduced the cardiovascular hyper-reactivity to cold pressor test in subjects, who were hyper reactive to cold stress, possibly by inducing parasympathetic predominance and cortico-hypothalamomedullary inhibition.

  6. Effects of concentrated ambient particles on heart rate and blood pressure in pulmonary hypertensive rats.

    Science.gov (United States)

    Cheng, Tsun-Jen; Hwang, Jing-Shiang; Wang, Peng-Yau; Tsai, Chia-Fang; Chen, Chun-Yen; Lin, Sheng-Hsiang; Chan, Chang-Chuan

    2003-02-01

    Epidemiologic studies have shown that increased concentrations of ambient particles are associated with cardiovascular morbidity and mortality. However, the exact mechanisms remain unclear. Recent studies have revealed that particulate air pollution exposure is associated with indicators of autonomic function including heart rate, blood pressure, and heart rate variability. However, this association has not been clearly demonstrated in animal studies. To overcome the problems of wide variations in diseased animals and circadian cycles, we adopted a novel approach using a mixed-effects model to investigate whether ambient particle exposure was associated with changes in heart rate and blood pressure in pulmonary hypertensive rats. Male Sprague-Dawley rats were implanted with radiotelemetry devices and exposed to concentrated ambient particles generated by an air particle concentrator. The rats were held in nose-only exposure chambers for 6 hr per day for 3 consecutive days and then rested for 4 days in each week during the experimental period of 5 weeks. These animals were exposed to concentrated particles during weeks 2, 3, and 4 and exposed to filtered air during weeks 1 and 5. The particle concentrations for tested animals ranged between 108 and 338 micro g/m(3). Statistical analysis using mixed-effects models revealed that entry and exit of exposure chamber and particle exposure were associated with changes in heart rate and mean blood pressure. Immediately after particle exposure, the hourly averaged heart rate decreased and reached the lowest at the first and second hour of exposure for a decrease of 14.9 (p particle exposure, with a maximal decrease of 3.3 (p particles might influence blood pressure and heart rate. PMID:12573896

  7. 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; Liang, Bo; Wang, Juan; Zhou, Hua; Zhuang, Shao-Wei

    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 ...

  8. 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...

  9. 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)

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

    International Nuclear Information System (INIS)

    The relationship between the myocardial uptake of iodine-123 metaiodobenzylguanidine (123I-MIBG) and heart rate variability parameters has not been determined. This study determined the relationship between the change in myocardial uptake of 123I-MIBG and improvement in left ventricular function after treatment, to determine the usefulness of 123I-MIBG imaging to assess the effect of therapy on heart failure due to dilated cardiomyopathy (DCM). 123I-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 123I-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 123I-MIBG imaging and heart rate variability parameters are useful to assess the autonomic tone in DCM with heart failure. (author)

  11. 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)

  12. 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.

  13. Breakdown of Long-Range Correlations in Heart Rate Fluctuations During Meditation

    CERN Document Server

    Papasimakis, Nikitas

    2009-01-01

    The average wavelet coefficient method is applied to investigate the scaling features of heart rate variability during meditation, a state of induced mental relaxation. While periodicity dominates the behavior of the heart rate time series at short intervals, the meditation induced correlations in the signal become significantly weaker at longer time scales. Further study of these correlations by means of an entropy analysis in the natural time domain reveals that the induced mental relaxation introduces substantial loss of complexity at larger scales, which indicates a change in the physiological mechanisms involved.

  14. 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

  15. Correlated and Uncorrelated Regions in Heart-Rate Fluctuations during Sleep

    Science.gov (United States)

    Bunde, Armin; Havlin, Shlomo; Kantelhardt, Jan W.; Penzel, Thomas; Peter, Jörg-Hermann; Voigt, Karlheinz

    2000-10-01

    Healthy sleep consists of several stages: deep sleep, light sleep, and rapid eye movement (REM) sleep. Here we show that these sleep stages can be characterized and distinguished by correlations of heart rates separated by n beats. Using the detrended fluctuation analysis (DFA) up to fourth order we find that long-range correlations reminiscent to the wake phase are present only in the REM phase. In the non-REM phases, the heart rates are uncorrelated above the typical breathing cycle time, pointing to a random regulation of the heartbeat during non-REM sleep.

  16. Radial Basis Function and K-Nearest Neighbor Classifiers for Studying Heart Rate Signals during Meditation

    OpenAIRE

    Ateke Goshvarpour; Atefeh Goshvarpour

    2012-01-01

    Meditation refers to a family of self-regulation practices that focus on training attention and awareness in order to bring mental processes under greater voluntary control. The aim of this study is to evaluate the efficiency of two different classifiers, k-Nearest Neighbor (k-NN) and Radial Basis Function (RBF), on the heart rate signals in a specific psychological state. For this purpose, two types of heart rate time series (before, and during meditation) of 25 healthy women are collected i...

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

    DEFF Research Database (Denmark)

    Mouridsen, Mette Rauhe; Bendsen, Nathalie Tommerup; Astrup, Arne; Haugaard, Steen Bendix; Binici, Zeynep; Sajadieh, Ahmad

    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-n...

  18. Quantifying Exertion Level During Exercise Stress Testing Using Percentage of Age-Predicted Maximal Heart Rate, Rate Pressure Product, and Perceived Exertion

    OpenAIRE

    Pinkstaff, Sherry; Peberdy, Mary Ann; Kontos, Michael C.; Finucane, Sheryl; Arena, Ross

    2010-01-01

    OBJECTIVE: To determine if the attainment of at least 85% of age-predicted maximal heart rate (APMHR), using the equation 220 – age, and/or at least 25,000 as the product of maximal heart rate and systolic blood pressure (rate pressure product, RPP) is an accurate indicator of exertion level during exercise stress testing.

  19. Relationship of 24-hour ambulatory blood pressure and heart rate with markers of hepatic function in cirrhotic patients

    OpenAIRE

    Stergiou George S; Dourakis Spyros P; Alexopoulou Alexandra; Tzamouranis Dimitris G

    2010-01-01

    Abstract Background There is evidence that in cirrhotic patients, certain hemodynamic parameters, such as blood pressure and heart rate, are related to the severity of liver disease. This study investigated whether non-invasive 24-hour ambulatory blood pressure and heart rate are more closely associated with markers of liver disease severity than conventional office measurements. Methods Ambulatory patients with cirrhosis underwent office blood pressure and heart rate measurements, 24-hour am...

  20. 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

  1. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Matsukawa, Seishirou [Toho Univ., Tokyo (Japan). Omori Hospital

    1998-06-01

    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 {sup 123}I-metaiodobenzylguanidine (MIBG) myocardial SPECT, after the administration of ADR. TP value, LF value, LF/HF and SDANN value were 1,448 msec{sup 2}, 354 msec{sup 2}, 2.0 and 97 msec, respectively, indicating that these values were significantly lower than the healthy controls (the C group) (P<0.01). Consecutive observation for 7 cases of ADR group revealed that TP value decreased from 1,489 msec{sup 2} to 1,058 msec{sup 2}, and HF value decreased from 191 msec{sup 2} to 123 msec{sup 2}, significantly (P<0.05). On the other hand, the washout rate of left ventricle which was estimated from MIBG myocardial SPECT increased from 22{+-}14% to 32{+-}14%, significantly (P<0.05). Though cumulative mean dosage of ADR was 286{+-}148 mg/m{sup 2}, 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 the chemotherapy. Thus it was suggested that the death by arrhythmia and the irreversible myocardial injury might be predictable. (author)

  3. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Dikkers, R. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: r.dikkers@rad.umcg.nl; Greuter, M.J.W. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: m.j.w.greuter@rad.umcg.nl; Kristanto, W. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: w.kristanto@rad.umcg.nl; Ooijen, P.M.A. van [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: p.m.a.van.ooyen@rad.umcg.nl; Sijens, P.E. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: p.e.sijens@rad.umcg.nl; Willems, T.P. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: t.p.willems@rad.umcg.nl; Oudkerk, M. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: m.oudkerk@rad.umcg.nl

    2009-04-15

    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.

  5. 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.

  6. Wireless patch sensor for remote monitoring of heart rate, respiration, activity, and falls.

    Science.gov (United States)

    Chan, Alexander M; Selvaraj, Nandakumar; Ferdosi, Nima; Narasimhan, Ravi

    2013-01-01

    Unobtrusive continuous monitoring of important vital signs and activity metrics has the potential to provide remote health monitoring, at-home screening, and rapid notification of critical events such as heart attacks, falls, or respiratory distress. This paper contains validation results of a wireless Bluetooth Low Energy (BLE) patch sensor consisting of two electrocardiography (ECG) electrodes, a microcontroller, a tri-axial accelerometer, and a BLE transceiver. The sensor measures heart rate, heart rate variability (HRV), respiratory rate, posture, steps, and falls and was evaluated on a total of 25 adult participants who performed breathing exercises, activities of daily living (ADLs), various stretches, stationary cycling, walking/running, and simulated falls. Compared to reference devices, the heart rate measurement had a mean absolute error (MAE) of less than 2 bpm, time-domain HRV measurements had an RMS error of less than 15 ms, respiratory rate had an MAE of 1.1 breaths per minute during metronome breathing, posture detection had an accuracy of over 95% in two of the three patch locations, steps were counted with an absolute error of less than 5%, and falls were detected with a sensitivity of 95.2% and specificity of 100%. PMID:24111135

  7. 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.

    2008-12-01

    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.

  8. 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 children's pulse rate from the earlobe would be more accurate, especially for tachycardia. However, we do not recommend that 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

  9. C-reactive protein, heart rate variability and prognosis in community subjects with no apparent heart disease

    DEFF Research Database (Denmark)

    Sajadieh, A; Nielsen, OW

    2006-01-01

    OBJECTIVES: Increased C-reactive protein (CRP) and reduced heart rate variability (HRV) both indicate poor prognosis. An inverse association between HRV and CRP has been reported, suggesting an interaction between inflammatory and autonomic systems. However, the prognostic impact of this interaction has not been studied. We thus investigated the prognostic impact of CRP, HRV and their combinations. DESIGN: Population-based study. SUBJECTS: A total of 638 middle-aged and elderly subjects with no apparent heart disease from community. METHODS: All were studied by clinical and laboratory examinations, and 24-h Holter monitoring. Four time domain measures of HRV were studied. All were prospectively followed for up to 5 years. RESULTS: Mean age was 64 years (55-75). During the follow-up, 46 total deaths and 11 cases of definite acute myocardial infarction were observed. Both CRP and three of four HRV measures were significantly associated with increased rate of death or myocardial infarction. In a Cox model with CRP >or=2.5 microg mL(-1), standard deviation for the mean value of the time between normal complexes

  10. 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

  11. 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.

  12. Heart Rate and Systolic Blood Pressure Variability on Recently Diagnosed Diabetics

    Directory of Open Access Journals (Sweden)

    Anaclara Michel-Chávez

    2015-01-01

    Full Text Available Background: Diabetes affects approximately 250 million people in the world. Cardiovascular autonomic neuropathy is a common complication of diabetes that leads to severe postural hypotension, exercise intolerance, and increased incidence of silent myocardial infarction. Objective: To determine the variability of heart rate (HR and systolic blood pressure (SBP in recently diagnosed diabetic patients. Methods: The study included 30 patients with a diagnosis of type 2 diabetes of less than 2 years and 30 healthy controls. We used a Finapres® device to measure during five minutes beat-to-beat HR and blood pressure in three experimental conditions: supine position, standing position, and rhythmic breathing at 0.1 Hz. The results were analyzed in the time and frequency domains. Results: In the HR analysis, statistically significant differences were found in the time domain, specifically on short-term values such as standard deviation of NN intervals (SDNN, root mean square of successive differences (RMSSD, and number of pairs of successive NNs that differ by more than 50 ms (pNN50. In the BP analysis, there were no significant differences, but there was a sympathetic dominance in all three conditions. The baroreflex sensitivity (BRS decreased in patients with early diabetes compared with healthy subjects during the standing maneuver. Conclusions: There is a decrease in HR variability in patients with early type 2 diabetes. No changes were observed in the BP analysis in the supine position, but there were changes in BRS with the standing maneuver, probably due to sympathetic hyperactivity.

  13. 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.

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

    Directory of Open Access Journals (Sweden)

    Judson A. 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.

  15. Heart Rate and Systolic Blood Pressure Variability on Recently Diagnosed Diabetics

    Science.gov (United States)

    Michel-Chávez, Anaclara; Estañol, Bruno; Gien-López, José Antonio; Robles-Cabrera, Adriana; Huitrado-Duarte, María Elena; Moreno-Morales, René; Becerra-Luna, Brayans

    2015-01-01

    Background Diabetes affects approximately 250 million people in the world. Cardiovascular autonomic neuropathy is a common complication of diabetes that leads to severe postural hypotension, exercise intolerance, and increased incidence of silent myocardial infarction. Objective To determine the variability of heart rate (HR) and systolic blood pressure (SBP) in recently diagnosed diabetic patients. Methods The study included 30 patients with a diagnosis of type 2 diabetes of less than 2 years and 30 healthy controls. We used a Finapres® device to measure during five minutes beat-to-beat HR and blood pressure in three experimental conditions: supine position, standing position, and rhythmic breathing at 0.1 Hz. The results were analyzed in the time and frequency domains. Results In the HR analysis, statistically significant differences were found in the time domain, specifically on short-term values such as standard deviation of NN intervals (SDNN), root mean square of successive differences (RMSSD), and number of pairs of successive NNs that differ by more than 50 ms (pNN50). In the BP analysis, there were no significant differences, but there was a sympathetic dominance in all three conditions. The baroreflex sensitivity (BRS) decreased in patients with early diabetes compared with healthy subjects during the standing maneuver. Conclusions There is a decrease in HR variability in patients with early type 2 diabetes. No changes were observed in the BP analysis in the supine position, but there were changes in BRS with the standing maneuver, probably due to sympathetic hyperactivity. PMID:26176187

  16. The changes of heart rate variability after unilateral stellate ganglion block

    Science.gov (United States)

    Kim, Jang Jae; Lee, Hee Seung; Han, Jong In

    2010-01-01

    Background The effect of the unilateral stellate ganglion block (SGB) on cardiovascular regulation remains controversial. We wished to evaluate the changes in heart rate variability (HRV) after a unilateral stellate ganglion block in patients with head and neck pain in the present study. Methods Patients with head and neck pain (n = 89) were studied. HRV was determined before and after a C6 unilateral stellate ganglion block (right-sided SGB, 40; left-sided SGB, 49) using a paratracheal technique with 1% mepivacaine (6 ml). Results There were no significant differences in HRV indices before and after right-sided SGB. The log scale of power in the high frequency range (lnHF) was increased and ratio of power in the low frequency range (LF) to power in the high frequency range (HF) ratio was decreased after left-sided SGB. Conclusions These results demonstrated that left-sided SGB increased parasympathetic activities in patients with head and neck pain. PMID:20498813

  17. 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

  18. The Effect of Smoking on the Baroregulatory System; Heart Rate Turbulence

    Directory of Open Access Journals (Sweden)

    Alim Erdem

    2012-04-01

    Full Text Available Introduction: Smoking has been known to cause various adverse cardiovascular reactions. Our study was conducted to demonstrate the chronic effects of smoking on baroregulatory function by using heart rate turbulence (HRT parameters among asymptomatic smokers.Materials and Methods: Sixty four smokers with histories of incessant smoking for at least one year (group 1 and 30 non-smokers (group 2 were enrolled in this study. Addiction of smoking was graded according to the modified Fagerström test for nicotine dependence (m-FNDT. Each smoker was conferred a nicotine dependence index (NDI according to the m-FNDT. The values of HRT (TO: Turbulence onset, TS: Turbulence slope were compared between two groups along with basic clinical, echocardiographic and Holter parameters. And the relationship between HRT and m-FDT was analyzed. Results: There was no significant difference the basic clinical and echocardiographic features (p> 0.05. The mean value of TO was higher significantly (p< 0.05 in group 1 than group 2, the mean values of TS was not different significantly between the two groups. The value of NDI was positively correlated with the value of TO (p< 0.05.Conclusion: Smoking impaired baroregulatory function especially in TO, even in asymptomatic smokers.

  19. Heart rate variability in early phase of acutemyocardial infarction and convalescence

    International Nuclear Information System (INIS)

    Objective: This study was done to evaluate the degree of change in autonomic activity, manifested as heart rate variability (HRV), from acute phase of MI to convalescent period of AMI. Result: The mean hospital stay was 7.07 plus minus 2.56 days. Mean duration between the two recordings was 5.45 plus minus 2.36 days. The mean standard deviation of normal sinus interval (SDNN) was 65.07 plus minus 25. 11 msec and 63-97 plus minus 23.38 msec; mean standard deviation of averaged sinus beats for 5 minutes segments of entire recording (SDANN) was 51.27 plus minus 18.57 msec and 55.83 plus minus 19.65 msec and mean SDDN index was 34.57 plus minus 17.15 msec and 30.57 plus minus 14.89 msec during early phase of acute MI and pre-discharge recordings respectively. There was no statistically significant difference in HRV between early phase of acute myocardial infarction and of pre-discharge recordings. Conclusion: HRV may be monitored for risk stratification at any time post AMI prior to discharge. (author)

  20. 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.

  1. Proposal Intensity Adequacy of Expiratory Effort and Heart Rate Behavior During the Valsalva Maneuver in Preadolescents

    Directory of Open Access Journals (Sweden)

    Mario Augusto Paschoal

    2014-08-01

    Full Text Available Background: When performing the Valsalva maneuver (VM, adults and preadolescents produce the same expiratory resistance values. Objective: To analyze heart rate (HR in preadolescents performing VM, and propose a new method for selecting expiratory resistance. Method: The maximal expiratory pressure (MEP was measured in 45 sedentary children aged 9-12 years who subsequently performed VM for 20 s using an expiratory pressure of 60%, 70%, or 80% of MEP. HR was measured before, during, and after VM. These procedures were repeated 30 days later, and the data collected in the sessions (E1, E2 were analyzed and compared in periods before, during (0-10 and 10-20 s, and after VM using nonparametric tests. Results: All 45 participants adequately performed VM in E1 and E2 at 60% of MEP. However, only 38 (84.4% and 25 (55.5% of the participants performed the maneuver at 70% and 80% of MEP, respectively. The HR delta measured during 0-10 s and 10-20 s significantly increased as the expiratory effort increased, indicating an effective cardiac autonomic response during VM. However, our findings suggest the VM should not be performed at these intensities. Conclusion: HR increased with all effort intensities tested during VM. However, 60% of MEP was the only level of expiratory resistance that all participants could use to perform VM. Therefore, 60% of MEP may be the optimal expiratory resistance that should be used in clinical practice.

  2. Design and evaluation of a handheld impedance plethysmograph for measuring heart rate variability

    DEFF Research Database (Denmark)

    Kristiansen, N K; Fleischer, Jesper

    2005-01-01

    Heart rate variability (HRV) analysis from 10s ECGs has been shown to be reliable. However, the short examination time warrants a user-friendly system that can be used for ad-hoc examinations without normal preparation, unlike ECG. A handheld device has been developed that can measure ultra-short HRV from impedance plethysmographic recordings of the pulse wave in distal superficial arteries. The prototype device was made user-friendly through a compact, pen-like design and the use of integrated metal electrodes that were especially designed for dry operation. The main signal processing was performed by a digital signal processor, where the discrete heart beats were detected using a correlation algorithm that could adapt to individual pulse wave shapes to account for biological variation. The novel device was evaluated in 20 mainly young volunteers, using 10 s time-correlated ECG recordings as the reference method. Agreement between the two methods in measuring heart rate and root mean square of successive differences in the heart beat interval (RMSSD) was analysed using correlation coefficients (Pearson's R2), mean differences with 95% confidence intervals and 95% limits of agreement, and Bland-Altman plots. The correlation between the two methods was R2 = 1.00 and R2 = 0.99 when heart rate and RMSSD were measured, respectively. The Bland-Altman plots showed suitable agreement between the novel device and standard 10 s ECGs, which was substantiated by 95% limits of agreement of the difference of +/- 0.1 beats min(-1) and approximately +/- 10 ms for heart rate and RMSSD, respectively. Therefore the evaluation showed no significant systematic error of the novel device compared with ECG.

  3. 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

  4. 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 ( p<0.01 ). This parameter can be used to estimate autonomic depression caused by aging and heart 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.

  5. Influence of Load Intensity on Postexercise Hypotension and Heart Rate Variability after a Strength Training Session.

    Science.gov (United States)

    Figueiredo, Tiago; Willardson, Jeffrey M; Miranda, Humberto; Bentes, Claudio M; Reis, Victor M; Simão, Roberto

    2015-10-01

    Figueiredo, T, Willardson, JM, Miranda, H, Bentes, CM, Reis, VM, and Simão, R. Influence of load intensity on postexercise hypotension and heart rate variability after a strength training session. J Strength Cond Res 29(10): 2941-2948, 2015-The purpose of this study was to compare blood pressure and heart rate variability (HRV) responses in trained men after strength training (ST) sessions with loads of 60, 70, and 80% of a 1 repetition maximum (1RM). Eleven men (age: 26.1 ± 3.6 years; body mass: 74.1 ± 8.1 kg; height: 172.0 ± 4.0 cm; body mass index: 25.0 ± 1.96 kg·m; %G: 18.3 ± 6.4) with at least 6-month ST experience participated in this study. After assessment of 1RM loads for the bench press (BP), lat pull-down (LPD), shoulder press (SP), biceps curl (BC), triceps extension (TE), leg press (LP), leg extension (LE), and leg curl (LC), subjects performed 3 experimental sessions in random order. During each experimental session, subjects performed 3 sets of 8-10 repetitions at 60, 70, or 80% of 1RM loads, with 2-minute rest intervals between sets and exercises. All experimental sessions were performed in the following exercise order: BP, LPD, SP, BC, TE, LP, LE, and LC. Before and for 1 hour after each experimental session, blood pressure and HRV were tracked. The results demonstrated a greater duration of postexercise hypotension (PEH) after the 70% of 1RM session vs. the 60 or 80% of 1RM session. These results indicate that the load/volume associated with completion of 8-10 repetitions at 70% of 1RM load may provide the best stimulus for the PEH response when compared with training with a 60 or 80% of 1RM loads. In conclusion, strength and conditioning professionals may prescribe exercises with 60, 70, and 80% of 1RM loads if the intent is to elicit an acute decrease in blood pressure after an ST session; however, 70% of 1RM provides a longer PEH. PMID:25807024

  6. The Effects of Musical Auditory Stimulation of Different Intensities on Geometric Indices of Heart Rate Variability.

    Science.gov (United States)

    do Amaral, Joice Anaize Tonon; Guida, Heraldo Lorena; Vanderlei, Franciele Marques; Garner, David Matthew; de Abreu, Luiz Carlos; Valenti, Vitor Engracia

    2015-09-01

    Background • Music has been proven to promote changes in cardiac autonomic modulation. However, it is not clear whether the effects of the auditory stimulation on heart rate variability (HRV) are dependent on its intensity. Objective • The study intended to investigate the acute effects on the geometric HRV indices of auditory stimulation with heavy metal and baroque music using different intensities of auditory stimulation. Design • The study was a nonrandomized, clinical trial. Setting • The study was conducted at the facility of the Faculty of Sciences of the São Paulo State University, on the campus in Marilia, Brazil. Participants • Participants were 24 healthy women aged between 18 and 27 y. Intervention • HRV was recorded for each participant for 10 min at rest. Subsequently, participants were exposed to baroque or heavy metal music through an earphone. They were exposed to 3 equivalent sound levels-60-70 decibels (dB), 70-80 dB, and 80-90 dB-for 5 min in each intensity range. After the first session of baroque or heavy metal music, participants rested for an additional 5 min. Then they were exposed to the other musical style. The first style played for each musical period was randomly selected for all individuals and then the other style would be played automatically for the second session. Outcome Measures • The HRV analysis was performed using the following geometrical methods: (1) the triangular index (RRtri), (2) the triangular interpolation of the RR interval histogram (TINN), and (3) the Poincaré plot, using SD1-the standard deviation of the instantaneous variability of the beat-to beat heart rate (HR), SD2-the standard deviation of the long-term, continuous, RR interval variability, and the SD1/SD2 ratio-the ratio between the short- and long-term variations among the RR intervals. Results • The classic baroque music by Johann Pachelbel, "Canon in D Major," did not induce significant changes in the geometric indices of HRV at 60-70 dB, 70-80 dB, or 80-90 dB. However, auditory stimulation with heavy metal music, using "Heavy Metal Universe" by Gamma Ray, decreased the RRtri, TINN, and SD2 at 2 specific sound pressures (60-70 dB and 80-90 dB). Conclusions • Auditory stimulation with the selected baroque music did not alter cardiac autonomic modulation, but the selected, heavy metal style of music in the lower and higher intensities reduced the global component of HRV acutely. PMID:26393987

  7. Heart rate variability indices in the time domain in healthy dogs supplemented with omega n-3

    Directory of Open Access Journals (Sweden)

    Thiago Hideky Yamauti dos Santos

    2014-09-01

    Full Text Available The analysis of heart rate variability (HRV in the time domain was performed by dynamic electrocardiographic monitoring for twenty-four hours (Holter method in ten male and ten female healthy mixed-breed dogs before and after four weeks of oral supplementation with long-chain polyunsaturated fatty acids (PUFAs derived from omega n-3 [497 mg docosahexaenoic acid (DHA and 780 mg eicosapentaenoic acid (EPA]. Males received an average dose of 34.9 mg DHA/kg and 22.2 mg EPA/kg, whereas females received an average of 27 mg DHA/kg and 43 mg EPA/kg. HRV indices calculated in the time domain were the following: NN, SDNN, SDANN, SDNN index, pNN50, rMSSD and heart rate, taking into account the effects of gender and supplementation. The results showed no significant effects of supplementation or gender on the indices; thus, dietary supplementation with omega PUFAs derived from n-3 over four weeks did not decrease heart rate and did not increase heart rate variability in healthy dogs.

  8. Augmented baroreflex heart rate gain after moderate-intensity, dynamic exercise

    Science.gov (United States)

    Halliwill, J. R.; Taylor, J. A.; Hartwig, T. D.; Eckberg, D. L.

    1996-01-01

    The occurrence of a sustained vasodilation and hypotension after acute, dynamic exercise suggests that exercise may alter arterial baroreflex mechanisms. Therefore, we assessed systemic hemodynamics, baroreflex regulation of heart rate, and cardiac vagal tone after 60 min of cycling at 60% peak oxygen consumption in 12 healthy, untrained men and women (ages 21-28 yr). We derived sigmoidal carotid-cardiac baroreflex relations by measurement of R-R interval changes induced by ramped, stepwise, R-wave-triggered changes in external neck pressure from 40 to -65 mmHg. We estimated tonic cardiac vagal control with power spectral analysis of R-R interval variability in the respiratory frequency band (0.2-0.3 Hz) during frequency- and tidal volume-controlled breathing. Both mean arterial pressure and total peripheral resistance were reduced postexercise [pressure: from 86 +/- 2 (mean +/- SE) to 81 +/- 2 mmHg; resistance: from 23 +/- 2 to 16 +/- 1 units; both P exercise, whereas heart rate and plasma norepinephrine levels were elevated. Thus moderate-intensity, dynamic exercise increases heart rate and cardiac output, reduces peripheral vascular resistance, and augments baroreflex responsiveness. Our data suggest that augmented baroreflex heart rate gain restrains rather than contributes to postexercise hypotension, which appears to be mediated predominately by vasodilation.

  9. Electronic Motion Sensors and Heart Rate as Measures of Physical Activity in Children.

    Science.gov (United States)

    Freedson, Patty S.

    1991-01-01

    Reviews several mechanical and electronic techniques for monitoring physical activity in children. The paper focuses on motion sensors (Large Scale Integrated Sensor and Caltrac Accelerometer) and heart rate, and it presents recommendations for establishing general guidelines for appropriate use of such monitoring devices with children. (SM)

  10. 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

  11. Influence of vagus nerve stimulator to systemic blood pressure and heart rate measurement.

    Czech Academy of Sciences Publication Activity Database

    Jurák, Pavel; Kára, T.; Halámek, Josef; Kuba, R.; Chládek, Jan; Vondra, Vlastimil

    Liptovský Mikuláš : Vojenská Akadémia FZV, 2002 - (Puttera, J.), s. 96 - 99 ISBN 80-8040-180-2. [KTERP. Tatranské Zruby (SK), 24.04.2002-26.04.2002] R&D Projects: GA ?R GA102/00/1262 Institutional research plan: CEZ:AV0Z2065902 Keywords : Vagus Nerve Stimulation * heart rate * blood pressure Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  12. 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…

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

    International Nuclear Information System (INIS)

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

  14. Pupillary and Heart Rate Reactivity in Children with Minimal Brain Dysfunction

    Science.gov (United States)

    Zahn, Theodore P.; And Others

    1978-01-01

    In an attempt to replicate and extend previous findings on autonomic arousal and responsivity in children with minimal brain dysfunction (MBD), pupil size, heart rate, skin conductance, and skin temperature were recorded from 32 MBD and 45 control children (6-13 years old). (Author/CL)

  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. 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 Disease s incl. Cardiotharic Surgery

  17. 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.

  18. Heart rate and estimated energy expenditure of flapping and gliding in black-browed albatrosses.

    Science.gov (United States)

    Sakamoto, Kentaro Q; Takahashi, Akinori; Iwata, Takashi; Yamamoto, Takashi; Yamamoto, Maki; Trathan, Philip N

    2013-08-15

    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 melanophrys) to estimate the energy cost of flapping as well as time spent in flapping activities. The heart rate of albatrosses during flight (144 beats min(-1)) was similar to that while sitting on the water (150 beats min(-1)). In contrast, heart rate was much higher during takeoff and landing (ca. 200 beats min(-1)). Heart rate during cruising flight was linearly correlated with the number of wing flaps per minute, suggesting an extra energy burden of flapping. Albatrosses spend only 4.6±1.4% of their time flapping during cruising flight, which was significantly lower than during and shortly after takeoff (9.8±3.5%). Flapping activity, which amounted to just 4.6% of the time in flight, accounted for 13.3% of the total energy expenditure during cruising flight. These results support the idea that albatrosses achieve energy-efficient flight by reducing the time spent in flapping activity, which is associated with high energy expenditure. PMID:23661772

  19. Heart rate and blood lactate concentration of male road-race motorcyclists.

    Science.gov (United States)

    D'Artibale, Emanuele; Tessitore, Antonio; Capranica, Laura

    2008-05-01

    Although motorcycling performance strongly depends on the characteristics of the motorcycles and capabilities of the riders, little information is available on the physiological profiles of riders. The aim of this study was to evaluate the physical load of official international men's road-race motorcycling competitions. Data were obtained from 34 male riders during the 2005 European Road-Race Motorcycling Championship (categories classified by size of engine: 125 GP, 250 GP, and 600 cc) during free practices, qualifying sessions, and official races. Participants' heart rates were recorded and blood lactate concentrations determined. During races, heart rates were most often above 90% of maximum heart rate (frequency of occurrence: 125 GP = 92.9%, s = 5.3; 250 GP = 93.6%, s = 7.3; 600 cc = 93.2%, s = 10.2). The heart rate distribution during riding showed main effects between phases of competition, engine sizes, and different portions of the race (P motorcycling imposes a high load on the riders, who should possess adequate fitness to maintain high-speed rides and minimize the effects of fatigue during competition. PMID:18409099

  20. 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.)

  1. Modeling heart rate regulation--part II: parameter identification and analysis.

    Science.gov (United States)

    Fowler, K R; Gray, G A; Olufsen, M S

    2008-06-01

    In part I of this study we introduced a 17-parameter model that can predict heart rate regulation during postural change from sitting to standing. In this subsequent study, we focus on the 17 model parameters needed to adequately represent the observed heart rate response. In part I and in previous work (Olufsen et al. 2006), we estimated the 17 model parameters by minimizing the least squares error between computed and measured values of the heart rate using the Nelder-Mead method (a simplex algorithm). In this study, we compare the Nelder-Mead optimization method to two sampling methods: the implicit filtering method and a genetic algorithm. We show that these off-the-shelf optimization methods can work in conjunction with the heart rate model and provide reasonable parameter estimates with little algorithm tuning. In addition, we make use of the thousands of points sampled by the optimizers in the course of the minimization to perform an overall analysis of the model itself. Our findings show that the resulting least-squares problem has multiple local minima and that the non-linear-least squares error can vary over two orders of magnitude due to the complex interaction between the model parameters, even when provided with reasonable bound constraints. PMID:18172764

  2. HEART RATE VARIABILITY IN RODENTS — USES AND CAVEATS IN TOXICOLOGICAL STUDIES

    Science.gov (United States)

    Heart rate variability (HRV) is a measure of cardiac pacing dynamics that has recently garnered a great deal of interest in environmental health studies. While the use of these measures has become popular, much uncertainty remains in the interpretation of results, both in terms ...

  3. The Use of Heart Rate Variability as a Novel Method to Differentiate between Affective States

    Science.gov (United States)

    The major goal of animal welfare scientists is to determine when animals are experiencing a state of good welfare or poor welfare. The goal of this research was to determine if measures of heart rate variability can be used to differentiate whether animals are experiencing ‘unpleasant’ versus ‘pleas...

  4. 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...

  5. 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.,…

  6. Effect of Icodextrin on Heart Rate Variability in Diabetic Patients on Peritoneal Dialysis

    OpenAIRE

    Orihuela, Oscar; de Jesús Ventura, María; Ávila-Díaz, Marcela; Cisneros, Alejandra; Vicenté-Martínez, Marlén; Furlong, María-del-Carmen; García-González, Zuzel; Villanueva, Diana; Alcántara, Guadalupe; Lindholm, Bengt; García-López, Elvia; Villanueva, Cleva; Paniagua, Ramón

    2014-01-01

    ? Introduction: Spectral analysis of heart rate variability is a noninvasive method for evaluating autonomic cardiovascular dysfunction under various clinical conditions, such as in dialysis patients, in whom an imbalance between the sympathetic and parasympathetic nervous system appears to be an important risk factor for sudden cardiovascular death and arrhythmia.

  7. Radial Basis Function and K-Nearest Neighbor Classifiers for Studying Heart Rate Signals during Meditation

    Directory of Open Access Journals (Sweden)

    Ateke Goshvarpour

    2012-05-01

    Full Text Available Meditation refers to a family of self-regulation practices that focus on training attention and awareness in order to bring mental processes under greater voluntary control. The aim of this study is to evaluate the efficiency of two different classifiers, k-Nearest Neighbor (k-NN and Radial Basis Function (RBF, on the heart rate signals in a specific psychological state. For this purpose, two types of heart rate time series (before, and during meditation of 25 healthy women are collected in the meditation clinic in Mashhad. The spectral parameters are used to gain insight into the autonomic nervous system (ANS response induced by meditation. Therefore, very low frequency, low frequency, high frequency, the LF/HF ratio and frequency of the highest spectral peak of heart rate signals are extracted and used as inputs of the classifiers. To evaluate performance of the classifiers, the classification accuracies and mean square error (MSE of the classifiers were examined. The classification results of this study denote that the RBF classifier trained on spectral features obtains higher accuracy than that of k-NN classifier. The total classification accuracy of the RBF classifier is 92.3% with 0.026 classification error. However, k-Nearest Neighbor classifier gives encouraging results (86.5%. Experimental results verify that radial basis function is an efficient classifier for classifying heart rate signals in a specific psychological state.

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

    Energy Technology Data Exchange (ETDEWEB)

    Salvucci, Fernando Pablo; Schiavone, Jonathan; Craiem, Damian; Barra, Juan Gabriel [Facultad de Ingenieria y Ciencias Exactas y Naturales, Universidad Favaloro Av. Belgrano 1723 - Buenos Aires (Argentina)

    2007-11-15

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

  9. Field Validity of Heart Rate Variability Metrics Produced by QRSTool and CMetX

    Science.gov (United States)

    Hibbert, Anita S.; Weinberg, Anna; Klonsky, E. David

    2012-01-01

    Interest in heart rate variability (HRV) metrics as markers of physiological and psychological health continues to grow beyond those with psychophysiological expertise, increasing the importance of developing suitable tools for researchers new to the field. Allen, Chambers, and Towers (2007) developed QRSTool and CMetX software as simple,…

  10. DOES FEEDBACK FROM A NEST AFFECT PERIPARTURIENT BEHAVIOUR, HORMONES AND HEART RATE IN GILTS?

    Science.gov (United States)

    To determine the effects of feedback from a farrowing nest on sow welfare, as determined by behaviour, hormones and heart rate, 20 gilts housed in central-nest-farrowing-pens were permitted to build a nest of peat, straw and branches. Ten sows then had their nest removed (NR) 10h after the onset of ...

  11. Childhood Psychopathology and Autonomic Dysregulation: Exploring the Links Using Heart Rate Variability

    Science.gov (United States)

    Srinivasan, Krishnamachari

    2007-01-01

    Changes in cardiovascular reactivity have been used as a psychophysiological marker of various emotional states in both children and adults. Recent decades have seen increasing use of heart rate variability as a non-invasive marker of cardiac autonomic function and of central processes involved in autonomic function regulation. Developmental…

  12. Effects of a Group Contingency Strategy on Middle School Physical Education Students' Heart Rates

    Science.gov (United States)

    Vidoni, Carla; Azevedo, Liane; Eberline, Andrew

    2012-01-01

    The purpose of this study was to assess the effects of a dependent group contingency on eighth-grade students' heart rates. Participants were 18 male and female students. A multielement research design was used to examine the intervention effects. The intervention consisted of: (a) teacher explanation about effort; (b) students' suggestions to…

  13. The Effect of Listening to Specific Musical Genre Selections on Measures of Heart Rate Variability

    Science.gov (United States)

    Orman, Evelyn K.

    2011-01-01

    University students (N = 30) individually listened to the Billboard 100 top-ranked musical selection for their most and least liked musical genre. Two minutes of silence preceded each musical listening condition, and heart rate variability (HRV) was recorded throughout. All HRV measures decreased during music listening as compared with silence.…

  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. Stuttered and Fluent Speakers' Heart Rate and Skin Conductance in Response to Fluent and Stuttered Speech

    Science.gov (United States)

    Zhang, Jianliang; Kalinowski, Joseph; Saltuklaroglu, Tim; Hudock, Daniel

    2010-01-01

    Background: Previous studies have found simultaneous increases in skin conductance response and decreases in heart rate when normally fluent speakers watched and listened to stuttered speech compared with fluent speech, suggesting that stuttering induces arousal and emotional unpleasantness in listeners. However, physiological responses of persons…

  16. Heart Rate Complexity in Response to Upright Tilt in Persons with Down Syndrome

    Science.gov (United States)

    Agiovlasitis, Stamatis; Baynard, Tracy; Pitetti, Kenneth H.; Fernhall, Bo

    2011-01-01

    People with Down syndrome (DS) show altered autonomic response to sympatho-excitation. Cardiac autonomic modulation may be examined with heart rate (HR) complexity which is associated uniquely with cardiovascular risk. This study examined whether the response of HR complexity to passive upright tilt differs between persons with and without DS and…

  17. 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

  18. 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.…

  19. 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…

  20. Validity of the Smarthealth Watch to Measure Heart Rate during Rest and Exercise

    Science.gov (United States)

    Lee, C. Matthew; Gorelick, Mark

    2011-01-01

    The purpose of this study was to examine the validity of the Smarthealth watch (Salutron, Inc., Fremont, California, USA), a heart rate monitor that includes a wristwatch without an accompanying chest strap. Twenty-five individuals participated in 3-min periods of standing, 2.0 mph walking, 3.5 mph walking, 4.5 mph jogging, and 6.0 mph running.…