WorldWideScience

Sample records for normal heart rhythm

  1. Find a Heart Rhythm Specialist

    Science.gov (United States)

    ... Taiwan Thailand Turkey United Arab Emirates United Kingdom Venezuela Vietnam Within 5 miles 10 miles 15 miles ... info@HRSonline.org © Heart Rhythm Society 2017 Privacy Policy | Linking Policy | Patient Education Disclaimer You are about ...

  2. Determination of Sample Entropy and Fuzzy Measure Entropy Parameters for Distinguishing Congestive Heart Failure from Normal Sinus Rhythm Subjects

    Directory of Open Access Journals (Sweden)

    Lina Zhao

    2015-09-01

    Full Text Available Entropy provides a valuable tool for quantifying the regularity of physiological time series and provides important insights for understanding the underlying mechanisms of the cardiovascular system. Before any entropy calculation, certain common parameters need to be initialized: embedding dimension m, tolerance threshold r and time series length N. However, no specific guideline exists on how to determine the appropriate parameter values for distinguishing congestive heart failure (CHF from normal sinus rhythm (NSR subjects in clinical application. In the present study, a thorough analysis on the selection of appropriate values of m, r and N for sample entropy (SampEn and recently proposed fuzzy measure entropy (FuzzyMEn is presented for distinguishing two group subjects. 44 long-term NRS and 29 long-term CHF RR interval recordings from http://www.physionet.org were used as the non-pathological and pathological data respectively. Extreme (>2 s and abnormal heartbeat RR intervals were firstly removed from each RR recording and then the recording was segmented with a non-overlapping segment length N of 300 and 1000, respectively. SampEn and FuzzyMEn were performed for each RR segment under different parameter combinations: m of 1, 2, 3 and 4, and r of 0.10, 0.15, 0.20 and 0.25 respectively. The statistical significance between NSR and CHF groups under each combination of m, r and N was observed. The results demonstrated that the selection of m, r and N plays a critical role in determining the SampEn and FuzzyMEn outputs. Compared with SampEn, FuzzyMEn shows a better regularity when selecting the parameters m and r. In addition, FuzzyMEn shows a better relative consistency for distinguishing the two groups, that is, the results of FuzzyMEn in the NSR group were consistently lower than those in the CHF group while SampEn were not. The selections of m of 2 and 3 and r of 0.10 and 0.15 for SampEn and the selections of m of 1 and 2 whenever r (herein

  3. Chaos control applied to heart rhythm dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Borem Ferreira, Bianca, E-mail: biaborem@gmail.com [Universidade Federal do Rio de Janeiro, COPPE, Department of Mechanical Engineering, P.O. Box 68.503, 21.941.972 Rio de Janeiro, RJ (Brazil); Souza de Paula, Aline, E-mail: alinedepaula@unb.br [Universidade de Brasi' lia, Department of Mechanical Engineering, 70.910.900 Brasilia, DF (Brazil); Amorim Savi, Marcelo, E-mail: savi@mecanica.ufrj.br [Universidade Federal do Rio de Janeiro, COPPE, Department of Mechanical Engineering, P.O. Box 68.503, 21.941.972 Rio de Janeiro, RJ (Brazil)

    2011-08-15

    Highlights: > A natural cardiac pacemaker is modeled by a modified Van der Pol oscillator. > Responses related to normal and chaotic, pathological functioning of the heart are investigated. > Chaos control methods are applied to avoid pathological behaviors of heart dynamics. > Different approaches are treated: stabilization of unstable periodic orbits and chaos suppression. - Abstract: The dynamics of cardiovascular rhythms have been widely studied due to the key aspects of the heart in the physiology of living beings. Cardiac rhythms can be either periodic or chaotic, being respectively related to normal and pathological physiological functioning. In this regard, chaos control methods may be useful to promote the stabilization of unstable periodic orbits using small perturbations. In this article, the extended time-delayed feedback control method is applied to a natural cardiac pacemaker described by a mathematical model. The model consists of a modified Van der Pol equation that reproduces the behavior of this pacemaker. Results show the ability of the chaos control strategy to control the system response performing either the stabilization of unstable periodic orbits or the suppression of chaotic response, avoiding behaviors associated with critical cardiac pathologies.

  4. Circadian rhythm in idiopathic normal pressure hydrocephalus.

    Science.gov (United States)

    Eleftheriou, Andreas; Ulander, Martin; Lundin, Fredrik

    2018-01-01

    The pathogenesis of idiopathic normal pressure hydrocephalus (iNPH) takes place in structures close to the cerebral ventricular system. Suprachiasmatic nucleus (SCN), situated close to the third ventricle, is involved in circadian rhythm. Diurnal disturbances are well-known in demented patients. The cognitive decline in iNPH is potentially reversible after a shunt operation. Diurnal rhythm has never been studied in iNPH. We hypothesize that there is a disturbance of circadian rhythm in iNPH-patients and the aim was to study any changes of the diurnal rhythm (mesor and circadian period) as well as any changes of the diurnal amplitude and acrophase of the activity in iNPH-patients before and after a shunt operation. Twenty consecutive iNPH-patients fulfilling the criteria of the American iNPH-guidelines, 9 males and 11 females, mean age 73 (49-81) years were included. The patients underwent a pre-operative clinical work-up including 10m walk time (w10mt) steps (w10ms), TUG-time (TUGt) and steps (TUGs) and for cognitive function an MMSE score was measured. In order to receive circadian rhythm data actigraphic recordings were performed using the SenseWear 2 (BodyMedia Inc Pittsburgh, PA, USA) actigraph. Cosinor analyses of accelerometry data were performed in "R" using non-linear regression with Levenburg- Marquardt estimation. Pre- and post-operative data regarding mesor, amplitude and circadian period were compared using Wilcoxon-Mann-Whitney test for paired data. Twenty patients were evaluated before and three month post-operatively. Motor function (w10mt, w10ms, TUGt, TUGs) was significantly improved while MMSE was not significantly changed. Actigraphic measurements (mesor, amplitude and circadian period) showed no significant changes after shunt operation. This is the first systematic study of circadian rhythm in iNPH-patients. We found no significant changes in circadian rhythm after shunt surgery. The conceptual idea of diurnal rhythm changes in hydrocephalus is

  5. Strength of Gamma Rhythm Depends on Normalization

    Science.gov (United States)

    Ray, Supratim; Ni, Amy M.; Maunsell, John H. R.

    2013-01-01

    Neuronal assemblies often exhibit stimulus-induced rhythmic activity in the gamma range (30–80 Hz), whose magnitude depends on the attentional load. This has led to the suggestion that gamma rhythms form dynamic communication channels across cortical areas processing the features of behaviorally relevant stimuli. Recently, attention has been linked to a normalization mechanism, in which the response of a neuron is suppressed (normalized) by the overall activity of a large pool of neighboring neurons. In this model, attention increases the excitatory drive received by the neuron, which in turn also increases the strength of normalization, thereby changing the balance of excitation and inhibition. Recent studies have shown that gamma power also depends on such excitatory–inhibitory interactions. Could modulation in gamma power during an attention task be a reflection of the changes in the underlying excitation–inhibition interactions? By manipulating the normalization strength independent of attentional load in macaque monkeys, we show that gamma power increases with increasing normalization, even when the attentional load is fixed. Further, manipulations of attention that increase normalization increase gamma power, even when they decrease the firing rate. Thus, gamma rhythms could be a reflection of changes in the relative strengths of excitation and normalization rather than playing a functional role in communication or control. PMID:23393427

  6. An analysis of heart rhythm dynamics using a three-coupled oscillator model

    International Nuclear Information System (INIS)

    Gois, Sandra R.F.S.M.; Savi, Marcelo A.

    2009-01-01

    Rhythmic phenomena represent one of the most striking manifestations of the dynamic behavior in biological systems. Understanding the mechanisms responsible for biological rhythms is crucial for the comprehension of the dynamics of life. Natural rhythms could be either regular or irregular over time and space. Each kind of dynamical behavior may be related to both normal and pathological physiological functioning. The cardiac conducting system can be treated as a network of self-excitatory elements and, since these elements exhibit oscillatory behavior, they can be modeled as nonlinear oscillators. This paper proposes a mathematical model to describe heart rhythms considering three modified Van der Pol oscillators connected with time delay couplings. Therefore, the heart dynamics is represented by a system of differential difference equations. Numerical simulations are carried out presenting qualitative agreement with the general heart rhythm behavior. Normal and pathological rhythms represented by the ECG signals are reproduced. Pathological rhythms are generated by either the coupling alterations that represents communications aspects in the heart electric system or forcing excitation representing external pacemaker excitation.

  7. Estimation of Circadian Body Temperature Rhythm Based on Heart Rate in Healthy, Ambulatory Subjects.

    Science.gov (United States)

    Sim, Soo Young; Joo, Kwang Min; Kim, Han Byul; Jang, Seungjin; Kim, Beomoh; Hong, Seungbum; Kim, Sungwan; Park, Kwang Suk

    2017-03-01

    Core body temperature is a reliable marker for circadian rhythm. As characteristics of the circadian body temperature rhythm change during diverse health problems, such as sleep disorder and depression, body temperature monitoring is often used in clinical diagnosis and treatment. However, the use of current thermometers in circadian rhythm monitoring is impractical in daily life. As heart rate is a physiological signal relevant to thermoregulation, we investigated the feasibility of heart rate monitoring in estimating circadian body temperature rhythm. Various heart rate parameters and core body temperature were simultaneously acquired in 21 healthy, ambulatory subjects during their routine life. The performance of regression analysis and the extended Kalman filter on daily body temperature and circadian indicator (mesor, amplitude, and acrophase) estimation were evaluated. For daily body temperature estimation, mean R-R interval (RRI), mean heart rate (MHR), or normalized MHR provided a mean root mean square error of approximately 0.40 °C in both techniques. The mesor estimation regression analysis showed better performance than the extended Kalman filter. However, the extended Kalman filter, combined with RRI or MHR, provided better accuracy in terms of amplitude and acrophase estimation. We suggest that this noninvasive and convenient method for estimating the circadian body temperature rhythm could reduce discomfort during body temperature monitoring in daily life. This, in turn, could facilitate more clinical studies based on circadian body temperature rhythm.

  8. Dynamic correlations between heart and brain rhythm during Autogenic meditation

    OpenAIRE

    Kim, Dae-Keun; Lee, Kyung-Mi; Kim, Jongwha; Whang, Min-Cheol; Kang, Seung Wan

    2013-01-01

    This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha pow...

  9. Core temperature rhythms in normal and tumor-bearing mice.

    Science.gov (United States)

    Griffith, D J; Busot, J C; Lee, W E; Djeu, D J

    1993-01-01

    The core temperature temporal behavior of DBA/2 mice (11 normal and 13 with an ascites tumor) was studied using surgically implanted radio telemetry transmitters. Normal mice continuously displayed a stable 24 hour temperature rhythm. Tumor-bearers displayed a progressive deterioration of the temperature rhythm following inoculation with tumor cells. While such disruptions have been noted by others, details on the dynamics of the changes have been mostly qualitative, often due to time-averaging or steady-state analysis of the data. The present study attempts to quantify the dynamics of the disruption of temperature rhythm (when present) by continuously monitoring temperatures over periods up to a month. Analysis indicated that temperature regulation in tumor-bearers was adversely affected during the active period only. Furthermore, it appears that the malignancy may be influencing temperature regulation via pathways not directly attributable to the energy needs of the growing tumor.

  10. Rhythm-based heartbeat duration normalization for atrial fibrillation detection.

    Science.gov (United States)

    Islam, Md Saiful; Ammour, Nassim; Alajlan, Naif; Aboalsamh, Hatim

    2016-05-01

    Screening of atrial fibrillation (AF) for high-risk patients including all patients aged 65 years and older is important for prevention of risk of stroke. Different technologies such as modified blood pressure monitor, single lead ECG-based finger-probe, and smart phone using plethysmogram signal have been emerging for this purpose. All these technologies use irregularity of heartbeat duration as a feature for AF detection. We have investigated a normalization method of heartbeat duration for improved AF detection. AF is an arrhythmia in which heartbeat duration generally becomes irregularly irregular. From a window of heartbeat duration, we estimate the possible rhythm of the majority of heartbeats and normalize duration of all heartbeats in the window based on the rhythm so that we can measure the irregularity of heartbeats for both AF and non-AF rhythms in the same scale. Irregularity is measured by the entropy of distribution of the normalized duration. Then we classify a window of heartbeats as AF or non-AF by thresholding the measured irregularity. The effect of this normalization is evaluated by comparing AF detection performances using duration with the normalization, without normalization, and with other existing normalizations. Sensitivity and specificity of AF detection using normalized heartbeat duration were tested on two landmark databases available online and compared with results of other methods (with/without normalization) by receiver operating characteristic (ROC) curves. ROC analysis showed that the normalization was able to improve the performance of AF detection and it was consistent for a wide range of sensitivity and specificity for use of different thresholds. Detection accuracy was also computed for equal rates of sensitivity and specificity for different methods. Using normalized heartbeat duration, we obtained 96.38% accuracy which is more than 4% improvement compared to AF detection without normalization. The proposed normalization

  11. Dynamic correlations between heart and brain rhythm during Autogenic meditation

    Science.gov (United States)

    Kim, Dae-Keun; Lee, Kyung-Mi; Kim, Jongwha; Whang, Min-Cheol; Kang, Seung Wan

    2013-01-01

    This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but weak opposite relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion. PMID:23914165

  12. Dynamic correlations between heart and brain rhythm during Autogenic meditation

    Directory of Open Access Journals (Sweden)

    Daekeun eKim

    2013-07-01

    Full Text Available This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but, again, no significant relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion.

  13. Dynamic correlations between heart and brain rhythm during Autogenic meditation.

    Science.gov (United States)

    Kim, Dae-Keun; Lee, Kyung-Mi; Kim, Jongwha; Whang, Min-Cheol; Kang, Seung Wan

    2013-01-01

    This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but weak opposite relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion.

  14. Resonance of about-weekly human heart rate rhythm with solar activity change.

    Science.gov (United States)

    Cornelissen, G; Halberg, F; Wendt, H W; Bingham, C; Sothern, R B; Haus, E; Kleitman, E; Kleitman, N; Revilla, M A; Revilla, M; Breus, T K; Pimenov, K; Grigoriev, A E; Mitish, M D; Yatsyk, G V; Syutkina, E V

    1996-12-01

    In several human adults, certain solar activity rhythms may influence an about 7-day rhythm in heart rate. When no about-weekly feature was found in the rate of change in sunspot area, a measure of solar activity, the double amplitude of a circadian heart rate rhythm, approximated by the fit of a 7-day cosine curve, was lower, as was heart rate corresponds to about-weekly features in solar activity and/or relates to a sunspot cycle.

  15. Effects of atomoxetine on heart rhythm in children and adolescents.

    Science.gov (United States)

    Tanidir, Ibrahim Cansaran; Tanidir, Canan; Ozturk, Erkut; Bahali, Kayhan; Gunes, Hatice; Ergul, Yakup; Uneri, Ozden Sukran; Akdeniz, Celal; Tuzcu, Volkan

    2015-12-01

    The aim of this study was to examine the effects of atomoxetine on heart rhythm using 12-lead electrocardiography (ECG) and 24 h Holter monitoring. Children and adolescents who were diagnosed with attention deficit-hyperactivity disorder according to DSM-IV-TR were referred to a pediatric cardiology clinic for cardiologic examination before and after 4 or 5 weeks of atomoxetine treatment. Cardiac examination, complete blood count, biochemistry, thyroid function tests, 12-lead ECG and 24 h Holter monitoring were performed routinely in all patients. Each subject underwent 24 h Holter ECG monitoring before atomoxetine was started and after 4 or 5 weeks of effective dose atomoxetine treatment. Forty-one patients were included in this prospective study. No statistically significant change was found in QT, QTc or QT interval dispersion or blood pressure before and after 4 or 5 weeks of atomoxetine treatment. There was a statistically significant increase in heart rate (both during the day and at night) and QRS duration, and a statistically significant decrease in P wave dispersion. Three patients had rhythm disturbances. All of these three patients were asymptomatic and none of these arrhythmias reached clinical significance. Atomoxetine did not cause significant changes in ECG or Holter variables. In two patients, who had undiagnosed subclinical extrasystoles, extra beats were increased after 4th week of treatment, but still remained clinically insignificant. Before and after atomoxetine treatment, listening to the heart sounds for a longer time, may help clinicians to notice an extra beat. If an extra beat is identified then 24 Holter monitoring is recommended. © 2015 Japan Pediatric Society.

  16. Pharmacologic Rhythm Control versus Rate Control in Heart Failure and Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Gladys Gladys

    2017-01-01

    Full Text Available Heart failure (HF with atrial fibrillation (AF is correlated with worse prognosis requiring special approach.Rate control has been the first line of treatment in cases of HF and HF. On the other hand, rhythm controlhas been proven to be effective in returning sinus rhythm resulting in better prognosis for patients with HFbut not HF. Its role in cocurring cases of HF and AF is not fully understood. Thus, this study aims to analysewhether pharmacologic rhythm control can be applied to cases of HF and AF to reduce mortality. A searchwas conducted via PubMed, Medline, ProQuest, and Cochrane Database on January 2016. One study wasselected after filtering process by inclusion and exclusion criteria and critical appraisal was performed. It wasfound that there was rhythm control and rate control do no have favouring effect towards mortality shown byRR 1.03 (95% CI 0.90-1.17, p=0.69. Rate control has protective effect towards hospitalizations by RR of 0.92(95% CI 0.86 – 0.98, p=0.008, NNT=19. To conclude, rhythm control is not superior to rate control in reducingmortality and rate control should be still be considered as first line treatment of HF and AF. Keywords: heart failure, pharmacologic rhythm control, rate control, atrial fibrillation   Farmakologis Rhythm Control Dibandingkan dengan Rate Control padaKasus Gagal Jantung dan Atrial Fibrilasi Abstrak Gagal jantung dengan atrial fibrilasi berhubungan dengan prognosis yang lebih buruk dan membutuhkanpenanganan khusus. Saat ini strategi rate control merupakan terapi lini pertama pada kasus gagal jantungdan atrial fibrilasi. Rhythm control memberikan prognosis yang lebih baik pada pasien gagal jantung denganmengembalikan sinus ritme. Kegunaan rhythm control pada kasus gagal jantung dan atrial fibrilasi sampaisaat ini belum sepenuhnya dimengerti. Tujuan studi ini adalah menelaah apakah terapi farmakologis rhythmcontrol dapat menurunkan mortalitas gagal jantung dan atrial fibrilasi. Pencarian data

  17. Influence of diuretic therapy on the features of heart rhythm variability changes in chronic heart failure patients

    Directory of Open Access Journals (Sweden)

    K R Alyeva

    2018-02-01

    Full Text Available Aim. To study comparative influence of furosemide and torasemide on heart rhythm variability in patients with chronic heart failure of ischemic origin. Methods. The study included 48 patients (29 males and 19 females with ischemic heart disease complicated by chronic heart failure, NYHA functional classes II-IV. All patients were randomized into two groups: group 1 (25 patients received furosemide as diuretic therapy, and group 2 (23 patients received torasemide. All patient underwent clinical examination including assessment of complaints and physical examination, laboratory and instrumental tests (electrocardiography, echocardiography, 6-minute walk test, 24 Hour Holter ECG monitoring before and 30 days after starting diuretic therapy. Results. Against the background of one-month diuretic therapy, positive dynamics of clinical parameters was registered in both main groups of patients receiving both furosemide and torasemide. In furosemide group deterioration of heart rhythm variability was observed. Torasemide treatment resulted in considerable improvement of vegetative regulation of heart activity. Conclusion. Diuretic therapy with furosemide is characterized by changes of time and spectral parameters of vegetative regulation of heart rhythm towards strengthening of sympathetic and attenuation of parasympathetic influence; diuretic therapy with torasemide resulted in considerable improvement of heart rhythm variability parameters, attenuation of sympathetic and strengthening of parasympathetic influence on heart rhythm that provides additional cardioprotection in the treatment of patients with chronic heart failure of ischemic origin.

  18. Frailty syndrome in patients with heart rhythm disorders.

    Science.gov (United States)

    Mlynarska, Agnieszka; Mlynarski, Rafal; Golba, Krzysztof S

    2017-09-01

    To assess the prevalence of frailty syndrome in patients with heart rhythm disorders that qualified for pacemaker implantation. The study included 171 patients (83 women, aged 73.9 ± 6.7 years) who qualified for pacemaker implantation as a result of sinus node dysfunction (81 patients) or atrio-ventricular blocks (AVB; 90 patients). A total of 60 patients (25 women, aged 72.40 ± 7.09 years) without heart rhythm disorders were included in the control group. Frailty syndrome was diagnosed using the Canadian Study of Health and Aging Clinical Frailty Scale test. Frailty syndrome was diagnosed in 25.15% of the patients, and pre-frailty in 36.84% of the patients. Frailty syndrome was diagnosed in 10% of the control group, and the average value of frailty was 3.35 ± 0.92. Frailty occurred significantly more often among patients with AVB (33.34%) compared with patients who were diagnosed with sinus node dysfunction (16.05%); P = 0.0081. The average score of frailty for sinus node dysfunction was 3.71 ± 0.89, and for AVB it was 4.14 ± 0.93; P = 0.0152. In the case of AVB, the women had a statistically more intense level of frailty of 4.54 ± 0.90 as compared with the men 3.87 ± 0.85; P = 0.0294. In the multiple logistic analysis, the presence of any arrhythmia was strongly associated with frailty syndrome (OR 2.1286, 95% CI 1.4594 - 3.1049; P = 0.0001). Frailty syndrome was diagnosed in one-quarter of patients with cardiac arrhythmias, whereas a further 40% were at a higher risk of frailty syndrome, and its occurrence was significantly higher if compared with the control group. Frailty occurred significantly more often among patients with atrio-ventricular blocks, especially in women. The results of the present research showed that there is a statistical association between frailty and arrhythmias. Geriatr Gerontol Int 2017; 17: 1313-1318. © 2016 Japan Geriatrics Society.

  19. Proceedings from Heart Rhythm Society’s Emerging Technologies Forum

    Science.gov (United States)

    Zeitler, Emily P.; Al-Khatib, Sana M.; Slotwiner, David; Kumar, Uday N.; Varosy, Paul; Van Wagoner, David R.; Marcus, Gregory M.; Kusumoto, Fred M.; Blum, Laura

    2015-01-01

    Physicians are in an excellent position to significantly contribute to medical device innovation, but the process of bringing an idea to the bedside is complex. To begin to address these perceived barriers, the Heart Rhythm Society (HRS) convened a forum of stakeholders in medical device innovation in conjunction with the 2015 HRS Scientific Sessions. The forum facilitated open discussion about medical device innovation, including obstacles to physician involvement and possible solutions. This report is based on the themes that emerged. First, physician innovators must take an organized approach to identifying unmet clinical needs and potential solutions. Second, extensive funds, usually secured through solicitation for investment, are often required to achieve meaningful progress developing an idea into a device. Third, planning for regulatory requirements of the U.S. Food & Drug Administration (FDA) and Centers for Medicare and Medicaid Services (CMS) is essential. In addition to these issues, intellectual property and overall trends in health care, including international markets, are critically relevant considerations for the physician innovator. Importantly, there are a number of ways in which professional societies can assist physician innovators to navigate the complex medical device innovation landscape, bring clinically meaningful devices to market more quickly, and ultimately improve patient care. These efforts include facilitating interaction between potential collaborators through scientific meetings and other gatherings; collecting, evaluating, and disseminating state-of-the-art scientific information; and representing the interests of members in interactions with regulators and policy makers. PMID:26801401

  20. Deciphering the Function of the Blunt Circadian Rhythm of Melatonin in the Newborn Lamb: Impact on Adrenal and Heart.

    Science.gov (United States)

    Seron-Ferre, Maria; Torres-Farfan, Claudia; Valenzuela, Francisco J; Castillo-Galan, Sebastian; Rojas, Auristela; Mendez, Natalia; Reynolds, Henry; Valenzuela, Guillermo J; Llanos, Anibal J

    2017-09-01

    Neonatal lambs, as with human and other neonates, have low arrhythmic endogenous levels of melatonin for several weeks until they start their own pineal rhythm of melatonin production at approximately 2 weeks of life. During pregnancy, daily rhythmic transfer of maternal melatonin to the fetus has important physiological roles in sheep, nonhuman primates, and rats. This melatonin rhythm provides a circadian signal and also participates in adjusting the physiology of several organs in preparation for extrauterine life. We propose that the ensuing absence of a melatonin rhythm plays a role in neonatal adaptation. To test this hypothesis, we studied the effects of imposing a high-amplitude melatonin rhythm in the newborn lamb on (1) clock time-related changes in cortisol and plasma variables and (2) clock time-related changes of gene expression of clock genes and selected functional genes in the adrenal gland and heart. We treated newborn lambs with a daily oral dose of melatonin (0.25 mg/kg) from birth to 5 days of age, recreating a high-amplitude melatonin rhythm. This treatment suppressed clock time-related changes of plasma adrenocorticotropic hormone, cortisol, clock gene expression, and functional genes in the newborn adrenal gland. In the heart, it decreased heart/body weight ratio, increased expression of Anp and Bnp, and resulted in different heart gene expression from control newborns. The interference of this postnatal melatonin treatment with the normal postnatal pattern of adrenocortical function and heart development support a physiological role for the window of flat postnatal melatonin levels during the neonatal transition. Copyright © 2017 Endocrine Society.

  1. Heart rhythm analysis using ECG recorded with a novel sternum based patch technology

    DEFF Research Database (Denmark)

    Saadi, Dorthe Bodholt; Fauerskov, Inge; Osmanagic, Armin

    2013-01-01

    , reliable long-term ECG recordings. The device is designed for high compliance and low patient burden. This novel patch technology is CE approved for ambulatory ECG recording of two ECG channels on the sternum. This paper describes a clinical pilot study regarding the usefulness of these ECG signals...... for heart rhythm analysis. A clinical technician with experience in ECG interpretation selected 200 noise-free 7 seconds ECG segments from 25 different patients. These 200 ECG segments were evaluated by two medical doctors according to their usefulness for heart rhythm analysis. The first doctor considered...... 98.5% of the segments useful for rhythm analysis, whereas the second doctor considered 99.5% of the segments useful for rhythm analysis. The conclusion of this pilot study indicates that two channel ECG recorded on the sternum is useful for rhythm analysis and could be used as input to diagnosis...

  2. Value of digoxin in heart failure and sinus rhythm : New features of an old drug?

    NARCIS (Netherlands)

    vanVeldhuisen, DJ; deGraeff, PA; Remme, WJ

    1996-01-01

    Digoxin has been a controversial drug since its introduction >200 years ago. Although its efficacy in patients with heart failure and atrial fibrillation is clear, its value in patients with heart failure and sinus rhythm has often been questioned. In the 1980s, reports of some large-scale trials

  3. Executive Summary: European Heart Rhythm Association Consensus Document on the Management of Supraventricular Arrhythmias: Endorsed by Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardiaca y Electrofisiologia (SOLAECE).

    Science.gov (United States)

    Katritsis, Demosthenes G; Boriani, Giuseppe; Cosio, Francisco G; Jais, Pierre; Hindricks, Gerhard; Josephson, Mark E; Keegan, Roberto; Knight, Bradley P; Kuck, Karl-Heinz; Lane, Deirdre A; Lip, Gregory Yh; Malmborg, Helena; Oral, Hakan; Pappone, Carlo; Themistoclakis, Sakis; Wood, Kathryn A; Young-Hoon, Kim; Lundqvist, Carina Blomström

    2016-01-01

    This paper is an executive summary of the full European Heart Rhythm Association (EHRA) consensus document on the management of supraventricular arrhythmias, published in Europace . It summarises developments in the field and provides recommendations for patient management, with particular emphasis on new advances since the previous European Society of Cardiology guidelines. The EHRA consensus document is available to read in full at http://europace.oxfordjournals.org.

  4. Reorganization of the Brain and Heart Rhythm During Autogenic Meditation

    OpenAIRE

    Dae-Keun eKim; Dae-Keun eKim; Jyoo-Hi eRhee; Seung Wan eKang; Seung Wan eKang

    2014-01-01

    The underlying changes in heart coherence that are associated with reported EEG changes in response to meditation have been explored. We measured EEG and heart rate variability (HRV) before and during autogenic meditation. Fourteen subjects participated in the study. Heart coherence scores were significantly increased during meditation compared to the baseline. We found near significant decrease in high beta absolute power, increase in alpha relative power and significant increases in lower(a...

  5. Reorganization of the brain and heart rhythm during autogenic meditation

    OpenAIRE

    Kim, Dae-Keun; Rhee, Jyoo-Hi; Kang, Seung Wan

    2014-01-01

    The underlying changes in heart coherence that are associated with reported EEG changes in response to meditation have been explored. We measured EEG and heart rate variability (HRV) before and during autogenic meditation. Fourteen subjects participated in the study. Heart coherence scores were significantly increased during meditation compared to the baseline. We found near significant decrease in high beta absolute power, increase in alpha relative power and significant increases in lower (...

  6. 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.

  7. Atrial Fibrillation: When the heart is not in rhythm | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Atrial Fibrillation Atrial Fibrillation: When the heart is not in rhythm Past ... show, Deal With It . Photo: TBS/Deal Understanding Atrial Fibrillation Atrial fibrillation (AFib) is the most common type ...

  8. 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.

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

    International Nuclear Information System (INIS)

    Luecke, Christian; Andres, Claudia; Foldyna, Borek; Nagel, Hans Dieter; Hoffmann, Janine; Grothoff, Matthias; Nitzsche, Stefan; Gutberlet, Matthias; Lehmkuhl, Lukas

    2012-01-01

    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

  10. Reorganization of the brain and heart rhythm during autogenic meditation.

    Science.gov (United States)

    Kim, Dae-Keun; Rhee, Jyoo-Hi; Kang, Seung Wan

    2014-01-13

    The underlying changes in heart coherence that are associated with reported EEG changes in response to meditation have been explored. We measured EEG and heart rate variability (HRV) before and during autogenic meditation. Fourteen subjects participated in the study. Heart coherence scores were significantly increased during meditation compared to the baseline. We found near significant decrease in high beta absolute power, increase in alpha relative power and significant increases in lower (alpha) and higher (above beta) band coherence during 3~min epochs of heart coherent meditation compared to 3~min epochs of heart non-coherence at baseline. The coherence and relative power increase in alpha band and absolute power decrease in high beta band could reflect relaxation state during the heart coherent meditation. The coherence increase in the higher (above beta) band could reflect cortico-cortical local integration and thereby affect cognitive reorganization, simultaneously with relaxation. Further research is still needed for a confirmation of heart coherence as a simple window for the meditative state.

  11. Reorganization of the Brain and Heart Rhythm During Autogenic Meditation

    Directory of Open Access Journals (Sweden)

    Dae-Keun eKim

    2014-01-01

    Full Text Available The underlying changes in heart coherence that are associated with reported EEG changes in response to meditation have been explored. We measured EEG and heart rate variability (HRV before and during autogenic meditation. Fourteen subjects participated in the study. Heart coherence scores were significantly increased during meditation compared to the baseline. We found near significant decrease in high beta absolute power, increase in alpha relative power and significant increases in lower(alpha and higher(above beta band coherence during 3 minute epochs of heart coherent meditation compared to 3 minute epochs of heart noncoherence at baseline. The coherence and relative power increase in alpha band and absolute power decrease in high beta band could reflect relaxation state during the heart coherent meditation. The coherence increase in the higher(above beta band could reflect cortico-cortical local integration and thereby affect cognitive reorganization, simultaneously with relaxation. Further research is still needed for a confirmation of heart coherence as a simple window for the meditative state.

  12. Tracking social rhythms of the heart: from dataism to art

    Directory of Open Access Journals (Sweden)

    Veera Mustonen

    2013-11-01

    Full Text Available The authors conducted a curiosity-driven study to explore what a vast body of self-tracking data could reveal about the rhythms of everyday life. The authors instructed thirty-six research participants to engage in self-tracking for a week. They measured their physiological stress and recovery 24/7 for this period. In addition to that the participants recorded their subjective experiences of stress and recovery. Using different methods of analysis and interviews, the authors were able to form data sets demonstrating both individual behaviour and interpretations of the data and the collective rhythms of all the participants. Their analysis contrasted the aggregate-level 'big data' of all the participants and the personal-level 'small data'. People’s subjective evaluations of their stress and recovery systematically differed from the physiological measurements. The big data revealed behavioural patterns and causalities that were not recognized at the individual level. The small data, on the other hand, offered rich material for personal interpretations and reflections of the individuals' own lives. To communicate both levels of the data the science project resorted to artistic expressions.

  13. The daily rhythm of body temperature, heart and respiratory rate in newborn dogs.

    Science.gov (United States)

    Piccione, Giuseppe; Giudice, Elisabetta; Fazio, Francesco; Mortola, Jacopo P

    2010-08-01

    We asked whether, during the postnatal period, the daily patterns of body temperature (Tb), heart rate (HR) and breathing frequency (f) begin and develop in synchrony. To this end, measurements of HR, f and Tb were performed weekly, on two consecutive days, for the first two postnatal months on puppies of three breeds of dogs (Rottweiler, Cocker Spaniel and Carlino dogs) with very different birth weights and postnatal growth patterns. Ambient conditions and feeding habits were constant for all puppies. The results indicated that (1) the 24-h average Tb increased and average HR and f decreased with growth, (2) the daily rhythms in Tb were apparent by 4 weeks, irrespective of the puppy's growth pattern, (3) the daily rhythm of Tb in the puppy was not necessarily following that of the mother; in fact, it could anticipate it. (4) The daily rhythms in HR and f were not apparent for the whole study period. We conclude that in neonatal dogs the onset of the daily rhythms of Tb has no obvious relationship with body size or rate of growth and is not cued by the maternal Tb rhythm. The daily rhythms of HR and f do not appear before 2 months of age. Hence, they are not in synchrony with those of Tb.

  14. European Heart Rhythm Association (EHRA) position paper on arrhythmia management and device therapies in endocrine disorders, endorsed by Asia Pacific Heart Rhythm Society (APHRS) and Latin American Heart Rhythm Society (LAHRS).

    Science.gov (United States)

    Gorenek, Bulent; Boriani, Giuseppe; Dan, Gheorge-Andrei; Fauchier, Laurent; Fenelon, Guilherme; Huang, He; Kudaiberdieva, Gulmira; Lip, Gregory Y H; Mahajan, Rajiv; Potpara, Tatjana; Ramirez, Juan David; Vos, Marc A; Marin, Francisco

    2018-03-16

    Endocrine disorders are associated with various tachyarrhythmias, including atrial fibrillation (AF), ventricular tachycardia (VT), ventricular fibrillation (VF), and bradyarrhythmias. Along with underlying arrhythmia substrate, electrolyte disturbances, glucose, and hormone levels, accompanying endocrine disorders contribute to development of arrhythmia. Arrhythmias may be life-threatening, facilitate cardiogenic shock development and increase mortality. The knowledge on the incidence of tachy- and bradyarrhythmias, clinical and prognostic significance as well as their management is limited; it is represented in observational studies and mostly in case reports on management of challenging cases. It should be also emphasized, that the topic is not covered in detail in current guidelines. Therefore, cardiologists and multidisciplinary teams participating in care of such patients do need the evidence-based, or in case of limited evidence expert-opinion based recommendations, how to treat arrhythmias using contemporary approaches, prevent their complications and recurrence in patients with endocrine disorders. In recognizing this close relationship between endocrine disorders and arrhythmias, the European Heart Rhythm Association (EHRA) convened a Task Force, with representation from Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLAECE), with the remit of comprehensively reviewing the available evidence and publishing a joint consensus document on endocrine disorders and cardiac arrhythmias, and providing up-to-date consensus recommendations for use in clinical practice.

  15. Exercises in anatomy: the normal heart.

    Science.gov (United States)

    Anderson, Robert H; Sarwark, Anne; Spicer, Diane E; Backer, Carl L

    2014-01-01

    In the first of our exercises in anatomy, created for the Multimedia Manual of the European Association of Cardiothoracic Surgery, we emphasized that thorough knowledge of intracardiac anatomy was an essential part of the training for all budding cardiac surgeons, explaining how we had used the archive of congenitally malformed hearts maintained at Lurie Children's Hospital in Chicago to prepare a series of videoclips, demonstrating the salient features of tetralogy of Fallot. In this series of videoclips, we extend our analysis of the normal heart, since for our initial exercise we had concentrated exclusively on the structure of the right ventricular outflow tract. We begin our overview of normal anatomy by emphasizing the need, in the current era, to describe the heart in attitudinally appropriate fashion. Increasingly, clinicians are demonstrating the features of the heart as it is located within the body. It is no longer satisfactory, therefore, to describe these components in a 'Valentine' fashion, as continues to be the case in most textbooks of normal or cardiac anatomy. We then emphasize the importance of the so-called morphological method, which states that structures within the heart should be defined on the basis of their own intrinsic morphology, and not according to other parts, which are themselves variable. We continue by using this concept to show how it is the appendages that serve to distinguish between the atrial chambers, while the apical trabecular components provide the features to distinguish the ventricles. We then return to the cardiac chambers, emphasizing features of surgical significance, in particular the locations of the cardiac conduction tissues. We proceed by examining the cardiac valves, and conclude by providing a detailed analysis of the septal structures. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  16. Changes in Heart Rhythm and Breathing in Acute Systemic Injury Due to Cold

    Directory of Open Access Journals (Sweden)

    D. Yu. Konnov

    2015-01-01

    Full Text Available Objective: to reveal the patterns of a change in heart rhythm and breathing in patients with acute systemic injury due to cold in hypothermic and early posthypothermic periods.Subjects and methods. Thirty patients aged 18 to 60 years (3 groups of 10 patients with mild, moderate, and severe cold injury were examined in hypothermic and posthypothermic periods. The patient groups did not differ in gender, age, and weight. Within the first 24 hours after admission, all the patients underwent high-resolution Holter electrocardiographic monitoring that recorded cardiac arrhythmias and breathing disorders.Results. During the therapy performed, as the degree of acute systemic cold injury increased, the patients were found to have a heart rate reduction (from 102 [90; 122] beats/min in Group 1 to 49 [38; 58] beats/min in Group 3 and a circadian index increase (from 105 [88; 125]% in Group 1 to 210 [185; 223]% in Group 3. With increased hypothermia, the victims were detected to have progressive cardiac rhythm and cardiac electrical conduction disturbances, such as supraventricular pacemaker migration, single and paired supraventricular premature beats, paroxysmal atrial tachycardia, atrial fibrillations, and ventricular premature beats. There was decreased heart rhythm variability in all the study groups, to the greatest extent in the patents with severe systemic cold injury. Late ventricular potentials were found in 2 and 7 patients with moderate and severe cold injury, respectively. Breathing disorders were recorded in all the study groups, the greatest increase in the frequency and duration of apnea/hypopnea episodes was noted in the patients with severe hypothermia. A fatal outcome occurred in 4 of the 10 patients with critical hypothermia due to the occurrence of idioventricular rhythm with transition to asystole.Conclusion. Systemic hypothermia is accompanied by cardiac rhythm and cardiac electrical conduction disturbances and respiratory depression

  17. [Estimation of the atrioventricular time interval by pulse Doppler in the normal fetal heart].

    Science.gov (United States)

    Hamela-Olkowska, Anita; Dangel, Joanna

    2009-08-01

    To assess normative values of the fetal atrioventricular (AV) time interval by pulse-wave Doppler methods on 5-chamber view. Fetal echocardiography exams were performed using Acuson Sequoia 512 in 140 singleton fetuses at 18 to 40 weeks of gestation with sinus rhythm and normal cardiac and extracardiac anatomy. Pulsed Doppler derived AV intervals were measured from left ventricular inflow/outflow view using transabdominal convex 3.5-6 MHz probe. The values of AV time interval ranged from 100 to 150 ms (mean 123 +/- 11.2). The AV interval was negatively correlated with the heart rhythm (page of gestation (p=0.007). However, in the same subgroup of the fetal heart rate there was no relation between AV intervals and gestational age. Therefore, the AV intervals showed only the heart rate dependence. The 95th percentiles of AV intervals according to FHR ranged from 135 to 148 ms. 1. The AV interval duration was negatively correlated with the heart rhythm. 2. Measurement of AV time interval is easy to perform and has a good reproducibility. It may be used for the fetal heart block screening in anti-Ro and anti-La positive pregnancies. 3. Normative values established in the study may help obstetricians in assessing fetal abnormalities of the AV conduction.

  18. Black Holes Are The Rhythm at The Heart of Galaxies

    Science.gov (United States)

    2008-11-01

    The powerful black holes at the center of massive galaxies and galaxy clusters act as hearts to the systems, pumping energy out at regular intervals to regulate the growth of the black holes themselves, as well as star formation, according to new data from NASA's Chandra X-Ray Observatory. People Who Read This Also Read... Milky Way’s Giant Black Hole Awoke from Slumber 300 Years Ago A New Way To Weigh Giant Black Holes Discovery of Most Recent Supernova in Our Galaxy NASA Unveils Cosmic Images Book in Braille for Blind Readers Scientists from the University of Michigan, the Max-Planck Institute for Extraterrestrial Physics in Germany, the University of Maryland, Baltimore County (UMBC), the Harvard-Smithsonian Center for Astrophysics and Jacobs University in Germany contributed to the results. The gravitational pull of black holes is so strong that not even light can escape from them. Supermassive black holes with masses of more than a billion suns have been detected at the center of large galaxies. The material falling on the black holes causes sporadic or isolated bursts of energy, by which black holes are capable of influencing the fate of their host galaxies. The insight gained by this new research shows that black holes can pump energy in a gentler and rhythmic fashion, rather then violently. The scientists observed and simulated how the black hole at the center of elliptical galaxy M84 dependably sends bubbles of hot plasma into space, heating up interstellar space. This heat is believed to slow both the formation of new stars and the growth of the black hole itself, helping the galaxy remain stable. Interstellar gases only coalesce into new stars when the gas is cool enough. The heating is more efficient at the sites where it is most needed, the scientists say. Alexis Finoguenov, of UMBC and the Max-Planck Institute for Extraterrestrial Physics in Germany, compares the central black hole to a heart muscle. "Just like our hearts periodically pump our

  19. Circadian Rhythm Neuropeptides in Drosophila: Signals for Normal Circadian Function and Circadian Neurodegenerative Disease.

    Science.gov (United States)

    He, Qiankun; Wu, Binbin; Price, Jeffrey L; Zhao, Zhangwu

    2017-04-21

    Circadian rhythm is a ubiquitous phenomenon in many organisms ranging from prokaryotes to eukaryotes. During more than four decades, the intrinsic and exogenous regulations of circadian rhythm have been studied. This review summarizes the core endogenous oscillation in Drosophila and then focuses on the neuropeptides, neurotransmitters and hormones that mediate its outputs and integration in Drosophila and the links between several of these (pigment dispersing factor (PDF) and insulin-like peptides) and neurodegenerative disease. These signaling molecules convey important network connectivity and signaling information for normal circadian function, but PDF and insulin-like peptides can also convey signals that lead to apoptosis, enhanced neurodegeneration and cognitive decline in flies carrying circadian mutations or in a senescent state.

  20. Evaluation of heart rhythm variability and arrhythmia in children with systemic and localized scleroderma.

    Science.gov (United States)

    Wozniak, Jacek; Dabrowski, Rafal; Luczak, Dariusz; Kwiatkowska, Malgorzata; Musiej-Nowakowska, Elzbieta; Kowalik, Ilona; Szwed, Hanna

    2009-01-01

    To evaluate possible disturbances in autonomic regulation and cardiac arrhythmias in children with localized and systemic scleroderma. There were 40 children included in the study: 20 with systemic and 20 with localized scleroderma. The control group comprised 20 healthy children. In 24-hour Holter recording, the average rate of sinus rhythm was significantly higher in the groups with systemic and localized scleroderma than in the control group, but there was no significant difference between them. The variability of heart rhythm in both groups was significantly decreased. In the group with systemic scleroderma, single supraventricular ectopic beats were observed in 20% and runs were seen in 40% of patients. In the group with localized scleroderma, supraventricular single ectopic beats occurred in 35% of patients and runs in 45% of those studied. Ventricular arrhythmia occurred in 2 children with systemic scleroderma, but in 1 child, it was complex. The most frequent cardiac arrhythmias in both types of scleroderma in children were of supraventricular origin, whereas ventricular arrhythmias did not occur very often. There were no significant differences in autonomic disturbances manifesting as a higher heart rate and decreased heart rate variability between localized and systemic scleroderma.

  1. [Cardiac rhythm variability as an index of vegetative heart regulation in a situation of psychoemotional tension].

    Science.gov (United States)

    Revina, N E

    2006-01-01

    Differentiated role of segmental and suprasegmental levels of cardiac rhythm variability regulation in dynamics of motivational human conflict was studied for the first time. The author used an original method allowing simultaneous analysis of psychological and physiological parameters of human activity. The study demonstrates that will and anxiety, as components of motivational activity spectrum, form the "energetic" basis of voluntary-constructive and involuntary-affective behavioral strategies, selectively uniting various levels of suprasegmental and segmental control of human heart functioning in a conflict situation.

  2. Burst Activity and Heart Rhythm Modulation in the Sympathetic Outflow to the Heart

    National Research Council Canada - National Science Library

    Baselli, G

    2001-01-01

    In 13 decerebrate, artificially ventilated cats preganglionic sympathetic outflow to the heart was recorded with ECG and ventilation signal, A novel algorithm was implemented that extracts weighted...

  3. Maternal obesity disrupts circadian rhythms of clock and metabolic genes in the offspring heart and liver.

    Science.gov (United States)

    Wang, Danfeng; Chen, Siyu; Liu, Mei; Liu, Chang

    2015-06-01

    Early life nutritional adversity is tightly associated with the development of long-term metabolic disorders. Particularly, maternal obesity and high-fat diets cause high risk of obesity in the offspring. Those offspring are also prone to develop hyperinsulinemia, hepatic steatosis and cardiovascular diseases. However, the precise underlying mechanisms leading to these metabolic dysregulation in the offspring remain unclear. On the other hand, disruptions of diurnal circadian rhythms are known to impair metabolic homeostasis in various tissues including the heart and liver. Therefore, we investigated that whether maternal obesity perturbs the circadian expression rhythms of clock, metabolic and inflammatory genes in offspring heart and liver by using RT-qPCR and Western blotting analysis. Offspring from lean and obese dams were examined on postnatal day 17 and 35, when pups were nursed by their mothers or took food independently. On P17, genes examined in the heart either showed anti-phase oscillations (Cpt1b, Pparα, Per2) or had greater oscillation amplitudes (Bmal1, Tnf-α, Il-6). Such phase abnormalities of these genes were improved on P35, while defects in amplitudes still existed. In the liver of 17-day-old pups exposed to maternal obesity, the oscillation amplitudes of most rhythmic genes examined (except Bmal1) were strongly suppressed. On P35, the oscillations of circadian and inflammatory genes became more robust in the liver, while metabolic genes were still kept non-rhythmic. Maternal obesity also had a profound influence in the protein expression levels of examined genes in offspring heart and liver. Our observations indicate that the circadian clock undergoes nutritional programing, which may contribute to the alternations in energy metabolism associated with the development of metabolic disorders in early life and adulthood.

  4. Routine versus aggressive upstream rhythm control for prevention of early atrial fibrillation in heart failure: background, aims and design of the RACE 3 study.

    Science.gov (United States)

    Alings, M; Smit, M D; Moes, M L; Crijns, H J G M; Tijssen, J G P; Brügemann, J; Hillege, H L; Lane, D A; Lip, G Y H; Smeets, J R L M; Tieleman, R G; Tukkie, R; Willems, F F; Vermond, R A; Van Veldhuisen, D J; Van Gelder, I C

    2013-07-01

    Rhythm control for atrial fibrillation (AF) is cumbersome because of its progressive nature caused by structural remodelling. Upstream therapy refers to therapeutic interventions aiming to modify the atrial substrate, leading to prevention of AF. The Routine versus Aggressive upstream rhythm Control for prevention of Early AF in heart failure (RACE 3) study hypothesises that aggressive upstream rhythm control increases persistence of sinus rhythm compared with conventional rhythm control in patients with early AF and mild-to-moderate early systolic or diastolic heart failure undergoing electrical cardioversion. RACE 3 is a prospective, randomised, open, multinational, multicenter trial. Upstream rhythm control consists of angiotensin converting enzyme inhibitors and/or angiotensin receptor blockers, mineralocorticoid receptor antagonists, statins, cardiac rehabilitation therapy, and intensive counselling on dietary restrictions, exercise maintenance, and drug adherence. Conventional rhythm control consists of routine rhythm control therapy without cardiac rehabilitation therapy and intensive counselling. In both arms, every effort is made to keep patients in the rhythm control strategy, and ion channel antiarrhythmic drugs or pulmonary vein ablation may be instituted if AF relapses. Total inclusion will be 250 patients. If upstream therapy proves to be effective in improving maintenance of sinus rhythm, it could become a new approach to rhythm control supporting conventional pharmacological and non-pharmacological rhythm control.

  5. 2017 consensus of the Asia Pacific Heart Rhythm Society on stroke prevention in atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Chern-En Chiang, MD, PhD

    2017-08-01

    Full Text Available Atrial fibrillation (AF is the most common sustained arrhythmia, causing a 2-fold increase in mortality and a 5-fold increase in stroke. The Asian population is rapidly aging, and in 2050, the estimated population with AF will reach 72 million, of whom 2.9 million may suffer from AF-associated stroke. Therefore, stroke prevention in AF is an urgent issue in Asia. Many innovative advances in the management of AF-associated stroke have emerged recently, including new scoring systems for predicting stroke and bleeding risks, the development of non-vitamin K antagonist oral anticoagulants (NOACs, knowledge of their special benefits in Asians, and new techniques. The Asia Pacific Heart Rhythm Society (APHRS aimed to update the available information, and appointed the Practice Guideline sub-committee to write a consensus statement regarding stroke prevention in AF. The Practice Guidelines sub-committee members comprehensively reviewed updated information on stroke prevention in AF, emphasizing data on NOACs from the Asia Pacific region, and summarized them in this 2017 Consensus of the Asia Pacific Heart Rhythm Society on Stroke Prevention in AF. This consensus includes details of the updated recommendations, along with their background and rationale, focusing on data from the Asia Pacific region. We hope this consensus can be a practical tool for cardiologists, neurologists, geriatricians, and general practitioners in this region. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician׳s decision remains the most important factor in the management of AF.

  6. Pharmacokinetic-pharmacodynamic modeling of QRS-prolongation by flecainide: heart rate-dependent effects during sinus rhythm in conscious telemetered dogs.

    Science.gov (United States)

    Sällström, Johan; Al-Saffar, Ahmad; Pehrson, Rikard

    2014-01-01

    The duration of the QRS interval is determined by the ion currents involved in cardiac depolarization. Class I antiarrhythmic drugs reduce cardiac excitability and conduction by inhibiting Nav1.5 channels responsible for I(Na), thus increasing the QRS interval. Previous studies in humans as well as in animal models have demonstrated a more pronounced effect on QRS-prolongation during higher heart rates. In the present study, the effects of the Nav1.5 inhibitor flecainide on cardiovascular parameters, were studied in the telemetered beagle dog under normal autonomic control. The heart rate dependency of QRS prolongation was characterized using pharmacokinetic-pharmacodynamic (PKPD) modeling. Four male telemetered beagle dogs were administered placebo or flecainide (100, 150 and 200 mg) in a Latin square design. The QRS interval and heart rate were recorded, and blood samples were taken. Plasma concentrations of flecainide were fitted to a one compartment oral model and the intrapolated plasma concentrations were fitted to QRS and heart rate data sampled during 5 h after dosing. Flecainide increased the QRS interval in all dogs, whereas there were no effects on heart rate. Using the PKPD model, a statistically significant heart rate-dependent QRS prolongation was linked to individual concentration-time profiles of flecainide. PKPD analysis of QRS interval data from unrestrained dogs with sinus rhythm can elucidate mechanisms previously only described during controlled heart rhythm. Specific questions can therefore be addressed in generically designed cardiovascular telemetry safety studies and different types of relationships between parameters can be uncovered. In addition, the present approach can be used to better characterize drug-induced QRS effects in cardiovascular dog models. © 2013.

  7. Normal position and malposition of the heart

    International Nuclear Information System (INIS)

    Andresen, J.H.; Eggert Hansen, T.

    1980-01-01

    The main types of heart positions and the malpositions are described as demonstrated on plain films of the thorax. Special attention is drawn to the situs ambiguous with the poly- or asplenia which may be recognized from hypoarterial or epiarterial position of the main bronchi and their equal lengths and courses. This diagnosis is important because of the frequent accompanying congenital cardiac malformations and in respect to the planning of angiocardiography. (orig.) [de

  8. Radiographic heart-volume estimation in normal cats

    International Nuclear Information System (INIS)

    Ahlberg, N.E.; Hansson, K.; Svensson, L.; Iwarsson, K.

    1989-01-01

    Heart volume mensuration was evaluated on conventional radiographs from eight normal cats in different body positions using computed tomography (CT). Heart volumes were calculated from orthogonal thoracic radiographs in ventral and dorsal recumbency and from radiographs exposed with a vertical X-ray beam in dorsal and lateral recumbency using the formula for an ellipsoid body. Heart volumes were also estimated with CT in ventral, dorsal, right lateral and left lateral recumbency. No differences between heart volumes from CT in ventral recumbency and those from CT in right and left lateral recumbency were seen. In dorsal recumbency, however, significantly lower heart volumes were obtained. Heart volumes from CT in ventral recumbency were similar to those from radiographs in ventral and dorsal recumbency and dorsal/left lateral recumbency. Close correlation was also demonstrated between heart volumes from radiographs in dorsal/ left lateral recumbency and body weights of the eight cats

  9. COMPARATIVE EFFECTS OF MONOTHERAPY WITH MAGNESIUM AND COMBINED THERAPY WITH MAGNESIUM AND Β-BLOCKER ON PRIMARY MITRAL VALVE PROLAPSE WITH HEART RHYTHM DISORDERS

    Directory of Open Access Journals (Sweden)

    E. G. Nurtdinova

    2007-01-01

    Full Text Available Aim. To compare effects of monotherapy with magnesium and combined therapy with magnesium and β-blocker on primary mitral valve prolapse (MVP with heart rhythm disorders.Material and methods. 71 patients with primary MVP 1-2 degree and heart rhythm disorders were involved in the study. The patients were split into three groups. Group I (25 persons received monotherapy with magnesium orotate at a dose of 1-3 g per day; group II (28 persons received combined therapy with magnesium orotate and betaxolol. The control group (18 persons received no therapy. Initially and after 12 weeks of observation all the patients underwent electrocardiography (ECG, ECG-Holter monitoring, echocardiography and autonomic balance assessment by A.M. Vein’s questionnaire.Results. In 12 weeks of treatment groups I and II showed positive dynamics in the MVP manifestations, including significant reduction in severity of the autonomic dysfunction syndrome, ECG positive dynamics, antiarrhythmic effect, decrease in the degree of prolapse, diminution of mitral regurgitation and left auricle volumes. More substantial hemodynamic effects were found in the group of patients who received combination therapy.Conclusion. Combined therapy has proven advantages in comparison with magnesium monotherapy in terms of daily quantity of extrasystoles, reduction in heart rate, decrease in autonomic disfunction and normalization of intracardiac hemodynamics.

  10. COMPARATIVE EFFECTS OF MONOTHERAPY WITH MAGNESIUM AND COMBINED THERAPY WITH MAGNESIUM AND Β-BLOCKER ON PRIMARY MITRAL VALVE PROLAPSE WITH HEART RHYTHM DISORDERS

    Directory of Open Access Journals (Sweden)

    E. G. Nurtdinova

    2015-12-01

    Full Text Available Aim. To compare effects of monotherapy with magnesium and combined therapy with magnesium and β-blocker on primary mitral valve prolapse (MVP with heart rhythm disorders.Material and methods. 71 patients with primary MVP 1-2 degree and heart rhythm disorders were involved in the study. The patients were split into three groups. Group I (25 persons received monotherapy with magnesium orotate at a dose of 1-3 g per day; group II (28 persons received combined therapy with magnesium orotate and betaxolol. The control group (18 persons received no therapy. Initially and after 12 weeks of observation all the patients underwent electrocardiography (ECG, ECG-Holter monitoring, echocardiography and autonomic balance assessment by A.M. Vein’s questionnaire.Results. In 12 weeks of treatment groups I and II showed positive dynamics in the MVP manifestations, including significant reduction in severity of the autonomic dysfunction syndrome, ECG positive dynamics, antiarrhythmic effect, decrease in the degree of prolapse, diminution of mitral regurgitation and left auricle volumes. More substantial hemodynamic effects were found in the group of patients who received combination therapy.Conclusion. Combined therapy has proven advantages in comparison with magnesium monotherapy in terms of daily quantity of extrasystoles, reduction in heart rate, decrease in autonomic disfunction and normalization of intracardiac hemodynamics.

  11. Hypertension and cardiac arrhythmias: a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S; Steffel, Jan; Marín, Francisco; de Oliveira Figueiredo, Márcio Jansen; de Simone, Giovanni; Tzou, Wendy S; Chiang, Chern-En; Williams, Bryan; Dan, Gheorghe-Andrei; Gorenek, Bulent; Fauchier, Laurent; Savelieva, Irina; Hatala, Robert; van Gelder, Isabelle; Brguljan-Hitij, Jana; Erdine, Serap; Lovic, Dragan; Kim, Young-Hoon; Salinas-Arce, Jorge; Field, Michael

    2017-06-01

    Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in hypertensive patients, especially in those with left ventricular hypertrophy (LVH) or HF. Also, some of the antihypertensive drugs commonly used to reduce blood pressure, such as thiazide diuretics, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesemia), further contributing to arrhythmias, whereas effective control of blood pressure may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between hypertension and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit to comprehensively review the available evidence to publish a joint consensus document on hypertension and cardiac arrhythmias, and to provide up-to-date consensus recommendations for use in clinical practice. The ultimate judgment regarding care of a particular patient must be made by the healthcare provider and the patient in light of all of the circumstances presented by that patient. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

  12. The effect of the number of consecutive night shifts on diurnal rhythms in cortisol, melatonin and heart rate variability (HRV)

    DEFF Research Database (Denmark)

    Jensen, Marie Aarrebo; Garde, Anne Helene; Kristiansen, Jesper

    2016-01-01

    PURPOSE: The purpose of this review is to summarize the current knowledge from field studies on how many consecutive night shifts are required for adaptation of diurnal rhythms in cortisol, melatonin and heart rate variability (HRV) to night work. METHODS: A systematic search of the databases Pub...... recordings for HRV. Most of the studies in the review were small studies with less than 30 participants, and most studies evaluated diurnal rhythms after only two consecutive night shifts whereas only six studies used seven or more consecutive night shifts. The majority of studies found that adaptation...... to night work had not occurred after two consecutive night shifts, whereas a small number found evidence for full adaptation after seven consecutive night shifts based on diurnal rhythms in cortisol and melatonin. CONCLUSION: There are methodological differences in the field studies analyzing diurnal...

  13. Heart Rhythm Monitoring in the Constellation Lunar and Launch/Landing EVA Suit: Recommendations from an Expert Panel

    Science.gov (United States)

    Scheuring, Richard A.; Hamilton, Doug; Jones, Jeffrey A.; Alexander, David

    2009-01-01

    There are currently several physiological monitoring requirements for EVA in the Human-Systems Interface Requirements (HSIR) document. There are questions as to whether the capability to monitor heart rhythm in the lunar surface space suit is a necessary capability for lunar surface operations. Similarly, there are questions as to whether the capability to monitor heart rhythm during a cabin depressurization scenario in the launch/landing space suit is necessary. This presentation seeks to inform space medicine personnel of recommendations made by an expert panel of cardiovascular medicine specialists regarding in-suit ECG heart rhythm monitoring requirements during lunar surface operations. After a review of demographic information and clinical cases and panel discussion, the panel recommended that ECG monitoring capability as a clinical tool was not essential in the lunar space suit; ECG monitoring was not essential in the launch/landing space suit for contingency scenarios; the current hear rate monitoring capability requirement for both launch/landing and lunar space suits should be maintained; lunar vehicles should be required to have ECG monitoring capability with a minimum of 5-lead ECG for IVA medical assessments; and, exercise stress testing for astronaut selection and retention should be changed from the current 85% maximum heart rate limit to maximal, exhaustive 'symptom-limited' testing to maximize diagnostic utility as a screening tool for evaluating the functional capacity of astronauts and their cardiovascular health.

  14. Antithrombotic therapy in atrial fibrillation associated with valvular heart disease: a joint consensus document from the European Heart Rhythm Association (EHRA) and European Society of Cardiology Working Group on Thrombosis, endorsed by the ESC Working Group on Valvular Heart Disease, Cardiac Arrhythmia Society of Southern Africa (CASSA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Collet, Jean Philippe; Caterina, Raffaele de; Fauchier, Laurent; Lane, Deirdre A; Larsen, Torben B; Marin, Francisco; Morais, Joao; Narasimhan, Calambur; Olshansky, Brian; Pierard, Luc; Potpara, Tatjana; Sarrafzadegan, Nizal; Sliwa, Karen; Varela, Gonzalo; Vilahur, Gemma; Weiss, Thomas; Boriani, Giuseppe; Rocca, Bianca

    2017-11-01

    Atrial fibrillation (AF) is a major worldwide public health problem, and AF in association with valvular heart disease (VHD) is also common. However, management strategies for this group of patients have been less informed by randomized trials, which have largely focused on 'non-valvular AF' patients. Thrombo-embolic risk also varies according to valve lesion and may also be associated with CHA2DS2VASc score risk factor components, rather than only the valve disease being causal. Given marked heterogeneity in the definition of valvular and non-valvular AF and variable management strategies, including non-vitamin K antagonist oral anticoagulants (NOACs) in patients with VHD other than prosthetic heart valves or haemodynamically significant mitral valve disease, there is a need to provide expert recommendations for professionals participating in the care of patients presenting with AF and associated VHD. To address this topic, a Task Force was convened by the European Heart Rhythm Association (EHRA) and European Society of Cardiology (ESC) Working Group on Thrombosis, with representation from the ESC Working Group on Valvular Heart Disease, Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE) with the remit to comprehensively review the published evidence, and to publish a joint consensus document on the management of patients with AF and associated VHD, with up-to-date consensus recommendations for clinical practice for different forms of VHD. This consensus document proposes that the term 'valvular AF' is outdated and given that any definition ultimately relates to the evaluated practical use of oral anticoagulation (OAC) type, we propose a functional Evaluated Heartvalves, Rheumatic or Artificial (EHRA) categorization in relation to the type of OAC use in patients with AF, as follows: (i) EHRA Type 1 VHD, which refers

  15. [Cognitive emotion regulation of patients qualified for implantation of heart rhythm control device].

    Science.gov (United States)

    Ziętalewicz, Urszula; Jędrzejczyk, Jan; Mojkowski, Włodzimierz; Mojkowski, Dariusz

    2016-11-25

    The aim of the artificial heart stimulation is not only saving lives, but also improvement of the quality of life of patients with cardiac arrhythmias. One of the key dimensions of quality of life is psychological functioning. Until now, little research assess this dimension in patients before the implantation of the heart rhythm control device. The aim of the study was to assess the severity of depression and anxiety and the frequency of the used cognitive emotion regulation strategies and to examine the relationship between them. The study group consisted of 60 people qualified for pacemaker implantation (42 PM patients and 18 ICD): 15 women and 45 men ranging in age from 43 to 85. To assess cognitive emotion regulation strategies Cognitive Emotion Regulation Questionnaire was used, and to assess the severity of depression and anxiety - Mood Assessment Questionnaire. Patients with PM more often than patients with ICD use the strategy of Positive Reappraisal (U = 231.50, p = 0.045). There were no statistically significant differences in the frequency of use of other strategies and severity of depression and anxiety. In PM patients there are negative correlations between the severity of depression and anxiety and the use of Acceptance ( τ = -0.380), a Positive Reappraisal ( τ = -0.278), Positive Refocusing ( τ = -0.366) and between the level of anxiety and Putting into Perspective ( τ = -0.402). In ICD patients there was a positive relationship between anxiety and Cathastrophizing ( τ = 0.324). The severity of depression and anxiety, and emotion regulation strategies in patients qualified for PM implantation in comparison with patients qualified for ICD implantation are similar. Both groups of patients show a good adaptation of the psychological.

  16. Use of digoxin and risk of death or readmission for heart failure and sinus rhythm

    DEFF Research Database (Denmark)

    Madelaire, Christian; Schou, Morten; Nelveg-Kristensen, Karl Emil

    2016-01-01

    BACKGROUND/OBJECTIVES: Digoxin is widely used as symptomatic treatment in heart failure (HF), but the role in contemporary treatment of HF with sinus rhythm (SR) is debatable. We investigated the risk of death and hospital readmission, according to digoxin use, in a nationwide cohort of digoxin...... to primary outcomes of all-cause mortality and HF readmission. RESULTS: The study population comprised 5327 digoxin users and 10,654 matched non-users with a median age of 77. During follow-up 10,643 (66.6%) patients died and 7584 (47.5%) patients were readmitted due to HF. Use of digoxin was associated...... with increased risk of death (hazard ratio (HR): 1.19, 95%-CI: 1.15-1.24) and increased risk of HF readmission (HR: 1.19, 95%-CI: 1.13-1.25). Cumulative incidences of readmission, considering death as a competing risk was 50% for digoxin users and 47% for non-users. The associations applied regardless...

  17. Biological rhythm in 1/f fluctuations of heart rate in asthmatic children

    Directory of Open Access Journals (Sweden)

    Norio Kazuma

    2004-01-01

    Conclusion: During an asthma attack, the rhythm of 1/f fluctuations is ultradian (cycle length under 20 h, compared with various rhythms during a non-attack period. In future, we will clarify the relevance of the ultradian rhythm of 1/f fluctuations over a 24 h period and the biological life-support system at a point of time of an asthma attack.

  18. Hypertension and cardiac arrhythmias: executive summary of a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S; Steffel, Jan; Marín, Francisco; de Oliveira Figueiredo, Márcio Jansen; de Simone, Giovanni; Tzou, Wendy S; En Chiang, Chern; Williams, Bryan

    2017-10-01

    Hypertension (HTN) is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease (CAD), stroke, peripheral artery disease and chronic renal failure. Hypertensive heart disease can manifest as many types of cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in HTN patients, especially in those with left ventricular hypertrophy (LVH), CAD, or HF. In addition, high doses of thiazide diuretics commonly used to treat HTN, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesaemia), contributing further to arrhythmias, while effective blood pressure control may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between HTN and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit of comprehensively reviewing the available evidence and publishing a joint consensus document on HTN and cardiac arrhythmias, and providing up-to-date consensus recommendations for use in clinical practice. The ultimate judgment on the care of a specific patient must be made by the healthcare provider and the patient in light of all individual factors presented. This is an executive summary of the full document co-published by EHRA in EP-Europace. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

  19. Diurnal rhythm in serum levels of inhibin B in normal men

    DEFF Research Database (Denmark)

    Carlsen, E; Olsson, C; Petersen, J H

    1999-01-01

    in the early morning hours and lower values in the late afternoon and evening. We did not find evidence for a role of FSH in this diurnal variation of inhibin B. However, covariation with serum levels of testosterone and estradiol suggested that these hormones might play a role in the diurnal rhythm of inhibin...

  20. 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.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  2. 2010 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Training Standards and Maintenance of Competency in Adult Clinical Cardiac Electrophysiology.

    Science.gov (United States)

    Green, Martin S; Guerra, Peter G; Krahn, Andrew D

    2011-01-01

    The last guidelines on training for adult cardiac electrophysiology (EP) were published by the Canadian Cardiovascular Society in 1996. Since then, substantial changes in the knowledge and practice of EP have mandated a review of the previous guidelines by the Canadian Heart Rhythm Society, an affiliate of the Canadian Cardiovascular Society. Novel tools and techniques also now allow electrophysiologists to map and ablate increasingly complex arrhythmias previously managed with pharmacologic or device therapy. Furthermore, no formal attempt had previously been made to standardize EP training across the country. The 2010 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Training Standards and Maintenance of Competency in Adult Clinical Cardiac Electrophysiology represent a consensus arrived at by panel members from both societies, as well as EP program directors across Canada and other select contributors. In describing program requirements, the technical and cognitive skills that must be acquired to meet training standards, as well as the minimum number of procedures needed in order to acquire these skills, the new guidelines provide EP program directors and committee members with a template to develop an appropriate curriculum for EP training for cardiology fellows here in Canada. Copyright © 2011 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  3. Independent component analysis of normal and abnormal rhythm in twin pregnancies

    International Nuclear Information System (INIS)

    Mensah-Brown, Nana Aba; Lutter, William J; Wakai, Ronald T; Comani, Silvia; Strasburger, Janette F

    2011-01-01

    We investigated the utility of ICA for evaluation of fetal rhythm in five uncomplicated twin pregnancies and in five twin pregnancies complicated by fetal arrhythmia. Using objective and subjective criteria, we sought to determine how the signal-to-noise ratio, signal fidelity and interference rejection are affected when synthesizing the fetal signal using all the signal-containing ICA components (rank-p ICA) versus using the single dominant component (rank-1 ICA). The signal of each fetus was most commonly distributed over 1 or 2 ICA components, as previously observed in studies of singleton pregnancies; however, in 8 of 26 (31%) cases the signal of each fetus was distributed over 3, 4 or even 5 ICA components. Rank-1 ICA provided the highest SNR and interference rejection, but at the cost of reduced signal fidelity. Our results corroborate that in twin pregnancies, including twin pregnancies complicated by fetal arrhythmia, rank-1 ICA is very effective in isolating the QRS complexes of each fetus; however, it has some limitations when used for fetal rhythm evaluation due to signal distortion. Occasionally, rank-1 ICA completely separates the P-wave and the T-wave from the QRS complex, thus requiring the mixing of several ICA components to achieve acceptable signal fidelity

  4. Extracorporeal Cardiopulmonary Resuscitation Among Patients with Structurally Normal Hearts.

    Science.gov (United States)

    Conrad, Stephanie J; Bridges, Brian C; Kalra, Yuvraj; Pietsch, John B; Smith, Andrew H

    Extracorporeal cardiopulmonary resuscitation (eCPR) has been well described as a rescue therapy in refractory cardiac arrest among patients with congenital heart disease. The purpose of this retrospective analysis of data from the Extracorporeal Life Support Organization was to evaluate outcomes of eCPR in patients with structurally normal hearts and to identify risk factors that may contribute to mortality. During the study period, 1,431 patients met inclusion criteria. Median age was 16 years. Overall survival to hospital discharge was 32%. Conditional logistic regression demonstrated an independent survival benefit among smaller patients, patients with a lower partial pressure of carbon dioxide (PaCO2) on cannulation, and those with a shorter duration from intubation to eCPR cannulation. A diagnosis of sepsis was independently associated with a nearly threefold increase in odds of mortality, whereas the diagnosis of myocarditis portended a more favorable outcome. Neurologic complications, pulmonary hemorrhage, disseminated intravascular coagulation, CPR, pH less than 7.20, and hyperbilirubinemia after eCPR cannulation were independently associated with an increase in odds of mortality. When utilizing eCPR in patients with structurally normal hearts, a diagnosis of sepsis is independently associated with mortality, whereas a diagnosis of myocarditis is protective. Neurologic complications and pulmonary hemorrhage while on extracorporeal membrane oxygenation (ECMO) are independently associated with mortality.

  5. Circadian rhythms of cysteine proteinases and cystatins, potential tumour markers, in normal sera

    International Nuclear Information System (INIS)

    Cimerman, N.; Krasovec, M.; Mesko-Brguljan, P.; Suskovic, S.; Kos, J.

    2002-01-01

    Circadian day/night variations have been evidenced in all major groups of organisms and at all levels of organisation of the organism. Circadian intra-individual variations are known for a number of analyses in serum including tumour-associated markers. It was suggested that the serum levels of cysteine proteinases and their inhibitors may be of clinical importance for prognosis and diagnosis in cancer. Since known circadian rhythms are important for choosing the best sampling time, interpretation of the results of a diagnostic test, patient monitoring, and timing of a therapy, our objective was to establish 24-h variations of cysteine proteinases, cathepsins B, H, L, and their low molecular weight inhibitors, stefin A, stefin B, and cystatin C, in sera from healthy subjects. (author)

  6. Effects of simulated microgravity on circadian rhythm of caudal arterial pressure and heart rate in rats and their underlying mechanism

    Directory of Open Access Journals (Sweden)

    Li CHEN

    2016-04-01

    Full Text Available Objective  To explore the effects of simulated microgravity on the circadian rhythm of rats' caudal arterial pressure and heart rate, and their underlying mechanism. Methods  Eighteen male SD rats (aged 8 weeks were randomly assigned to control (CON and tail suspension (SUS group (9 each. Rats with tail suspension for 28 days were adopted as the animal model to simulate microgravity. Caudal arterial pressure and heart rate of rats were measured every 3 hours. The circadian difference of abdominal aorta contraction was measured by aortic ring test. Western blotting was performed to determine and compare the protein expression level of clock genes such as Per2 (Period2, Bmal1 (Aryl hydrocarbon receptor nuclear translocatorlike and dbp (D element binding protein in suprachiasmatic nucleus (SCN and abdominal aorta of rats in CON and SUS group at different time points. Results  Compared with CON group, the caudal arterial pressure, both systolic and diastolic pressure, decreased significantly and the diurnal variability disappeared, meanwhile the heart rate increased obviously and also the diurnal variability disappeared in rats of SUS group. Compared with CON group, the contraction reactivity of abdominal aorta decreased with disappearence of the diurnal variability, and also the clock genes expression in SCN and abdominal aorta showed no diurnal variability in rats of SUS group. Conclusion  Simulated microgravity may lead to circadian rhythm disorders in rats' cardiovascular system, which may be associated with the changes of the clock genes expression. DOI: 10.11855/j.issn.0577-7402.2016.04.06

  7. Image quality and radiation dose of single heartbeat 640-slice coronary CT angiography: A comparison between patients with chronic Atrial Fibrillation and subjects in normal sinus rhythm by propensity analysis

    International Nuclear Information System (INIS)

    Di Cesare, Ernesto; Gennarelli, Antonio; Di Sibio, Alessandra; Felli, Valentina; Splendiani, Alessandra; Gravina, Giovanni Luca; Masciocchi, Carlo

    2015-01-01

    Highlights: •Atrial Fibrillation (AF) may affect CCTA image quality. •We compare the results of single heartbeat CCTA in subjects with chronic AF and in sinus rhythm. •Single heartbeat CCTA may be feasible also in subjects with cAF and HR <72 bpm. •In cAF patients with heart rate higher than 72 bpm, CCTA has more movement-associated artefacts. •Mean effective dose of single heartbeat CCTA in cAF group was higher than in sinus rhythm one. -- Abstract: Objectives: To evaluate image quality and radiation dose of single heartbeat 640-slice coronary CT angiography (CCTA) in patients with chronic Atrial Fibrillation (cAF) in comparison with subjects in normal sinus rhythm. Methods: A cohort of 71 patients with cAF was matched with 71 subjects in normal sinus rhythm (NSR) and HR ≤ 65 bpm using a matched by propensity analysis. All subjects underwent a single heartbeat CCTA with prospective gating. In subjects with cAF, we manually established the acquisition of data only from a single heartbeat. Mean effective dose and image quality, with both objective and subjective measures, were assessed. Results: 96.4% of all segments in the cAF group had diagnostic image quality. The rate of subjects with at least one non-diagnostic segment was 14% and 2.8% (p = 0.031) in the cAF and NRS groups, respectively. In the cAF group, the percentage of patients with at least one non-diagnostic segment for acquisition HR ≤ 72 was 1.8% (1/55), and it did not significantly differ from the NSR group (2.8%; 2/71) (p = 1.0). Objective quality parameters did not show a statistically significant difference between the two groups. The mean effective dose was 4.24 ± 1.24 mSv in the cAF group and 2.67 ± 0.5 mSv in the sinus rhythm group (p < 0.0001) with an increase by 59% in the cAF group with respect to the SNR group. Conclusions: A single heartbeat acquisition protocol with a 640-slice prospectively ECG-triggered CT angiography may be feasible in patients with cAF and HR below 72

  8. Image quality and radiation dose of single heartbeat 640-slice coronary CT angiography: A comparison between patients with chronic Atrial Fibrillation and subjects in normal sinus rhythm by propensity analysis

    Energy Technology Data Exchange (ETDEWEB)

    Di Cesare, Ernesto, E-mail: ernesto.dicesare@cc.univaq.it [Department of Biotechnological and Applied Clinical Sciences, Division of Radiotherapy, Laboratory of Radiobiology, University of L’Aquila (Italy); Gennarelli, Antonio; Di Sibio, Alessandra; Felli, Valentina; Splendiani, Alessandra [Department of Biotechnological and Applied Clinical Sciences, Division of Radiology, Laboratory of Radiobiology, University of L’Aquila (Italy); Gravina, Giovanni Luca [Department of Biotechnological and Applied Clinical Sciences, Division of Radiotherapy, Laboratory of Radiobiology, University of L’Aquila (Italy); Masciocchi, Carlo [Department of Biotechnological and Applied Clinical Sciences, Division of Radiology, Laboratory of Radiobiology, University of L’Aquila (Italy)

    2015-04-15

    Highlights: •Atrial Fibrillation (AF) may affect CCTA image quality. •We compare the results of single heartbeat CCTA in subjects with chronic AF and in sinus rhythm. •Single heartbeat CCTA may be feasible also in subjects with cAF and HR <72 bpm. •In cAF patients with heart rate higher than 72 bpm, CCTA has more movement-associated artefacts. •Mean effective dose of single heartbeat CCTA in cAF group was higher than in sinus rhythm one. -- Abstract: Objectives: To evaluate image quality and radiation dose of single heartbeat 640-slice coronary CT angiography (CCTA) in patients with chronic Atrial Fibrillation (cAF) in comparison with subjects in normal sinus rhythm. Methods: A cohort of 71 patients with cAF was matched with 71 subjects in normal sinus rhythm (NSR) and HR ≤ 65 bpm using a matched by propensity analysis. All subjects underwent a single heartbeat CCTA with prospective gating. In subjects with cAF, we manually established the acquisition of data only from a single heartbeat. Mean effective dose and image quality, with both objective and subjective measures, were assessed. Results: 96.4% of all segments in the cAF group had diagnostic image quality. The rate of subjects with at least one non-diagnostic segment was 14% and 2.8% (p = 0.031) in the cAF and NRS groups, respectively. In the cAF group, the percentage of patients with at least one non-diagnostic segment for acquisition HR ≤ 72 was 1.8% (1/55), and it did not significantly differ from the NSR group (2.8%; 2/71) (p = 1.0). Objective quality parameters did not show a statistically significant difference between the two groups. The mean effective dose was 4.24 ± 1.24 mSv in the cAF group and 2.67 ± 0.5 mSv in the sinus rhythm group (p < 0.0001) with an increase by 59% in the cAF group with respect to the SNR group. Conclusions: A single heartbeat acquisition protocol with a 640-slice prospectively ECG-triggered CT angiography may be feasible in patients with cAF and HR below 72

  9. Normal and abnormal electrical activation of the heart. Imaging patterns obtained by phase analysis of equilibrium cardiac studies

    International Nuclear Information System (INIS)

    Pavel, D.; Byrom, E.; Swiryn, S.; Meyer-Pavel, C.; Rosen, K.

    1981-01-01

    By using a temporal Fourier analysis of gated equilibrium cardiac studies, phase images were obtained. These functional images were analysed qualitatively and quantitatively to determine if specific patterns can be found for normal versus abnormal electrical activation of the heart. The study included eight subjects with normal cardiac function and 24 patients with abnormal electrical activation: eight with left bundle branch block (LBBB), two with right bundle branch block (RBBB), six with Wolff-Parkinson-White syndrome (WPW), one with junctional rhythm, one with spontaneous sustained ventricular tachycardia (VT) (all with normal wall motion), two with chronic transvenous pacemakers, and four with induced sustained VT (all with regional wall motion abnormalities). The results show that the two ventricals have the same mean phase (within +-9 0 ) in normals, but significantly different mean phases in all patients with bundle branch blocks. Of the six WPW patients, three had a distinctive abnormal pattern. The patient with junctional rhythm, those with transvenous pacemakers, and those with VT all had abnormal patterns on the phase image. The phase image is capable of showing differences between patients with electrical activation and a variety of electrical abnormalities. Within the latter category distinct patterns can be associated with each type of abnormality. (author)

  10. Ecstasy (MDMA) Alters Cardiac Gene Expression and DNA Methylation: Implications for Circadian Rhythm Dysfunction in the Heart.

    Science.gov (United States)

    Koczor, Christopher A; Ludlow, Ivan; Hight, Robert S; Jiao, Zhe; Fields, Earl; Ludaway, Tomika; Russ, Rodney; Torres, Rebecca A; Lewis, William

    2015-11-01

    MDMA (ecstasy) is an illicit drug that stimulates monoamine neurotransmitter release and inhibits reuptake. MDMA's acute cardiotoxicity includes tachycardia and arrhythmia which are associated with cardiomyopathy. MDMA acute cardiotoxicity has been explored, but neither long-term MDMA cardiac pathological changes nor epigenetic changes have been evaluated. Microarray analyses were employed to identify cardiac gene expression changes and epigenetic DNA methylation changes. To identify permanent MDMA-induced pathogenetic changes, mice received daily 10- or 35-day MDMA, or daily 10-day MDMA followed by 25-day saline washout (10 + 25 days). MDMA treatment caused differential gene expression (p 1.5) in 752 genes following 10 days, 558 genes following 35 days, and 113 genes following 10-day MDMA + 25-day saline washout. Changes in MAPK and circadian rhythm gene expression were identified as early as 10 days. After 35 days, circadian rhythm genes (Per3, CLOCK, ARNTL, and NPAS2) persisted to be differentially expressed. MDMA caused DNA hypermethylation and hypomethylation that was independent of gene expression; hypermethylation of genes was found to be 71% at 10 days, 68% at 35 days, and 91% at 10 + 25 days washout. Differential gene expression paralleled DNA methylation in 22% of genes at 10-day treatment, 17% at 35 days, and 48% at 10 + 25 days washout. We show here that MDMA induced cardiac epigenetic changes in DNA methylation where hypermethylation predominated. Moreover, MDMA induced gene expression of key elements of circadian rhythm regulatory genes. This suggests a fundamental organism-level event to explain some of the etiologies of MDMA dysfunction in the heart. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

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

    OpenAIRE

    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

    2013-01-01

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

  12. Distinct Thalamic Reticular Cell Types Differentially Modulate Normal and Pathological Cortical Rhythms

    Directory of Open Access Journals (Sweden)

    Alexandra Clemente-Perez

    2017-06-01

    Full Text Available Integrative brain functions depend on widely distributed, rhythmically coordinated computations. Through its long-ranging connections with cortex and most senses, the thalamus orchestrates the flow of cognitive and sensory information. Essential in this process, the nucleus reticularis thalami (nRT gates different information streams through its extensive inhibition onto other thalamic nuclei, however, we lack an understanding of how different inhibitory neuron subpopulations in nRT function as gatekeepers. We dissociated the connectivity, physiology, and circuit functions of neurons within rodent nRT, based on parvalbumin (PV and somatostatin (SOM expression, and validated the existence of such populations in human nRT. We found that PV, but not SOM, cells are rhythmogenic, and that PV and SOM neurons are connected to and modulate distinct thalamocortical circuits. Notably, PV, but not SOM, neurons modulate somatosensory behavior and disrupt seizures. These results provide a conceptual framework for how nRT may gate incoming information to modulate brain-wide rhythms.

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

    NARCIS (Netherlands)

    den Hoed, M.A.H.; Eijgelsheim, M.; Esko, T.; Brundel, B.J.; Peal, D.S.; Evans, D.M.; Nolte, I.M.; Segrè, A.V.; Holm, H.; Handsaker, R.E.; Westra, H.J.; Johnson, T.; Isaacs, A.; Yang, L.; Lundby, A.; Zhao, J.H.; Kim, Y.J.; Go, M.J.; Almgren, P.; Bochud, M.; Boucher, G.; Cornelis, M.C.; Gudbjartsson, D.F.; Hadley, D.; van der Harst, P.; Hayward, C.; den Heijer, M.; Igl, W.; Jackson, A.U.; Kutalik, Z.; Luan, J.; Kemp, J.P.; Kristiansson, K.; Ladenvall, C.; Lorentzon, M.; Montasser, M.E.; Njajou, O.T.; O'Reilly, P.F.; Padmanabhan, S.; St Pourcain, B.; Rankinen, T.; Salo, P.; Tanaka, T.; Timpson, N.J.; Vitart, V.; Waite, L.; Wheeler, W.; Zhang, W.; Draisma, H.H.M.; Feitosa, M.F.; Kerr, K.F.; Lind, P.A.; Mihailov, E.; Onland-Moret, N.C.; Song, C.; Weedon, M.N.; Xie, W.; Yengo, L.; Absher, D.; Albert, C.M.; Alonso, A.; Arking, D.E.; de Bakker, P.I.; Balkau, B.; Barlassina, C.; Benaglio, P.; Bis, J.C.; Bouatia-Naji, N.; Brage, S.; Chanock, S.J.; Chines, P.S.; Chung, M.; Darbar, D.; Dina, C.; Dörr, M.; Elliott, P.; Felix, S.B.; Fischer, K.; Fuchsberger, C.; de Geus, E.J.C.; Goyette, P.; Gudnason, V.; Harris, T.B.; Hartikainen, A.L.; Havulinna, A.S.; Heckbert, S.R.; Hicks, A.A.; Hofman, A.; Holewijn, S.; Hoogstra-Berends, F.; Hottenga, J.J.; Jensen, M.K.; Johansson, A.; Junttila, J.; Kääb, S.; Kanon, B.; Ketkar, S.; Khaw, K.T.; Knowles, J.W.; Kooner, A.S.; Kors, J.A.; Kumari, M.; Milani, L.; Laiho, P.; Lakatta, E.G.; Langenberg, C.; Leusink, M.; Liu, Y.; Luben, R.N.; Lunetta, K.L.; Lynch, S.N.; Markus, M.R.; Marques-Vidal, P.; Mateo Leach, I.; McArdle, W.L.; McCarroll, S.A.; Medland, S.E.; Miller, K.A.; Montgomery, G.W.; Morrison, A.C.; Müller-Nurasyid, M.; Navarro, P.; Nelis, M.; O'Connell, J.R.; O'Donnell, C.J.; Ong, K.K.; Newman, A.B.; Peters, A.; Polasek, O.; Pouta, A.; Pramstaller, P.P.; Psaty, B.M.; Rao, D.C.; Ring, S.M.; Rossin, E.J.; Rudan, D.; Sanna, S.; Scott, R.A.; Sehmi, J.S.; Sharp, S.; Shin, J.T.; Singleton, A.B.; Smith, A.V.; Soranzo, N.; Spector, T.D.; Stewart, C.; Stringham, H.M.; Tarasov, K.V.; Uitterlinden, A.G.; Vandenput, L.; Hwang, S.J.; Whitfield, J.B.; Wijmenga, C.; Wild, S.H.; Willemsen, G.; Wilson, J.F.; Witteman, J.C.; Wong, A.; Wong, Q.; Jamshidi, Y.; Zitting, P.; Boer, J.M.; Boomsma, D.I.; Borecki, I.B.; van Duijn, C.M.; Ekelund, U.; Forouhi, N.G.; Froguel, P.; Hingorani, A.D.; Ingelsson, E.; Kivimaki, M.; Kronmal, R.A.; Kuh, D; Lind, L.; Martin, N.G.; Oostra, B.A.; Pedersen, N.L.; Quertermous, T.; Rotter, J.I.; van der Schouw, Y.T.; Verschuren, W.M.; Walker, M.; Albanes, D.; Arnar, D.O.; Assimes, T.L.; Bandinelli, S.; Boehnke, M.; de Boer, R.A.; Bouchard, C.; Caulfield, W.L.; Chambers, J.C.; Curhan, G.; Cusi, D.; Eriksson, J.; Ferrucci, L.; van Gilst, W.H.; Glorioso, N.; de Graaf, J.; Groop, L.; Gyllensten, U.; Hsueh, W.C.; Hu, F.B.; Huikuri, H.V.; Hunter, D.J.; Iribarren, C.; Isomaa, B.; Järvelin, M.R.; Jula, A.; Kähönen, M.; Kiemeney, L.A.; van der Klauw, M.M.; Kooner, J.S.; Kraft, P.; Iacoviello, L.; Lehtimäki, T.; Lokki, M.L.; Mitchell, B.D.; Navis, G.; Nieminen, M.S.; Ohlsson, C.; Poulter, N.R.; Qi, L.; Raitakari, O.T.; Rimm, E.B.; Rioux, J.D.; Rizzi, F.; Rudan, I.; Salomaa, V.; Sever, P.S.; Shields, D.C.; Shuldiner, A.R.; Sinisalo, J.; Stanton, A.V.; Stolk, R.P.; Strachan, D.P.; Tardif, J.C.; Thorsteinsdottir, U.; Tuomilehto, J.; van Veldhuisen, D.J.; Virtamo, J.; Viikari, J.; Vollenweider, P.; Waeber, G.; Widen, E.; Cho, Y.S.; Olsen, J.V.; Visscher, P.M.; Willer, C.J.; Franke, L; Erdmann, J.; Thompson, J.R.; Pfeufer, A.; Sotoodehnia, N.; Newton-Cheh, C.; Ellinor, P.T.; Stricker, B.H.C.; Metspalu, A.; Perola, M.; Beckmann, J.S.; Smith, G.D.; Stefansson, K.; Wareham, N.J.; Munroe, P.B.; Sibon, O.C.M.; Milan, D.J.; Snieder, H.; Samani, N.J.; Loos, R.J.

    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

  14. Circadian rhythms in the incidence of apoptotic cells and number of clonogenic cells in intestinal crypts after radiation using normal and reversed light conditions

    International Nuclear Information System (INIS)

    Ijiri, K.; Potten, C.S.

    1988-01-01

    Variations in the number of radiation-induced morphologically dead or dying cells (apoptotic cells) in the crypts in the small intestine of the mouse have been studied throughout a 24-h period under a normal light regimen. A clear circadian rhythm was displayed in the apoptotic incidence 3 or 6 h after irradiation for each gamma-ray dose studied (range 0.14-9.0 Gy). The most prominent circadian rhythm was obtained after 0.5 Gy. Peak time of day for inducing apoptosis was 06.00-09.00 h, and the trough occurred at 18.00-21.00 h. Some mice were also transferred to a reversed light cycle, and irradiated on different days after transfer. Apoptosis induced by 0.5 Gy or 9.0 Gy, or number of surviving crypts (microcolonies) after 11.0 Gy or 13.0 Gy was examined. The transition point for reversal of circadian rhythm in apoptosis (after 0.5 Gy) occurred 7 days after transfer and the rhythm was reversed by 14 days. The rhythm for crypt survival (i.e. for clonogenic cell radiosensitivity) was disturbed on 1 day and transition point for reversal occurred 3 days after transfer. The rhythm became reversed by 7 days. (author)

  15. Evidence for disruption of normal circadian cortisol rhythm in women with obesity.

    Science.gov (United States)

    Al-Safi, Zain A; Polotsky, Alex; Chosich, Justin; Roth, Lauren; Allshouse, Amanda A; Bradford, Andrew P; Santoro, Nanette

    2018-04-01

    Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis may play a role in the pathogenesis of comorbidities encountered in obesity, including the relative hypogonadotropic hypogonadism that we and others have observed. We sought to examine serum cortisol profiles throughout the day and evening in a sample of normal weight women and women with obesity. In this cross-sectional study, regularly cycling obese (n = 12) and normal weight (n = 10) women were recruited. Mean serum cortisol was measured by frequent blood sampling for 16 h (8am-midnight) in the luteal phase of the menstrual cycle. Women with obesity had significantly higher overall cortisol levels when compared to normal weight women (6.2 [4.3, 6.6] vs. 4.7 [3.7, 5.5] ug/dl, p = .04). Over the two-hour postprandial period, obese women displayed an almost two-fold greater (7.2 [6.5, 8.6] ug/dl) rise in cortisol than normal weight controls (4.4 [3.7, 6.2] ug/dl, p obese women demonstrated a sustained evening cortisol elevation compared to normal weight women, who displayed the typical decline in cortisol (3.2 [2.3, 4] vs. 2 [1.5, 3.2] ug/dl, p obesity may be related to risks of obesity-associated metabolic comorbidities and reproductive dysfunction often seen in these women.

  16. Plasma melatonin circadian rhythms during the menstrual cycle and after light therapy in premenstrual dysphoric disorder and normal control subjects.

    Science.gov (United States)

    Parry, B L; Berga, S L; Mostofi, N; Klauber, M R; Resnick, A

    1997-02-01

    The aim of this study was to replicate and extend previous work in which the authors observed lower, shorter, and advanced nocturnal melatonin secretion patterns in premenstrually depressed patients compared to those in healthy control women. The authors also sought to test the hypothesis that the therapeutic effect of bright light in patients was associated with corrective effects on the phase, duration, and amplitude of melatonin rhythms. In 21 subjects with premenstrual dysphoric disorder (PMDD) and 11 normal control (NC) subjects, the authors measured the circadian profile of melatonin during follicular and luteal menstrual cycle phases and after 1 week of light therapy administered daily, in a randomized crossover design. During three separate luteal phases, the treatments were either (1) bright (> 2,500 lux) white morning (AM; 06:30 to 08:30 h), (2) bright white evening (PM; 19:00 to 21:00 h), or (3) dim (compressed, and area under the curve, amplitude, and mean levels were decreased. In NC subjects, melatonin rhythms did not change significantly during the menstrual cycle. After AM light in PMDD subjects, onset and offset times were advanced and both duration and midpoint concentration were decreased as compared to RED light. After PM light in PMDD subjects, onset and offset times were delayed, midpoint concentration was increased, and duration was decreased as compared to RED light. By contrast, after light therapy in NC subjects, duration did not change; onset, offset, and midpoint concentration changed as they did in PMDD subjects. When the magnitude of advance and delay phase shifts in onset versus offset time with AM, PM, or RED light were compared, the authors found that in PMDD subjects light shifted offset time more than onset time and that AM light had a greater effect on shifting melatonin offset time (measured the following night in RED light), whereas PM light had a greater effect in shifting melatonin onset time. These findings replicate the

  17. Normal Values for Heart Electrophysiology Parameters of Healthy Swine Determined on Electrophysiology Study.

    Science.gov (United States)

    Noszczyk-Nowak, Agnieszka; Cepiel, Alicja; Janiszewski, Adrian; Pasławski, Robert; Gajek, Jacek; Pasławska, Urszula; Nicpoń, Józef

    2016-01-01

    Swine are a well-recognized animal model for human cardiovascular diseases. Despite the widespread use of porcine model in experimental electrophysiology, still no reference values for intracardiac electrical activity and conduction parameters determined during an invasive electrophysiology study (EPS) have been developed in this species thus far. The aim of the study was to develop a set of normal values for intracardiac electrical activity and conduction parameters determined during an invasive EPS of swine. The study included 36 healthy domestic swine (24-40 kg body weight). EPS was performed under a general anesthesia with midazolam, propofol and isoflurane. The reference values for intracardiac electrical activity and conduction parameters were calculated as arithmetic means ± 2 standard deviations. The reference values were determined for AH, HV and PA intervals, interatrial conduction time at its own and imposed rhythm, sinus node recovery time (SNRT), corrected sinus node recovery time (CSNRT), anterograde and retrograde Wenckebach points, atrial, atrioventricular node and ventricular refractory periods. No significant correlations were found between body weight and heart rate of the examined pigs and their electrophysiological parameters. The hereby presented reference values can be helpful in comparing the results of various studies, as well as in more accurately estimating the values of electrophysiological parameters that can be expected in a given experiment.

  18. Heart rhythm at the time of death documented by an implantable loop recorder

    DEFF Research Database (Denmark)

    Gang, Uffe Jakob Ortved; Jøns, Christian; Jørgensen, Rikke Mørch

    2009-01-01

    Aims The aims of this study were to describe arrhythmias documented with an implantable loop recorder (ILR) in post-acute myocardial infarction (AMI) patients with left ventricular dysfunction at the time of death and to establish the correlation to mode of death. Methods and results Post......-mortem ILR device interrogations were analysed from patients dying in the CARISMA study. Mode of death was classified by a modified CAST classification. Twenty-six patients died with an implanted ILR. Of these, 16 had an electrocardiogram recorded at the time of death. Ventricular tachycardia (VT......)/ventricular fibrillation (VF) was terminal rhythm in eight patients and bradyarrhythmias were observed in another eight patients. Of the deaths with peri-mortem recordings, seven were classified as sudden cardiac death (SCD). In six of these, VF was documented at the time of death. Six monitored deaths were classified...

  19. Safety of sports participation in patients with implantable cardioverter defibrillators: a survey of heart rhythm society members.

    Science.gov (United States)

    Lampert, Rachel; Cannom, David; Olshansky, Brian

    2006-01-01

    Safety of Sports for ICD Patients. The safety of sports participation for patients with implantable cardioverter defibrillators (ICDs) is unknown, and recommendations among physicians may vary widely. The purposes of this study were to determine current practice among patients with ICDs and their physicians regarding sports participation, and to determine how many physicians have cared for patients who have sustained adverse events during sports participation. A survey was mailed to all 1,687 U.S. physician members of the Heart Rhythm Society. Among 614 respondent physicians, recommendations varied widely. Only 10% recommended avoidance of all sports more vigorous than golf. Seventy-six percent recommended avoidance of contact, and 45% recommend avoidance of competitive sports. Most (71%) based restrictions on patients' underlying heart disease. Regardless of recommendations, most physicians (71%) reported caring for patients who participated in sports, including many citing vigorous, competitive sports, most commonly cited were basketball, running, and skiing. ICD shocks during sports were common, cited by 40% of physicians. However, few adverse consequences were reported. One percent of physicians reported known injury to patient (all but 3 minor); 5%, injury to the ICD system, and weightlifting and golf. Physician recommendations for sports participation for patients with ICDs varies widely. Many patients with ICDs do participate in vigorous and even competitive sports. While shocks were common, significant adverse events were rare.

  20. Detection of heart rate and rhythm with a smartphone-based electrocardiograph versus a reference standard electrocardiograph in dogs and cats.

    Science.gov (United States)

    Kraus, Marc S; Gelzer, Anna R; Rishniw, Mark

    2016-07-15

    OBJECTIVE To evaluate the diagnostic utility of ECGs acquired with a smartphone-based device, compared with reference 6-lead ECGs, for identification of heart rate and rhythm in dogs and cats. DESIGN Prospective study. ANIMALS 51 client-owned dogs and 27 client-owned cats. PROCEDURES Patients examined by a small animal referral cardiology service between April 2012 and January 2013 were enrolled consecutively. In each patient, a 30-second ECG was simultaneously acquired with a smartphone-based device (a bipolar, single-lead recorder coupled to a smartphone with an ECG application) and a standard 6-lead ECG machine. Recordings were evaluated by 3 board-certified cardiologists, and intra- and interobserver agreement were evaluated for both rhythm diagnosis and QRS polarity identification. RESULTS Values for instantaneous and mean heart rates for the smartphone-acquired and reference ECGs were within 1 beat of each other when mean heart rates were calculated. Intraobserver agreement for rhythm assessment was very high, with maximum disagreement for any observer for only 2 of 51 dogs and only 4 of 27 cats. There was minimal disagreement in the polarity of depolarization between the smartphone-acquired and reference ECGs in dogs but frequent disagreement in cats. Interobserver agreement for smartphone-acquired ECGs was similar to that for reference ECGs. with all 3 observers agreeing on the rhythm analysis and minimal disagreement on polarity. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that ECGs acquired with the smartphone-based device accurately identified heart rate and rhythm in dogs and cats. Thus, the device may allow veterinarians to evaluate and manage cardiac arrhythmias relatively inexpensively at the cage side and could also allow clinicians to rapidly share information via email for further consultation, potentially enhancing patient care.

  1. [Variability of heart rhythm in dynamic study of the psychovegetative relationship in neurogenic syncope].

    Science.gov (United States)

    Musaeva, Z A; Khaspekova, N B; Veĭn, A M

    2001-01-01

    Physiological changes accompanying syncopes of neural origin (SNO) in patients with psychovegetative syndrome are still insufficiently studied. The data concerning the role of the autonomic nervous system are discrepant. Heart rate variability was analyzed in 68 patients with SNO in a supine position and during the active 20-min orthostatic test taking into account the heart rate components of very low frequency (VLF, an index of cerebral sympathetic activity) and high frequency (HF, a marker of vagal modulation). Steady growth of the VLF and progressive decrease in the LF within 15-20 min of the orthostasis were observed in all the patients (n = 33), who fainted after this period. The predominance of the VLF in the heart rate power spectra was correlated with a high level of anxiety. It is suggested that this fact indicates the stable cerebral sympathetic activation resulting in a baroreceptor dysfunction, i.e., a failure of vasomotor regulation in patients with SNO.

  2. Normal cardiac diameters in cine-MRI of the heart

    International Nuclear Information System (INIS)

    Hergan, K.; Schuster, A.; Mair, M.; Burger, R.; Toepker, M.

    2004-01-01

    Purpose: To measure the normal diameters of cardiac cavities in standard cardiac views using cine MRI. Materials and Methods: Fifty-six volunteers were examined (27 male, 29 female) on a 1.5 T MR unit with ECG-triggered single shot free precision (SSFP) cine MR sequences and parallel image acquisition. Standardized echocardiographic planes were used to depict the heart of all volunteers (short axis, 4-chamber view, left and right 2-chamber views). The different diameters of the cardiac cavities were measured using a fixed protocol. Results: For the estimation of ventricular dilatation, the important female/male cross diameters of the left ventricle are 45.2±3.4/51.6±4.6 mm diastolic and 30.5±3.5/33.8±3.6 mm systolic, and of the right ventricle 30.7±3.8/37.1±5.9 mm diastolic and 22.3±3.8/28.1±4.4 mm systolic. For the determination of a left ventricular hypertrophy, relevant septal wall thickness measured in the short axis of the left ventricle of female/male volunteers are 8.0±1.0/9.9±1.2 mm diastolic and 10.9±1.4/13.6±1.9 mm systolic. The measured normal values of male volunteers were generally higher than those of female volunteers. The thickness of the ventricular septum correlated well when measured in the short axis and 4-chamber view. When measured in the 4-chamber view, the longitudinal diameter of the ventricles had a higher value in diastole and a lower value in systole, compared to the 2-chamber views of the right and left cardiac cavities. The atrial longitudinal diameters were higher in the 4-chamber view compared to the 2-chamber views, without any difference in systole or diastole. Conclusion: Diameters of cardiac cavities are easily and quickly measured. Using the tables with the normal values published here, it is simple to estimate an abnormal size of the heart. (orig.)

  3. Advances in heart rate variability signal analysis: joint position statement by the e-Cardiology ESC Working Group and the European Heart Rhythm Association co-endorsed by the Asia Pacific Heart Rhythm Society.

    Science.gov (United States)

    Sassi, Roberto; Cerutti, Sergio; Lombardi, Federico; Malik, Marek; Huikuri, Heikki V; Peng, Chung-Kang; Schmidt, Georg; Yamamoto, Yoshiharu

    2015-09-01

    Following the publication of the Task Force document on heart rate variability (HRV) in 1996, a number of articles have been published to describe new HRV methodologies and their application in different physiological and clinical studies. This document presents a critical review of the new methods. A particular attention has been paid to methodologies that have not been reported in the 1996 standardization document but have been more recently tested in sufficiently sized populations. The following methods were considered: Long-range correlation and fractal analysis; Short-term complexity; Entropy and regularity; and Nonlinear dynamical systems and chaotic behaviour. For each of these methods, technical aspects, clinical achievements, and suggestions for clinical application were reviewed. While the novel approaches have contributed in the technical understanding of the signal character of HRV, their success in developing new clinical tools, such as those for the identification of high-risk patients, has been rather limited. Available results obtained in selected populations of patients by specialized laboratories are nevertheless of interest but new prospective studies are needed. The investigation of new parameters, descriptive of the complex regulation mechanisms of heart rate, has to be encouraged because not all information in the HRV signal is captured by traditional methods. The new technologies thus could provide after proper validation, additional physiological, and clinical meaning. Multidisciplinary dialogue and specialized courses in the combination of clinical cardiology and complex signal processing methods seem warranted for further advances in studies of cardiac oscillations and in the understanding normal and abnormal cardiac control processes. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  4. An exploration of heart rate response to differing music rhythm and tempos.

    Science.gov (United States)

    da Silva, Ariany G; Guida, Heraldo L; Antônio, Ana Márcia Dos S; Marcomini, Renata S; Fontes, Anne M G G; Carlos de Abreu, Luiz; Roque, Adriano L; Silva, Sidney B; Raimundo, Rodrigo D; Ferreira, Celso; Valenti, Vitor E

    2014-05-01

    The aim of this study was to investigate acute cardiac response and heart rate variability (HRV) when listening to differing forms of music. Eleven healthy men aged between 18 and 25 years old were included in the study. HRV was recorded at rest for ten minutes with no music, then were asked to listen to classical baroque or heavy metal music for a period of 20 min. It was noted that heart rate variability did not affect HRV indices for time and frequency. In conclusion, music with different tempos does not influence cardiac autonomic regulation in men. However more studies are suggested to explore this topic in greater detail. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  5. Effects of electromagnetic radiation (bright light, extremely low-frequency magnetic fields, infrared radiation) on the circadian rhythm of melatonin synthesis, rectal temperature, and heart rate.

    Science.gov (United States)

    Griefahn, Barbara; Künemund, Christa; Blaszkewicz, Meinolf; Lerchl, Alexander; Degen, Gisela H

    2002-10-01

    Electromagnetic spectra reduce melatonin production and delay the nadirs of rectal temperature and heart rate. Seven healthy men (16-22 yrs) completed 4 permuted sessions. The control session consisted of a 24-hours bedrest at infrared radiation (65 degrees C) was applied from 5 pm to 1 am. Salivary melatonin level was determined hourly, rectal temperature and heart rate were continuously recorded. Melatonin synthesis was completely suppressed by light but resumed thereafter. The nadirs of rectal temperature and heart rate were delayed. The magnetic field had no effect. Infrared radiation elevated rectal temperature and heart rate. Only bright light affected the circadian rhythms of melatonin synthesis, rectal temperature, and heart rate, however, differently thus causing a dissociation, which might enhance the adverse effects of shiftwork in the long run.

  6. Normal radiographic heart volume in the neonate. Pt. 3

    International Nuclear Information System (INIS)

    Dahlstroem, A.; Ringertz, H.G.; Sachsska Pediatric Hospital, Stockholm

    1985-01-01

    The diagnostic power of the heart volume and the cardiothoracic ratio in congenital heart disease in neonates has been compared. A consecutive series of 130 children with suspection of heart disease examined radiologically at between 48 h and 15 days of age were followed for 14+-10 months. Of these, 16 (12%) were diagnosed as having congenital heart disease. The number of false positive and negative diagnoses was less for heart volume than for cardiothoracic ratio using +2 SD as limit for pathology. Accuracy, sensitivity and specificity was 84, 75, and 85% respectively for heart volume and 73, 57, and 75% for cardiothoracic ratio. Cases that were false positive with both methods were significantly more often examined between 48 and 72 hours of age indicating that the explanation might be a somewhat late closure of the ductus arteriosus. (orig.)

  7. Daily rhythms of blood pressure, heart rate, and body temperature in fed and fasted male dogs.

    Science.gov (United States)

    Piccione, G; Caola, G; Refinetti, R

    2005-10-01

    Daily or circadian rhythmicity in physiological processes has been described in a large number of species of birds and mammals. However, in dogs, most studies have either failed to detect rhythmicity or have found that rhythmicity reflects merely an acute exogenous effect of feeding rather than an autonomous rhythmic process. In the present study, we investigated the rhythmicity of body temperature, blood pressure, and heart rate in dogs fed daily as well as in dogs deprived of food for 60 h. Our results document clear rhythmicity in all three parameters and demonstrate that the rhythmicity is independent of the feeding schedule. The failure of various previous investigations to document daily rhythmicity in dogs is probably due to lack of experimental rigour rather than to weakness of daily rhythmicity in dogs.

  8. [Behavior of circadian rhythm of ACTH and cortisol in 16 normal subjects after a balanced normocaloric diet and after a high protein diet (Cosinor mean method)].

    Science.gov (United States)

    Sellini, M; Giovannini, C; Manzo, G; Barletta, C; Borboni, P

    1983-01-31

    In 16 normal subjects the circadian rhythm of ACTH has been studied during normal calories diet and after a 15 days period of high protein content diet (2 g/Kg body weight). The statistical study, according Cosinor method, has shown a significant increase of the mesor and of the amplitude, but has not shown any change of the ACTH and Cortisol rhythm, after hyperproteic diet. Data advise the increase of the tonic and fasic secretion of both hormones and shown the mantained acrophase. The action of the protein on the ACTH and Cortisol secretion does not seem related to mechanism like stress, neither to the probable mediation of intestinal like-ACTH messengers. On the contrary it seems related to a direct stimulus on the diencephalo-pituitary axis; it is possible that some amino-acids (tryptophan, arginine) act as a mediator, even if data concern just the effect of the over mentioned amino-acid in large doses.

  9. Antithrombotic Therapy in Atrial Fibrillation Associated with Valvular Heart Disease: Executive Summary of a Joint Consensus Document from the European Heart Rhythm Association (EHRA) and European Society of Cardiology Working Group on Thrombosis, Endorsed by the ESC Working Group on Valvular Heart Disease, Cardiac Arrhythmia Society of Southern Africa (CASSA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

    Science.gov (United States)

    Lip, Gregory Y H; Collet, Jean Philippe; de Caterina, Raffaele; Fauchier, Laurent; Lane, Deirdre A; Larsen, Torben B; Marin, Francisco; Morais, Joao; Narasimhan, Calambur; Olshansky, Brian; Pierard, Luc; Potpara, Tatjana; Sarrafzadegan, Nizal; Sliwa, Karen; Varela, Gonzalo; Vilahur, Gemma; Weiss, Thomas; Boriani, Giuseppe; Rocca, Bianca

    2017-12-01

    Management strategies for patients with atrial fibrillation (AF) in association with valvular heart disease (VHD) have been less informed by randomized trials, which have largely focused on ‘non-valvular AF’ patients. Thromboembolic risk also varies according to valve lesion and may also be associated with CHA2DS2-VASc score risk factor components, rather than only the valve disease being causal. Given the need to provide expert recommendations for professionals participating in the care of patients presenting with AF and associated VHD, a task force was convened by the European Heart Rhythm Association (EHRA) and European Society of Cardiology (ESC) Working Group (WG) on Thrombosis, with representation from the ESC WG on Valvular Heart Disease, Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE) with the remit to comprehensively review the published evidence, and to produce a consensus document on the management of patients with AF and associated VHD, with up-to-date consensus statements for clinical practice for different forms of VHD, based on the principles of evidence-based medicine. This is an executive summary of a consensus document which proposes that the term ‘valvular AF’ is outdated and given that any definition ultimately relates to the evaluated practical use of oral anticoagulation (OAC) type, we propose a functional EHRA (Evaluated Heartvalves, Rheumatic or Artificial) categorization in relation to the type of OAC use in patients with AF, as follows: (1) EHRA (Evaluated Heartvalves, Rheumatic or Artificial) type 1 VHD, which refers to AF patients with ‘VHD needing therapy with a vitamin K antagonist (VKA)’ and (2) EHRA (Evaluated Heartvalves, Rheumatic or Artificial) type 2 VHD, which refers to AF patients with ‘VHD needing therapy with a VKA or a non-VKA oral anticoagulant also taking

  10. Energetic Interrelationship between Spontaneous Low-Frequency Fluctuations in Regional Cerebral Blood Volume, Arterial Blood Pressure, Heart Rate, and Respiratory Rhythm

    Science.gov (United States)

    Katura, Takusige; Yagyu, Akihiko; Obata, Akiko; Yamazaki, Kyoko; Maki, Atsushi; Abe, Masanori; Tanaka, Naoki

    2007-07-01

    Strong spontaneous fluctuations around 0.1 and 0.3 Hz have been observed in blood-related brain-function measurements such as functional magnetic resonance imaging and optical topography (or functional near-infrared spectroscopy). These fluctuations seem to reflect the interaction between the cerebral circulation system and the systemic circulation system. We took an energetic viewpoint in our analysis of the interrelationships between fluctuations in cerebral blood volume (CBV), mean arterial blood pressure (MAP), heart rate (HR), and respiratory rhythm based on multivariate autoregressive modeling. This approach involves evaluating the contribution of each fluctuation or rhythm to specific ones by performing multivariate spectral analysis. The results we obtained show MAP and HR can account slightly for the fluctuation around 0.1 Hz in CBV, while the fluctuation around 0.3 Hz is derived mainly from the respiratory rhythm. During our presentation, we will report on the effects of posture on the interrelationship between the fluctuations and the respiratory rhythm.

  11. Updated European Heart Rhythm Association practical guide on the use of non-vitamin-K antagonist anticoagulants in patients with non-valvular atrial fibrillation: Executive summary.

    Science.gov (United States)

    Heidbuchel, Hein; Verhamme, Peter; Alings, Marco; Antz, Matthias; Diener, Hans-Christoph; Hacke, Werner; Oldgren, Jonas; Sinnaeve, Peter; Camm, A John; Kirchhof, Paulus

    2017-07-14

    In 2013, the European Heart Rhythm Association (EHRA) published a Practical Guide on the use of non-VKA oral anticoagulants (NOACs) in patients with atrial fibrillation (AF) (Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, Sinnaeve P, Camm AJ, Kirchhof P, European Heart Rhythm A. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-651; Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, Sinnaeve P, Camm AJ, Kirchhof P. EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary. Eur Heart J 2013;34:2094-2106). The document received widespread interest, not only from cardiologists but also from neurologists, geriatricians, and general practitioners, as became evident from the distribution of >350 000 copies of its pocket version (the EHRA Key Message Booklet) world-wide. Since 2013, numerous new studies have appeared on different aspects of NOAC therapy in AF patients. Therefore, EHRA updated the Practical Guide, including new information but also providing balanced guiding in the many areas where prospective data are still lacking. The outline of the original guide that addressed 15 clinical scenarios has been preserved, but all chapters have been rewritten. Main changes in the Update comprise a discussion on the definition of 'non-valvular AF' and eligibility for NOAC therapy, inclusion of finalized information on the recently approved edoxaban, tailored dosing information dependent on concomitant drugs, and/or clinical characteristics, an expanded chapter on neurologic scenarios (ischaemic stroke or intracranial haemorrhage under NOAC), an updated anticoagulation card and more specifics on start-up and follow-up issues. There are also many new flow charts, like on appropriate switching between anticoagulants (VKA to NOAC or vice versa), default scenarios for

  12. Impact of heart rate in atrial fibrillation versus sinus rhythm on mortality in octogenarian patients with acute coronary syndrome.

    Science.gov (United States)

    Li, Shijun; Barywani, Salim; Fu, Michael

    2017-01-01

    Association of heart rate (HR) with mortality in patients with acute coronary syndrome (ACS) and aged ≥ 80 years are underrepresented in clinical trials. We therefore aimed to investigate the association of HR in atrial fibrillation (AF) versus sinus rhythm (SR) with all-cause mortality in octogenarian patients with ACS. A total of 336 patients with ACS patients and aged ≥ 80 years were enrolled into the current study. The end point of interest was death from any cause. Association of HR in AF versus SR with mortality was analyzed by Kaplan-Meier curve following log-rank test and multivariable Cox regression analysis. In total, 63 (87.5%) of patients with AF were dead and 147 (59.8%) of patients with SR were dead during the follow-up period. The best cut-off was 80 bpm, with a sensitivity of 62% and specificity of 66%. HR ≤ 80 bpm in SR but not in AF was associated with better outcome as compared with HR > 80 bpm (Chi-Square = 26.55, Log rank P < 0.001). In SR subgroup, the hazard ratios of HR ≤ 80 bpm were 0.51(95% CI 0.37-0.70, P < 0.001) adjusted for age, 0.46 (95%CI 0.33-0.63, P < 0.001) adjusted for gender, 0.62 (95%CI 0.42- 0.93, P = 0.020) adjusted for multivariables respectively. In AF subgroup, the hazard ratios of HR ≤ 80 bpm were 0.83(95% CI 0.49-1.38, P = 0.464) adjusted for age, 0.96 (95%CI 0.59-1.58, P = 0.882) adjusted for gender, 0.72(95% CI 0.41-1.26, P = 0.249) adjusted for multivariables respectively. The current study demonstrates that heart rate is an independent prognostic predictor for all-cause mortality, and HR ≤ 80 bpm is associated with improved outcome in SR but not in AF in octogenarian patients with ACS.

  13. Formation of a national network for rapid response to device and lead advisories: The Canadian Heart Rhythm Society Device Advisory Committee

    Science.gov (United States)

    Krahn, Andrew D; Simpson, Christopher S; Parkash, Ratika; Yee, Raymond; Champagne, Jean; Healey, Jeffrey S; Cameron, Doug; Thibault, Bernard; Mangat, Iqwal; Tung, Stanley; Sterns, Laurence; Birnie, David H; Exner, Derek V; Sivakumaran, Soori; Davies, Ted; Coutu, Benoit; Crystal, Eugene; Wolfe, Kevin; Verma, Atul; Stephenson, Elizabeth A; Sanatani, Shubhayan; Gow, Robert; Connors, Sean; Paredes, Felix Ayala; Turabian, Mike; Kus, Teresa; Essebag, Vidal; Gardner, Martin

    2009-01-01

    The Canadian Heart Rhythm Society (CHRS) Device Advisory Committee was commissioned to respond to advisories regarding cardiac rhythm device and lead performance on behalf of the CHRS. In the event of an advisory, the Chair uses an e-mail network to disseminate advisory information to Committee members broadly representative of the Canadian device community. A consensus recommendation is prepared by the Committee and made available to all Canadian centres on the CHRS Web site after approval by the CHRS executive. This collaborative approach using an e-mail network has proven very efficient in providing a rapid national response to device advisories. The network is an ideal tool to collect specific data on implanted device system performance and allows for prompt reporting of clinically relevant data to front-line clinicians and patients. PMID:19584969

  14. Early Embryonic Heart Rate in Normal Pregnancies In Memory of ...

    African Journals Online (AJOL)

    To determine the appearance and development of embryonic heart rate a total of n = 317 Nigerian pregnant women were studied in the very early pregnancy from 23 – 56 days from the onset of last menstrual period (LMP). All pregnancies had a subsequent successful outcome. Transvaginal ultrasonography was ...

  15. Activity, sleep and ambient light have a different impact on circadian blood pressure, heart rate and body temperature rhythms.

    Science.gov (United States)

    Gubin, D G; Weinert, D; Rybina, S V; Danilova, L A; Solovieva, S V; Durov, A M; Prokopiev, N Y; Ushakov, P A

    2017-01-01

    The aim of the present study was to investigate the impact of endogenous and exogenous factors for the expression of the daily rhythms of body temperature (BT), blood pressure (BP) and heart rate (HR). One hundred and seventy-three young adults (YA), 17-24 years old (y.o.), of both genders were studied under a modified constant-routine (CR) protocol for 26 h. Participants were assigned randomly to groups with different lighting regimens: CR-LD, n = 77, lights (>400 l×) on from 09:00 to 17:00 h and off (lights on (>400 l×) during the whole experimental session; CR-DD, n = 15, constant dim light (Blood Pressure Monitoring (ABPM) records from 27 YA (16-38 y.o.) and BT self-measurement data from 70 YA (17-30 y.o.) taken on ≥ 3 successive days at 08:00, 11:00, 14:00, 17:00, 20:00, 23:00 and 03:00 were available. The obtained daily patterns were different between Control and CR-DD groups, due to effects of activity, sleep and light. The comparison of Control and CR-LD groups allowed the effects of sleep and activity to be estimated since the lighting conditions were similar. The activity level substantially elevated SBP, but not DBP. Sleep, on the other hand, lowered the nighttime DBP, but has no effect on SBP. HR was affected both by activity and sleep. In accordance with previous studies, these results confirm that the steep BP increase in the morning is not driven by the circadian clock, but rather by sympathoadrenal factors related to awakening and corresponding anticipatory mechanisms. The effect on BT was not significant. To investigate the impact of light during the former dark time and darkness during the former light time, the CR-LL and CR-DD groups were each compared with the CR-LD group. Light delayed the evening decrease of BT, most likely via a suppression of the melatonin rise. Besides, it had a prominent arousal effect on SBP both in the former light and dark phases, a moderate effect on DBP and no effect on HR. Darkness induced decline in BT. BP

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  17. Standard heart and vessel size on plain films of normal children

    International Nuclear Information System (INIS)

    Stoever, B.

    1986-01-01

    Standards of heart size, i.e. heart diameters and heart volume of normal children aged 4-15 years were obtained. In all cases requiring exact heart size determination, heart volume calculation is mandatory in children as well as in adults. Statistical work to date has provided precise calculation of heart volume plain films in the upright position. Additional plain films in prone position are unnecessary because no evident orthostatic influence on heart volume in children can be found. Percentiles of normal heart volume related to body weight representing the best correlation to the individual data are given as well as percentiles related to age. Furthermore ratios of normal vessel size to the height of the 8sup(th) thoracic vertebral body, measured on the same plain film, are given. In addition the ratio of upper to lower lung vessel size is calculated. These ratios are useful criteria in estimating normal vessel size and also in cases with increased pulmonary venous pressure. (orig.) [de

  18. Cardioprotective effects of SGLT2 inhibitors are possibly associated with normalization of the circadian rhythm of blood pressure.

    Science.gov (United States)

    Rahman, Asadur; Hitomi, Hirofumi; Nishiyama, Akira

    2017-06-01

    Improvement in cardiovascular (CV) morbidity and mortality in the EMPA-REG OUTCOME study provides new insight into the therapeutic use of sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors in patients with type 2 diabetes. Although SGLT2 inhibitors have several pleiotropic effects, the underlying mechanism responsible for their cardioprotective effects remains undetermined. In this regard, the absence of a nocturnal fall in blood pressure (BP), that is, non-dipping BP, is a common phenomenon in type 2 diabetes and has a crucial role in the pathogenesis of CV morbidity and mortality. In most clinical trials, SGLT2 inhibitors reduce both systolic BP (~3-5 mm Hg) and diastolic BP (~2 mm Hg) in patients with type 2 diabetes. In addition, recent clinical and animal studies have revealed that SGLT2 inhibitors enable the change in BP circadian rhythm from a non-dipper to a dipper type, which is possibly associated with the improvement in CV outcomes in patients with type 2 diabetes. In this review, recent data on the effect of SGLT2 inhibitors on the circadian rhythm of BP will be summarized. The possible underlying mechanisms responsible for the SGLT2 inhibitor-induced improvement in the circadian rhythm of BP will also be discussed.

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

    OpenAIRE

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

    2017-01-01

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

  20. A New MRI-Based Model of Heart Function with Coupled Hemodynamics and Application to Normal and Diseased Canine Left Ventricles

    Science.gov (United States)

    Choi, Young Joon; Constantino, Jason; Vedula, Vijay; Trayanova, Natalia; Mittal, Rajat

    2015-01-01

    A methodology for the simulation of heart function that combines an MRI-based model of cardiac electromechanics (CE) with a Navier–Stokes-based hemodynamics model is presented. The CE model consists of two coupled components that simulate the electrical and the mechanical functions of the heart. Accurate representations of ventricular geometry and fiber orientations are constructed from the structural magnetic resonance and the diffusion tensor MR images, respectively. The deformation of the ventricle obtained from the electromechanical model serves as input to the hemodynamics model in this one-way coupled approach via imposed kinematic wall velocity boundary conditions and at the same time, governs the blood flow into and out of the ventricular volume. The time-dependent endocardial surfaces are registered using a diffeomorphic mapping algorithm, while the intraventricular blood flow patterns are simulated using a sharp-interface immersed boundary method-based flow solver. The utility of the combined heart-function model is demonstrated by comparing the hemodynamic characteristics of a normal canine heart beating in sinus rhythm against that of the dyssynchronously beating failing heart. We also discuss the potential of coupled CE and hemodynamics models for various clinical applications. PMID:26442254

  1. Comprehensive risk reduction in patients with atrial fibrillation: emerging diagnostic and therapeutic options--a report from the 3rd Atrial Fibrillation Competence NETwork/European Heart Rhythm Association consensus conference

    DEFF Research Database (Denmark)

    Kirchhof, Paulus; Lip, Gregory Y H; Van Gelder, Isabelle C

    2012-01-01

    While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes...... the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper...

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

    Science.gov (United States)

    Kilit, Celal; Paşalı Kilit, Türkan

    2017-05-01

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

  3. Classification of single normal and Alzheimer’s disease individuals from cortical sources of resting state EEG rhythms

    Directory of Open Access Journals (Sweden)

    Claudio eBabiloni

    2016-02-01

    Full Text Available Previous studies have shown abnormal power and functional connectivity of resting state electroencephalographic (EEG rhythms in groups of Alzheimer’s disease (AD compared to healthy elderly (Nold subjects. Here we tested the best classification rate of 120 AD patients and 100 matched Nold subjects using EEG markers based on cortical sources of power and functional connectivity of these rhythms. EEG data were recorded during resting state eyes-closed condition. Exact low-resolution brain electromagnetic tomography (eLORETA estimated the power and functional connectivity of cortical sources in frontal, central, parietal, occipital, temporal, and limbic regions. Delta (2-4 Hz, theta (4-8 Hz, alpha 1 (8-10.5 Hz, alpha 2 (10.5-13 Hz, beta 1 (13-20 Hz, beta 2 (20-30 Hz, and gamma (30-40 Hz were the frequency bands of interest. The classification rates of interest were those with an area under the receiver operating characteristic curve (AUROC higher than 0.7 as a threshold for a moderate classification rate (i.e. 70%. Results showed that the following EEG markers overcame this threshold: (i central, parietal, occipital, temporal, and limbic delta/alpha 1 current density; (ii central, parietal, occipital temporal, and limbic delta/alpha 2 current density; (iii frontal theta/alpha 1 current density; (iv occipital delta/alpha 1 inter-hemispherical connectivity; (v occipital-temporal theta/alpha 1 right and left intra-hemispherical connectivity; and (vi parietal-limbic alpha 1 right intra-hemispherical connectivity. Occipital delta/alpha 1 current density showed the best classification rate (sensitivity of 73.3%, specificity of 78%, accuracy of 75.5%, and AUROC of 82%. These results suggest that EEG source markers can classify Nold and AD individuals with a moderate classification rate higher than 80%.

  4. Cardiovascular cast model fabrication and casting effectiveness evaluation in fetus with severe congenital heart disease or normal heart.

    Science.gov (United States)

    Wang, Yu; Cao, Hai-yan; Xie, Ming-xing; He, Lin; Han, Wei; Hong, Liu; Peng, Yuan; Hu, Yun-fei; Song, Ben-cai; Wang, Jing; Wang, Bin; Deng, Cheng

    2016-04-01

    To investigate the application and effectiveness of vascular corrosion technique in preparing fetal cardiovascular cast models, 10 normal fetal heart specimens with other congenital disease (control group) and 18 specimens with severe congenital heart disease (case group) from induced abortions were enrolled in this study from March 2013 to June 2015 in our hospital. Cast models were prepared by injecting casting material into vascular lumen to demonstrate real geometries of fetal cardiovascular system. Casting effectiveness was analyzed in terms of local anatomic structures and different anatomical levels (including overall level, atrioventricular and great vascular system, left-sided and right-sided heart), as well as different trimesters of pregnancy. In our study, all specimens were successfully casted. Casting effectiveness analysis of local anatomic structures showed a mean score from 1.90±1.45 to 3.60±0.52, without significant differences between case and control groups in most local anatomic structures except left ventricle, which had a higher score in control group (P=0.027). Inter-group comparison of casting effectiveness in different anatomical levels showed no significant differences between the two groups. Intra-group comparison also revealed undifferentiated casting effectiveness between atrioventricular and great vascular system, or left-sided and right-sided heart in corresponding group. Third-trimester group had a significantly higher perfusion score in great vascular system than second-trimester group (P=0.046), while the other anatomical levels displayed no such difference. Vascular corrosion technique can be successfully used in fabrication of fetal cardiovascular cast model. It is also a reliable method to demonstrate three-dimensional anatomy of severe congenital heart disease and normal heart in fetus.

  5. Hypertension and cardiac arrhythmias : A consensus document fromthe European Heart RhythmAssociation (EHRA) and ESC Council on Hypertension, endorsed by the Heart RhythmSociety (HRS), Asia-Pacific Heart RhythmSociety (APHRS) and Sociedad Latinoamericana de Estimulacion Cardiaca y Electrofisiologia (SOLEACE)

    NARCIS (Netherlands)

    Lip, Gregory Y. H.; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S.; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S.; Steffel, Jan; Marin, Francisco; de Oliveira Figueiredo, Marcio Jansen; de Simone, Giovanni; Tzou, Wendy S.; Chiang, Chern-En; Williams, Bryan; Dan, Gheorghe-Andrei; Gorenek, Bulent; Fauchier, Laurent; Savelieva, Irina; Hatala, Robert; van Gelder, Isabelle; Brguljan-Hitij, Jana; Erdine, Serap; Lovic, Dragan; Kim, Young-Hoon; Salinas-Arce, Jorge; Field, Michael

    2017-01-01

    Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both

  6. THE EFFECT OF WAIST CIRCUMFERENCES MORE THAN NORMAL ON THE INCIDENT OF CORONARY HEART DISEASE

    Directory of Open Access Journals (Sweden)

    Pria Wahyu

    2017-07-01

    Full Text Available Introduction: Coronary heart disease is known as the most common disease that causes mortality in the world, one of the examination to identify the risks of coronary heart disease is measuring waist circumference. The purpose of this study was to identify correlation between large waist circumferences and the incident of coroner heart disease. Method: Design used in this study was analytic observational (retrospective with cross sectional approach. There were 63 respondents which sampling by simple random sampling. The independent variable was waist circumferences and the dependent variable was coronary heart disease. Data were collected by direct observation then analyzed by spearman correlation statistic test with significance level α≤0.05. Result: The result showed that waist circumferences more than normal had significant correlation with the incident of coronary heart disease (p=0.02. Analysis: It can be concluded that there was correlation between waist circumferences more than normal and the incident of coronary heart disease to the clients with coroner cardiac disease. Discussion: Earlier screening and detection is needed to prevent coronary heart disease.

  7. Normalization of NAD+ Redox Balance as a Therapy for Heart Failure.

    Science.gov (United States)

    Lee, Chi Fung; Chavez, Juan D; Garcia-Menendez, Lorena; Choi, Yongseon; Roe, Nathan D; Chiao, Ying Ann; Edgar, John S; Goo, Young Ah; Goodlett, David R; Bruce, James E; Tian, Rong

    2016-09-20

    Impairments of mitochondrial function in the heart are linked intricately to the development of heart failure, but there is no therapy for mitochondrial dysfunction. We assessed the reduced/oxidized ratio of nicotinamide adenine dinucleotide (NADH/NAD(+) ratio) and protein acetylation in the failing heart. Proteome and acetylome analyses were followed by docking calculation, mutagenesis, and mitochondrial calcium uptake assays to determine the functional role of specific acetylation sites. The therapeutic effects of normalizing mitochondrial protein acetylation by expanding the NAD(+) pool also were tested. Increased NADH/NAD(+) and protein hyperacetylation, previously observed in genetic models of defective mitochondrial function, also are present in human failing hearts as well as in mouse hearts with pathologic hypertrophy. Elevation of NAD(+) levels by stimulating the NAD(+) salvage pathway suppressed mitochondrial protein hyperacetylation and cardiac hypertrophy, and improved cardiac function in responses to stresses. Acetylome analysis identified a subpopulation of mitochondrial proteins that was sensitive to changes in the NADH/NAD(+) ratio. Hyperacetylation of mitochondrial malate-aspartate shuttle proteins impaired the transport and oxidation of cytosolic NADH in the mitochondria, resulting in altered cytosolic redox state and energy deficiency. Furthermore, acetylation of oligomycin-sensitive conferring protein at lysine-70 in adenosine triphosphate synthase complex promoted its interaction with cyclophilin D, and sensitized the opening of mitochondrial permeability transition pore. Both could be alleviated by normalizing the NAD(+) redox balance either genetically or pharmacologically. We show that mitochondrial protein hyperacetylation due to NAD(+) redox imbalance contributes to the pathologic remodeling of the heart via 2 distinct mechanisms. Our preclinical data demonstrate a clear benefit of normalizing NADH/NAD(+) imbalance in the failing hearts

  8. Bleeding risk assessment and management in atrial fibrillation patients. Executive Summary of a Position Document from the European Heart Rhythm Association [EHRA], endorsed by the European Society of Cardiology [ESC] Working Group on Thrombosis

    NARCIS (Netherlands)

    Lip, Gregory Y. H.; Andreotti, Felicita; Fauchier, Laurent; Huber, Kurt; Hylek, Elaine; Knight, Eve; Lane, Deirdre; Levi, Marcel; Marín, Francisco; Palareti, Gualtiero; Kirchhof, Paulus

    2011-01-01

    In this executive summary of a Consensus Document from the European Heart Rhythm Association, endorsed by the European Society of Cardiology Working Group on Thrombosis, we comprehensively review the published evidence and propose a consensus on bleeding risk assessments in atrial fibrillation (AF)

  9. 3D imaging of the mitochondrial redox state of rat hearts under normal and fasting conditions

    Directory of Open Access Journals (Sweden)

    He N. Xu

    2014-03-01

    Full Text Available The heart requires continuous ATP availability that is generated in the mitochondria. Although studies using the cell culture and perfused organ models have been carried out to investigate the biochemistry in the mitochondria in response to a change in substrate supply, mitochondrial bioenergetics of heart under normal feed or fasting conditions has not been studied at the tissue level with a sub-millimeter spatial resolution either in vivo or ex vivo. Oxidation of many food-derived metabolites to generate ATP in the mitochondria is realized through the NADH/NAD+ couple acting as a central electron carrier. We employed the Chance redox scanner — the low-temperature fluorescence scanner to image the three-dimensional (3D spatial distribution of the mitochondrial redox states in heart tissues of rats under normal feeding or an overnight starvation for 14.5 h. Multiple consecutive sections of each heart were imaged to map three redox indices, i.e., NADH, oxidized flavoproteins (Fp, including flavin adenine dinucleotide (FAD and the redox ratio NADH/Fp. The imaging results revealed the micro-heterogeneity and the spatial distribution of these redox indices. The quantitative analysis showed that in the fasted hearts the standard deviation of both NADH and Fp, i.e., SD_NADH and SD_Fp, significantly decreased with a p value of 0.032 and 0.045, respectively, indicating that the hearts become relatively more homogeneous after fasting. The fasted hearts contained 28.6% less NADH (p = 0.038. No significant change in Fp was found (p = 0.4. The NADH/Fp ratio decreased with a marginal p value (0.076. The decreased NADH in the fasted hearts is consistent with the cardiac cells' reliance of fatty acids consumption for energy metabolism when glucose becomes scarce. The experimental observation of NADH decrease induced by dietary restriction in the heart at tissue level has not been reported to our best knowledge. The Chance redox scanner demonstrated the

  10. 3D IMAGING OF THE MITOCHONDRIAL REDOX STATE OF RAT HEARTS UNDER NORMAL AND FASTING CONDITIONS.

    Science.gov (United States)

    Xu, He N; Zhou, Rong; Moon, Lily; Feng, Min; Li, Lin Z

    2014-03-01

    The heart requires continuous ATP availability that is generated in the mitochondria. Although studies using the cell culture and perfused organ models have been carried out to investigate the biochemistry in the mitochondria in response to a change in substrate supply, mitochondrial bioenergetics of heart under normal feed or fasting conditions has not been studied at the tissue level with a sub-millimeter spatial resolution either in vivo or ex vivo . Oxidation of many food-derived metabolites to generate ATP in the mitochondria is realized through the NADH/NAD + couple acting as a central electron carrier. We employed the Chance redox scanner - the low-temperature fluorescence scanner to image the three-dimensional (3D) spatial distribution of the mitochondrial redox states in heart tissues of rats under normal feeding or an overnight starvation for 14.5 h. Multiple consecutive sections of each heart were imaged to map three redox indices, i.e., NADH, oxidized flavoproteins (Fp, including flavin adenine dinucleotide (FAD)) and the redox ratio NADH/Fp. The imaging results revealed the micro-heterogeneity and the spatial distribution of these redox indices. The quantitative analysis showed that in the fasted hearts the standard deviation of both NADH and Fp, i.e., SD_NADH and SD_Fp, significantly decreased with a p value of 0.032 and 0.045, respectively, indicating that the hearts become relatively more homogeneous after fasting. The fasted hearts contained 28.6% less NADH ( p = 0.038). No significant change in Fp was found ( p = 0.4). The NADH/Fp ratio decreased with a marginal p value (0.076). The decreased NADH in the fasted hearts is consistent with the cardiac cells' reliance of fatty acids consumption for energy metabolism when glucose becomes scarce. The experimental observation of NADH decrease induced by dietary restriction in the heart at tissue level has not been reported to our best knowledge. The Chance redox scanner demonstrated the feasibility of 3D

  11. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    thus appear to be simple responses of living beings to cyclic presence/absence of ... For example, during leaf movement rhythms, leaves alternate between open and closed states .... gist of his time, in an elegant experiment (Box 2) to study the navigational .... diurnal rhythms as true biological timekeepers, a question which.

  12. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    and clocks driving such rhythms have been studied for a long time now, our ... passage of time using near 24 h oscillation as a reference process, and (iii) Output .... Bünning's work on circadian rhythms across model systems ranging from ..... E Bünning, The Physiological Clock, Revised 3rd Edition, The English. Universities ...

  13. Multivariate Normal Tissue Complication Probability Modeling of Heart Valve Dysfunction in Hodgkin Lymphoma Survivors

    International Nuclear Information System (INIS)

    Cella, Laura; Liuzzi, Raffaele; Conson, Manuel; D’Avino, Vittoria; Salvatore, Marco; Pacelli, Roberto

    2013-01-01

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced asymptomatic heart valvular defects (RVD). Methods and Materials: Fifty-six patients treated with sequential chemoradiation therapy for Hodgkin lymphoma (HL) were retrospectively reviewed for RVD events. Clinical information along with whole heart, cardiac chambers, and lung dose distribution parameters was collected, and the correlations to RVD were analyzed by means of Spearman's rank correlation coefficient (Rs). For the selection of the model order and parameters for NTCP modeling, a multivariate logistic regression method using resampling techniques (bootstrapping) was applied. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC). Results: When we analyzed the whole heart, a 3-variable NTCP model including the maximum dose, whole heart volume, and lung volume was shown to be the optimal predictive model for RVD (Rs = 0.573, P<.001, AUC = 0.83). When we analyzed the cardiac chambers individually, for the left atrium and for the left ventricle, an NTCP model based on 3 variables including the percentage volume exceeding 30 Gy (V30), cardiac chamber volume, and lung volume was selected as the most predictive model (Rs = 0.539, P<.001, AUC = 0.83; and Rs = 0.557, P<.001, AUC = 0.82, respectively). The NTCP values increase as heart maximum dose or cardiac chambers V30 increase. They also increase with larger volumes of the heart or cardiac chambers and decrease when lung volume is larger. Conclusions: We propose logistic NTCP models for RVD considering not only heart irradiation dose but also the combined effects of lung and heart volumes. Our study establishes the statistical evidence of the indirect effect of lung size on radio-induced heart toxicity

  14. Influence of heart rhythm, breathing and arm position during computed tomography scanning on the registration accuracy of electro anatomical map (EAM) images, left atrium three-dimensional computed tomography angiography images, and fluoroscopy time during ablation to treat atrial fibrillation

    International Nuclear Information System (INIS)

    Chono, Taiki; Shimoshige, Shinya; Yoshikawa, Kenta; Mizonobe, Kazuhusa; Ogura, Keishi

    2013-01-01

    In CARTOMERGE for treatment of atrial fibrillation (AF) by ablation, by integrating electro anatomical map (EAM) and left atrium three-dimensional computed tomography angiography (3D-CTA) images, identification of the ablation points is simplified and the procedure can be made carried out more rapidly. However, the influence that heart rhythm, breathing and arm position during CT scanning have on registration accuracy and fluoroscopy time is not clear. To clarify the influence on registration accuracy and fluoroscopy time of heart rhythm, breathing and arm position during CT scanning. The patients were CT-scanned during both sinus rhythm (SR) and AF in each study subject. We evaluated the registration accuracy of images reconstructed between the cardiac cycle and assessed the registration accuracy and fluoroscopy time of images obtained during inspiratory breath-hold, expiratory breath-hold and up and down position of the arm. Although the registration accuracy of the EAM image and left atrium 3D-CTA image showed a significant difference during SR, no significant difference was seen during AF. Expiratory breath-hold and down position of the arm resulted in the highest registration accuracy and the shortest fluoroscopy time. However, arm position had no significant effect on registration accuracy. Heart rhythm and breathing during CT scanning have a significant effect on the registration accuracy of EAM images, left atrium 3D-CTA images, and fluoroscopy time. (author)

  15. Prolonged Tp-e Interval in Down Syndrome Patients with Congenitally Normal Hearts.

    Science.gov (United States)

    Kucuk, Mehmet; Karadeniz, Cem; Ozdemir, Rahmi; Meşe, Timur

    2018-03-25

    Heterogeneity of ventricular repolarization has been assessed by using the QT dispersion in Down syndrome (DS) patients with congenitally normal hearts. However, novel repolarization indexes, the Tp-e interval and Tp-e/QT ratio, have not previously been evaluated in these patients. The aim of this study was to evaluate the Tp-e interval and Tp-e/QT ratio in DS patients without congenital heart defects. Twelve-lead surface electrocardiograms of 160 DS patients and 110 age- and sex-matched healthy controls were used to evaluate and compare the Tp-e interval, Tp-e dispersion, and Tp-e/QT ratio. Heart rate, Tp-e interval, Tp-e dispersion, Tp-e/QT and Tp-e/QTc ratios were significantly higher in DS group than in the controls. Myocardial repolarization indexes in DS patients with congenitally normal hearts were found to be prolonged compared to those in normal controls. Further evaluation is warranted to reveal a relationship between prolonged repolarization indexes and arrhythmic events in these patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  16. INDICATIONS FOR IMPLANTATION OF A PERMANENT DRIVER’S TRANSPLANTED HEART RHYTHM AND CHOICE OF A TREATMENT ELEKTROKARDIOSTIMULYATION

    Directory of Open Access Journals (Sweden)

    S. J. Shemakin

    2009-01-01

    Full Text Available This report presents retrospective analysis of using artificial pacemaker in 16 heart transplanted patients because of developmented bradiarithmic disfunctions in the early and later posttransplanted periods. DDDR or SSIR regimens are recommended for persistened disfuncion of sinus node. DDDR regimen is recommened to prevent atrio-ventricular conduction. 

  17. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    nature of the system underlying such rhythms and inspired one of the ... behaviours and physiological processes were discovered in a wide range of animals. ... is thought to coordinate internal physiology, and thereby confer benefits to living ...

  18. Catecholaminergic polymorphic ventricular tachycardia. An important diagnosis in children with syncope and normal heart

    Directory of Open Access Journals (Sweden)

    Luiz Roberto Leite

    2001-01-01

    Full Text Available Syncope in children is primarily related to vagal hyperreactivity, but ventricular tachycardia (VT way rarely be seen. Catecholaminergic polymorphic VT is a rare entity that can occur in children without heart disease and with a normal QT interval, which may cause syncope and sudden cardiac death. In this report, we describe the clinical features, treatment, and clinical follow-up of three children with syncope associated with physical effort or emotion and cathecolaminergic polymorphic VT. Symptoms were controlled with beta-blockers, but one patient died suddenly in the fourth year of follow-up. Despite the rare occurrence, catecholaminergic polymorphic VT is an important cause of syncope and sudden death in children with no identified heart disease and normal QT interval.

  19. [Magnetic resonance imaging in patients with implantable devices for treatment of disturbed heart rhythm: review of the current situation].

    Science.gov (United States)

    Sviridova, A A

    The question of the possibility of MRI scanning in patients with cardiac implantable electronic devices (CIED) appeared simultaneously with the introduction of MRI in clinical practice. A lot of in-vitro, in-vivo and clinical researches were performed to estimate wat going on with CIED in strong magnetic field and is it possible to perform some unified protocol of safe MRI-scanning for these patients. Recommendations were provided, but not for the wide practice. MRI remained strongly contraindicated for CIED patient. To meet the clinical need CIEM manufacturers changed the design of devices to made them MRI-compatible, including reducing of ferromagnetic components, additional filters, new software. Lead coil design was changed as well to minimize lead heating and electrical current induction. Now all leaders of CIED industry have in their portfolio all types of MRI-conditional implanted cardiac rhythm management devices (pacemakers, ICDs, CRTs). "Conditional" means MRI scanning can be done only under specific condition. For MRI device and lead in one system have to be from the same manufacturer. Now, if you need to implant the device, you must proceed from the fact that the patient is more likely to need an MRI in the future and choose the appropriate model, not forgetting that the electrodes should also be MRI-compatible.

  20. Heart Diseases and Disorders

    Science.gov (United States)

    ... Resources Heart Diseases & Disorders Back to Patient Resources Heart Diseases & Disorders Millions of people experience irregular or abnormal ... harmless and happen in healthy people free of heart disease. However, some abnormal heart rhythms can be serious ...

  1. Diastolic Function in Normal Sinus Rhythm vs. Chronic Atrial Fibrillation: Comparison by Fractionation of E-wave Deceleration Time into Stiffness and Relaxation Components.

    Science.gov (United States)

    Mossahebi, Sina; Kovács, Sándor J

    2014-01-01

    Although the electrophysiologic derangement responsible for atrial fibrillation (AF) has been elucidated, how AF remodels the ventricular chamber and affects diastolic function (DF) has not been fully characterized. The previously validated Parametrized Diastolic Filling (PDF) formalism models suction-initiated filling kinematically and generates error-minimized fits to E-wave contours using unique load (x o ), relaxation (c), and stiffness (k) parameters. It predicts that E-wave deceleration time (DT) is a function of both stiffness and relaxation. Ascribing DT s to stiffness and DTr to relaxation such that DT=DT s +DT r is legitimate because of causality and their predicted and observed high correlation (r=0.82 and r=0.94) with simultaneous (diastatic) chamber stiffness (dP/dV) and isovolumic relaxation (tau), respectively. We analyzed simultaneous echocardiography-cardiac catheterization data and compared 16 age matched, chronic AF subjects to 16, normal sinus rhythm (NSR) subjects (650 beats). All subjects had diastatic intervals. Conventional DF parameters (DT, AT, E peak , E dur , E-VTI, E/E') and E-wave derived PDF parameters (c, k, DT s , DT r ) were compared. Total DT and DT s , DT r in AF were shorter than in NSR (pwave DT in AF is due to stiffness compared to NSR. By trending individual subjects, this method can elucidate and characterize the beneficial or adverse long-term effects on chamber remodeling due to alternative therapies in terms of chamber stiffness and relaxation.

  2. Comprehensive risk reduction in patients with atrial fibrillation: emerging diagnostic and therapeutic options—a report from the 3rd Atrial Fibrillation Competence NETwork/European Heart Rhythm Association consensus conference

    Science.gov (United States)

    Kirchhof, Paulus; Lip, Gregory Y.H.; Van Gelder, Isabelle C.; Bax, Jeroen; Hylek, Elaine; Kaab, Stefan; Schotten, Ulrich; Wegscheider, Karl; Boriani, Giuseppe; Brandes, Axel; Ezekowitz, Michael; Diener, Hans; Haegeli, Laurent; Heidbuchel, Hein; Lane, Deirdre; Mont, Luis; Willems, Stephan; Dorian, Paul; Aunes-Jansson, Maria; Blomstrom-Lundqvist, Carina; Borentain, Maria; Breitenstein, Stefanie; Brueckmann, Martina; Cater, Nilo; Clemens, Andreas; Dobrev, Dobromir; Dubner, Sergio; Edvardsson, Nils G.; Friberg, Leif; Goette, Andreas; Gulizia, Michele; Hatala, Robert; Horwood, Jenny; Szumowski, Lukas; Kappenberger, Lukas; Kautzner, Josef; Leute, Angelika; Lobban, Trudie; Meyer, Ralf; Millerhagen, Jay; Morgan, John; Muenzel, Felix; Nabauer, Michael; Baertels, Christoph; Oeff, Michael; Paar, Dieter; Polifka, Juergen; Ravens, Ursula; Rosin, Ludger; Stegink, W.; Steinbeck, Gerhard; Vardas, Panos; Vincent, Alphons; Walter, Maureen; Breithardt, Günter; Camm, A. John

    2012-01-01

    While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section is covered, and suggestions for the improvement of management in each area are put forward. Combined, the propositions formulate a perspective to implement comprehensive management in AF. PMID:21791573

  3. Nonlinear and Stochastic Dynamics in the Heart

    Science.gov (United States)

    Qu, Zhilin; Hu, Gang; Garfinkel, Alan; Weiss, James N.

    2014-01-01

    In a normal human life span, the heart beats about 2 to 3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems. PMID:25267872

  4. Nonlinear and stochastic dynamics in the heart

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Zhilin, E-mail: zqu@mednet.ucla.edu [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Hu, Gang [Department of Physics, Beijing Normal University, Beijing 100875 (China); Garfinkel, Alan [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095 (United States); Weiss, James N. [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States)

    2014-10-10

    In a normal human life span, the heart beats about 2–3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems.

  5. Nonlinear and stochastic dynamics in the heart

    International Nuclear Information System (INIS)

    Qu, Zhilin; Hu, Gang; Garfinkel, Alan; Weiss, James N.

    2014-01-01

    In a normal human life span, the heart beats about 2–3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems

  6. Short-term exposure to ambient fine particulate matter (PM2,5 and PM10) and the risk of heart rhythm abnormalities and stroke.

    Science.gov (United States)

    Kowalska, Małgorzata; Kocot, Krzysztof

    2016-09-28

    Results of epidemiological studies suggest a significant impact of ambient particulate matter air pollution (PM10 and PM2,5) on the health of the population. Increased level of these pollutants is connected with increased rate of daily mortality and hospitalizations due to cardiovascular diseases. Among analyzed health effects, heart arrhythmias and stroke are mentioned most frequently. The aim of the study was to present the current knowledge of potential influence of the exposure to fine particulate matter on the presence of arrhythmias and strokes. Subject literature review suggests, that there is a link between short-term exposure to fine dust and the occurrence of arrhythmias. Results of previous studies indicates that this exposure may lead to significant electrophysiological changes in heart, resulting in higher susceptibility to cardiac rhythm abnormalities. In case of stroke, a stronger correlation between number of hospitalizations and death cases and exposure to fine dust was seen for ischaemic stroke than for haemorhhagic stroke. In addition, a significantly more harmful impact of the exposure to ultra particles (particles of aerodynamic diameter below 2,5 μm) has been confirmed. Among important mechanisms responsible for observed health impact of particulate matter there are: induction and intensification of inflammation, increased oxidative stress, increased autonomic nervous system activity, vasoconstriction, rheological changes and endothelial dysfunction. Among people of higher susceptibility to fine dust negative health impact are: elderly (over 65 years old), obese people, patients with respiratory and cardiovascular diseases, patients with diabetes and those with coagulation disorders. For further improvement of general health status, actions aimed at reducing the risk associated with fine dust and at the same time at continuing studies to clarify the biological mechanisms explaining the influence of fine dust on human health are necessary.

  7. Short-term exposure to ambient fine particulate matter (PM2,5 and PM10 and the risk of heart rhythm abnormalities and stroke

    Directory of Open Access Journals (Sweden)

    Małgorzata Kowalska

    2016-09-01

    Full Text Available Results of epidemiological studies suggest a significant impact of ambient particulate matter air pollution (PM10 and PM2,5 on the health of the population. Increased level of these pollutants is connected with increased rate of daily mortality and hospitalizations due to cardiovascular diseases. Among analyzed health effects, heart arrhythmias and stroke are mentioned most frequently. The aim of the study was to present the current knowledge of potential influence of the exposure to fine particulate matter on the presence of arrhythmias and strokes. Subject literature review suggests, that there is a link between short-term exposure to fine dust and the occurrence of arrhythmias. Results of previous studies indicates that this exposure may lead to significant electrophysiological changes in heart, resulting in higher susceptibility to cardiac rhythm abnormalities. In case of stroke, a stronger correlation between number of hospitalizations and death cases and exposure to fine dust was seen for ischaemic stroke than for haemorhhagic stroke. In addition, a significantly more harmful impact of the exposure to ultra particles (particles of aerodynamic diameter below 2,5 μm has been confirmed. Among important mechanisms responsible for observed health impact of particulate matter there are: induction and intensification of inflammation, increased oxidative stress, increased autonomic nervous system activity, vasoconstriction, rheological changes and endothelial dysfunction. Among people of higher susceptibility to fine dust negative health impact are: elderly (over 65 years old, obese people, patients with respiratory and cardiovascular diseases, patients with diabetes and those with coagulation disorders. For further improvement of general health status, actions aimed at reducing the risk associated with fine dust and at the same time at continuing studies to clarify the biological mechanisms explaining the influence of fine dust on human health

  8. Measurement of emotional contagion using synchronization of heart rhythm pattern between two persons: Application to sales managers and sales force synchronization.

    Science.gov (United States)

    Park, Sangin; Choi, Soo Ji; Mun, Sungchul; Whang, Mincheol

    2018-04-19

    The purpose of this study was to measure emotional contagion, determine its direction, and compare the intensity between positive and negative contagion using the synchronization of heart rhythm pattern (HRP). A total of 64 undergraduate students (32 women and 32 men) participated in the experiment, and were randomly categorized as either leaders or followers. Followers were required to imitate the facial expression (happy and sad) of the leader (emotional contagion) or of a facial image (emotional non-contagion). We found that emotional contagion significantly increased the correlation coefficient between leaders and followers' HRP for both positive and negative emotions, but emotional non-contagion did not. There was no significant difference in leaders' HRP before and after contagion, while followers' HRP changed significantly. During emotional contagion, the correlation coefficient for negative emotion was significantly higher than for positive emotion. The proposed method could measure low or high emotional contagion and determine its direction quantitatively. In our application study, a sales manager (leader) transmitted a positive emotion to a sales employee (follower), and the groups are organized as HEC or LEC (high or low emotional contagion) groups by evaluating the intensity of emotional contagion based on HRP synchrony between them. HEC group's performance was enhanced compared to the LEC group. Copyright © 2018. Published by Elsevier Inc.

  9. Determinants of geographic variations in implantation of cardiac defibrillators in the European Society of Cardiology member countries--data from the European Heart Rhythm Association White Book.

    Science.gov (United States)

    Lubinski, Andrzej; Bissinger, Andrzej; Boersma, Lucas; Leenhardt, Antoine; Merkely, Bela; Oto, Ali; Proclemer, Alessandro; Brugada, Josep; Vardas, Panos E; Wolpert, Christian

    2011-05-01

    Sudden cardiac death (SCD) is a major health concern in developed countries. Many studies have demonstrated the efficacy of implantable cardioverter defibrillator (ICD) therapy in the prevention of SCD and total mortality reduction. However, the high individual costs and the reimbursement policy may limit widespread ICD utilization. This study analyzed the temporal and the geographical trends of the ICD implantation rate. Data were gathered from two editions of the European Heart Rhythm Association (EHRA) White Books published in 2008 and 2009. The analysis revealed significant differences in the rates of ICD implantation per million capita between the countries, but the median implantations was constantly increasing. The number of ICD implantations correlated with gross domestic product (GDP), GDP per capita, expenditure on health, life expectancy, and the number of implanting centres. There are great number of differences in the ICD-implanting rates between EHRA member countries, consequent to the increase in the number of ICD implantations. The ICD implantation rates are related to national economic status and healthcare expenses.

  10. Factors related to outcome in heart failure with a preserved (or normal) left ventricular ejection fraction.

    Science.gov (United States)

    Sanderson, John E

    2016-07-01

    Heart failure with a preserved ejection faction (HFpEF) is a growing and expensive cause of heart failure (HF) affecting particularly the elderly. It differs in substantial ways in addition to the normal left ventricular ejection fraction, from the more easily recognized form of heart failure with a reduced ejection fraction (HFrEF or 'systolic heart failure') and unlike HFrEF there have been little advances in treatment. In part, this relates to the complexity of the pathophysiology and identifying the correct targets. In HFpEF, there appears to be widespread stiffening of the vasculature and the myocardium affecting ventricular function (both systolic and diastolic), impeding ventricular suction, and thus early diastolic filling leading to breathlessness on exertion and later atrial failure and fibrillation. Left ventricular ejection fraction tends to gradually decline and some evolve into HFrEF. Most patients also have a mixture of several co-morbidities including hypertension, diabetes, obesity, poor renal function, lack of fitness, and often poor social conditions. Therefore, many factors may influence outcome in an individual patient. In this review, the epidemiology, possible causation, pathophysiology, the influence of co-morbidities and some of the many potential predictors of outcome will be considered.

  11. Prognostic significance of hemoglobin level in patients with congestive heart failure and normal ejection fraction.

    Science.gov (United States)

    Varadarajan, Padmini; Gandhi, Siddharth; Sharma, Sanjay; Umakanthan, Branavan; Pai, Ramdas G

    2006-10-01

    Previous studies have shown low hemoglobin (Hb) to have an adverse effect on survival in patients with congestive heart failure (CHF) and reduced left ventricular (LV) ejection fraction (EF); but its effect on survival in patients with CHF and normal EF is not known. This study sought to determine whether low Hb has an effect on survival in patients with both CHF and normal EF. Detailed chart reviews were performed by medical residents on 2,246 patients (48% with normal EF) with a discharge diagnosis of CHF in a large tertiary care hospital from 1990 to 1999. The CHF diagnosis was validated using the Framingham criteria. Mortality data were obtained from the National Death Index. Survival analysis was performed using Kaplan-Meier and Cox regression models. By Kaplan-Meier analysis, low Hb (< 12 gm/dl) compared with normal hemoglobin was associated with a lower 5-year survival in patients with CHF and both normal (38 vs. 50%, p = 0.0008) and reduced (35 vs. 48%, p = 0.0009) EF. Using the Cox regression model, low Hb was an independent predictor of mortality after adjusting for age, gender, renal dysfunction, diabetes mellitus, hypertension, and EF in both groups of patients. Low Hb has an independent adverse effect on survival in patients with CHF and both normal and reduced EF in both groups of patients.

  12. Influence of peak exercise heart rate on normal thallium-201 myocardial clearance

    International Nuclear Information System (INIS)

    Kaul, S.; Chesler, D.A.; Pohost, G.M.; Strauss, H.W.; Okada, R.D.; Boucher, C.A.

    1986-01-01

    Measurement of myocardial clearance rates between initial and delayed images is a major justification for adding computer quantification to the interpretation of exercise 201 TI images. To clarify the range of normal thallium clearance and its relationship to the level of exercise achieved, exercise thallium images in 89 normal subjects were analyzed: 45 asymptomatic subjects with less than 1% probability of coronary artery disease (CAD) (Group I), and 44 patients with chest pain found to have no significant CAD on angiography (Group II). Mean initial regional thallium uptake was similar in the two groups, but myocardial thallium clearance (mean +/- 1 s.d.) was slower in Group II, expressed as a longer half-life in the myocardium (8.2 +/- 7.6 hr compared with 3.4 +/- 0.7 hr p less than 0.001). Analysis of variance using ten clinical and exercise variables as covariates showed that the slower clearance in Group II was related to a lower peak exercise heart rate (HR) (154 +/- 27 compared with 183 +/- 11, respectively, p less than 0.001). By linear regression analysis, a decrease in peak HR of 1 beat/min was associated with a slower thallium clearance (longer half-life) of 0.05 hr. Using this formula, the clearance value in each patient was then corrected for peak exercise heart rate by decreasing measured clearance by 0.05 hr multiplied by the amount peak exercise heart rate which was below 183 (the mean value in Group I). There were no differences in the corrected clearance between the two groups. We conclude that thallium myocardial clearance after exercise is related in part to factors other than the presence of CAD, being slower when peak exercise HR is lower. Therefore, thallium clearance rates alone uncorrected for peak exercise heart rate should be used with caution when diagnosing CAD

  13. Oral triiodothyronine normalizes triiodothyronine levels after surgery for pediatric congenital heart disease*.

    Science.gov (United States)

    Marwali, Eva M; Boom, Cindy E; Sakidjan, Indriwanto; Santoso, Anwar; Fakhri, Dicky; Kartini, Ay; Kekalih, Aria; Schwartz, Steven M; Haas, Nikolaus A

    2013-09-01

    This study was conducted to determine if oral triiodothyronine supplementation could prevent the decrease of serum triiodothyronine levels that commonly occurs after cardiopulmonary bypass for pediatric congenital heart surgery. Secondary objectives included identifying any significant adverse effects of oral triiodothyronine supplementation, including any effects on the thyroid/pituitary axis. Randomized, placebo-controlled, doubleblind clinical trial Operating room and ICU. Infants and children younger than 2 years of age undergoing congenital heart surgery using cardiopulmonary bypass (n = 43). Subjects were assigned to placebo (n = 15, group A) or one of two treatment groups: a low-dose group (group B, n = 14, 0.5 mcg/kg triiodothyronine orally every 24 hr for 3 d) or a high-dose group (group C, n = 14, 0.5 mcg/kg triiodothyronine orally every 12 hr for 3 d). Thyroid hormone, including total and free triiodothyronine levels at predetermined time points, potential side effects indicating hyperthyroidism, indicators of the thyroid-pituitary axis, and clinical endpoints. Oral triiodothyronine supplementation twice-daily maintained serum triiodothyronine levels within normal limits in group C, whereas serum levels progressively declined in groups A and B. A statistically significant difference in triiodothyronine levels between the treatment groups occurred between 18 and 36 hours post cross-clamp release, with the largest difference in serum levels between group C and group A noted at 36 hours post cross-clamp release (total triiodothyronine, 0.71 ± 0.15 [0.34-1.08] ng/mL [p triiodothyronine, 2.56 ± 0.49 [1.33-3.79] pg/mL [p triiodothyronine supplementation at a dose of 0.5 mcg/kg every 12 hours for 3 days can maintain total and free triiodothyronine levels within normal limits after open-heart surgery using cardiopulmonary bypass for congenital heart disease.

  14. Current strategy for treatment of patients with Wolff-Parkinson-White syndrome and asymptomatic preexcitation in Europe: European Heart Rhythm Association survey.

    Science.gov (United States)

    Svendsen, Jesper Hastrup; Dagres, Nikolaos; Dobreanu, Dan; Bongiorni, Maria Grazia; Marinskis, Germanas; Blomström-Lundqvist, Carina

    2013-05-01

    The aims of this survey was to provide insight into treatment activity, the strategy of treatment, and risk stratification of patients with asymptomatic and symptomatic ventricular pre-excitation across Europe. Fifty-eight centres, members of the European Heart Rhythm Association EP research network, covering 20 countries answered the survey questions. All centres were high-volume ablation centres. A younger person with asymptomatic Wolff-Parkinson-White (WPW) pattern has a higher likelihood of being risk-stratified or receiving ablation therapy compared with an older subject. Two-thirds of centres report that they have observed a decline in the number of patients ablated for an accessory pathway during the last 10 years. Pre-excited atrial fibrillation is rarely seen. Discontinuation of a scheduled WPW ablation due to close vicinity of the accessory pathway to the AV node happens very rarely. Patients with a first episode of pre-excited atrial fibrillation would immediately be referred for catheter ablation to be performed within weeks by 80.4% of the centres. A significant proportion of responders (50.9%) would use electrical cardioversion to restore sinus rhythm in a patient with pre-excited atrial fibrillation. With respect to the choice of antiarrhythmic medication for a patient with pre-excited AF, the majority (80.0%) would choose class 1C antiarrhytmic drugs while waiting for a catheter ablation. A patient seen in the emergency room with a second episode of orthodromic atrioventricular reentry tachycardia would be referred for immediate ablation by 79.2-90.6% of centres depending on the presence of pre-excitation. The volume of paediatric ablations performed on children younger than 12 years was low (46.4%: 0 patients per year; 46.4%: 1-9 patients per year). The majority of responding centres (61-69%) report that their country lack national guidelines dealing with clinical strategies related to WPW. There is a need for national guidelines dealing with

  15. Effects of music composed by Mozart and Ligeti on blood pressure and heart rate circadian rhythms in normotensive and hypertensive rats.

    Science.gov (United States)

    Lemmer, Björn

    2008-11-01

    There is continuing discussion on the effect of music ("Mozart effect") on numerous functions in man and experimental animals. Radiotelemetry now allows one to monitor cardiovascular functions in freely-moving unrestrained experimental animals. Radiotelemetry was used to monitor systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), and motor activity (MA) in male normotensive WKY and hypertensive SHR animals. Rats were synchronized to a 12 h light (L): 12 h dark (D) regimen in an isolated, ventilated, light-controlled, sound-isolated animal container. Music (Mozart, Symphony # 40; Ligeti, String Quartet # 2) were played for 2 h at 75 dB in the animal cabin starting at the onset of L or D in a cross-over design. Data were collected every 5 min for 24 h under control conditions and during and after music. In addition, plasma concentrations of norepinephrine (NE) were determined in unrestrained animals at 3 h intervals over 24 h. In both WKY and SHR, highly significant circadian rhythms were obtained in SBP, DBP, HR, and MA under control conditions; HR was lower and BP higher in SHR than in WKY. NE was circadian rhythmic in both strains with higher values in D; the increase in NE with immobilization was much more pronounced in SHR than in WKY. The music of Mozart had no effect on either parameter in WKY, neither in L nor in D. In contrast, in SHR, the music of Mozart presented in L significantly decreased HR and left BP unaffected, leading to a small decrease in cardiac output. The music of Ligeti significantly increased BP both in L and in D and reflexively reduced HR in L, the effects being long-lasting over 24 h. Interestingly, white noise at 75 dB had no effect at all on either function in both strains. The effects of both Mozart and Ligeti cannot be attributed to a stress reaction, as stress due to cage switch increased HR and BP both in WKY and SHR. The study clearly demonstrates that music of different character (tempo, rhythm, pitch, tonality) can

  16. Partial LVAD restores ventricular outputs and normalizes LV but not RV stress distributions in the acutely failing heart in silico

    OpenAIRE

    Sack, Kevin L.; Baillargeon, Brian; Acevedo-Bolton, Gabriel; Genet, Martin; Rebelo, Nuno; Kuhl, Ellen; Klein, Liviu; Weiselthaler, Georg M.; Burkhoff, Daniel; Franz, Thomas; Guccione, Julius M.

    2016-01-01

    Purpose: Heart failure is a worldwide epidemic that is unlikely to change as the population ages and life expectancy increases. We sought to detail significant recent improvements to the Dassault Systèmes Living Heart Model (LHM) and use the LHM to compute left ventricular (LV) and right ventricular (RV) myofiber stress distributions under the following 4 conditions: (1) normal cardiac function; (2) acute left heart failure (ALHF); (3) ALHF treated using an LV assist device (LVAD) flow rate o...

  17. RHYTHM DISTURBANCES DURING COLONOSCOPY

    Directory of Open Access Journals (Sweden)

    D. Jordanov

    2012-08-01

    Full Text Available Purpose: The purpose of this study is to assess the risk of inducing rhythm disturbances of the heart during colonoscopy.Patients and methods used: 80 patients had undergone colonoscopyper formed by two experienced specialists of endoscopy for the period from March to December 2011. The endoscopies were performed without premedication and sedation. Holter was placed on each patient one hour before the endoscopic examination, and the record continued one hour after the manipulation. The blood pressure was measured before, during and after the procedure.Results: During colonoscopy 25 patients (31,25% manifested rhythm disorders. In 15 patients (18,75% sinus tachycardia occurred. In 7 patients (8,75% suptraventricular extra systoles were observed and in 3 patients (3,75% - ventricular extra systoles. No ST-T changes were found. Highest values of the blood pressure were measured before and during the endoscopy, but the values did not exceed 160/105 mmHg. In 10 patients (12,5% a hypotensive reaction was observed, bur the values were not lower than 80/ 50. In 2 patients there was a short bradycardia with a heart frequency 50-55 /min.Conclusions: Our results showed that the rhythm disorders during lower colonoscopy occur in approximately 1/3 of the examined patients, there is an increase or decrease of the blood pressure in some patients, but that doesn’t require physician’s aid and the examination can be carried out safely without monitoring.

  18. Routine versus aggressive upstream rhythm control for prevention of early atrial fibrillation in heart failure : background, aims and design of the RACE 3 study

    NARCIS (Netherlands)

    Alings, M.; Smit, M. D.; Moes, M. L.; Crijns, H. J. G. M.; Tijssen, J. G. P.; Brugemann, J.; Hillege, H. L.; Lane, D. A.; Lip, G. Y. H.; Smeets, J. R. L. M.; Tieleman, R. G.; Tukkie, R.; Willems, F. F.; Vermond, R. A.; Van Veldhuisen, D. J.; Van Gelder, I. C.

    Rhythm control for atrial fibrillation (AF) is cumbersome because of its progressive nature caused by structural remodelling. Upstream therapy refers to therapeutic interventions aiming to modify the atrial substrate, leading to prevention of AF. The Routine versus Aggressive upstream rhythm Control

  19. Routine versus aggressive upstream rhythm control for prevention of early atrial fibrillation in heart failure: background, aims and design of the RACE 3 study

    NARCIS (Netherlands)

    Alings, M.; Smit, M. D.; Moes, M. L.; Crijns, H. J. G. M.; Tijssen, J. G. P.; Brügemann, J.; Hillege, H. L.; Lane, D. A.; Lip, G. Y. H.; Smeets, J. R. L. M.; Tieleman, R. G.; Tukkie, R.; Willems, F. F.; Vermond, R. A.; van Veldhuisen, D. J.; van Gelder, I. C.

    2013-01-01

    Rhythm control for atrial fibrillation (AF) is cumbersome because of its progressive nature caused by structural remodelling. Upstream therapy refers to therapeutic interventions aiming to modify the atrial substrate, leading to prevention of AF. The Routine versus Aggressive upstream rhythm Control

  20. Circadian Rhythms

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 11. Circadian Rhythms ... M Vaze1 Vijay Kumar Sharma1. Chronobiology Laboratory Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur, PO Box 6436, Bangalore 560 064, India.

  1. Circadian Rhythms

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 2. Circadian Rhythms: Why do ... Nikhil Vijay Kumar Sharma1. Chronobiology Laboratory Evolutionary and Organismal Biology Unit Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur, PO Box 6436, Bangalore 560 064, India.

  2. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    Early studies on circadian rhythms focussed on unravelling the fundamental .... careful analysis revealed that deaths of most arrhythmic indi- viduals were due to .... is no more a sci-fi movie script and is achievable through a technique called ...

  3. Thromboembolism and antithrombotic therapy for heart failure in sinus rhythm: an executive summary of a joint consensus document from the ESC Heart Failure Association and the ESC Working Group on Thrombosis.

    Science.gov (United States)

    Lip, Gregory Y H; Piotrponikowski, Piotr; Andreotti, Felicita; Anker, Stefan D; Filippatos, Gerasimos; Homma, Shunichi; Morais, Joao; Pullicino, Patrick; Rasmussen, Lars H; Marín, Francisco; Lane, Deirdre A

    2012-12-01

    Chronic heart failure (HF) with either reduced or preserved left ventricular (LV) ejection fraction is common and remains an extremely serious disorder with a high mortality and morbidity. Many complications related to heart failure can be related to thrombosis. Epidemiological and pathophysiological data also link HF to an increased risk of thrombosis, leading to the clinical consequences of sudden death, stroke, systemic thromboembolism and/or venous thromboembolism. This executive summary of a joint consensus document of the Heart Failure Association (EHFA) of the European Society of Cardiology (ESC) and the ESC Working Group on Thrombosis reviews the published evidence, summarises 'best practice', and puts forward consensus statements that may help to define evidence gaps and assist management decisions in everyday clinical practice. In HF patients with atrial fibrillation, oral anticoagulation is clearly recommended, and the CHA2DS2-VASc and HAS-BLED scores should be used to determine the likely risk-benefit ratio (thromboembolism prevention versus risk of bleeding) of oral anticoagulation. In HF patients with reduced LV ejection fraction who are in sinus rhythm there is no evidence of an overall benefit of vitamin K antagonists (e.g. warfarin) on mortality, with risk of major bleeding. Whilst there is the potential for a reduction in ischaemic stroke, there is currently no compelling reason to routinely use warfarin for these patients. Risk factors associated with increased risk of thromboembolic events should be identified and decisions regarding use of anticoagulation individualised. Patient values and preferences are important determinants when balancing the risk of thromboembolism against bleeding risk. Novel oral anticoagulants that offer a different risk-benefit profile compared with warfarin may appear as an attractive therapeutic option, but this would need to be confirmed in clinical trials.

  4. Impact of age and sex on normal left heart structure and function.

    Science.gov (United States)

    Hagström, Linn; Henein, Michael Y; Karp, Kjell; Waldenström, Anders; Lindqvist, Per

    2017-11-01

    Accurate age- and sex-related normal reference values of ventricular structure and function are important to determine the level of dysfunction in patients. The aim of this study therefore was to document normal age range sex-related measurements of LV structural and functional measurements to serve such purpose. We evaluated left ventricular structure and function in 293 healthy subjects between 20 and 90 years with equally distributed gender. Doppler echocardiography was used including measure of both systolic and diastolic functions. Due to systolic LV function, only long axis function correlated with age (r = 0·55, P<0·01) and the correlation was stronger in females. Concerning diastolic function, there was a strong age correlation in all parameters used (r = 0·40-0·74, P<0·001). Due to LV structural changes over age, females showed a larger reduction in end-diastolic volumes, but no or trivial difference in wall thickness after the age of 60 years. Age is associated with significant normal changes in left ventricular structure and function, which should be considered when deciding on normality. These changes are related to systemic arterial changes as well as body stature, thus reflecting overall body ageing process. Furthermore, normal cardiac ageing in females might partly explain the higher prevalence of heart failure with preserved ejection in females. © 2016 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  5. Profile of Cardiovascular Risk Factors in Patients with Coronary Heart Disease, Normal and Impaired Carbohydrate Metabolism

    Directory of Open Access Journals (Sweden)

    І.V. Cherniavska

    2015-11-01

    Full Text Available The aim of research was to conduct the comparative analysis of the profile of cardiovascular risk factors in patients with coronary heart disease (CHD and normal either impaired carbohydrate metabolism. Materials and methods. One hundred and forty two patients were observed. In order to estimate the rate of different forms of CHD depending on the state of carbohydrate metabolism such groups were formed: the first group consisted of 83 patients with type 2 diabetes mellitus (DM, the second group involved 34 patients with impaired glucose tolerance (IGT, the third group consisted of 25 patients with normal carbohydrate metabolism. The ischemic changes of myocardium were detected by ambulatory ECG monitoring with the obligatory achievement of submaximal heart rate during the research. Results. Silent myocardial ischemia was educed in 19 (22.9 % patients with type 2 DM, in 3 (8.8 % persons with IGT and in 2 (8.0 % patients with normal carbohydrate metabolism. Smoking, burdened heredity, violation in the haemostatic system more often occurred in the group of patients with type 2 DM and silent myocardial ischemia in comparison with the patients with type 2 DM without CHD. The profile of general population cardiovascular risk factors in patients with CHD and type 2 DM belongs to the most unfavorable. At the same time for patients with early violations of carbohydrate metabolism and normal carbohydrate metabolism such profile statistically does not differentiate meaningfully. Conclusions. Patients with type 2 DM and silent myocardial ischemia as compared to patients with type 2 DM without CHD have more expressed violations of indexes of general population cardiovascular risk factors for certain.

  6. Anatomy of the normal fetal heart: The basis for understanding fetal echocardiography

    Directory of Open Access Journals (Sweden)

    Beatriz Picazo-Angelin

    2018-01-01

    Full Text Available The rapid changes that have taken place in recent years in relation to techniques used to image the fetal heart have emphasized the need to have a detailed knowledge ofnormal cardiac anatomy. Without such knowledge, it is difficult, if not impossible, to recognize the multiple facets of congenital cardiac disease. From the inception of fetal echocardiographic screening, the importance of basic knowledge of cardiac anatomy has been well recognized. The current machines used for imaging, however, now make it possible potentially to recognize features not appreciated at the start of the specialty. So as to match the advances made in imaging, we have now revisited our understanding of normal cardiac anatomy in the mid-gestational fetus. This was made possible by our dissection of 10 fetal hearts, followed by production of addition histological sections that mimic the standard ultrasound views. The fetuses ranged in gestational age from between 20 and 28 weeks. We then correlated the obtained anatomic images with the corresponding ultrasonic images used in the standard fetal screening scan. We also interrogated the anatomic sections so as to clarify ongoing controversies regarding detailed features of the normal cardiac anatomy. We have been able to show that the views now obtained using current technology reveal many details of anatomy not always appreciated at earlier times. Knowledge of these features should now permit diagnosis of most congenital cardiac malformations. The anatomic-echocardiographic correlations additionally provide a valuable resource for both the understanding and teaching of fetal echocardiography.

  7. Statistics on the use of cardiac electronic devices and electrophysiological procedures in the European Society of Cardiology countries: 2014 report from the European Heart Rhythm Association.

    Science.gov (United States)

    Raatikainen, M J Pekka; Arnar, David O; Zeppenfeld, Katja; Merino, Jose Luis; Levya, Francisco; Hindriks, Gerhardt; Kuck, Karl-Heinz

    2015-01-01

    There has been large variations in the use of invasive electrophysiological therapies in the member countries of the European Society of Cardiology (ESC). The aim of this analysis was to provide comprehensive information on cardiac implantable electronic device (CIED) and catheter ablation therapy trends in the ESC countries over the last five years. The European Heart Rhythm Association (EHRA) has collected data on CIED and catheter ablation therapy since 2008. Last year 49 of the 56 ESC member countries provided data for the EHRA White Book. This analysis is based on the current and previous editions of the EHRA White Book. Data on procedure rates together with information on economic aspects, local reimbursement systems and training activities are presented for each ESC country and the five geographical ESC regions. In 2013, the electrophysiological procedure rates per million population were highest in Western Europe followed by the Southern and Northern European countries. The CIED implantation and catheter ablation rate was lowest in the Eastern European and in the non-European ESC countries, respectively. However, in some Eastern European countries with relative low gross domestic product procedure rates exceeded those of some wealthier Western countries, suggesting that economic resources are not the only driver for utilization of arrhythmia therapies. These statistics indicate that despite significant improvements, there still is considerable heterogeneity in the availability of arrhythmia therapies across the ESC area. Hopefully, these data will help identify areas for improvement and guide future activities in cardiac arrhythmia management. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  8. Circadian Rhythm Management System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The value of measuring sleep-wake cycles is significantly enhanced by measuring other physiological signals that depend on circadian rhythms (such as heart rate and...

  9. The Heart´s rhythm 'n' blues: Sex differences in circadian variation patterns of vagal activity vary by depressive symptoms in predominantly healthy employees.

    Science.gov (United States)

    Jarczok, Marc N; Aguilar-Raab, Corina; Koenig, Julian; Kaess, Michael; Borniger, Jeremy C; Nelson, Randy J; Hall, Martica; Ditzen, Beate; Thayer, Julian F; Fischer, Joachim E

    2018-03-15

    Successful regulation of emotional states is positively associated to mental health, while difficulties in regulating emotions are negatively associated to overall mental health and in particular associated with anxiety or depression symptoms. A key structure associated to socio-emotional regulatory processes is the central autonomic network. Activity in this structure is associated to vagal activity can be indexed noninvasively and simply by measures of peripheral cardiac autonomic modulations such as heart rate variability. Vagal activity exhibits a circadian variation pattern, with a maximum during nighttime. Depression is known to affect chronobiology. Also, depressive symptoms are known to be associated with decreased resting state vagal activity, but studies investigating the association between circadian variation pattern of vagal activity and depressive symptoms are scarce. We aim to examine these patterns in association to symptom severity of depression using chronobiologic methods. Data from the Manheim Industrial Cohort Studies (MICS) were used. A total of 3,030 predominantly healthy working adults underwent, among others, ambulatory 24-h hear rate-recordings, detailed health examination and online questionnaires and were available for this analysis. The root mean sum of successive differences (RMSSD) was used as an indicator of vagally mediated heart rate variability. Three individual-level cosine function parameters (MESOR, amplitude, acrophase) were estimated to quantify circadian variation pattern. Multivariate linear regression models including important covariates such as age, sex, and lifestyle factors as well as an interaction effect of sex with depressive symptoms were used to estimate the association of circadian variation pattern of vagal activity with depressive symptoms simultaneously. The analysis sample consisted of 20.2% females and an average age 41 with standard deviation of 11 years. Nonparametric bivariate analysis revealed

  10. Thrombo-embolism and antithrombotic therapy for heart failure in sinus rhythm. A joint consensus document from the ESC Heart Failure Association and the ESC Working Group on Thrombosis.

    Science.gov (United States)

    Lip, Gregory Y H; Ponikowski, Piotr; Andreotti, Felicita; Anker, Stefan D; Filippatos, Gerasimos; Homma, Shunichi; Morais, Joao; Pullicino, Patrick; Rasmussen, Lars H; Marin, Francisco; Lane, Deirdre A

    2012-07-01

    Chronic heart failure (HF) with either reduced or preserved ejection fraction is common and remains an extremely serious disorder with a high mortality and morbidity. Many complications related to HF can be related to thrombosis. Epidemiological and pathophysiological data also link HF to an increased risk of thrombosis, leading to the clinical consequences of sudden death, stroke, systemic thrombo-embolism, and/or venous thrombo-embolism. This consensus document of the Heart Failure Association (EHFA) of the European Society of Cardiology (ESC) and the ESC Working Group on Thrombosis reviews the published evidence and summarizes 'best practice', and puts forward consensus statements that may help to define evidence gaps and assist management decisions in everyday clinical practice. In HF patients with atrial fibrillation, oral anticoagulation is recommended, and the CHA(2)DS(2)-VASc and HAS-BLED scores should be used to determine the likely risk-benefit ratio (thrombo-embolism prevention vs. risk of bleeding) of oral anticoagulation. In HF patients with reduced left ventricular ejection fraction who are in sinus rhythm there is no evidence of an overall benefit of vitamin K antagonists (e.g. warfarin) on mortality, with risk of major bleeding. Despite the potential for a reduction in ischaemic stroke, there is currently no compelling reason to use warfarin routinely for these patients. Risk factors associated with increased risk of thrombo-embolic events should be identified and decisions regarding use of anticoagulation individualized. Patient values and preferences are important determinants when balancing the risk of thrombo-embolism against bleeding risk. New oral anticoagulants that offer a different risk-benefit profile compared with warfarin may appear as an attractive therapeutic option, but this would need to be confirmed in clinical trials.

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

    International Nuclear Information System (INIS)

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

    1984-01-01

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

  12. Stable isotope ratios in hair and teeth reflect biologic rhythms.

    Directory of Open Access Journals (Sweden)

    Otto Appenzeller

    Full Text Available Biologic rhythms give insight into normal physiology and disease. They can be used as biomarkers for neuronal degenerations. We present a diverse data set to show that hair and teeth contain an extended record of biologic rhythms, and that analysis of these tissues could yield signals of neurodegenerations. We examined hair from mummified humans from South America, extinct mammals and modern animals and people, both healthy and diseased, and teeth of hominins. We also monitored heart-rate variability, a measure of a biologic rhythm, in some living subjects and analyzed it using power spectra. The samples were examined to determine variations in stable isotope ratios along the length of the hair and across growth-lines of the enamel in teeth. We found recurring circa-annual periods of slow and fast rhythms in hydrogen isotope ratios in hair and carbon and oxygen isotope ratios in teeth. The power spectra contained slow and fast frequency power, matching, in terms of normalized frequency, the spectra of heart rate variability found in our living subjects. Analysis of the power spectra of hydrogen isotope ratios in hair from a patient with neurodegeneration revealed the same spectral features seen in the patient's heart-rate variability. Our study shows that spectral analysis of stable isotope ratios in readily available tissues such as hair could become a powerful diagnostic tool when effective treatments and neuroprotective drugs for neurodegenerative diseases become available. It also suggests that similar analyses of archaeological specimens could give insight into the physiology of ancient people and animals.

  13. Systolic Strain Abnormalities to Predict Hospital Readmission in Patients With Heart Failure and Normal Ejection Fraction

    Science.gov (United States)

    Borer, Steven M.; Kokkirala, Aravind; O'Sullivan, David M.; Silverman, David I.

    2011-01-01

    Background Despite intensive investigation, the pathogenesis of heart failure with normal ejection fraction (HFNEF) remains unclear. We hypothesized that subtle abnormalities of systolic function might play a role, and that abnormal systolic strain and strain rate would provide a marker for adverse outcomes. Methods Patients of new CHF and left ventricular ejection fraction > 50% were included. Exclusion criteria were recent myocardial infarction, severe valvular heart disease, severe left ventricular hypertrophy (septum >1.8 cm), or a technically insufficient echocardiogram. Average peak systolic strain and strain rate were measured using an off-line grey scale imaging technique. Systolic strain and strain rate for readmitted patients were compared with those who remained readmission-free. Results One hundred consecutive patients with a 1st admission for HFNEF from January 1, 2004 through December 31, 2007, inclusive, were analyzed. Fifty two patients were readmitted with a primary diagnosis of heart failure. Systolic strain and strain rates were reduced in both study groups compared to controls. However, systolic strain did not differ significantly between the two groups (-11.7% for those readmitted compared with -12.9% for those free from readmission, P = 0.198) and systolic strain rates also were similar (-1.05 s-1 versus -1.09 s-1, P = 0.545). E/e’ was significantly higher in readmitted patients compared with those who remained free from readmission (14.5 versus 11.0, P = 0.013). E/e’ (OR 1.189, 95% CI 1.026-1.378; P = 0.021) was found to be an independent predictor for HFNEF readmission. Conclusions Among patients with new onset HFNEF, SS and SR rates are reduced compared with patients free of HFNEF, but do not predict hospital readmission. Elevated E/e’ is a predictor of readmission in these patients. PMID:28352395

  14. Potential fields on the ventricular surface of the exposed dog heart during normal excitation.

    Science.gov (United States)

    Arisi, G; Macchi, E; Baruffi, S; Spaggiari, S; Taccardi, B

    1983-06-01

    We studied the normal spread of excitation on the anterior and posterior ventricular surface of open-chest dogs by recording unipolar electrograms from an array of 1124 electrodes spaced 2 mm apart. The array had the shape of the ventricular surface of the heart. The electrograms were processed by a computer and displayed as epicardial equipotential maps at 1-msec intervals. Isochrone maps also were drawn. Several new features of epicardial potential fields were identified: (1) a high number of breakthrough points; (2) the topography, apparent widths, velocities of the wavefronts and the related potential drop; (3) the topography of positive potential peaks in relation to the wavefronts. Fifteen to 24 breakthrough points were located on the anterior, and 10 to 13 on the posterior ventricular surface. Some were in previously described locations and many others in new locations. Specifically, 3 to 5 breakthrough points appeared close to the atrioventricular groove on the anterior right ventricle and 2 to 4 on the posterior heart aspect; these basal breakthrough points appeared when a large portion of ventricular surface was still unexcited. Due to the presence of numerous breakthrough points on the anterior and posterior aspect of the heart which had not previously been described, the spread of excitation on the ventricular surface was "mosaic-like," with activation wavefronts spreading in all directions, rather than radially from the two breakthrough points, as traditionally described. The positive potential peaks which lay ahead of the expanding wavefronts moved along preferential directions which were probably related to the myocardial fiber direction.

  15. Blood pressure and heart rate variability analysis of orthostatic challenge in normal human pregnancies.

    Science.gov (United States)

    Heiskanen, Nonna; Saarelainen, Heli; Valtonen, Pirjo; Lyyra-Laitinen, Tiina; Laitinen, Tomi; Vanninen, Esko; Heinonen, Seppo

    2008-11-01

    The aim of the present study was to evaluate pregnancy-related changes in autonomic regulatory functions in healthy subjects. We studied cardiovascular autonomic responses to head-up tilt (HUT) in 28 pregnant women during the third trimester of pregnancy and 3 months after parturition. The maternal ECG and non-invasive beat-to-beat blood pressure were recorded in the horizontal position (left-lateral position) and during HUT in the upright position. Stroke volume was assessed from blood pressure signal by using the arterial pulse contour method. Heart rate variability (HRV) was analysed in frequency domain, and baroreflex sensitivity by the cross-spectral and the sequence methods. In the horizontal position, all frequency components of HRV were lower during pregnancy than 3 months after parturition (P pregnancy had no influence on normalized low frequency and high frequency powers. During pregnancy haemodynamics was well balanced with only minor changes in response to postural change while haemodynamic responses to HUT were more remarkable after parturition. In pregnant women HRV and especially its very low frequency component increased in response to HUT, whereas at 3 months after parturition the direction of these changes was opposite. Parasympathetic deactivation towards term is likely to contribute to increased heart rate and cardiac output at rest, whereas restored sympathetic modulation with modest responses may contribute stable peripheral resistance and sufficient placental blood supply under stimulated conditions. It is important to understand cardiovascular autonomic nervous system and haemodynamic control in normal pregnancy before being able to judge whether they are dysregulated in complicated pregnancies.

  16. How are patients with atrial fibrillation approached and informed about their risk profile and available therapies in Europe? Results of the European Heart Rhythm Association Survey.

    Science.gov (United States)

    Potpara, Tatjana S; Pison, Laurent; Larsen, Torben B; Estner, Heidi; Madrid, Antonio; Blomström-Lundqvist, Carina

    2015-03-01

    This European Heart Rhythm (EHRA) Scientific Initiatives Committee EP Wire Survey aimed at exploring the common practices in approaching patients with atrial fibrillation (AF) and informing them about their risk profiles and available therapies in Europe. In the majority of 53 responding centres, patients were seen by cardiologists (86.8%) or arrhythmologists (64.2%). First- and follow-up visits most commonly lasted 21-30 and 11-20 min (41.5 and 69.8% of centres, respectively). In most centres (80.2%) stroke and bleeding risk had the highest priority for discussion with AF patients; 50.9% of centres had a structured patient education programme for stroke prevention. Individual patient stroke risk was assessed at every visit in 69.2% of the centres; 46.1% of centres had a hospital-based anticoagulation clinic. Information about non-vitamin K oral anticoagulants (NOACs) was communicated to all AF patients eligible for oral anticoagulation (38.5% of centres) or to warfarin-naive/unstable patients (42.3%). Only two centres (3.8%) had a structured NOAC adherence follow-up programme; in eight centres (15.4%) patients were requested to sign the statement they have been informed about the risks of non-adherence to NOAC therapy, and three centres (5.8%) had a patient education programme. Patient preferences were of the highest relevance regarding oral anticoagulation and AF ablation (64.7 and 49.0% of centres, respectively). This EP Wire Survey shows that in Europe considerable amount of time and resources are used in daily clinical practice to inform AF patients about their risk profile and available therapies. However, a diversity of strategies used across the European hospitals was noted, and further research is needed to better define optimal strategies for informing AF patients about their risk profile and treatment options. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  17. The 2018 European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: executive summary.

    Science.gov (United States)

    Steffel, Jan; Verhamme, Peter; Potpara, Tatjana S; Albaladejo, Pierre; Antz, Matthias; Desteghe, Lien; Georg Haeusler, Karl; Oldgren, Jonas; Reinecke, Holger; Roldan-Schilling, Vanessa; Rowell, Nigel; Sinnaeve, Peter; Collins, Ronan; Camm, A John; Heidbüchel, Hein

    2018-03-19

    The current manuscript is the Executive Summary of the second update to the original Practical Guide, published in 2013. Non-vitamin K antagonist oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with atrial fibrillation (AF), and have emerged as the preferred choice, particularly in patients newly started on anticoagulation. Both physicians and patients are becoming more accustomed to the use of these drugs in clinical practice. However, many unresolved questions on how to optimally use these agents in specific clinical situations remain. The European Heart Rhythm Association (EHRA) set out to co-ordinate a unified way of informing physicians on the use of the different NOACs. A writing group identified 20 topics of concrete clinical scenarios for which practical answers were formulated, based on available evidence. The 20 topics are (i) eligibility for NOACs; (ii) practical start-up and follow-up scheme for patients on NOACs; (iii) ensuring adherence to prescribed oral anticoagulant intake; (iv) switching between anticoagulant regimens; (v) pharmacokinetics and drug-drug interactions of NOACs; (vi) NOACs in patients with chronic kidney or advanced liver disease; (vii) how to measure the anticoagulant effect of NOACs; (viii) NOAC plasma level measurement: rare indications, precautions, and potential pitfalls; (ix) how to deal with dosing errors; (x) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a potential risk of bleeding; (xi) management of bleeding under NOAC therapy; (xii) patients undergoing a planned invasive procedure, surgery or ablation; (xiii) patients requiring an urgent surgical intervention; (xiv) patients with AF and coronary artery disease; (xv) avoiding confusion with NOAC dosing across indications; (xvi) cardioversion in a NOAC-treated patient; (xvii) AF patients presenting with acute stroke while on NOACs; (xviii) NOACs in special

  18. ALCOHOL AND HEART RHYTHM DISORDERS

    Directory of Open Access Journals (Sweden)

    A. O. Yusupova

    2015-01-01

    Full Text Available Alcohol abuse and particularly extension of alcohol consumption in alcohol diseas increases the risk of cardiac arrhythmias development and aggravates existing arrhythmias. Patients do not always receive the necessary specific treatment due to lack of detection of the ethanol genesis of these arrhythmias. Management of patients with alcohol abuse and alcohol dependence, including its cardiac complications among other cardiac arrhythmias should use both antiarrhythmic and anti-alcohol drugs and antidepressants. Such issues as diagnosis and management of patients with alcohol-induced cardiac arrhythmias are presented.

  19. Substances and Heart Rhythm Disorders

    Science.gov (United States)

    ... drink coffee or tea or eat chocolate. Red wine and eating too much can bring about symptoms ... Now Governance Corporate Relations & Support Membership Join HRS Benefits My HRS FHRS Member Directory FAQs News Press ...

  20. Acute adjustments of heart rate and oxygen consuption in an experimental protocol of step training with diferent combinations of platform height and musical rhythms - doi: 10.4025/actascihealthsci.v35i2.11669

    Directory of Open Access Journals (Sweden)

    Viviane Ribeiro de Ávila

    2013-06-01

    Full Text Available The aim of this study was to investigate adaptations acute heart rate (HR and oxygen consumption (VO2 in an experimental protocol of step training with different combinations of platform height (15.2, 20.3 and 25.4 cm and musical rhythms (125, 135 and 145 bpm. Thirty-five women were randomly selected, (mean ± DP aged 21.6 ± 1.8 years, body weight of 57.8 ± 8.2 kg, height of 162.6 ± 6.8 cm, body mass index of 21.8 ± 2.5 kg m-2 and fat percentage (% Fat of 24.8 ± 4.4%, with at least six months experience in step training sessions, and a frequency of at least two days a week. Techniques of descriptive and inferential statistics were employed. A significant difference was detected for the HR and VO2 in relation to the increase in step platform height and in musical rhythm for all the combinations, except for three situations. From the obtained results, we can infer that the cardiovascular and metabolic responses increase or decrease according to the musical rhythm and/or platform height.

  1. Coronary heart disease patients transitioning to a normal life: perspectives and stages identified through a grounded theory approach.

    Science.gov (United States)

    Najafi Ghezeljeh, Tahereh; Yadavar Nikravesh, Mansoureh; Emami, Azita

    2014-02-01

    To explore how Iranian patients with coronary heart disease experience their lives. Coronary heart disease is a leading cause of death in Iran and worldwide. Understanding qualitatively how patients experience the acute and postacute stages of this chronic condition is essential knowledge for minimising the negative consequences of coronary heart disease. Qualitative study using grounded theory for the data analysis. Data for this study were collected through individual qualitative interviews with 24 patients with coronary heart disease, conducted between January 2009 and January 2011. Patients with angina pectoris were selected for participation through purposive sampling, and sample size was determined by data saturation. Data analysis began with initial coding and continued with focused coding. Categories were determined, and the core category was subsequently developed and finalised. The main categories of the transition from acute phase to a modified or 'new normal' life were: (1) Loss of normal life. Experiencing emotions and consequences of illness; (2) Coming to terms. Using coping strategies; (3) Recreating normal life. Healthcare providers must correctly recognise the stages of transition patients navigate while coping with coronary heart disease to support and educate them appropriately throughout these stages. Patients with coronary heart disease lose their normal lives and must work towards recreating a revised life using coping strategies that enable them to come to terms with their situations. By understanding Iranian patients' experiences, healthcare providers and especially nurses can use the information to support and educate patients with coronary heart disease on how to more effectively deal with their illness and its consequences. © 2013 John Wiley & Sons Ltd.

  2. Effect of Nebivolol on MIBG Parameters and Exercise in Heart Failure with Normal Ejection Fraction

    Energy Technology Data Exchange (ETDEWEB)

    Messias, Leandro Rocha, E-mail: lmessias@cardiol.br; Ferreira, Aryanne Guimarães; Miranda, Sandra Marina Ribeiro de; Teixeira, José Antônio Caldas [Universidade Federal Fluminense, Rio de Janeiro, RJ (Brazil); Azevedo, Jader Cunha de [Universidade Federal Fluminense, Rio de Janeiro, RJ (Brazil); Hospital Procardíaco, Rio de Janeiro, RJ (Brazil); Messias, Ana Carolina Nader Vasconcelos [Hospital Federal dos Servidores do Estado do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Maróstica, Elisabeth [Universidade Federal Fluminense, Rio de Janeiro, RJ (Brazil); Mesquita, Claudio Tinoco [Universidade Federal Fluminense, Rio de Janeiro, RJ (Brazil); Hospital Procardíaco, Rio de Janeiro, RJ (Brazil)

    2016-05-15

    More than 50% of the patients with heart failure have normal ejection fraction (HFNEF). Iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy and cardiopulmonary exercise test (CPET) are prognostic markers in HFNEF. Nebivolol is a beta-blocker with vasodilating properties. To evaluate the impact of nebivolol therapy on CPET and123I-MIBG scintigraphic parameters in patients with HFNEF. Twenty-five patients underwent 123I-MIBG scintigraphy to determine the washout rate and early and late heart-to-mediastinum ratios. During the CPET, we analyzed the systolic blood pressure (SBP) response, heart rate (HR) during effort and recovery (HRR), and oxygen uptake (VO{sub 2}). After the initial evaluation, we divided our cohort into control and intervention groups. We then started nebivolol and repeated the tests after 3 months. After treatment, the intervention group showed improvement in rest SBP (149 mmHg [143.5-171 mmHg] versus 135 mmHg [125-151 mmHg, p = 0.016]), rest HR (78 bpm [65.5-84 bpm] versus 64.5 bpm [57.5-75.5 bpm, p = 0.028]), peak SBP (235 mmHg [216.5-249 mmHg] versus 198 mmHg [191-220.5 mmHg], p = 0.001), peak HR (124.5 bpm [115-142 bpm] versus 115 bpm [103.7-124 bpm], p= 0.043), HRR on the 1st minute (6.5 bpm [4.75-12.75 bpm] versus 14.5 bpm [6.7-22 bpm], p = 0.025) and HRR on the 2nd minute (15.5 bpm [13-21.75 bpm] versus 23.5 bpm [16-31.7 bpm], p = 0.005), but no change in peak VO{sub 2} and 123I-MIBG scintigraphic parameters. Despite a better control in SBP, HR during rest and exercise, and improvement in HRR, nebivolol failed to show a positive effect on peak VO2 and 123I-MIBG scintigraphic parameters. The lack of effect on adrenergic activity may be the cause of the lack of effect on functional capacity.

  3. 31P MR spectroscopic measurement of intracellular pH in normal human hearts

    International Nuclear Information System (INIS)

    Kwon, Jae Hyun; Lee, Hui Joong; Jang, Yong Min

    2002-01-01

    To assess the usefulness of intracellular pH (pHi), calculated by determining the shift of a high-energy metabolite such as inorganic phosphate (Pi) of γ-ATP after performing MRS with ECG-gated two-dimensional 31 P CSI (chemical shift imaging), as a parameter for the overall state of the intracellular milieu. Proto decoupled 31 P CSI was performed on a 1.5-T scanner using a 1 H 31 P dual-tuned surface coil. Cardiac MRS data were obtained from eight normal volunteers aged 24-32 years with no history of heart disease. From the spectra obtained from several regions of the heart, peack position and peak area were estimated. The metabolic ratios of α-, β-, γ-ATP, PCr, Pi, phosphodiester and diphosphoglycerate were calculated, and pHi was estimated from the chemical shift of Pi and γ-ATP resonance. We then compared the data for the anterior myocardium with those previously published. The major phosphorous metabolites identified in these human hearts were as follows: PCr, at -0.1 to +0.1 ppm; three phosphate peaks from ATP, with a chemical shift centered at about -2.7 ppm (γ-ATP), -7.8 ppm (α-ATP), and -16.3 ppm (β-ATP); and phosphodiester (PDE) at 2-3 ppm, inorganic phosphate (Pi) at 4.5-5.4 ppm, and diphosphoglycerate (DPG) at 5.4-6.3 ppm. The PCr/β-ATP ratio was 2.20±0.17 and the PDE/β-ATP ratio, 1.04±0.09 pHi readings were 7.31±0.23 (calculated by the shift of Pi) and 6.81±0.20 (calculated by the shift of γ-ATP). Pi/PCR was 0.539, a ratio higher than that mentioned in previously published reports. The measurement of intracellular metabolism was affected by various kinds of factors. We believe, however, that pHi readings indicate the overall state of the cardiac intracellular milieu. An unexpected pHi readings, seen at MRS, may reflect errors in the MR procedure itself and, or in the analytical method

  4. {sup 31}P MR spectroscopic measurement of intracellular pH in normal human hearts

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jae Hyun; Lee, Hui Joong; Jang, Yong Min [Kyungpook National Univ., Taegu (Korea, Republic of)] [and others

    2002-05-01

    To assess the usefulness of intracellular pH (pHi), calculated by determining the shift of a high-energy metabolite such as inorganic phosphate (Pi) of {gamma}-ATP after performing MRS with ECG-gated two-dimensional {sup 31}P CSI (chemical shift imaging), as a parameter for the overall state of the intracellular milieu. Proto decoupled {sup 31}P CSI was performed on a 1.5-T scanner using a {sup 1}H{sup 31}P dual-tuned surface coil. Cardiac MRS data were obtained from eight normal volunteers aged 24-32 years with no history of heart disease. From the spectra obtained from several regions of the heart, peack position and peak area were estimated. The metabolic ratios of {alpha}-, {beta}-, {gamma}-ATP, PCr, Pi, phosphodiester and diphosphoglycerate were calculated, and pHi was estimated from the chemical shift of Pi and {gamma}-ATP resonance. We then compared the data for the anterior myocardium with those previously published. The major phosphorous metabolites identified in these human hearts were as follows: PCr, at -0.1 to +0.1 ppm; three phosphate peaks from ATP, with a chemical shift centered at about -2.7 ppm ({gamma}-ATP), -7.8 ppm ({alpha}-ATP), and -16.3 ppm ({beta}-ATP); and phosphodiester (PDE) at 2-3 ppm, inorganic phosphate (Pi) at 4.5-5.4 ppm, and diphosphoglycerate (DPG) at 5.4-6.3 ppm. The PCr/{beta}-ATP ratio was 2.20{+-}0.17 and the PDE/{beta}-ATP ratio, 1.04{+-}0.09 pHi readings were 7.31{+-}0.23 (calculated by the shift of Pi) and 6.81{+-}0.20 (calculated by the shift of {gamma}-ATP). Pi/PCR was 0.539, a ratio higher than that mentioned in previously published reports. The measurement of intracellular metabolism was affected by various kinds of factors. We believe, however, that pHi readings indicate the overall state of the cardiac intracellular milieu. An unexpected pHi readings, seen at MRS, may reflect errors in the MR procedure itself and, or in the analytical method.

  5. Effect of Nebivolol on MIBG Parameters and Exercise in Heart Failure with Normal Ejection Fraction

    International Nuclear Information System (INIS)

    Messias, Leandro Rocha; Ferreira, Aryanne Guimarães; Miranda, Sandra Marina Ribeiro de; Teixeira, José Antônio Caldas; Azevedo, Jader Cunha de; Messias, Ana Carolina Nader Vasconcelos; Maróstica, Elisabeth; Mesquita, Claudio Tinoco

    2016-01-01

    More than 50% of the patients with heart failure have normal ejection fraction (HFNEF). Iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy and cardiopulmonary exercise test (CPET) are prognostic markers in HFNEF. Nebivolol is a beta-blocker with vasodilating properties. To evaluate the impact of nebivolol therapy on CPET and123I-MIBG scintigraphic parameters in patients with HFNEF. Twenty-five patients underwent 123I-MIBG scintigraphy to determine the washout rate and early and late heart-to-mediastinum ratios. During the CPET, we analyzed the systolic blood pressure (SBP) response, heart rate (HR) during effort and recovery (HRR), and oxygen uptake (VO 2 ). After the initial evaluation, we divided our cohort into control and intervention groups. We then started nebivolol and repeated the tests after 3 months. After treatment, the intervention group showed improvement in rest SBP (149 mmHg [143.5-171 mmHg] versus 135 mmHg [125-151 mmHg, p = 0.016]), rest HR (78 bpm [65.5-84 bpm] versus 64.5 bpm [57.5-75.5 bpm, p = 0.028]), peak SBP (235 mmHg [216.5-249 mmHg] versus 198 mmHg [191-220.5 mmHg], p = 0.001), peak HR (124.5 bpm [115-142 bpm] versus 115 bpm [103.7-124 bpm], p= 0.043), HRR on the 1st minute (6.5 bpm [4.75-12.75 bpm] versus 14.5 bpm [6.7-22 bpm], p = 0.025) and HRR on the 2nd minute (15.5 bpm [13-21.75 bpm] versus 23.5 bpm [16-31.7 bpm], p = 0.005), but no change in peak VO 2 and 123I-MIBG scintigraphic parameters. Despite a better control in SBP, HR during rest and exercise, and improvement in HRR, nebivolol failed to show a positive effect on peak VO2 and 123I-MIBG scintigraphic parameters. The lack of effect on adrenergic activity may be the cause of the lack of effect on functional capacity

  6. Holiday season for a healthy heart.

    Science.gov (United States)

    Stamps, Deborah C; Carr, Marcella L

    2012-12-01

    The term "holiday heart" is defined as an acute cardiac arrhythmia or conduction disturbance associated with heavy alcohol intake in individuals with no known heart disease, but in whom heart rhythm is restored to normal with abstinence of alcohol. This article provides a brief overview of the literature on this topic, discusses causes of increased cardiac events during the holiday season, describes a patient profile and the effect on patients' health as well as on their families, and provides suggestions to decrease the risk of holiday heart during the festive season. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Circadian melatonin concentration rhythm is lost in pregnant women with altered blood pressure rhythm.

    Science.gov (United States)

    Tranquilli, A L; Turi, A; Giannubilo, S R; Garbati, E

    2004-03-01

    We assessed the correlation between the rhythm of melatonin concentration and circadian blood pressure patterns in normal and hypertensive pregnancy. Ambulatory 24-h blood pressure and blood samples every 4 h were monitored in 16 primigravidae who had shown an abnormal circadian blood pressure pattern (eight pre-eclamptic and eight normotensive) in pregnancy and 6-12 months after pregnancy. The circadian rhythm was analyzed by chronobiological measures. Eight normotensive women with maintained blood pressure rhythm served as controls. During pregnancy, melatonin concentration was significantly higher in pre-eclamptic than in normotensive women (pre-eclampsia, 29.4 +/- 1.9 pg/ml, normotensin, altered rhythm, 15.6 +/- 2.1; controls, 22.7 +/- 1.8; p lost in all pregnant women with loss of blood pressure rhythm. After pregnancy, normotensive women showed a reappearance of both melatonin and blood pressure rhythm, whereas pre-eclamptic women showed a reappearance of blood pressure but not melatonin rhythm. The loss of blood pressure rhythm in pregnancy is consistent with the loss of melatonin concentration rhythm. In pre-eclamptic women, the normalization of blood pressure rhythm, while melatonin rhythm remained altered, suggests a temporal or causal priority of circadian concentration of melatonin in the determination of blood pressure trend.

  8. Timing of left heart base descent in dogs with dilated cardiomyopathy and normal dogs.

    Science.gov (United States)

    Simpson, Kerry E; Devine, Bryan C; Woolley, Richard; Corcoran, Brendan M; French, Anne T

    2008-01-01

    The identification and assessment of myocardial failure in canine idiopathic dilated cardiomyopathy (DCM) is achieved using a variety of two-dimensional and Doppler echocardiographic techniques. More recently, the availability of tissue Doppler imaging (TDI) has raised the potential for development of new ways of more accurately identifying a disease phenotype. Nevertheless, TDI has not been universally adapted to veterinary clinical cardiology primarily because of the lack of information on its utility in diagnosis. We assessed the application of timing of left heart base descent using TDI in the identification of differences between DCM and normal dogs. The times from the onset of the QRS complex on a simultaneously recorded electrocardiograph to the onset (Q--S'), peak (Q--peak S'), and end (Q--end S') of the systolic velocity peak were measured in the interventricular septum (IVS) and the left ventricular free wall. The duration of S' was also calculated. The Q--S' (FW), Q--end S' (FW), and duration S' (FW) were correlated with ejection fraction in the diseased group (P canine DCM and identifies new TDI parameters that can be added to the range of Doppler and echocardiographic parameters used for detecting myocardial failure in the dog.

  9. A human pericardium biopolymeric scaffold for autologous heart valve tissue engineering: cellular and extracellular matrix structure and biomechanical properties in comparison with a normal aortic heart valve.

    Science.gov (United States)

    Straka, Frantisek; Schornik, David; Masin, Jaroslav; Filova, Elena; Mirejovsky, Tomas; Burdikova, Zuzana; Svindrych, Zdenek; Chlup, Hynek; Horny, Lukas; Daniel, Matej; Machac, Jiri; Skibová, Jelena; Pirk, Jan; Bacakova, Lucie

    2018-04-01

    The objective of our study was to compare the cellular and extracellular matrix (ECM) structure and the biomechanical properties of human pericardium (HP) with the normal human aortic heart valve (NAV). HP tissues (from 12 patients) and NAV samples (from 5 patients) were harvested during heart surgery. The main cells in HP were pericardial interstitial cells, which are fibroblast-like cells of mesenchymal origin similar to the valvular interstitial cells in NAV tissue. The ECM of HP had a statistically significantly (p structures of the two tissues, the dense part of fibrous HP (49 ± 2%) and the lamina fibrosa of NAV (47 ± 4%), was similar. In both tissues, the secant elastic modulus (Es) was significantly lower in the transversal direction (p structure and has the biomechanical properties required for a tissue from which an autologous heart valve replacement may be constructed.

  10. Factors influencing circadian rhythms in acetaminophen lethality.

    Science.gov (United States)

    Schnell, R C; Bozigian, H P; Davies, M H; Merrick, B A; Park, K S; McMillan, D A

    1984-01-01

    Experiments were conducted to examine the effects of changes in lighting schedules and food consumption on circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice. Under a normal lighting schedule (light: 06.00-18.00 h), male mice exhibited a circadian rhythm in acetaminophen lethality (peak: 18.00 h; nadir: 06.00, 10.00 h) and an inverse rhythm in hepatic glutathione concentrations (peak: 06.00, 10.00 h; nadir: 18.00 h). Under a reversed lighting schedule (light: 18.00-06.00 h) the glutathione rhythm was reversed and the rhythm in acetaminophen lethality was altered showing greater sensitivity to the drug. Under continuous light, there was a shift in the acetaminophen lethality and the hepatic glutathione rhythms. Under continuous dark, both rhythms were abolished. Under a normal lighting regimen, hepatic glutathione levels were closely correlated with food consumption; i.e., both were increased during the dark phase and decreased during the light phase. Fasting the mice for 12 h abolished the rhythms in acetaminophen lethality and hepatic glutathione levels; moreover, the lethality was increased and the hepatic glutathione levels were decreased. These experiments show that both lighting schedules and feeding can alter the circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice.

  11. Fluoxetine normalizes disrupted light-induced entrainment, fragmented ultradian rhythms and altered hippocampal clock gene expression in an animal model of high trait anxiety- and depression-related behavior.

    Science.gov (United States)

    Schaufler, Jörg; Ronovsky, Marianne; Savalli, Giorgia; Cabatic, Maureen; Sartori, Simone B; Singewald, Nicolas; Pollak, Daniela D

    2016-01-01

    Disturbances of circadian rhythms are a key symptom of mood and anxiety disorders. Selective serotonin reuptake inhibitors (SSRIs) - commonly used antidepressant drugs - also modulate aspects of circadian rhythmicity. However, their potential to restore circadian disturbances in depression remains to be investigated. The effects of the SSRI fluoxetine on genetically based, depression-related circadian disruptions at the behavioral and molecular level were examined using mice selectively bred for high anxiety-related and co-segregating depression-like behavior (HAB) and normal anxiety/depression behavior mice (NAB). The length of the circadian period was increased in fluoxetine-treated HAB as compared to NAB mice while the number of activity bouts and light-induced entrainment were comparable. No difference in hippocampal Cry2 expression, previously reported to be dysbalanced in untreated HAB mice, was observed, while Per2 and Per3 mRNA levels were higher in HAB mice under fluoxetine treatment. The present findings provide evidence that fluoxetine treatment normalizes disrupted circadian locomotor activity and clock gene expression in a genetic mouse model of high trait anxiety and depression. An interaction between the molecular mechanisms mediating the antidepressant response to fluoxetine and the endogenous regulation of circadian rhythms in genetically based mood and anxiety disorders is proposed.

  12. Heart Failure Increases the Risk of Adverse Renal Outcomes in Patients With Normal Kidney Function.

    Science.gov (United States)

    George, Lekha K; Koshy, Santhosh K G; Molnar, Miklos Z; Thomas, Fridtjof; Lu, Jun L; Kalantar-Zadeh, Kamyar; Kovesdy, Csaba P

    2017-08-01

    Heart failure (HF) is associated with poor cardiac outcomes and mortality. It is not known whether HF leads to poor renal outcomes in patients with normal kidney function. We hypothesized that HF is associated with worse long-term renal outcomes. Among 3 570 865 US veterans with estimated glomerular filtration rate (eGFR) ≥60 mL min -1 1.73 m -2 during October 1, 2004 to September 30, 2006, we identified 156 743 with an International Classification of Diseases , Ninth Revision , diagnosis of HF. We examined the association of HF with incident chronic kidney disease (CKD), the composite of incident CKD or mortality, and rapid rate of eGFR decline (slopes steeper than -5 mL min -1 1.73 m -2 y -1 ) using Cox proportional hazard analyses and logistic regression. Adjustments were made for various confounders. The mean±standard deviation baseline age and eGFR of HF patients were 68±11 years and 78±14 mL min -1 1.73 m -2 and in patients without HF were 59±14 years and 84±16 mL min -1 1.73 m -2 , respectively. HF patients had higher prevalence of hypertension, diabetes mellitus, cardiac, peripheral vascular and chronic lung diseases, stroke, and dementia. Incidence of CKD was 69.0/1000 patient-years in HF patients versus 14.5/1000 patient-years in patients without HF, and 22% of patients with HF had rapid decline in eGFR compared with 8.5% in patients without HF. HF patients had a 2.12-, 2.06-, and 2.13-fold higher multivariable-adjusted risk of incident CKD, composite of CKD or mortality, and rapid eGFR decline, respectively. HF is associated with significantly higher risk of incident CKD, incident CKD or mortality, and rapid eGFR decline. Early diagnosis and management of HF could help reduce the risk of long-term renal complications. © 2017 American Heart Association, Inc.

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

    Science.gov (United States)

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

    2018-03-01

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

  14. Heart rate, heart rate variability, and arrhythmias in dogs with myxomatous mitral valve disease

    DEFF Research Database (Denmark)

    Rasmussen, Caroline Elisabeth; Falk, Bo Torkel; Zois, Nora Elisabeth

    2012-01-01

    Autonomic modulation of heart rhythm is thought to influence the pathophysiology of myxomatous mitral valve disease (MMVD).......Autonomic modulation of heart rhythm is thought to influence the pathophysiology of myxomatous mitral valve disease (MMVD)....

  15. Circadian rhythm disruption was observed in hand, foot, and mouth disease patients.

    Science.gov (United States)

    Zhu, Yu; Jiang, Zhou; Xiao, Guoguang; Cheng, Suting; Wen, Yang; Wan, Chaomin

    2015-03-01

    Hand, foot, and mouth disease (HFMD) with central nerve system complications may rapidly progress to fulminated cardiorespiratory failure, with higher mortality and worse prognosis. It has been reported that circadian rhythms of heart rate (HR) and respiratory rate are useful in predicting prognosis of severe cardiovascular and neurological diseases. The present study aims to investigate the characteristics of the circadian rhythms of HR, respiratory rate, and temperature in HFMD patients with neurological complications. Hospitalized HFMD patients including 33 common cases (common group), 61 severe cases (severe group), and 9 critical cases (critical group) were contrasted retrospectively. Their HR, respiratory rate, and temperatures were measured every 4 hours during the first 48-hour in the hospital. Data were analyzed with the least-squares fit of a 24-hour cosine function by the single cosinor and population-mean cosinor method. Results of population-mean cosinor analysis demonstrated that the circadian rhythm of HR, respiratory rate, and temperature was present in the common and severe group, but absent in the critical group. The midline-estimating statistic of rhythm (MESOR) (P = 0.016) and acrophase (P circadian characteristics of HR among 3 groups. Compared with the common group, the MESOR of temperature and respiratory rate was significantly higher, and acrophase of temperature and respiratory rate was 2 hours ahead in the severe group, critical HFMD patients lost their population-circadian rhythm of temperature, HR, and respiratory rate. The high values of temperature and respiratory rate for the common group were concentrated between 3 and 9 PM, whereas those for the severe group were more dispersive. And the high values for the critical group were equally distributed in 24 hours of the day. Circadian rhythm of patients' temperature in the common group was the same as the normal rhythm of human body temperature. Circadian rhythm of patients

  16. In vitro cultured progenitors and precursors of cardiac cell lineages from human normal and post-ischemic hearts

    Directory of Open Access Journals (Sweden)

    F Di Meglio

    2009-08-01

    Full Text Available The demonstration of the presence of dividing primitive cells in damaged hearts has sparked increased interest about myocardium regenerative processes. We examined the rate and the differentiation of in vitro cultured resident cardiac primitive cells obtained from pathological and normal human hearts in order to evaluate the activation of progenitors and precursors of cardiac cell lineages in post-ischemic human hearts. The precursors and progenitors of cardiomyocyte, smooth muscle and endothelial lineage were identified by immunocytochemistry and the expression of characteristic markers was studied by western blot and RT-PCR. The amount of proteins characteristic for cardiac cells (a-SA and MHC, VEGFR-2 and FVIII, SMA for the precursors of cardiomyocytes, endothelial and smooth muscle cells, respectively inclines toward an increase in both a-SA and MHC. The increased levels of FVIII and VEGFR2 are statistically significant, suggesting an important re-activation of neoangiogenesis. At the same time, the augmented expression of mRNA for Nkx 2.5, the trascriptional factor for cardiomyocyte differentiation, confirms the persistence of differentiative processes in terminally injured hearts. Our study would appear to confirm the activation of human heart regeneration potential in pathological conditions and the ability of its primitive cells to maintain their proliferative capability in vitro. The cardiac cell isolation method we used could be useful in the future for studying modifications to the microenvironment that positively influence cardiac primitive cell differentiation or inhibit, or retard, the pathological remodeling and functional degradation of the heart.

  17. Patient experiences of recovery after heart valve replacement: suffering weakness, struggling to resume normality

    DEFF Research Database (Denmark)

    Kikkenborg Berg, Selina; Zwisler, Ann-Dorthe; Pedersen, Birthe D.

    2013-01-01

    Heart valve disease is becoming a public health problem due to increasing life expectancy and new treatment methods. Patients are at risk of developing depression, anxiety or post-traumatic stress disorder after heart valve surgery. To better plan proper care, describing and understanding patients...

  18. Sustained Accelerated Idioventricular Rhythm in a Centrifuge-Simulated Suborbital Spaceflight.

    Science.gov (United States)

    Suresh, Rahul; Blue, Rebecca S; Mathers, Charles; Castleberry, Tarah L; Vanderploeg, James M

    2017-08-01

    Hypergravitational exposures during human centrifugation are known to provoke dysrhythmias, including sinus dysrhythmias/tachycardias, premature atrial/ventricular contractions, and even atrial fibrillations or flutter patterns. However, events are generally short-lived and resolve rapidly after cessation of acceleration. This case report describes a prolonged ectopic ventricular rhythm in response to high G exposure. A previously healthy 30-yr-old man voluntarily participated in centrifuge trials as a part of a larger study, experiencing a total of 7 centrifuge runs over 48 h. Day 1 consisted of two +Gz runs (peak +3.5 Gz, run 2) and two +Gx runs (peak +6.0 Gx, run 4). Day 2 consisted of three runs approximating suborbital spaceflight profiles (combined +Gx and +Gz). Hemodynamic data collected included blood pressure, heart rate, and continuous three-lead electrocardiogram. Following the final acceleration exposure of the last Day 2 run (peak +4.5 Gx and +4.0 Gz combined, resultant +6.0 G), during a period of idle resting centrifuge activity (resultant vector +1.4 G), the subject demonstrated a marked change in his three-lead electrocardiogram from normal sinus rhythm to a wide-complex ectopic ventricular rhythm at a rate of 91-95 bpm, consistent with an accelerated idioventricular rhythm (AIVR). This rhythm was sustained for 2 m, 24 s before reversion to normal sinus. The subject reported no adverse symptoms during this time. While prolonged, the dysrhythmia was asymptomatic and self-limited. AIVR is likely a physiological response to acceleration and can be managed conservatively. Vigilance is needed to ensure that AIVR is correctly distinguished from other, malignant rhythms to avoid inappropriate treatment and negative operational impacts.Suresh R, Blue RS, Mathers C, Castleberry TL, Vanderploeg JM. Sustained accelerated idioventricular rhythm in a centrifuge-simulated suborbital spaceflight. Aerosp Med Hum Perform. 2017; 88(8):789-793.

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

    Science.gov (United States)

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

    2017-04-13

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

  20. Acromegaly with Normal Insulin-Like Growth Factor-1 Levels and Congestive Heart Failure as the First Clinical Manifestation

    Directory of Open Access Journals (Sweden)

    Hyae Min Lee

    2015-09-01

    Full Text Available The leading cause of morbidity and mortality in patients with acromegaly is cardiovascular complications. Myocardial exposure to excessive growth hormone can cause ventricular hypertrophy, hypertension, arrhythmia, and diastolic dysfunction. However, congestive heart failure as a result of systolic dysfunction is observed only rarely in patients with acromegaly. Most cases of acromegaly exhibit high levels of serum insulin-like growth factor-1 (IGF-1. Acromegaly with normal IGF-1 levels is rare and difficult to diagnose. Here, we report a rare case of an acromegalic patient whose first clinical manifestation was severe congestive heart failure, despite normal IGF-1 levels. We diagnosed acromegaly using a glucose-loading growth hormone suppression test. Cardiac function and myocardial hypertrophy improved 6 months after transsphenoidal resection of a pituitary adenoma.

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

    NARCIS (Netherlands)

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

    2008-01-01

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

  2. Hearts of dystonia musculorum mice display normal morphological and histological features but show signs of cardiac stress.

    Directory of Open Access Journals (Sweden)

    Justin G Boyer

    2010-03-01

    Full Text Available Dystonin is a giant cytoskeletal protein belonging to the plakin protein family and is believed to crosslink the major filament systems in contractile cells. Previous work has demonstrated skeletal muscle defects in dystonin-deficient dystonia musculorum (dt mice. In this study, we show that the dystonin muscle isoform is localized at the Z-disc, the H zone, the sarcolemma and intercalated discs in cardiac tissue. Based on this localization pattern, we tested whether dystonin-deficiency leads to structural defects in cardiac muscle. Desmin intermediate filament, microfilament, and microtubule subcellular organization appeared normal in dt hearts. Nevertheless, increased transcript levels of atrial natriuretic factor (ANF, 66% beta-myosin heavy chain (beta-MHC, 95% and decreased levels of sarcoplasmic reticulum calcium pump isoform 2A (SERCA2a, 26%, all signs of cardiac muscle stress, were noted in dt hearts. Hearts from two-week old dt mice were assessed for the presence of morphological and histological alterations. Heart to body weight ratios as well as left ventricular wall thickness and left chamber volume measurements were similar between dt and wild-type control mice. Hearts from dt mice also displayed no signs of fibrosis or calcification. Taken together, our data provide new insights into the intricate structure of the sarcomere by situating dystonin in cardiac muscle fibers and suggest that dystonin does not significantly influence the structural organization of cardiac muscle fibers during early postnatal development.

  3. High self-perceived stress and many stressors, but normal diurnal cortisol rhythm, in adults with ADHD (attention-deficit/hyperactivity disorder).

    Science.gov (United States)

    Hirvikoski, Tatja; Lindholm, Torun; Nordenström, Anna; Nordström, Anna-Lena; Lajic, Svetlana

    2009-03-01

    Attention-deficit/hyperactivity disorder (ADHD) in adults is associated with significant impairment in many life activities and may thus increase the risk of chronic stress in everyday life. We compared adults with a DSM-IV ADHD diagnosis (n=28) with healthy controls (n=28) regarding subjective stress and amounts of stressors in everyday life, diurnal salivary cortisol in the everyday environment and salivary cortisol before and after cognitive stress in a laboratory setting. The association between cortisol concentrations and impulsivity was also investigated. Consistent with assumptions, individuals with ADHD reported significantly more self-perceived stress than controls, and subjective stress correlated with the amount of stressors in everyday life. The two groups were comparable with respect to overall diurnal cortisol levels and rhythm, as well as in pre- and post-stress cortisol concentrations. Post-stress cortisol (but not baseline cortisol) concentration was positively correlated with impulsivity. The group with high post-stress cortisol also reported more symptoms of depression and anxiety, as well as self-perceived stress and stressors in every-day life. The diagnosis of ADHD significantly increased the risk of belonging to the group with high post-stress cortisol levels. The results in this study warrant a focus not only on the primary diagnosis of ADHD, but also calls for a broader assessment of stressors and subjective stress in everyday life, as well as support comprising stress management and coping skills.

  4. Visible Battle Rhythm

    National Research Council Canada - National Science Library

    Cort, Brian; Bouchard, Alain; Gouin, Denis; Proulx, Pascale; Wright, William

    2006-01-01

    .... Visual Battle Rhythm (VBR) is a software prototype which updates the battle rhythm process with modern technology and careful information design to improve the synchronization, situational awareness and decision making ability of commanders...

  5. Quantitative assessment of thallium myocardial washout rate: Importance of peak heart rate and lung thallium uptake in defining normal values

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Kozuka, Takahiro; Saito, Muneyasu; Sumiyoshi, Tetsuya; National Cardiovascular Center, Suita, Osaka

    1987-01-01

    Traditionally, the results of exercise thallium scintigraphy were interpreted by transient defect analysis using initial and delayed images. Recently, washout rate analysis has been used for the relative quantification of exercise thallium scintigraphy. A diffuse slow washout from all myocardial regions has been defined as the indicator of extensive coronary artery disease. However, slow washout has occasionally been observed in normal cases and in healthy myocardial segments which are not supplied by a stenosed artery in patients with single or double vessel disease. We evaluate the factors influencing washout rate in 100 normal patients and 63 patients with angina pectoris (33 cases of single vessel disease and 30 cases of double vessel disease). The washout rates were calculated using circumferential profile analysis. In normal patients, washout rate was closely related to peak heart rate (r=0.72) and inversely related to lung thallium uptake (r=-0.56). A diffuse slow washout was observed in seven (7%) of 100 normal patients, six (18%) of 33 cases of single vessel disease and eight (24%) of 30 cases of double vessel disease. The patients with diffuse slow washout showed significantly higher lung thallium uptake values and lower peak heart rates than those without diffuse slow washout (P<0.01). Thus, this false positive slow washout should be considered in the interpretation of quantitative exercise thallium scintigraphy. (orig.)

  6. Physiological roles of the transient outward current Ito in normal and diseased hearts

    DEFF Research Database (Denmark)

    Cordeiro, Jonathan M.; Callø, Kirstine; Aschar-Sobbi, Roozbeh

    2016-01-01

    The Ca2+-independent transient outward K+ current (Ito) plays a critical role in underlying phase 1 of repolarization of the cardiac action potential and, as a result, is central to modulating excitation-contraction coupling and propensity for arrhythmia. Additionally, Ito and its molecular...... potential and the mechanisms by which Ito modulates excitation-contraction coupling. We also describe the effects of mutations in the subunits constituting the Ito channel as well as the role of Ito in the failing myocardium. Finally, we review pharmacological modulation of Ito and discuss the evidence...... constituents are consistently reduced in cardiac hypertrophy and heart failure. In this review, we discuss the physiological role of Ito as well as the molecular basis of this current in human and canine hearts, in which Ito has been thoroughly studied. In particular, we discuss the role of Ito in the action...

  7. Atrial and Ventricular Electrocardiographic Dromotropic Disturbances in Down Syndrome Patients with Structurally Normal Heart: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Yazdan Ghandi

    2018-03-01

    Full Text Available Background: We designed a cross-sectional study to determine electrocardiographic disorders in Down syndrome patients with congenitally normal hearts in a bid to predict fatal cardiac arrhythmia in the future. Materials and Methods: We investigated 60 children with DS without congenital abnormal hearts. Sixty healthy juveniles were also included in the study as a control group. Physical examination, electrocardiography, and echocardiography were performed in all subjects. Corrected QT interval (QTc was measured according to Bazett’s formula. Results: Patients with DS consisted of 32 males (53.33%, and 28 females (46.66%, aged 6–13 (9.21 ± 6.24 years old. Healthy subjects comprised 31 males (51.66%, and 29 females (48.33% with a mean age of 9.15 ± 5.01. The two groups were significantly different in terms of heart rate (P=0.006, maximum P-wave duration (P=0.001, and P-wave dispersion (PWd, P=0.0001. There was no statistically significant difference regarding minimum P-wave duration (P=0.176. The patients with DS had a greater maximum QTc interval, QT dispersion, and corrected QT interval dispersion (QTc-d than the healthy control subjects (P=0.001. However, there was no difference in maximum QT interval and minimum QTc interval between the two groups (P=0.67 and P=0.553, respectively. A positive correlation was found between age, heart rate, and all electrocardiographic variables. Conclusion: All DS patients, even in the absence of concomitant congenital heart disease should be followed up carefully by electrocardiography, looking for increased PWd and QTc-d to detect predisposed cases to arrhythmia.

  8. The normal heart - Part I. The cardiac outline and chamber anatomy

    International Nuclear Information System (INIS)

    Walker, J.

    1985-01-01

    The heart is the most open and the most secret object in all radiology. Surrounded by alveolar air (its natural contrast) its outline dominates the chest X-ray. The lung vessels, responding to any change in function, are openly displayed, but within the heart borders the X-ray shadow is obscure and its parts invisible; moreover its vital purpose, movement, is not seen. This hollow muscular organ is conical, its apex points downwards, forwards and to the left at 60 0 to the midline. It is roughly 12 cm in length and weighs about 350 g. The main vessels enter and leave at the base posteriorly. Its apex is free within the serous cavity of the pericardium but its base is fixed by vessels and by the pericardial reflexions which surround them. The embryonic dorsal mesopericardium between arteries and veins breaks down to give the transverse sinus which frees the heart posteriorly, and the reflexions around the pulmonary veins form a blind sac, the oblique sinus, which opens to the left. All is enclosed by fibrous pericardium and occupies the anterior mediastinum at the level of the 6th-9th dorsal vertebrae from which it is separated by the oesophagus, aorta and spinal muscles. It rests on the central tendon of the diaphragm and laterally the right and left lungs envelop it over more than two thirds of its surface

  9. Is "treat your child normally" helpful advice for parents of survivors of treatment of hypoplastic left heart syndrome?

    Science.gov (United States)

    Rempel, Gwen R; Harrison, Margaret J; Williamson, Deanna L

    2009-04-01

    Developing technology affords children with complex congenitally malformed hearts a chance for survival. Parents gratefully pursue life-saving options on behalf of their children, despite the risks to the life of their child, and uncertainty about outcomes. Little is known about how mothers and fathers experience parenting a child whose new state as a survivor may include less than optimal developmental sequels. Our study involved multiple interactive interviews with 9 mothers and 7 fathers of infants and preschool children with hypoplastic left heart syndrome who had survived the Norwood surgical approach. Qualitative methodology included grounded theory methods of simultaneous collection and analysis of data, and we used open and selective coding of transcribed interviews. Parents used normalization in the context of uncertainty regarding the ongoing survival of their child. Parents described their underweight children as being on their own growth curve, and viewed their developmental progress, however delayed, as reason for celebration, as they had been prepared for their child to die. There is growing evidence that children with congenitally malformed hearts who require surgical intervention during the first year of life may experience developmental delay. The use of normalization by their parents may be effective in decreasing their worry regarding the uncertain future faced by their child, but may negatively affect the developmental progress of the child if they do not seek resources to assist development. Advice from paediatric specialists for parents to view their children as normal needs to be balanced with assistance for parents to access services to support optimal growth and development of their child.

  10. Effect of sinus rhythm restoration on plasma brain natriuretic peptide (BNP) levels in patients with atrial fibrillation

    International Nuclear Information System (INIS)

    An Liping; Jin Zhexiu; Zhang Chengqiu

    2005-01-01

    Objective: To study the changes of plasma brain natriuretic peptide (BNP) levels before and after sinus rhythm restoration in patients with paroxysmal or persistent atrial fibrillation (AF) but normal left ventricle function and to explore the role of BNP in AF. Methods: Plasma BNP levels were measured with RIA in 68 patients and 34 controls. Results: Twenty four hours after successful cardioversion, plasma BNP levels decreased significantly in all the patients. The 30 patients with paroxysmal atrial fibrillation were all restored to sinus rhythm and levels of plasma BNP dropped from 96±42pg/ml to 28 ±21pg/ml. Of the 38 patients with persistent atrial fibrillation, 28 of them were restored to sinus rhythm, in whom levels of plasma BNP dropped from 73±38pg/ml to 38±25pg/ml. Conclusion: The presence of AF should be taken into consideration when interpreting plasma BNP levels in patients with heart disease. (authors)

  11. An artificial vector model for generating abnormal electrocardiographic rhythms

    International Nuclear Information System (INIS)

    Clifford, Gari D; Nemati, Shamim; Sameni, Reza

    2010-01-01

    We present generalizations of our previously published artificial models for generating multi-channel ECG to provide simulations of abnormal cardiac rhythms. Using a three-dimensional vectorcardiogram (VCG) formulation, we generate the normal cardiac dipole for a patient using a sum of Gaussian kernels, fitted to real VCG recordings. Abnormal beats are specified either as perturbations to the normal dipole or as new dipole trajectories. Switching between normal and abnormal beat types is achieved using a first-order Markov chain. Probability transitions can be learned from real data or modeled by coupling to heart rate and sympathovagal balance. Natural morphology changes from beat-to-beat are incorporated by varying the angular frequency of the dipole as a function of the inter-beat (RR) interval. The RR interval time series is generated using our previously described model whereby time- and frequency-domain heart rate (HR) and heart rate variability characteristics can be specified. QT-HR hysteresis is simulated by coupling the Gaussian kernels associated with the T-wave in the model with a nonlinear factor related to the local HR (determined from the last n RR intervals). Morphology changes due to respiration are simulated by introducing a rotation matrix couple to the respiratory frequency. We demonstrate an example of the use of this model by simulating HR-dependent T-wave alternans (TWA) with and without phase-switching due to ectopy. Application of our model also reveals previously unreported effects of common TWA estimation methods

  12. Circadian rhythms and reproduction.

    Science.gov (United States)

    Boden, Michael J; Kennaway, David J

    2006-09-01

    There is a growing recognition that the circadian timing system, in particular recently discovered clock genes, plays a major role in a wide range of physiological systems. Microarray studies, for example, have shown that the expression of hundreds of genes changes many fold in the suprachiasmatic nucleus, liver heart and kidney. In this review, we discuss the role of circadian rhythmicity in the control of reproductive function in animals and humans. Circadian rhythms and clock genes appear to be involved in optimal reproductive performance, but there are sufficient redundancies in their function that many of the knockout mice produced do not show overt reproductive failure. Furthermore, important strain differences have emerged from the studies especially between the various Clock (Circadian Locomotor Output Cycle Kaput) mutant strains. Nevertheless, there is emerging evidence that the primary clock genes, Clock and Bmal1 (Brain and Muscle ARNT-like protein 1, also known as Mop3), strongly influence reproductive competency. The extent to which the circadian timing system affects human reproductive performance is not known, in part, because many of the appropriate studies have not been done. With the role of Clock and Bmal1 in fertility becoming clearer, it may be time to pursue the effect of polymorphisms in these genes in relation to the various types of infertility in humans.

  13. Markets, Bodies, Rhythms

    DEFF Research Database (Denmark)

    Borch, Christian; Bondo Hansen, Kristian; Lange, Ann-Christina

    2015-01-01

    to respond to a widely perceived problem, namely that market rhythms might be contagious and that some form of separation of bodily and market rhythms might therefore be needed. Finally, we show how current high-frequency trading, despite being purely algorithmic, does not render the traders' bodies......This article explores the relationship between bodily rhythms and market rhythms in two distinctly different financial market configurations, namely the open-outcry pit (prevalent especially in the early 20th century) and present-day high-frequency trading. Drawing on Henri Lefebvre......'s rhythmanalysis, we show how traders seek to calibrate their bodily rhythms to those of the market. We argue that, in the case of early-20th-century open-outcry trading pits, traders tried to enact a total merger of bodily and market rhythms. We also demonstrate how, in the 1920s and '30s, market observers began...

  14. Circadian Rhythm Sleep Disorders

    Directory of Open Access Journals (Sweden)

    Erhan Akinci

    2016-06-01

    Full Text Available The circadian rhythm sleep disorders define the clinical conditions where sleep and ndash;wake rhythm is disrupted despite optimum environmental and social conditions. They occur as a result of the changes in endogenous circadian hours or non-compatibility of environmental factors or social life with endogenous circadian rhythm. The sleep and ndash;wake rhythm is disrupted continuously or in repeating phases depending on lack of balance between internal and external cycles. This condition leads to functional impairments which cause insomnia, excessive sleepiness or both in people. Application of detailed sleep anamnesis and sleep diary with actigraphy record, if possible, will be sufficient for diagnosis. The treatment aims to align endogenous circadian rhythm with environmental conditions. The purpose of this article is to review pathology, clinical characteristics, diagnosis and treatment of circadian rhythm disorder. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(2: 178-189

  15. Study of Regulatory Mechanisms of Activity of Cardiovascular System by Method of Mathematical Analysis of Heart Rhythm in Workers of Chemical Manufactures

    Science.gov (United States)

    Dyachkova, T. V.; Berseneva, I. A.; Zavaltseva, O. A.; Mishina, O. S.

    2018-01-01

    The article presents the results of the study of heart rate variability indices of workers engaged in the production of phenol-formaldehyde plastics and plastics at the «Karbodin» plant. 112 people aged from 20 to 50 years were studied: control group-workers with experience up to 1 year, practically healthy (n = 30), 1 group-workers with work experience up to 5 years (n = 40), 2 group workers with work experience from 5 to 10 years (n = 42). As a result of the study, violations of the functioning of the heart regulation system were revealed, depending on the length of employment. The effectiveness of the method for studying the regulation of the physiological functions of the circulatory system as well as the early diagnosis of occupational pathology has been established.

  16. Contribution of the Arterial System and the Heart to Blood Pressure during Normal Aging - A Simulation Study.

    Science.gov (United States)

    Maksuti, Elira; Westerhof, Nico; Westerhof, Berend E; Broomé, Michael; Stergiopulos, Nikos

    2016-01-01

    During aging, systolic blood pressure continuously increases over time, whereas diastolic pressure first increases and then slightly decreases after middle age. These pressure changes are usually explained by changes of the arterial system alone (increase in arterial stiffness and vascular resistance). However, we hypothesise that the heart contributes to the age-related blood pressure progression as well. In the present study we quantified the blood pressure changes in normal aging by using a Windkessel model for the arterial system and the time-varying elastance model for the heart, and compared the simulation results with data from the Framingham Heart Study. Parameters representing arterial changes (resistance and stiffness) during aging were based on literature values, whereas parameters representing cardiac changes were computed through physiological rules (compensated hypertrophy and preservation of end-diastolic volume). When taking into account arterial changes only, the systolic and diastolic pressure did not agree well with the population data. Between 20 and 80 years, systolic pressure increased from 100 to 122 mmHg, and diastolic pressure decreased from 76 to 55 mmHg. When taking cardiac adaptations into account as well, systolic and diastolic pressure increased from 100 to 151 mmHg and decreased from 76 to 69 mmHg, respectively. Our results show that not only the arterial system, but also the heart, contributes to the changes in blood pressure during aging. The changes in arterial properties initiate a systolic pressure increase, which in turn initiates a cardiac remodelling process that further augments systolic pressure and mitigates the decrease in diastolic pressure.

  17. Thyroid Function Within the Normal Range and Risk of Coronary Heart Disease

    DEFF Research Database (Denmark)

    Åsvold, Bjørn O; Vatten, Lars J; Bjøro, Trine

    2015-01-01

    documented, but conflicting evidence suggests that thyrotropin levels in the upper part of the reference range may be associated with an increased risk of coronary heart disease (CHD). OBJECTIVE: To assess the association between differences in thyroid function within the reference range and CHD risk. DESIGN...... known thyroid or cardiovascular disease at baseline. EXPOSURES: Thyroid function as expressed by serum thyrotropin levels at baseline. MAIN OUTCOMES AND MEASURES: Hazard ratios (HRs) of CHD mortality and CHD events according to thyrotropin levels after adjustment for age, sex, and smoking status....... This finding suggests that differences in thyroid function within the population reference range do not influence the risk of CHD. Increased CHD risk does not appear to be a reason for lowering the upper thyrotropin reference limit....

  18. Hyperventilation and circadian rhythm of the electrical stability of rat myocardium

    Directory of Open Access Journals (Sweden)

    Svorc P

    2013-08-01

    Full Text Available Pavol Svorc,1,2 Alexander Marossy,1 Pavol Svorc Jr2 1Department of Physiology, Medical Faculty, Safarik University, Kosice, Slovak Republic; 2Department of Physiology, Medical Faculty, Ostrava University, Ostrava, Czech Republic Objective: Respiratory alkalosis is an extremely common and complicated problem affecting virtually every organ system where the etiologies may be related to pulmonary or cardiovascular disorders. However, there are only few works describing daytime experiments or synchronization of animals to the external environmental periodicity. The aim of the study is to describe the circadian rhythm of the electrical stability of the heart under hyperventilatory conditions. Methods: Circadian rhythms of the electrical stability of the heart, measured by ventricular arrhythmia threshold ([VAT] measurement in 3 hour intervals, were followed during normal artificial ventilation (40 breaths/minute, tidal volume = 1 mL/100 g; n = 17 and hyperventilation (80 breaths/minute, tidal volume = 2 mL/100 g; n = 7 in pentobarbital (40 mg/kg administered intraperitoneally anesthetized female Wistar rats, after 4 week adaptation on the light/dark regime of 12 hour light/12 hour dark (40%–60% humidity, room temperature of 24°C in cages, two animals/cage with access to food and water ad libitum, with the dark period from 18.00h to 06.00h for 4 weeks. Results: The 24 hour course of the VAT showed the highest susceptibility of the rat ventricular myocardium to arrhythmias between 12.00h and 15.00h, and highest resistance between 19.20h and 00.28h (acrophase −338° in time at 22.53h with confidence intervals −2,880° to −70°, under normoxic conditions. Mesor was 2.59 ± 0.53 mA and amplitude 0.33 ± 0.11 mA. Hyperventilation increased the VAT at each interval of the measurement, but did not change the character of its circadian rhythm. Acrophase was on −40° (02.40h, mesor was increased (2.91 mA, and amplitude was decreased (0.13 m

  19. Circadian rhythm asynchrony in man during hypokinesis.

    Science.gov (United States)

    Winget, C. M.; Vernikos-Danellis, J.; Cronin, S. E.; Leach, C. S.; Rambaut, P. C.; Mack, P. B.

    1972-01-01

    Posture and exercise were investigated as synchronizers of certain physiologic rhythms in eight healthy male subjects in a defined environment. Four subjects exercised during bed rest. Body temperature (BT), heart rate, plasma thyroid hormone, and plasma steroid data were obtained from the subjects for a 6-day ambulatory equilibration period before bed rest, 56 days of bed rest, and a 10-day recovery period after bed rest. The results indicate that the mechanism regulating the circadian rhythmicity of the cardiovascular system is rigorously controlled and independent of the endocrine system, while the BT rhythm is more closely aligned to the endocrine system.

  20. Circadian Rhythm Control: Neurophysiological Investigations

    Science.gov (United States)

    Glotzbach, S. F.

    1985-01-01

    The suprachiasmatic nucleus (SCN) was implicated as a primary component in central nervous system mechanisms governing circadian rhythms. Disruption of the normal synchronization of temperature, activity, and other rhythms is detrimental to health. Sleep wake disorders, decreases in vigilance and performance, and certain affective disorders may result from or be exacerbated by such desynchronization. To study the basic neurophysiological mechanisms involved in entrainment of circadian systems by the environment, Parylene-coated, etched microwire electrode bundles were used to record extracellular action potentials from the small somata of the SCN and neighboring hypothalamic nuclei in unanesthetized, behaving animals. Male Wistar rats were anesthetized and chronically prepared with EEG ane EMG electrodes in addition to a moveable microdrive assembly. The majority of cells had firing rates 10 Hz and distinct populations of cells which had either the highest firing rate or lowest firing rate during sleep were seen.

  1. Bleeding risk assessment and management in atrial fibrillation patients. Executive Summary of a Position Document from the European Heart Rhythm Association [EHRA], endorsed by the European Society of Cardiology [ESC] Working Group on Thrombosis.

    Science.gov (United States)

    Lip, Gregory Y H; Andreotti, Felicita; Fauchier, Laurent; Huber, Kurt; Hylek, Elaine; Knight, Eve; Lane, Deirdre; Levi, Marcel; Marín, Francisco; Palareti, Gualtiero; Kirchhof, Paulus

    2011-12-01

    In this executive summary of a Consensus Document from the European Heart Rhythm Association, endorsed by the European Society of Cardiology Working Group on Thrombosis, we comprehensively review the published evidence and propose a consensus on bleeding risk assessments in atrial fibrillation (AF) patients. The main aim of the document was to summarise 'best practice' in dealing with bleeding risk in AF patients when approaching antithrombotic therapy, by addressing the epidemiology and size of the problem, and review established bleeding risk factors. We also summarise definitions of bleeding in the published literature. Patient values and preferences balancing the risk of bleeding against thromboembolism as well as the prognostic implications of bleeding are reviewed. We also provide an overview of published bleeding risk stratification and bleeding risk schema. Brief discussion of special situations (e.g. periablation, peri-devices such as implantable cardioverter defibrillators [ICD] or pacemakers, presentation with acute coronary syndromes and/or requiring percutanous coronary interventions/stents and bridging therapy) is made, as well as a discussion of the prevention of bleeds and managing bleeding complications. Finally, this document puts forwards consensus statements that may help to define evidence gaps and assist in everyday clinical practice.

  2. Cardiopulmonary determinants of functional capacity in patients with chronic heart failure compared with normals.

    Science.gov (United States)

    Meyer, K; Westbrook, S; Schwaibold, M; Hajric, R; Lehmann, M; Roskamm, H

    1996-12-01

    Patients with chronic heart failure (CHF) are characterized by abnormal gas exchange and ventilatory responses to exercise. This study compares variables obtained from cardiopulmonary exercise testing in 35 patients with CHF with 35 age- and weight-matched healthy subjects. A second goal was to obtain cardiopulmonary variables measured at ventilatory threshold to distinguish patient changes from those of healthy subjects. Exercise testing was carried out using bicycle ergometry with ramplike protocol (work rate increments 12.5 W/min). Gas exchange and ventilation were measured breath by breath. Compared with healthy subjects, the VO2 in patients was lower at identical work rates (p rate, the variables for VO2, VCO2, ventilation, O2 pulse, ventilatory equivalents for O2 and CO2, and VD/VT (physiologic deadspace to tidal volume ratio), as well as lactate differed significantly at identical work rates. With the exception of VD/VT, all cardiopulmonary variables showed significant differences in their slopes during exercise. By means of a discriminant analysis, VCO2 and ventilation proved to be the most distinguishing variables at ventilatory threshold between patients with CHF and healthy subjects. These results indicate the clinical usefulness of cardiopulmonary exercise testing when assessing functional impairment due to CHF. For treatment evaluation, not only VO2 but also VCO2 and ventilation responses to exercise should be considered.

  3. Classification of caesarean section and normal vaginal deliveries using foetal heart rate signals and advanced machine learning algorithms.

    Science.gov (United States)

    Fergus, Paul; Hussain, Abir; Al-Jumeily, Dhiya; Huang, De-Shuang; Bouguila, Nizar

    2017-07-06

    Visual inspection of cardiotocography traces by obstetricians and midwives is the gold standard for monitoring the wellbeing of the foetus during antenatal care. However, inter- and intra-observer variability is high with only a 30% positive predictive value for the classification of pathological outcomes. This has a significant negative impact on the perinatal foetus and often results in cardio-pulmonary arrest, brain and vital organ damage, cerebral palsy, hearing, visual and cognitive defects and in severe cases, death. This paper shows that using machine learning and foetal heart rate signals provides direct information about the foetal state and helps to filter the subjective opinions of medical practitioners when used as a decision support tool. The primary aim is to provide a proof-of-concept that demonstrates how machine learning can be used to objectively determine when medical intervention, such as caesarean section, is required and help avoid preventable perinatal deaths. This is evidenced using an open dataset that comprises 506 controls (normal virginal deliveries) and 46 cases (caesarean due to pH ≤ 7.20-acidosis, n = 18; pH > 7.20 and pH machine-learning algorithms are trained, and validated, using binary classifier performance measures. The findings show that deep learning classification achieves sensitivity = 94%, specificity = 91%, Area under the curve = 99%, F-score = 100%, and mean square error = 1%. The results demonstrate that machine learning significantly improves the efficiency for the detection of caesarean section and normal vaginal deliveries using foetal heart rate signals compared with obstetrician and midwife predictions and systems reported in previous studies.

  4. Detection and prognostic impact of renal dysfunction in patients with chronic heart failure and normal serum creatinine.

    Science.gov (United States)

    Scrutinio, Domenico; Passantino, Andrea; Lagioia, Rocco; Santoro, Daniela; Cacciapaglia, Erasmo

    2011-03-03

    Accurate identification of renal dysfunction (RD) is crucial to risk stratification in chronic heart failure (CHF). Patients with CHF are at special risk of having RD despite normal serum creatinine (SCr), owing to a decreased Cr generation. At low levels of SCr, the equations estimating renal function are less accurate. This study was aimed to assess and compare the prognostic value of formulas estimating renal function in CHF patients with normal SCr. We studied 462 patients with systolic CHF and normal SCr. Creatinine clearance was estimated by the Cockcroft-Gault (eCrCl) and glomerular filtration rate by the 4-variable MDRD equation (eGFR); eCrCl normalized for body-surface area (eCrCl(BSA)) was calculated. The primary outcome was all-cause mortality at 2 years. Seventy five patients died. At multivariate Cox regression analysis, only eCrCl(BSA) was significantly associated with mortality (p = 0.006); eGFR (p = 0.24), eCrCl (p = 0.09) and BUN (p = 0.14) were not statistically significant predictors. The patients in the lowest eCrCl(BSA) quartile had an adjusted 2.1-fold (CI: 1.06-4.1) increased risk of mortality, compared with those in the referent quartile. Two-year survival was 70.4% in the lowest eCrCl(BSA) quartile and 89.7% in the referent quartile. Other independent predictors of mortality were ischemic etiology (RR: 2.16 [CI: 1.3-3.5], p = 0.0017), NYHA III/IV class (RR: 2.45 [CI: 1.51-3.97], p = 0.0003), LVEF high-risk subgroup and can more accurately be identified by the CG formula corrected for BSA than the MDRD. Copyright © 2009 Elsevier B.V. All rights reserved.

  5. Normal values for myocardial deformation within the right heart measured by feature-tracking cardiovascular magnetic resonance imaging.

    Science.gov (United States)

    Liu, Boyang; Dardeer, Ahmed M; Moody, William E; Edwards, Nicola C; Hudsmith, Lucy E; Steeds, Richard P

    2018-02-01

    Reproducible and repeatable assessment of right heart function is vital for monitoring congenital and acquired heart disease. There is increasing evidence for the additional value of myocardial deformation (strain and strain rate) in determining prognosis. This study aims to determine the reproducibility of deformation analyses in the right heart using cardiovascular magnetic resonance feature tracking (FT-CMR); and to establish normal ranges within an adult population. A cohort of 100 healthy subjects containing 10 males and 10 females from each decade of life between the ages of 20 and 70 without known congenital or acquired cardiovascular disease, hypertension, diabetes, dyslipidaemia or renal, hepatic, haematologic and systemic inflammatory disorders underwent FT-CMR assessment of right ventricular (RV) and right atrial (RA) myocardial strain and strain rate. RV longitudinal strain (Ell) was -21.9±3.24% (FW+S Ell) and -24.2±3.59% (FW-Ell). Peak systolic strain rate (S') was -1.45±0.39s -1 (FW+S) and -1.54±0.41s -1 (FW). Early diastolic strain rate (E') was 1.04±0.26s -1 (FW+S) and 1.04±0.33s -1 (FW). Late diastolic strain rate (A') was 0.94±0.33s -1 (FW+S) and 1.08±0.33s -1 (FW). RA peak strain was -21.1±3.76%. The intra- and inter-observer ICC for RV Ell (FW+S) was 0.92 and 0.80 respectively, while for RA peak strain was 0.92 and 0.89 respectively. Normal values of RV & RA deformation for healthy individuals using FT-CMR are provided with good RV Ell and RA peak strain reproducibility. Strain rate suffered from sub-optimal reproducibility and may not be satisfactory for clinical use. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Biological Rhythms in the Skin

    Directory of Open Access Journals (Sweden)

    Mary S. Matsui

    2016-05-01

    Full Text Available Circadian rhythms, ≈24 h oscillations in behavior and physiology, are reflected in all cells of the body and function to optimize cellular functions and meet environmental challenges associated with the solar day. This multi-oscillatory network is entrained by the master pacemaker located in the suprachiasmatic nucleus (SCN of the hypothalamus, which directs an organism’s rhythmic expression of physiological functions and behavior via a hierarchical system. This system has been highly conserved throughout evolution and uses transcriptional–translational autoregulatory loops. This master clock, following environmental cues, regulates an organism’s sleep pattern, body temperature, cardiac activity and blood pressure, hormone secretion, oxygen consumption and metabolic rate. Mammalian peripheral clocks and clock gene expression have recently been discovered and are present in all nucleated cells in our body. Like other essential organ of the body, the skin also has cycles that are informed by this master regulator. In addition, skin cells have peripheral clocks that can function autonomously. First described in 2000 for skin, this review summarizes some important aspects of a rapidly growing body of research in circadian and ultradian (an oscillation that repeats multiple times during a 24 h period cutaneous rhythms, including clock mechanisms, functional manifestations, and stimuli that entrain or disrupt normal cycling. Some specific relationships between disrupted clock signaling and consequences to skin health are discussed in more depth in the other invited articles in this IJMS issue on Sleep, Circadian Rhythm and Skin.

  7. Rhythm in language acquisition.

    Science.gov (United States)

    Langus, Alan; Mehler, Jacques; Nespor, Marina

    2017-10-01

    Spoken language is governed by rhythm. Linguistic rhythm is hierarchical and the rhythmic hierarchy partially mimics the prosodic as well as the morpho-syntactic hierarchy of spoken language. It can thus provide learners with cues about the structure of the language they are acquiring. We identify three universal levels of linguistic rhythm - the segmental level, the level of the metrical feet and the phonological phrase level - and discuss why primary lexical stress is not rhythmic. We survey experimental evidence on rhythm perception in young infants and native speakers of various languages to determine the properties of linguistic rhythm that are present at birth, those that mature during the first year of life and those that are shaped by the linguistic environment of language learners. We conclude with a discussion of the major gaps in current knowledge on linguistic rhythm and highlight areas of interest for future research that are most likely to yield significant insights into the nature, the perception, and the usefulness of linguistic rhythm. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Implementation and reimbursement of remote monitoring for cardiac implantable electronic devices in Europe: a survey from the health economics committee of the European Heart Rhythm Association.

    Science.gov (United States)

    Mairesse, Georges H; Braunschweig, Frieder; Klersy, Katherine; Cowie, Martin R; Leyva, Francisco

    2015-05-01

    Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) permits early detection of arrhythmias, device, and lead failure and may also be useful in risk-predicting patient-related outcomes. Financial benefits for patients and healthcare organizations have also been shown. We sought to assess the implementation and funding of RM of CIEDs, including conventional pacemakers (PMs), implantable cardioverter defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices in Europe. Electronic survey from 43 centres in 15 European countries. In the study sample, RM was available in 22% of PM patients, 74% of ICD patients, and 69% of CRT patients. The most significant perceived benefits were the early detection of atrial arrhythmias in pacemaker patients, lead failure in ICD patients, and worsening heart failure in CRT patients. Remote monitoring was reported to lead a reduction of in-office follow-ups for all devices. The most important reported barrier to the implementation of RM for all CIEDs was lack of reimbursement (80% of centres). Physicians regard RM of CIEDs as a clinically useful technology that affords significant benefits for patients and healthcare organizations. Remote monitoring, however, is perceived as increasing workload. Reimbursement for RM is generally perceived as a major barrier to implementation. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  9. Clinical Characteristics and Findings of 99mTc-MIBI Heart SPECT in Patients with Acute Myocardial Infarction with Normal Coronary Arteriography

    International Nuclear Information System (INIS)

    Park, Myung Jae; Choi, Tae Youl; Kim, Deong Yoon; Kang, Heung Sun; Choue, Chung Whee; Kim, Kwon Sam; Kim, Kwang Won; Kim, Myung Shick; Song, Jung Sang; Bae, Jong Hoa

    1993-01-01

    Among 64 patients with acute myocardial infarction who underwent coronary angiography, 7 patients (10.9%)showed normal coronary artery. Six patients were men and 1 patient was female. The mean age of patients were 31.1 ± 3.9 years. Among the risk factors of coronary heart disease, smoking was most probable factor in patients with acute myocardial infarction with normal coronary angiography. 99m Tc-MIBI heart SPECT performed 5 of 7 patients and showed that it could be used in diagnosis, localization, extent of infarct area in patients with acute myocardial infarction with normal coronary angiography. But follow up 99m Tc-MIBI heart SPECT study will be needed to define the ability of myocardial viability in this patients.

  10. Heart rate variability and QT dispersion study in brain death patients and comatose patients with normal brainstem function

    International Nuclear Information System (INIS)

    Vakilian, A.R.; Iranmanesh, F.; Nadimi, A.E.; Kahnali, J.A.

    2011-01-01

    To compare heart rate variability (HRV) and QT dispersion in comatose patients with normal brainstem function and with brain death. Fourteen brain death patients with clinical signs of imminent brain death and 15 comatose patients were examined by neurologist in intensive care unit. HRV, RR interval and QT dispersion on ECG were assessed for 24 hours in both groups. Independent t-test and chi-square test were used for statistical analysis to determine significance which was set at p < 0.05. According to Holter findings, mean of standard deviation of RR-interval in the comatose and brain death groups was 48.33 and 35 respectively (p = 0.045). Mean of covariance coefficient of RR-interval was 0.065 in the comatose group and 0.043 in the brain deaths (p = 0.006). QT dispersion was not significant difference in two groups. HRV and RR-interval analysis appeared as an early finding for the diagnosis of brainstem death in comparison to comatose patients with normal brainstem function. QT dispersion had not significant in this regard. (author)

  11. Assessment of myocardial washout of Tc-99m-sestamibi in patients with chronic heart failure. Comparison with normal control

    Energy Technology Data Exchange (ETDEWEB)

    Kumita, Shin-ichiro; Seino, Yoshihiko; Cho, Keiichi; Nakajo, Hidenobu; Toba, Masahiro; Fukushima, Yoshimitsu; Takano, Teruo; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan); Okamoto, Noriake [Bristol-Myers Squibb K.K., Tokyo (Japan)

    2002-06-01

    In contrast to {sup 201}TlCl, {sup 99m}Tc-sestamibi shows very slow myocardial clearance after its initial myocardial uptake. In the present study, myocardial washout of {sup 99m}Tc-sestamibi was calculated in patients with non-ischemic chronic heart failure (CHF) and compared with biventricular parameters obtained from first-pass and ECG-gated myocardial perfusion SPECT data. After administration of {sup 99m}Tc-sestamibi, 25 patients with CHF and 8 normal controls (NC) were examined by ECG-gated myocardial perfusion SPECT and planar data acquisition in the early and delayed (interval of 3 hours) phase. Left ventricular ejection fraction (LVEF, %), peak filling rate (PFR, sec{sup -1}), end-diastolic volume (LVEDV, ml) and end-systolic volume (LVESV, ml) were automatically calculated from the ECG-gated SPECT data. Myocardial washout rates over 3 hours were calculated from the early and delayed planar images. Myocardial washout rates in the CHF group (39.6{+-}5.2%) were significantly higher than those in the NC group (31.2{+-}5.5%, p<0.01). The myocardial washout rates for the 33 subjects showed significant correlations with LVEF (r=-0.61, p<0.001), PFR (r=-0.47, p<0.01), LVEDV (r=0.45, p<0.01) and LVESV (r=0.48, p<0.01). The myocardial washout rate of {sup 99m}Tc-sestamibi is considered to be a novel marker for the diagnosis of myocardial damage in patients with chronic heart failure. (author)

  12. Cloning, chromosomal localization, and functional expression of the alpha 1 subunit of the L-type voltage-dependent calcium channel from normal human heart

    NARCIS (Netherlands)

    Schultz, D; Mikala, G; Yatani, A; Engle, D B; Iles, D E; Segers, B; Sinke, R J; Weghuis, D O; Klöckner, U; Wakamori, M

    1993-01-01

    A unique structural variant of the cardiac L-type voltage-dependent calcium channel alpha 1 subunit cDNA was isolated from libraries derived from normal human heart mRNA. The deduced amino acid sequence shows significant homology to other calcium channel alpha 1 subunits. However, differences from

  13. Daily rhythm of cerebral blood flow velocity

    Directory of Open Access Journals (Sweden)

    Spielman Arthur J

    2005-03-01

    Full Text Available Abstract Background CBFV (cerebral blood flow velocity is lower in the morning than in the afternoon and evening. Two hypotheses have been proposed to explain the time of day changes in CBFV: 1 CBFV changes are due to sleep-associated processes or 2 time of day changes in CBFV are due to an endogenous circadian rhythm independent of sleep. The aim of this study was to examine CBFV over 30 hours of sustained wakefulness to determine whether CBFV exhibits fluctuations associated with time of day. Methods Eleven subjects underwent a modified constant routine protocol. CBFV from the middle cerebral artery was monitored by chronic recording of Transcranial Doppler (TCD ultrasonography. Other variables included core body temperature (CBT, end-tidal carbon dioxide (EtCO2, blood pressure, and heart rate. Salivary dim light melatonin onset (DLMO served as a measure of endogenous circadian phase position. Results A non-linear multiple regression, cosine fit analysis revealed that both the CBT and CBFV rhythm fit a 24 hour rhythm (R2 = 0.62 and R2 = 0.68, respectively. Circadian phase position of CBT occurred at 6:05 am while CBFV occurred at 12:02 pm, revealing a six hour, or 90 degree difference between these two rhythms (t = 4.9, df = 10, p Conclusion In conclusion, time of day variations in CBFV have an approximately 24 hour rhythm under constant conditions, suggesting regulation by a circadian oscillator. The 90 degree-phase angle difference between the CBT and CBFV rhythms may help explain previous findings of lower CBFV values in the morning. The phase difference occurs at a time period during which cognitive performance decrements have been observed and when both cardiovascular and cerebrovascular events occur more frequently. The mechanisms underlying this phase angle difference require further exploration.

  14. CARDIOTHORACIC RATIO AND VERTEBRAL HEART SCALE IN CLINICALLY NORMAL BLACK-RUMPED AGOUTIS (DASYPROCTA PRYMNOLOPHA, WAGLER 1831).

    Science.gov (United States)

    de Moura, Charlys Rhands Coelho; das Neves Diniz, Anaemilia; da Silva Moura, Laecio; das Chagas Araújo Sousa, Francisco; Baltazar, Pollyana Irene; Freire, Larisse Danielle; Guerra, Porfírio Candanedo; de Sousa, João Macedo; Giglio, Robson Fortes; Pessoa, Gerson Tavares; de Sá, Renan Paraguassu; Alves, Flávio Ribeiro

    2015-06-01

    Wild rodents, such as the lowland paca (Cuniculus paca), capybara (Hydrochoerus hydrochaeris), rock cavy (Kerodon rupestris), guinea pig (Cavia aperea), and black-rumped agouti (Dasyprocta prymnolopha) are intensely hunted throughout Amazonia and at the semiarid regions of northeastern Brazil. To contribute to the preservation of these species, more information about their anatomy, physiology and pathophysiology is needed. The aim of this study was to standardize the vertebral heart scale (VHS) and cardiothoracic ratio (CTR) in clinically normal black-rumped agouti, as well as to compare the results of these two methods, which are commonly used to evaluate the cardiac silhouette in domestic animals. Twelve healthy black-rumped agoutis, divided into two groups (six males and six females), obtained from the Nucleus for Wild Animal Studies and Conservation at the Federal University of Piauí, were radiographed in right and left lateral and dorsoventral projections. The values of the VHS were 8.00±0.31v (the number of thoracic vertebral length spanned by each dimension, starting at T4) for males and 8.11±0.41v for females, and there was no statistical difference between the decubitus (right and left) or between males and females (P>0.05). The CTR mean values obtained were 0.51±0.03 for males, and 0.52±0.02 for females, and there was no statistical difference between the genders (P>0.05). However, there was positive correlation between VHS and CTR (r=0.77 right decubitus and r=0.82 left decubitus). The thoracic and heart diameter had mean values of 6.72±0.61 and 3.48±0.30 cm (males), and for the females, it was 6.61±0.51 and 3.5±0.30 cm, respectively, and there was statistical difference between the genders. The results demonstrated high correlation between the VHS and CTR producing similar results, indicating similar clinical precision for assessing the size of the cardiac silhouette in the black-rumped agoutis.

  15. ACC/AATS/AHA/ASE/ASNC/HRS/SCAI/SCCT/SCMR/STS 2017 Appropriate Use Criteria for Multimodality Imaging in Valvular Heart Disease: A Report of the American College of Cardiology Appropriate Use Criteria Task Force, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

    Science.gov (United States)

    Doherty, John U; Kort, Smadar; Mehran, Roxana; Schoenhagen, Paul; Soman, Prem; Dehmer, Greg J; Doherty, John U; Schoenhagen, Paul; Amin, Zahid; Bashore, Thomas M; Boyle, Andrew; Calnon, Dennis A; Carabello, Blase; Cerqueira, Manuel D; Conte, John; Desai, Milind; Edmundowicz, Daniel; Ferrari, Victor A; Ghoshhajra, Brian; Mehrotra, Praveen; Nazarian, Saman; Reece, T Brett; Tamarappoo, Balaji; Tzou, Wendy S; Wong, John B; Doherty, John U; Dehmer, Gregory J; Bailey, Steven R; Bhave, Nicole M; Brown, Alan S; Daugherty, Stacie L; Dean, Larry S; Desai, Milind Y; Duvernoy, Claire S; Gillam, Linda D; Hendel, Robert C; Kramer, Christopher M; Lindsay, Bruce D; Manning, Warren J; Mehrotra, Praveen; Patel, Manesh R; Sachdeva, Ritu; Wann, L Samuel; Winchester, David E; Wolk, Michael J; Allen, Joseph M

    2018-04-01

    This document is 1 of 2 companion appropriate use criteria (AUC) documents developed by the American College of Cardiology, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons. This document addresses the evaluation and use of multimodality imaging in the diagnosis and management of valvular heart disease, whereas the second, companion document addresses this topic with regard to structural heart disease. Although there is clinical overlap, the documents addressing valvular and structural heart disease are published separately, albeit with a common structure. The goal of the companion AUC documents is to provide a comprehensive resource for multimodality imaging in the context of valvular and structural heart disease, encompassing multiple imaging modalities. Using standardized methodology, the clinical scenarios (indications) were developed by a diverse writing group to represent patient presentations encountered in everyday practice and included common applications and anticipated uses. Where appropriate, the scenarios were developed on the basis of the most current American College of Cardiology/American Heart Association guidelines. A separate, independent rating panel scored the 92 clinical scenarios in this document on a scale of 1 to 9. Scores of 7 to 9 indicate that a modality is considered appropriate for the clinical scenario presented. Midrange scores of 4 to 6 indicate that a modality may be appropriate for the clinical scenario, and scores of 1 to 3 indicate that a modality is considered rarely appropriate for the clinical scenario. The primary objective of the AUC is to provide a framework for the assessment of these scenarios by practices that will

  16. ACC/AATS/AHA/ASE/ASNC/HRS/SCAI/SCCT/SCMR/STS 2017 Appropriate Use Criteria for Multimodality Imaging in Valvular Heart Disease : A Report of the American College of Cardiology Appropriate Use Criteria Task Force, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

    Science.gov (United States)

    Doherty, John U; Kort, Smadar; Mehran, Roxana; Schoenhagen, Paul; Soman, Prem

    2017-12-01

    This document is 1 of 2 companion appropriate use criteria (AUC) documents developed by the American College of Cardiology, American Association for Thoracic Surgery, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons. This document addresses the evaluation and use of multimodality imaging in the diagnosis and management of valvular heart disease, whereas the second, companion document addresses this topic with regard to structural heart disease. Although there is clinical overlap, the documents addressing valvular and structural heart disease are published separately, albeit with a common structure. The goal of the companion AUC documents is to provide a comprehensive resource for multimodality imaging in the context of valvular and structural heart disease, encompassing multiple imaging modalities.Using standardized methodology, the clinical scenarios (indications) were developed by a diverse writing group to represent patient presentations encountered in everyday practice and included common applications and anticipated uses. Where appropriate, the scenarios were developed on the basis of the most current American College of Cardiology/American Heart Association guidelines.A separate, independent rating panel scored the 92 clinical scenarios in this document on a scale of 1 to 9. Scores of 7 to 9 indicate that a modality is considered appropriate for the clinical scenario presented. Midrange scores of 4 to 6 indicate that a modality may be appropriate for the clinical scenario, and scores of 1 to 3 indicate that a modality is considered rarely appropriate for the clinical scenario.The primary objective of the AUC is to provide a framework for the assessment of these scenarios by practices that will

  17. Correcting human heart 31P NMR spectra for partial saturation. Evidence that saturation factors for PCr/ATP are homogeneous in normal and disease states

    Science.gov (United States)

    Bottomley, Paul A.; Hardy, Christopher J.; Weiss, Robert G.

    Heart PCr/ATP ratios measured from spatially localized 31P NMR spectra can be corrected for partial saturation effects using saturation factors derived from unlocalized chest surface-coil spectra acquired at the heart rate and approximate Ernst angle for phosphor creatine (PCr) and again under fully relaxed conditions during each 31P exam. To validate this approach in studies of normal and disease states where the possibility of heterogeneity in metabolite T1 values between both chest muscle and heart and normal and disease states exists, the properties of saturation factors for metabolite ratios were investigated theoretically under conditions applicable in typical cardiac spectroscopy exams and empirically using data from 82 cardiac 31P exams in six study groups comprising normal controls ( n = 19) and patients with dilated ( n = 20) and hypertrophic ( n = 5) cardiomyopathy, coronary artery disease ( n = 16), heart transplants ( n = 19), and valvular heart disease ( n = 3). When TR ≪ T1,(PCr), with T1(PCr) ⩾ T1(ATP), the saturation factor for PCr/ATP lies in the range 1.5 ± 0.5, regardless of the T1 values. The precise value depends on the ratio of metabolite T1 values rather than their absolute values and is insensitive to modest changes in TR. Published data suggest that the metabolite T1 ratio is the same in heart and muscle. Our empirical data reveal that the saturation factors do not vary significantly with disease state, nor with the relative fractions of muscle and heart contributing to the chest surface-coil spectra. Also, the corrected myocardial PCr/ATP ratios in each normal or disease state bear no correlation with the corresponding saturation factors nor the fraction of muscle in the unlocalized chest spectra. However, application of the saturation correction (mean value, 1.36 ± 0.03 SE) significantly reduced scatter in myocardial PCr/ATP data by 14 ± 11% (SD) ( p ⩽ 0.05). The findings suggest that the relative T1 values of PCr and ATP are

  18. Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ning; ZHANG Hui-Min; LIU Zhi-Qiang; DING Xue-Li; YANG Ming-Hao; GU Hua-Guang; REN Wei

    2009-01-01

    Dissolved cardiac myocytes can couple together and generate synchronous beatings in culture. We observed a synchronized early after-depolarization(EAD)-like rhythm in cultured cardiac myocytes and reproduced the experimental observation in a network mathematical model whose dynamics are close to a Hopf bifurcation. The mechanism for this EAD-like rhythm is attributed to noised-induced stochastic alternatings between the focus and the limit cycle. These results provide novel understandings for pathological heart rhythms like the early immature beatings.

  19. The consequences of long-term glycogen synthase kinase-3 inhibition on normal and insulin resistant rat hearts.

    Science.gov (United States)

    Flepisi, T B; Lochner, Amanda; Huisamen, Barbara

    2013-10-01

    Glycogen synthase kinase-3 (GSK-3) is a serine-threonine protein kinase, discovered as a regulator of glycogen synthase. GSK-3 may regulate the expression of SERCA-2a potentially affecting myocardial contractility. It is known to phosphorylate and inhibit IRS-1, thus disrupting insulin signalling. This study aimed to determine whether myocardial GSK-3 protein and its substrate proteins are dysregulated in obesity and insulin resistance, and whether chronic GSK-3 inhibition can prevent or reverse this. Weight matched male Wistar rats were rendered obese by hyperphagia using a special diet (DIO) for 16 weeks and compared to chow fed controls. Half of each group was treated with the GSK-3 inhibitor CHIR118637 (30 mg/kg/day) from week 12 to16 of the diet period. Biometric and biochemical parameters were measured and protein expression determined by Western blotting and specific antibodies. Ca(2+)ATPase activity was determined spectrophotometrically. Cardiomyocytes were prepared by collagenase perfusion and insulin stimulated 2-deoxy-glucose uptake determined. DIO rats were significantly heavier than controls, associated with increased intra-peritoneal fat and insulin resistance. GSK-3 inhibition did not affect weight but improved insulin resistance, also on cellular level. It had no effect on GSK-3 expression but elevated its phospho/total ratio and elevated IRS-2 expression. Obesity lowered SERCA-2a expression and activity while GSK-3 inhibition alleviated this. The phospho/total ratio of phospholamban underscored inhibition of SERCA-2a in obesity. In addition, signs of myocardial hypertrophy were observed in treated control rats. GSK-3 inhibition could not reverse all the detrimental effects of obesity but may be harmful in normal rat hearts. It regulates IRS-2, SERCA-2a and phospholamban expression but not IRS-1.

  20. 99mTc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    International Nuclear Information System (INIS)

    Okada, David R.; Liu, Zhonglin; Johnson, Gerald; Okada, Robert D.; Beju, Delia; Khaw, Ban An

    2010-01-01

    99m Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine 99m Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). 99m Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. 99m Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 ± 0.09) (cpm, SEM) than in control (1.74 ± 0.07), stunned (1.68 ± 0.11), and hibernating (1.59 ± 0.11) (p 99m Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 ± 0.63) than in control (1.98 ± 0.15), stunned (1.79 ± 0.08), and hibernating (2.33 ± 0.15) (p 99m Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. 99m Tc-glucarate uptake was strongly correlated with myocardial necrosis as determined by three independent assessments of viability. There were minimal and similar 99m Tc-glucarate uptakes in control, stunned, and hibernating myocardium. (orig.)

  1. Progressive epicardial coronary blood flow reduction fails to produce ST-segment depression at normal heart rates.

    Science.gov (United States)

    de Chantal, Marilyn; Diodati, Jean G; Nasmith, James B; Amyot, Robert; LeBlanc, A Robert; Schampaert, Erick; Pharand, Chantal

    2006-12-01

    ST-segment depression is commonly seen in patients with acute coronary syndromes. Most authors have attributed it to transient reductions in coronary blood flow due to nonocclusive thrombus formation on a disrupted atherosclerotic plaque and dynamic focal vasospasm at the site of coronary artery stenosis. However, ST-segment depression was never reproduced in classic animal models of coronary stenosis without the presence of tachycardia. We hypothesized that ST-segment depression occurring during acute coronary syndromes is not entirely explained by changes in epicardial coronary artery resistance and thus evaluated the effect of a slow, progressive epicardial coronary artery occlusion on the ECG and regional myocardial blood flow in anesthetized pigs. Slow, progressive occlusion over 72 min (SD 27) of the left anterior descending coronary artery in 20 anesthetized pigs led to a 90% decrease in coronary blood flow and the development of ST-segment elevation associated with homogeneous and transmural myocardial blood flow reductions, confirmed by microspheres and myocardial contrast echocardiography. ST-segment depression was not observed in any ECG lead before the development of ST-segment elevation. At normal heart rates, progressive epicardial stenosis of a coronary artery results in myocardial ischemia associated with homogeneous, transmural reduction in regional myocardial blood flow and ST-segment elevation, without preceding ST-segment depression. Thus, in coronary syndromes with ST-segment depression and predominant subendocardial ischemia, factors other than mere increases in epicardial coronary resistance must be invoked to explain the heterogeneous parietal distribution of flow and associated ECG changes.

  2. Role of diabetes in heart rhythm disorders

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    The incidence of diabetes mellitus (DM) is increasingrapidly. DM is the leading cause of cardiovascular diseases,which can lead to varied cardiovascular complications byaggravated atherosclerosis in large arteries and coronaryatherosclerosis, thereby grows the risk for macro andmicroangiopathy such as myocardial infarction, stroke,limb loss and retinopathy. Moreover diabetes is one of thestrongest and independent risk factor for cardiovascularmorbidity and mortality, which associated frequentlyrhythm disorders such as atrial fibrillation (AF) andventricular arrhythmias (VA). The present article providesa concise overview of the association between DM andrhythm disorders such as AF and VA with underlyingpathophysiological mechanisms.

  3. Reflex control of heart rate in normal subjects in relation to age: a data base for cardiac vagal neuropathy

    NARCIS (Netherlands)

    Wieling, W.; van Brederode, J. F.; de Rijk, L. G.; Borst, C.; Dunning, A. J.

    1982-01-01

    We examined the heart rate changes induced by forced breathing and by standing up in 133 healthy subjects in the age range 10-65 years in order to establish a data base for studies on parasympathetic heart rate control in autonomic neuropathy. Test results declined with age. Log-transformation was

  4. RHYTHM STRUCTURE IN NEWS READING

    Directory of Open Access Journals (Sweden)

    Lluís Mas Manchón

    2013-06-01

    Full Text Available Rhythm is central to news reading in radio and television programs. This paper proposes a three level structure for rhythm in news discourse. It gives a comprehensive definition of rhythm and types of rhythm. Firstly, the Base Rhythm Structure consists of semantic and pragmatic rhythmic accents, coincident with very specific words. Secondly, these accents are grouped together according to type, frequency and order, thereby configuring three types of “rhythmic units” (the Internal Rhythm Structure: starting, main and end units. A last structure level presents four discursive factors that are very important in integrating the overall time structure of news announcing (the Melodic Rhythm Structure. This integral structure for news announcing rhythm should be further tested in acoustic-experimental studies under the criterion of information transmission efficacy.

  5. Hypothyroidism and the Heart

    Science.gov (United States)

    Udovcic, Maja; Pena, Raul Herrera; Patham, Bhargavi; Tabatabai, Laila; Kansara, Abhishek

    2017-01-01

    Hypothyroidism is a commonly encountered clinical condition with variable prevalence. It has profound effects on cardiac function that can impact cardiac contractility, vascular resistance, blood pressure, and heart rhythm. With this review, we aim to describe the effects of hypothyroidism and subclinical hypothyroidism on the heart. Additionally, we attempt to briefly describe how hypothyroid treatment affects cardiovascular parameters. PMID:28740582

  6. Hypothyroidism and the Heart.

    Science.gov (United States)

    Udovcic, Maja; Pena, Raul Herrera; Patham, Bhargavi; Tabatabai, Laila; Kansara, Abhishek

    2017-01-01

    Hypothyroidism is a commonly encountered clinical condition with variable prevalence. It has profound effects on cardiac function that can impact cardiac contractility, vascular resistance, blood pressure, and heart rhythm. With this review, we aim to describe the effects of hypothyroidism and subclinical hypothyroidism on the heart. Additionally, we attempt to briefly describe how hypothyroid treatment affects cardiovascular parameters.

  7. Light Rhythms in Architecture

    DEFF Research Database (Denmark)

    Bülow, Katja

    2013-01-01

    formation and rhythm. When integrated into an architectural concept, electrical lighting non-intended for poetic composition has the ability to contribute to place, time, and function-telling aspects of places in urban contexts. Urban environments are information wise challenging to pre-historic human...

  8. Biological Clocks & Circadian Rhythms

    Science.gov (United States)

    Robertson, Laura; Jones, M. Gail

    2009-01-01

    The study of biological clocks and circadian rhythms is an excellent way to address the inquiry strand in the National Science Education Standards (NSES) (NRC 1996). Students can study these everyday phenomena by designing experiments, gathering and analyzing data, and generating new experiments. As students explore biological clocks and circadian…

  9. The magnitude and course of exercise-induced stroke volume changes determine the exercise tolerance in heart transplant recipients with heart failure and normal ejection fraction

    Czech Academy of Sciences Publication Activity Database

    Meluzín, J.; Hude, P.; Leinveber, P.; Jurák, Pavel; Soukup, L.; Viščor, Ivo; Špinarová, L.; Štěpánová, R.; Podroužková, H.; Vondra, Vlastimil; Langer, P.; Němec, P.

    2014-01-01

    Roč. 20, č. 1 (2014), s. 674-687 ISSN 1205-6626 R&D Projects: GA MŠk(CZ) LO1212 Keywords : heart failure * stroke volume index * exercise tolerance * bioimpedance Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 0.758, year: 2013

  10. Pacing as a Treatment for Reflex-Mediated (Vasovagal, Situational, or Carotid Sinus Hypersensitivity) Syncope: A Systematic Review for the 2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society.

    Science.gov (United States)

    Varosy, Paul D; Chen, Lin Y; Miller, Amy L; Noseworthy, Peter A; Slotwiner, David J; Thiruganasambandamoorthy, Venkatesh

    2017-08-01

    , Inc., and Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  11. Clinical skills: cardiac rhythm recognition and monitoring.

    Science.gov (United States)

    Sharman, Joanna

    With technological advances, changes in provision of healthcare services and increasing pressure on critical care services, ward patients' severity of illness is ever increasing. As such, nurses need to develop their skills and knowledge to care for their client group. Competency in cardiac rhythm monitoring is beneficial to identify changes in cardiac status, assess response to treatment, diagnosis and post-surgical monitoring. This paper describes the basic anatomy and physiology of the heart and its conduction system, and explains a simple and easy to remember process of analysing cardiac rhythms (Resuscitation Council UK, 2000) that can be used in first-line assessment to assist healthcare practitioners in providing care to their patients.

  12. Low Left Atrial Compliance Contributes to the Clinical Recurrence of Atrial Fibrillation after Catheter Ablation in Patients with Structurally and Functionally Normal Heart.

    Science.gov (United States)

    Park, Junbeom; Yang, Pil-sung; Kim, Tae-Hoon; Uhm, Jae-Sun; Kim, Joung-Youn; Joung, Boyoung; Lee, Moon-Hyoung; Hwang, Chun; Pak, Hui-Nam

    2015-01-01

    Stiff left atrial (LA) syndrome was initially reported in post-cardiac surgery patients and known to be associated with low LA compliance. We investigated the physiological and clinical implications of LA compliance by estimating LA pulse pressure (LApp) among patients with atrial fibrillation (AF) and structurally and functionally normal heart. Among 1038 consecutive patients with LA pressure measurements before AF ablation, we included 334 patients with structurally and functionally normal heart (81.7% male, 54.1±10.6 years, 77.0% paroxysmal AF) after excluding those with hypertension, diabetes, and previous ablation or cardiac surgery. We measured LApp (peak-nadir LA pressure) at the beginning of the ablation procedure and compared the values with clinical parameters and the AF recurrence rate. AF patients with normal heart were younger and more frequently male and had paroxysmal AF, a lower body mass index, and a lower LApp compared to others (all p<0.05). Based on the median value, the low LA compliance group (LApp≥13 mmHg) had a smaller LA volume index and lower LA voltage (all p<0.05) compared to the high LA compliance group. During a mean follow-up of 16.7±11.8 months, low LA compliance was independently associated with two fold-higher risk of clinical AF recurrence (HR:2.202; 95%CI:1.077-4.503; p = 0.031). Low LA compliance, as determined by an elevated LApp, was associated with a smaller LA volume index and lower LA voltage and independently associated with higher clinical recurrence after catheter ablation in AF patients with structurally and functionally normal heart.

  13. {sup 99m}Tc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    Energy Technology Data Exchange (ETDEWEB)

    Okada, David R. [University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Liu, Zhonglin [University of Arizona School of Medicine, Tucson, AZ (United States); Johnson, Gerald; Okada, Robert D. [University of Oklahoma Health Sciences Center, Oklahoma, OK (United States); University of Tulsa, Tulsa, OK (United States); Beju, Delia [Oklahoma State University School of Medicine, Tulsa, OK (United States); Khaw, Ban An [Northeastern University, Boston, MA (United States)

    2010-10-15

    {sup 99m}Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine {sup 99m}Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). {sup 99m}Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. {sup 99m}Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 {+-} 0.09) (cpm, SEM) than in control (1.74 {+-} 0.07), stunned (1.68 {+-} 0.11), and hibernating (1.59 {+-} 0.11) (p < 0.05). Tracer retention curves for ischemic-reperfused were elevated at all time points as compared with the other groups. {sup 99m}Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 {+-} 0.63) than in control (1.98 {+-} 0.15), stunned (1.79 {+-} 0.08), and hibernating (2.33 {+-} 0.15) (p < 0.05). The 60-min well-counted tracer activity ratio of ischemic-reperfused to control was 9:1 and corroborated the NaI detector results. Creatine kinase, triphenyltetrazolium chloride, and electron microscopy all demonstrated significantly greater injury in ischemic-reperfused compared to the other groups. An excellent correlation was observed between viability markers and tracer activity (r = 0.99 triphenyltetrazolium chloride; r = 0.90 creatine kinase). {sup 99m}Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. {sup 99m}Tc-glucarate uptake was strongly correlated with myocardial necrosis as

  14. Non-invasive estimation of myocardial efficiency using positron emission tomography and carbon-11 acetate - comparison between the normal and failing human heart

    International Nuclear Information System (INIS)

    Bengel, F.M.; Nekolla, S.; Schwaiger, M.; Ungerer, M.

    2000-01-01

    We studied ten patients with idiopathic dilated cardiomyopathy (DCM) and 11 healthy normals by dynamic PET with 11 C-acetate and either tomographic radionuclide ventriculography or cine magnetic resonance imaging. A ''stroke work index'' (SWI) was calculated by: SWI = systolic blood pressure x stroke volume/body surface area. To estimate myocardial efficiency, a ''work-metabolic index'' (WMI) was then obtained as follows: WMI = SWI x heart rate/k(mono), where k(mono) is the washout constant for 11 C-acetate derived from mono-exponential fitting. In DCM patients, left ventricular ejection fraction was 19%±10% and end-diastolic volume was 92±28 ml/m 2 (vs 64%±7% and 55±8 ml/m 2 in normals, P 2 ; P 6 mmHg x ml/m 2 ; P<0.001) were lower in DCM patients, too. Overall, the WMI correlated positively with ejection parameters (r=0.73, P<0.001 for ejection fraction; r=0.93, P<0.001 for stroke volume), and inversely with systemic vascular resistance (r=-0.77; P<0.001). There was a weak positive correlation between WMI and end-diastolic volume in normals (r=0.45; P=0.17), while in DCM patients, a non-significant negative correlation coefficient (r=-0.21; P=0.57) was obtained. In conclusion non-invasive estimates of oxygen consumption and efficiency in the failing heart were reduced compared with those in normals. Estimates of efficiency increased with increasing contractile performance, and decreased with increasing ventricular afterload. In contrast to normals, the failing heart was not able to respond with an increase in efficiency to increasing ventricular volume.(orig./MG) (orig.)

  15. Circadian rhythms in the hypothalamo-pituitary-adrenal (HPA) axis

    NARCIS (Netherlands)

    Kalsbeek, A.; van der Spek, R.; Lei, J.; Endert, E.; Buijs, R. M.; Fliers, E.

    2012-01-01

    The pronounced daily variation in the release of adrenal hormones has been at the heart of the deciphering and understanding of the circadian timing system. Indeed, the first demonstration of an endocrine day/night rhythm was provided by Pincus (1943), by showing a daily pattern of 17-keto-steroid

  16. Maternal exercise, season and sex modify the human fetal circadian rhythm.

    Science.gov (United States)

    Sletten, Julie; Cornelissen, Germaine; Assmus, Jørg; Kiserud, Torvid; Albrechtsen, Susanne; Kessler, Jörg

    2018-05-13

    The knowledge on circadian rhythmicity is rapidly expanding. We aimed to define the longitudinal development of the circadian heart rate rhythm in the human fetus in an unrestricted, out-of-hospital setting, and to examine the effects of maternal physical activity, season and fetal sex. We recruited 48 women with low-risk singleton pregnancies. Using a portable monitor for continuous fetal electrocardiography, fetal heart rate recordings were obtained around gestational weeks 24, 28, 32 and 36. Circadian rhythmicity in fetal heart rate and fetal heart rate variation was detected by cosinor analysis; developmental trends were calculated by population-mean cosinor and multilevel analysis. For the fetal heart rate and fetal heart rate variation, a significant circadian rhythm was present in 122/123 (99.2%) and 116/121 (95.9%) of the individual recordings, respectively. The rhythms were best described by combining cosine waves with periods of 24 and 8 hours. With increasing gestational age, the magnitude of the fetal heart rate rhythm increased, and the peak of the fetal heart rate variation rhythm shifted from a mean of 14:25 (24 weeks) to 20:52 (36 weeks). With advancing gestation, the rhythm-adjusted mean value of the fetal heart rate decreased linearly in females (prhythm diversity was found in male fetuses, during higher maternal physical activity and during the summer season. The dynamic development of the fetal circadian heart rate rhythm during the second half of pregnancy is modified by fetal sex, maternal physical activity and season. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Glucagon-like peptide-1 reduces contractile function and fails to boost glucose utilization in normal hearts in the presence of fatty acids.

    Science.gov (United States)

    Nguyen, T Dung; Shingu, Yasushige; Amorim, Paulo A; Schwarzer, Michael; Doenst, Torsten

    2013-10-09

    GLP-1 and exendin-4, which are used as insulin sensitizers or weight reducing drugs, were shown to improve glucose uptake in the heart. However, the direct effects of GLP-1 or exendin-4 on normal hearts in the presence of fatty acids, the main cardiac substrates, have never been investigated. We therefore assessed the effects of GLP-1 or exendin-4 on myocardial glucose uptake (GU), glucose oxidation (GO) and cardiac performance (CP) under conditions of fatty acid utilization. Rat hearts were perfused with only glucose (5 mM) or glucose (5 mM) plus oleate (0.4 mM) as substrates for 60 min. After 30 min, GLP-1 or exendin-4 (0.5 nM or 5 nM) was added. In the absence of oleate, GLP-1 increased both GU and GO. Exendin-4 increased GO but showed no effect on GU. Neither GLP-1 nor exendin-4 affected CP. However, when oleate was present, GLP-1 failed to stimulate glucose utilization and exendin-4 even decreased GU. Furthermore, now GLP-1 reduced CP. In contrast to prior reports, this negative inotropic effect could not be blocked by the protein kinase A inhibitor H-89. We then measured myocardial GO and CP in rats receiving a 4-week GLP-1 infusion. Interestingly, this chronic treatment resulted in a significant reduction in both GO and CP. Under the influence of oleate, GLP-1 reduces contractile function and fails to stimulate glucose utilization in normal hearts. Exendin-4 may acutely reduce cardiac glucose uptake but not contractility. We suggest advanced investigation of heart function and metabolism in patients treating with these peptides. © 2013.

  18. Circadian Rhythms in Cyanobacteria

    Science.gov (United States)

    Golden, Susan S.

    2015-01-01

    SUMMARY Life on earth is subject to daily and predictable fluctuations in light intensity, temperature, and humidity created by rotation of the earth. Circadian rhythms, generated by a circadian clock, control temporal programs of cellular physiology to facilitate adaptation to daily environmental changes. Circadian rhythms are nearly ubiquitous and are found in both prokaryotic and eukaryotic organisms. Here we introduce the molecular mechanism of the circadian clock in the model cyanobacterium Synechococcus elongatus PCC 7942. We review the current understanding of the cyanobacterial clock, emphasizing recent work that has generated a more comprehensive understanding of how the circadian oscillator becomes synchronized with the external environment and how information from the oscillator is transmitted to generate rhythms of biological activity. These results have changed how we think about the clock, shifting away from a linear model to one in which the clock is viewed as an interactive network of multifunctional components that are integrated into the context of the cell in order to pace and reset the oscillator. We conclude with a discussion of how this basic timekeeping mechanism differs in other cyanobacterial species and how information gleaned from work in cyanobacteria can be translated to understanding rhythmic phenomena in other prokaryotic systems. PMID:26335718

  19. Effects of tritium-labeled pyrimidine nucleosides on epithelial cell proliferation in the mouse. I. Cytodynamic perturbations in normal circadian rhythms after a single injection of 3H-thymidine

    International Nuclear Information System (INIS)

    Olsson, L.

    1976-01-01

    In a combined stathmokinetic, autoradiographic, and microspectrophotometric study on the cytodynamics in mouse epidermis, cirdardian rhythms were observed in the number of cells within the various phases (except G 2 ) of the mitotic cell cycle, and in mitotic rate. S-Phase influx and efflux were computed and were found to vary during a 24-hr period. No diurnal rhythm was observed in mitotic rate in the epithelium of small intestine. 3 H-Thymidine (1 μCi/g; sp act 5 Ci/mmol) induced mitotic delay in labeled cells 2 to 8 hr after administration. A supranormal mitotic activity in unlabeled cells was observed 12 to 24 hr after injection of 3 H-TdR. ''Cold'' thymidine had no effects on epidermal cell proliferation. S-Phase duration and average cell cycle time were estimated by traditional cell kinetic methods. The results suggest a 3 H-TdR-induced synchrony in cells entering the S phase 0 to 15 hr after injection of the precursor. A mitotic delay was seen in small intestinal epithelium 2 to 6 hr after injection of the precursor

  20. Discrepancy between circadian rhythms of inulin and creatinine clearance

    NARCIS (Netherlands)

    van Acker, B. A.; Koomen, G. C.; Koopman, M. G.; Krediet, R. T.; Arisz, L.

    1992-01-01

    To elucidate the disparity between circadian rhythmicity of inulin and creatinine clearance, we simultaneously measured inulin and creatinine clearances every 3 hours during 1 day in 14 normal subjects and in 8 patients with nephrotic syndrome. All patients and normal subjects had a circadian rhythm

  1. Other Rhythm Disorders

    Science.gov (United States)

    ... and Live Our Interactive Cardiovascular Library has detailed animations and illustrations to help you learn about conditions, treatments and procedures related to heart disease and stroke. Popular Articles 1 Understanding Blood Pressure Readings 2 Sodium and Salt 3 Heart Attack Symptoms ...

  2. Reconstruction and Visualization of Fiber and Laminar Structure in the Normal Human Heart from Ex Vivo DTMRI Data

    International Nuclear Information System (INIS)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-01-01

    Background--The human heart is composed of a helical network of muscle fibers. These fibers are organized to form sheets that are separated by cleavage surfaces. This complex structure of fibers and sheets is responsible for the orthotropic mechanical properties of cardiac muscle. The understanding of the configuration of the 3D fiber and sheet structure is important for modeling the mechanical and electrical properties of the heart and changes in this configuration maybe of significant importance to understand the remodeling after myocardial infarction. Methods--Anisotropic least square filtering followed by fiber and sheet tracking techniques were applied to Diffusion Tensor Magnetic Resonance Imaging (DTMRI) data of the excised human heart. The fiber configuration was visualized by using thin tubes to increase 3-dimensional visual perception of the complex structure. The sheet structures were reconstructed from the DTMRI data, obtaining surfaces that span the wall from the endo- to the epicardium. All visualizations were performed using the high-quality ray-tracing software POV-Ray. Results--The fibers are shown to lie in sheets that have concave or convex transmural structure which correspond to histological studies published in the literature. The fiber angles varied depending on the position between the epi- and endocardium. The sheets had a complex structure that depended on the location within the myocardium. In the apex region the sheets had more curvature. Conclusions--A high-quality visualization algorithm applied to demonstrated high quality DTMRI data is able to elicit the comprehension of the complex 3 dimensional structure of the fibers and sheets in the heart

  3. Light Rhythms in Architecture

    DEFF Research Database (Denmark)

    Bülow, Katja

    2013-01-01

    On one hand, urban lighting expresses itself in a complex visual environment made by the interplay by between many separate lighting schemes, as street lighting, shop lighting, luminous commercials etc. On the other, a noticeable order of patterns occurs, when lighting is observed as luminous...... formation and rhythm. When integrated into an architectural concept, electrical lighting non-intended for poetic composition has the ability to contribute to place, time, and function-telling aspects of places in urban contexts. Urban environments are information wise challenging to pre-historic human...... instincts, but they can be met by careful selection and adjustment of existing light situations....

  4. Orchestrating intensities and rhythms

    DEFF Research Database (Denmark)

    Staunæs, Dorthe; Juelskjær, Malou

    2016-01-01

    environmentality and learning-centered governance standards has dramatic and performative effects for the production of (educational) subjectivities. This implies a shift from governing identities, categories and structures towards orchestrating affective intensities and rhythms. Finally, the article discusses...... and the making of subjects have held sway for many years; and it is also well known that schools have been some of the most regular purchasers of psychological methods, tests and classifications. Following but also elaborating upon governmentality studies, it is suggested that a current shift towards...

  5. Reconstruction and Visualization of Fiber and Laminar Structure inthe Normal Human Heart from Ex Vivo DTMRI Data

    Energy Technology Data Exchange (ETDEWEB)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-12-18

    Background - The human heart is composed of a helicalnetwork of muscle fibers. These fibers are organized to form sheets thatare separated by cleavage surfaces. This complex structure of fibers andsheets is responsible for the orthotropic mechanical properties ofcardiac muscle. The understanding of the configuration of the 3D fiberand sheet structure is important for modeling the mechanical andelectrical properties of the heart and changes in this configuration maybe of significant importance to understand the remodeling aftermyocardial infarction.Methods - Anisotropic least square filteringfollowed by fiber and sheet tracking techniques were applied to DiffusionTensor Magnetic Resonance Imaging (DTMRI) data of the excised humanheart. The fiber configuration was visualized by using thin tubes toincrease 3-dimensional visual perception of the complex structure. Thesheet structures were reconstructed from the DTMRI data, obtainingsurfaces that span the wall from the endo- to the epicardium. Allvisualizations were performed using the high-quality ray-tracing softwarePOV-Ray. Results - The fibers are shown to lie in sheets that haveconcave or convex transmural structure which correspond to histologicalstudies published in the literature. The fiber angles varied depending onthe position between the epi- and endocardium. The sheets had a complexstructure that depended on the location within the myocardium. In theapex region the sheets had more curvature. Conclusions - A high-qualityvisualization algorithm applied to demonstrated high quality DTMRI datais able to elicit the comprehension of the complex 3 dimensionalstructure of the fibers and sheets in the heart.

  6. Serum bilirubin and antioxidant levels in first degree relatives of patients with ischemic heart disease and normal subjects

    International Nuclear Information System (INIS)

    Mahmood, N.; Naseem, T.; Mukhtar, F.; Basheer, R.

    2011-01-01

    Background: Coronary diseases appear to result from an overbalance between radical-generating, compared with radical-scavenging systems, a condition called as oxidative stress. Total antioxidant status (TAS) in human plasma reflects the balance between oxidants and antioxidants in each system. Bilirubin has been considered an antioxidant, with capacity to remove reactive species of oxygen. Present study tried to measure the total antioxidant status of first degree relatives of patients with IHD. Study also tried to evaluate the prognostic role of serum bilirubin in disease prevention or progression. Methods: Seventy five apparently healthy subjects in age group 20-50 years, comprising equal number of males and females, who were first degree relatives of ischemic heart disease patients, were included in the study. Family members were divided on the bases of their numbers, i.e., one family member (Group-A), 2 family members (Group-B) and more than 3 family members (Group-C). Study was cross sectional and carried out in a period of 6 months (Jun 2008-Jan 2009). Subjects with letter of consent were taken from general population. Seventy five healthy age matched people with no history of ischemic heart disease in family were taken as control. An overnight fasting blood sample was taken. Total antioxidant status was determined using a commercially available kit. Serum bilirubin was estimated by auto analyzer. Results: Family history of ischemic heart disease with serum bilirubin showed a significant negative correlation (p<0.05). But the values of TAS failed to show any significant correlation with the family history. It was observed that the value of serum bilirubin was decreased significantly (p<0.05) with an increased number of family members. Total antioxidant status failed to show any significant difference among all the three groups. Conclusion: Our data demonstrated that reduced serum levels of bilirubin were seen in people with a higher prevalence of coronary

  7. Sleep, Memory & Brain Rhythms.

    Science.gov (United States)

    Watson, Brendon O; Buzsáki, György

    2015-01-01

    Sleep occupies roughly one-third of our lives, yet the scientific community is still not entirely clear on its purpose or function. Existing data point most strongly to its role in memory and homeostasis: that sleep helps maintain basic brain functioning via a homeostatic mechanism that loosens connections between overworked synapses, and that sleep helps consolidate and re-form important memories. In this review, we will summarize these theories, but also focus on substantial new information regarding the relation of electrical brain rhythms to sleep. In particular, while REM sleep may contribute to the homeostatic weakening of overactive synapses, a prominent and transient oscillatory rhythm called "sharp-wave ripple" seems to allow for consolidation of behaviorally relevant memories across many structures of the brain. We propose that a theory of sleep involving the division of labor between two states of sleep-REM and non-REM, the latter of which has an abundance of ripple electrical activity-might allow for a fusion of the two main sleep theories. This theory then postulates that sleep performs a combination of consolidation and homeostasis that promotes optimal knowledge retention as well as optimal waking brain function.

  8. Circadian rhythms regulate amelogenesis.

    Science.gov (United States)

    Zheng, Li; Seon, Yoon Ji; Mourão, Marcio A; Schnell, Santiago; Kim, Doohak; Harada, Hidemitsu; Papagerakis, Silvana; Papagerakis, Petros

    2013-07-01

    Ameloblasts, the cells responsible for making enamel, modify their morphological features in response to specialized functions necessary for synchronized ameloblast differentiation and enamel formation. Secretory and maturation ameloblasts are characterized by the expression of stage-specific genes which follows strictly controlled repetitive patterns. Circadian rhythms are recognized as key regulators of the development and diseases of many tissues including bone. Our aim was to gain novel insights on the role of clock genes in enamel formation and to explore the potential links between circadian rhythms and amelogenesis. Our data shows definitive evidence that the main clock genes (Bmal1, Clock, Per1 and Per2) oscillate in ameloblasts at regular circadian (24 h) intervals both at RNA and protein levels. This study also reveals that the two markers of ameloblast differentiation i.e. amelogenin (Amelx; a marker of secretory stage ameloblasts) and kallikrein-related peptidase 4 (Klk4, a marker of maturation stage ameloblasts) are downstream targets of clock genes. Both, Amelx and Klk4 show 24h oscillatory expression patterns and their expression levels are up-regulated after Bmal1 over-expression in HAT-7 ameloblast cells. Taken together, these data suggest that both the secretory and the maturation stages of amelogenesis might be under circadian control. Changes in clock gene expression patterns might result in significant alterations of enamel apposition and mineralization. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Effects of Hyponatremia Normalization on the Short-Term Mortality and Rehospitalizations in Patients with Recent Acute Decompensated Heart Failure: A Retrospective Study

    Directory of Open Access Journals (Sweden)

    Renato De Vecchis

    2016-10-01

    Full Text Available Background: Several studies have shown that hyponatremia is associated with increased risk of rehospitalization and death in patients with heart failure. In these studies, chronic heart failure (CHF patients with persistent hyponatremia were compared only with CHF patients with a normal sodium level at hospital admission. Aims: In the present retrospective study, conducted in a cohort of patients with recent acute decompensated heart failure (ADHF, all with hyponatremia ascertained at the time of hospital admission, we aimed to evaluate the effect of the normalization of serum sodium on the composite endpoint of short-term rehospitalization and mortality. Methods: A retrospective study centered on medical records of patients hospitalized for ADHF in the period April 2013 to April 2016 was performed. Data regarding serum sodium measurements had to be collected from medical records of cardiology wards of two hospitals, and were then processed for statistical analysis. As an inclusion criterion for enrollment, patients had to be suffering from heart failure that had required at least one hospitalization. Moreover, they had to be suffering from a state of hyponatremia (serum sodium < 135 mEq/L at admission on the occasion of the index hospitalization. Patients with hyponatremia at admission were divided into two groups, one comprising patients with hyponatremia that persisted at the time of discharge (persistent hyponatremia and a second including patients who had achieved normalization of their serum sodium levels (serum Na+ ≥ 135 mEq/L during hospitalization until discharge. For both groups, the risk of mortality and rehospitalization during a 30-day follow-up was assessed. Results: One hundred and sixty CHF patients with various degrees of functional impairment were enrolled in the study. Among them, 56 (35% had persistent hyponatremia over the course of hospitalization. At multivariable Cox proportional-hazards regression analysis, the risk of

  10. Effects of exercise on circadian rhythms and mobility in aging Drosophila melanogaster

    OpenAIRE

    Rakshit, Kuntol; Wambua, Rebecca; Giebultowicz, Tomasz M.; Giebultowicz, Jadwiga M.

    2013-01-01

    Daily life functions such as sleep and feeding oscillate with circa 24 h period due to endogenous circadian rhythms generated by circadian clocks. Genetic or environmental disruption of circadian rhythms is associated with various aging-related phenotypes. Circadian rhythms decay during normal aging, and there is a need to explore strategies that could avert age-related changes in the circadian system. Exercise was reported to delay aging in mammals. Here, we investigated whether daily exerci...

  11. The Rhetorical Nature of Rhythm

    NARCIS (Netherlands)

    Balint, Mihaela; Dascalu, Mihai; Trausan-Matu, Stefan

    2017-01-01

    Up to date, linguistic rhythm has been studied for speech, but the rhythm of written texts has been merely recognized, and not analyzed or interpreted in connection to natural language tasks. We provide an extension of the textual rhythmic features we proposed in previous work, and

  12. Prognostic Value of Normal Perfusion but Impaired Left Ventricular Function in the Diabetic Heart on Quantitative Gated Myocardial Perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hwanjeong; Choi, Sehun; Han, Yeonhee [Research Institute of Chonbuk National Univ. Medical School and Hospitial, Jeonju (Korea, Republic of); Lee, Dong Soo; Lee, Hoyoung; Chung, Junekey [Seoul National Univ., Seoul (Korea, Republic of)

    2013-09-15

    This study aimed at identifying the predictive parameters on quantitative gated myocardial perfusion single-photon emission computed tomography (QG-SPECT) in diabetic patients with normal perfusion but impaired function. Methods Among the 533 consecutive diabetic patients, 379 patients with normal perfusion on rest Tl-201/dipyridamole-stress Tc-{sup 99m} sestamibi Gated SPECT were enrolled. Patients were grouped into those with normal post-stress left ventricular function (Group I) and those with impaired function (EF <50 or impaired regional wall motion, Group II). We investigated cardiac events and cause of death by chart review and telephone interview. Survival analysis and Cox proportional hazard model analysis were performed. Between the Group I and II, cardiac events as well as chest pain symptoms, smoking, diabetic complications were significantly different (P<0.05). On survival analysis, event free survival rate in Group II was significantly lower than in Group I (P=0.016). In univariate Cox proportional hazard analysis on overall cardiac event, Group (II over I), diabetic nephropathy, summed motion score (SMS), summed systolic thickening score (STS), numbers of abnormal segmental wall motion and systolic thickening predicted more cardiac events (P<0.05). Multivariate analysis showed that STS was the only independent predictor cardiac event. The functional parameter, especially summed systolic thickening score on QG-SPECT had prognostic values, despite normal perfusion, in predicting cardiac events in diabetic patients, and QG-SPECT provides clinically useful risk stratification in diabetic patients with normal perfusion.

  13. Management of atrial fibrillation in the setting of heart failure

    NARCIS (Netherlands)

    Crijns, HJGM; VandenBerg, MP; VanGelder, IC; VanVeldhuisen, DJ

    Heart failure is often complicated by atrial fibrillation. Once atrial fibrillation has started it further enhances heart failure due to uncontrolled rate with shortened filling time and provocation of tachycardiomyopathy. Absent atrial kick and irregularity of the ventricular rhythm also

  14. Analysis of Morphological Characteristics and Origins of Idiopathic Premature Ventricular Contractions Under a 12-Lead Electrocardiogram in Children with Structurally Normal Hearts.

    Science.gov (United States)

    Jiang, Jianbin; He, Yuee; Qiu, Huixian; Zhang, Yuanhai; Chu, Maoping; Li, Yuechun; Chen, Qi

    2017-10-21

    Up to 40% of healthy children have premature ventricular complexes or contractions (PVCs) detected with 24-hour Holter monitoring. We aimed to investigate the morphological characteristics and origins of idiopathic PVCs under a 12-lead electrocardiogram in children with structurally normal hearts. All asymptomatic monomorphic PVC patients with structurally normal hearts under 18 years of age were included in this retrospective study. Characteristics of PVCs in lead V 1 under a 12-lead electrocardiogram were classified as left bundle branch block (PVC-LBBB) or right bundle branch block (PVC-RBBB). According to limb leads, PVC-LBBB or PVC-RBBB was divided into: PVCs-LBBB type I; PVCs-LBBB type II; PVCs-RBBB type I; PVCs-RBBB type II; and PVCs-RBBB type III. Out of 178 PVC patients, 94 cases of PVCs-LBBB (PVCs-LBBB type I = 60; PVCs-LBBB type II = 34) and 84 cases of PVCs-RBBB (PVCs-RBBB type I = 3; PVCs-RBBB type II = 55; PVCs-RBBB type III = 26) were identified. The frequency of PVCs-LBBB type I increased with age and the frequency of PVCs-RBBB type II and III decreased with age. Among the children monitor tested, from 1 years old to 18 years old, PVCs originating from the left or right ventricular outflow tract gradually increased with age, while PVCs originating from the branch sources decreased with age.

  15. Recent Advances in Circadian Rhythms in Cardiovascular System

    Directory of Open Access Journals (Sweden)

    Lihong eChen

    2015-04-01

    Full Text Available Growing evidence shows that intrinsic circadian clocks are tightly related to cardiovascular functions. The diurnal changes in blood pressure and heart rate are well known circadian rhythms. Endothelial function, platelet aggregation and thrombus formation exhibit circadian changes as well. The onset of many cardiovascular diseases (CVDs or events, such as myocardial infarction, stroke, arrhythmia, and sudden cardiac death, also exhibits temporal trends. Furthermore, there is strong evidence from animal models and epidemiological studies showing that disruption of circadian rhythms is a significant risk factor for many CVDs, and the intervention of CVDs may have a time dependent effect. In this mini review, we summarized recent advances in our understanding of the relationship between circadian rhythm and cardiovascular physiology and diseases including blood pressure regulation and myocardial infarction.

  16. Ventricular arrhythmias in the absence of structural heart disease.

    Science.gov (United States)

    Prystowsky, Eric N; Padanilam, Benzy J; Joshi, Sandeep; Fogel, Richard I

    2012-05-15

    Ventricular arrhythmia (VA) in structurally normal hearts can be broadly considered under non-life-threatening monomorphic and life-threatening polymorphic rhythms. Monomorphic VA is classified on the basis of site of origin in the heart, and the most common areas are the ventricular outflow tracts and left ventricular fascicles. The morphology of the QRS complexes on electrocardiogram is an excellent tool to identify the site of origin of the rhythm. Although these arrhythmias are common and generally carry an excellent prognosis, rare sudden death events have been reported. Very frequent ventricular ectopy may also result in a cardiomyopathy in a minority of patients. Suppression of VA may be achieved using calcium-channel blockers, beta-adrenergic blockers, and class I or III antiarrhythmic drugs. Radiofrequency ablation has emerged as an excellent option to eliminate these arrhythmias, although certain foci including aortic cusps and epicardium may be technically challenging. Polymorphic ventricular tachycardia (VT) is rare and generally occurs in patients with genetic ion channel disorders including long QT syndrome, Brugada syndrome, catecholaminergic polymorphic VT, and short QT syndrome. Unlike monomorphic VT, these arrhythmic syndromes are associated with sudden death. While the cardiac gross morphology is normal, suggesting a structurally normal heart, abnormalities exist at the molecular level and predispose them to arrhythmias. Another fascinating area, idiopathic ventricular fibrillation and early repolarization syndrome, are undergoing research for a genetic basis. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  17. Modulation of the Rho/ROCK pathway in heart and lung after thorax irradiation reveals targets to improve normal tissue toxicity.

    Science.gov (United States)

    Monceau, Virginie; Pasinetti, Nadia; Schupp, Charlotte; Pouzoulet, Fred; Opolon, Paule; Vozenin, Marie-Catherine

    2010-11-01

    The medical options available to prevent or treat radiation-induced injury are scarce and developing effective countermeasures is still an open research field. In addition, more than half of cancer patients are treated with radiation therapy, which displays a high antitumor efficacy but can cause, albeit rarely, disabling long-term toxicities including radiation fibrosis. Progress has been made in the definition of molecular pathways associated with normal tissue toxicity that suggest potentially effective therapeutic targets. Targeting the Rho/ROCK pathway seems a promising anti-fibrotic approach, at least in the gut; the current study was performed to assess whether this target was relevant to the prevention and/or treatment of injury to the main thoracic organs, namely heart and lungs. First, we showed activation of two important fibrogenic pathways (Smad and Rho/ROCK) in response to radiation-exposure to adult cardiomyocytes; we extended these observations in vivo to the heart and lungs of mice, 15 and 30 weeks post-irradiation. We correlated this fibrogenic molecular imprint with alteration of heart physiology and long-term remodelling of pulmonary and cardiac histological structures. Lastly, cardiac and pulmonary radiation injury and bleomycin-induced pulmonary fibrosis were successfully modulated using Rho/ROCK inhibitors (statins and Y-27632) and this was associated with a normalization of fibrogenic markers. In conclusion, the present paper shows for the first time, activation of Rho/ROCK and Smad pathways in pulmonary and cardiac radiation-induced delayed injury. Our findings thereby reveal a safe and efficient therapeutic opportunity for the abrogation of late thoracic radiation injury, potentially usable either before or after radiation exposure; this approach is especially attractive in (1) the radiation oncology setting, as it does not interfere with prior anti-cancer treatment and in (2) radioprotection, as applicable to the treatment of established

  18. Modulation of the ρ/rock pathway in heart and lung after thorax irradiation reveals targets to improve normal tissue toxicity

    International Nuclear Information System (INIS)

    Monceau, V.; Pasinetti, N.; Schupp, C.; Pouzoulet, F.; Opolon, P.; Vozenin, M.C.

    2010-01-01

    The medical options available to prevent or treat radiation-induced injury are scarce and developing effective countermeasures is still an open research field. In addition, more than half of cancer patients are treated with radiation therapy, which displays a high antitumor efficacy but can cause, albeit rarely, disabling long-term toxicities including radiation fibrosis. Progress has been made in the definition of molecular pathways associated with normal tissue toxicity that suggest potentially effective therapeutic targets. Targeting the Rho/ROCK pathway seems a promising anti-fibrotic approach, at least in the gut; the current study was performed to assess whether this target was relevant to the prevention and/or treatment of injury to the main thoracic organs, namely heart and lungs. First, we showed activation of two important fibro-genic pathways (Smad and Rho/ROCK) in response to radiation-exposure to adult cardio-myocytes; we extended these observations in vivo to the heart and lungs of mice, 15 and 30 weeks post-irradiation. We correlated this fibro-genic molecular imprint with alteration of heart physiology and long-term remodelling of pulmonary and cardiac histological structures. Lastly, cardiac and pulmonary radiation injury and bleomycin-induced pulmonary fibrosis were successfully modulated using Rho/ROCK inhibitors (statins and Y-27632) and this was associated with a normalization of fibro-genic markers. In conclusion, the present paper shows for the first time, activation of Rho/ROCK and Smad pathways in pulmonary and cardiac radiation-induced delayed injury. Our findings thereby reveal a safe and efficient therapeutic opportunity for the abrogation of late thoracic radiation injury, potentially usable either before or after radiation exposure; this approach is especially attractive in (1) the radiation oncology setting, as it does not interfere with prior anti-cancer treatment and in (2) radioprotection, as applicable to the treatment of

  19. XYLITOL IMPROVES ANTI-OXIDATIVE DEFENSE SYSTEM IN SERUM, LIVER, HEART, KIDNEY AND PANCREAS OF NORMAL AND TYPE 2 DIABETES MODEL OF RATS.

    Science.gov (United States)

    Chukwuma, Chika Ifeanyi; Islam, Shahidul

    2017-05-01

    The present study investigated the anti-oxidative effects of xylitol both in vitro and in vivo in normal and type 2 diabetes (T2D) rat model. Free radical scavenging and ferric reducing potentials of different concentrations of xylitol were investigated in vitro. For in vivo study, six weeks old male Sprague-Dawley rats were divided into four groups, namely: Normal Control (NC), Diabetic Control (DBC), Normal Xylitol (NXYL) and Diabetic Xylitol (DXYL). T2D was induced in the DBC and DXYL groups. After the confirmation of diabetes, a 10% xylitol solution was supplied instead of drinking water to NXYL and DXYL, while normal drinking water was supplied to NC and DBC ad libitum. After five weeks intervention period, the animals were sacri- ficed and thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) concentrations as well as superoxide dismutase, catalase glutathione reductase and glutathione peroxidase activities were determined in the liver, heart, kidney, pancreatic tissues and serum samples. Xylitol exhibited significant (p foods and food products.

  20. Detection of myocardial 123I-BMIPP distribution abnormality in patients with ischemic heart disease based on normal data file in Bull's-eye polar map

    International Nuclear Information System (INIS)

    Takahashi, Nobukazu; Ishida, Yoshio; Hirose, Yoshiaki; Kawano, Shigeo; Fukuoka, Syuji; Hayashida, Kohei; Takamiya, Makoto; Nonogi, Hiroshi

    1995-01-01

    Visual interpretation of 123 I-BMIPP (BMIPP) myocardial images has difficulties in detecting mild reduction in tracer uptake. We studied the significance of the objective assessment of myocardial BMIPP maldistributions at rest by using a Bull's-eye map and its normal data file for detecting ischemic heart disease. Twenty nine patients, 15 with prior myocardial infarction and 14 with effort angina were studied. The initial 15-min BMIPP image was evaluated by visual analysis and by generating the extent Bull's-eye map which exhibits regions with reduced % uptake under mean-2SD of 10 normal controls. The sensitivity for determining coronary lesions in non-infarcted myocardial regions with the extent map was superior to that with visual analysis (67% vs. 33%). In the regions supplied by the stenotic coronary artery, those which showed visually negative but positive in the map and which showed positive in both had higher incidence of wall motion abnormalities and severe coronary stenosis than those with normal findings in both. These results suggest that the objective assessment based on the normal data file in a Bull's-eye polar map is clinically important for improving the limitation or the visual interpretation in 123 I-BMIPP imaging. (author)

  1. Effect of mental challenge induced by movie clips on action potential duration in normal human subjects independent of heart rate.

    Science.gov (United States)

    Child, Nicholas; Hanson, Ben; Bishop, Martin; Rinaldi, Christopher A; Bostock, Julian; Western, David; Cooklin, Michael; O'Neil, Mark; Wright, Matthew; Razavi, Reza; Gill, Jaswinder; Taggart, Peter

    2014-06-01

    Mental stress and emotion have long been associated with ventricular arrhythmias and sudden death in animal models and humans. The effect of mental challenge on ventricular action potential duration (APD) in conscious healthy humans has not been reported. Activation recovery intervals measured from unipolar electrograms as a surrogate for APD (n=19) were recorded from right and left ventricular endocardium during steady-state pacing, whilst subjects watched an emotionally charged film clip. To assess the possible modulating role of altered respiration on APD, the subjects then repeated the same breathing pattern they had during the stress, but without the movie clip. Hemodynamic parameters (mean, systolic, and diastolic blood pressure, and rate of pressure increase) and respiration rate increased during the stressful part of the film clip (P=0.001). APD decreased during the stressful parts of the film clip, for example, for global right ventricular activation recovery interval at end of film clip 193.8 ms (SD, 14) versus 198.0 ms (SD, 13) during the matched breathing control (end film left ventricle 199.8 ms [SD, 16] versus control 201.6 ms [SD, 15]; P=0.004). Respiration rate increased during the stressful part of the film clip (by 2 breaths per minute) and was well matched in the respective control period without any hemodynamic or activation recovery interval changes. Our results document for the first time direct recordings of the effect of a mental challenge protocol on ventricular APD in conscious humans. The effect of mental challenge on APD was not secondary to emotionally induced altered respiration or heart rate. © 2014 American Heart Association, Inc.

  2. Circadian rhythm and sleep influences on digestive physiology and disorders

    Directory of Open Access Journals (Sweden)

    Vaughn BV

    2014-09-01

    Full Text Available Bradley V Vaughn, Sean Rotolo, Heidi L Roth Division of Sleep Medicine, Department of Neurology, University of North Carolina School of Medicine, Chapel Hill, NC, USA Abstract: Circadian rhythms and sleep influence a variety of physiological functions, including the digestive system. The digestive system also has intrinsic rhythms that interact dynamically with circadian rhythms. New advances in understanding the interaction of these rhythms and sleep provide the prospect of evaluating their role in normal physiology and the link of their disruption to pathological conditions. Recent work has demonstrated that sleep and circadian factors influence appetite, nutrient absorption, and metabolism. Disruption of sleep and circadian rhythms may increase vulnerability to digestive disorders, including reflux, ulcers, inflammatory bowel issues, irritable bowel disease, and gastrointestinal cancer. As our knowledge of the link between circadian timing and gastrointestinal physiology grows, so do our opportunities to provide promising diagnostic and therapeutic approaches for gastrointestinal disorders. Keywords: digestion, digestive diseases, gastrointestinal reflux, sleep, circadian rhythm 

  3. Weightlessness and Cardiac Rhythm Disorders: Current Knowledge from Space Flight and Bed-Rest Studies

    International Nuclear Information System (INIS)

    Caiani, Enrico G.; Martin-Yebra, Alba; Landreani, Federica; Bolea, Juan; Laguna, Pablo; Vaïda, Pierre

    2016-01-01

    Isolated episodes of heart rhythm disorders have been reported during 40 years of space flight, triggering research to evaluate the risk of developing life-threatening arrhythmias induced by prolonged exposure to weightlessness. In fact, these events could compromise astronaut performance during exploratory missions, as well as pose at risk the astronaut health, due to limited options of care on board the International Space Station. Starting from original observations, this mini review will explore the latest research in this field, considering results obtained both during space flight and on Earth, the latter by simulating long-term exposure to microgravity by head-down bed rest maneuver in order to elicit cardiovascular deconditioning on normal volunteers.

  4. Weightlessness and Cardiac Rhythm Disorders: Current Knowledge from Space Flight and Bed-Rest Studies

    Energy Technology Data Exchange (ETDEWEB)

    Caiani, Enrico G. [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan (Italy); Martin-Yebra, Alba [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan (Italy); Instituto de Investigación en Ingeniería de Aragón (I3A), Universidad de Zaragoza, Zaragoza (Spain); Landreani, Federica [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan (Italy); Bolea, Juan; Laguna, Pablo [Instituto de Investigación en Ingeniería de Aragón (I3A), Universidad de Zaragoza, Zaragoza (Spain); Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza (Spain); Vaïda, Pierre, E-mail: enrico.caiani@polimi.it [École Nationale Supérieure de Cognitique, Institut Polytechnique de Bordeaux, Université de Bordeaux, Bordeaux (France)

    2016-08-23

    Isolated episodes of heart rhythm disorders have been reported during 40 years of space flight, triggering research to evaluate the risk of developing life-threatening arrhythmias induced by prolonged exposure to weightlessness. In fact, these events could compromise astronaut performance during exploratory missions, as well as pose at risk the astronaut health, due to limited options of care on board the International Space Station. Starting from original observations, this mini review will explore the latest research in this field, considering results obtained both during space flight and on Earth, the latter by simulating long-term exposure to microgravity by head-down bed rest maneuver in order to elicit cardiovascular deconditioning on normal volunteers.

  5. Dissipative structures and biological rhythms

    Science.gov (United States)

    Goldbeter, Albert

    2017-10-01

    Sustained oscillations abound in biological systems. They occur at all levels of biological organization over a wide range of periods, from a fraction of a second to years, and with a variety of underlying mechanisms. They control major physiological functions, and their dysfunction is associated with a variety of physiological disorders. The goal of this review is (i) to give an overview of the main rhythms observed at the cellular and supracellular levels, (ii) to briefly describe how the study of biological rhythms unfolded in the course of time, in parallel with studies on chemical oscillations, (iii) to present the major roles of biological rhythms in the control of physiological functions, and (iv) the pathologies associated with the alteration, disappearance, or spurious occurrence of biological rhythms. Two tables present the main examples of cellular and supracellular rhythms ordered according to their period, and their role in physiology and pathophysiology. Among the rhythms discussed are neural and cardiac rhythms, metabolic oscillations such as those occurring in glycolysis in yeast, intracellular Ca++ oscillations, cyclic AMP oscillations in Dictyostelium amoebae, the segmentation clock that controls somitogenesis, pulsatile hormone secretion, circadian rhythms which occur in all eukaryotes and some bacteria with a period close to 24 h, the oscillatory dynamics of the enzymatic network driving the cell cycle, and oscillations in transcription factors such as NF-ΚB and tumor suppressors such as p53. Ilya Prigogine's concept of dissipative structures applies to temporal oscillations and allows us to unify within a common framework the various rhythms observed at different levels of biological organization, regardless of their period and underlying mechanism.

  6. How Two Players Negotiate Rhythm in a Shared Rhythm Game

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa

    2012-01-01

    from each other. Video analysis of user interaction shines light upon how users engaged in a rhythmical relationship, and interviews give information about the user experience in terms of the game play and user collaboration. Based on the findings in this paper we propose design guidelines......In a design and working prototype of a shared music interface eleven teams of two people were to collaborate about filling in holes with tones and beats in an evolving ground rhythm. The hypothesis was that users would tune into each other and have sections of characteristic rhythmical...... relationships that related to the ground rhythm. Results from interaction data show that teams did find a mutual rhythm, and that they were able to keep this rhythm for a while and/or over several small periods. Results also showed that two players engaged in very specific rhythmical relationships that differed...

  7. 4D flow MRI assessment of right atrial flow patterns in the normal heart - influence of caval vein arrangement and implications for the patent foramen ovale.

    Directory of Open Access Journals (Sweden)

    Jehill D Parikh

    Full Text Available To investigate atrial flow patterns in the normal adult heart, to explore whether caval vein arrangement and patency of the foramen ovale (PFO may be associated with flow pattern.Time-resolved, three-dimensional velocity encoded magnetic resonance imaging (4D flow was employed to assess atrial flow patterns in thirteen healthy subjects (6 male, 40 years, range 25-50 and thirteen subjects (6 male, 40 years, range 21-50 with cryptogenic stroke and patent foramen ovale (CS-PFO. Right atrial flow was defined as vortical, helico-vortical, helical and multiple vortices. Time-averaged and peak systolic and diastolic flows in the caval and pulmonary veins and their anatomical arrangement were compared.A spectrum of right atrial flow was observed across the four defined categories. The right atrial flow patterns were strongly associated with the relative position of the caval veins. Right atrial flow patterns other than vortical were more common (p = 0.015 and the separation between the superior and inferior vena cava greater (10±5mm versus 3±3mm, p = 0.002 in the CS-PFO group. In the left atrium all subjects except one had counter-clockwise vortical flow. Vortex size varied and was associated with left lower pulmonary vein flow (systolic r = 0.61, p = 0.001, diastolic r = 0.63 p = 0.002. A diastolic vortex was less common and time-averaged left atrial velocity was greater in the CS-PFO group (17±2cm/sec versus 15±1, p = 0.048. One CS-PFO subject demonstrated vortical retrograde flow in the descending aortic arch; all other subjects had laminar descending aortic flow.Right atrial flow patterns in the normal heart are heterogeneous and are associated with the relative position of the caval veins. Patterns, other than 'typical' vortical flow, are more prevalent in the right atrium of those with cryptogenic stroke in the context of PFO. Left atrial flow patterns are more homogenous in normal hearts and show a relationship with flow arising from the left

  8. Learning by joining the rhythm

    DEFF Research Database (Denmark)

    Lund, Ole; Ravn, Susanne; Christensen, Mette Krogh

    2012-01-01

    This article aims to explore how a joint rhythm is learned. The exploration is based on a combination of a case study of training in elite rowing and theoretical considerations concerning mutual incorporation of skills in learning. In 2009 Juliane and Anne start to row the double sculler together....... The two rowers’ aim is to be among the exclusive group of teams that qualify for the Olympic Games three years later. However Anne is not a rower, and has to be apprenticed by Juliane, who is an experienced elite rower. One important learning goal in the apprenticeship is to find a good joint rhythm......, to be able to put optimal effort into the rowing. Thus the apprenticeship is about developing a sense for a good rhythm in Anne which corresponds to Juliane’s fine-grained sense of what a good rhythm should feel like. Our study suggests that apprenticeship learning has to be understood as an embodied...

  9. Sympathetic rhythms and nervous integration.

    Science.gov (United States)

    Gilbey, Michael P

    2007-04-01

    1. The present review focuses on some of the processes producing rhythms in sympathetic nerves influencing cardiovascular functions and considers their potential relevance to nervous integration. 2. Two mechanisms are considered that may account for rhythmic sympathetic discharges. First, neuronal elements of peripheral or central origin produce rhythmic activity by phasically exciting and/or inhibiting neurons within central sympathetic networks. Second, rhythms arise within central sympathetic networks. Evidence is considered that indicates the operation of both mechanisms; the first in muscle and the second in skin sympathetic vasoconstrictor networks. 3. Sympathetic activity to the rat tail, a model for the nervous control of skin circulation, is regulated by central networks involved in thermoregulation and those associated with fear and arousal. In an anaesthetized preparation, activity displays an apparently autonomous rhythm (T-rhythm; 0.4-1.2 Hz) and the level of activity can be manipulated by regulating core body temperature. This model has been used to study rhythm generation in central sympathetic networks and possible functional relevance. 4. A unique insight provided by the T rhythm, into possible physiological function(s) underlying rhythmic sympathetic discharges is that the activity of single sympathetic post-ganglionic neurons within a population innervating the same target can have different rhythm frequencies. Therefore, the graded and dynamic entrainment of the rhythms by inputs, such as central respiratory drive and/or lung inflation-related afferent activity, can produce graded and dynamic synchronization of sympathetic discharges. The degree of synchronization may influence the efficacy of transmission in a target chain of excitable cells. 5. The T-rhythm may be generated within the spinal cord because the intrathecal application of 5-hydroxytryptamine at the L1 level of the spinal cord of a rat spinalized at T10-T11 produces a T-like rhythm

  10. Prevalence of symptomatic heart failure with reduced and with normal ejection fraction in an elderly general population-the CARLA study.

    Directory of Open Access Journals (Sweden)

    Daniel Tiller

    Full Text Available BACKGROUND/OBJECTIVES: Chronic heart failure (CHF is one of the most important public health concerns in the industrialized world having increasing incidence and prevalence. Although there are several studies describing the prevalence of heart failure with reduced ejection fraction (HFREF and heart failure with normal ejection fraction (HFNEF in selected populations, there are few data regarding the prevalence and the determinants of symptomatic heart failure in the general population. METHODS: Cross-sectional data of a population-based German sample (1,779 subjects aged 45-83 years were analyzed to determine the prevalence and determinants of chronic SHF and HFNEF defined according to the European Society of Cardiology using symptoms, echocardiography and serum NT-proBNP. Prevalence was age-standardized to the German population as of December 31st, 2005. RESULTS: The overall age-standardized prevalence of symptomatic CHF was 7.7% (95%CI 6.0-9.8 for men and 9.0% (95%CI 7.0-11.5 for women. The prevalence of CHF strongly increased with age from 3.0% among 45-54- year-old subjects to 22.0% among 75-83- year-old subjects. Symptomatic HFREF could be shown in 48% (n = 78, symptomatic HFNEF in 52% (n = 85 of subjects with CHF. The age-standardized prevalence of HFREF was 3.8 % (95%CI 2.4-5.8 for women and 4.6 % (95%CI 3.6-6.3 for men. The age-standardized prevalence of HFNEF for women and men was 5.1 % (95%CI 3.8-7.0 and 3.0 % (95%CI 2.1-4.5, respectively. Persons with CHF were more likely to have hypertension (PR = 3.4; 95%CI 1.6-7.3 or to have had a previous myocardial infarction (PR = 2.5, 95%CI 1.8-3.5. CONCLUSION: The prevalence of symptomatic CHF appears high in this population compared with other studies. While more women were affected by HFNEF than men, more male subjects suffered from HFREF. The high prevalence of symptomatic CHF seems likely to be mainly due to the high prevalence of cardiovascular risk factors in this population.

  11. International normalized ratio self-management lowers the risk of thromboembolic events after prosthetic heart valve replacement.

    Science.gov (United States)

    Eitz, Thomas; Schenk, Soren; Fritzsche, Dirk; Bairaktaris, Andreas; Wagner, Otto; Koertke, Heinrich; Koerfer, Reiner

    2008-03-01

    Although prosthetic valves are durable and easy to implant, the need for lifetime warfarin-based anticoagulation restricts their exclusive usage. We investigated if anticoagulation self-management improves outcome in a single-center series. Between 1994 and 1998, 765 patients with prosthetic valve replacements were prospectively enrolled and randomized to receive conventional anticoagulation management by their primary physician (group 1, n = 295) or to pursue anticoagulation self-management (group 2, n = 470). A study head office was implemented to coordinate and monitor anticoagulation protocols, international normalized ratios (INR), and adverse events. Patients were instructed on how to obtain and test their own blood samples and to adjust warfarin dosages according to the measured INR (target range, 2.5 to 4). Mean INR values were slightly yet significantly smaller in group 1 than in group 2 (2.8 +/- 0.7 vs 3.0 +/- .6, p events were similar in both groups. Time-related multivariate analysis identified INR self-management and higher INR as independent predictors for better outcome. Anticoagulation self-management can improve INR profiles up to 2 years after prosthetic valve replacement and reduce adverse events. Current indications of prosthetic rather than biologic valve implantations may be extended if the benefit of INR self-management is shown by future studies with longer follow-up.

  12. Revisiting the slow force response: the role of the PKG signaling pathway in the normal and the ischemic heart.

    Science.gov (United States)

    Castro-Ferreira, Ricardo; Neves, João Sérgio; Ladeiras-Lopes, Ricardo; Leite-Moreira, André M; Neiva-Sousa, Manuel; Almeida-Coelho, João; Ferreira-Martins, João; F Leite-Moreira, Adelino

    2014-09-01

    The myocardial response to acute stretch consists of a two-phase increase in contractility: an acute increase by the Frank-Starling mechanism and a gradual and time-dependent increase in force generated known as the slow force response (SFR). The SFR is actively modulated by different signaling pathways, but the role of protein kinase G (PKG) signaling is unknown. In this study we aim to characterize the role of the PKG signaling pathway in the SFR under normal and ischemic conditions. Rabbit papillary muscles were stretched from 92 to 100% of maximum length (Lmax) under basal conditions, in the absence (1) or presence of: a PKG agonist (2) and a PKG inhibitor (3); under ischemic conditions in the absence (4) or presence of: a PKG agonist (5); a nitric oxide (NO) donor (6) and a phosphodiesterase 5 (PDE5) inhibitor (7). Under normoxia, the SFR was significantly attenuated by inhibition of PKG and remained unaltered with PKG activation. Ischemia induced a progressive decrease in myocardial contractility after stretch. Neither the PKG agonist nor the NO donor altered the myocardial response to stretch under ischemic conditions. However, the use of a PDE5 inhibitor in ischemia partially reversed the progressive deterioration in contractility. PKG activity is essential for the SFR. During ischemia, a progressive decline in the force is observed in response to acute myocardial stretch. This dysfunctional response can be partially reversed by the use of PDE5 inhibitors. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  13. Peripartum haemodynamic status of bitches with normal birth or dystocia.

    Science.gov (United States)

    Lúcio, C F; Silva, L C G; Rodrigues, J A; Veiga, G A L; Vannucchi, C I

    2009-07-01

    There has been limited investigation of parturition in the bitch and there is little information published on clinical and obstetrical examination other than opinion and anecdote. While there are substantial data on haemodynamic and vascular changes during normal parturition in humans, little is known about the physiological events in the dog. This study was aimed at maternal haemodynamic changes occurring during normal parturition and to investigate how these were modified in bitches with dystocia (DYST) treated either medically or via assisted delivery and caesarean operation. Three groups of 10 bitches were investigated; those with normal parturition, those with DYST corrected by manipulative assistance or caesarean operation and those with uterine inertia treated by oxytocin administration. Heart rate, systolic and diastolic blood pressure, electrocardiogram and blood glucose concentration were measured pre-partum, intra-partum, immediately after parturition and 1 h later. Heart rate was high at all times throughout the study and the majority of bitches had normal sinus rhythm. Blood pressure was generally within the normal range, and although systolic and diastolic blood pressure was highest during the intra-partum period and sometimes during the immediate post-partum period, there were no significant differences between groups. All bitches had blood glucose concentrations within the normal range throughout the study although pre-partum concentrations were statistically lower than many of the other time periods. The study provides useful physiological data that will facilitate monitoring and clinical management of bitches throughout normal parturition and DYST.

  14. Circadian Rhythm Connections to Oxidative Stress: Implications for Human Health

    Science.gov (United States)

    Wilking, Melissa; Ndiaye, Mary; Mukhtar, Hasan

    2013-01-01

    Abstract Significance: Oxygen and circadian rhythmicity are essential in a myriad of physiological processes to maintain homeostasis, from blood pressure and sleep/wake cycles, down to cellular signaling pathways that play critical roles in health and disease. If the human body or cells experience significant stress, their ability to regulate internal systems, including redox levels and circadian rhythms, may become impaired. At cellular as well as organismal levels, impairment in redox regulation and circadian rhythms may lead to a number of adverse effects, including the manifestation of a variety of diseases such as heart diseases, neurodegenerative conditions, and cancer. Recent Advances: Researchers have come to an understanding as to the basics of the circadian rhythm mechanism, as well as the importance of the numerous species of oxidative stress components. The effects of oxidative stress and dysregulated circadian rhythms have been a subject of intense investigations since they were first discovered, and recent investigations into the molecular mechanisms linking the two have started to elucidate the bases of their connection. Critical Issues: While much is known about the mechanics and importance of oxidative stress systems and circadian rhythms, the front where they interact has had very little research focused on it. This review discusses the idea that these two systems are together intricately involved in the healthy body, as well as in disease. Future Directions: We believe that for a more efficacious management of diseases that have both circadian rhythm and oxidative stress components in their pathogenesis, targeting both systems in tandem would be far more successful. Antioxid. Redox Signal. 19, 192–208 PMID:23198849

  15. Telemedicine-guided, very low-dose international normalized ratio self-control in patients with mechanical heart valve implants.

    Science.gov (United States)

    Koertke, Heinrich; Zittermann, Armin; Wagner, Otto; Secer, Songuel; Sciangula, Alfonso; Saggau, Werner; Sack, Falk-Udo; Ennker, Jürgen; Cremer, Jochen; Musumeci, Francesco; Gummert, Jan F

    2015-06-01

    To study in patients performing international normalized ratio (INR) self-control the efficacy and safety of an INR target range of 1.6-2.1 for aortic valve replacement (AVR) and 2.0-2.5 for mitral valve replacement (MVR) or double valve replacement (DVR). In total, 1304 patients undergoing AVR, 189 undergoing MVR and 78 undergoing DVR were randomly assigned to low-dose INR self-control (LOW group) (INR target range, AVR: 1.8-2.8; MVR/DVR: 2.5-3.5) or very low-dose INR self-control once a week (VLO group) and twice a week (VLT group) (INR target range, AVR: 1.6-2.1; MVR/DVR: 2.0-2.5), with electronically guided transfer of INR values. We compared grade III complications (major bleeding and thrombotic events; primary end-points) and overall mortality (secondary end-point) across the three treatment groups. Two-year freedom from bleedings in the LOW, VLO, and VLT groups was 96.3, 98.6, and 99.1%, respectively (P = 0.008). The corresponding values for thrombotic events were 99.0, 99.8, and 98.9%, respectively (P = 0.258). The risk-adjusted composite of grade III complications was in the per-protocol population (reference: LOW-dose group) as follows: hazard ratio = 0.307 (95% CI: 0.102-0.926; P = 0.036) for the VLO group and = 0.241 (95% CI: 0.070-0.836; P = 0.025) for the VLT group. The corresponding values of 2-year mortality were = 1.685 (95% CI: 0.473-5.996; P = 0.421) for the VLO group and = 4.70 (95% CI: 1.62-13.60; P = 0.004) for the VLT group. Telemedicine-guided very low-dose INR self-control is comparable with low-dose INR in thrombotic risk, and is superior in bleeding risk. Weekly testing is sufficient. Given the small number of MVR and DVR patients, results are only valid for AVR patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  16. Impact of chronodisruption during primate pregnancy on the maternal and newborn temperature rhythms.

    Directory of Open Access Journals (Sweden)

    María Serón-Ferré

    Full Text Available Disruption of the maternal environment during pregnancy is a key contributor to offspring diseases that develop in adult life. To explore the impact of chronodisruption during pregnancy in primates, we exposed pregnant capuchin monkeys to constant light (eliminating the maternal melatonin rhythm from the last third of gestation to term. Maternal temperature and activity circadian rhythms were assessed as well as the newborn temperature rhythm. Additionally we studied the effect of daily maternal melatonin replacement during pregnancy on these rhythms. Ten pregnant capuchin monkeys were exposed to constant light from 60% of gestation to term. Five received a daily oral dose of melatonin (250 µg kg/body weight at 1800 h (LL+Mel and the other five a placebo (LL. Six additional pregnant females were maintained in a 14∶10 light:dark cycles and their newborns were used as controls (LD. Rhythms were recorded 96 h before delivery in the mother and at 4-6 days of age in the newborn. Exposure to constant light had no effect on the maternal body temperature rhythm however it delayed the acrophase of the activity rhythm. Neither rhythm was affected by melatonin replacement. In contrast, maternal exposure to constant light affected the newborn body temperature rhythm. This rhythm was entrained in control newborns whereas LL newborns showed a random distribution of the acrophases over 24-h. In addition, mean temperature was decreased (34.0±0.6 vs 36.1±0.2°C, in LL and control, respectively P<0.05. Maternal melatonin replacement during pregnancy re-synchronized the acrophases and restored mean temperature to the values in control newborns. Our findings demonstrate that prenatal melatonin is a Zeitgeber for the newborn temperature rhythm and supports normal body temperature maintenance. Altogether these prenatal melatonin effects highlight the physiological importance of the maternal melatonin rhythm during pregnancy for the newborn primate.

  17. Normal sleep and its neurophysiological regulation

    NARCIS (Netherlands)

    Hofman, W.F.; Talamini, L.M.; Watson, R.R.

    2015-01-01

    Normal sleep consists of two states: NREM (light and deep sleep) and REM, alternating in a cyclical pattern. The sleep/wake rhythm is regulated by two processes: the sleep propensity, building up during wake, and the circadian rhythm, imposed by the suprachiasmatic nucleus. The arousal pathways in

  18. Analysis and classification of ECG-waves and rhythms using circular statistics and vector strength

    Directory of Open Access Journals (Sweden)

    Janßen Jan-Dirk

    2017-09-01

    Full Text Available The most common way to analyse heart rhythm is to calculate the RR-interval and the heart rate variability. For further evaluation, descriptive statistics are often used. Here we introduce a new and more natural heart rhythm analysis tool that is based on circular statistics and vector strength. Vector strength is a tool to measure the periodicity or lack of periodicity of a signal. We divide the signal into non-overlapping window segments and project the detected R-waves around the unit circle using the complex exponential function and the median RR-interval. In addition, we calculate the vector strength and apply circular statistics as wells as an angular histogram on the R-wave vectors. This approach enables an intuitive visualization and analysis of rhythmicity. Our results show that ECG-waves and rhythms can be easily visualized, analysed and classified by circular statistics and vector strength.

  19. Thyroid and the Heart

    Directory of Open Access Journals (Sweden)

    A Karas

    2009-09-01

    Full Text Available The cardiovascular signs and symptoms of thyroid disease are some of the most clinically relevant findings that accompany both hyperthyroidism and hypothyroidism. On the basis of the understanding of the mechanisms of thyroid hormone action on the heart and cardiovascular system, it is possible to explain the changes in cardiac output, cardiac contractility, blood pressure and rhythm disturbances that result from thyroid dysfunction. In the present review will integrate what is known about the mechanisms of thyroid hormone action on the heart and the alterations in thyroid hormone metabolism that accompany chronic congestive heart failure.

  20. Sleep and circadian rhythm disruption in neuropsychiatric illness.

    Science.gov (United States)

    Jagannath, Aarti; Peirson, Stuart N; Foster, Russell G

    2013-10-01

    Sleep and circadian rhythm disruption (SCRD) is a common feature in many neuropsychiatric diseases including schizophrenia, bipolar disorder and depression. Although the precise mechanisms remain unclear, recent evidence suggests that this comorbidity is not simply a product of medication or an absence of social routine, but instead reflects commonly affected underlying pathways and mechanisms. For example, several genes intimately involved in the generation and regulation of circadian rhythms and sleep have been linked to psychiatric illness. Further, several genes linked to mental illness have recently been shown to also play a role in normal sleep and circadian behaviour. Here we describe some of the emerging common mechanisms that link circadian rhythms, sleep and SCRD in severe mental illnesses. A deeper understanding of these links will provide not only a greater understanding of disease mechanisms, but also holds the promise of novel avenues for therapeutic intervention. Copyright © 2013. Published by Elsevier Ltd.

  1. Current Conceptual Challenges in the Study of Rhythm Processing Deficits

    Directory of Open Access Journals (Sweden)

    Pauline eTranchant

    2015-06-01

    Full Text Available Interest in the study of rhythm processing deficits (RPD is currently growing in the cognitive neuroscience community, as this type of investigation constitutes a powerful tool for the understanding of normal rhythm processing. Because this field is in its infancy, it still lacks a common conceptual vocabulary to facilitate effective communication between different researchers and research groups. In this commentary, we provide a brief review of recent reports of RPD through the lens of one important empirical issue: the method by which beat perception is measured, and the consequences of method selection for the researcher’s ability to specify which mechanisms are impaired in RPD. This critical reading advocates for the importance of matching measurement tools to the putative neurocognitive mechanisms under study, and reveals the need for effective and specific assessments of the different aspects of rhythm perception and synchronization.

  2. A Low-Normal Free Triiodothyronine Level Is Associated with Adverse Prognosis in Euthyroid Patients with Heart Failure Receiving Cardiac Resynchronization Therapy.

    Science.gov (United States)

    Chen, Yu-Yang; Shu, Xiao-Rong; Su, Zi-Zhuo; Lin, Rong-Jie; Zhang, Hai-Feng; Yuan, Wo-Liang; Wang, Jing-Feng; Xie, Shuang-Lun

    2017-12-12

    Thyroid dysfunction is prevalent in patients with heart failure (HF) and hypothyroidism is related to the adverse prognosis of HF subjects receiving cardiac resynchronization therapy (CRT). We aim to investigate whether low-normal free triiodothyronine (fT3) level is related to CRT response and the prognosis of euthyroid patients with HF after CRT implantation.One hundred and thirteen euthyroid patients who received CRT therapy without previous thyroid disease and any treatment affecting thyroid hormones were enrolled. All of patients were evaluated for cardiac function and thyroid hormones (serum levels of fT3, free thyroxine [fT4] and thyroid-stimulating hormone [TSH]). The end points were overall mortality and hospitalization for HF worsening. During a follow-up period of 39 ± 3 weeks, 36 patients (31.9%) died and 45 patients (39.8%) had hospitalization for HF exacerbation. A higher rate of NYHA III/IV class and a lower fT3 level were both observed in death group and HF event group. Multivariate Cox regression analyses disclosed that a lower-normal fT3 level (HR = 0.648, P = 0.009) and CRT response (HR = 0.441, P = 0.001) were both independent predictors of overall mortality. In addition, they were also both related to HF re-hospitalization event (P < 0.01 for both). Patients with fT3 < 3.00 pmol/L had a significantly higher overall mortality than those with fT3 ≥ 3.00 pmol/L (P = 0.027). Meanwhile, a higher HF hospitalization event rate was also found in patients with fT3 < 3.00 pmol/L (P < 0.001).A lower-normal fT3 level is correlated with a worse cardiac function an adverse prognosis in euthyroid patients with HF after CRT implantation.

  3. The normal electrocardiogram of four species of conscious raptors.

    Science.gov (United States)

    Talavera, J; Guzmán, M J; del Palacio, M J Fernández; Albert, A P; Bayón, A

    2008-02-01

    The aim of this study was to describe normal ECG patterns and values in four species of conscious raptors (Eurasian kestrel, Griffon vulture, Little owl, and Eurasian Eagle owl). Electrocardiograms were carried out in 75 conscious birds belonging to four species of raptors. Lead II waveforms were analysed to determine amplitudes and durations of waves and intervals. Morphologic patterns of P-QRS-T deflections were analysed in the six limb leads. Rhythm, heart rate, mean electrical axis, presence of Ta wave, ST slurring, and P-on-T phenomenon were also studied. The influence of species, body weight and heart rate in electrocardiographic variables were statistically analysed (P raptors that can be used to establish comparisons for clinical purposes.

  4. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F.; van der Veen, Daan R.; O’ Donnell, Aidan J.; Cumnock, Katherine; Schneider, David; Pain, Arnab; Subudhi, Amit; Ramaprasad, Abhinay; Rund, Samuel S. C.; Savill, Nicholas J.; Reece, Sarah E.

    2018-01-01

    by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms

  5. 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.

  6. Exercise training normalizes renal blood flow responses to acute hypoxia in experimental heart failure: role of the α1-adrenergic receptor.

    Science.gov (United States)

    Pügge, Carolin; Mediratta, Jai; Marcus, Noah J; Schultz, Harold D; Schiller, Alicia M; Zucker, Irving H

    2016-02-01

    Recent data suggest that exercise training (ExT) is beneficial in chronic heart failure (CHF) because it improves autonomic and peripheral vascular function. In this study, we hypothesized that ExT in the CHF state ameliorates the renal vasoconstrictor responses to hypoxia and that this beneficial effect is mediated by changes in α1-adrenergic receptor activation. CHF was induced in rabbits. Renal blood flow (RBF) and renal vascular conductance (RVC) responses to 6 min of 5% isocapnic hypoxia were assessed in the conscious state in sedentary (SED) and ExT rabbits with CHF with and without α1-adrenergic blockade. α1-adrenergic receptor expression in the kidney cortex was also evaluated. A significant decline in baseline RBF and RVC and an exaggerated renal vasoconstriction during acute hypoxia occurred in CHF-SED rabbits compared with the prepaced state (P renal denervation (DnX) blocked the hypoxia-induced renal vasoconstriction in CHF-SED rabbits. α1-adrenergic protein in the renal cortex of animals with CHF was increased in SED animals and normalized after ExT. These data provide evidence that the acute decline in RBF during hypoxia is caused entirely by the renal nerves but is only partially mediated by α1-adrenergic receptors. Nonetheless, α1-adrenergic receptors play an important role in the beneficial effects of ExT in the kidney. Copyright © 2016 the American Physiological Society.

  7. Assessment of Adaptive Rate Response Provided by Accelerometer, Minute Ventilation and Dual Sensor Compared with Normal Sinus Rhythm During Exercise: A Self-controlled Study in Chronotropically Competent Subjects

    Directory of Open Access Journals (Sweden)

    Yuanyuan Cao

    2015-01-01

    Full Text Available Background: Dual sensor (DS for rate adaption was supposed to be more physiological. To evaluate its superiority, the DS (accelerometer [ACC] and minute ventilation [MV] and normal sinus rate response were compared in a self-controlled way during exercise treadmill testing. Methods: This self-controlled study was performed in atrioventricular block patients with normal sinus function who met the indications of pacemaker implant. Twenty-one patients came to the 1-month follow-up visit. Patients performed a treadmill test 1-month post implant while programmed in DDDR and sensor passive mode. For these patients, sensor response factors were left at default settings (ACC = 8, MV = 3 and sensor indicated rates (SIRs for DS, ACC and MV sensor were retrieved from the pacemaker memories, along with measured sinus node (SN rates from the beginning to 1-minute after the end of the treadmill test, and compared among study groups. Repeated measures analysis of variance and profile analysis, as well as variance analysis of randomized block designs, were used for statistical analysis. Results: Fifteen patients (15/21 were determined to be chronotropically competent. The mean differences between DS SIRs and intrinsic sinus rates during treadmill testing were smaller than those for ACC and MV sensor (mean difference between SIR and SN rate: ACC vs. SN, MV vs. SN, DS vs. SN, respectively, 34.84, 17.60, 16.15 beats/min, though no sensors could mimic sinus rates under the default settings for sensor response factor (ACC vs. SN P-adjusted < 0.001; MV vs. SN P-adjusted = 0.002; DS vs. SN P-adjusted = 0.005. However, both in the range of 1 st minute and first 3 minutes of exercise, only the DS SIR profile did not differ from sinus rates (P-adjusted = 0.09, 0.90, respectively. Conclusions: The DS under default settings provides more physiological rate response during physical activity than the corresponding single sensors (ACC or MV sensor. Further study is needed to

  8. Circadian rhythms in mitochondrial respiration

    NARCIS (Netherlands)

    de Goede, Paul; Wefers, Jakob; Brombacher, Eline Constance; Schrauwen, P; Kalsbeek, A.

    2018-01-01

    Many physiological processes are regulated with a 24h periodicity to anticipate the environmental changes of day to nighttime and vice versa. These 24h regulations, commonly termed circadian rhythms, amongst others control the sleep-wake cycle, locomotor activity and preparation for food

  9. Rhythm Deficits in "Tone Deafness"

    Science.gov (United States)

    Foxton, Jessica M.; Nandy, Rachel K.; Griffiths, Timothy D.

    2006-01-01

    It is commonly observed that "tone deaf" individuals are unable to hear the beat of a tune, yet deficits on simple timing tests have not been found. In this study, we investigated rhythm processing in nine individuals with congenital amusia ("tone deafness") and nine controls. Participants were presented with pairs of 5-note sequences, and were…

  10. Communication of genetic information to families with inherited rhythm disorders.

    Science.gov (United States)

    Burns, Charlotte; James, Cynthia; Ingles, Jodie

    2017-11-23

    Given the dynamic nature of the electrical activity of the heart and ongoing challenges in the diagnostics of inherited heart rhythm disorders, genetic information can be a vital aspect of family management. Communication of genetic information is complex, and the responsibility to convey this information to the family lies with the proband. Current practice falls short, requiring additional support from the clinician and multidisciplinary team. Communication is a 2-part iterative process, reliant on both the understanding of the probands and their ability to effectively communicate with relatives. With the surge of high-throughput genetic testing, results generated are increasingly complex, making the task of communication more challenging. Here we discuss 3 key issues. First, the probabilistic nature of genetic test results means uncertainty is inherent to the practice. Second, secondary findings may arise. Third, personal preferences, values, and family dynamics also come into play and must be acknowledged when considering how best to support effective communication. Here we provide insight into the challenges and provide practical advice for clinicians to support effective family communication. These strategies include acknowledging and managing genetic uncertainty, genetic counseling and informed consent, and consideration of personal and familial barriers to effective communication. We will explore the potential for developing resources to assist clinicians in providing patients with sufficient knowledge and support to communicate complex information to their at-risk relatives. Specialized multidisciplinary clinics remain the best equipped to manage patients and families with inherited heart rhythm disorders given the need for a high level of information and support. Copyright © 2017 Heart Rhythm Society. All rights reserved.

  11. Physiological basis for human autonomic rhythms

    Science.gov (United States)

    Eckberg, D. L.

    2000-01-01

    Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

  12. Chaos control applied to cardiac rhythms represented by ECG signals

    International Nuclear Information System (INIS)

    Borem Ferreira, Bianca; Amorim Savi, Marcelo; Souza de Paula, Aline

    2014-01-01

    The control of irregular or chaotic heartbeats is a key issue in cardiology. In this regard, chaos control techniques represent a good alternative since they suggest treatments different from those traditionally used. This paper deals with the application of the extended time-delayed feedback control method to stabilize pathological chaotic heart rhythms. Electrocardiogram (ECG) signals are employed to represent the cardiovascular behavior. A mathematical model is employed to generate ECG signals using three modified Van der Pol oscillators connected with time delay couplings. This model provides results that qualitatively capture the general behavior of the heart. Controlled ECG signals show the ability of the strategy either to control or to suppress the chaotic heart dynamics generating less-critical behaviors. (paper)

  13. Circadian Rhythms, Sleep, and Disorders of Aging.

    Science.gov (United States)

    Mattis, Joanna; Sehgal, Amita

    2016-04-01

    Sleep-wake cycles are known to be disrupted in people with neurodegenerative disorders. These findings are now supported by data from animal models for some of these disorders, raising the question of whether the disrupted sleep/circadian regulation contributes to the loss of neural function. As circadian rhythms and sleep consolidation also break down with normal aging, changes in these may be part of what makes aging a risk factor for disorders like Alzheimer's disease (AD). Mechanisms underlying the connection between circadian/sleep dysregulation and neurodegeneration remain unclear, but several recent studies provide interesting possibilities. While mechanistic analysis is under way, it is worth considering treatment of circadian/sleep disruption as a means to alleviate symptoms of neurodegenerative disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Timing Matters: Circadian Rhythm in Sepsis, Obstructive Lung Disease, Obstructive Sleep Apnea, and Cancer.

    Science.gov (United States)

    Truong, Kimberly K; Lam, Michael T; Grandner, Michael A; Sassoon, Catherine S; Malhotra, Atul

    2016-07-01

    Physiological and cellular functions operate in a 24-hour cyclical pattern orchestrated by an endogenous process known as the circadian rhythm. Circadian rhythms represent intrinsic oscillations of biological functions that allow for adaptation to cyclic environmental changes. Key clock genes that affect the persistence and periodicity of circadian rhythms include BMAL1/CLOCK, Period 1, Period 2, and Cryptochrome. Remarkable progress has been made in our understanding of circadian rhythms and their role in common medical conditions. A critical review of the literature supports the association between circadian misalignment and adverse health consequences in sepsis, obstructive lung disease, obstructive sleep apnea, and malignancy. Circadian misalignment plays an important role in these disease processes and can affect disease severity, treatment response, and survivorship. Normal inflammatory response to acute infections, airway resistance, upper airway collapsibility, and mitosis regulation follows a robust circadian pattern. Disruption of normal circadian rhythm at the molecular level affects severity of inflammation in sepsis, contributes to inflammatory responses in obstructive lung diseases, affects apnea length in obstructive sleep apnea, and increases risk for cancer. Chronotherapy is an underused practice of delivering therapy at optimal times to maximize efficacy and minimize toxicity. This approach has been shown to be advantageous in asthma and cancer management. In asthma, appropriate timing of medication administration improves treatment effectiveness. Properly timed chemotherapy may reduce treatment toxicities and maximize efficacy. Future research should focus on circadian rhythm disorders, role of circadian rhythm in other diseases, and modalities to restore and prevent circadian disruption.

  15. Human biological rhythm in traditional Chinese medicine

    Directory of Open Access Journals (Sweden)

    Tianxing Zhang

    2016-10-01

    Full Text Available Traditional Chinese medicine (TCM has a comprehensive and thorough understanding of biological rhythm. Biological rhythm is an inherent connotation of “harmony between human and nature”, one of the thoughts in TCM. TCM discusses emphatically circadian rhythm, syzygial rhythm and seasonal rhythm, and particularly circadian and seasonal rhythms. Theories of Yin Yang and Five Elements are the principles and methods, with which TCM understands biological rhythms. Based on theories in TCM, biological rhythm in essence is a continuous variation of the human body state synchronized with natural rhythms, and theories of Yin Yang and Five Elements are both language tools to describe this continuous variation and theoretical tools for its investigation and application. The understandings of biological rhythm in TCM can be applied to etiology, health care, disease control and treatment. Many understandings in TCM have been confirmed by modern research and clinical reports, but there are still some pending issues. TCM is distinguished for its holistic viewpoint on biological rhythms.

  16. Ischemic stroke destabilizes circadian rhythms

    Directory of Open Access Journals (Sweden)

    Borjigin Jimo

    2008-10-01

    Full Text Available Abstract Background The central circadian pacemaker is a remarkably robust regulator of daily rhythmic variations of cardiovascular, endocrine, and neural physiology. Environmental lighting conditions are powerful modulators of circadian rhythms, but regulation of circadian rhythms by disease states is less clear. Here, we examine the effect of ischemic stroke on circadian rhythms in rats using high-resolution pineal microdialysis. Methods Rats were housed in LD 12:12 h conditions and monitored by pineal microdialysis to determine baseline melatonin timing profiles. After demonstration that the circadian expression of melatonin was at steady state, rats were subjected to experimental stroke using two-hour intralumenal filament occlusion of the middle cerebral artery. The animals were returned to their cages, and melatonin monitoring was resumed. The timing of onset, offset, and duration of melatonin secretion were calculated before and after stroke to determine changes in circadian rhythms of melatonin secretion. At the end of the monitoring period, brains were analyzed to determine infarct volume. Results Rats demonstrated immediate shifts in melatonin timing after stroke. We observed a broad range of perturbations in melatonin timing in subsequent days, with rats exhibiting onset/offset patterns which included: advance/advance, advance/delay, delay/advance, and delay/delay. Melatonin rhythms displayed prolonged instability several days after stroke, with a majority of rats showing a day-to-day alternation between advance and delay in melatonin onset and duration. Duration of melatonin secretion changed in response to stroke, and this change was strongly determined by the shift in melatonin onset time. There was no correlation between infarct size and the direction or amplitude of melatonin phase shifting. Conclusion This is the first demonstration that stroke induces immediate changes in the timing of pineal melatonin secretion, indicating

  17. The structurally novel Ca2+ channel blocker Ro 40-5967, which binds to the [3H] desmethoxyverapamil receptor, is devoid of the negative inotropic effects of verapamil in normal and failing rat hearts

    International Nuclear Information System (INIS)

    Clozel, J.P.; Veniant, M.; Osterrieder, W.

    1990-01-01

    Ro 40-5967 is a structurally novel Ca 2+ channel blocker that binds to the verapamil-type receptor of cardiac membranes but that has been shown in isolated guinea-pig hearts to be about ten times less potent a negative inotropic agent than verapamil. The goals of the present study were to confirm these findings in vitro in isolated perfused rat hearts as well as in vivo in conscious rats and to compare Ro 40-5967 to verapamil. The effects of Ro 40-5967 and verapamil were tested not only in normal rats, but also in rats with heart failure induced by chronic myocardial infarction. In isolated Langendorff hearts (without heart failure), no decrease of contractility was observed with Ro 40-5967 up to complete AV block. In contrast, verapamil decreased contractility with an IC50 of 100 nM. In isolated, electrically stimulated rat papillary muscles, the IC50 values for the decrease of contractile force were 15,000 and 440 nM for Ro 40-5967 and verapamil, respectively. In vivo, Ro 40-5967 did not decrease left ventricular contractility (as assessed by changes of dP/dt max +) in rats without and with heart failure. In contrast, verapamil was markedly negative inotropic in both conditions

  18. Archetype, adaptation and the mammalian heart

    NARCIS (Netherlands)

    Meijler, F.L.; Meijler, T.D.

    2011-01-01

    Forty years ago, we started our quest for 'The Holy Grail' of understanding ventricular rate control and rhythm in atrial fibrillation (AF). We therefore studied the morphology and function of a wide range of mammalian hearts. From mouse to whale, we found that all hearts show similar structural

  19. Remission of congenital complete heart block without anti-Ro/La antibodies: A case report

    Directory of Open Access Journals (Sweden)

    Souvik Mitra

    2013-01-01

    Full Text Available Anti-Ro/La negative congenital heart block (CHB is uncommon. We report one such case of CHB, with no associated structural heart disease or maternal autoantibodies. The heart block reverted to sinus rhythm spontaneously at two weeks of age, and the patient remains in sinus rhythm at a one year followup. Whether patients with antibody negative complete heart block have a different clinical course is conjectural.

  20. Clinical predictors of shockable versus non-shockable rhythms in patients with out-of-hospital cardiac arrest

    DEFF Research Database (Denmark)

    Granfeldt, Asger; Wissenberg, Mads; Hansen, Steen Møller

    2016-01-01

    Aim To identify factors associated with a non-shockable rhythm as first recorded heart rhythm. Methods Patients ≥18 years old suffering out-of-hospital cardiac arrest between 2001 and 2012 were identified in the population-based Danish Cardiac Arrest Registry. Danish administrative registries were...... used to identify chronic diseases (within 10 years) and drug prescriptions (within 180 days). A multivariable logistic regression model, including patient related and cardiac arrest related characteristics, was used to estimate odds ratios (OR) for factors associated with non-shockable rhythm. Results...... compared to patients with shockable rhythm. In the adjusted multivariable regression model, pre-existing non-cardiovascular disease and drug prescription were associated with a non-shockable rhythm e.g. chronic obstructive lung disease (OR 1.44 [95% CI: 1.32–1.58]); and the prescription for antidepressants...

  1. Temporal interactions between cortical rhythms

    Directory of Open Access Journals (Sweden)

    Anita K Roopun

    2008-12-01

    Full Text Available Multiple local neuronal circuits support different, discrete frequencies of network rhythm in neocortex. Relationships between different frequencies correspond to mechanisms designed to minimise interference, couple activity via stable phase interactions, and control the amplitude of one frequency relative to the phase of another. These mechanisms are proposed to form a framework for spectral information processing. Individual local circuits can also transform their frequency through changes in intrinsic neuronal properties and interactions with other oscillating microcircuits. Here we discuss a frequency transformation in which activity in two coactive local circuits may combine sequentially to generate a third frequency whose period is the concatenation sum of the original two. With such an interaction, the intrinsic periodicity in each component local circuit is preserved – alternate, single periods of each original rhythm form one period of a new frequency - suggesting a robust mechanism for combining information processed on multiple concurrent spatiotemporal scales.

  2. Don't Miss a Beat: Why Rhythm Is Used in Waldorf Education.

    Science.gov (United States)

    Lopata, Peg

    2000-01-01

    The Waldorf philosophy of education is about awakening and growing an active, inquiring, imaginative mind; a healthy body; and a heart of compassion. This is accomplished by tapping into the natural well of children's rhythmic natures using multisensory approaches. The importance of rhythm in nature, developmental stages, sequencing, and…

  3. Serial binary interval ratios improve rhythm reproduction.

    Science.gov (United States)

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  4. Serial binary interval ratios improve rhythm reproduction

    Directory of Open Access Journals (Sweden)

    Xiang eWu

    2013-08-01

    Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  5. Electrocardiogram as an important tool in Preventive & Community Medicine - A rare case report of asymptomatic non paroxysmal accelerated junctional rhythm detected on routine ECG

    Directory of Open Access Journals (Sweden)

    Raghavendra Deolalikar

    2015-03-01

    Full Text Available Fifty four year old asymptomatic employee was detected to have Inverted P waves with normal QRS complex on Electrocardiogram [ECG] during his Annual Medical Examination. The ECG reverted to normal after few days. Inverted P is suggestive of retrograde conduct of impulse from A-V Node. Case of Non Paroxysmal Accelerated Junctional Rhythm. Causes are inferior wall myocardial infarction, myocarditis or recent open heart surgery. Troponin T Test was negative, Treadmill test was negative, and 2D Echo showed 55 % ejection fraction with no regional wall motion abnormalities. It needs no treatment if underlying causes are ruled out. Case would have gone un-noticed as patient was asymptomatic, thus emphasizing the importance of ECG in preventive and community medicine.

  6. Mitochondrial apoptotic pathway activation in the atria of heart failure patients due to mitral and tricuspid regurgitation.

    Science.gov (United States)

    Chang, Jen-Ping; Chen, Mien-Cheng; Liu, Wen-Hao; Lin, Yu-Sheng; Huang, Yao-Kuang; Pan, Kuo-Li; Ho, Wan-Chun; Fang, Chih-Yuan; Chen, Chien-Jen; Chen, Huang-Chung

    2015-08-01

    Apoptosis occurs in atrial cardiomyocytes in mitral and tricuspid valve disease. The purpose of this study was to examine the respective roles of the mitochondrial and tumor necrosis factor-α receptor associated death domain (TRADD)-mediated death receptor pathways for apoptosis in the atrial cardiomyocytes of heart failure patients due to severe mitral and moderate-to-severe tricuspid regurgitation. This study comprised eighteen patients (7 patients with persistent atrial fibrillation and 11 in sinus rhythm). Atrial appendage tissues were obtained during surgery. Three purchased normal human left atrial tissues served as normal controls. Moderately-to-severely myolytic cardiomyocytes comprised 59.7±22.1% of the cardiomyocytes in the right atria and 52.4±12.9% of the cardiomyocytes in the left atria of mitral and tricuspid regurgitation patients with atrial fibrillation group and comprised 58.4±24.8% of the cardiomyocytes in the right atria of mitral and tricuspid regurgitation patients with sinus rhythm. In contrast, no myolysis was observed in the normal human adult left atrial tissue samples. Immunohistochemical analysis showed expression of cleaved caspase-9, an effector of the mitochondrial pathways, in the majority of right atrial cardiomyocytes (87.3±10.0%) of mitral and tricuspid regurgitation patients with sinus rhythm, and right atrial cardiomyocytes (90.6±31.4%) and left atrial cardiomyocytes (70.7±22.0%) of mitral and tricuspid regurgitation patients with atrial fibrillation. In contrast, only 5.7% of cardiomyocytes of the normal left atrial tissues showed strongly positive expression of cleaved caspase-9. Of note, none of the atrial cardiomyocytes in right atrial tissue in sinus rhythm and in the fibrillating right and left atria of mitral and tricuspid regurgitation patients, and in the normal human adult left atrial tissue samples showed cleaved caspase-8 expression, which is a downstream effector of TRADD of the death receptor pathway

  7. Heart Health - Brave Heart

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Brave Heart Past Issues / Winter 2009 Table of Contents For ... you can have a good life after a heart attack." Lifestyle Changes Surviving—and thriving—after such ...

  8. Heart Valve Diseases

    Science.gov (United States)

    Your heart has four valves. Normally, these valves open to let blood flow through or out of your heart, and then shut to keep it from flowing ... close tightly. It's one of the most common heart valve conditions. Sometimes it causes regurgitation. Stenosis - when ...

  9. Acquisition of speech rhythm in first language.

    Science.gov (United States)

    Polyanskaya, Leona; Ordin, Mikhail

    2015-09-01

    Analysis of English rhythm in speech produced by children and adults revealed that speech rhythm becomes increasingly more stress-timed as language acquisition progresses. Children reach the adult-like target by 11 to 12 years. The employed speech elicitation paradigm ensured that the sentences produced by adults and children at different ages were comparable in terms of lexical content, segmental composition, and phonotactic complexity. Detected differences between child and adult rhythm and between rhythm in child speech at various ages cannot be attributed to acquisition of phonotactic language features or vocabulary, and indicate the development of language-specific phonetic timing in the course of acquisition.

  10. Effect of (+)-amphetamine on the retention of 3H-catecholamines in slices of normal and reserpinized rat brain and heart

    International Nuclear Information System (INIS)

    Ross, S.B.; Renyi, A.L.

    1978-01-01

    The effect of reserpine on the inhibition by (+)-amphetamine and cocaine of the accumulation of 3 H-dopamine (DA) in striatal slices and 3 H-noradrenaline (NA) in slices of cerebral occipital cortex and heart atrium of rats and the release of the 3 H-amines from these tissues were examined. Reserpine (5 mg/kg intraperitoneally) was injected 18 hours before the experiments. It was found that reserpine markedly enhanced the in vitro potency of amphetamine in the striatum and heart but only slightly in the cortex. After administration in vivo (+)-amphetamine was about 10 times more potent in reducing the amine accumulation in the cortex as in the striatum. Reserpine enhanced the effect in both regions. The inhibitory potency of cocaine in vitro was unchanged by reserpine in the striatum but was reduced in the cortex and heart. Reserpine did not change the inhibitory potency of desipramine in the cortex and heart. The release of the 3 H-amines by (+)-amphetamine was enhanced by reserpine in the striatum and heart but the small release produced in the cortex was not increased. The release produced by cocaine was similarly enhanced by reserpine but cocaine was much less active than (+)-amphetamine. The results indicate that (+)-amphetamine and cocaine inhibit the amine accumulation by different mechanisms. (author)

  11. Circadian rhythms in healthy aging--effects downstream from the pacemaker

    Science.gov (United States)

    Monk, T. H.; Kupfer, D. J.

    2000-01-01

    Using both previously published findings and entirely new data, we present evidence in support of the argument that the circadian dysfunction of advancing age in the healthy human is primarily one of failing to transduce the circadian signal from the circadian timing system (CTS) to rhythms "downstream" from the pacemaker rather than one of failing to generate the circadian signal itself. Two downstream rhythms are considered: subjective alertness and objective performance. For subjective alertness, we show that in both normal nychthemeral (24 h routine, sleeping at night) and unmasking (36 h of constant wakeful bed rest) conditions, advancing age, especially in men, leads to flattening of subjective alertness rhythms, even when circadian temperature rhythms are relatively robust. For objective performance, an unmasking experiment involving manual dexterity, visual search, and visual vigilance tasks was used to demonstrate that the relationship between temperature and performance is strong in the young, but not in older subjects (and especially not in older men).

  12. Nuclear cardiology and heart failure

    International Nuclear Information System (INIS)

    Giubbini, Raffaele; Bertagna, Francesco; Milan, Elisa; Mut, Fernando; Dondi, Maurizio; Metra, Marco; Rodella, Carlo

    2009-01-01

    The prevalence of heart failure in the adult population is increasing. It varies between 1% and 2%, although it mainly affects elderly people (6-10% of people over the age of 65 years will develop heart failure). The syndrome of heart failure arises as a consequence of an abnormality in cardiac structure, function, rhythm, or conduction. Coronary artery disease is the leading cause of heart failure and it accounts for this disorder in 60-70% of all patients affected. Nuclear techniques provide unique information on left ventricular function and perfusion by gated-single photon emission tomography (SPECT). Myocardial viability can be assessed by both SPECT and PET imaging. Finally, autonomic dysfunction has been shown to increase the risk of death in patients with heart disease and this may be applicable to all patients with cardiac disease regardless of aetiology. MIBG scanning has a very promising prognostic value in patients with heart failure. (orig.)

  13. Nuclear cardiology and heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Giubbini, Raffaele; Bertagna, Francesco [University of Brescia, Department of Nuclear Medicine, Brescia (Italy); Milan, Elisa [Ospedale Di Castelfranco Veneto, Nuclear Medicine Unit, Castelfranco Veneto (Italy); Mut, Fernando; Dondi, Maurizio [International Atomic Energy Agency, Nuclear Medicine Section, Division of Human Health, Vienna (Austria); Metra, Marco [University of Brescia, Department of Cardiology, Brescia (Italy); Rodella, Carlo [Health Physics Department, Spedali Civili di Brescia, Brescia (Italy)

    2009-12-15

    The prevalence of heart failure in the adult population is increasing. It varies between 1% and 2%, although it mainly affects elderly people (6-10% of people over the age of 65 years will develop heart failure). The syndrome of heart failure arises as a consequence of an abnormality in cardiac structure, function, rhythm, or conduction. Coronary artery disease is the leading cause of heart failure and it accounts for this disorder in 60-70% of all patients affected. Nuclear techniques provide unique information on left ventricular function and perfusion by gated-single photon emission tomography (SPECT). Myocardial viability can be assessed by both SPECT and PET imaging. Finally, autonomic dysfunction has been shown to increase the risk of death in patients with heart disease and this may be applicable to all patients with cardiac disease regardless of aetiology. MIBG scanning has a very promising prognostic value in patients with heart failure. (orig.)

  14. Analysis of Handwriting based on Rhythm Perception

    Science.gov (United States)

    Saito, Kazuya; Uchida, Masafumi; Nozawa, Akio

    Humanity fluctuation was reported in some fields. In handwriting process, fluctuation appears on handwriting-velocity. In this report, we focused attention on human rhythm perception and analyzed fluctuation in handwriting process. As a result, 1/f noise related to rhythm perception and features may caused by Kahneman's capacity model were measured on handwriting process.

  15. Development of cortisol circadian rhythm in infancy.

    NARCIS (Netherlands)

    Weerth, C. de; Zijl, R.H.

    2003-01-01

    BACKGROUND AND AIMS: Cortisol is the final product of the hypothalamus-pituitary-adrenal (HPA) axis. It is secreted in a pulsatile fashion that displays a circadian rhythm. Infants are born without a circadian rhythm in cortisol and they acquire it during their first year of life. Studies do not

  16. Heart MRI

    Science.gov (United States)

    Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI

  17. Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. E.; Gohel, Bakul; Kim, K.; Kwon, H.; An, Kyung Min [Center for Biosignals, Korea Research Institute of Standards and Science(KRISS), Daejeon (Korea, Republic of)

    2015-12-15

    Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8–13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

  18. Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

    International Nuclear Information System (INIS)

    Kim, J. E.; Gohel, Bakul; Kim, K.; Kwon, H.; An, Kyung Min

    2015-01-01

    Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8–13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively

  19. Is Heart Period Variability Associated with the Administration of Lifesaving Interventions in Individual Prehospital Trauma Patients with Normal Standard Vital Signs?

    Science.gov (United States)

    2010-08-01

    heart period variability as an indicator of mortality in intensive care unit patients many hours before death. Similarly, re- cent studies using data...the Department of Health and Kinesiology (CAR), The University of Texas at San Antonio, San An- tonio, TX; U.S. Army Institute of Surgical Research (CAR

  20. The Risk of Heart Failure and Cardiometabolic Complications in Obesity May Be Masked by an Apparent Healthy Status of Normal Blood Glucose

    Directory of Open Access Journals (Sweden)

    Shuchita Tiwari

    2013-01-01

    Full Text Available Although many obese individuals are normoglycemic and asymptomatic of cardiometabolic complications, this apparent healthy state may be a misnomer. Since heart failure is a major cause of mortality in obesity, we investigated the effects of heme-oxygenase (HO on heart failure and cardiometabolic complications in obese normoglycemic Zucker-fatty rats (ZFs. Treatment with the HO-inducer, hemin, reduced markers of heart failure, such as osteopontin and osteoprotegerin, abated left-ventricular (LV hypertrophy/fibrosis, extracellular matrix/profibrotic proteins including collagen IV, fibronectin, TGF-β1, and reduced cardiac lesions. Furthermore, hemin suppressed inflammation by abating macrophage chemoattractant protein-1, macrophage-inflammatory protein-1 alpha, TNF-α, IL-6, and IL-1β but enhanced adiponectin, atrial-natriuretic peptide (ANP, HO activity, insulin sensitivity, and glucose metabolism. Correspondingly, hemin improved several hemodynamic/echocardiographic parameters including LV-diastolic wall thickness, LV-systolic wall thickness, mean-arterial pressure, arterial-systolic pressure, arterial-diastolic pressure, LV-developed pressure, +dP/dt, and cardiac output. Contrarily, the HO-inhibitor, stannous mesoporphyrin nullified the hemin effect, exacerbating inflammatory/oxidative insults and aggravated insulin resistance (HOMA-index. We conclude that perturbations in insulin signaling and cardiac function may be forerunners to overt hyperglycemia and heart failure in obesity. Importantly, hemin improves cardiac function by suppressing markers of heart failure, LV hypertrophy, cardiac lesions, extracellular matrix/profibrotic proteins, and inflammatory/oxidative mediators, while concomitantly enhancing the HO-adiponectin-ANP axis.

  1. Dynamic markers of altered gait rhythm in amyotrophic lateral sclerosis

    Science.gov (United States)

    Hausdorff, J. M.; Lertratanakul, A.; Cudkowicz, M. E.; Peterson, A. L.; Kaliton, D.; Goldberger, A. L.

    2000-01-01

    Amyotrophic lateral sclerosis (ALS) is a disorder marked by loss of motoneurons. We hypothesized that subjects with ALS would have an altered gait rhythm, with an increase in both the magnitude of the stride-to-stride fluctuations and perturbations in the fluctuation dynamics. To test for this locomotor instability, we quantitatively compared the gait rhythm of subjects with ALS with that of normal controls and with that of subjects with Parkinson's disease (PD) and Huntington's disease (HD), pathologies of the basal ganglia. Subjects walked for 5 min at their usual pace wearing an ankle-worn recorder that enabled determination of the duration of each stride and of stride-to-stride fluctuations. We found that the gait of patients with ALS is less steady and more temporally disorganized compared with that of healthy controls. In addition, advanced ALS, HD, and PD were associated with certain common, as well as apparently distinct, features of altered stride dynamics. Thus stride-to-stride control of gait rhythm is apparently compromised with ALS. Moreover, a matrix of markers based on gait dynamics may be useful in characterizing certain pathologies of motor control and, possibly, in quantitatively monitoring disease progression and evaluating therapeutic interventions.

  2. Sleep and circadian rhythm disturbance in bipolar disorder.

    Science.gov (United States)

    Bradley, A J; Webb-Mitchell, R; Hazu, A; Slater, N; Middleton, B; Gallagher, P; McAllister-Williams, H; Anderson, K N

    2017-07-01

    Subjective reports of insomnia and hypersomnia are common in bipolar disorder (BD). It is unclear to what extent these relate to underlying circadian rhythm disturbance (CRD). In this study we aimed to objectively assess sleep and circadian rhythm in a cohort of patients with BD compared to matched controls. Forty-six patients with BD and 42 controls had comprehensive sleep/circadian rhythm assessment with respiratory sleep studies, prolonged accelerometry over 3 weeks, sleep questionnaires and diaries, melatonin levels, alongside mood, psychosocial functioning and quality of life (QoL) questionnaires. Twenty-three (50%) patients with BD had abnormal sleep, of whom 12 (52%) had CRD and 29% had obstructive sleep apnoea. Patients with abnormal sleep had lower 24-h melatonin secretion compared to controls and patients with normal sleep. Abnormal sleep/CRD in BD was associated with impaired functioning and worse QoL. BD is associated with high rates of abnormal sleep and CRD. The association between these disorders, mood and functioning, and the direction of causality, warrants further investigation.

  3. A New Perspective for Parkinson's Disease: Circadian Rhythm.

    Science.gov (United States)

    Li, Siyue; Wang, Yali; Wang, Fen; Hu, Li-Fang; Liu, Chun-Feng

    2017-02-01

    Circadian rhythm is manifested by the behavioral and physiological changes from day to night, which is controlled by the pacemaker and its regulator. The former is located at the suprachiasmatic nuclei (SCN) in the anterior hypothalamus, while the latter is composed of clock genes present in all tissues. Circadian desynchronization influences normal patterns of day-night rhythms such as sleep and alertness cycles, rest and activity cycles. Parkinson's disease (PD) exhibits diurnal fluctuations. Circadian dysfunction has been observed in PD patients and animal models, which may result in negative consequences to the homeostasis and even exacerbate the disease progression. Therefore, circadian therapies, including light stimulation, physical activity, dietary and social schedules, may be helpful for PD patients. However, the cellular and molecular mechanisms that underlie the circadian dysfunction in PD remain elusive. Further research on circadian patterns is needed. This article summarizes the existing research on the circadian rhythms in PD, focusing on the clinical symptom variations, molecular changes, as well as the available treatment options.

  4. Pediatric cardiology. Clinical and practical experiences with heart diseases of children, juveniles and young adults

    International Nuclear Information System (INIS)

    Haas, Nikolaus A.

    2011-01-01

    The book on pediatric cardiology covers the following chapters: (I) Fundamentals and diagnostics: pediatric cardiologic anamnesis, electrocardiograms, thorax X-radiography, MRT and CT of the heart, nuclear medical diagnostics, exercise tests, heart catheter examination, electrophysiological tests. (II) Leading symptoms: Cyanosis, cardiac murmur, thorax pain, palpitation, syncopes. (III) Disease pictures: congenital heart defects, acquired heart defects, cardiomyopathies, heart rhythm disturbances, heart insufficiency, arterial hypertension, pulmonary hypertension, other heart involving syndromes. (IV) Therapy: Catheter interventional therapy, post-surgical pediatric cardiac therapy, surgery involving the life-support machine, mechanical cardiovascular support systems, initial treatment of newborns with critical heart defects, heart transplantation, vaccination of children with heart diseases, medicinal therapy.

  5. Shared Components of Rhythm Generation for Locomotion and Scratching Exist Prior to Motoneurons

    Directory of Open Access Journals (Sweden)

    Zhao-Zhe Hao

    2017-08-01

    Full Text Available Does the spinal cord use a single network to generate locomotor and scratching rhythms or two separate networks? Previous research showed that simultaneous swim and scratch stimulation (“dual stimulation” in immobilized, spinal turtles evokes a single rhythm in hindlimb motor nerves with a frequency often greater than during swim stimulation alone or scratch stimulation alone. This suggests that the signals that trigger swimming and scratching converge and are integrated within the spinal cord. However, these results could not determine whether the integration occurs in motoneurons themselves or earlier, in spinal interneurons. Here, we recorded intracellularly from hindlimb motoneurons during dual stimulation. Motoneuron membrane potentials displayed regular oscillations at a higher frequency during dual stimulation than during swim or scratch stimulation alone. In contrast, arithmetic addition of the oscillations during swimming alone and scratching alone with various delays always generated irregular oscillations. Also, the standard deviation of the phase-normalized membrane potential during dual stimulation was similar to those during swimming or scratching alone. In contrast, the standard deviation was greater when pooling cycles of swimming alone and scratching alone for two of the three forms of scratching. This shows that dual stimulation generates a single rhythm prior to motoneurons. Thus, either swimming and scratching largely share a rhythm generator or the two rhythms are integrated into one rhythm by strong interactions among interneurons.

  6. Brugada syndrome: report of the second consensus conference: endorsed by the Heart Rhythm Society and the European Heart Rhythm Association

    NARCIS (Netherlands)

    Antzelevitch, Charles; Brugada, Pedro; Borggrefe, Martin; Brugada, Josep; Brugada, Ramon; Corrado, Domenico; Gussak, Ihor; LeMarec, Herve; Nademanee, Koonlawee; Perez Riera, Andres Ricardo; Shimizu, Wataru; Schulze-Bahr, Eric; Tan, Hanno; Wilde, Arthur

    2005-01-01

    Since its introduction as a clinical entity in 1992, the Brugada syndrome has progressed from being a rare disease to one that is second only to automobile accidents as a cause of death among young adults in some countries. Electrocardiographically characterized by a distinct ST-segment elevation in

  7. Heart rate variability in patients with mitral stenosis: A study of 20 cases from King Abdulaziz Univ. Hospital

    International Nuclear Information System (INIS)

    Al-Hazimi, A.; Al-Ama, N.; Marouf, M.

    2002-01-01

    Left atrial enlargement in mitral stenosis predisposes to atrial fibrillation (AF). Analysis of heart rate variability (HRV) prior to the onset of an arrhythmia may show alterations in autonomic balance that are known to predispose to the development of AF. The aim of this study was to determine whether HRV in patients with rheumatic mitral stenosis (MS) is abnormal in comparison to normal controls, and to find the relationship between the left atrial size and HRV in patients with MS in sinus rhythm in AF. A series of 24-hour ambulatory Holter electrocardiogram recordings were obtained for 10 consecutive, newly diagnosed untreated subjects with pure mitral stenosis in sinus rhythm, 10 with mitral stenosis complicated by atrial fibrillation and 10 age-matched normal controls. Digitized records were processed using time domain and power spectral analysis. In patients with mitral stenosis in sinus rhythm, we observed significant decrease of the standard deviation of RR intervals (SDRR), as well as of the root mean square of successive RR interval differences (RMSSD) and Edinburgh index (sNN50), while in patients with AF, the RMSSD and sNN50 were much larger than those in normal. The areas under all spectral bands were markedly increased in patients with AF compared with normal. HRV measures were independent of atrial size in both groups. Decreased HRV in mitral stenosis patients with sinus rhythm suggests increased sympathetic activity in patients prone to atrial fibrillation, while marked increased of HRV in patients with AF may indicate that parasympathetic activity modulates the intrinsic behavior of the atrioventricular node during atrial fibrillation. The evaluation of HRV may be a useful tool for the identification of patients predisposed to AF. (author)

  8. Heart murmurs

    Science.gov (United States)

    Chest sounds - murmurs; Heart sounds - abnormal; Murmur - innocent; Innocent murmur; Systolic heart murmur; Diastolic heart murmur ... The heart has 4 chambers: Two upper chambers (atria) Two lower chambers (ventricles) The heart has valves that close ...

  9. The effects of gender on circadian rhythm of human physiological indexes in high temperature environment

    Science.gov (United States)

    Zheng, G. Z.; Li, K.; Bu, W. T.; Lu, Y. Z.; Wang, Y. J.

    2018-03-01

    In the context of frequent high temperature weather in recent years, peoples’ physical health is seriously threatened by the indoor high temperature. The physiological activities of human body show a certain changes of circadian rhythm. In this paper, the circadian rhythms of the physiological indexes in indoor high temperature environment were quantified and compared between the male subjects and female subjects. Ten subjects (five males and five females) were selected. The temperature conditions were set at 28°C, 32°C, 36°C and 38°C, respectively. The blood pressure, heart rate, rectal temperature, eardrum temperature, forehead temperature and mean skin temperature were measured for 24 hours continuously. The medians, amplitudes and acrophases of the circadian rhythms were obtained by the cosinor analysis method. Then the effects of gender on the circadian rhythm of the human body in high temperature environment were analyzed. The results indicate that, compared with the female subjects, the male medians of the systolic pressure and diastolic pressure were higher, and the male medians of heart rate and rectal temperature were lower, however, no significant differences were found between eardrum temperature, forehead temperature and mean skin temperature. This study can provide scientific basis for the health protection of the indoor relevant personnel.

  10. Fluctuation of biological rhythm in finger tapping

    Science.gov (United States)

    Yoshinaga, H.; Miyazima, S.; Mitake, S.

    2000-06-01

    By analyzing biological rhythms obtained from finger tapping, we have investigated the differences of two biological rhythms between healthy and handicapped persons caused by Parkinson, brain infraction, car accident and so on. In this study, we have observed the motion of handedness of all subjects and obtained a slope a which characterizes a power-law relation between frequency and amplitude of finger-tapping rhythm. From our results, we have estimated that the slope a=0.06 is a rough criterion in order to distinguish healthy and handicapped persons.

  11. [Autism spectrum disorders and mu rhythm. A new neurophysiological view].

    Science.gov (United States)

    Palau-Baduell, Montserrat; Valls-Santasusana, Antonio; Salvadó-Salvadó, Berta

    2011-03-01

    Electroencephalographic studies of subjects with autism spectrum disorders (ASD) provide evidences of brain functional aspects in this pathology. Mu rhythm can be reactive in normal population (mu suppression) to both self-movements and to movements performed by others. These reactivities are considered to be related to mirror neurons activity. Subjects with ASD show significant mu suppression to self-movements but they fail to react to the movements performed by others. These findings support the hypothesis of a dysfunctional mirror neurons system in individuals with ASD. Moreover, dysfunction of mirror neurons would be related to social and communicative impairments, cognitive deficits and impairment imitation skills associated with ASD.

  12. Cardiopulmonary Exercise Testing in Fontan Patients With and Without Isomerism (Heterotaxy) as Compared to Patients With Primary Ciliary Dyskinesia and Subjects With Structurally Normal Hearts

    DEFF Research Database (Denmark)

    Loomba, Rohit S; Danduran, Michael; Nielsen, Kim G

    2017-01-01

    with and without isomerism. We have now compared these finding with those from patients with primary ciliary dyskinesia, as many patients with isomerism have ciliary dyskinesia. We identified patients having the Fontan circulation with and without isomerism who had undergone cardiopulmonary exercise testing......, comparing the findings from healthy individuals undergoing exercise, and a comparable number of individuals with primary ciliary dyskinesia but no congenital heart disease. We were able to include a total of 68 patients in our study, with 17 in each of the four groups. Cardiopulmonary exercise testing...

  13. Rhythm disturbances in childhood obstructive sleep apnea during apnea-hypopnea episodes

    International Nuclear Information System (INIS)

    Khositseth, Anant; Chokechuleekorn, Jittamas; Kuptanon, Teeradej; Leejakpai, Anchalee

    2013-01-01

    Obstructive sleep apnoea (OSA) can result in cardiovascular complications. Nocturnal arrhythmias are reported up to 50% of adult OSA patients. Arrhythmias and heart rate variability in children with OSA have not been well studied. We sought to study rhythm disturbances in childhood OSA and also to analyze the relationship of heart rate variability to the severity of OSA in children. In a retrospective cross sectional study, records of children aged < 15 years with history of snoring and suspected OSA, who had undergone polysomnography (PSG) for first time were analyzed. The cardiac rhythm and heart rate variability were studied during PSG. A total of 124 patients diagnosed with OSA were grouped into mild (n = 52), moderate (n = 30), and severe (n = 42) OSA. During PSG, all had sinus arrhythmias and only three patients had premature atrial contractions (PACs). The standard deviation of heart rate (SD-HR) during rapid eye movement (REM) sleep in severe OSA (9.1 ± 2.4) was significantly higher than SD-HR in mild OSA (7.5 ± 1.3, P < 0.0001). The maximum heart rate (max-HR) during REM-sleep in severe OSA (132.1 ± 22.1) was significantly higher than the max-HR in mild OSA (121.3 ± 12.6 bpm, P = 0.016). There was no significant arrhythmia in children with OSA during their sleep. Heart rate variability correlated with the severity of OSA

  14. Abnormality of circadian rhythm of serum melatonin and other biochemical parameters in fibromyalgia syndrome.

    Science.gov (United States)

    Mahdi, Abbas Ali; Fatima, Ghizal; Das, Siddhartha Kumar; Verma, Nar Singh

    2011-04-01

    Fibromyalgia syndrome (FMS) is a complex chronic condition causing widespread pain and variety of other symptoms. It produces pain in the soft tissues located around joints throughout the body. FMS has unknown etiology and its pathophysiology is not fully understood. However, abnormality in circadian rhythm of hormonal profiles and cytokines has been observed in this disorder. Moreover, there are reports of deficiency of serotonin, melatonin, cortisol and cytokines in FMS patients, which are fully regulated by circadian rhythm. Melatonin, the primary hormone of the pineal gland regulates the body's circadian rhythm and normally its levels begin to rise in the mid-to-late evening, remain high for most of the night, and then decrease in the early morning. FMS patients have lower melatonin secretion during the hours of darkness than the healthy subjects. This may contribute to impaired sleep at night, fatigue during the day and changed pain perception. Studies have shown blunting of normal diurnal cortisol rhythm, with elevated evening serum cortisol level in patients with FMS. Thus, due to perturbed level of cortisol secretion several symptoms of FMS may occur. Moreover, disturbed cytokine levels have also been reported in FMS patients. Therefore, circadian rhythm can be an important factor in the pathophysiology, diagnosis and treatment of FMS. This article explores the circadian pattern of abnormalities in FMS patients, as this may help in better understanding the role of variation in symptoms of FMS and its possible relationship with circadian variations of melatonin, cortisol, cytokines and serotonin levels.

  15. Variability of left ventricular ejection fraction and volumes with quantitative gated SPECT: influence of algorithm, pixel size and reconstruction parameters in small and normal-sized hearts

    International Nuclear Information System (INIS)

    Hambye, Anne-Sophie; Vervaet, Ann; Dobbeleir, Andre

    2004-01-01

    Several software packages are commercially available for quantification of left ventricular ejection fraction (LVEF) and volumes from myocardial gated single-photon emission computed tomography (SPECT), all of which display a high reproducibility. However, their accuracy has been questioned in patients with a small heart. This study aimed to evaluate the performances of different software and the influence of modifications in acquisition or reconstruction parameters on LVEF and volume measurements, depending on the heart size. In 31 patients referred for gated SPECT, 64 2 and 128 2 matrix acquisitions were consecutively obtained. After reconstruction by filtered back-projection (Butterworth, 0.4, 0.5 or 0.6 cycles/cm cut-off, order 6), LVEF and volumes were computed with different software [three versions of Quantitative Gated SPECT (QGS), the Emory Cardiac Toolbox (ECT) and the Stanford University (SU-Segami) Medical School algorithm] and processing workstations. Depending upon their end-systolic volume (ESV), patients were classified into two groups: group I (ESV>30 ml, n=14) and group II (ESV 2 to 128 2 were associated with significantly larger volumes as well as lower LVEF values. Increasing the filter cut-off frequency had the same effect. With SU-Segami, a larger matrix was associated with larger end-diastolic volumes and smaller ESVs, resulting in a highly significant increase in LVEF. Increasing the filter sharpness, on the other hand, had no influence on LVEF though the measured volumes were significantly larger. (orig.)

  16. Dysrhythmia: a specific congenital rhythm perception deficit

    Directory of Open Access Journals (Sweden)

    Jacques eLaunay

    2014-02-01

    Full Text Available Why do some people have problems ‘feeling the beat’? Here we investigate participants with congenital impairments in musical rhythm perception and production. A web-based version of the Montreal Battery of Evaluation of Amusia (MBEA was used to screen for difficulties with rhythmic processing in a large sample and we identified three ‘dysrhythmic’ individuals who scored below cut-off for the rhythm subtest, but not the pitch-based subtests. Follow-up testing in the laboratory was conducted to characterize the nature of both rhythm perception and production deficits in these dysrhythmic individuals. We found that they differed from control participants when required to synchronize their tapping to an external stimulus with a metrical pulse, but not when required to tap spontaneously (with no external stimulus or to tap in time to an isochronous stimulus. Dysrhythmics exhibited a general tendency to tap at half the expected tempo when asked to synchronize to the beat of strongly metrical rhythms. These results suggest that the individuals studied here did not have motor production problems, but suffer from a selective rhythm perception deficit that influences the ability to entrain to metrical rhythms.

  17. Spontaneous group synchronization of movements and respiratory rhythms.

    Directory of Open Access Journals (Sweden)

    Erwan Codrons

    Full Text Available We tested whether pre-assigned arm movements performed in a group setting spontaneously synchronized and whether synchronization extended to heart and respiratory rhythms. We monitored arm movements, respiration and electrocardiogram at rest and during spontaneous, music and metronome-associated arm-swinging. No directions were given on whether or how the arm swinging were to be synchronized between participants or with the external cues. Synchronization within 3 groups of 10 participants studied collectively was compared with pseudo-synchronization of 3 groups of 10 participants that underwent an identical protocol but in an individual setting. Motor synchronization was found to be higher in the collective groups than in the individuals for the metronome-associated condition. On a repetition of the protocol on the following day, motor synchronization in the collective groups extended to the spontaneous, un-cued condition. Breathing was also more synchronized in the collective groups than in the individuals, particularly at rest and in the music-associated condition. Group synchronization occurs without explicit instructions, and involves both movements and respiratory control rhythms.

  18. Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure

    Directory of Open Access Journals (Sweden)

    Maria Angeles Bonmati-Carrion

    2014-12-01

    Full Text Available Currently, in developed countries, nights are excessively illuminated (light at night, whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD, including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption. This review addresses the state of the art regarding the crosstalk between light and the circadian system.

  19. A cross-cultural study of the rhythm in English and Japanese popular music

    NARCIS (Netherlands)

    Sadakata, M.; Desain, P.W.M.; Honing, H.J.; Patel, A.D.; Iversen, J.R.

    2004-01-01

    The aim of this study is to investigate the linguistic impact on rhythm in music. It has been shown that the composer’s native language exerts an influence on the music composed [10] using the normalized Pairwise Variability Index [5]. Our project aims at finding more evidence for the linguistic

  20. Nonlinear Changes in the Rhythm of European Art Music: Quantitative Support for Historical Musicology

    DEFF Research Database (Denmark)

    Hansen, Niels Christian; Sadakata, Makiko; Pearce, Marcus

    2016-01-01

    Research has used the normalized pairwise variability index (nPVI) to examine relationships between musical rhythm and durational contrast in composers’ native languages. Applying this methodology, linearly increasing nPVI in Austro-German, but not Italian music has recently been ascribed to waning...

  1. Nonlinear changes in the rhythm of European art music: Quantitative support for historical musicology

    NARCIS (Netherlands)

    Hansen, N.C.; Sadakata, M.; Pearce, M.

    2016-01-01

    Research has used the normalized pairwise variability index (nPVI) to examine relationships between musical rhythm and durational contrast in composers’ native languages. Applying this methodology, linearly increasing nPVI in Austro-German, but not Italian music has recently been ascribed to waning

  2. Nonlinear Changes in the Rhythm of European Art Music: Quantitative Support for Historical Musicology

    NARCIS (Netherlands)

    Hansen, N.C.; Sadakata, M.; Pearce, M.

    2016-01-01

    Research has used the normalized pairwise variability index (nPVI) to examine relationships between musical rhythm and durational contrast in composers’ native languages. Applying this methodology, linearly increasing nPVI in Austro-German, but not Italian music has recently been ascribed to waning

  3. The role of feeding rhythm, adrenal hormones and neuronal inputs in synchronizing daily clock gene rhythms in the liver.

    Science.gov (United States)

    Su, Yan; Cailotto, Cathy; Foppen, Ewout; Jansen, Remi; Zhang, Zhi; Buijs, Ruud; Fliers, Eric; Kalsbeek, Andries

    2016-02-15

    The master clock in the hypothalamic suprachiasmatic nucleus (SCN) is assumed to distribute rhythmic information to the periphery via neural, humoral and/or behavioral connections. Until now, feeding, corticosterone and neural inputs are considered important signals for synchronizing daily rhythms in the liver. In this study, we investigated the necessity of neural inputs as well as of the feeding and adrenal hormone rhythms for maintaining daily hepatic clock gene rhythms. Clock genes kept their daily rhythm when only one of these three signals was disrupted, or when we disrupted hepatic neuronal inputs together with the adrenal hormone rhythm or with the daily feeding rhythm. However, all clock genes studied lost their daily expression rhythm after simultaneous disruption of the feeding and adrenal hormone rhythm. These data indicate that either a daily rhythm of feeding or adrenal hormones should be present to synchronize clock gene rhythms in the liver with the SCN. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Cataracts, radiculomegaly, septal heart defects and hearing loss in two unrelated adult females with normal intelligence and similar facial appearance : Confirmation of a syndrome

    NARCIS (Netherlands)

    Aalfs, CM; Oosterwijk, JC; VanSchooneveld, MJ; Begeman, CJ; Wabeke, KB; Hennekam, RCM

    Two unrelated, adult females with normal intelligence are described. They show a similar clinical picture with a long and narrow face, congenital cataract, microphthalmia, microcornea, a high nasal bridge, a short nose, a broad nasal tip, a long philtrum, bilateral hearing loss, persistent primary

  5. Amino acid transamination is crucial for ischaemic cardioprotection in normal and preconditioned isolated rat hearts--focus on L-glutamate

    DEFF Research Database (Denmark)

    Løfgren, Bo; Povlsen, Jonas Agerlund; Rasmussen, Lars Ege

    2010-01-01

    We have found that cardioprotection by l-glutamate mimics protection by classical ischaemic preconditioning (IPC). We investigated whether the effect of IPC involves amino acid transamination and whether IPC modulates myocardial glutamate metabolism. In a glucose-perfused, isolated rat heart model...... subjected to 40 min global no-flow ischaemia and 120 min reperfusion, the effects of IPC (2 cycles of 5 min ischaemia and 5 min reperfusion) and continuous glutamate (20 mm) administration during reperfusion on infarct size and haemodynamic recovery were studied. The effect of inhibiting amino acid...... transamination was evaluated by adding the amino acid transaminase inhibitor amino-oxyacetate (AOA; 0.025 mm) during reperfusion. Changes in coronary effluent, interstitial (microdialysis) and intracellular glutamate ([GLUT](i)) concentrations were measured. Ischaemic preconditioning and postischaemic glutamate...

  6. Enlarged Heart

    Science.gov (United States)

    ... rheumatic fever, a heart defect, infections (infectious endocarditis), connective tissue disorders, certain medications or radiation treatments for cancer, your heart may enlarge. Disease of the heart ...

  7. Wet cupping therapy restores sympathovagal imbalances in cardiac rhythm.

    Science.gov (United States)

    Arslan, Müzeyyen; Yeşilçam, Nesibe; Aydin, Duygu; Yüksel, Ramazan; Dane, Senol

    2014-04-01

    A recent study showed that cupping had therapeutic effects in rats with myocardial infarction and cardiac arrhythmias. The current studyaimed to investigate the possible useful effects of cupping therapy on cardiac rhythm in terms of heart rate variability (HRV). Forty healthy participants were included. Classic wet cupping therapy was applied on five points of the back. Recording electrocardiography (to determine HRV) was applied 1 hour before and 1 hour after cupping therapy. All HRV parameters increased after cupping therapy compared with before cupping therapy in healthy persons. These results indicate for the first time in humans that cupping might be cardioprotective. In this study, cupping therapy restored sympathovagal imbalances by stimulating the peripheral nervous system.

  8. Technical Note: A 3-D rendering algorithm for electromechanical wave imaging of a beating heart.

    Science.gov (United States)

    Nauleau, Pierre; Melki, Lea; Wan, Elaine; Konofagou, Elisa

    2017-09-01

    Arrhythmias can be treated by ablating the heart tissue in the regions of abnormal contraction. The current clinical standard provides electroanatomic 3-D maps to visualize the electrical activation and locate the arrhythmogenic sources. However, the procedure is time-consuming and invasive. Electromechanical wave imaging is an ultrasound-based noninvasive technique that can provide 2-D maps of the electromechanical activation of the heart. In order to fully visualize the complex 3-D pattern of activation, several 2-D views are acquired and processed separately. They are then manually registered with a 3-D rendering software to generate a pseudo-3-D map. However, this last step is operator-dependent and time-consuming. This paper presents a method to generate a full 3-D map of the electromechanical activation using multiple 2-D images. Two canine models were considered to illustrate the method: one in normal sinus rhythm and one paced from the lateral region of the heart. Four standard echographic views of each canine heart were acquired. Electromechanical wave imaging was applied to generate four 2-D activation maps of the left ventricle. The radial positions and activation timings of the walls were automatically extracted from those maps. In each slice, from apex to base, these values were interpolated around the circumference to generate a full 3-D map. In both cases, a 3-D activation map and a cine-loop of the propagation of the electromechanical wave were automatically generated. The 3-D map showing the electromechanical activation timings overlaid on realistic anatomy assists with the visualization of the sources of earlier activation (which are potential arrhythmogenic sources). The earliest sources of activation corresponded to the expected ones: septum for the normal rhythm and lateral for the pacing case. The proposed technique provides, automatically, a 3-D electromechanical activation map with a realistic anatomy. This represents a step towards a

  9. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F.

    2018-02-26

    Circadian rhythms enable organisms to synchronise the processes underpinning survival and reproduction to anticipate daily changes in the external environment. Recent work shows that daily (circadian) rhythms also enable parasites to maximise fitness in the context of ecological interactions with their hosts. Because parasite rhythms matter for their fitness, understanding how they are regulated could lead to innovative ways to reduce the severity and spread of diseases. Here, we examine how host circadian rhythms influence rhythms in the asexual replication of malaria parasites. Asexual replication is responsible for the severity of malaria and fuels transmission of the disease, yet, how parasite rhythms are driven remains a mystery. We perturbed feeding rhythms of hosts by 12 hours (i.e. diurnal feeding in nocturnal mice) to desynchronise the host’s peripheral oscillators from the central, light-entrained oscillator in the brain and their rhythmic outputs. We demonstrate that the rhythms of rodent malaria parasites in day-fed hosts become inverted relative to the rhythms of parasites in night-fed hosts. Our results reveal that the host’s peripheral rhythms (associated with the timing of feeding and metabolism), but not rhythms driven by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms resynchronise to the altered host feeding rhythms when food availability is shifted, which is not mediated through rhythms in the host immune system. Our observations suggest that parasites actively control their developmental rhythms. Finally, counter to expectation, the severity of disease symptoms expressed by hosts was not affected by desynchronisation of their central and peripheral rhythms. Our study at the intersection of disease ecology and chronobiology opens up a new

  10. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F

    2017-12-07

    Circadian rhythms enable organisms to synchronise the processes underpinning survival and reproduction to anticipate daily changes in the external environment. Recent work shows that daily (circadian) rhythms also enable parasites to maximise fitness in the context of ecological interactions with their hosts. Because parasite rhythms matter for their fitness, understanding how they are regulated could lead to innovative ways to reduce the severity and spread of diseases. Here, we examine how host circadian rhythms influence rhythms in the asexual replication of malaria parasites. Asexual replication is responsible for the severity of malaria and fuels transmission of the disease, yet, how parasite rhythms are driven remains a mystery. We perturbed feeding rhythms of hosts by 12 hours (i.e. diurnal feeding in nocturnal mice) to desynchronise the host\\'s peripheral oscillators from the central, light-entrained oscillator in the brain and their rhythmic outputs. We demonstrate that the rhythms of rodent malaria parasites in day-fed hosts become inverted relative to the rhythms of parasites in night-fed hosts. Our results reveal that the host\\'s peripheral rhythms (associated with the timing of feeding and metabolism), but not rhythms driven by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms resynchronise to the altered host feeding rhythms when food availability is shifted, which is not mediated through rhythms in the host immune system. Our observations suggest that parasites actively control their developmental rhythms. Finally, counter to expectation, the severity of disease symptoms expressed by hosts was not affected by desynchronisation of their central and peripheral rhythms. Our study at the intersection of disease ecology and chronobiology opens up a new

  11. Insuficiência cardíaca com fração de ejeção normal Insuficiencia cardíaca con fracción de eyección normal Heart failure with normal ejection fraction

    Directory of Open Access Journals (Sweden)

    Meliza Goi Roscani

    2010-05-01

    multifactoriales, involucrando la rigidez pasiva del miocardio, la geometría ventricular, la fuerza de contención pericárdica y la interacción entre los ventrículos. Los objetivos principales del tratamiento son reducir la congestión venosa pulmonar, la frecuencia cardíaca y controlar las comorbilidades. Todavía no hay evidencias de que el uso de medicaciones específicas, como inhibidores de la enzima de conversión o betabloqueadores, interfieran en la mortalidad. Los factores de peor pronóstico incluyen la edad avanzada, presencia de disfunción renal, diabetes, clase funcional III y IV (NYHA y estado avanzado de disfunción diastólica, con patrón restrictivo al llenado ventricular. Otro aspecto viene cobrando espacio en la bibliografía es el cuestionamiento del papel de la disfunción sistólica en los cuadros de ICFEN. Todos estos aspectos se abordan detalladamente en la presente revisión.Heart failure with normal ejection fraction (HFNEF is a complex syndrome that has been broadly studied since the last decade. It is caused by diastolic ventricular dysfunction demonstrated by complementary methods, such as hemodynamic study or echocardiogram, in the presence of a normal ejection fraction (EF. It affects primarily elderly individuals with comorbidities, such as systemic arterial hypertension, coronary failure and obesity. The physiopathological mechanisms are complex and multifactorial, involving the myocardial passive stiffness, the ventricular geometry, the pericardial restraint and the interaction between the ventricles. The main objectives of the treatment were to decrease the pulmonary venous congestion and the heart rate and control the comorbidities. There is no strong evidence that the use of specific medications, such as the angiotensin-converting enzyme inhibitors or beta-blockers can influence mortality. The poorer prognostic factors include advanced age, presence of kidney dysfunction, diabetes, functional class III and IV (NYHA and advanced

  12. Reproducibility and Angle Independence of Electromechanical Wave Imaging for the Measurement of Electromechanical Activation during Sinus Rhythm in Healthy Humans.

    Science.gov (United States)

    Melki, Lea; Costet, Alexandre; Konofagou, Elisa E

    2017-10-01

    Electromechanical wave imaging (EWI) is an ultrasound-based technique that can non-invasively map the transmural electromechanical activation in all four cardiac chambers in vivo. The objective of this study was to determine the reproducibility and angle independence of EWI for the assessment of electromechanical activation during normal sinus rhythm (NSR) in healthy humans. Acquisitions were performed transthoracically at 2000 frames/s on seven healthy human hearts in parasternal long-axis, apical four- and two-chamber views. EWI data was collected twice successively in each view in all subjects, while four successive acquisitions were obtained in one case. Activation maps were generated and compared (i) within the same acquisition across consecutive cardiac cycles; (ii) within same view across successive acquisitions; and (iii) within equivalent left-ventricular regions across different views. EWI was capable of characterizing electromechanical activation during NSR and of reliably obtaining similar patterns of activation. For consecutive heart cycles, the average 2-D correlation coefficient between the two isochrones across the seven subjects was 0.9893, with a mean average activation time fluctuation in LV wall segments across acquisitions of 6.19%. A mean activation time variability of 12% was obtained across different views with a measurement bias of only 3.2 ms. These findings indicate that EWI can map the electromechanical activation during NSR in human hearts in transthoracic echocardiography in vivo and results in reproducible and angle-independent activation maps. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  13. Thyrotoxicosis and the Heart – A Review of the Literature | Ogbera ...

    African Journals Online (AJOL)

    Thyrotoxicosis is a common endocrine disorder affecting more females than males. It is well known that one of the main complications of thyrotoxicosis is heart disease, including heart rhythm abnormalities. Studies have clearly shown that patients with hyperthyroidism are more likely to die from heart disease or stroke, ...

  14. Timing of food intake impacts daily rhythms of human salivary microbiota: a randomized, crossover study.

    Science.gov (United States)

    Collado, María Carmen; Engen, Phillip A; Bandín, Cristina; Cabrera-Rubio, Raúl; Voigt, Robin M; Green, Stefan J; Naqib, Ankur; Keshavarzian, Ali; Scheer, Frank A J L; Garaulet, Marta

    2018-04-01

    The composition of the diet (what we eat) has been widely related to the microbiota profile. However, whether the timing of food consumption (when we eat) influences microbiota in humans is unknown. A randomized, crossover study was performed in 10 healthy normal-weight young women to test the effect of the timing of food intake on the human microbiota in the saliva and fecal samples. More specifically, to determine whether eating late alters daily rhythms of human salivary microbiota, we interrogated salivary microbiota in samples obtained at 4 specific time points over 24 h, to achieve a better understanding of the relationship between food timing and metabolic alterations in humans. Results revealed significant diurnal rhythms in salivary diversity and bacterial relative abundance ( i.e., TM7 and Fusobacteria) across both early and late eating conditions. More importantly, meal timing affected diurnal rhythms in diversity of salivary microbiota toward an inverted rhythm between the eating conditions, and eating late increased the number of putative proinflammatory taxa, showing a diurnal rhythm in the saliva. In a randomized, crossover study, we showed for the first time the impact of the timing of food intake on human salivary microbiota. Eating the main meal late inverts the daily rhythm of salivary microbiota diversity which may have a deleterious effect on the metabolism of the host.-Collado, M. C., Engen, P. A., Bandín, C., Cabrera-Rubio, R., Voigt, R. M., Green, S. J., Naqib, A., Keshavarzian, A., Scheer, F. A. J. L., Garaulet, M. Timing of food intake impacts daily rhythms of human salivary microbiota: a randomized, crossover study.

  15. Nocturnal polyuria is related to absent circadian rhythm of glomerular filtration rate.

    Science.gov (United States)

    De Guchtenaere, A; Vande Walle, C; Van Sintjan, P; Raes, A; Donckerwolcke, R; Van Laecke, E; Hoebeke, P; Vande Walle, J

    2007-12-01

    Monosymptomatic nocturnal enuresis is frequently associated with nocturnal polyuria and low urinary osmolality during the night. Initial studies found decreased vasopressin levels associated with low urinary osmolality overnight. Together with the documented desmopressin response, this was suggestive of a primary role for vasopressin in the pathogenesis of enuresis in the absence of bladder dysfunction. Recent studies no longer confirm this primary role of vasopressin. Other pathogenetic factors such as disordered renal sodium handling, hypercalciuria, increased prostaglandins and/or osmotic excretion might have a role. So far, little attention has been given to abnormalities in the circadian rhythm of glomerular filtration rate. We evaluated the circadian rhythm of glomerular filtration rate and diuresis in children with desmopressin resistant monosymptomatic nocturnal enuresis and nocturnal polyuria. We evaluated 15 children (9 boys) 9 to 14 years old with monosymptomatic nocturnal enuresis and nocturnal polyuria resistant to desmopressin treatment. The control group consisted of 25 children (12 boys) 9 to 16 years old with monosymptomatic nocturnal enuresis without nocturnal polyuria. Compared to the control population, children with nocturnal polyuria lost their circadian rhythm not only for diuresis and sodium excretion but also for glomerular filtration rate. Patients with monosymptomatic nocturnal enuresis and nocturnal polyuria lack a normal circadian rhythm for diuresis and sodium excretion, and the circadian rhythm of glomerular filtration rate is absent. This absence of circadian rhythm of glomerular filtration rate and/or sodium handling cannot be explained by a primary role of vasopressin, but rather by a disorder in circadian rhythm of renal glomerular and/or tubular functions.

  16. The Restoration of Chronotropic CompEtence in Heart Failure PatientS with Normal Ejection FracTion (RESET) Study: Rationale and Design

    Science.gov (United States)

    Kass, David A.; Kitzman, Dalane W.; Alvarez, Guy E.

    2009-01-01

    Background Heart failure with preserved ejection fraction (HFpEF) is the predominant form of HF among the elderly and in women. However, there are few if any evidence-based therapeutic options for HFpEF. The chief complaint of HFpEF is reduced tolerance to physical exertion. Recent data revealed that one potential mechanism of exertional intolerance in HFpEF patients is inadequate chronotropic response. Although there is considerable evidence demonstrating the benefits of rate-adaptive pacing (RAP) provided from implantable cardiac devices in patients with an impaired chronotropic response, the effect of RAP in HFpEF is unknown. Methods and Results The RESET study is a prospective, multi-center, double-blind, randomized with stratification, study assessing the effect of RAP on peak VO2 and quality of life. RAP therapy will be evaluated in a cross-over paired fashion for each patient within each study stratum. Study strata are based on patient beta-blocker usage at time of enrollment. The study is powered to assess the impact of pacing independently in both strata. Conclusions The RESET study seeks to evaluate the potential benefit of RAP in patients with symptomatic mild to moderate HFpEF and chronotropic impairment. Study enrollment began in July 2008. PMID:20123314

  17. The effect of restraining on the heart rate in guinea pigs

    Science.gov (United States)

    Mikiskova, H.

    1980-01-01

    The emotional effect of different applications of electrodes and the fixation for cariographic examination was investigated using guinea pigs. The effect of the stress is discussed in terms of heart rhythm and behavior.

  18. Сircadian rhythm and metabolic effects of melatonin

    Directory of Open Access Journals (Sweden)

    Denis Igorevich Burchakov

    2015-02-01

    Full Text Available Sleep is a highly important process, required for normal organ and system function. Researchers assume, that during sleep brain shifts to internal body signals. Therefore, any sleep disturbance will disrupt health. Industrial and post-industrial society links high stress level and sleep problems. Excess light stimulation in living space, including bedroom, disorganize circadian rhythm of melatonin. Besides regulation this hormone has antioxidant and adaptogen functions. From psychological standpoint the same high-stress social context depletes the adaptation resources. To normalize sleep function we can utilize both sleep hygiene measures and modern pharmacotherapy. There are melatonin-based drugs, which help to restore sleep-wake cycle, augment adaptive capability and in some cases empower the existing treatment for specific somatic maladies. From a clinical and chronobiological standpoint melatonin is useful in broad spectrum of disorders.

  19. Mu rhythm desynchronization by tongue thrust observation

    Directory of Open Access Journals (Sweden)

    Kotoe eSakihara

    2015-09-01

    Full Text Available We aimed to investigate the mu rhythm in the sensorimotor area during tongue thrust observation and to obtain an answer to the question as to how subtle non-verbal orofacial movement observation activates the sensorimotor area. Ten healthy volunteers performed finger tap execution, tongue thrust execution, and tongue thrust observation. The electroencephalogram was recorded from 128 electrodes placed on the scalp, and regions of interest were set at sensorimotor areas. The event-related desynchronization (ERD and event-related synchronization (ERS for the mu rhythm (8–13 Hz and beta (13−25 Hz bands were measured. Tongue thrust observation induced mu rhythm ERD, and the ERD was detected at the left hemisphere regardless whether the observed tongue thrust was toward the left or right. Mu rhythm ERD was also recorded during tongue thrust execution. However, temporal analysis revealed that the ERD associated with tongue thrust observation preceded that associated with execution by approximately 2 s. Tongue thrust observation induces mu rhythm ERD in sensorimotor cortex with left hemispheric dominance.

  20. Circadian Rhythm Disruption Promotes Lung Tumorigenesis.

    Science.gov (United States)

    Papagiannakopoulos, Thales; Bauer, Matthew R; Davidson, Shawn M; Heimann, Megan; Subbaraj, Lakshmipriya; Bhutkar, Arjun; Bartlebaugh, Jordan; Vander Heiden, Matthew G; Jacks, Tyler

    2016-08-09

    Circadian rhythms are 24-hr oscillations that control a variety of biological processes in living systems, including two hallmarks of cancer, cell division and metabolism. Circadian rhythm disruption by shift work is associated with greater risk for cancer development and poor prognosis, suggesting a putative tumor-suppressive role for circadian rhythm homeostasis. Using a genetically engineered mouse model of lung adenocarcinoma, we have characterized the effects of circadian rhythm disruption on lung tumorigenesis. We demonstrate that both physiologic perturbation (jet lag) and genetic mutation of the central circadian clock components decreased survival and promoted lung tumor growth and progression. The core circadian genes Per2 and Bmal1 were shown to have cell-autonomous tumor-suppressive roles in transformation and lung tumor progression. Loss of the central clock components led to increased c-Myc expression, enhanced proliferation, and metabolic dysregulation. Our findings demonstrate that both systemic and somatic disruption of circadian rhythms contribute to cancer progression. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. [Dynamic Attending Binds Time and Rhythm Perception].

    Science.gov (United States)

    Kuroda, Tsuyoshi; Ono, Fuminori; Kadota, Hiroshi

    2017-11-01

    Relations between time and rhythm perception are discussed in this review of psychophysical research relevant to the multiple-look effect and dynamic-attending theory. Discrimination of two neighboring intervals that are marked by three successive sounds is improved when the presentation of the first (standard, S) interval is repeated before that of the second (comparison, C), as SSSSC. This improvement in sensitivity, called the multiple-look effect, occurs because listeners (1) perceive regular rhythm during the repetition of the standard interval, (2) predict the timing of subsequent sounds, and (3) detect sounds that are deviated from the predicted timing. The dynamic-attending theory attributes such predictions to the entrainment of attentional rhythms. An endogenous attentional rhythm is synchronized with the periodic succession of sounds marking the repeated standard. The standard and the comparison are discriminated on the basis of whether the ending marker of the comparison appears at the peak of the entrained attentional rhythm. This theory is compatible with the findings of recent neurophysiological studies that relate temporal prediction to neural oscillations.

  2. Daily Rhythms in Mobile Telephone Communication.

    Science.gov (United States)

    Aledavood, Talayeh; López, Eduardo; Roberts, Sam G B; Reed-Tsochas, Felix; Moro, Esteban; Dunbar, Robin I M; Saramäki, Jari

    2015-01-01

    Circadian rhythms are known to be important drivers of human activity and the recent availability of electronic records of human behaviour has provided fine-grained data of temporal patterns of activity on a large scale. Further, questionnaire studies have identified important individual differences in circadian rhythms, with people broadly categorised into morning-like or evening-like individuals. However, little is known about the social aspects of these circadian rhythms, or how they vary across individuals. In this study we use a unique 18-month dataset that combines mobile phone calls and questionnaire data to examine individual differences in the daily rhythms of mobile phone activity. We demonstrate clear individual differences in daily patterns of phone calls, and show that these individual differences are persistent despite a high degree of turnover in the individuals' social networks. Further, women's calls were longer than men's calls, especially during the evening and at night, and these calls were typically focused on a small number of emotionally intense relationships. These results demonstrate that individual differences in circadian rhythms are not just related to broad patterns of morningness and eveningness, but have a strong social component, in directing phone calls to specific individuals at specific times of day.

  3. Effects of exercise on circadian rhythms and mobility in aging Drosophila melanogaster.

    Science.gov (United States)

    Rakshit, Kuntol; Wambua, Rebecca; Giebultowicz, Tomasz M; Giebultowicz, Jadwiga M

    2013-11-01

    Daily life functions such as sleep and feeding oscillate with circa 24 h period due to endogenous circadian rhythms generated by circadian clocks. Genetic or environmental disruption of circadian rhythms is associated with various aging-related phenotypes. Circadian rhythms decay during normal aging, and there is a need to explore strategies that could avert age-related changes in the circadian system. Exercise was reported to delay aging in mammals. Here, we investigated whether daily exercise via stimulation of upward climbing movement could improve circadian rest/activity rhythms in aging Drosophila melanogaster. We found that repeated exercise regimen did not strengthen circadian locomotor activity rhythms in aging flies and had no effect on their lifespan. We also tested the effects of exercise on mobility and determined that regular exercise lowered age-specific climbing ability in both wild type and clock mutant flies. Interestingly, the climbing ability was most significantly reduced in flies carrying a null mutation in the core clock gene period, while rescue of this gene significantly improved climbing to wild type levels. Our work highlights the importance of period in sustaining endurance in aging flies exposed to physical challenge. © 2013.

  4. Effect of Spaceflight on the Circadian Rhythm, Lifespan and Gene Expression of Drosophila melanogaster

    Science.gov (United States)

    Xu, Kanyan

    2015-01-01

    Space travelers are reported to experience circadian rhythm disruption during spaceflight. However, how the space environment affects circadian rhythm is yet to be determined. The major focus of this study was to investigate the effect of spaceflight on the Drosophila circadian clock at both the behavioral and molecular level. We used China’s Shenzhou-9 spaceship to carry Drosophila. After 13 days of spaceflight, behavior tests showed that the flies maintained normal locomotor activity rhythm and sleep pattern. The expression level and rhythm of major clock genes were also unaffected. However, expression profiling showed differentially regulated output genes of the circadian clock system between space flown and control flies, suggesting that spaceflight affected the circadian output pathway. We also investigated other physiological effects of spaceflight such as lipid metabolism and lifespan, and searched genes significantly affected by spaceflight using microarray analysis. These results provide new information on the effects of spaceflight on circadian rhythm, lipid metabolism and lifespan. Furthermore, we showed that studying the effect of spaceflight on gene expression using samples collected at different Zeitgeber time could obtain different results, suggesting the importance of appropriate sampling procedures in studies on the effects of spaceflight. PMID:25798821

  5. Effect of spaceflight on the circadian rhythm, lifespan and gene expression of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Lingling Ma

    Full Text Available Space travelers are reported to experience circadian rhythm disruption during spaceflight. However, how the space environment affects circadian rhythm is yet to be determined. The major focus of this study was to investigate the effect of spaceflight on the Drosophila circadian clock at both the behavioral and molecular level. We used China's Shenzhou-9 spaceship to carry Drosophila. After 13 days of spaceflight, behavior tests showed that the flies maintained normal locomotor activity rhythm and sleep pattern. The expression level and rhythm of major clock genes were also unaffected. However, expression profiling showed differentially regulated output genes of the circadian clock system between space flown and control flies, suggesting that spaceflight affected the circadian output pathway. We also investigated other physiological effects of spaceflight such as lipid metabolism and lifespan, and searched genes significantly affected by spaceflight using microarray analysis. These results provide new information on the effects of spaceflight on circadian rhythm, lipid metabolism and lifespan. Furthermore, we showed that studying the effect of spaceflight on gene expression using samples collected at different Zeitgeber time could obtain different results, suggesting the importance of appropriate sampling procedures in studies on the effects of spaceflight.

  6. The maturation of cortical sleep rhythms and networks over early development.

    Science.gov (United States)

    Chu, C J; Leahy, J; Pathmanathan, J; Kramer, M A; Cash, S S

    2014-07-01

    Although neuronal activity drives all aspects of cortical development, how human brain rhythms spontaneously mature remains an active area of research. We sought to systematically evaluate the emergence of human brain rhythms and functional cortical networks over early development. We examined cortical rhythms and coupling patterns from birth through adolescence in a large cohort of healthy children (n=384) using scalp electroencephalogram (EEG) in the sleep state. We found that the emergence of brain rhythms follows a stereotyped sequence over early development. In general, higher frequencies increase in prominence with striking regional specificity throughout development. The coordination of these rhythmic activities across brain regions follows a general pattern of maturation in which broadly distributed networks of low-frequency oscillations increase in density while networks of high frequency oscillations become sparser and more highly clustered. Our results indicate that a predictable program directs the development of key rhythmic components and physiological brain networks over early development. This work expands our knowledge of normal cortical development. The stereotyped neurophysiological processes observed at the level of rhythms and networks may provide a scaffolding to support critical periods of cognitive growth. Furthermore, these conserved patterns could provide a sensitive biomarker for cortical health across development. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  7. Cancer Clocks Out for Lunch: Disruption of Circadian Rhythm and Metabolic Oscillation in Cancer.

    Science.gov (United States)

    Altman, Brian J

    2016-01-01

    Circadian rhythms are 24-h oscillations present in most eukaryotes and many prokaryotes that synchronize activity to the day-night cycle. They are an essential feature of organismal and cell physiology that coordinate many of the metabolic, biosynthetic, and signal transduction pathways studied in biology. The molecular mechanism of circadian rhythm is controlled both by signal transduction and gene transcription as well as by metabolic feedback. The role of circadian rhythm in cancer cell development and survival is still not well understood, but as will be discussed in this Review, accumulated research suggests that circadian rhythm may be altered or disrupted in many human cancers downstream of common oncogenic alterations. Thus, a complete understanding of the genetic and metabolic alterations in cancer must take potential circadian rhythm perturbations into account, as this disruption itself will influence how gene expression and metabolism are altered in the cancer cell compared to its non-transformed neighbor. It will be important to better understand these circadian changes in both normal and cancer cell physiology to potentially design treatment modalities to exploit this insight.

  8. Mozart, Mozart Rhythm and Retrograde Mozart Effects: Evidences from Behaviours and Neurobiology Bases.

    Science.gov (United States)

    Xing, Yingshou; Xia, Yang; Kendrick, Keith; Liu, Xiuxiu; Wang, Maosen; Wu, Dan; Yang, Hua; Jing, Wei; Guo, Daqing; Yao, Dezhong

    2016-01-21

    The phenomenal finding that listening to Mozart K.448 enhances performance on spatial tasks has motivated a continuous surge in promoting music education over the past two decades. But there have been inconsistent reports in previous studies of the Mozart effect. Here conducted was a systematic study, with Mozart and retrograde Mozart music, Mozart music rhythm and pitch, behaviours and neurobiology tests, rats and humans subjects. We show that while the Mozart K.448 has positive cognitive effects, the retrograde version has a negative effect on rats' performance in the Morris water maze test and on human subjects' performance in the paper folding and cutting test and the pencil-and-paper maze test. Such findings are further confirmed by subsequent immunohistochemical analyses in rats on the neurogenesis and protein levels of BDNF and its receptor, TrkB. Furthermore, when the rhythm and pitch of the normal and retrograde Mozart music are manipulated independently, the learning performance of the rats in the Morris water maze test indicated that rhythm is a crucial element in producing the behavioural effects. These findings suggest that the nature of Mozart effect is the Mozart rhythm effect, and indicate that different music may have quite different to opposite effects. Further study on rhythm effect may provide clues to understand the common basis over animals from rats to humans.

  9. Effects of continuous triiodothyronine infusion on the tricarboxylic acid cycle in the normal immature swine heart under extracorporeal membrane oxygenation in vivo.

    Science.gov (United States)

    Kajimoto, Masaki; Priddy, Colleen M O'Kelly; Ledee, Dolena R; Xu, Chun; Isern, Nancy; Olson, Aaron K; Portman, Michael A

    2014-04-15

    Extracorporeal membrane oxygenation (ECMO) is frequently used in infants with postoperative cardiopulmonary failure. ECMO also suppresses circulating triiodothyronine (T3) levels and modifies myocardial metabolism. We assessed the hypothesis that T3 supplementation reverses ECMO-induced metabolic abnormalities in the immature heart. Twenty-two male Yorkshire pigs (age: 25-38 days) with ECMO received [2-(13)C]lactate, [2,4,6,8-(13)C4]octanoate (medium-chain fatty acid), and [U-(13)C]long-chain fatty acids as metabolic tracers either systemically (totally physiological intracoronary concentration) or directly into the coronary artery (high substrate concentration) for the last 60 min of each protocol. NMR analysis of left ventricular tissue determined the fractional contribution of these substrates to the tricarboxylic acid cycle. Fifty percent of the pigs in each group received intravenous T3 supplement (bolus at 0.6 μg/kg and then continuous infusion at 0.2 μg·kg(-1)·h(-1)) during ECMO. Under both substrate loading conditions, T3 significantly increased the fractional contribution of lactate with a marginal increase in the fractional contribution of octanoate. Both T3 and high substrate provision increased the myocardial energy status, as indexed by phosphocreatine concentration/ATP concentration. In conclusion, T3 supplementation promoted lactate metabolism to the tricarboxylic acid cycle during ECMO, suggesting that T3 releases the inhibition of pyruvate dehydrogenase. Manipulation of substrate utilization by T3 may be used therapeutically during ECMO to improve the resting energy state and facilitate weaning.

  10. Melatonin secretion is impaired in women with preeclampsia and an abnormal circadian blood pressure rhythm.

    Science.gov (United States)

    Bouchlariotou, Sofia; Liakopoulos, Vassilios; Giannopoulou, Myrto; Arampatzis, Spyridon; Eleftheriadis, Theodoros; Mertens, Peter R; Zintzaras, Elias; Messinis, Ioannis E; Stefanidis, Ioannis

    2014-08-01

    Non-dipping circadian blood pressure (BP) is a common finding in preeclampsia, accompanied by adverse outcomes. Melatonin plays pivotal role in biological circadian rhythms. This study investigated the relationship between melatonin secretion and circadian BP rhythm in preeclampsia. Cases were women with preeclampsia treated between January 2006 and June 2007 in the University Hospital of Larissa. Volunteers with normal pregnancy, matched for chronological and gestational age, served as controls. Twenty-four hour ambulatory BP monitoring was applied. Serum melatonin and urine 6-sulfatoxymelatonin levels were determined in day and night time samples by enzyme-linked immunoassays. Measurements were repeated 2 months after delivery. Thirty-one women with preeclampsia and 20 controls were included. Twenty-one of the 31 women with preeclampsia were non-dippers. Compared to normal pregnancy, in preeclampsia there were significantly lower night time melatonin (48.4 ± 24.7 vs. 85.4 ± 26.9 pg/mL, pcircadian BP rhythm status ascribed this finding exclusively to non-dippers (pcircadian BP and melatonin secretion rhythm reappeared. In contrast, in cases with retained non-dipping status (n=10) melatonin secretion rhythm remained impaired: daytime versus night time melatonin (33.5 ± 13.0 vs. 28.0 ± 13.8 pg/mL, p=0.386). Urinary 6-sulfatoxymelatonin levels were, overall, similar to serum melatonin. Circadian BP and melatonin secretion rhythm follow parallel course in preeclampsia, both during pregnancy and, at least 2 months after delivery. Our findings may be not sufficient to implicate a putative therapeutic effect of melatonin, however, they clearly emphasize that its involvement in the pathogenesis of a non-dipping BP in preeclampsia needs intensive further investigation.

  11. Daily Socs1 rhythms alter with aging differentially in peripheral clocks in male Wistar rats: therapeutic effects of melatonin.

    Science.gov (United States)

    Vinod, Ch; Jagota, Anita

    2017-06-01

    Suprachiasmatic nucleus (SCN) in synchronization with the peripheral clocks regulates the temporal oscillations leading to overt rhythms. Aging leads to attenuation of such circadian regulation, accompanied by increased inflammatory mediators prevalently the cytokines. Suppressors of cytokine signaling (SOCS) family of proteins such as SOCS 1, 3 and cytokine-inducible SH2-containing protein (CIS) negatively regulate the cytokine signaling pathway. The role of SOCS1 in aging and circadian system is obscure. We therefore studied the daily rhythms of rSocs1 mRNA expression at Zeitgeber time (ZT) -0, 6, 12 and 18 in peripheral clocks such as liver, kidney, intestine and heart of 3, 12 and 24 months (m) old male Wistar rats. Interestingly the peripheral clocks studied displayed a rhythmic rSocs1 gene expression in 3 months. In 12 months group, 12 h phase advance in liver and 12 h phase delay in kidney and heart was observed with abolition of rhythms in intestine. Aging (24 months group) resulted in a phase advance by 6 h in liver and heart with abolition of rhythms in intestine in 24 months group. Kidney was also significantly affected upon aging with significant decrease in the rSocs1 levels and abolition of rhythms. The decrease in melatonin levels with aging is associated with decreased immunity and increased oxidative stress. The exogenous administration of melatonin has been linked to play a role in re-synchronization of circadian rhythms, reducing oxidative stress and enhancing immune properties. We therefore had studied the effect of exogenous melatonin upon age induced changes in daily rSocs1 gene expression patterns. Melatonin treatment partially restored the rhythms and daily pulse (ratio of maximum:minimum levels) in liver and intestine in 12 months group. Melatonin administration resulted in a significant increase in mean 24 h rSocs1 expression in intestine and heart of 24 months group compared to that of 3 months. The melatonin administration

  12. Beating Heart Motion Accurate Prediction Method Based on Interactive Multiple Model: An Information Fusion Approach

    Science.gov (United States)

    Xie, Weihong; Yu, Yang

    2017-01-01

    Robot-assisted motion compensated beating heart surgery has the advantage over the conventional Coronary Artery Bypass Graft (CABG) in terms of reduced trauma to the surrounding structures that leads to shortened recovery time. The severe nonlinear and diverse nature of irregular heart rhythm causes enormous difficulty for the robot to realize the clinic requirements, especially under arrhythmias. In this paper, we propose a fusion prediction framework based on Interactive Multiple Model (IMM) estimator, allowing each model to cover a distinguishing feature of the heart motion in underlying dynamics. We find that, at normal state, the nonlinearity of the heart motion with slow time-variant changing dominates the beating process. When an arrhythmia occurs, the irregularity mode, the fast uncertainties with random patterns become the leading factor of the heart motion. We deal with prediction problem in the case of arrhythmias by estimating the state with two behavior modes which can adaptively “switch” from one to the other. Also, we employed the signal quality index to adaptively determine the switch transition probability in the framework of IMM. We conduct comparative experiments to evaluate the proposed approach with four distinguished datasets. The test results indicate that the new proposed approach reduces prediction errors significantly. PMID:29124062

  13. Beating Heart Motion Accurate Prediction Method Based on Interactive Multiple Model: An Information Fusion Approach

    Directory of Open Access Journals (Sweden)

    Fan Liang

    2017-01-01

    Full Text Available Robot-assisted motion compensated beating heart surgery has the advantage over the conventional Coronary Artery Bypass Graft (CABG in terms of reduced trauma to the surrounding structures that leads to shortened recovery time. The severe nonlinear and diverse nature of irregular heart rhythm causes enormous difficulty for the robot to realize the clinic requirements, especially under arrhythmias. In this paper, we propose a fusion prediction framework based on Interactive Multiple Model (IMM estimator, allowing each model to cover a distinguishing feature of the heart motion in underlying dynamics. We find that, at normal state, the nonlinearity of the heart motion with slow time-variant changing dominates the beating process. When an arrhythmia occurs, the irregularity mode, the fast uncertainties with random patterns become the leading factor of the heart motion. We deal with prediction problem in the case of arrhythmias by estimating the state with two behavior modes which can adaptively “switch” from one to the other. Also, we employed the signal quality index to adaptively determine the switch transition probability in the framework of IMM. We conduct comparative experiments to evaluate the proposed approach with four distinguished datasets. The test results indicate that the new proposed approach reduces prediction errors significantly.

  14. Tachycardiomyopathy: a reversible little known cause of heart failure = Taquicardiomiopatía: una causa reversible y poco reconocida de falla cardíaca

    Directory of Open Access Journals (Sweden)

    Tamayo Artunduaga, Natalia

    2014-01-01

    Full Text Available We report the case of a 74 year-old woman with heart failure syndrome, history of coronary artery disease with percutaneous revascularization and atrial flutter with rapid ventricular response without adequate control with beta-blockers and antiarrhythmic therapy, dilated left ventricle with impaired systolic function and ejection fraction of 18%; she had stent restenosis in the left anterior descending and the circumflex arteries. Medicated stents were implanted. Successful electrical cardioversion was performed and four weeks later she remained in sinus rhythm; ventricular function was normalized with ejection fraction of 60%, which corroborated the presumptive diagnosis of tachycardiomyopathy.

  15. Daily rhythms of the sleep-wake cycle

    Directory of Open Access Journals (Sweden)

    Waterhouse Jim

    2012-03-01

    Full Text Available Abstract The amount and timing of sleep and sleep architecture (sleep stages are determined by several factors, important among which are the environment, circadian rhythms and time awake. Separating the roles played by these factors requires specific protocols, including the constant routine and altered sleep-wake schedules. Results from such protocols have led to the discovery of the factors that determine the amounts and distribution of slow wave and rapid eye movement sleep as well as to the development of models to determine the amount and timing of sleep. One successful model postulates two processes. The first is process S, which is due to sleep pressure (and increases with time awake and is attributed to a 'sleep homeostat'. Process S reverses during slow wave sleep (when it is called process S'. The second is process C, which shows a daily rhythm that is parallel to the rhythm of core temperature. Processes S and C combine approximately additively to determine the times of sleep onset and waking. The model has proved useful in describing normal sleep in adults. Current work aims to identify the detailed nature of processes S and C. The model can also be applied to circumstances when the sleep-wake cycle is different from the norm in some way. These circumstances include: those who are poor sleepers or short sleepers; the role an individual's chronotype (a measure of how the timing of the individual's preferred sleep-wake cycle compares with the average for a population; and changes in the sleep-wake cycle with age, particularly in adolescence and aging, since individuals tend to prefer to go to sleep later during adolescence and earlier in old age. In all circumstances, the evidence that sleep times and architecture are altered and the possible causes of these changes (including altered S, S' and C processes are examined.

  16. Influence of forced respiration on nonlinear dynamics in heart rate variability

    DEFF Research Database (Denmark)

    Kanters, J K; Højgaard, M V; Agner, E

    1997-01-01

    Although it is doubtful whether the normal sinus rhythm can be described as low-dimensional chaos, there is evidence for inherent nonlinear dynamics and determinism in time series of consecutive R-R intervals. However, the physiological origin for these nonlinearities is unknown. The aim...... with a metronome set to 12 min(-1). Nonlinear dynamics were measured as the correlation dimension and the nonlinear prediction error. Complexity expressed as correlation dimension was unchanged from normal respiration, 9.1 +/- 0.5, compared with forced respiration, 9.3 +/- 0.6. Also, nonlinear determinism...... expressed as the nonlinear prediction error did not differ between spontaneous respiration, 32.3 +/- 3.4 ms, and forced respiration, 31.9 +/- 5.7. It is concluded that the origin of the nonlinear dynamics in heart rate variability is not a nonlinear input from the respiration into the cardiovascular...

  17. Circadian rhythm in QT interval is preserved in mice deficient of potassium channel interacting protein 2.

    Science.gov (United States)

    Gottlieb, Lisa A; Lubberding, Anniek; Larsen, Anders Peter; Thomsen, Morten B

    2017-01-01

    Potassium Channel Interacting Protein 2 (KChIP2) is suggested to be responsible for the circadian rhythm in repolarization duration, ventricular arrhythmias, and sudden cardiac death. We investigated the hypothesis that there is no circadian rhythm in QT interval in the absence of KChIP2. Implanted telemetric devices recorded electrocardiogram continuously for 5 days in conscious wild-type mice (WT, n = 9) and KChIP2 -/- mice (n = 9) in light:dark periods and in complete darkness. QT intervals were determined from all RR intervals and corrected for heart rate (QT 100 = QT/(RR/100) 1/2 ). Moreover, QT intervals were determined from complexes within the RR range of mean-RR ± 1% in the individual mouse (QT mean-RR ). We find that RR intervals are 125 ± 5 ms in WT and 123 ± 4 ms in KChIP2 -/- (p = 0.81), and QT intervals are 52 ± 1 and 52 ± 1 ms, respectively(p = 0.89). No ventricular arrhythmias or sudden cardiac deaths were observed. We find similar diurnal (light:dark) and circadian (darkness) rhythms of RR intervals in WT and KChIP2 -/- mice. Circadian rhythms in QT 100 intervals are present in both groups, but at physiological small amplitudes: 1.6 ± 0.2 and 1.0 ± 0.3 ms in WT and KChIP2 -/- , respectively (p = 0.15). A diurnal rhythm in QT 100 intervals was only found in WT mice. QT mean-RR intervals display clear diurnal and circadian rhythms in both WT and KChIP2 -/- . The amplitude of the circadian rhythm in QT mean-RR is 4.0 ± 0.3 and 3.1 ± 0.5 ms in WT and KChIP2 -/- , respectively (p = 0.16). In conclusion, KChIP2 expression does not appear to underlie the circadian rhythm in repolarization duration.

  18. Circadian Rhythm Sleep-Wake Disorders.

    Science.gov (United States)

    Abbott, Sabra M; Reid, Kathryn J; Zee, Phyllis C

    2015-12-01

    The circadian system regulates the timing and expression of nearly all biological processes, most notably, the sleep-wake cycle, and disruption of this system can result in adverse effects on both physical and mental health. The circadian rhythm sleep-wake disorders (CRSWDs) consist of 5 disorders that are due primarily to pathology of the circadian clock or to a misalignment of the timing of the endogenous circadian rhythm with the environment. This article outlines the nature of these disorders, the association of many of these disorders with psychiatric illness, and available treatment options. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. The importance of biological rhythms in drug treatment of hypertension and sex-dependent modifications

    Directory of Open Access Journals (Sweden)

    Lemmer B

    2012-04-01

    Full Text Available Björn LemmerInstitute of Experimental and Clinical Pharmacology and Toxicology, Ruprecht-Karls-University of Heidelberg, Mannheim, GermanyAbstract: The cardiovascular system is highly organized in time. Blood pressure, heart rate, peripheral resistance, pressure, and vasodilating hormones display pronounced circadian variations. New data presented here demonstrate also sex-dependent differences in vasodilating hormones, with higher NOχ excretion in females than males and a steeper early morning rise in norepinephrine in males, whereas the 24-hour blood pressure and heart-rate profiles were not different. Various antihypertensive drugs were investigated in crossover studies – morning versus evening dosing – in hypertensive patients; however, consistent data were only described for angiotensin-converting-enzyme (ACE inhibitors, calcium channel blockers, and angiotensin II type 1 (AT1 receptor blockers. Whereas in dippers ACE inhibitors had a superdipping effect when dosed at night, no difference in the blood pressure lowering effect or on the 24-hour blood pressure profile was found with calcium channel blockers after morning and evening dosing. In nondippers, the calcium channel blockers isradipine and amlodipine transformed nondippers into dippers, similar after evening dosing. The effects of AT1-receptor blockers are similar to those of ACE inhibitors. Also, diuretics are able to normalize non dipping behavior. Moreover, a circadian phase dependency in their pharmacokinetics has been demonstrated for various cardiovascular-active drugs, such as beta blockers, calcium channel blockers, oral nitrates, and ACE inhibitors, modified by the galenic formulation. There is evidence that in hypertensive dippers, antihypertensive drugs should be given during early morning hours, whereas in non dippers it can be necessary to add an evening dose or even to apply a single evening dose in order not only to reduce high blood pressure, but also to

  20. [Echocardiographic factors predictive of restoration and maintenance of sinus rhythm after reduction of atrial fibrillation].

    Science.gov (United States)

    Ben Khalfallah, A; Sanaa, I

    2007-09-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. While the arrhythmia was initially thought to be little more than a nuisance, it is now clear that AF has a significant negative impact on quality of life and a corresponding increase in both morbidity and mortality. The aim of this study was to identify Doppler echographic patterns that allow prediction of atrial fibrillation reduction and maintenance of sinus rhythm within 12 months. One hundred and thirty patients having permanent atrial fibrillation, recent (51) or chronic (79) are included in the study, excepting those with valvular heart disease or thyroid dysfunction. The mean age was 63.5 +/- 11.3 years. Both transthoracic and transoesophageal echocardiography was performed using a Philips SONOS 5500 Echograph, before cardioversion. Were studied: end diastolic and systolic left ventricular diameters, left ventricular ejectionnal fraction, left atrial area (LAA), left atrial diameter, left atrial appendage area and peak emptying velocities of the left atrial appendage (PeV). Sinus rhythm was re-established in 102 patients (44 having recent and 58 chronic atrial fibrillation). Sinus rhythm was maintained for 12 months in 79 patients. Within the echographic parameters studied, the left atrial area (LAA) and peak emptying velocities of left atrial appendage (PeV) before cardioversion were the best predictors of restoration of sinus rhythm. On monovariate analysis, SOG is significantly lower and PicV is significantly higher in patients whose sinus rhythm had been restored in comparison with those with permanent atrial fibrillation. (Mean SOG: 27.7 +/- 7.62 vs. 34 +/- 7,6 cm2, ppredict on mono and multivariate analysis (p=0.05, OR=0.5, IC=0.36 à 3.56), re-establishing of sinus rhythm whereas in patients with chronic atrial fibrillation, peak emptying velocity of left atrial appendage predict better re-establishing of sinus rhythm (p=0.04, OR=1.29, IC=0.12 à 4.23). The threshold values of LAA and Pe

  1. Adjustment of sleep and the circadian temperature rhythm after flights across nine time zones

    Science.gov (United States)

    Gander, Philippa H.; Myhre, Grete; Graeber, R. Curtis; Lauber, John K.; Andersen, Harald T.

    1989-01-01

    The adjustment of sleep-wake patterns and the circadian temperature rhythm was monitored in nine Royal Norwegian Airforce volunteers operating P-3 aircraft during a westward training deployment across nine time zones. Subjects recorded all sleep and nap times, rated nightly sleep quality, and completed personality inventories. Rectal temperature, heart rate, and wrist activity were continuously monitored. Adjustment was slower after the return eastward flight than after the outbound westward flight. The eastward flight produced slower readjustment of sleep timing to local time and greater interindividual variability in the patterns of adjustment of sleep and temperature. One subject apparently exhibited resynchronization by partition, with the temperature rhythm undergoing the reciprocal 15-h delay. In contrast, average heart rates during sleep were significantly elevated only after westward flight. Interindividual differences in adjustment of the temperature rhythm were correlated with some of the personality measures. Larger phase delays in the overall temperature waveform (as measured on the 5th day after westward flight) were exhibited by extraverts, and less consistently by evening types.

  2. Rhythm perception and production predict reading abilities in developmental dyslexia

    Directory of Open Access Journals (Sweden)

    Elena eFlaugnacco

    2014-06-01

    Full Text Available Rhythm organizes events in time and plays a major role in music, but also in the phonology and prosody of a language. Interestingly, children with developmental dyslexia - a learning disability that affects reading acquisition despite normal intelligence and adequate education - have a poor rhythmic perception. It has been suggested that an accurate perception of rhythmical/metrical structure, that requires accurate perception of rise time, may be critical for phonological development and subsequent literacy. This hypothesis is mostly based on results showing a high degree of correlation between phonological awareness and metrical skills, using a very specific metrical task. We present new findings from the analysis of a sample of 48 children with a diagnosis of dyslexia, without comorbidities. These children were assessed with neuropsychological tests, as well as specifically-devised psychoacoustic and musical tasks mostly testing temporal abilities. Associations were tested by multivariate analyses including data mining strategies, correlations and most importantly logistic regressions to understand to what extent the different auditory and musical skills can be a robust predictor of reading and phonological skills. Results show a strong link between several temporal skills and phonological and reading abilities. These findings are discussed in the framework of the neuroscience literature comparing music and language processing, with a particular interest in the links between rhythm processing in music and language.

  3. Weight Rhythms: Weight Increases during Weekends and Decreases during Weekdays

    Directory of Open Access Journals (Sweden)

    Anna-Leena Orsama

    2014-01-01

    Full Text Available Background/Aims: The week's cycle influences sleep, exercise, and eating habits. An accurate description of weekly weight rhythms has not been reported yet - especially across people who lose weight versus those who maintain or gain weight. Methods: The daily weight in 80 adults (BMI 20.0-33.5 kg/m2; age, 25-62 years was recorded and analysed to determine if a group-level weekly weight fluctuation exists. This was a retrospective study of 4,657 measurements during 15-330 monitoring days. Semi-parametric regression was used to model the rhythm. Results: A pattern of daily weight changes was found (p Conclusion: Weight variations between weekends and weekdays should be considered as normal instead of signs of weight gain. Those who compensate the most are most likely to either lose or maintain weight over time. Long-term habits may make more of a difference than short-term splurges. People prone to weight gain could be counselled about the importance of weekday compensation.

  4. Familial circadian rhythm disorder in the diurnal primate, Macaca mulatta.

    Directory of Open Access Journals (Sweden)

    Irina V Zhdanova

    Full Text Available In view of the inverse temporal relationship of central clock activity to physiological or behavioral outputs in diurnal and nocturnal species, understanding the mechanisms and physiological consequences of circadian disorders in humans would benefit from studies in a diurnal animal model, phylogenetically close to humans. Here we report the discovery of the first intrinsic circadian disorder in a family of diurnal non-human primates, the rhesus monkey. The disorder is characterized by a combination of delayed sleep phase, relative to light-dark cycle, mutual desynchrony of intrinsic rhythms of activity, food intake and cognitive performance, enhanced nighttime feeding or, in the extreme case, intrinsic asynchrony. The phenotype is associated with normal length of intrinsic circadian period and requires an intact central clock, as demonstrated by an SCN lesion. Entrainment to different photoperiods or melatonin administration does not eliminate internal desynchrony, though melatonin can temporarily reinstate intrinsic activity rhythms in the animal with intrinsic asynchrony. Entrainment to restricted feeding is highly effective in animals with intrinsic or SCN lesion-induced asynchrony. The large isolated family of rhesus macaques harboring the disorder provides a powerful new tool for translational research of regulatory circuits underlying circadian disorders and their effective treatment.

  5. Circadian rhythm and sleep influences on digestive physiology and disorders

    OpenAIRE

    Vaughn, Bradley; Rotolo,Sean; Roth,Heidi

    2014-01-01

    Bradley V Vaughn, Sean Rotolo, Heidi L Roth Division of Sleep Medicine, Department of Neurology, University of North Carolina School of Medicine, Chapel Hill, NC, USA Abstract: Circadian rhythms and sleep influence a variety of physiological functions, including the digestive system. The digestive system also has intrinsic rhythms that interact dynamically with circadian rhythms. New advances in understanding the interaction of these rhythms and sleep provide the prospect of evaluating their...

  6. Circadian Rhythm Regulates Development of Enamel in Mouse Mandibular First Molar

    Science.gov (United States)

    Tao, Jiang; Zhai, Yue; Park, Hyun; Han, Junli; Dong, Jianhui; Xie, Ming; Gu, Ting; Lewi, Keidren; Ji, Fang; Jia, William

    2016-01-01

    Rhythmic incremental growth lines and the presence of melatonin receptors were discovered in tooth enamel, suggesting possible role of circadian rhythm. We therefore hypothesized that circadian rhythm may regulate enamel formation through melatonin receptors. To test this hypothesis, we examined expression of melatonin receptors (MTs) and amelogenin (AMELX), a maker of enamel formation, during tooth germ development in mouse. Using qRT-PCR and immunocytochemistry, we found that mRNA and protein levels of both MTs and AMELX in normal mandibular first molar tooth germs increased gradually after birth, peaked at 3 or 4 day postnatal, and then decreased. Expression of MTs and AMELX by immunocytochemistry was significantly delayed in neonatal mice raised in all-dark or all-light environment as well as the enamel development. Furthermore, development of tooth enamel was also delayed showing significant immature histology in those animals, especially for newborn mice raised in all daylight condition. Interestingly, disruption in circadian rhythm in pregnant mice also resulted in delayed enamel development in their babies. Treatment with melatonin receptor antagonist 4P-PDOT in pregnant mice caused underexpression of MTs and AMELX associated with long-lasting deficiency in baby enamel tissue. Electromicroscopic evidence demonstrated increased necrosis and poor enamel mineralization in ameloblasts. The above results suggest that circadian rhythm is important for normal enamel development at both pre- and postnatal stages. Melatonin receptors were partly responsible for the regulation. PMID:27494172

  7. New Procedure for Treatment of Atrial Fibrillation in Patients with Valvular Heart Disease

    Directory of Open Access Journals (Sweden)

    Naser Safaie

    2010-10-01

    Full Text Available Patients with valvular heart disease suffer from atrial fibrillation for more than 12 months after valve surgery and have a low probability of remaining in sinus rhythm. We performed an intra-operative procedure similar to surgical maze ІІІ procedure for conversion of this arrhythmia to sinus rhythm. We did this study to evaluate the efficacy of this procedure to restore the sinus rhythm in patients with valvular heart disease. 28 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant reduction of left and right atrial size and resection of both atrial auricles in Shahid Madani cardiothoracic center from September 2004 to October 2008. The procedure for atrial fibrillation treatment was performed with cardiopulmonary bypass and after mitral valve replacement. There was one in-hospital death postoperatively because of respiratory failure, but no other complication till 6 months after the operation. Out of 28 patients, 23 were in sinus rhythm one week after the operation, one patient had junctional rhythm after the operation that restored to sinus rhythm and 4 patients had persistent atrial fibrillation. During the 12-month follow up, atrial fibrillation was corrected in 82.14%. Doppler echocardiography in these patients with sinus rhythm demonstrated good atrial contractility. This procedure on both atria is effective and less invasive than the original maze procedure to eliminate the atrial fibrillation, and can be performed in patients with valvular heart disease without increasing the risk of operation.

  8. New Procedure for Treatment of Atrial Fibrillation in Patients with Valvular Heart Disease

    Directory of Open Access Journals (Sweden)

    Naser Safaie

    2010-09-01

    Full Text Available "nPatients with valvular heart disease suffer from atrial fibrillation for more than 12 months after valve surgery and have a low probability of remaining in sinus rhythm. We performed an intra-operative procedure similar to surgical maze ІІІ procedure for conversion of this arrhythmia to sinus rhythm. We did this study to evaluate the efficacy of this procedure to restore the sinus rhythm in patients with valvular heart disease. 28 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant reduction of left and right atrial size and resection of both atrial auricles in Shahid Madani cardiothoracic center from September 2004 to October 2008. The procedure for atrial fibrillation treatment was performed with cardiopulmonary bypass and after mitral valve replacement. There was one in-hospital death postoperatively because of respiratory failure, but no other complication till 6 months after the operation. Out of 28 patients, 23 were in sinus rhythm one week after the operation, one patient had junctional rhythm after the operation that restored to sinus rhythm and 4 patients had persistent atrial fibrillation. During the 12-month follow up, atrial fibrillation was corrected in 82.14%. Doppler echocardiography in these patients with sinus rhythm demonstrated good atrial contractility. This procedure on both atria is effective and less invasive than the original maze procedure to eliminate the atrial fibrillation, and can be performed in patients with valvular heart disease without increasing the risk of operation.

  9. Monkey Lipsmacking Develops Like the Human Speech Rhythm

    Science.gov (United States)

    Morrill, Ryan J.; Paukner, Annika; Ferrari, Pier F.; Ghazanfar, Asif A.

    2012-01-01

    Across all languages studied to date, audiovisual speech exhibits a consistent rhythmic structure. This rhythm is critical to speech perception. Some have suggested that the speech rhythm evolved "de novo" in humans. An alternative account--the one we explored here--is that the rhythm of speech evolved through the modification of rhythmic facial…

  10. Heart Failure

    Science.gov (United States)

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  11. EFFECTS OF CIRCADIAN RHYTHM ON BALANCE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Karagul Osman

    2017-09-01

    Full Text Available Introduction. The aim of the study was to examine the effect of circadian rhythm on dynamic balance performance and to determine the role of physical activity level, body temperature, chronotype, and gender in this possible effect. Material and

  12. Working night shifts affects surgeons' biological rhythm

    DEFF Research Database (Denmark)

    Amirian, Ilda; Andersen, Lærke T; Rosenberg, Jacob

    2015-01-01

    BACKGROUND: Chronic sleep deprivation combined with work during the night is known to affect performance and compromise residents' own safety. The aim of this study was to examine markers of circadian rhythm and the sleep-wake cycle in surgeons working night shifts. METHODS: Surgeons were monitor...

  13. Egg-laying rhythm in Drosophila melanogaster

    Indian Academy of Sciences (India)

    2008-12-31

    Dec 31, 2008 ... production of oocytes to egg-laying on selected sites (Alle- mand 1976b; Yang et al. .... (vii) Is the egg-laying rhythm regulated by hormones? .... were shown to be induced by factors synthesized in the re- productive tract of the ...

  14. [Features of daily rhythm of arterial pressure in patients with primary arterial hypertension and neurogenic syncope conditions].

    Science.gov (United States)

    Musaeva, Z A; Oknin, V Iu; Khapaev, B A; Fedotova, A V; Veĭn, A M

    2002-01-01

    A comparative analysis of parameters of systemic BP in patients with primary arterial hypotension (PAH) and in patients with neurogenic syncopes (NS) in the cycle sleep-awake. Blood pressure was investigated in 20 patients with PAH aged 16-44 years and 18 patients with NS aged 16-49 years. 24-h ambulatory monitoring of BP was made on the monitor ABPM-02/M (Meditech, Hungary). Rhythm indices of BP in NS patients corresponded to age normal criteria. 24-h arrhythmia of BP in PAH patients manifests with excessive drop of diastolic BP in sleep (55% patients were overdippers). PAH and NS patients differ maximally by hypotonic load in sleep: 1.0 +/- 0.7% in NS vs 15.4 +/- 3.2% in PAH. Hypotonia episodes in awake PAH patients were registered at each 4th-5th measurement of BP, in NS patients--at each 11th-13th. Heart rate in awake PAH patients is higher than in healthy subjects. Hypotonic load in sleep carries the highest differentially-diagnostic importance. This makes more perspective examinations of such patients in the cycle sleep-awake. The changes observed in PAH patients evidence for activation of cerebral sympathico-adrenal systems participating in baroreflex regulation.

  15. RNAi of the circadian clock gene period disrupts the circadian rhythm but not the circatidal rhythm in the mangrove cricket

    OpenAIRE

    Takekata, Hiroki; Matsuura, Yu; Goto, Shin G.; Satoh, Aya; Numata, Hideharu

    2012-01-01

    The clock mechanism for circatidal rhythm has long been controversial, and its molecular basis is completely unknown. The mangrove cricket, Apteronemobius asahinai, shows two rhythms simultaneously in its locomotor activity: a circatidal rhythm producing active and inactive phases as well as a circadian rhythm modifying the activity intensity of circatidal active phases. The role of the clock gene period (per), one of the key components of the circadian clock in insects, was investigated in t...

  16. Demonstration of a day-night rhythm in human skeletal muscle oxidative capacity.

    Science.gov (United States)

    van Moorsel, Dirk; Hansen, Jan; Havekes, Bas; Scheer, Frank A J L; Jörgensen, Johanna A; Hoeks, Joris; Schrauwen-Hinderling, Vera B; Duez, Helene; Lefebvre, Philippe; Schaper, Nicolaas C; Hesselink, Matthijs K C; Staels, Bart; Schrauwen, Patrick

    2016-08-01

    A disturbed day-night rhythm is associated with metabolic perturbations that can lead to obesity and type 2 diabetes mellitus (T2DM). In skeletal muscle, a reduced oxidative capacity is also associated with the development of T2DM. However, whether oxidative capacity in skeletal muscle displays a day-night rhythm in humans has so far not been investigated. Lean, healthy subjects were enrolled in a standardized living protocol with regular meals, physical activity and sleep to reflect our everyday lifestyle. Mitochondrial oxidative capacity was examined in skeletal muscle biopsies taken at five time points within a 24-hour period. Core-body temperature was lower during the early night, confirming a normal day-night rhythm. Skeletal muscle oxidative capacity demonstrated a robust day-night rhythm, with a significant time effect in ADP-stimulated respiration (state 3 MO, state 3 MOG and state 3 MOGS, p < 0.05). Respiration was lowest at 1 PM and highest at 11 PM (state 3 MOGS: 80.6 ± 4.0 vs. 95.8 ± 4.7 pmol/mg/s). Interestingly, the fluctuation in mitochondrial function was also observed in whole-body energy expenditure, with peak energy expenditure at 11 PM and lowest energy expenditure at 4 AM (p < 0.001). In addition, we demonstrate rhythmicity in mRNA expression of molecular clock genes in human skeletal muscle. Our results suggest that the biological clock drives robust rhythms in human skeletal muscle oxidative metabolism. It is tempting to speculate that disruption of these rhythms contribute to the deterioration of metabolic health associated with circadian misalignment.

  17. Evaluation of circadian phenotypes utilizing fibroblasts from patients with circadian rhythm sleep disorders.

    Science.gov (United States)

    Hida, A; Ohsawa, Y; Kitamura, S; Nakazaki, K; Ayabe, N; Motomura, Y; Matsui, K; Kobayashi, M; Usui, A; Inoue, Y; Kusanagi, H; Kamei, Y; Mishima, K

    2017-04-25

    We evaluated the circadian phenotypes of patients with delayed sleep-wake phase disorder (DSWPD) and non-24-hour sleep-wake rhythm disorder (N24SWD), two different circadian rhythm sleep disorders (CRSDs) by measuring clock gene expression rhythms in fibroblast cells derived from individual patients. Bmal1-luciferase (Bmal1-luc) expression rhythms were measured in the primary fibroblast cells derived from skin biopsy samples of patients with DSWPD and N24SWD, as well as control subjects. The period length of the Bmal1-luc rhythm (in vitro period) was distributed normally and was 22.80±0.47 (mean±s.d.) h in control-derived fibroblasts. The in vitro periods in DSWPD-derived fibroblasts and N24SWD-derived fibroblasts were 22.67±0.67 h and 23.18±0.70 h, respectively. The N24SWD group showed a significantly longer in vitro period than did the control or DSWPD group. Furthermore, in vitro period was associated with response to chronotherapy in the N24SWD group. Longer in vitro periods were observed in the non-responders (mean±s.d.: 23.59±0.89 h) compared with the responders (mean±s.d.: 22.97±0.47 h) in the N24SWD group. Our results indicate that prolonged circadian periods contribute to the onset and poor treatment outcome of N24SWD. In vitro rhythm assays could be useful for predicting circadian phenotypes and clinical prognosis in patients with CRSDs.

  18. Non-24-Hour Sleep–Wake Rhythm Disorder in the Totally Blind: Diagnosis and Management

    Directory of Open Access Journals (Sweden)

    Maria Antonia Quera Salva

    2017-12-01

    Full Text Available Several aspects of human physiology and behavior are dominated by 24-h circadian rhythms with key impacts on health and well-being. These include mainly the sleep–wake cycle, vigilance and performance patterns, and some hormone secretions. The rhythms are generated spontaneously by an internal “pacemaker,” the suprachiasmatic nuclei within the anterior hypothalamus. This master clock has, for most humans, an intrinsic rhythm slightly longer than 24 h. Daily retinal light exposure is necessary for the synchronization of the circadian rhythms with the external 24-h solar environment. This daily synchronization process generally poses no problems for sighted individuals except in the context of jetlag or working night shifts being conditions of circadian desynchrony. However, many blind subjects with no light perception had periodical circadian desynchrony, in the absence of light information to the master clock leading to poor circadian rhythm synchronization. Affected patients experience cyclical or periodic episodes of poor sleep and daytime dysfunction, severely interfering with social, academic, and professional life. The diagnosis of Non-24 Sleep–Wake Rhythm Disorder, also named free-running disorder, non-entrained disorder, or hypernycthemeral syndrome, remains challenging from a clinical point of view due to the cyclical symptoms and should be confirmed by measurements of circadian biomarkers such as urinary melatonin to demonstrate a circadian period outside the normal range. Management includes behavioral modification and melatonin. Tasimelteon, a novel melatonin receptor 1 and 2 agonist, has demonstrated its effectiveness and safety with an evening dose of 20 mg and is currently the only treatment approved by the FDA and the European Medicines Agency.

  19. Biologic rhythms derived from Siberian mammoths' hairs.

    Directory of Open Access Journals (Sweden)

    Mike Spilde

    Full Text Available Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was ∼31 cms/year and ∼16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios, which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  20. Relation of N-Terminal Pro-B-Type Natriuretic Peptide and Left Ventricular Diastolic Function to Exercise Tolerance in Patients With Significant Valvular Heart Disease and Normal Left Ventricular Systolic Function.

    Science.gov (United States)

    Hwang, Ji-Won; Park, Sung-Ji; Cho, Eun Jeong; Kim, Eun Kyoung; Lee, Ga Yeon; Chang, Sung-A; Choi, Jin-Oh; Lee, Sang-Chol; Park, Seung Woo

    2017-06-01

    An association between N-terminal prohormone brain natriuretic peptide (NT-proBNP) and exercise tolerance in patients with valvular heart disease (VHD) has been suggested; however, there are few data available regarding this relation. The aim of this study is to evaluate the correlation between exercise tolerance and NT-proBNP in patients with asymptomatic or mildly symptomatic significant VHD and normal left ventricular ejection fraction (LV EF). A total of 96 patients with asymptomatic or mildly symptomatic VHD and normal LV EF (≥50%) underwent cardiopulmonary exercise echocardiography. NT-proBNP levels were determined at baseline and after exercise in 3 hours. Patients were divided in 2 groups based on lower (left atrial volume index before exercise, right ventricular systolic pressure before exercise, E velocity after exercise, and E/e' ratio after exercise varied significantly. In addition, peak VO 2 was inversely related to NT-proBNP before (r = -0.352, p left atrial volume index, E/e' ratio, and right ventricular systolic pressure before and after exercise. NT-proBNP after exercise was also directly related to the same parameters. NT-proBNP levels both before and after exercise were higher in the group with lower exercise tolerance. In conclusion, through the correlation among exercise tolerance, NT-proBNP, and parameters of diastolic dysfunction, we demonstrated that diastolic dysfunction and NT-proBNP could predict exercise tolerance in patients with significant VHD and normal LV EF. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Human autonomic rhythms: vagal cardiac mechanisms in tetraplegic subjects

    Science.gov (United States)

    Koh, J.; Brown, T. E.; Beightol, L. A.; Ha, C. Y.; Eckberg, D. L.

    1994-01-01

    1. We studied eight young men (age range: 20-37 years) with chronic, clinically complete high cervical spinal cord injuries and ten age-matched healthy men to determine how interruption of connections between the central nervous system and spinal sympathetic motoneurones affects autonomic cardiovascular control. 2. Baseline diastolic pressures and R-R intervals (heart periods) were similar in the two groups. Slopes of R-R interval responses to brief neck pressure changes were significantly lower in tetraplegic than in healthy subjects, but slopes of R-R interval responses to steady-state arterial pressure reductions and increases were comparable. Plasma noradrenaline levels did not change significantly during steady-state arterial pressure reductions in tetraplegic patients, but rose sharply in healthy subjects. The range of arterial pressure and R-R interval responses to vasoactive drugs (nitroprusside and phenylephrine) was significantly greater in tetraplegic than healthy subjects. 3. Resting R-R interval spectral power at respiratory and low frequencies was similar in the two groups. During infusions of vasoactive drugs, low-frequency R-R interval spectral power was directly proportional to arterial pressure in tetraplegic patients, but was unrelated to arterial pressure in healthy subjects. Vagolytic doses of atropine nearly abolished both low- and respiratory-frequency R-R interval spectral power in both groups. 4. Our conclusions are as follows. First, since tetraplegic patients have significant levels of low-frequency arterial pressure and R-R interval spectral power, human Mayer arterial pressure waves may result from mechanisms that do not involve stimulation of spinal sympathetic motoneurones by brainstem neurones. Second, since in tetraplegic patients, low-frequency R-R interval spectral power is proportional to arterial pressure, it is likely to be mediated by a baroreflex mechanism. Third, since low-frequency R-R interval rhythms were nearly abolished

  2. Redundancy of stomatal control for the circadian photosynthetic rhythm in Kalanchoë daigremontiana Hamet et Perrier.

    Science.gov (United States)

    Wyka, T P; Duarte, H M; Lüttge, U E

    2005-03-01

    In continuous light, the Crassulacean acid metabolism plant Kalanchoe daigremontiana Hamet et Perrier has a circadian rhythm of gas exchange with peaks occurring during the subjective night. The rhythm of gas exchange is coupled to a weak, reverse phased rhythm of quantum yield of photosystem II (Phi (PSII)). To test if the rhythm of Phi (PSII) persists in the absence of stomatal control, leaves were coated with a thin layer of translucent silicone grease which prevented CO2 and H2O exchange. In spite of this treatment, the rhythm of Phi (PSII) occurred with close to normal phase timing and with a much larger amplitude than in uncoated leaves. The mechanism underlying the Phi (PSII) rhythm in coated leaves can be explained by a circadian activity of phosphoenolpyruvate carboxylase (PEPC). At peaks of PEPC activity, the small amount of CO2 contained in the coated leaf could have become depleted, preventing the carboxylase activity of Rubisco and causing decreases in electron transport rates (observed as deep troughs of Phi (PSII) at 23-h in LL and at ca. 24-h intervals afterwards). Peaks of Phi (PSII) would be caused by a downregulation of PEPC leading to improved supply of CO2 to Rubisco. Substrate limitation of photochemistry at 23 h (trough of Phi (PSII)) was also suggested by the weak response of ETR in coated leaves to stepwise light enhancement. These results show that photosynthetic rhythmicity in K. daigremontiana is independent of stomatal regulation and may originate in the mesophyll.

  3. Wheel running improves REM sleep and attenuates stress-induced flattening of diurnal rhythms in F344 rats.

    Science.gov (United States)

    Thompson, Robert S; Roller, Rachel; Greenwood, Benjamin N; Fleshner, Monika

    2016-05-01

    Regular physical activity produces resistance to the negative health consequences of stressor exposure. One way that exercise may confer stress resistance is by reducing the impact of stress on diurnal rhythms and sleep; disruptions of which contribute to stress-related disease including mood disorders. Given the link between diurnal rhythm disruptions and stress-related disorders and that exercise both promotes stress resistance and is a powerful non-photic biological entrainment cue, we tested if wheel running could reduce stress-induced disruptions of sleep/wake behavior and diurnal rhythms. Adult, male F344 rats with or without access to running wheels were instrumented for biotelemetric recording of diurnal rhythms of locomotor activity, heart rate, core body temperature (CBT), and sleep (i.e. REM, NREM, and WAKE) in the presence of a 12 h light/dark cycle. Following 6 weeks of sedentary or exercise conditions, rats were exposed to an acute stressor known to disrupt diurnal rhythms and produce behaviors associated with mood disorders. Prior to stressor exposure, exercise rats had higher CBT, more locomotor activity during the dark cycle, and greater %REM during the light cycle relative to sedentary rats. NREM and REM sleep were consolidated immediately following peak running to a greater extent in exercise, compared to sedentary rats. In response to stressor exposure, exercise rats expressed higher stress-induced hyperthermia than sedentary rats. Stressor exposure disrupted diurnal rhythms in sedentary rats; and wheel running reduced these effects. Improvements in sleep and reduced diurnal rhythm disruptions following stress could contribute to the health promoting and stress protective effects of exercise.

  4. Cardiorespiratory Coupling: Common Rhythms in Cardiac, Sympathetic, and Respiratory Activities

    Science.gov (United States)

    Dick, Thomas E.; Hsieh, Yee-Hsee; Dhingra, Rishi R.; Baekey, David M.; Galán, Roberto F.; Wehrwein, Erica; Morris, Kendall F.

    2014-01-01

    Cardiorespiratory coupling is an encompassing term describing more than the well-recognized influences of respiration on heart rate and blood pressure. Our data indicate that cardiorespiratory coupling reflects a reciprocal interaction between autonomic and respiratory control systems, and the cardiovascular system modulates the ventilatory pattern as well. For example, cardioventilatory coupling refers to the influence of heart beats and arterial pulse pressure on respiration and is the tendency for the next inspiration to start at a preferred latency after the last heart beat in expiration. Multiple complementary, well-described mechanisms mediate respiration’s influence on cardiovascular function, whereas mechanisms mediating the cardiovascular system’s influence on respiration may only be through the baroreceptors but are just being identified. Our review will describe a differential effect of conditioning rats with either chronic intermittent or sustained hypoxia on sympathetic nerve activity but also on ventilatory pattern variability. Both intermittent and sustained hypoxia increase sympathetic nerve activity after 2 weeks but affect sympatho-respiratory coupling differentially. Intermittent hypoxia enhances sympatho-respiratory coupling, which is associated with low variability in the ventilatory pattern. In contrast, after constant hypobaric hypoxia, 1-to-1 coupling between bursts of sympathetic and phrenic nerve activity is replaced by 2-to-3 coupling. This change in coupling pattern is associated with increased variability of the ventilatory pattern. After baro-denervating hypobaric hypoxic-conditioned rats, splanchnic sympathetic nerve activity becomes tonic (distinct bursts are absent) with decreases during phrenic nerve bursts and ventilatory pattern becomes regular. Thus, conditioning rats to either intermittent or sustained hypoxia accentuates the reciprocal nature of cardiorespiratory coupling. Finally, identifying a compelling physiologic

  5. Impact of pulmonary arterial hypertension and its therapy on indices of heart rate variability.

    Science.gov (United States)

    Can, Mehmet Mustafa; Kaymaz, Cihangir; Pochi, Nartilla; Aktimur, Tugba

    2013-08-01

    To compare heart rate variability (HRV) indices between pulmonary arterial hypertension (PAH) patients and controls, and to investigate whether therapy improves heart rhythm. Thirty-eight patients and 20 controls underwent Holter monitoring. HRV was analyzed before and after PAH therapy. Various time, and frequency domain indices of HRV analysis including standard deviation of all normal-to-normal intervals, standard deviation of mean values for all normal-to-normal intervals over 5 min, and square root of the mean square differences of successive RR intervals were recorded and analyzed before and after 1 year of PAH therapy. Significant differences with regard to diminished physical capacity, impared cardiac output, increased BNP in PAH cohort; HRV indices were diminished compared to controls and no differences between before and after PAH therapy with respect to analysis of HRV. Patients exhibited depressed HRV and therapy failed to improve HRV indices suggesting urgent unmet need for better therapeutic options. Patients with PAH exhibit severely depressed HRV. Surprisingly, PAH specific therapy for 1 year with phosphodiesterase- 5 inhibitor, prostacyclin analogue, endhotelin receptor antagonist, or their combination failed to improve HRV indices suggesting urgent unmet need for better therapeutic options.

  6. Taser X26 discharges in swine: ventricular rhythm capture is dependent on discharge vector.

    Science.gov (United States)

    Valentino, Daniel J; Walter, Robert J; Dennis, Andrew J; Margeta, Bosko; Starr, Frederic; Nagy, Kimberly K; Bokhari, Faran; Wiley, Dorion E; Joseph, Kimberly T; Roberts, Roxanne R

    2008-12-01

    Data from our previous studies indicate that Taser X26 stun devices can acutely alter cardiac function in swine. We hypothesized that most transcardiac discharge vectors would capture ventricular rhythm, but that other vectors, not traversing the heart, would fail to capture the ventricular rhythm. Using an Institutional Animal Care and Use Committee (IACUC) approved protocol, four Yorkshire pigs (25-36 kg) were anesthetized, paralyzed with succinylcholine (2 mg/kg), and then exposed to 10 second discharges from a police-issue Taser X26. For most discharges, the barbed darts were pushed manually into the skin to their full depth (12 mm) and were arranged in either transcardiac (such that a straight line connecting the darts would cross the region of the heart) or non-transcardiac vectors. A total of 11 different vectors and 22 discharge conditions were studied. For each vector, by simply rotating the cartridge 180-degrees in the gun, the primary current-emitting dart was changed and the direction of current flow during the discharge was reversed without physically moving the darts. Echocardiography and electrocardiograms (ECGs) were performed before, during, and after all discharges. p values captured immediately in 52.5% (31 of 59) of the discharges on the ventral surface of the animal. In each of these cases, capture of the ventricular rhythm with rapid ventricular contractions consistent with ventricular tachycardia (VT) or flutter was seen throughout the discharge. A total of 27 discharges were administered with transcardiac vectors and ventricular capture occurred in 23 of these discharges (85.2% capture rate). A total of 32 non-transcardiac discharges were administered ventrally and capture was seen in only eight of these (25% capture rate). Ventricular fibrillation (VF) was seen with two vectors, both of which were transcardiac. In the remaining animals, VT occurred postdischarge until sinus rhythm was regained spontaneously. For most transcardiac vectors

  7. Circadian Rhythm Disturbances in Patients with Alzheimer's Disease: A Review

    Directory of Open Access Journals (Sweden)

    Dawit A. Weldemichael

    2010-01-01

    Full Text Available Circadian Rhythm Disturbances (CRDs affect as many as a quarter of Alzheimer's disease (AD patients during some stage of their illness. Alterations in the suprachiasmatic nucleus and melatonin secretion are the major factors linked with the cause of CRDs. As a result, the normal physiology of sleep, the biological clock, and core body temperature are affected. This paper systematically discusses some of the causative factors, typical symptoms, and treatment options for CRDs in patients with AD. This paper also emphasizes the implementation of behavioral and environmental therapies before embarking on medications to treat CRDs. Pharmacotherapeutic options are summarized to provide symptomatic benefits for the patient and relieve stress on their families and professional care providers. As of today, there are few studies relative to CRDs in AD. Large randomized trials are warranted to evaluate the effects of treatments such as bright light therapy and engaging activities in the reduction of CRDs in AD patients.

  8. Circadian rhythms in sports performance--an update.

    Science.gov (United States)

    Drust, B; Waterhouse, J; Atkinson, G; Edwards, B; Reilly, T

    2005-01-01

    We discuss current knowledge on the description, impact, and underlying causes of circadian rhythmicity in sports performance. We argue that there is a wealth of information from both applied and experimental work, which, when considered together, suggests that sports performance is affected by time of day in normal entrained conditions and that the variation has at least some input from endogenous mechanisms. Nevertheless, precise information on the relative importance of endogenous and exogenous factors is lacking. No single study can answer both the applied and basic research questions that are relevant to this topic, but an appropriate mixture of real-world research on rhythm disturbances and tightly controlled experiments involving forced desynchronization protocols is needed. Important issues, which should be considered by any chronobiologist interested in sports and exercise, include how representative the study sample and the selected performance tests are, test-retest reliability, as well as overall design of the experiment.

  9. Pediatric cardiology. Clinical and practical experiences with heart diseases of children, juveniles and young adults; Kinderkardiologie. Klinik und Praxis der Herzerkrankungen bei Kindern, Jugendlichen und jungen Erwachsenen

    Energy Technology Data Exchange (ETDEWEB)

    Haas, Nikolaus A. [Herz- und Diabeteszentrum NRW, Bad Oeynhausen (Germany). Klinik fuer angeborene Herzfehler; Kleideiter, Ulrich [Klinik fuer Kinder- und Jugendmedizin, Coesfeld (Germany)

    2011-07-01

    The book on pediatric cardiology covers the following chapters: (I) Fundamentals and diagnostics: pediatric cardiologic anamnesis, electrocardiograms, thorax X-radiography, MRT and CT of the heart, nuclear medical diagnostics, exercise tests, heart catheter examination, electrophysiological tests. (II) Leading symptoms: Cyanosis, cardiac murmur, thorax pain, palpitation, syncopes. (III) Disease pictures: congenital heart defects, acquired heart defects, cardiomyopathies, heart rhythm disturbances, heart insufficiency, arterial hypertension, pulmonary hypertension, other heart involving syndromes. (IV) Therapy: Catheter interventional therapy, post-surgical pediatric cardiac therapy, surgery involving the life-support machine, mechanical cardiovascular support systems, initial treatment of newborns with critical heart defects, heart transplantation, vaccination of children with heart diseases, medicinal therapy.

  10. [Interpersonal and social rhythm therapy (IPSRT)].

    Science.gov (United States)

    Bottai, T; Biloa-Tang, M; Christophe, S; Dupuy, C; Jacquesy, L; Kochman, F; Meynard, J-A; Papeta, D; Rahioui, H; Adida, M; Fakra, E; Kaladjian, A; Pringuey, D; Azorin, J-M

    2010-12-01

    Bipolar disorder is common, recurrent, often severe and debiliting disorder. All types of bipolar disorder have a common determinant: depressive episode. It is justify to propose a psychotherapy which shown efficacy in depression. Howewer, perturbations in circadian rhythms have been implicated in the genesis of each episode of the illness. Biological circadian dysregulation can be encouraged by alteration of time-givers (Zeitgebers) or occurrence of time-disturbers (Zeitstörers). Addition of social rhythm therapy to interpersonal psychotherapy leads to create a new psychotherapy adaptated to bipolar disorders: InterPersonal and Social Rhythm Therapy (IPSRT). IPSRT, in combinaison with medication, has demonstrated efficacy as a treatment for bipolar disorders. IPSRT combines psychoeducation, behavioral strategy to regularize daily routines and interpersonal psychotherapy which help patients cope better with the multiple psychosocial and relationship problems associated with this chronic disorder. The main issues of this psychotherapy are: to take the history of the patient's illness and review of medication, to help patient for "grief for the lost healthy self" translated in the french version in "acceptance of a long-term medical condition", to give the sick role, to examinate the current relationships and changes proximal to the emergence of mood symptoms in the four problem areas (unresolved grief, interpersonal disputes, role transitions, role déficits), to examinate and increase daily routines and social rhythms. French version of IPSRT called TIPARS (with few differences), a time-limited psychotherapy, in 24 sessions during approximatively 6 months, is conducted in three phases. In the initial phase, the therapist takes a thorough history of previous episodes and their interpersonal context and a review of previous medication, provides psychoeducation, evaluates social rhythms, introduces the Social Rhythm Metric, identifies the patient's main interpersonal

  11. Heart rate turbulence as a marker of myocardial electrical instability in children with hypertrophic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    V. A. Makarova

    2014-01-01

    Full Text Available Heart rate turbulence is a myocardial electrical instability marker used to stratify the risk of sudden cardiac death. Fifty children aged 7 to 17 years with hypertrophic cardiomyopathy were examined. The survey program included standard electrocardiography, Doppler echocardiography, and 24-hour Holter ECG monitoring. Heart rate turbulence parameters, such as turbulence onset and turbulence slope, were analyzed. According to turbulence onset greater than zero, heart rate turbulence impairment was identified in 5 of the 24 patients included in the survey. The abnormal turbulence slope values of less than 6 msec/RR were found in 3 patients. Both parameters were abnormal in 1 patient. Heart rate turbulence impairment was significantly more common in children with the non-obstructive form of hypertrophic cardiomyopathy than in those with its obstructive form (χ2=3,05; p=0,08. All the children with abnormal heart rhythm turbulence values had one or more major risk factors for sudden cardiac death, which significantly exceeds their rates in the normal heart rate turbulence groups (χ2=7,11; p=0,007. The patients with abnormal turbulence onset values were more often found to have syncope (χ2=3,2; p=0,02. One such patient was recorded to have unstable ventricular tachycardia (χ2=10,56; p=0,001. Our findings suggest that heart rate turbulence is an additional predictor of the unfavorable course of hypertrophic cardiomyopathy in children. 

  12. Bidirectional Cardio-Respiratory Interactions in Heart Failure

    Directory of Open Access Journals (Sweden)

    Nikola N. Radovanović

    2018-03-01

    Full Text Available We investigated cardio-respiratory coupling in patients with heart failure by quantification of bidirectional interactions between cardiac (RR intervals and respiratory signals with complementary measures of time series analysis. Heart failure patients were divided into three groups of twenty, age and gender matched, subjects: with sinus rhythm (HF-Sin, with sinus rhythm and ventricular extrasystoles (HF-VES, and with permanent atrial fibrillation (HF-AF. We included patients with indication for implantation of implantable cardioverter defibrillator or cardiac resynchronization therapy device. ECG and respiratory signals were simultaneously acquired during 20 min in supine position at spontaneous breathing frequency in 20 healthy control subjects and in patients before device implantation. We used coherence, Granger causality and cross-sample entropy analysis as complementary measures of bidirectional interactions between RR intervals and respiratory rhythm. In heart failure patients with arrhythmias (HF-VES and HF-AF there is no coherence between signals (p < 0.01, while in HF-Sin it is reduced (p < 0.05, compared with control subjects. In all heart failure groups causality between signals is diminished, but with significantly stronger causality of RR signal in respiratory signal in HF-VES. Cross-sample entropy analysis revealed the strongest synchrony between respiratory and RR signal in HF-VES group. Beside respiratory sinus arrhythmia there is another type of cardio-respiratory interaction based on the synchrony between cardiac and respiratory rhythm. Both of them are altered in heart failure patients. Respiratory sinus arrhythmia is reduced in HF-Sin patients and vanished in heart failure patients with arrhythmias. Contrary, in HF-Sin and HF-VES groups, synchrony increased, probably as consequence of some dominant neural compensatory mechanisms. The coupling of cardiac and respiratory rhythm in heart failure patients varies depending on the

  13. Combined heart-kidney transplantation after total artificial heart insertion.

    Science.gov (United States)

    Ruzza, A; Czer, L S C; Ihnken, K A; Sasevich, M; Trento, A; Ramzy, D; Esmailian, F; Moriguchi, J; Kobashigawa, J; Arabia, F

    2015-01-01

    We present the first single-center report of 2 consecutive cases of combined heart and kidney transplantation after insertion of a total artificial heart (TAH). Both patients had advanced heart failure and developed dialysis-dependent renal failure after implantation of the TAH. The 2 patients underwent successful heart and kidney transplantation, with restoration of normal heart and kidney function. On the basis of this limited experience, we consider TAH a safe and feasible option for bridging carefully selected patients with heart and kidney failure to combined heart and kidney transplantation. Recent FDA approval of the Freedom driver may allow outpatient management at substantial cost savings. The TAH, by virtue of its capability of providing pulsatile flow at 6 to 10 L/min, may be the mechanical circulatory support device most likely to recover patients with marginal renal function and advanced heart failure. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Sleep, circadian rhythms, and athletic performance.

    Science.gov (United States)

    Thun, Eirunn; Bjorvatn, Bjørn; Flo, Elisabeth; Harris, Anette; Pallesen, Ståle

    2015-10-01

    Sleep deprivation and time of day are both known to influence performance. A growing body of research has focused on how sleep and circadian rhythms impact athletic performance. This review provides a systematic overview of this research. We searched three different databases for articles on these issues and inspected relevant reference lists. In all, 113 articles met our inclusion criteria. The most robust result is that athletic performance seems to be best in the evening around the time when the core body temperature typically is at its peak. Sleep deprivation was negatively associated with performance whereas sleep extension seems to improve performance. The effects of desynchronization of circadian rhythms depend on the local time at which performance occurs. The review includes a discussion of differences regarding types of skills involved as well as methodological issues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Regulation of reproduction by the circadian rhythms.

    Science.gov (United States)

    Zhang, Wen-Xiang; Chen, Si-Yu; Liu, Chang

    2016-12-25

    Mammals synchronize their circadian activity primarily to the cycles of light and darkness in the environment. Circadian rhythm is controlled by the central clock in the hypothalamic suprachiasmatic nucleus (SCN) and the peripheral clocks in various tissues. More importantly, the central clock can integrate photic/nonphotic signals to generate rhythmic outputs, and then drive the slave oscillators in peripheral tissues through neuroendocrine and behavioral signals. Human reproductive activities, as some other physiological functions, are controlled by the biological clocks. Accumulating lines of epidemiological and genetic evidence indicate that disruption of circadian clock can be directly involved in multiple pathological processes, including infertility. In this review, we mainly discuss the presence of a circadian clock in reproductive tissues and its roles in follicles development, ovulation, spermatogenesis, fertilization and embryo implantation, etc. As the increased shift work and assisted reproductive technologies possibly disrupt circadian rhythmicity to impact reproduction, the importance of circadian rhythms should be highlighted in the regulation of reproductive process.

  16. Circadian rhythms and obesity in mammals.

    Science.gov (United States)

    Froy, Oren

    2012-01-01

    Obesity has become a serious public health problem and a major risk factor for the development of illnesses, such as insulin resistance and hypertension. Attempts to understand the causes of obesity and develop new therapeutic strategies have mostly focused on caloric intake and energy expenditure. Recent studies have shown that the circadian clock controls energy homeostasis by regulating the circadian expression and/or activity of enzymes, hormones, and transport systems involved in metabolism. Moreover, disruption of circadian rhythms leads to obesity and metabolic disorders. Therefore, it is plausible that resetting of the circadian clock can be used as a new approach to attenuate obesity. Feeding regimens, such as restricted feeding (RF), calorie restriction (CR), and intermittent fasting (IF), provide a time cue and reset the circadian clock and lead to better health. In contrast, high-fat (HF) diet leads to disrupted circadian expression of metabolic factors and obesity. This paper focuses on circadian rhythms and their link to obesity.

  17. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to vitamin K2 and contribution to the normal function of the heart and blood vessels (ID 125, further assessment) pursuant to Article 13(1) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Tetens, Inge

    Following a request from the European Commission, pursuant to Article 13 of Regulation (EC) No 1924/2006, the Panel on Dietetic Products, Nutrition and Allergies was asked to provide a scientific opinion on a health claim related to vitamin K2 and contribution to the normal function of the heart...... and blood vessels. The food constituent that is the subject of the claim, vitamin K2, is sufficiently characterised. The claimed effect, contribution to the normal function of the heart and blood vessels, is a beneficial physiological effect. The proposed target population is the general population......, that the results of two prospective cohort studies are in conflict regarding the risk of coronary heart disease associated with vitamin K2 intakes, that high intakes of vitamin K2 were associated with a significantly lower degree of aortic calcification in one prospective cohort study after adjustment...

  18. Heart Failure Association of the European Society of Cardiology Specialist Heart Failure Curriculum

    DEFF Research Database (Denmark)

    McDonagh, Theresa A; Gardner, Roy S; Lainscak, Mitja

    2014-01-01

    Training Curricula. In addition, European Society of Cardiology (ESC) subspecialty curricula exist for Interventional Cardiology and Heart Rhythm Management. The purpose of this heart failure curriculum is to provide a framework which can be used as a blueprint for training across Europe. This blueprint...... mirrors other ESC curricula. Each section has three components: the knowledge required, the skills which are necessary, and the professionalism (attitudes and behaviours) which should be attained. The programme is designed to last 2 years. The first year is devoted to the specialist heart failure module...

  19. Circadian rhythms of women with fibromyalgia

    Science.gov (United States)

    Klerman, E. B.; Goldenberg, D. L.; Brown, E. N.; Maliszewski, A. M.; Adler, G. K.

    2001-01-01

    Fibromyalgia syndrome is a chronic and debilitating disorder characterized by widespread nonarticular musculoskeletal pain whose etiology is unknown. Many of the symptoms of this syndrome, including difficulty sleeping, fatigue, malaise, myalgias, gastrointestinal complaints, and decreased cognitive function, are similar to those observed in individuals whose circadian pacemaker is abnormally aligned with their sleep-wake schedule or with local environmental time. Abnormalities in melatonin and cortisol, two hormones whose secretion is strongly influenced by the circadian pacemaker, have been reported in women with fibromyalgia. We studied the circadian rhythms of 10 women with fibromyalgia and 12 control healthy women. The protocol controlled factors known to affect markers of the circadian system, including light levels, posture, sleep-wake state, meals, and activity. The timing of the events in the protocol were calculated relative to the habitual sleep-wake schedule of each individual subject. Under these conditions, we found no significant difference between the women with fibromyalgia and control women in the circadian amplitude or phase of rhythms of melatonin, cortisol, and core body temperature. The average circadian phases expressed in hours posthabitual bedtime for women with and without fibromyalgia were 3:43 +/- 0:19 and 3:46 +/- 0:13, respectively, for melatonin; 10:13 +/- 0:23 and 10:32 +/- 0:20, respectively for cortisol; and 5:19 +/- 0:19 and 4:57 +/- 0:33, respectively, for core body temperature phases. Both groups of women had similar circadian rhythms in self-reported alertness. Although pain and stiffness were significantly increased in women with fibromyalgia compared with healthy women, there were no circadian rhythms in either parameter. We suggest that abnormalities in circadian rhythmicity are not a primary cause of fibromyalgia or its symptoms.

  20. Heart Diseases

    Science.gov (United States)

    ... you're like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the ... of disability. There are many different forms of heart disease. The most common cause of heart disease ...

  1. Heart Transplantation

    Science.gov (United States)

    A heart transplant removes a damaged or diseased heart and replaces it with a healthy one. The healthy heart comes from a donor who has died. It is the last resort for people with heart failure when all other treatments have failed. The ...

  2. NEUROTICISM PROFILE IN CORONARY HEART DISEASE

    OpenAIRE

    Bhargava, S. C.; Sharma, S. N.; Agarwal, B. V.

    1980-01-01

    SUMMARY Thirty seven cases of coronary heart disease and 30 normal healthy controls were administered Hindi version of MHQ. The coronary heart disease patients scored significantly higher on total neuroticism, free-floating anxiety and somatic anxiety subscales of MHQ.

  3. Circadian rhythms in handwriting kinematics and legibility.

    Science.gov (United States)

    Jasper, Isabelle; Gordijn, Marijke; Häussler, Andreas; Hermsdörfer, Joachim

    2011-08-01

    The aim of the present study was to analyze the circadian rhythmicity in handwriting kinematics and legibility and to compare the performance between Dutch and German writers. Two subject groups underwent a 40 h sleep deprivation protocol under Constant Routine conditions either in Groningen (10 Dutch subjects) or in Berlin (9 German subjects). Both groups wrote every 3h a test sentence of similar structure in their native language. Kinematic handwriting performance was assessed with a digitizing tablet and evaluated by writing speed, writing fluency, and script size. Writing speed (frequency of strokes and average velocity) revealed a clear circadian rhythm, with a parallel decline during night and a minimum around 3:00 h in the morning for both groups. Script size and movement fluency did not vary with time of day in neither group. Legibility of handwriting was evaluated by intra-individually ranking handwriting specimens of the 13 sessions by 10 German and 10 Dutch raters. Whereas legibility ratings of the German handwriting specimens deteriorated during night in parallel with slower writing speed, legibility of the Dutch handwriting deteriorated not until the next morning. In conclusion, the circadian rhythm of handwriting kinematics seems to be independent of script language at least among the two tested western countries. Moreover, handwriting legibility is also subject to a circadian rhythm which, however, seems to be influenced by variations in the assessment protocol. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Cardiac support device (ASD) delivers bone marrow stem cells repetitively to epicardium has promising curative effects in advanced heart failure.

    Science.gov (United States)

    Yue, Shizhong; Naveed, Muhammad; Gang, Wang; Chen, Dingding; Wang, Zhijie; Yu, Feng; Zhou, Xiaohui

    2018-05-12

    Ventricular restraint therapy is a non-transplant surgical option for the management of advanced heart failure (HF). To augment the therapeutic applications, it is hypothesized that ASD shows remarkable capabilities not only in delivering stem cells but also in dilated ventricles. Male SD rats were divided into four groups (n = 6): normal, HF, HF + ASD, and HF + ASD-BMSCs respectively. HF was developed by left anterior descending (LAD) coronary artery ligation in all groups except normal group. Post-infarcted electrocardiography (ECG) and brain natriuretic peptide (BNP) showed abnormal heart function in all model groups and HF + ASD-BMSCs group showed significant improvement as compared to other HF, HF + ASD groups on day 30. Masson's trichrome staining was used to study the histology, and a large blue fibrotic area has been observed in HF and HF + ASD groups and quantification of fibrosis was assessed. ASD-treated rats showed normal heart rhythm, demonstrated by smooth -ST and asymmetrical T-wave. The mechanical function of the heart such as left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP) and heart rate was brought to normal when treated with ASD-BMSCs. This effect was more prominent than that of ASD therapy alone. In comparison to HF group, the SD rats in HF + ASD-BMBCs group showed a significant decline in BNP levels. So ASD can deliver BMSCs to the cardiomyocytes successfully and broaden the therapeutic efficacy, in comparison to the restraint device alone. An effective methodology to manage the end-stage HF has been proved.

  5. Heart rate variability alters cardiac repolarization and electromechanical dynamics.

    Science.gov (United States)

    Phadumdeo, Vrishti M; Weinberg, Seth H

    2018-04-07

    Heart rate continuously varies due to autonomic regulation, stochasticity in pacemaking, and circadian rhythm, collectively termed heart rate variability (HRV), during normal physiological conditions. Low HRV is clinically associated with an elevated risk of cardiac arrhythmias. Alternans, a beat-to-beat alternation in action potential duration (APD) and/or intracellular calcium (Ca) transient, is a well-known risk factor associated with cardiac arrhythmias that is typically studied under conditions of a constant pacing rate, i.e., the absence of HRV. In this study, we investigate the effects of HRV on the interplay between APD, Ca, and electromechanical properties, employing a nonlinear discrete-time map model that governs APD and intracellular Ca cycling with a stochastic pacing period. We find that HRV can decrease variation in APD and peak Ca at fast pacing rates for which alternans is present. Further, increased HRV typically disrupts the alternating pattern for both APD and peak Ca and weakens the correlation between APD and peak Ca, thus decoupling Ca-mediated instabilities from repolarization alternation. We find that the efficacy of these effects is regulated by the sarcoplasmic reticulum Ca uptake rate. Overall, these results demonstrate that HRV disrupts arrhythmogenic alternans and suggests that HRV may be a significant factor in preventing life-threatening arrhythmias. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Basic Principles of Interpersonal Social Rhythm Therapy in Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Gokben Hizli Sayar

    2014-08-01

    Full Text Available Interpersonal Social Rhythm Therapy is a psychotherapy modality that helps the patient recognize the relationship between disruptions in social rhythms and the onset of previous episodes of psychiatric disorders. It uses psychoeducation and behavioral techniques to maintain social rhythm and sleep/wake regularity. It is closely related to and ldquo;social zeitgeber theory and rdquo; that emphasizes the importance that social rhythm regularity may play in synchronization of circadian rhythms in individuals with or at risk for bipolar spectrum disorders. Interpersonal and social rhythm therapy have been shown to stabilize social rhythms and enhance course and outcome in bipolar disorder. This review focuses on the theoretical principles and the basic steps of interpersonal and social rhythm therapy as a psychotherapy approach in bipolar disorder. PubMed, Scopus, Google Scholar databases were searched without temporal restriction. Search terms included interpersonal social rhythm therapy, bipolar, mood disorders. Abstracts were reviewed for relevance, and randomized controlled trials of interpersonal and social rhythm therapy in bipolar disorder selected. These researches also summarized on the final part of this review. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 438-446

  7. Biologic Rhythms Derived from Siberian Mammoths Hairs

    Energy Technology Data Exchange (ETDEWEB)

    M Spilde; A Lanzirotti; C Qualls; G Phillips; A Ali; L Agenbroad; O Appenzeller

    2011-12-31

    Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was {approx}31 cms/year and {approx}16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  8. Effect of single intraoperative dose of amiodarone in patients with rheumatic valvular heart disease and atrial fibrillation undergoing valve replacement surgery

    Directory of Open Access Journals (Sweden)

    Selvaraj Thiruvenkadam

    2009-01-01

    Full Text Available Maintenance of sinus rhythm (SR is superior to rate control in atrial fibrillation (AF. In order to achieve SR, we administered single-dose intravenous amiodarone intraoperatively and evaluated its effect on conversion of rheumatic AF to SR in patients undergoing valvular heart surgery. Patients were randomly assigned to amiodarone ( n = 42 or control ( n = 40 group in a double blind manner. The amiodarone group received amiodarone (3 mg/kg intravenously prior to the institution of cardiopulmonary bypass and the control group received the same volume of normal saline. In the amiodarone group, the initial rhythm after the release of aortic cross clamp was noted to be AF in 14.3% ( n = 6 and remained so in 9.5% ( n = 4 of patients till the end of surgery. In the control group, the rhythm soon after the release of aortic cross clamp was AF in 37.5% ( n = 15 ( p = 0.035 and remained so in 32.5% ( n = 13 of patients till the end of surgery ( p = 0.01. At the end of first post-operative day 21.4% ( n = 9 of patients in amiodarone group and 55% ( n = 22 of patients in control group were in AF ( p = 0.002. The requirement of cardioversion/defibrillation was 1.5 (±0.54 in amiodarone group and 2.26 (±0.73 in the control group ( p = 0.014, and the energy needed was 22.5 (±8.86 joules in the amiodarone group and 40.53 (±16.5 in the control group ( p = 0.008. A single intraoperative dose of intravenous amiodarone increased the conversion rate of AF to normal sinus rhythm, reduced the need and energy required for cardioversion/defibrillation and reduced the recurrence of AF within one day.

  9. Bidirectional Cardio-Respiratory Interactions in Heart Failure.

    Science.gov (United States)

    Radovanović, Nikola N; Pavlović, Siniša U; Milašinović, Goran; Kirćanski, Bratislav; Platiša, Mirjana M

    2018-01-01

    We investigated cardio-respiratory coupling in patients with heart failure by quantification of bidirectional interactions between cardiac (RR intervals) and respiratory signals with complementary measures of time series analysis. Heart failure patients were divided into three groups of twenty, age and gender matched, subjects: with sinus rhythm (HF-Sin), with sinus rhythm and ventricular extrasystoles (HF-VES), and with permanent atrial fibrillation (HF-AF). We included patients with indication for implantation of implantable cardioverter defibrillator or cardiac resynchronization therapy device. ECG and respiratory signals were simultaneously acquired during 20 min in supine position at spontaneous breathing frequency in 20 healthy control subjects and in patients before device implantation. We used coherence, Granger causality and cross-sample entropy analysis as complementary measures of bidirectional interactions between RR intervals and respiratory rhythm. In heart failure patients with arrhythmias (HF-VES and HF-AF) there is no coherence between signals ( p respiratory signal in HF-VES. Cross-sample entropy analysis revealed the strongest synchrony between respiratory and RR signal in HF-VES group. Beside respiratory sinus arrhythmia there is another type of cardio-respiratory interaction based on the synchrony between cardiac and respiratory rhythm. Both of them are altered in heart failure patients. Respiratory sinus arrhythmia is reduced in HF-Sin patients and vanished in heart failure patients with arrhythmias. Contrary, in HF-Sin and HF-VES groups, synchrony increased, probably as consequence of some dominant neural compensatory mechanisms. The coupling of cardiac and respiratory rhythm in heart failure patients varies depending on the presence of atrial/ventricular arrhythmias and it could be revealed by complementary methods of time series analysis.

  10. A Heart too Drunk to Drive; AV Block following Acute Alcohol Intoxication.

    Science.gov (United States)

    van Stigt, Arthur H; Overduin, Ruben J; Staats, Liza C; Loen, Vera; van der Heyden, Marcel A G

    2016-02-29

    Acute excessive alcohol consumption is associated with heart rhythm disorders like atrial fibrillation but also premature ventricular contractions, collectively known as the "holiday heart syndrome". More rarely but clinically significant are reports of atrioventricular (AV) conduction disturbances in binge drinkers with no underlying heart disease or chronic alcohol consumption. To obtain better insights into common denominators and the potential underlying mechanisms we collected and compared individual case reports of AV block following acute alcohol intoxication in otherwise healthy people. By screening PubMed, Google Scholar, Scopus and JSTOR, fifteen cases were found of which eight were sufficiently documented for full analysis. Blood alcohol levels ranged from 90 to 958 mg/dl (19 to 205 mM). Second and third degree AV block was observed most (6/8) albeit that in two of these patients a vagal stimulus led to deterioration from first into higher order AV block. In all cases, patients reverted to normal sinus rhythm upon becoming sober again. Mildly lowered body temperature (35.9 ± 0.5°C) was observed but can be excluded as a major cause of conduction blockade. We hypothesize that ethanol induced partial inhibition of calcium and potentially also sodium currents in conductive tissue structures may be one of the mechanisms of conduction slowing and block that may become exaggerated upon increased vagal tone. An impairment of gap junction function cannot be excluded as a contributing factor. In conclusion, cases of documented alcohol induced AV block are very rare but events can occur at relatively low serum alcohol levels which should prompt to awareness of this phenomenon in alcohol intoxicated patients.

  11. Scapulohumeral rhythm in shoulders with reverse shoulder arthroplasty.

    Science.gov (United States)

    Walker, David; Matsuki, Keisuke; Struk, Aimee M; Wright, Thomas W; Banks, Scott A

    2015-07-01

    Little is known about kinematic function of reverse total shoulder arthroplasty (RTSA). Scapulohumeral rhythm (SHR) is a common metric for assessing muscle function and shoulder joint motion. The purpose of this study was to compare SHR in shoulders with RTSA to normal shoulders. Twenty-eight subjects, more than 12 months after unilateral RTSA, were recruited for an Institutional Review Board-approved study. Subjects performed arm abduction in the coronal plane with and without a 1.4-kg hand-held weight. Three-dimensional model-image registration techniques were used to measure orientation and position for the humerus and scapula from fluoroscopic images. Analysis of variance and Tukey tests were used to assess groupwise and pairwise differences. SHR in RTSA shoulders (1.3:1) was significantly lower than in normal shoulders (3:1). Below 30° abduction, RTSA and normal shoulders show a wide range of SHR (1.3:1 to 17:1). Above 30° abduction, SHR in RTSA shoulders was 1.3:1 for unweighted abduction and 1.3:1 for weighted abduction. Maximum RTSA shoulder abduction in weighted trials was lower than in unweighted trials. SHR variability in RTSA shoulders decreased with increasing arm elevation. RTSA shoulders show kinematics that are significantly different from normal shoulders. SHR in RTSA shoulders was significantly lower than in normal shoulders, indicating that RTSA shoulders use more scapulothoracic motion and less glenohumeral motion to elevate the arm. With these observations, it may be possible to improve rehabilitation protocols, with particular attention to the periscapular muscles, and implant design or placement to optimize functional outcomes in shoulders with RTSA. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  12. Circadian rhythms of GIP and GLP1 in glucose-tolerant and in type 2 diabetic patients after biliopancreatic diversion

    DEFF Research Database (Denmark)

    Mingrone, G; Nolfe, G; Gissey, G Castagneto

    2009-01-01

    AIMS/HYPOTHESIS: We tested the hypothesis that the reversibility of insulin resistance and diabetes observed after biliopancreatic diversion (BPD) is related to changes in circadian rhythms of gastrointestinal hormones. METHODS: Ten morbidly obese participants, five with normal glucose tolerance......(-1)). CONCLUSIONS/INTERPRETATION: An incretin circadian rhythm was shown for the first time in morbid obesity. The effect of BPD on the 24 h pattern of incretin differed between NGT and diabetic patients. GLP1 secretion impairment was reversed in NGT and could not be overcome by surgery in diabetes...

  13. EFSA NDA Panel (EFSA Panel on Dietetic Products, Nutrition and Allergies), 2014. Scientific Opinion on the substantiation of a health claim related to “Lactobacillus plantarum TENSIA® in the semi-hard Edam-type „heart cheese‟ of Harmony™” and maintenance of normal blood pressure pursuant to Article

    DEFF Research Database (Denmark)

    Tetens, Inge

    on the scientific substantiation of a health claim related to “Lactobacillus plantarum TENSIA® in the semi-hard Edam-type “heart cheese” of Harmony™” and maintenance of normal blood pressure (BP). The food constituent L. plantarum TENSIA®, which is the subject of the health claim, is sufficiently characterised...... exert the claimed effect. The Panel concludes that a cause and effect relationship has not been established between the consumption of Lactobacillus plantarum TENSIA®in the semi-hard Edam-type “heart cheese” of Harmony™ and maintenance of normal blood pressure........ The Panel considers that the maintenance of normal blood pressure is a beneficial physiological effect. The applicant provided 47 references which did not address the effects of L. plantarum TENSIA® on BP. The Panel considers that no conclusions can be drawn from these references for the scientific...

  14. The impact of non-dipper circadian rhythm of blood pressure on left ventricular hypertrophy in patients with non-dialysis chronic kidney disease.

    Science.gov (United States)

    Che, Xiajing; Mou, Shan; Zhang, Weiming; Zhang, Minfang; Gu, Leyi; Yan, Yucheng; Ying, Hua; Hu, Chunhua; Qian, Jiaqi; Ni, Zhaohui

    2017-04-01

    Objective The aim of this study was to investigate the correlation between non-dipper circadian rhythm of blood pressure (BP) and left ventricular hypertrophy (LVH) in patients with chronic kidney disease (CKD). Methods and results All 257 patients with stage 1 to 5 CKD were enrolled in the study and classified into a CKD1-3 group and a CKD4-5 group according to renal function. The parameters and circadian rhythm of BP were measured by a GE Marquette Tonoport V Eng dynamic sphygmomanometer, and cardiac structure was examined by echocardiography. The incidence of abnormal circadian BP rhythm (non-dipper rhythm) was quite high (75.4% in all enrolled patients and 71.3% in the patients with normal BP levels) in CKD patients and increased with the deterioration of renal function. Changes of cardiac structure such as LVH in patients with non-dipper BP were more distinct than in patients with dipper BP. The development of left ventricular mass index (LVMI) correlated positively with the incidence of non-dipper BP rhythm. Multiple regression analysis showed that 24-h systolic BP (β = 0.417, P circadian rhythm of blood pressure was quite high in CKD patients and increased with the deterioration of renal function. Non-dipper circadian rhythm of BP is closely related with LVMI.

  15. Sensorimotor rhythm neurofeedback as adjunct therapy for Parkinson's disease.

    Science.gov (United States)

    Philippens, Ingrid H C H M; Wubben, Jacqueline A; Vanwersch, Raymond A P; Estevao, Dave L; Tass, Peter A

    2017-08-01

    Neurofeedback may enhance compensatory brain mechanisms. EEG-based sensorimotor rhythm neurofeedback training was suggested to be beneficial in Parkinson's disease. In a placebo-controlled study in parkinsonian nonhuman primates we here show that sensorimotor rhythm neurofeedback training reduces MPTP-induced parkinsonian symptoms and both ON and OFF scores during classical L-DOPA treatment. Our findings encourage further development of sensorimotor rhythm neurofeedback training as adjunct therapy for Parkinson's disease which might help reduce L-DOPA-induced side effects.

  16. Holiday heart syndrome: a case report | Garba | Nigerian Journal of ...

    African Journals Online (AJOL)

    Alcohol is known to have both beneficial and detrimental effects on the cardiovascular system. An association has been found between alcohol use and rhythm disturbances, especially binge drinking that may occur on holidays and weekends. Not much literature can be found on the prevalence of Holiday Heart Syndrome ...

  17. Clarifying Normalization

    Science.gov (United States)

    Carpenter, Donald A.

    2008-01-01

    Confusion exists among database textbooks as to the goal of normalization as well as to which normal form a designer should aspire. This article discusses such discrepancies with the intention of simplifying normalization for both teacher and student. This author's industry and classroom experiences indicate such simplification yields quicker…

  18. iPhone 4s photoplethysmography: which light color yields the most accurate heart rate and normalized pulse volume using the iPhysioMeter Application in the presence of motion artifact?

    Directory of Open Access Journals (Sweden)

    Kenta Matsumura

    Full Text Available Recent progress in information and communication technologies has made it possible to measure heart rate (HR and normalized pulse volume (NPV, which are important physiological indices, using only a smartphone. This has been achieved with reflection mode photoplethysmography (PPG, by using a smartphone's embedded flash as a light source and the camera as a light sensor. Despite its widespread use, the method of PPG is susceptible to motion artifacts as physical displacements influence photon propagation phenomena and, thereby, the effective optical path length. Further, it is known that the wavelength of light used for PPG influences the photon penetration depth and we therefore hypothesized that influences of motion artifact could be wavelength-dependant. To test this hypothesis, we made measurements in 12 healthy volunteers of HR and NPV derived from reflection mode plethysmograms recorded simultaneously at three different spectral regions (red, green and blue at the same physical location with a smartphone. We then assessed the accuracy of the HR and NPV measurements under the influence of motion artifacts. The analyses revealed that the accuracy of HR was acceptably high with all three wavelengths (all rs > 0.996, fixed biases: -0.12 to 0.10 beats per minute, proportional biases: r =  -0.29 to 0.03, but that of NPV was the best with green light (r = 0.791, fixed biases: -0.01 arbitrary units, proportional bias: r = 0.11. Moreover, the signal-to-noise ratio obtained with green and blue light PPG was higher than that of red light PPG. These findings suggest that green is the most suitable color for measuring HR and NPV from the reflection mode photoplethysmogram under motion artifact conditions. We conclude that the use of green light PPG could be of particular benefit in ambulatory monitoring where motion artifacts are a significant issue.

  19. Systematic analysis of ECG predictors of sinus rhythm maintenance after electrical cardioversion for persistent atrial fibrillation.

    Science.gov (United States)

    Lankveld, Theo; de Vos, Cees B; Limantoro, Ione; Zeemering, Stef; Dudink, Elton; Crijns, Harry J; Schotten, Ulrich

    2016-05-01

    Electrical cardioversion (ECV) is one of the rhythm control strategies in patients with persistent atrial fibrillation (AF). Unfortunately, recurrences of AF are common after ECV, which significantly limits the practical benefit of this treatment in patients with AF. The objectives of this study were to identify noninvasive complexity or frequency parameters obtained from the surface electrocardiogram (ECG) to predict sinus rhythm (SR) maintenance after ECV and to compare these ECG parameters with clinical predictors. We studied a wide variety of ECG-derived time- and frequency-domain AF complexity parameters in a prospective cohort of 502 patients with persistent AF referred for ECV. During 1-year follow-up, 161 patients (32%) maintained SR. The best clinical predictor of SR maintenance was antiarrhythmic drug (AAD) treatment. A model including clinical parameters predicted SR maintenance with a mean cross-validated area under the receiver operating characteristic curve (AUC) of 0.62 ± 0.05. The best single ECG parameter was the dominant frequency (DF) on lead V6. Combining several ECG parameters predicted SR maintenance with a mean AUC of 0.64 ± 0.06. Combining clinical and ECG parameters improved prediction to a mean AUC of 0.67 ± 0.05. Although the DF was affected by AAD treatment, excluding patients taking AADs did not significantly lower the predictive performance captured by the ECG. ECG-derived parameters predict SR maintenance during 1-year follow-up after ECV at least as good as known clinical predictors of rhythm outcome. The DF proved to be the most powerful ECG-derived predictor. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  20. Keeping the Rhythm : Cardiac Pacemaker Cell Development

    NARCIS (Netherlands)

    Burkhard, S.B.

    2017-01-01

    The heart is the first organ to form and function in the developing vertebrate embryo. Its proper morphogenesis and function is crucial for survival. Here we focus on the development and characterization of a highly specialized subset of cardiac cells, the pacemaker cells. In the mammalian heart,

  1. The impact of circadian rhythms on medical imaging and radiotherapy regimes for the paediatric patient

    International Nuclear Information System (INIS)

    Forssell-Aronsson, E.; Quinlan, R.A.

    2017-01-01

    Daily rhythmic changes are found in cellular events in cell cycle, DNA repair, apoptosis and angiogenesis in both normal and tumour tissue, as well as in enzymatic activity and drug metabolism. In this paper, we hypothesize that circadian rhythms need to be considered in radiation protection and optimization in personalized medicine, especially for paediatric care. The sensitivity of the eye lens to ionizing radiation makes the case for limiting damage to the lens epithelium by planning medical radio-imaging procedures for the afternoon, rather than the morning. Equally, the tumour and normal tissue response to radiotherapy is also subject to diurnal variation enabling optimization of time of treatment. (authors)

  2. suPAR level is associated with myocardial impairment assessed with advanced echocardiography in patients with type 1 diabetes with normal ejection fraction and without known heart disease or end-stage renal disease

    DEFF Research Database (Denmark)

    Theilade, Simone; Rossing, Peter; Eugen-Olsen, Jesper

    2016-01-01

    AIM: Heart disease is a common fatal diabetes-related complication. Early detection of patients at particular risk of heart disease is of prime importance. Soluble urokinase plasminogen activator receptor (suPAR) is a novel biomarker for development of cardiovascular disease. We investigate if su...

  3. P wave detector with PP rhythm tracking: evaluation in different arrhythmia contexts

    International Nuclear Information System (INIS)

    Portet, François

    2008-01-01

    Automatic detection of atrial activity (P waves) in an electrocardiogram (ECG) is a crucial task to diagnose the presence of arrhythmias. The P wave is difficult to detect and most of the approaches in the literature have been evaluated on normal sinus rhythms and rarely considered arrhythmia contexts other than atrial flutter and fibrillation. A novel knowledge-based P wave detector algorithm is presented. It is self-adaptive to the patient and able to deal with certain arrhythmias by tracking the PP rhythm. The detector has been tested on 12 records of the MIT-BIH arrhythmia database containing several ventricular and supra-ventricular arrhythmias. On the overall records, the detector demonstrates Se = 96.60% and Pr = 95.46%; for the normal sinus rhythm, it reaches Se = 97.76% and Pr = 96.80% and, in the case of Mobitz type II, it demonstrates Se = 72.79% and Pr = 99.51%. It also shows good performance for trigeminy and bigeminy, and outperforms some more sophisticated techniques. Although the results emphasize the difficulty of P wave detection in difficult arrhythmias (supra and ventricular tachycardias), it shows that domain knowledge can efficiently support signal processing techniques

  4. Standing down Straight: Jump Rhythm Technique's Rhythm-Driven, Community-Directed Approach to Dance Education

    Science.gov (United States)

    Siegenfeld, Billy

    2009-01-01

    "Standing down straight" means to stand on two feet with both stability and relaxation. Using standing down straight as the foundation of class work, Jump Rhythm Technique offers a fresh alternative to conventional systems of dance study. It bases its pedagogy on three behaviors: grounding the body so that it can move with power and efficiency,…

  5. Heart Truth

    Science.gov (United States)

    ... health! Get a free badge or banner to post to your website or blog. Are you at risk for heart disease? Here's how to find out . Planning to use The Heart Truth logo? Check out our logo guidelines and downloads. ...

  6. Heart Disease

    Science.gov (United States)

    ... it may be caused by diseases, such as connective tissue disorders, excessive iron buildup in your body (hemochromatosis), the buildup of abnormal proteins (amyloidosis) or by some cancer treatments. Causes of heart infection A heart infection, ...

  7. Heart Attack

    Science.gov (United States)

    ... family history of heart attack race – African Americans, Mexican Americans, Native Americans, and native Hawaiians are at ... Your doctor will prescribe the medicines that are right for you. If you have had a heart ...

  8. Environmental factors contributed to circannual rhythm of semen quality.

    Science.gov (United States)

    Mao, Huan; Feng, Lei; Yang, Wan-Xi

    2017-01-01

    We investigated whether human semen parameters present circannual rhythm or not, and whether environmental factors exert on semen quality. This retrospective study used data of patients mainly from Reproductive Medicine Center and Urology and Andrology Clinic of a general hospital in China. Sperm concentration and motility were measured by computer aided sperm analysis (CASA). Sperm morphology was scored based on the strict criteria (WHO, 2010). The Kruskal-Wallis rank test was used to investigate the relationship between semen parameters and season/month. Partial correlation coefficients were used to analyze the relationship between semen parameters and environmental factors. In this study, we found that sperm concentration and total amount per ejaculate were significantly lower in summer and higher in winter. But, sperm progressive motility and motility were significantly higher in spring and summer (from March to June), lower in autumn and winter (September and October). Unexpectedly, normal sperm morphology and mixed agglutination reaction (MAR) positive rate didn't vary along with season or month. Furthermore, temperature was negatively related to sperm concentration and total amount per ejaculate. Precipitation was positively associated with progressive motility and normal sperm morphology, but negatively related to sperm head defect percentage. The length of sunlight was positively related to progressive motility. The Air Quality Index (AQI) was positively associated with semen volume and sperm total amount per ejaculate. These suggest seasonal and monthly variation underlying some semen parameters.

  9. Heart pacemaker

    Science.gov (United States)

    Cardiac pacemaker implantation; Artificial pacemaker; Permanent pacemaker; Internal pacemaker; Cardiac resynchronization therapy; CRT; Biventricular pacemaker; Arrhythmia - pacemaker; Abnormal heart ...

  10. Diabetes, Dyslipidemia, and Heart Protection

    Science.gov (United States)

    Fact Sheet Diabetes, Dyslipidemia, and Heart Protection What is dyslipidemia? Cholesterol and triglycerides, known as lipids, are fatty substances that the body normally produces. Dyslipidemia means that lipid levels ...

  11. Effects of damage to the suprachiasmatic area of the anterior hypothalamus on the daily melatonin and cortisol rhythms in the rhesus monkey

    Energy Technology Data Exchange (ETDEWEB)

    Reppert, S.M.; Perlow, M.J.; Ungerleider, L.G.; Mishkin, M.; Tamarkin, L.; Orloff, D.G.; Hoffman, H.J.; Klein, D.C.

    1981-12-01

    The effects of lesions of the suprachiasmatic nucleus (SCN) on the circadian rhythms in melatonin and cortisol were examined in the rhesus monkey. The concentrations of the two hormones were monitored in cerebrospinal fluid (CSF) withdrawn from two sham-operated animals, two animals with complete bilateral SCN lesions, and two animals with partial SCN damage at 4 and 8 months after surgery. In the sham-operated animals, as in the intact animal, the daily melatonin rhythm was entrained to the daily light-dark cycle, was suppressed in constant light, and persisted in constant darkness. In contrast, neither animal with complete SCN ablation exhibited a daily pattern of CSF melatonin in diurnal lighting at 4 months after surgery nor were their melatonin levels at constant low values. Furthermore, CSF melatonin concentrations were not suppressed in either animal by constant light. Surprisingly, at 8 months after surgery, spectral analysis revealed a 24-hr component to the melatonin patterns for each animal with complete SCN ablation in both diurnal lighting and constant darkness. The two animals with partial SCN damage exhibited a daily melatonin rhythm in diurnal lighting, but constant light did not suppress CSF melatonin concentrations consistently. Daily rhythms persisted in both for a 6 1/2-d period of study in constant darkness. In contrast to the alterations in the melatonin rhythm after SCN damage, there was no apparent effect of either partial or complete SCN ablation on the daily CSF cortisol rhythm. These data indicate that, in the rhesus monkey, the SCN is important for the generation, photic entrainment, and photic suppression of the melatonin rhythm. However, circadian oscillators located outside of the SCN region may control the normal daily cortisol rhythm and perhaps the melatonin rhythm in the absence of the SCN.

  12. Effects of damage to the suprachiasmatic area of the anterior hypothalamus on the daily melatonin and cortisol rhythms in the rhesus monkey

    International Nuclear Information System (INIS)

    Reppert, S.M.; Perlow, M.J.; Ungerleider, L.G.; Mishkin, M.; Tamarkin, L.; Orloff, D.G.; Hoffman, H.J.; Klein, D.C.

    1981-01-01

    The effects of lesions of the suprachiasmatic nucleus (SCN) on the circadian rhythms in melatonin and cortisol were examined in the rhesus monkey. The concentrations of the two hormones were monitored in cerebrospinal fluid (CSF) withdrawn from two sham-operated animals, two animals with complete bilateral SCN lesions, and two animals with partial SCN damage at 4 and 8 months after surgery. In the sham-operated animals, as in the intact animal, the daily melatonin rhythm was entrained to the daily light-dark cycle, was suppressed in constant light, and persisted in constant darkness. In contrast, neither animal with complete SCN ablation exhibited a daily pattern of CSF melatonin in diurnal lighting at 4 months after surgery nor were their melatonin levels at constant low values. Furthermore, CSF melatonin concentrations were not suppressed in either animal by constant light. Surprisingly, at 8 months after surgery, spectral analysis revealed a 24-hr component to the melatonin patterns for each animal with complete SCN ablation in both diurnal lighting and constant darkness. The two animals with partial SCN damage exhibited a daily melatonin rhythm in diurnal lighting, but constant light did not suppress CSF melatonin concentrations consistently. Daily rhythms persisted in both for a 6 1/2-d period of study in constant darkness. In contrast to the alterations in the melatonin rhythm after SCN damage, there was no apparent effect of either partial or complete SCN ablation on the daily CSF cortisol rhythm. These data indicate that, in the rhesus monkey, the SCN is important for the generation, photic entrainment, and photic suppression of the melatonin rhythm. However, circadian oscillators located outside of the SCN region may control the normal daily cortisol rhythm and perhaps the melatonin rhythm in the absence of the SCN

  13. Atrial Fibrillation Following Surgical Management of Ischemic Heart Disease; One Year, Single Center, Single Surgeon Results

    Directory of Open Access Journals (Sweden)

    Ahmet Barış Durukan

    2012-08-01

    Full Text Available Introduction: Postoperative atrial fibrillation is the most common arrhythmia following bypasssurgery with significant morbidity, mortality and increased healthcare costs. The aim of this studyis to determine the incidence and timing of atrial fibrillation, identify the risk factors coveringpreoperative and intraoperative periods, evaluate rate of return to sinus rhythm by disharge, andexplore the impact on postoperative outcomes in a large group of patients operated in a singlecenter by a single surgeon.Patients and Methods: Between January 2011 and January 2012, 418 patients on preoperativesinus rhythm were operated for ischemic heart disease and associated complications (left ventricleaneurysm repair and ischemic mitral insufficiency in a single center, by a single surgeon.The preoperative, intraoperative and postoperative variables were studied.Results: The mean age of the patients were 61.92 ± 10.05, and 77.5% were male. Atrial fibrillationdeveloped in 68 (16.3% patients. The incidence peaked at second day. Patients with atrialfibrillation were older (p< 0.001. Gender, preoperative comorbidities, ejection fraction, left atrialdiameter, preoperative beta-blocker use, leukocyte count, type of operation and intraoperativevariables did not affect its occurence. Intensive care unit and hospital length of stay were longer(p< 0.05. 95.5% (n= 65 of patients were in normal sinus rhythm at discharge.Conclusion: Postoperative atrial fibrillation is a popular subject with unknowns and controversialresults which may lead to wrong interpretations. We believe that every center has its own risk factors related with the population of that region. Discussion will last, but simple precautions and close monitoring will help to minimizeadverse outcomes.

  14. Travel and Heart Disease

    Science.gov (United States)

    ... a game park for the day,” Gandy said. Plane Precautions Sitting immobile on long plane flights can slightly increase a normal person’s risk ... Disease (PAD) • Stroke • Vascular Health • Venous Thromboembolism (VTE) • Consumer Healthcare • Tools For Your Heart Health • Watch, Learn & ...

  15. Effects of 9-hour time zone changes on fatigue and circadian rhythms of sleep/wake and core temperature

    Science.gov (United States)

    Gander, P. H.; Myhre, G.; Graeber, R. C.; Andersen, H. T.; Lauber, J. K.

    1985-01-01

    Physiological and psychological disruptions caused by transmeridian flights may affect the ability of flight crews to meet operational demands. To study these effects, 9 Royal Norwegian Airforces P3-Orion crewmembers flew from Norway to California (-9 hr), and back (+9 hr). Rectal temperature, heart rate and wrist activity were recorded every 2 min, fatigue and mood were rated every 2 hr during the waking day, and logs were kept of sleep times and ratings. Subjects also completed 4 personality inventories. The time-zone shifts produced negative changes in mood which persisted longer after westward flights. Sleep quality (subjective and objective) and duration were slightly disrupted (more after eastward flights). The circadian rhythms of sleep/wake and temperature both completed the 9-hr delay by day 5 in California, although temperature adjusted more slowly. The size of the delay shift was significantly correlated with scores on extraversion and achievement need personality scales. Response to the 9-hr advance were more variable. One subject exhibited a 15-hr delay in his temperature rhythm, and an atypical sleep/nap pattern. On average, the sleep/wake cycle (but not the temperature rhythm), completed the 9-hr advance by the end of the study. Both rhythms adapted more slowly after the eastward flight.

  16. Circadian rhythm and its role in malignancy

    Directory of Open Access Journals (Sweden)

    Mahmood Saqib

    2010-03-01

    Full Text Available Abstract Circadian rhythms are daily oscillations of multiple biological processes directed by endogenous clocks. The circadian timing system comprises peripheral oscillators located in most tissues of the body and a central pacemaker located in the suprachiasmatic nucleus (SCN of the hypothalamus. Circadian genes and the proteins produced by these genes constitute the molecular components of the circadian oscillator which form positive/negative feedback loops and generate circadian rhythms. The circadian regulation extends beyond clock genes to involve various clock-controlled genes (CCGs including various cell cycle genes. Aberrant expression of circadian clock genes could have important consequences on the transactivation of downstream targets that control the cell cycle and on the ability of cells to undergo apoptosis. This may lead to genomic instability and accelerated cellular proliferation potentially promoting carcinogenesis. Different lines of evidence in mice and humans suggest that cancer may be a circadian-related disorder. The genetic or functional disruption of the molecular circadian clock has been found in various cancers including breast, ovarian, endometrial, prostate and hematological cancers. The acquisition of current data in circadian clock mechanism may help chronotherapy, which takes into consideration the biological time to improve treatments by devising new therapeutic approaches for treating circadian-related disorders, especially cancer.

  17. Turn exchange rhythm in English dialogues

    Science.gov (United States)

    Fon, Janice

    2005-09-01

    This study looked at the relationship between rhythm and exchange type in British English, a stress-timed language, and Singaporean English, a syllable-timed language, using a spontaneous speech corpus. Exchange intervals (EIs), or the time difference between the end of one speaker and the beginning of another, were measured and exchanges of different types were labeled. Results showed that, in a dialogue, EIs were generally limited to a narrow range. However, within this range, EIs had at least four functions. First, EIs were reflective of the cognitive load and functioned as a way to differentiate various exchange types. Those requiring more cognitive resources, such as question-and-answer pairs, generally needed longer EIs than those not as cognitively loaded, such as backchanneling pairs. Second, EIs were indicative of linguistic rhythm. Singaporean English tended to have shorter EIs than British English. Third, EIs were reflective of politeness. The degree of politeness correlated negatively with EI. Shorter EIs showed a higher degree of respect. Finally, EIs were also indicative of the level of insecurity of a speaker, which was best reflected by gender differences. Females in general had longer EIs than males.

  18. Temperature compensation and entrainment in circadian rhythms

    International Nuclear Information System (INIS)

    Bodenstein, C; Heiland, I; Schuster, S

    2012-01-01

    To anticipate daily variations in the environment and coordinate biological activities into a daily cycle many organisms possess a circadian clock. In the absence of external time cues the circadian rhythm persists with a period of approximately 24 h. The clock phase can be shifted by single pulses of light, darkness, chemicals, or temperature and this allows entrainment of the clock to exactly 24 h by cycles of these zeitgebers. On the other hand, the period of the circadian rhythm is kept relatively constant within a physiological range of constant temperatures, which means that the oscillator is temperature compensated. The mechanisms behind temperature compensation and temperature entrainment are not fully understood, neither biochemically nor mathematically. Here, we theoretically investigate the interplay of temperature compensation and entrainment in general oscillatory systems. We first give an analytical treatment for small temperature shifts and derive that every temperature-compensated oscillator is entrainable to external small-amplitude temperature cycles. Temperature compensation ensures that this entrainment region is always centered at the endogenous period regardless of possible seasonal temperature differences. Moreover, for small temperature cycles the entrainment region of the oscillator is potentially larger for rectangular pulses. For large temperature shifts we numerically analyze different circadian clock models proposed in the literature with respect to these properties. We observe that for such large temperature shifts sinusoidal or gradual temperature cycles allow a larger entrainment region than rectangular cycles. (paper)

  19. Circadian Rhythms, Sleep Deprivation, and Human Performance

    Science.gov (United States)

    Goel, Namni; Basner, Mathias; Rao, Hengyi; Dinges, David F.

    2014-01-01

    Much of the current science on, and mathematical modeling of, dynamic changes in human performance within and between days is dominated by the two-process model of sleep–wake regulation, which posits a neurobiological drive for sleep that varies homeostatically (increasing as a saturating exponential during wakefulness and decreasing in a like manner during sleep), and a circadian process that neurobiologically modulates both the homeostatic drive for sleep and waking alertness and performance. Endogenous circadian rhythms in neurobehavioral functions, including physiological alertness and cognitive performance, have been demonstrated using special laboratory protocols that reveal the interaction of the biological clock with the sleep homeostatic drive. Individual differences in circadian rhythms and genetic and other components underlying such differences also influence waking neurobehavioral functions. Both acute total sleep deprivation and chronic sleep restriction increase homeostatic sleep drive and degrade waking neurobehavioral functions as reflected in sleepiness, attention, cognitive speed, and memory. Recent evidence indicating a high degree of stability in neurobehavioral responses to sleep loss suggests that these trait-like individual differences are phenotypic and likely involve genetic components, including circadian genes. Recent experiments have revealed both sleep homeostatic and circadian effects on brain metabolism and neural activation. Investigation of the neural and genetic mechanisms underlying the dynamically complex interaction between sleep homeostasis and circadian systems is beginning. A key goal of this work is to identify biomarkers that accurately predict human performance in situations in which the circadian and sleep homeostatic systems are perturbed. PMID:23899598

  20. Rhythms of EEG and cognitive processes

    Directory of Open Access Journals (Sweden)

    Novikova S.I.

    2015-06-01

    Full Text Available The study of cognitive processes is regarded to be more effective if it combines a psychological approach with a neurophysiological one. This approach makes it possible to come closer to understanding of the basic mechanisms of different cognitive processes, to describe the patterns of forming these mechanisms in ontogenesis, to investigate the origin of cognitive impairments, and to develop intervention techniques. The promising way of investigating the mechanisms of cognitive functions is the electroencephalography (EEG. This is a non-invasive, safe, and relatively cheap method of research of the functional condition of the brain. The characteristics of EEG rhythms, recorded with different cognitive loads, reflect the processes of functional modulation of neural network activity of the cortex, which serves the neurophysiologic basis for attention, memory and other cognitive processes. The article provides an overview of works containing the analysis of the alpha and theta rhythms’ dynamics in various states of wakefulness. It also introduces the substantiation of methodology of functional regulatory approach to the interpretation of behaviors of EEG rhythms.

  1. Metaiodobenzylguanidine and heart rate variability in heart failure

    International Nuclear Information System (INIS)

    Kurata, Chinori; Shouda, Sakae; Mikami, Tadashi; Uehara, Akihiko; Ishikawa, Keiko; Tawarahara, Kei; Nakano, Tomoyasu; Matoh, Fumitaka; Takeuchi, Kazuhiko

    1998-01-01

    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 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)

  2. 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)

  3. A circadian rhythm regulating hyphal melanization in Cercospora kikuchii.

    Science.gov (United States)

    Bluhm, Burton H; Burnham, A Michele; Dunkle, Larry D

    2010-01-01

    Many metabolic and developmental processes in fungi are controlled by biological rhythms. Circadian rhythms approximate a daily (24 h) cycle and have been thoroughly studied in the model fungus, Neurospora crassa. However relatively few examples of true circadian rhythms have been documented among other filamentous fungi. In this study we describe a circadian rhythm underlying hyphal melanization in Cercospora kikuchii, an important pathogen of soybean. After growth in light or light : dark cycles, colonies transferred to darkness produced zonate bands of melanized hyphae interspersed with bands of hyaline hyphae. Rhythmic production of bands was remarkably persistent in the absence of external cues, lasting at least 7 d after transfer to darkness, and was compensated over a range of temperatures. As in N. crassa, blue light but not red light was sufficient to entrain the circadian rhythm in C. kikuchii, and a putative ortholog of white collar-1, one of the genes required for light responses in N. crassa, was identified in C. kikuchii. Circadian regulation of melanization is conserved in other members of the genus: Similar rhythms were identified in another field isolate of C. kikuchii as well as field isolates of C. beticola and C. sorghi, but not in wild-type strains of C. zeae-maydis or C. zeina. This report represents the first documented circadian rhythm among Dothideomycete fungi and provides a new opportunity to dissect the molecular basis of circadian rhythms among filamentous fungi.

  4. Effects of Some Aspects of Rhythm on Tempo Perception.

    Science.gov (United States)

    Wang, Cecilia Chu

    1984-01-01

    Results indicated that significantly more time is needed to perceive tempo increase than tempo decrease, uneven rhythm then even rhythm, and melody alone than melody with accompaniment. Furthermore, significant interaction effects involving beat locations of tempo change suggest that differential groupings may be a factor in tempo discrimination.…

  5. Effects of tempo and timing of simple musical rhythms

    NARCIS (Netherlands)

    Repp, B.H.; Windsor, W.L.; Desain, P.W.M.

    2002-01-01

    In this study we investigated whether and how the timing of musical rhythms changes with tempo. Twelve skilled pianists played a monophonic 8-bar melody in 21 different rhythmic versions at 4 different tempi. Within bars, the rhythms represented all possible ordered pairs and triplets of note values

  6. A Circadian Rhythm Regulating Hyphal Melanization in Cercospora Kikuchii

    Science.gov (United States)

    Circadian rhythms, biochemical or developmental processes with a period length of approximately 24 hours, are thoroughly documented in plants and animals. However, virtually all of what is currently known about circadian rhythms in fungi is derived from the model fungus, Neurospora crassa, including...

  7. A novel animal model linking adiposity to altered circadian rhythms

    Science.gov (United States)

    Researchers have provided evidence for a link between obesity and altered circadian rhythms (e.g., shift work, disrupted sleep), but the mechanism for this association is still unknown. Adipocytes possess an intrinsic circadian clock, and circadian rhythms in adipocytokines and adipose tissue metab...

  8. Circadian Activity Rhythms, Time Urgency, and Achievement Concerns.

    Science.gov (United States)

    Watts, Barbara L.

    Many physiological and psychological processes fluctuate throughout the day in fairly stable, rhythmic patterns. The relationship between individual differences in circadian activity rhythms and a sense of time urgency were explored as well as a number of achievement-related variables. Undergraduates (N=308), whose circadian activity rhythms were…

  9. Interactive Rhythm Learning System by Combining Tablet Computers and Robots

    Directory of Open Access Journals (Sweden)

    Chien-Hsing Chou

    2017-03-01

    Full Text Available This study proposes a percussion learning device that combines tablet computers and robots. This device comprises two systems: a rhythm teaching system, in which users can compose and practice rhythms by using a tablet computer, and a robot performance system. First, teachers compose the rhythm training contents on the tablet computer. Then, the learners practice these percussion exercises by using the tablet computer and a small drum set. The teaching system provides a new and user-friendly score editing interface for composing a rhythm exercise. It also provides a rhythm rating function to facilitate percussion training for children and improve the stability of rhythmic beating. To encourage children to practice percussion exercises, a robotic performance system is used to interact with the children; this system can perform percussion exercises for students to listen to and then help them practice the exercise. This interaction enhances children’s interest and motivation to learn and practice rhythm exercises. The results of experimental course and field trials reveal that the proposed system not only increases students’ interest and efficiency in learning but also helps them in understanding musical rhythms through interaction and composing simple rhythms.

  10. Unexpected diversity in socially synchronized rhythms of shorebirds

    NARCIS (Netherlands)

    Bulla, Martin; Valcu, Mihai; Dokter, Adriaan M; Dondua, Alexei G; Kosztolányi, András; Helm, Barbara; Sandercock, Brett K; Casler, Bruce; Ens, Bruno J.; Spiegel, Caleb S; Hassell, Chris J; Küpper, Clemens; Minton, Clive; Burgas, Daniel; Lank, David B; Payer, David C; Loktionov, Egor Y; Nol, Erica; Kwon, Eunbi; Smith, Fletcher; Gates, H River; Vitnerová, Hana; Prüter, Hanna; Johnson, James A; St Clair, James J H; Lamarre, Jean-François; Rausch, Jennie; Reneerkens, Jeroen; Conklin, Jesse R; Burger, Joanna; Liebezeit, Joe; Bêty, Joël; Coleman, Jonathan T; Figuerola, Jordi; Hooijmeijer, Joslyn; Alves, José A; Smith, Joseph A M; Weidinger, Karel; Koivula, Kari; Gosbell, Ken; Exo, Klaus-Michael; Niles, Larry; Koloski, Laura; McKinnon, Laura; Praus, Libor; Klaassen, Marcel; Giroux, Marie-Andrée; Sládeček, Martin; Boldenow, Megan L; Goldstein, Michael I; Šálek, Miroslav; Senner, Nathan; Rönkä, Nelli; Lecomte, Nicolas; Gilg, Olivier; Vincze, Orsolya; Johnson, Oscar W; Smith, Paul A; Woodard, Paul F; Tomkovich, Pavel S; Battley, Phil F; Bentzen, Rebecca; Lanctot, Richard B; Porter, Ron; Saalfeld, Sarah T; Freeman, Scott; Brown, Stephen C; Yezerinac, Stephen; Székely, Tamás; Montalvo, Tomás; Piersma, Theunis; Loverti, Vanessa; Pakanen, Veli-Matti; Tijsen, Wim; Kempenaers, Bart

    2016-01-01

    The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities

  11. The evolution of rhythm cognition: Timing in music and speech

    NARCIS (Netherlands)

    Ravignani, A.; Honing, H.; Kotz, S.A.

    This editorial serves a number of purposes. First, it aims at summarizing and discussing 33 accepted contributions to the special issue ‘The evolution of rhythm cognition: Timing in music and speech’. The major focus of the issue is the cognitive neuroscience of rhythm, intended as a neurobehavioral

  12. Interaction with Mass Media: The Importance of Rhythm and Tempo.

    Science.gov (United States)

    Snow, Robert P.

    1987-01-01

    Stresses that understanding the impact of interaction with mass media requires conceptualizing media as an institutionalized social form. A critical feature of this process is the grammatical character of media interaction in the form of rhythm and tempo, because these rhythms and tempos become established in everyday routine. (SKC)

  13. Reduced intrinsic heart rate is associated with reduced arrhythmic susceptibility in guinea-pig heart.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-12-01

    In the clinical setting, patients with slower resting heart rate are less prone to cardiovascular death compared with those with elevated heart rate. However, electrophysiological adaptations associated with reduced cardiac rhythm have not been thoroughly explored. In this study, relationships between intrinsic heart rate and arrhythmic susceptibility were examined by assessments of action potential duration (APD) rate adaptation and inducibility of repolarization alternans in sinoatrial node (SAN)-driven and atrioventricular (AV)-blocked guinea-pig hearts perfused with Langendorff apparatus. Electrocardiograms, epicardial monophasic action potentials, and effective refractory periods (ERP) were assessed in normokalemic and hypokalemic conditions. Slower basal heart rate in AV-blocked hearts was associated with prolonged ventricular repolarization during spontaneous beating, and with attenuated APD shortening at increased cardiac activation rates during dynamic pacing, when compared with SAN-driven hearts. During hypokalemic perfusion, the inducibility of repolarization alternans and tachyarrhythmia by rapid pacing was found to be lower in AV-blocked hearts. This difference was ascribed to prolonged ERP in the setting of reduced basal heart rate, which prevented ventricular capture at critically short pacing intervals required to induce arrhythmia. Reduced basal heart rate is associated with electrophysiological changes that prevent electrical instability upon an abrupt cardiac acceleration.

  14. Numerical modeling of dynamics of heart rate and arterial pressure during passive orthostatic test

    Science.gov (United States)

    Ishbulatov, Yu. M.; Kiselev, A. R.; Karavaev, A. S.

    2018-04-01

    A model of human cardiovascular system is proposed to describe the main heart rhythm, influence of autonomous regulation on frequency and strength of heart contractions and resistance of arterial vessels; process of formation of arterial pressure during systolic and diastolic phases; influence of respiration; synchronization between loops of autonomous regulation. The proposed model is used to simulate the dynamics of heart rate and arterial pressure during passive transition from supine to upright position. Results of mathematical modeling are compared to original experimental data.

  15. ‘Ragged Time’ in Intra-panel Comics Rhythms

    Directory of Open Access Journals (Sweden)

    Corry Shores

    2016-07-01

    Full Text Available A phenomenological method of comics analysis can be useful when we need to uncover the structural features of the comics experience itself. One fruitful application would be in the study of irregular intra-panel rhythms, where the temporalized divisions are not visibly indicated but rather are only experienced. By means of Gilles Deleuze’s notion of rhythmic repetition and his elaboration of it through Olivier Messiaen’s theory of ‘kinetic’ rhythm, we will formulate a conception of visual rhythm as being based on metrical irregularity. We further explicate this concept of irregular rhythm by drawing upon the notion of ‘ragged time’ in the early jazz musical form, ragtime. We finally test its usefulness by examining how the ‘jazzy’ rhythms of Cubist-styled panels by Art Spiegelman and Mary Fleener generate an experience of ragged time.

  16. Birkhoff normalization

    NARCIS (Netherlands)

    Broer, H.; Hoveijn, I.; Lunter, G.; Vegter, G.

    2003-01-01

    The Birkhoff normal form procedure is a widely used tool for approximating a Hamiltonian systems by a simpler one. This chapter starts out with an introduction to Hamiltonian mechanics, followed by an explanation of the Birkhoff normal form procedure. Finally we discuss several algorithms for

  17. Long-term statin therapy in patients with systolic heart failure and normal cholesterol: effects on elevated serum markers of collagen turnover, inflammation, and B-type natriuretic peptide.

    LENUS (Irish Health Repository)

    Abulhul, Esam

    2012-01-01

    The role of statin therapy in heart failure (HF) is unclear. The amino-terminal propeptide of procollagen type III (PIIINP) predicts outcome in HF, and yet there are conflicting reports of statin therapy effects on PIIINP.

  18. Changes of deceleration and acceleration capacity of heart rate in patients with acute hemispheric ischemic stroke

    Directory of Open Access Journals (Sweden)

    Xu YH

    2016-03-01

    Full Text Available Yan-Hong Xu,1 Xing-De Wang,2 Jia-Jun Yang,1 Li Zhou,2 Yong-Chao Pan1 1Department of Neurology, 2Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China Background and purpose: Autonomic dysfunction is common after stroke, which is correlated with unfavorable outcome. Phase-rectified signal averaging is a newly developed technique for assessing cardiac autonomic function, by detecting sympathetic and vagal nerve activity separately through calculating acceleration capacity (AC and deceleration capacity (DC of heart rate. In this study, we used this technique for the first time to investigate the cardiac autonomic function of patients with acute hemispheric ischemic stroke. Methods: A 24-hour Holter monitoring was performed in 63 patients with first-ever acute ischemic stroke in hemisphere and sinus rhythm, as well as in 50 controls with high risk of stroke. DC, AC, heart rate variability parameters, standard deviation of all normal-to-normal intervals (SDNN, and square root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals (RMSSD were calculated. The National Institutes of Health Stroke Scale (NIHSS was used to assess the severity of stroke. We analyzed the changes of DC, AC, SDNN, and RMSSD and also studied the correlations between these parameters and NIHSS scores. Results: The R–R (R wave to R wave on electrocardiogram intervals, DC, AC, and SDNN in the cerebral infarction group were lower than those in controls (P=0.003, P=0.002, P=0.006, and P=0.043, but the difference of RMSSD and the D-value and ratio between absolute value of AC (|AC| and DC were not statistically significant compared with those in controls. The DC of the infarction group was significantly correlated with |AC|, SDNN, and RMSSD (r=0.857, r=0.619, and r=0.358; P=0.000, P=0.000, and P=0.004. Correlation analysis also showed that DC, |AC|, and SDNN

  19. Definition and Classification of Heart Failure

    Directory of Open Access Journals (Sweden)

    Mitja Lainscak

    2017-01-01

    Full Text Available A review of the definition and classification of heart failure, updated since the recent 2016 European Society of Cardiology guidelines for the diagnosis and treatment of acute and chronic heart failure. Heart failure is defined by the European Society of Cardiology (ESC as a clinical syndrome characterised by symptoms such as shortness of breath, persistent coughing or wheezing, ankle swelling and fatigue, that may be accompanied by the following signs: jugular venous pressure, pulmonary crackles, increased heart rate and peripheral oedema. However, these signs may not be present in the early stages and in patients treated with diuretics. When apparent, they are due to a structural and/or functional cardiac abnormality, leading to systolic and/or diastolic ventricular dysfunction, resulting in a reduced cardiac output and/or elevated intra- cardiac pressures at rest or during stress. According to the most recent ESC guidelines the initial evaluation of patients with suspected heart failure should include a clinical history and physical examination, laboratory assessment, chest radiography, and electrocardiography. Echocardiography can confirm the diagnosis. Beyond detecting myocardial abnormality, other impairments such as abnormalities of the valves, pericardium, endocardium, heart rhythm, and conduction may be found. The identification of the underlying aetiology is pivotal for the diagnosis of heart failure and its treatment. The authors review the definitions and classifications of heart failure.

  20. Heart Failure with Preserved Ejection Fraction – Concept, Pathophysiology, Diagnosis and Challenges for Treatment

    Directory of Open Access Journals (Sweden)

    Lidija Veterovska Miljkovik

    2015-07-01

    Full Text Available Heart failure (HF with preserved left ventricular (LV ejection fraction (HFpEF occurs in 40 to 60% of the patients with HF, with a prognosis which is similar to HF with reduced ejection fraction (HFrEF. HFpEF pathophysiology is different from that of HFrEF, and has been characterized with diastolic dysfunction. Diastolic dysfunction has been defined with elevated left ventricular stiffness, prolonged iso-volumetric LV relaxation, slow LV filing and elevated LV end-diastolic pressure. Arterial hypertension occurs in majority cases with HFpEF worldwide. Patients are mostly older and obese. Diabetes mellitus and atrial fibrillation appear proportionally in a high frequency of patients with HFpEF. The HFpEF diagnosis is based on existence of symptoms and signs of heart failure, normal or approximately normal ejection and diagnosing of LV diastolic dysfunction by means of heart catheterization or Doppler echocardiography and/or elevated concentration of plasma natriuretic peptide. The present recommendations for HFpEF treatment include blood pressure control, heart chamber frequency control when atrial fibrillation exists, in some situations even coronary revascularization and an attempt for sinus rhythm reestablishment. Up to now, it is considered that no medication or a group of medications improve the survival of HFpEF patients. Due to these causes and the bad prognosis of the disorder, rigorous control is recommended of the previously mentioned precipitating factors for this disorder. This paper presents a universal review of the most important parameters which determine this disorder.

  1. Permanent atrial fibrillation in heart failure patients as another condition with increased reverse triiodothyronine concentration.

    Science.gov (United States)

    Jakowczuk, Maciej; Zalas, Dominika; Owecki, Maciej

    2016-09-01

    To fully investigate the thyroid hormonal function in patients with the most common arrhythmia - atrial fibrillation. 120 patients (aged 55-85 yrs) with symptoms of congestive heart failure exacerbation and no other concomitant disorders (inclusion criteria: normal cardiac troponin T at admission and 12 hours after, normal renal, hepatic and respiratory function; exclusion criteria: inflammatory state, history of myocardial infarction). Depending on the presence of permanent atrial fibrillation (PAF), patients were divided into two groups: PAF (34 females, 26 males) and regular sinus heart rhythm (43 females, 17 males), the groups did not differ in terms of heart rate, blood pressure, presence of overt/subclinical thyroid dysfunction, and medical therapy used. In all subjects thyroid stimulating hormone, free thyroxine, free triiodothyronine, reverse triiodothyronine were measured; echocardiography was performed. PAF group showed higher FT4 and rT3 (1.41 vs. 1.27 ng/dl, p=0.0007; 0.61 vs. 0.32 ng/ml, p<0.0001, respectively). With ROC curve analysis the biochemical thyroid related factor of the highest prognostic value for PAF occurrence (with the highest sensitivity and specificity: 77% and 72%, respectively) was rT3 with the cut-off of above 0.3 ng/ml. Also, a positive correlation between rT3 levels and left ventricular posterior wall diameter was observed (Spearman's correlation coefficient 0.33, p=0.0093). PAF is another condition where an increase in rT3 is observed. rT3 concentration above 0.3 ng/ml may be a novel biochemical sign associated with the presence of PAF in patients with chronic heart failure.

  2. Cross-cultural influences on rhythm processing: reproduction, discrimination, and beat tapping.

    Science.gov (United States)

    Cameron, Daniel J; Bentley, Jocelyn; Grahn, Jessica A

    2015-01-01

    The structures of musical rhythm differ between cultures, despite the fact that the ability to entrain movement to musical rhythm occurs in virtually all individuals across cultures. To measure the influence of culture on rhythm processing, we tested East African and North American adults on perception, production, and beat tapping for rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were the same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced by the