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Sample records for abnormal heart rhythms

  1. Heart Rhythm Society

    MedlinePlus

    ... Search: Education & Meetings Scientific Sessions Certified Education Courses & Online Learning Heart Rhythm On Demand Co-Sponsored & Endorsed Events ... Education & Meetings less Scientific Sessions Certified Education Courses & Online Learning Heart Rhythm On Demand Co-Sponsored & Endorsed Events ...

  2. Find a Heart Rhythm Specialist

    MedlinePlus

    ... Search: Education & Meetings Scientific Sessions Certified Education Courses & Online Learning Heart Rhythm On Demand Co-Sponsored & Endorsed Events ... Education & Meetings less Scientific Sessions Certified Education Courses & Online Learning Heart Rhythm On Demand Co-Sponsored & Endorsed Events ...

  3. Substances and Heart Rhythm Disorders

    MedlinePlus

    ... in others. These rhythm problems are rarely serious. Substance Abuse: Drugs and Inhalants Abusing legal or illegal drugs ... people, alcohol can cause heart rhythm disturbances. Alcohol abuse is a major risk factor for High ... herbs and other substances used in over-the-counter remedies are believed ...

  4. Recognizing an Irregular Heart Rhythm

    MedlinePlus

    ... a workout, consider checking your rhythm as well. Atrial fibrillation, also referred to as AF, is a common ... upper chambers, or atria, of the heart. “While atrial fibrillation is not common among young people, it can ...

  5. Assessment of Time and Frequency Domain Parameters of Heart Rate Variability and Interictal Cardiac Rhythm Abnormalities in Drug-naïve Patients with Idiopathic Generalized Epilepsy

    PubMed Central

    Kilinc, Ozden; Cincin, Altug; Pehlivan, Aslihan; Midi, Ipek; Kepez, Alper; Agan, Kadriye

    2016-01-01

    Background and Purpose: Epilepsy is a disease known to occur with autonomous phenomenons. Earlier studies indicate decreased heart rate variability (HRV) during ictal and interictal periods among epilepsy patients. In this study, we aim to investigate cardiac rhythm abnormalities and HRV during interictal period between drug-naïve patients with idiopathic generalized epilepsy (IGE) and healthy control group. Methods: Twenty-six patients with IGE and 26 healthy individuals included in the study. In order to eliminate any structural cardiac pathology, transthoracic echocardiography was performed in all subjects and time and frequency domain parameters of HRV were evaluated after 24-hour rhythm holter monitoring. Results: Between two groups, no significant difference was detected in terms of mean heart rate and maximum duration between the start of the Q waves and the end of the T waves (QT intervals). In the time domain analysis of HRV, no statically significant difference was detected for standard deviation of all R - R intervals and root-mean-square of successive differences between patient and control group (p = 0,070 and p = 0,104 respectively). In the frequency domain analysis of HRV, patients tended to display lower total power and very low frequency power than did healthy subjects, but the differences were not statistically significant. Conclusions: Our results suggest that there is no major effect of the epilepsy on HRV in patients with IGE. It should be emphasized that, in this study, HRV was evaluated only in patients with IGE and that the results are not proper to be generalized for patients with partial seizures. PMID:27390676

  6. Nonlinear properties of cardiac rhythm abnormalities

    NASA Astrophysics Data System (ADS)

    Liebovitch, Larry S.; Todorov, Angelo T.; Zochowski, Michal; Scheurle, Daniela; Colgin, Laura; Wood, Mark A.; Ellenbogen, Kenneth A.; Herre, John M.; Bernstein, Robert C.

    1999-03-01

    Many physical processes have distributions of times between events that have non-normalizable, power law probability density functions (PDF's). The moments of such distributions are not defined. We found that the PDF's of the times between events of ventricular tachyarrhythmia (rapid heart rate) and premature ventricular contractions have a power law form indicative of a non-normalizable distribution, and that the timing between these events cannot be meaningfully characterized by the mean frequency of such events. The Hurst analysis showed that there were self-similar correlations in the data. These results indicate that the physical processes that disrupt the normal rhythm of the heart produce a fractal pattern in the timing between these events. It also suggests that the mean and the variance of the frequency of these events may not be good measures to assess the status of patients with these arrhythmias and determine the effectiveness of therapeutic procedures.

  7. An Artificial Vector Model for Generating Abnormal Electrocardiographic Rhythms

    PubMed Central

    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. PMID:20308774

  8. Quantifying Speech Rhythm Abnormalities in the Dysarthrias

    ERIC Educational Resources Information Center

    Liss, Julie M.; White, Laurence; Mattys, Sven L.; Lansford, Kaitlin; Lotto, Andrew J.; Spitzer, Stephanie M.; Caviness, John N.

    2009-01-01

    Purpose: In this study, the authors examined whether rhythm metrics capable of distinguishing languages with high and low temporal stress contrast also can distinguish among control and dysarthric speakers of American English with perceptually distinct rhythm patterns. Methods: Acoustic measures of vocalic and consonantal segment durations were…

  9. Heart rhythm during permanent cardiac pacing.

    PubMed Central

    Edhag, O; Rosenqvist, M

    1979-01-01

    Heart rhythm was analysed with regard to spontaneous or pacemaker-induced heart activity, in a consecutive series of 282 patients paced for at least 1 year. The mean duration of pacing was 59 (13 to 180) months. The mean age of the patients was 76 (39 to 93) years. Spontaneous heart activity at all routine examinations was found in 33 (12%) of the patients. Pacemaker-induced rhythm only was recorded in 42 per cent of the patients whereas the remaining 46 per cent had varying electrocardiographic patterns. Of the patients with spontaneous rhythm at each visit, 10 had had complete heart block before pacing. Regular sinus activity was recorded at every routine examination in 74 per cent of the patients paced for reasons other than the sick sinus syndrome. This indicated that a substantial number of paced patients might be candidates for atrial triggered pacing. Patients treated with digitalis more often had asystole at the time of replacement of the pacemaker (32%) than those not so treated (19). This suggests an increased risk of sudden death in paced patients on digitalis if the pacemaker fails. PMID:486279

  10. Practical stepwise approach to rhythm disturbances in congenital heart diseases.

    PubMed

    Huh, June

    2010-06-01

    Patients with congenital heart diseases (CHD) are confronted with early- and late-onset complications, such as conduction disorders, arrhythmias, myocardial dysfunction, altered coronary flow, and ischemia, throughout their lifetime despite successful hemodynamic and/or anatomical correction. Rhythm disturbance is a well-known and increasingly frequent cause of morbidity and mortality in patients with CHD. Predisposing factors to rhythm disturbances include underlying cardiac defects, hemodynamic changes as part of the natural history, surgical repair and related scarring, and residual hemodynamic abnormalities. Acquired factors such as aging, hypertension, diabetes, obesity, and others may also contribute to arrhythmogenesis in CHD. The first step in evaluating arrhythmias in CHD is to understand the complex anatomy and to find predisposing factors and hemodynamic abnormalities. A practical stepwise approach can lead to diagnosis and prompt appropriate interventions. Electrophysiological assessment and management should be done with integrated care of the underlying heart defects and hemodynamic abnormalities. Catheter ablation and arrhythmia surgery have been increasingly applied, showing increasing success rates with technological advancement despite complicated arrhythmia circuits in complex anatomy and the difficulty of access. Correction of residual hemodynamic abnormalities may be critical in the treatment of arrhythmia in patients with CHD. PMID:21189938

  11. Practical stepwise approach to rhythm disturbances in congenital heart diseases

    PubMed Central

    2010-01-01

    Patients with congenital heart diseases (CHD) are confronted with early- and late-onset complications, such as conduction disorders, arrhythmias, myocardial dysfunction, altered coronary flow, and ischemia, throughout their lifetime despite successful hemodynamic and/or anatomical correction. Rhythm disturbance is a well-known and increasingly frequent cause of morbidity and mortality in patients with CHD. Predisposing factors to rhythm disturbances include underlying cardiac defects, hemodynamic changes as part of the natural history, surgical repair and related scarring, and residual hemodynamic abnormalities. Acquired factors such as aging, hypertension, diabetes, obesity, and others may also contribute to arrhythmogenesis in CHD. The first step in evaluating arrhythmias in CHD is to understand the complex anatomy and to find predisposing factors and hemodynamic abnormalities. A practical stepwise approach can lead to diagnosis and prompt appropriate interventions. Electrophysiological assessment and management should be done with integrated care of the underlying heart defects and hemodynamic abnormalities. Catheter ablation and arrhythmia surgery have been increasingly applied, showing increasing success rates with technological advancement despite complicated arrhythmia circuits in complex anatomy and the difficulty of access. Correction of residual hemodynamic abnormalities may be critical in the treatment of arrhythmia in patients with CHD. PMID:21189938

  12. European Heart Rhythm Association Summit report 2014.

    PubMed

    Sutton, Richard; Leclercq, Christophe; Kuck, Karl-Heinz

    2016-05-01

    Across Europe, the role of the welfare state is constantly being questioned and even eroded. At the same time, funding sources for post-graduate medical education and training are under attack as regulators review the working relationships between physicians and industry. Both of these issues have profound consequences for cardiologists and their patients, and were, therefore, chosen as the themes of the European Heart Rhythm Association (EHRA) 2014 Spring Summit held at Heart House, Sophia Antipolis, 25-26 March 2014. The meeting noted that some of the changes are already affecting patient care standards and that this is exacerbated by a reduction in research and education programmes. The principle conclusion was that EHRA must find better means of engagement with the authorities across Europe to ensure that its views are considered and that ethical patient care is preserved. Participants were particularly alarmed by the example from Sweden in which future healthcare planning appears to exclude the views of physicians, although this is not yet the case in other countries. The demand for greater transparency in relationships between physicians and industry was also discussed. Although intended to eliminate corruption, concern was expressed that such moves would cause long-term damage to education and research, threatening the future of congresses, whose role in these areas appears underestimated by the authorities. PMID:26467405

  13. Death of Loved One May Trigger Heart Rhythm Trouble

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_158176.html Death of Loved One May Trigger Heart Rhythm Trouble ... likely to develop an irregular heartbeat following the death of their spouse or life partner, particularly if ...

  14. ECG patch monitors for assessment of cardiac rhythm abnormalities.

    PubMed

    Lobodzinski, S Suave

    2013-01-01

    The primary goal of long-term monitoring is the improvement of diagnostic yield. Despite the clear utility of Holter monitoring in clinical cardiology, issues of relatively low diagnostic yield, cost and inconvenience have motivated the development of ultra-portable devices referred to as ECG patch monitors. Although the "gold standard" for assessing cardiac rhythm abnormalities remains a 12-lead Holter, there is an increasing interest in portable monitoring devices that provide the opportunity for evaluating cardiac rhythm in real-world environments such as the workplace or home. To facilitate patient acceptance these monitors underwent a radical miniaturization and redesign to include wireless communication, water proofing and a patch carrier for attaching devices directly to the skin. We review recent developments in the field of "patch" devices primarily designed for very long-term monitoring of cardiac arrhythmic events. As the body of supporting clinical validation data grows, these devices hold promise for a variety of cardiac monitoring applications. From a clinical and research standpoint, the capacity to obtain longitudinal cardiac activity data by patch devices may have significant implications for device selection, monitoring duration, and care pathways for arrhythmia evaluation and atrial fibrillation surveillance. From a research standpoint, the new devices may allow for the development of novel diagnostic algorithms with the goal of finding patterns and correlations with exercise and drug regimens. PMID:24215754

  15. Role of diabetes in heart rhythm disorders

    PubMed Central

    Koektuerk, Buelent; Aksoy, Murat; Horlitz, Marc; Bozdag-Turan, Ilkay; Turan, Ramazan Goekmen

    2016-01-01

    The incidence of diabetes mellitus (DM) is increasing rapidly. DM is the leading cause of cardiovascular diseases, which can lead to varied cardiovascular complications by aggravated atherosclerosis in large arteries and coronary atherosclerosis, thereby grows the risk for macro and microangiopathy such as myocardial infarction, stroke, limb loss and retinopathy. Moreover diabetes is one of the strongest and independent risk factor for cardiovascular morbidity and mortality, which is associated frequently with rhythm disorders such as atrial fibrillation (AF) and ventricular arrhythmias (VA). The present article provides a concise overview of the association between DM and rhythm disorders such as AF and VA with underlying pathophysiological mechanisms. PMID:26862372

  16. Musical rhythms in heart period dynamics: a cross-cultural and interdisciplinary approach to cardiac rhythms.

    PubMed

    Bettermann, H; Amponsah, D; Cysarz, D; van Leeuwen, P

    1999-11-01

    The purpose of this study was to expand classic heart period analysis methods by techniques from ethnomusicology that explicitly take complex musical rhythm principles into consideration. The methods used are based on the theory of African music, the theory of symbolic dynamics, and combinatorial theory. Heart period tachograms from 192 24-h electrocardiograms of 96 healthy subjects were transformed into binary symbol sequences that were interpretable as elementary rhythmic (percussive) patterns, the time lines in African music. Using a hierarchical rhythm pattern scheme closely related to the Derler Rhythm Classification (from jazz theory), we calculated the predominance and stability of pattern classes. The results show that during sleep certain classes, specific to individuals, occurred in a cyclically recurrent manner and many times more often than expected. Simultaneously, other classes disappeared more or less completely. Moreover, the most frequent classes obviously originate from phase-locking processes in autonomic regulation (e.g., between respiratory and cardiac cycles). In conclusion, the new interdisciplinary method presented here demonstrates that heart period patterns, in particular those occurring during night sleep, can be interpreted as musical rhythms. This method may be of great potential use in music therapy research. PMID:10564129

  17. Reversible heart rhythm complexity impairment in patients with primary aldosteronism

    NASA Astrophysics Data System (ADS)

    Lin, Yen-Hung; Wu, Vin-Cent; Lo, Men-Tzung; Wu, Xue-Ming; Hung, Chi-Sheng; Wu, Kwan-Dun; Lin, Chen; Ho, Yi-Lwun; Stowasser, Michael; Peng, Chung-Kang

    2015-08-01

    Excess aldosterone secretion in patients with primary aldosteronism (PA) impairs their cardiovascular system. Heart rhythm complexity analysis, derived from heart rate variability (HRV), is a powerful tool to quantify the complex regulatory dynamics of human physiology. We prospectively analyzed 20 patients with aldosterone producing adenoma (APA) that underwent adrenalectomy and 25 patients with essential hypertension (EH). The heart rate data were analyzed by conventional HRV and heart rhythm complexity analysis including detrended fluctuation analysis (DFA) and multiscale entropy (MSE). We found APA patients had significantly decreased DFAα2 on DFA analysis and decreased area 1-5, area 6-15, and area 6-20 on MSE analysis (all p < 0.05). Area 1-5, area 6-15, area 6-20 in the MSE study correlated significantly with log-transformed renin activity and log-transformed aldosterone-renin ratio (all p < = 0.01). The conventional HRV parameters were comparable between PA and EH patients. After adrenalectomy, all the altered DFA and MSE parameters improved significantly (all p < 0.05). The conventional HRV parameters did not change. Our result suggested that heart rhythm complexity is impaired in APA patients and this is at least partially reversed by adrenalectomy.

  18. Predictability of normal heart rhythms and deterministic chaos

    NASA Astrophysics Data System (ADS)

    Lefebvre, J. H.; Goodings, D. A.; Kamath, M. V.; Fallen, E. L.

    1993-04-01

    The evidence for deterministic chaos in normal heart rhythms is examined. Electrocardiograms were recorded of 29 subjects falling into four groups—a young healthy group, an older healthy group, and two groups of patients who had recently suffered an acute myocardial infarction. From the measured R-R intervals, a time series of 1000 first differences was constructed for each subject. The correlation integral of Grassberger and Procaccia was calculated for several subjects using these relatively short time series. No evidence was found for the existence of an attractor having a dimension less than about 4. However, a prediction method recently proposed by Sugihara and May and an autoregressive linear predictor both show that there is a measure of short-term predictability in the differenced R-R intervals. Further analysis revealed that the short-term predictability calculated by the Sugihara-May method is not consistent with the null hypothesis of a Gaussian random process. The evidence for a small amount of nonlinear dynamical behavior together with the short-term predictability suggest that there is an element of deterministic chaos in normal heart rhythms, although it is not strong or persistent. Finally, two useful parameters of the predictability curves are identified, namely, the `first step predictability' and the `predictability decay rate,' neither of which appears to be significantly correlated with the standard deviation of the R-R intervals.

  19. Heart rhythm complexity impairment in patients undergoing peritoneal dialysis.

    PubMed

    Lin, Yen-Hung; Lin, Chen; Ho, Yi-Heng; Wu, Vin-Cent; Lo, Men-Tzung; Hung, Kuan-Yu; Liu, Li-Yu Daisy; Lin, Lian-Yu; Huang, Jenq-Wen; Peng, Chung-Kang

    2016-01-01

    Cardiovascular disease is one of the leading causes of death in patients with advanced renal disease. The objective of this study was to investigate impairments in heart rhythm complexity in patients with end-stage renal disease. We prospectively analyzed 65 patients undergoing peritoneal dialysis (PD) without prior cardiovascular disease and 72 individuals with normal renal function as the control group. Heart rhythm analysis including complexity analysis by including detrended fractal analysis (DFA) and multiscale entropy (MSE) were performed. In linear analysis, the PD patients had a significantly lower standard deviation of normal RR intervals (SDRR) and percentage of absolute differences in normal RR intervals greater than 20 ms (pNN20). Of the nonlinear analysis indicators, scale 5, area under the MSE curve for scale 1 to 5 (area 1-5) and 6 to 20 (area 6-20) were significantly lower than those in the control group. In DFA anaylsis, both DFA α1 and DFA α2 were comparable in both groups. In receiver operating characteristic curve analysis, scale 5 had the greatest discriminatory power for two groups. In both net reclassification improvement model and integrated discrimination improvement models, MSE parameters significantly improved the discriminatory power of SDRR, pNN20, and pNN50. In conclusion, PD patients had worse cardiac complexity parameters. MSE parameters are useful to discriminate PD patients from patients with normal renal function. PMID:27324066

  20. Heart rhythm complexity impairment in patients undergoing peritoneal dialysis

    NASA Astrophysics Data System (ADS)

    Lin, Yen-Hung; Lin, Chen; Ho, Yi-Heng; Wu, Vin-Cent; Lo, Men-Tzung; Hung, Kuan-Yu; Liu, Li-Yu Daisy; Lin, Lian-Yu; Huang, Jenq-Wen; Peng, Chung-Kang

    2016-06-01

    Cardiovascular disease is one of the leading causes of death in patients with advanced renal disease. The objective of this study was to investigate impairments in heart rhythm complexity in patients with end-stage renal disease. We prospectively analyzed 65 patients undergoing peritoneal dialysis (PD) without prior cardiovascular disease and 72 individuals with normal renal function as the control group. Heart rhythm analysis including complexity analysis by including detrended fractal analysis (DFA) and multiscale entropy (MSE) were performed. In linear analysis, the PD patients had a significantly lower standard deviation of normal RR intervals (SDRR) and percentage of absolute differences in normal RR intervals greater than 20 ms (pNN20). Of the nonlinear analysis indicators, scale 5, area under the MSE curve for scale 1 to 5 (area 1–5) and 6 to 20 (area 6–20) were significantly lower than those in the control group. In DFA anaylsis, both DFA α1 and DFA α2 were comparable in both groups. In receiver operating characteristic curve analysis, scale 5 had the greatest discriminatory power for two groups. In both net reclassification improvement model and integrated discrimination improvement models, MSE parameters significantly improved the discriminatory power of SDRR, pNN20, and pNN50. In conclusion, PD patients had worse cardiac complexity parameters. MSE parameters are useful to discriminate PD patients from patients with normal renal function.

  1. Heart rhythm complexity impairment in patients undergoing peritoneal dialysis

    PubMed Central

    Lin, Yen-Hung; Lin, Chen; Ho, Yi-Heng; Wu, Vin-Cent; Lo, Men-Tzung; Hung, Kuan-Yu; Liu, Li-Yu Daisy; Lin, Lian-Yu; Huang, Jenq-Wen; Peng, Chung-Kang

    2016-01-01

    Cardiovascular disease is one of the leading causes of death in patients with advanced renal disease. The objective of this study was to investigate impairments in heart rhythm complexity in patients with end-stage renal disease. We prospectively analyzed 65 patients undergoing peritoneal dialysis (PD) without prior cardiovascular disease and 72 individuals with normal renal function as the control group. Heart rhythm analysis including complexity analysis by including detrended fractal analysis (DFA) and multiscale entropy (MSE) were performed. In linear analysis, the PD patients had a significantly lower standard deviation of normal RR intervals (SDRR) and percentage of absolute differences in normal RR intervals greater than 20 ms (pNN20). Of the nonlinear analysis indicators, scale 5, area under the MSE curve for scale 1 to 5 (area 1–5) and 6 to 20 (area 6–20) were significantly lower than those in the control group. In DFA anaylsis, both DFA α1 and DFA α2 were comparable in both groups. In receiver operating characteristic curve analysis, scale 5 had the greatest discriminatory power for two groups. In both net reclassification improvement model and integrated discrimination improvement models, MSE parameters significantly improved the discriminatory power of SDRR, pNN20, and pNN50. In conclusion, PD patients had worse cardiac complexity parameters. MSE parameters are useful to discriminate PD patients from patients with normal renal function. PMID:27324066

  2. [Semi-automatic defibrillators does not always interpret heart rhythms correctly. Five patients were defibrillated despite non-shockable rhythms].

    PubMed

    Wangenheim, Burkard; Israelsson, Johan; Lindstaedt, Michael; Carlsson, Jörg

    2015-01-01

    Automated external defibrillators (AED) have become an important part of the »the chain of survival« in case of sudden cardiac arrest (SCA), where early defibrillation is lifesaving. The American Heart Association demands that AEDs have a specificity of >99 % to recognize normal sinus rhythm and >95 % for the other non-shockable rhythms. Reports on their performance in the field are scarce. We present five cases in which AED recommended shock for apparently non-shockable rhythms. This indicates the necessity to systematically reevaluate AED performance. PMID:26241809

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

    NASA Astrophysics Data System (ADS)

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

    2002-03-01

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

  4. Health economics and the European Heart Rhythm Association.

    PubMed

    Vardas, Panos; Boriani, Giuseppe

    2011-05-01

    The management of healthcare is becoming extremely complex in developed countries, as a result of increasing age of the population and increasing costs of care, coupled with diminishing resources due to global financial crisis. This situation threatens access to appropriate care, and a more or less explicit rationing of some types of treatment may occur in 'real world' clinical practice. This is particularly true for those treatments or interventions with a relatively high up-front cost, such as cardioverter defibrillators, devices for cardiac resynchronization therapy or ablation procedures for atrial fibrillation. The European Heart Rhythm Association (EHRA) is strongly convinced that the skills of electrophysiologists and cardiologists responsible for the management of rhythm disorders have to evolve, also embracing the knowledge of health economics, clinical epidemiology, health-care management and outcome research. These disciplines do not belong to what is considered as the conventional cultural background of physicians, but knowledge of comparative cost effectiveness and of other economic approaches nowadays appears fundamental for a dialogue with a series of stakeholders, such as policy makers, politicians, and administrators, involved in budgeting the activity of hospitals and health-care services, as well as in approaching health technology assessment. PMID:21518741

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

    PubMed

    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. PMID:21682138

  6. Mutations in SGOL1 cause a novel cohesinopathy affecting heart and gut rhythm.

    PubMed

    Chetaille, Philippe; Preuss, Christoph; Burkhard, Silja; Côté, Jean-Marc; Houde, Christine; Castilloux, Julie; Piché, Jessica; Gosset, Natacha; Leclerc, Séverine; Wünnemann, Florian; Thibeault, Maryse; Gagnon, Carmen; Galli, Antonella; Tuck, Elizabeth; Hickson, Gilles R; El Amine, Nour; Boufaied, Ines; Lemyre, Emmanuelle; de Santa Barbara, Pascal; Faure, Sandrine; Jonzon, Anders; Cameron, Michel; Dietz, Harry C; Gallo-McFarlane, Elena; Benson, D Woodrow; Moreau, Claudia; Labuda, Damian; Zhan, Shing H; Shen, Yaoqing; Jomphe, Michèle; Jones, Steven J M; Bakkers, Jeroen; Andelfinger, Gregor

    2014-11-01

    The pacemaking activity of specialized tissues in the heart and gut results in lifelong rhythmic contractions. Here we describe a new syndrome characterized by Chronic Atrial and Intestinal Dysrhythmia, termed CAID syndrome, in 16 French Canadians and 1 Swede. We show that a single shared homozygous founder mutation in SGOL1, a component of the cohesin complex, causes CAID syndrome. Cultured dermal fibroblasts from affected individuals showed accelerated cell cycle progression, a higher rate of senescence and enhanced activation of TGF-β signaling. Karyotypes showed the typical railroad appearance of a centromeric cohesion defect. Tissues derived from affected individuals displayed pathological changes in both the enteric nervous system and smooth muscle. Morpholino-induced knockdown of sgol1 in zebrafish recapitulated the abnormalities seen in humans with CAID syndrome. Our findings identify CAID syndrome as a novel generalized dysrhythmia, suggesting a new role for SGOL1 and the cohesin complex in mediating the integrity of human cardiac and gut rhythm. PMID:25282101

  7. Heart palpitations

    MedlinePlus

    Heart palpitations can be due to: Anxiety, stress, panic attack, or fear Caffeine intake Nicotine intake Cocaine or other illegal drugs Diet pills Exercise Fever However, some palpitations are due to an abnormal heart rhythm, ...

  8. Common Abnormal Heart Rhythm Linked to Cancer Risk

    MedlinePlus

    ... published online May 25 in the journal JAMA Cardiology . Dr. Emelia Benjamin is a professor of medicine ... University School of Medicine; May 25, 2016, JAMA Cardiology , online HealthDay Copyright (c) 2016 HealthDay . All rights ...

  9. Common Abnormal Heart Rhythm Linked to Cancer Risk

    MedlinePlus

    ... found an association and doesn't prove that atrial fibrillation causes cancer To use the sharing features on ... study suggests. "We found a significant relationship between atrial fibrillation and cancer," said lead researcher Dr. David Conen, ...

  10. Alterations in the heart rate and activity rhythms of three orbital astronauts on a space mission.

    PubMed

    Liu, Zhizhen; Wan, Yufeng; Zhang, Lin; Tian, Yu; Lv, Ke; Li, Yinghui; Wang, Chunhui; Chen, Xiaoping; Chen, Shanguang; Guo, Jinhu

    2015-01-01

    Environmental factors in space are dramatically different from those on Earth. The spaceflight environment has been known to influence human physiology and behavior on orbital missions. In this study, we investigated alterations in the diurnal rhythms of activity and heart rate of three Chinese astronauts on a space mission. An analysis of the heart rate data showed a significant decrease in heart rate amplitudes during flight in all three subjects. The heart rate amplitudes of all the three astronauts were significantly dampened during flight, and the minimum as well as the maximum value of heart rate increased after flight. A phase shift in heart rate was observed in one of the three astronauts after flight. These results demonstrate the influence of spaceflight on heart physiology and function. In addition, a significant decrease in body trunk activity and rhythmicity occurred during flight, demonstrating that the spaceflight environment disturbs motion adaptation and diurnal activity rhythms. PMID:26177621

  11. Resting state cortical electroencephalographic rhythms in subjects with normal and abnormal body weight.

    PubMed

    Babiloni, Claudio; Marzano, Nicola; Lizio, Roberta; Valenzano, Anna; Triggiani, Antonio Ivano; Petito, Annamaria; Bellomo, Antonello; Lecce, Brunello; Mundi, Ciro; Soricelli, Andrea; Limatola, Cristina; Cibelli, Giuseppe; Del Percio, Claudio

    2011-09-15

    It is well known that resting state regional cerebral blood flow is abnormal in obese when compared to normal-weight subjects but the underlying neurophysiological mechanisms are poorly known. To address this issue, we tested the hypothesis that amplitude of resting state cortical electroencephalographic (EEG) rhythms differ among underweight, normal-weight, and overweight/obese subjects as a reflection of the relationship between cortical neural synchronization and regulation of body weight. Eyes-closed resting state EEG data were recorded in 16 underweight subjects, 25 normal-weight subjects, and 18 overweight/obese subjects. All subjects were psychophysically healthy (no eating disorders or major psychopathologies). EEG rhythms of interest were delta (2-4Hz), theta (4-8Hz), alpha 1 (8-10.5Hz), alpha 2 (10.5-13Hz), beta 1 (13-20Hz), beta 2 (20-30Hz), and gamma (30-40Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography (LORETA). Statistical results showed that parietal and temporal alpha 1 sources fitted the pattern underweight>normal-weight>overweight/obese (p<0.004), whereas occipital alpha 1 sources fitted the pattern normal-weight>underweight>overweight/obese (p<0.00003). Furthermore, amplitude of the parietal, occipital, and temporal alpha 2 sources was stronger in the normal-weight subjects than in the underweight and overweight/obese subjects (p<0.0007). These results suggest that abnormal weight in healthy overweight/obese subjects is related to abnormal cortical neural synchronization at the basis of resting state alpha rhythms and fluctuation of global brain arousal. PMID:21704716

  12. Central Mechanisms of Abnormal Sympathoexcitation in Chronic Heart Failure

    PubMed Central

    Kishi, Takuya; Hirooka, Yoshitaka

    2012-01-01

    It has been recognized that the sympathetic nervous system is abnormally activated in chronic heart failure, and leads to further worsening chronic heart failure. In the treatment of chronic heart failure many clinical studies have already suggested that the inhibition of the abnormal sympathetic hyperactivity by beta blockers is beneficial. It has been classically considered that abnormal sympathetic hyperactivity in chronic heart failure is caused by the enhancement of excitatory inputs including changes in peripheral baroreceptor and chemoreceptor reflexes and chemical mediators that control sympathetic outflow. Recently, the abnormalities in the central regulation of sympathetic nerve activity mediated by brain renin angiotensin system-oxidative stress axis and/or proinflammatory cytokines have been focused. Central renin angiotensin system, proinflammatory cytokines, and the interaction between them have been determined as the target of the sympathoinhibitory treatment in experimental animal models with chronic heart failure. In conclusion, we must recognize that chronic heart failure is a syndrome with an abnormal sympathoexcitation, which is caused by the abnormalities in the central regulation of sympathetic nerve activity. PMID:22919539

  13. Circadian rhythm abnormalities - Association with the course of inflammatory bowel disease.

    PubMed

    Sobolewska-Włodarczyk, Aleksandra; Włodarczyk, Marcin; Szemraj, Janusz; Stec-Michalska, Krystyna; Fichna, Jakub; Wiśniewska-Jarosińska, Maria

    2016-08-01

    Crohn's disease (CD) and ulcerative colitis (UC) are the main representatives of inflammatory bowel diseases (IBD), a group of chronic, immune system-mediated inflammatory diseases of the gastrointestinal (GI) tract. The pathogenesis of the intestinal lesions in IBD is not entirely identified and understood: excessive activation of the immune system may come as a result of the interaction of various environmental and infectious factors, genetic predisposition, and the mediation of abnormal intestinal flora. The main objective of the current study is to further identify the risk factors for the development of IBD. Currently, there is very little knowledge about circadian rhythm and IBD and there are only a few studies on the relationship between sleep disturbances and the course of the disease, as well as pro- and anti-inflammatory cytokine profile and general immune system functioning. Furthermore, the relationship between the expression of circadian rhythm genes and severe course of IBD is still unknown. The aim of this review is to show the current state of knowledge about the relationship between circadian rhythm disorders, sleep disturbance and inflammation in the GI tract and to analyze the possibility of employing this knowledge in diagnosis and treatment of IBD. PMID:27166084

  14. Heart rate dynamics distinguish among atrial fibrillation, normal sinus rhythm and sinus rhythm with frequent ectopy.

    PubMed

    Carrara, Marta; Carozzi, Luca; Moss, Travis J; de Pasquale, Marco; Cerutti, Sergio; Ferrario, Manuela; Lake, Douglas E; Moorman, J Randall

    2015-09-01

    Atrial fibrillation (AF) is usually detected by inspection of the electrocardiogram waveform, a task made difficult when the signal is distorted by noise. The RR interval time series is more frequently available and accurate, yet linear and nonlinear time series analyses that detect highly varying and irregular AF are vulnerable to the common finding of frequent ectopy. We hypothesized that different nonlinear measures might capture characteristic features of AF, normal sinus rhythm (NSR), and sinus rhythm (SR) with frequent ectopy in ways that linear measures might not. To test this, we studied 2722 patients with 24 h ECG recordings in the University of Virginia Holter database. We found dynamical phenotypes for the three rhythm classifications. As expected, AF records had the highest variability and entropy, and NSR the lowest. SR with ectopy could be distinguished from AF, which had higher entropy, and from NSR, which had different fractal scaling, measured as higher detrended fluctuation analysis slope. With these dynamical phenotypes, we developed successful classification strategies, and the nonlinear measures improved on the use of mean and variability alone, even after adjusting for age. Final models using all variables had excellent performance, with positive predictive values for AF, NSR and SR with ectopy as high as 97, 98 and 90%, respectively. Since these classifiers can reliably detect rhythm changes utilizing segments as short as 10 min, we envision their application in noisy settings and in personal monitoring devices where only RR interval time series may be available. PMID:26246162

  15. Heart rhythm disturbances associated with rupatadine: a case series from the Spanish and Portuguese pharmacovigilance systems.

    PubMed

    Carvajal, A; Macías, D; Salado, I; Sáinz, M; Ortega, S; Campo, C; García del Pozo, J; Martín Arias, L H; Velasco, A; Gonçalves, S; Pombal, R; Carmona, R

    2009-05-01

    We searched the Spanish and Portuguese pharmacovigilance databases for spontaneous case reports of heart rhythm disturbances associated with rupatadine and other new H1 antihistamines. Five cases were found involving patients treated with rupatadine (13.9% of all reports relating to this drug). In all five cases, the reaction started after exposure and resolved when the drug was discontinued. In two cases, rupatadine was the only medication being taken by the patient, and no other condition that could explain the heart rhythm disturbances was diagnosed. The reporting odds ratio was 3.2 (95% confidence interval, 1.0-10.5). The reporting rate was 2 cases per 100,000 patients treated per year (95% confidence interval, 0.4-6.0). These results suggest a causal relationship between rupatadine and heart rhythm disturbances. PMID:19225450

  16. Pharmacologic Approaches to Electrolyte Abnormalities in Heart Failure.

    PubMed

    Grodin, Justin L

    2016-08-01

    Electrolyte abnormalities are common in heart failure and can arise from a variety of etiologies. Neurohormonal activation from ventricular dysfunction, renal dysfunction, and heart failure medications can perturb electrolyte homeostasis which impact both heart failure-related morbidity and mortality. These include disturbances in serum sodium, chloride, acid-base, and potassium homeostasis. Pharmacological treatments differ for each electrolyte abnormality and vary from older, established treatments like the vaptans or acetazolamide, to experimental or theoretical treatments like hypertonic saline or urea, or to newer, novel agents like the potassium binders: patiromer and zirconium cyclosilicate. Pharmacologic approaches range from limiting electrolyte intake or directly repleting the electrolyte, to blocking or promoting their resorption, and to neurohormonal antagonism. Because of the prevalence and clinical impact of electrolyte abnormalities, understanding both the older and newer therapeutic options is and will continue to be necessity for the management of heart failure. PMID:27278221

  17. [Quantitative estimation of connection of the heart rate rhythm with motor activity in rat fetuses].

    PubMed

    Vdovichenko, N D; Timofeeva, O P; Bursian, A V

    2014-01-01

    In rat fetuses at E17-20 with preserved placental circulation with use of mathematical analysis there were revealed value and character of connections of slow wave oscillations of the heart rhythm with motor activity for 30 min of observation. In the software "PowerGraph 3.3.8", normalization and filtration of the studied signals were performed at three frequency diapasons: D1 - 0.02-0.2 Hz (5-50 s), D2 - 0.0083-0.02 Hz (50 s-2 min), and D3 - 0.0017-0.0083 Hz (2-10 min). The EMG curves filtrated by diapasons or piezograms were compared with periodograms in the corresponding diapasons of the heart rhythm variations. In the software "Origin 8.0", quantitative estimation of the degree of intersystemic interrelations for each frequency diapason was performed by Pearson correlation of coefficient, by the correlation connection value, and by the time shift of maximum of cross-correlation function. It has been established that in the frequency D1, regardless of age, the connection of heart rhythm oscillations with motor activity is expressed weakly. In the frequency diapason D2, the connection in most cases is located in the zone of weak and moderate correlations. In the multiminute diapason (D3), the connection is more pronounced. The number of animals that have a significant value of the correlation connection rises. The fetal MA fires in the decasecond diapason in all age groups are accompanied by short-time decelerations of the heart rhythms. In the minute diapason, there is observed a transition from positive connections at E17 and E18 to the negative ones at E19-20. Results of the study are considered in association with age-related changes of ratios of positive and negative oscillations of the heart rhythm change depending on the character of motor activity. PMID:25486813

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

    PubMed Central

    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 (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. PMID:24454283

  19. Delay-correlation landscape reveals characteristic time delays of brain rhythms and heart interactions.

    PubMed

    Lin, Aijing; Liu, Kang K L; Bartsch, Ronny P; Ivanov, Plamen Ch

    2016-05-13

    Within the framework of 'Network Physiology', we ask a fundamental question of how modulations in cardiac dynamics emerge from networked brain-heart interactions. We propose a generalized time-delay approach to identify and quantify dynamical interactions between physiologically relevant brain rhythms and the heart rate. We perform empirical analysis of synchronized continuous EEG and ECG recordings from 34 healthy subjects during night-time sleep. For each pair of brain rhythm and heart interaction, we construct a delay-correlation landscape (DCL) that characterizes how individual brain rhythms are coupled to the heart rate, and how modulations in brain and cardiac dynamics are coordinated in time. We uncover characteristic time delays and an ensemble of specific profiles for the probability distribution of time delays that underly brain-heart interactions. These profiles are consistently observed in all subjects, indicating a universal pattern. Tracking the evolution of DCL across different sleep stages, we find that the ensemble of time-delay profiles changes from one physiologic state to another, indicating a strong association with physiologic state and function. The reported observations provide new insights on neurophysiological regulation of cardiac dynamics, with potential for broad clinical applications. The presented approach allows one to simultaneously capture key elements of dynamic interactions, including characteristic time delays and their time evolution, and can be applied to a range of coupled dynamical systems. PMID:27044991

  20. Autonomous detection of heart sound abnormalities using an auscultation jacket.

    PubMed

    Visagie, C; Scheffer, C; Lubbe, W W; Doubell, A F

    2009-12-01

    This paper presents a study using an auscultation jacket with embedded electronic stethoscopes, and a software classification system capable of differentiating between normal and certain auscultatory abnormalities. The aim of the study is to demonstrate the potential of such a system for semi-automated diagnosis for underserved locations, for instance in rural areas or in developing countries where patients far outnumber the available medical personnel. Using an "auscultation jacket", synchronous data was recorded at multiple chest locations on 31 healthy volunteers and 21 patients with heart pathologies. Electrocardiograms (ECGs) were also recorded simultaneously with phonocardiographic data. Features related to heart pathologies were extracted from the signals and used as input to a feed-forward artificial neural network. The system is able to classify between normal and certain abnormal heart sounds with a sensitivity of 84% and a specificity of 86%. Though the number of training and testing samples presented are limited, the system performed well in differentiating between normal and abnormal heart sounds in the given database of available recordings. The results of this study demonstrate the potential of such a system to be used as a fast and cost-effective screening tool for heart pathologies. PMID:20169844

  1. [Structure peculiarities, conditions and factors preceding the development of heart rhythm disorder in Chernobyl cleanup workers].

    PubMed

    Khomaziuk, I M; Zlatohors'ka, Zh M; Kursina, N V; Nastina, O M; Sydorenko, H V

    2008-01-01

    3595 participants of liquidation of consequences of Chernobyl accident (LCA) have been follow-upped since 1986. Structure and factors prior the development of heart rhythm derangements, results of physical examination, tonometry, ECG daily monitoring with taking into account the variability of heart rhythm, data of echocardiography with Doppler analysis have been established in 742 patients. Extrasystolic arrhythmia (50.8%) and atrium fibrillation prevailed in clinical structure of clinical structure of heart rhythm disorders (HRD). Etiological factors of HRD in 91.1% of cases were ischemic heart disease (IHD), hypertension and especially their combination, in 4.6%--other disorders, 4.6%--idiopathic HRD. It is possible to address special significance among factors before the development of HRD the following ones: participation in LCA since 1986, shift team work, ionizing radiation > or = 25 c3B, negative thoughts and memory about these events, from style of living--smoking habit, professional contact with xenobiotics, increased levels of arterial pressure, cholesterin, body weight index. Especial attention should be given to as predictors of the development of HRD -increased myocardium weight index > or = 170 gr/M2, duration of common and painless myocardial ischemia, basal frequency of heart rhythm > or = 75 b./m. It was established reliable relation between ventricular extrasystole and decreased of common BCP (r = -0.57; P < 0.05), spectrum power, (r = -0.52; P < 0.05), correlation disorder between its components. It is logical there was influence caused by combination of factors arised in connection with Chernobyl accident, life style and structural and functional changes of myocardium, hypertension and ischemic heart disease which are often found in Chernobyl disaster fighters. PMID:19145816

  2. Masking of the circadian rhythms of heart rate and core temperature by the rest-activity cycle in man

    NASA Technical Reports Server (NTRS)

    Gander, Philippa H.; Connell, Linda J.; Graeber, R. Curtis

    1986-01-01

    Experiments were conducted to estimate the magnitude of the masking effect produced in humans by alternate periods of physical activity and rest or sleep on the circadian rhythms of heart rate and core temperature. The heart rate, rectal temperature, and nondominant wrist activity were monitored in 12 male subjects during 6 days of normal routine at home and during 6 days of controlled bed-rest regimen. The comparisons of averaged waveforms for the activity, heart rate, and temperature indicated that about 45 percent of the range of the circadian heart rate rhythm during normal routine and about 14 percent of the range of the circadian temperature rhythm were attributable to the effects of activity. The smaller effect of activity on the temperature rhythm may be partially attributable to the fact that core temperature is being more rigorously conserved than heart rate, at least during moderate exercise.

  3. Electrocardiographic imaging of heart rhythm disorders: from bench to bedside.

    PubMed

    Rudy, Yoram; Lindsay, Bruce D

    2015-03-01

    Noninvasive electrocardiographic imaging (ECGI; also called ECG mapping) can reconstruct potentials, electrograms, activation sequences, and repolarization patterns on the epicardial surface of the heart with high resolution. ECGI can possibly be used to quantify synchrony, identify potential responders/nonresponders to cardiac resynchronization therapy, and guide electrode placement for effective resynchronization therapy. This article provides a brief description of the ECGI procedure and selected previously published examples of its application in important clinical conditions, including heart failure, cardiac resynchronization therapy, atrial arrhythmias, and ventricular tachycardia. PMID:25722753

  4. Effect of suprachiasmatic lesions on diurnal heart rate rhythm in the rat

    NASA Technical Reports Server (NTRS)

    Saleh, M. A.; Winget, C. M.

    1977-01-01

    Heart rate and locomotor activity of rats kept under 12L/12D illumination regimen were recorded every six minutes for ten days using implantable radio transmitters. Some of the rats then received bilateral RF lesions into the suprachiasmatic nucleus (SCN). Control sham operations were performed on the rest of the animals. After recovery from surgery, recording of heart rate and locomotor activity was continued for ten days. SCN-lesioned rats showed no significant diurnal fluctuation in heart rate, while normal and sham-operated rats showed the normal diurnal rhythm in that function. The arrhythmic diurnal heart-rate pattern of SCN rats appeared to be correlated with their sporadic activity pattern. The integrity of the suprachiasmatic nucleus is therefore necessary for the generation and/or expression of diurnal rhythmicity in heart rate in the rat.

  5. Computation of nonlinear parameters of heart rhythm using short time ECG segments.

    PubMed

    Koichubekov, Berik; Korshukov, Ilya; Omarbekova, Nazgul; Riklefs, Viktor; Sorokina, Marina; Mkhitaryan, Xenia

    2015-01-01

    We propose the method to compute the nonlinear parameters of heart rhythm (correlation dimension D₂ and correlation entropy K₂) using 5-minute ECG recordings preferred for screening of population. Conversion of RR intervals' time series into continuous function x(t) allows getting the new time series with different sampling rate dt. It has been shown that for all dt (250, 200, 125, and 100 ms) the cross-plots of D₂ and K₂ against embedding dimension m for phase-space reconstruction start to level off at m = 9. The sample size N at different sampling rates varied from 1200 at dt = 250 ms to 3000 at dt = 100 ms. Along with, the D₂ and K₂ means were not statistically different; that is, the sampling rate did not influence the results. We tested the feasibility of the method in two models: nonlinear heart rhythm dynamics in different states of autonomous nervous system and age-related characteristics of nonlinear parameters. According to the acquired data, the heart rhythm is more complex in childhood and adolescence with more influential parasympathetic influence against the background of elevated activity of sympathetic autonomous nervous system. PMID:25688286

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

    OBJECTIVE--To investigate the alterations in autonomic control of heart rate at high altitude and to test the hypothesis that hypoxaemic stress during exposure to high altitude induces non-linear, periodic heart rate oscillations, similar to those seen in heart failure and the sleep apnoea syndrome. SUBJECTS--11 healthy subjects aged 24-64. MAIN OUTCOME MEASURES--24 hour ambulatory electrocardiogram records obtained at baseline (1524 m) and at 4700 m. Simultaneous heart rate and respiratory dynamics during 2.5 hours of sleep by fast Fourier transform analysis of beat to beat heart rate and of an electrocardiographically derived respiration signal. RESULTS--All subjects had resting hypoxaemia at high altitude, with an average oxyhaemoglobin saturation of 81% (5%). There was no significant change in mean heart rate, but low frequency (0.01-0.05 Hz) spectral power was increased (P < 0.01) at high altitude. Time series analysis showed a complex range of non-linear sinus rhythm dynamics. Striking low frequency (0.04-0.06 Hz) heart rate oscillations were observed during sleep in eight subjects at high altitude. Analysis of the electrocardiographically derived respiration signal indicated that these heart rate oscillations correlated with low frequency respiratory oscillations. CONCLUSIONS--These data suggest (a) that increased low frequency power during high altitude exposure is not simply attributable to increased sympathetic modulation of heart rate, but relates to distinctive cardiopulmonary oscillations at approximately 0.05 Hz and (b) that the emergence of periodic heart rate oscillations at high altitude is consistent with an unstable cardiopulmonary control system that may develop on acute exposure to hypoxaemic stress.

  8. Stroke and bleeding risk evaluation in atrial fibrillation: results of the European heart rhythm association survey.

    PubMed

    Larsen, Torben Bjerregaard; Potpara, Tatjana; Dagres, Nikolaos; Pison, Laurent; Estner, Heidi; Blomström-Lundqvist, Carina

    2014-05-01

    The aim of this European Heart Rhythm Association (EHRA) survey was to assess clinical practice in relation to stroke and bleeding risk evaluation in atrial fibrillation, particularly regarding the use of risk evaluation schemes, among members of the EHRA electrophysiology (EP) research network. In this EP Wire survey, we have provided some insights into current practice in Europe for the use of these risk assessment schemes. There were some obvious practice differences. However, reassuring information on current practice in Europe was evident, but more focus on renal function is warranted, especially facing the fact that novel oral anticoagulants are used for antithrombotic therapy. PMID:24798958

  9. Clinical management of arrhythmias in elderly patients: results of the European Heart Rhythm Association survey.

    PubMed

    Chen, Jian; Hocini, Mélèze; Larsen, Torben Bjerregaard; Proclemer, Alessandro; Sciaraffia, Elena; Blomström-Lundqvist, Carina

    2015-02-01

    The purpose of this survey was to assess clinical practice in management of cardiac arrhythmias in elderly patients (age ≥75 years) in the European countries. The data are based on an electronic questionnaire sent to the European Heart Rhythm Association Research Network members. Responses were received from 50 centres in 20 countries. The results of the survey have shown that management of cardiac arrhythmias is generally in accordance with the guidelines and consensus recommendations on management of cardiac arrhythmias, although there are some areas of variation, especially on age limit and exclusion of elderly patients for anticoagulation, ablation, and device therapy. PMID:25634939

  10. Alignment of R-R interval signals using the circadian heart rate rhythm.

    PubMed

    Gayraud, Nathalie T H; Manis, George

    2015-01-01

    R-R interval signals that come from different subjects are regularly aligned and averaged according to the horological starting time of the recordings. We argue that the horological time is a faulty alignment criterion and provide evidence in the form of a new alignment method. Our main motivation is that the human heart rate (HR) rhythm follows a circadian cycle, whose pattern can vary among different classes of people. We propose two novel alignment algorithms that consider the HR circadian rhythm, the Puzzle Piece Alignment Algorithm (PPA) and the Event Based Alignment Algorithm (EBA). First, we convert the R-R interval signal into a series of time windows and compute the mean HR per window. Then our algorithms search for matching circadian patterns to align the signals. We conduct experiments using R-R interval signals extracted from two databases in the Physionet Data Bank. Both algorithms are able to align the signals with respect to the circadian rhythmicity of HR. Furthermore, our findings confirm the presence of more than one pattern in the circadian HR rhythm. We suggest an automatic classification of signals according to the three most prominent patterns. PMID:26737009

  11. Who Needs Heart Surgery?

    MedlinePlus

    ... disease (CHD) Fix heart valves that don't work well Control abnormal heart rhythms Place medical devices Replace a damaged heart with a healthy one If other treatments—such as lifestyle changes, medicines, and medical ... surgeon will work with you to decide whether you need heart ...

  12. Low dimensional model of heart rhythm dynamics as a tool for diagnosing the anaerobic threshold

    SciTech Connect

    Anosov, O.L.; Butkovskii, O.Y.; Kadtke, J.; Kravtsov, Y.A.

    1997-05-01

    We report preliminary results on describing the dependence of the heart rhythm variability on the stress level by using qualitative, low dimensional models. The reconstruction of macroscopic heart models yielding cardio cycles (RR-intervals) duration was based on actual clinical data. Our results show that the coefficients of the low dimensional models are sensitive to metabolic changes. In particular, at the transition between aerobic and aerobic-anaerobic metabolism, there are pronounced extrema in the functional dependence of the coefficients on the stress level. This strong sensitivity can be used to design an easy indirect method for determining the anaerobic threshold. This method could replace costly and invasive traditional methods such as gas analysis and blood tests. {copyright} {ital 1997 American Institute of Physics.}

  13. Proceedings from Heart Rhythm Society's emerging technologies forum, Boston, MA, May 12, 2015.

    PubMed

    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

    2016-02-01

    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 convened a forum of stakeholders in medical device innovation in conjunction with the 2015 Heart Rhythm Society Annual Scientific Sessions. The forum facilitated open discussion on 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 US Food and Drug Administration and Centers for Medicare & Medicaid Services 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 policymakers. PMID:26801401

  14. No Statins Before Heart Surgery, Study Suggests

    MedlinePlus

    ... harm, a new study suggests. In that setting, Crestor (rosuvastatin) did not prevent either the abnormal heart rhythm ... who were having elective heart surgery to take Crestor or a placebo before surgery. The researchers found ...

  15. Metabolic abnormalities of the heart in type II diabetes.

    PubMed

    Amaral, Nelson; Okonko, Darlington O

    2015-07-01

    Type 2 diabetes mellitus escalates the risk of heart failure partly via its ability to induce a cardiomyopathic state that is independent of coronary artery disease and hypertension. Although the pathogenesis of diabetic cardiomyopathy has yet to be fully elucidated, aberrations in cardiac substrate metabolism and energetics are thought to be key drivers. These aberrations include excessive fatty acid utilisation and storage, suppressed glucose oxidation and impaired mitochondrial oxidative phosphorylation. An appreciation of how these abnormalities arise and synergise to promote adverse cardiac remodelling is critical to their effective amelioration. This review focuses on disturbances in myocardial fuel (fatty acids and glucose) flux and energetics in type 2 diabetes, how these disturbances relate to the development of diabetic cardiomyopathy and the potential therapeutic agents that could be used to correct them. PMID:25941161

  16. Improvement of Circadian Rhythm of Heart Rate Variability by Eurythmy Therapy Training

    PubMed Central

    Seifert, Georg; Kanitz, Jenny-Lena; Pretzer, Kim; Henze, Günter; Witt, Katharina; Reulecke, Sina; Voss, Andreas

    2013-01-01

    Background. Impairment of circadian rhythm is associated with various clinical problems. It not only has a negative impact on quality of life but can also be associated with a significantly poorer prognosis. Eurythmy therapy (EYT) is an anthroposophic movement therapy aimed at reducing fatigue symptoms and stress levels. Objective. This analysis of healthy subjects was conducted to examine whether the improvement in fatigue symptoms was accompanied by improvements in the circadian rhythm of heart rate variability (HRV). Design. Twenty-three women performed 10 hours of EYT over six weeks. Electrocardiograms (ECGs) were recorded before and after the EYT trial. HRV was quantified by parameters of the frequency and time domains and the nonlinear parameters of symbolic dynamics. Results. The day-night contrast with predominance of vagal activity at night becomes more pronounced after the EYT training, and with decreased Ultralow and very low frequencies, the HRV shows evidence of calmer sleep. During the night, the complexity of the HRV is significantly increased indicated by nonlinear parameters. Conclusion. The analysis of the circadian patterns of cardiophysiological parameters before and after EYT shows significant improvements in HRV in terms of greater day-night contrast caused by an increase of vagal activity and calmer and more complex HRV patterns during sleep. PMID:23533496

  17. [Individual peculiarities of adaptation to long-term space flights: 24-hour heart rhythm monitoring

    NASA Technical Reports Server (NTRS)

    Baevskii, R. M.; Bogomolov, V. V.; Gol'dberger, A. L.; Nikulina, G. A.; Charl'z, D. B.; Goldberger, A. L. (Principal Investigator); Charles, J. B. (Principal Investigator)

    2000-01-01

    Presented are results of studying 24-hr variability of the cardiac rhythm which characterizes individual difference in reactions of two crew members to the same set of stresses during a 115-day MIR mission. Spacelab (USA) cardiorecorders were used. Data of monitoring revealed significantly different baseline health statuses of the cosmonauts. These functional differences were also observed in the mission. In one of the cosmonauts, the cardiac regulation changed over to a more economic functioning with the autonomous balance shifted towards enhanced sympathetic activity. After 2-3 months on mission he had almost recovered pre-launch level of regulation. In the other, the regulatory system was appreciably strained at the beginning of the mission as compared with preflight baseline. Later on, on flight months 2-3, this strain kept growing till a drastic depletion of the functional reserve. On return to Earth, this was manifested by a strong stress reaction with a sharp decline in power of high-frequency and grow in power of very low frequency components of the heart rhythm. The data suggest that adaptation to space flight and reactions in the readaptation period are dependent on initial health status of crew members, and functional reserve.

  18. Circadian rhythms (temperature, heart rate, vigilance, mood) of short and long sleepers: effects of sleep deprivation.

    PubMed

    Benoit, O; Foret, J; Merle, B; Reinberg, A

    1981-01-01

    Seven long sleepers (LS) (sleep greater than or equal to 9 h) and seven short sleepers (SS) (sleep less than or equal to 7 h), aged 20 to 23 years, were selected among medical students. They measured their axillary temperature (T), heart rate (HR) and self-estimated their vigilance (V) and mood (M) every 4 h from awakening to bed time during a ten-day control span and during the two sleep deprived nights. Polygraphic sleep recordings were performed on 3 control days and recovery from 24 h (day sleep) or 36 h (night sleep) sleep deprivations. For the 4 variables (T, HR, V and M), group circadian patterns were analyzed by means of the cosinor method for the control span and after both types of sleep deprivation. The acrophases of the 4 variables clustered more in LS than in SS. The acrophases of V and M were found to be more closely related to the sleep/wake rhythm than those of T and HR. Sleep deprivation resulted in a large change of the circadian rhythms in LS but had little effect in SS as indicated by the non detection of most acrophases in LS and the persistence of such acrophases in SS. This difference might be explained by the large interindividual variability of changes induced by the sleep deprivation in LS. Moreover, day sleep recovery was more disturbed in LS than in SS. PMID:7327054

  19. Management of patients with ventricular tachycardia in Europe: results of the European Heart Rhythm Association survey.

    PubMed

    Chen, Jian; Todd, Derick M; Proclemer, Alessandro; Sciaraffia, Elena; Estner, Heidi L; Broadhurst, Paul; Blomström-Lundqvist, Carina

    2015-08-01

    The purpose of this European Heart Rhythm Association (EHRA) survey was to assess clinical practice in the management of ventricular tachycardia (VT). The data are based on an electronic questionnaire sent to the members of the EHRA Research Network. Responses were received from 31 centres in 16 countries. The results of the survey show that the management of VT is in general in accordance with guidelines. Antiarrhythmic drugs are still frequently used for VT treatment. In patients at high risk of sudden cardiac death, an implantable cardioverter-defibrillator is routinely recommended, while the treatment options vary for patients with moderate or low risk. A discreet attitude is adopted for catheter ablation in high-risk patients as demonstrated by a relatively low rate of catheter ablation. PMID:26273104

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

    NASA Technical Reports Server (NTRS)

    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.

  1. Defibrillation testing at the time of implantable cardioverter defibrillator implantation: results of the European Heart Rhythm Association survey.

    PubMed

    Morgan, John M; Marinskis, Germanas

    2011-04-01

    This survey assesses the current practices of testing defibrillation function at the time of the first implanted cardioverter defibrillator placement. Responses have been collected from 57 European heart rhythm management centres. The results of the survey show an extraordinary inconsistency in the approaches to defibrillation testing (19.3% of responders report no testing at the time of implantation). A policy statement on this topic would help to improve patient care and unify the procedure according to evidence based data. PMID:21447521

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

    NASA Technical Reports Server (NTRS)

    Scheuring, Richard A.; Hamilton, D.; Jones, J. A.; Alexander, D.

    2008-01-01

    Currently there are several physiological monitoring requirements for Extravehicular Activity (EVA) in the Human-Systems Interface Requirements (HSIR) document, including continuous heart rhythm monitoring. However, it is not known whether heart rhythm monitoring in the lunar surface space suit is a necessary capability for lunar surface operations or in launch/landing suit the event of a cabin depressurization enroute to or from the moon. Methods: Current US astronaut corps demographic information was provided to an expert panel of cardiovascular medicine experts, including specialists in electrophysiology, exercise physiology, interventional cardiology and arrhythmia. This information included averages for male/female age, body mass index (BMI), blood pressure, cholesterol, inflammatory markers, echocardiogram, ranges for coronary artery calcium (CAC) scores for long duration astronauts, and ranges for heart rate (HR) and metabolic (MET) rates obtained during microgravity and lunar EVA. Results: The panel determined that no uncontrolled hazard was likely to occur in the suit during lunar surface or contingency microgravity ops that would require ECG monitoring in the highly screened US astronaut population. However having the capability for rhythm monitoring inside the vehicle (IVA) was considered critical to manage an astronaut in distress. Discussion: Heart rate (HR) monitoring alone allows effective monitoring of astronaut health and function. Consequently, electrocardiographic (ECG) monitoring capability as a clinical tool is not essential in the lunar or launch/landing space suit. However, the panel considered that rhythm monitoring could be useful in certain clinical situations, it was not considered required for safe operations. Also, lunar vehicles should be required to have ECG monitoring capability with a minimum of 5-lead ECG (derived 12- lead) for IVA medical assessments.

  3. Detection and significance of a discrete very low frequency rhythm in RR interval variability in chronic congestive heart failure.

    PubMed

    Ponikowski, P; Chua, T P; Amadi, A A; Piepoli, M; Harrington, D; Volterrani, M; Colombo, R; Mazzuero, G; Giordano, A; Coats, A J

    1996-06-15

    Although in advanced chronic congestive heart failure (CHF) very low frequency (< 0.04 Hz, VLF) oscillations are prominent, the clinical importance and the physiologic basis of these rhythms have not been elucidated. To investigate the physiologic determinants of the VLF rhythms in RR interval variability, we studied 36 patients with stable, moderate to severe CHF (33 men, age: 58 +/- 8 years, ejection fraction 25 +/- 10%, peak oxygen consumption 18.1 +/- 4.6 ml/kg/min) and 12 age- and sex-matched controls using autoregressive spectral analysis of RR interval, blood pressure, and respiratory signals during controlled conditions. We quantified low frequency (LF) (0.04 to 0.15 Hz), high frequency (HF) (0.15 to 0.40 Hz), VLF, and total power (0 to 0.5 Hz), and calculated the coherence between systolic blood pressure and RR interval variability within each band. Peripheral chemosensitivity was assessed by the ventilatory response to hypoxia using transient inhalation of pure nitrogen. The influence of transient inactivation of peripheral chemoreceptors on the VLF rhythm was investigated by exposing 6 patients to hyperoxic (60% oxygen) conditions for 20 minutes. Twenty-three patients (64%) with CHF, but no controls, had a discrete VLF rhythm (0.019 +/- 0.008 Hz) in RR variability. The presence of VLF rhythm was not related to any difference in clinical parameters (etiology, New York Heart Association class, ejection fraction, oxygen uptake) but rather to a different pattern in RR interval and blood pressure variability: lower LF power (2.8 +/- 1.6 ms2 natural logarithm [ln]) compared either to patients without VLF (4.0 +/- 1.3 ms2 ln) or to controls (5.9 +/- 0.7 ms2 ln), higher percentage of power within VLF band (86.3 +/- 8.3% vs 77.5 +/- 7.9% and 61.5 +/- 14.1%) and a markedly impaired coherence between RR interval and systolic blood pressure variability within the LF band (0.26 +/- 0.10 vs 0.42 +/- 0.18 and 0.63 +/- 0.15, in patients with vs without VLF peak and

  4. Current ablation techniques for persistent atrial fibrillation: results of the European Heart Rhythm Association Survey.

    PubMed

    Dagres, Nikolaos; Bongiorni, Maria Grazia; Larsen, Torben Bjerregaard; Hernandez-Madrid, Antonio; Pison, Laurent; Blomström-Lundqvist, Carina

    2015-10-01

    The aim of this survey was to provide insight into current practice regarding ablation of persistent atrial fibrillation (AF) among members of the European Heart Rhythm Association electrophysiology research network. Thirty centres responded to the survey. The main ablation technique for first-time ablation was stand-alone pulmonary vein isolation (PVI): in 67% of the centres for persistent but not long-standing AF and in 37% of the centres for long-standing persistent AF as well. Other applied techniques were ablation of fractionated electrograms, placement of linear lesions, stepwise approach until AF termination, and substrate mapping and isolation of low-voltage areas. However, the percentage of centres applying these techniques during first ablation did not exceed 25% for any technique. When stand-alone PVI was performed in patients with persistent but not long-standing AF, the majority (80%) of the centres used an irrigated radiofrequency ablation catheter whereas 20% of the respondents used the cryoballoon. Similar results were reported for ablation of long-standing persistent AF (radiofrequency 90%, cryoballoon 10%). Neither rotor mapping nor one-shot ablation tools were used as the main first-time ablation methods. Systematic search for non-pulmonary vein triggers was performed only in 10% of the centres. Most common 1-year success rate off antiarrhythmic drugs was 50-60%. Only 27% of the centres knew their 5-year results. In conclusion, patients with persistent AF represent a significant proportion of AF patients undergoing ablation. There is a shift towards stand-alone PVI being the primary choice in many centres for first-time ablation in these patients. The wide variation in the use of additional techniques and in the choice of endpoints reflects the uncertainties and lack of guidance regarding the most optimal approach. Procedural success rates are modest and long-term outcomes are unknown in most centres. PMID:26498718

  5. Current periprocedural management of ablation for atrial fibrillation in Europe: results of the European Heart Rhythm Association survey.

    PubMed

    Chen, Jian; Todd, Derick M; Hocini, Mélèze; Larsen, Torben Bjerregaard; Bongiorni, Maria Grazia; Blomström-Lundqvist, Carina

    2014-03-01

    The purpose of this EP Wire survey was to assess clinical practice in periprocedural management of atrial fibrillation ablation. This survey is based on an electronic questionnaire sent to the European Heart Rhythm Association Research Network members. Responses were received from 78 centres in 20 countries. The results of the survey have shown that periprocedural management is generally in accordance with guidelines and consensus recommendations on ablation for atrial fibrillation ablation, although there are some areas of variation. Differences between high- and low-volume centres are observed with respect to patient selection, antiarrhythmic drug management, and heparin bridging. PMID:24569891

  6. Current practice for diagnosis and management of silent atrial fibrillation: results of the European Heart Rhythm Association survey.

    PubMed

    Dobreanu, Dan; Svendsen, Jesper Hastrup; Lewalter, Thorsten; Hernández-Madrid, Antonio; Lip, Gregory Y H; Blomström-Lundqvist, Carina

    2013-08-01

    Although it is well known that silent atrial fibrillation (AF) is associated with morbidity and mortality rates similar to those of symptomatic AF, no specific strategy for screening and management of this form of AF has been advocated. The purpose of this survey was to identify current practices for the diagnosis and management of silent AF. This survey is based on an electronic questionnaire sent to the European Heart Rhythm Association Research Network partners. Responses were received from 33 centres in 16 countries. The preferred screening methods for silent AF in patients with rhythm control by pharmacological therapy was 12-lead electrocardiogram (ECG) at outpatient visits (31.3%) and periodical 24 h Holter ECG recordings (34.4%), while after pulmonary vein isolation the corresponding figures were 6.3 and 65.6%, respectively. No consensus has been reached concerning the therapeutic approach for such patients. Most responders preferred rate control over rhythm control in patients with silent AF, although some favoured pulmonary vein isolation in young patients. However, oral anticoagulant therapy in patients at high thromboembolic risk was considered mandatory by most, provided that at least one episode of silent AF was documented, without recommending further investigations. The results of this survey have confirmed that there is currently no consensus regarding the screening and management of patients with silent AF and that clinical practice is not always consistent with the few existing evidence-based recommendations. PMID:23878150

  7. Increase in the embedding dimension in the heart rate variability associated with left ventricular abnormalities

    NASA Astrophysics Data System (ADS)

    Andrés, D. S.; Irurzun, I. M.; Mitelman, J.; Mola, E. E.

    2006-10-01

    In the present study, the authors report evidence that the existence of premature ventricular contractions increases the embedding dimension of the cardiac dynamics. They also analyze patients with congestive heart failure, a severe clinical condition associated with abnormal left ventricular function. Results also show an increase in the embedding dimension of the heart rate variability. They used electrocardiograms collected by themselves with quality standards that make them comparable with other databases.

  8. Diagnosis and management of patients with inherited arrhythmia syndromes in Europe: results of the European Heart Rhythm Association Survey.

    PubMed

    Hocini, Mélèze; Pison, Laurent; Proclemer, Alessandro; Larsen, Torben Bjerregaard; Madrid, Antonio; Blomström-Lundqvist, Carina

    2014-04-01

    Inherited arrhythmia disorders associated with structurally normal heart (i.e. long and short QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, early repolarization syndrome, idiopathic ventricular fibrillation) cause 10% of 1.1 million sudden deaths in Europe and the USA. The purpose of this European Heart Rhythm Association (EHRA) electrophysiology wire survey was to assess the European clinical practice adopted for the diagnosis and management of these disorders. The survey was based on an electronic questionnaire sent out to the EHRA Research Network centres. Responses were received from 50 centres in 23 countries. The results of the survey show that inherited arrhythmia syndromes have a relatively low burden and are diagnosed and managed in accordance with the current guidelines. However, more than 50% of centres do not participate in any existing registry underlining the need for establishing a pan-European registry of these disorders. PMID:24711616

  9. Personnel, equipment, and facilities for electrophysiological and catheter ablation procedures in Europe: results of the European Heart Rhythm Association Survey.

    PubMed

    Estner, Heidi L; Chen, Jian; Potpara, Tatjana; Proclemer, Alessandro; Todd, Derick; Blomström-Lundqvist, Carina

    2014-07-01

    Clinical electrophysiology (EP) and catheter ablation of arrhythmias are rapidly evolving in recent years. More than 50 000 catheter ablations are performed every year in Europe. Emerging indications, an increasing number of procedures, and an expected high quality require national and international standards as well as trained specialists. The purpose of this European Heart Rhythm Association (EHRA) survey was to assess the practice of requirements for EP personnel, equipment, and facilities in Europe. Responses to the questionnaire were received from 52 members of the EHRA research network. The survey involved high-, medium-, and low-volume EP centres, performing >400, 100-399, and under 100 implants per year, respectively. The following topics were explored: (i) EP personnel issues including balance between female and male operators, responsibilities within the EP department, age profiles, role and training of fellows, and EP nurses, (ii) the equipments available in the EP laboratories, (iii) source of patient referrals, and (iv) techniques used for ablation for different procedures including sedation, and peri-procedural use of anticoagulation and antibiotics. The survey reflects the current EP personnel situation characterized by a high training requirement and specialization. Arrhythmia sections are still most often part of cardiology departments and the head of cardiology is seldom a heart rhythm specialist. Currently, the vast majority of EP physicians are men, although in the subgroup of physicians younger than 40 years, the proportion of women is increasing. Uncertainty exists regarding peri-procedural anticoagulation, antibiotic prophylaxis, and the need for sedation during specific procedures. PMID:24966009

  10. Work-up and management of lone atrial fibrillation: results of the European Heart Rhythm Association Survey.

    PubMed

    Pison, Laurent; Hocini, Mélèze; Potpara, Tatjana S; Todd, Derick; Chen, Jian; Blomström-Lundqvist, Carina

    2014-10-01

    The purpose of this European Heart Rhythm Association (EHRA) survey was to explore the work-up and management of lone atrial fibrillation (AF) among the European centres. Thirty-two European centres, all members of the EHRA electrophysiology (EP) research network, responded to this survey and completed the list of questions. The prevalence of lone AF has been reported to be ≤10% by 19 (60%) of the participating centres. The presence of isolated left atrial enlargement and left ventricular diastolic dysfunction represent heart disease according to 50 and 84% of the centres, respectively, and exclude the diagnosis of lone AF. Fifty-nine per cent of responders do not routinely consider genetic testing in lone AF patients. The initial therapeutic approach in symptomatic paroxysmal lone AF is antiarrhythmic drug therapy as reported by 31 (97%) of the centres. Pulmonary vein isolation only is the first ablation strategy for patients with symptomatic persistent lone AF at 27 (84%) of the responding centres. Assessment for sleep apnoea, obesity, and intensive sports activity in lone AF is performed at 27 (84%) centres. In conclusion, this EP Wire survey confirms that the term 'lone AF' is still used in daily practice. The work-up typically includes screening for known risk factors but not genetic testing. The preferred management of paroxysmal lone AF is rhythm control with antiarrhythmic drugs, whereas pulmonary vein isolation is the first ablation strategy for the majority of patients with symptomatic persistent lone AF. PMID:25267359

  11. Personalized management of atrial fibrillation: Proceedings from the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association consensus conference.

    PubMed

    Kirchhof, Paulus; Breithardt, Günter; Aliot, Etienne; Al Khatib, Sana; Apostolakis, Stavros; Auricchio, Angelo; Bailleul, Christophe; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boersma, Lucas; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Casadei, Barbara; Clemens, Andreas; Crijns, Harry; Derwand, Roland; Dobrev, Dobromir; Ezekowitz, Michael; Fetsch, Thomas; Gerth, Andrea; Gillis, Anne; Gulizia, Michele; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Häusler, Karl Georg; Heidbüchel, Hein; Hernandez-Brichis, Jessica; Jais, Pierre; Kappenberger, Lukas; Kautzner, Joseph; Kim, Steven; Kuck, Karl-Heinz; Lane, Deirdre; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Moses, Gregory; Mueller, Markus; Münzel, Felix; Näbauer, Michael; Nielsen, Jens Cosedis; Oeff, Michael; Oto, Ali; Pieske, Burkert; Pisters, Ron; Potpara, Tatjana; Rasmussen, Lars; Ravens, Ursula; Reiffel, James; Richard-Lordereau, Isabelle; Schäfer, Herbert; Schotten, Ulrich; Stegink, Wim; Stein, Kenneth; Steinbeck, Gerhard; Szumowski, Lukasz; Tavazzi, Luigi; Themistoclakis, Sakis; Thomitzek, Karen; Van Gelder, Isabelle C; von Stritzky, Berndt; Vincent, Alphons; Werring, David; Willems, Stephan; Lip, Gregory Y H; Camm, A John

    2013-11-01

    The management of atrial fibrillation (AF) has seen marked changes in past years, with the introduction of new oral anticoagulants, new antiarrhythmic drugs, and the emergence of catheter ablation as a common intervention for rhythm control. Furthermore, new technologies enhance our ability to detect AF. Most clinical management decisions in AF patients can be based on validated parameters that encompass type of presentation, clinical factors, electrocardiogram analysis, and cardiac imaging. Despite these advances, patients with AF are still at increased risk for death, stroke, heart failure, and hospitalizations. During the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association (AFNET/EHRA) consensus conference, we identified the following opportunities to personalize management of AF in a better manner with a view to improve outcomes by integrating atrial morphology and damage, brain imaging, information on genetic predisposition, systemic or local inflammation, and markers for cardiac strain. Each of these promising avenues requires validation in the context of existing risk factors in patients. More importantly, a new taxonomy of AF may be needed based on the pathophysiological type of AF to allow personalized management of AF to come to full fruition. Continued translational research efforts are needed to personalize management of this prevalent disease in a better manner. All the efforts are expected to improve the management of patients with AF based on personalized therapy. PMID:23981824

  12. Case report of an unusual heart abnormality in Rainbow trout (Oncorhynchus mykiss)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An unusual heart abnormality in rainbow trout Oncorhynchus mykiss was recently observed. During the course of a standard hydrogen peroxide treatment (100 ppm) of production rainbow trout (mean weight, 2-3 g) affected with an external bacterial infection, a small percentage of fish exhibited morbidi...

  13. Teaching Recognition of Normal and Abnormal Heart Sounds Using Computer-Assisted Instruction

    ERIC Educational Resources Information Center

    Musselman, Eugene E.; Grimes, George M.

    1976-01-01

    The computer is being used in an innovative manner to teach the recognition of normal and abnormal canine heart sounds at the University of Chicago. Experience thus far indicates that the PLATO program resources allow the maximum development of the student's proficiency in auscultation. (Editor/LBH)

  14. Biological rhythms

    NASA Technical Reports Server (NTRS)

    Halberg, F.

    1975-01-01

    An overview is given of basic features of biological rhythms. The classification of periodic behavior of physical and psychological characteristics as circadian, circannual, diurnal, and ultradian is discussed, and the notion of relativistic time as it applies in biology is examined. Special attention is given to circadian rhythms which are dependent on the adrenocortical cycle. The need for adequate understanding of circadian variations in the basic physiological indicators of an individual (heart rate, body temperature, systolic and diastolic blood pressure, etc.) to ensure the effectiveness of prophylactic and therapeutic measures is stressed.

  15. An Algorithm for the Segmentation of Highly Abnormal Hearts Using a Generic Statistical Shape Model.

    PubMed

    Alba, Xenia; Pereanez, Marco; Hoogendoorn, Corne; Swift, Andrew J; Wild, Jim M; Frangi, Alejandro F; Lekadir, Karim

    2016-03-01

    Statistical shape models (SSMs) have been widely employed in cardiac image segmentation. However, in conditions that induce severe shape abnormality and remodeling, such as in the case of pulmonary hypertension (PH) or hypertrophic cardiomyopathy (HCM), a single SSM is rarely capable of capturing the anatomical variability in the extremes of the distribution. This work presents a new algorithm for the segmentation of severely abnormal hearts. The algorithm is highly flexible, as it does not require a priori knowledge of the involved pathology or any specific parameter tuning to be applied to the cardiac image under analysis. The fundamental idea is to approximate the gross effect of the abnormality with a virtual remodeling transformation between the patient-specific geometry and the average shape of the reference model (e.g., average normal morphology). To define this mapping, a set of landmark points are automatically identified during boundary point search, by estimating the reliability of the candidate points. With the obtained transformation, the feature points extracted from the patient image volume are then projected onto the space of the reference SSM, where the model is used to effectively constrain and guide the segmentation process. The extracted shape in the reference space is finally propagated back to the original image of the abnormal heart to obtain the final segmentation. Detailed validation with patients diagnosed with PH and HCM shows the robustness and flexibility of the technique for the segmentation of highly abnormal hearts of different pathologies. PMID:26552082

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

    PubMed Central

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

    2013-01-01

    Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate–increasing and heart rate–decreasing variants associate with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identify new therapeutic targets. PMID:23583979

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

    PubMed

    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 < .05, fold change >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. PMID:26251327

  18. Use of event recorders and loop recorders in clinical practice: results of the European Heart Rhythm Association Survey.

    PubMed

    Sciaraffia, Elena; Chen, Jian; Hocini, Meleze; Larsen, Torben Bierregaard; Potpara, Tatjana; Blomström-Lundqvist, Carina

    2014-09-01

    Several kinds of electrocardiogram monitoring systems are now available in the clinical practice. The aim of this European Heart Rhythm Association (EHRA) survey was to assess the use of different monitoring techniques in the evaluation of patients with unexplained syncope, palpitations, and in those with established diagnosis of atrial fibrillation. Forty-five centres in Europe answered the questionnaire and the majority (78%) were university hospitals. The answers showed a discrepancy between the recommended use of implantable loop recorders (ILRs) in patients with unexplained syncope and the use of this device in clinical practice. In most of the cases only a minority of patients (<20%) seemed to actually receive an ILR as a part of the diagnostic process in accordance to the current guidelines. Holter monitoring systems and external loop recorders seemed to be the preferred monitoring techniques both in patients with recurrent palpitations and in those with established diagnosis of atrial fibrillation. PMID:25172620

  19. How are arrhythmias detected by implanted cardiac devices managed in Europe? Results of the European Heart Rhythm Association Survey.

    PubMed

    Todd, Derick; Hernandez-Madrid, Antonio; Proclemer, Alessandro; Bongiorni, Maria Grazia; Estner, Heidi; Blomström-Lundqvist, Carina

    2015-09-01

    The management of arrhythmias detected by implantable cardiac devices can be challenging. There are no formal international guidelines to inform decision-making. The purpose of this European Heart Rhythm Association (EHRA) survey was to assess the management of various clinical scenarios among members of the EHRA electrophysiology research network. There were 49 responses to the questionnaire. The survey responses were mainly (81%) from medium-high volume device implanting centres, performing more than 200 total device implants per year. Clinical scenarios were described focusing on four key areas: the implantation of pacemakers for bradyarrhythmia detected on an implantable loop recorder (ILR), the management of patients with ventricular arrhythmia detected by an ILR or pacemaker, the management of atrial fibrillation in patients with pacemakers and cardiac resynchronization therapy devices and the management of ventricular tachycardia in patients with implantable cardioverter-defibrillators. PMID:26443791

  20. Current implantable cardioverter-defibrillator programming in Europe: the results of the European Heart Rhythm Association survey.

    PubMed

    Proclemer, Alessandro; Grazia Bongiorni, Maria; Etsner, Heidi; Todd, Derick; Sciaraffia, Elena; Blomström-Lundqvist, Carina

    2014-06-01

    The purpose of this European Heart Rhythm Association (EHRA) survey was to examine the current practice on the choice of implantable cardioverter-defibrillator (ICD) type, use of defibrillation testing, and ICD programming for detection and therapy of ventricular arrhythmias. In accordance with recent guidelines and the results of observational studies, the majority of EHRA research network centres reported a high utilization rate of dual-chamber ICDs in the presence of symptomatic and asymptomatic sinus node dysfunction, biventricular ICD in high-degree atrioventricular block and QRS duration <120 ms, and a limited use of defibrillation testing either in primary and secondary prevention settings. Activation of the long ventricular tachycardia (VT) detection window, slow VT zone, antitachycardia pacing before shock for slow and fast VT, and atrial tachyarrhythmia discrimination were considered useful in ICD programming for the majority of patients. PMID:24864305

  1. 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.

    PubMed

    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. PMID:26177817

  2. Effects of long-term microgravity exposure in space on circadian rhythms of heart rate variability.

    PubMed

    Yamamoto, Naomune; Otsuka, Kuniaki; Kubo, Yutaka; Hayashi, Mitsutoshi; Mizuno, Koh; Ohshima, Hiroshi; Mukai, Chiaki

    2015-04-01

    We evaluated their circadian rhythms using data from electrocardiographic records and examined the change in circadian period related to normal RR intervals for astronauts who completed a long-term (≥6-month) mission in space. The examinees were seven astronauts, five men and two women, from 2009 to 2010. Their mean ± SD age was 52.0 ± 4.2 years (47-59 yr). Each stayed in space for more than 160 days; their average length of stay was 172.6 ± 14.6 days (163-199 days). We conducted a 24-h Holter electrocardiography before launch (Pre), at one month after launch (DF1), at two months after launch (DF2), at two weeks before return (DF3), and at three months after landing (Post), comparing each index of frequency-domain analysis and 24-h biological rhythms of the NN intervals (normal RR intervals). Results show that the mean period of Normal Sinus (NN) intervals was within 24 ± 4 h at each examination. Inter-individual variability differed among the stages, being significantly smaller at DF3 (Pre versus DF1 versus DF3 versus Post = 22.36 ± 2.50 versus 25.46 ± 4.37 versus 22.46 ± 1.75 versus 26.16 ± 7.18 h, p < 0.0001). The HF component increased in 2 of 7 astronauts, whereas it decreased in 3 of 7 astronauts and 1 was remained almost unchanged at DF1. During DF3, about 6 months after their stay in space, the HF component of 5 of 7 astronauts recovered from the decrease after launch, with prominent improvement to over 20% in 3 astronauts. Although autonomic nervous functions and circadian rhythms were disturbed until one month had passed in space, well-scheduled sleep and wake rhythms and meal times served as synchronizers. PMID:25392280

  3. Non-coronary abnormalities of the left heart: CT angiography findings.

    PubMed

    Öztürk, Ersin; Kafadar, Cahit; Tutar, Süleyman; Bozlar, Uğur; Hagspiel, Klaus D

    2016-09-01

    Cardiac computed tomography (CT) is most commonly performed for the evaluation of the coronary arteries; however, non-coronary cardiac pathologies are frequently detected on these scans. In cases where magnetic resonance imaging cannot be used, cardiac CT can serve as the first-line imaging modality to evaluate many non-coronary cardiac pathologies. In this article, we discuss congenital non-coronary abnormalities of the left heart and their cardiac CT imaging features. PMID:27609435

  4. Alterations of the intercellular coupling protein, connexin-43, during ventricular fibrillation and sinus rhythm restoration demonstrated in male and female rat hearts: A pilot study

    PubMed Central

    Radošinská, Jana; Knezl, Vladimír; Benová, Tamara; Urban, L’ubomír; Tribulová, Narcis; Slezák, Ján

    2011-01-01

    Ventricular fibrillation (VF) is a life-threatening arrhythmia, whose occurrence precedes the development of myocardial arrhythmogenic substrate resulting from either chronic or acute pathophysiological conditions. The authors’ previous and current studies suggest that downregulated and/or heterogeneously distributed cell-to-cell coupling protein – connexin-43 (Cx43) – facilitates the development of malignant arrhythmias. It was hypothesized that VF itself deteriorates Cx43, and may hamper cardioversion into sinus rhythm. The purpose of the present study was to examine whether myocardial expression and the phosphorylated status of Cx43 is altered due to VF and during sinus rhythm restoration. Experiments were performed using 10-month-old male and female Wistar rats. Isolated Langendorff-mode-perfused rat hearts were subjected to the following events: basal condition, electrically induced VF lasting 2 min, electrically induced VF lasting 10 min, and sustained VF followed by spontaneous sinus rhythm restoration due to transient stop perfusion. The hearts were snap frozen at each event; ventricular tissue was sent for Cx43 immunoblotting using rabbit antiCx43 polyclonal antibody to detect phosphorylated (P-Cx43) as well as unphosphorylated (noP-Cx43) forms of Cx43, and mouse antiCx43 monoclonal antibody to detect noP-Cx43 only. Compared with basal conditions, total Cx43 expression did not change during experiments in either male or female rat hearts. However, P-Cx43 and the ratio of P-Cx43 to total Cx43 decreased significantly due to VF lasting 2 min and 10 min in male rat hearts only. In parallel, there was a significant increase in noP-Cx43 due to VF lasting 2 min and 10 min in male rat hearts only. Surprisingly, an enhancement of noP-Cx43 linked with suppression of P-Cx43 was detected during stop perfusion-induced termination of VF lasting 2 min, followed by sinus rhythm restoration in both male and female rat hearts. Sinus rhythm was not restored after 10

  5. Alterations of the intercellular coupling protein, connexin-43, during ventricular fibrillation and sinus rhythm restoration demonstrated in male and female rat hearts: A pilot study.

    PubMed

    Radošinská, Jana; Knezl, Vladimír; Benová, Tamara; Urban, L'ubomír; Tribulová, Narcis; Slezák, Ján

    2011-01-01

    Ventricular fibrillation (VF) is a life-threatening arrhythmia, whose occurrence precedes the development of myocardial arrhythmogenic substrate resulting from either chronic or acute pathophysiological conditions. The authors' previous and current studies suggest that downregulated and/or heterogeneously distributed cell-to-cell coupling protein - connexin-43 (Cx43) - facilitates the development of malignant arrhythmias. It was hypothesized that VF itself deteriorates Cx43, and may hamper cardioversion into sinus rhythm. The purpose of the present study was to examine whether myocardial expression and the phosphorylated status of Cx43 is altered due to VF and during sinus rhythm restoration. Experiments were performed using 10-month-old male and female Wistar rats. Isolated Langendorff-mode-perfused rat hearts were subjected to the following events: basal condition, electrically induced VF lasting 2 min, electrically induced VF lasting 10 min, and sustained VF followed by spontaneous sinus rhythm restoration due to transient stop perfusion. The hearts were snap frozen at each event; ventricular tissue was sent for Cx43 immunoblotting using rabbit antiCx43 polyclonal antibody to detect phosphorylated (P-Cx43) as well as unphosphorylated (noP-Cx43) forms of Cx43, and mouse antiCx43 monoclonal antibody to detect noP-Cx43 only. Compared with basal conditions, total Cx43 expression did not change during experiments in either male or female rat hearts. However, P-Cx43 and the ratio of P-Cx43 to total Cx43 decreased significantly due to VF lasting 2 min and 10 min in male rat hearts only. In parallel, there was a significant increase in noP-Cx43 due to VF lasting 2 min and 10 min in male rat hearts only. Surprisingly, an enhancement of noP-Cx43 linked with suppression of P-Cx43 was detected during stop perfusion-induced termination of VF lasting 2 min, followed by sinus rhythm restoration in both male and female rat hearts. Sinus rhythm was not restored after 10 min of

  6. Abnormal myocardial perfusion and risk of heart failure in patients with type 2 diabetes mellitus

    PubMed Central

    Utrera-Lagunas, Marcelo; Orea-Tejeda, Arturo; Castillo-Martínez, Lilia; Balderas-Muñoz, Karla; Keirns-Davis, Candace; Espinoza-Rosas, Sarahi; Sánchez-Ortíz, Néstor Alonso; Olvera-Mayorga, Gabriela

    2013-01-01

    BACKGROUND: Diabetes is a major risk factor for heart failure (HF), although the pathophysiological processes have not been clarified. OBJECTIVE: To determine the prevalence of HF and of abnormal myocardial perfusion in diabetic patients evaluated using technetium (99m) sestamibi single-photon emission computed tomography. METHODS: An observational cross-sectional study was conducted that included patients with type 2 diabetes mellitus who underwent echocardiography to diagnose HF and a pharmacological stress test with intravenous dipyridamole to examine cardiac scintigraphic perfusion abnormalities. Clinical and biochemical data were also collected. RESULTS: Of the 160 diabetic patients included, 92 (57.6%) were in HF and 68 (42.5%) were not. When patients were stratified according to the presence of abnormal myocardial perfusion, those with abnormal perfusion had a higher prevalence of HF (93%) than those with normal perfusion (44.4%) (P<0.0001). Patients with HF weighed more (P=0.03), used insulin less frequently (P=0.01), had lower total cholesterol (P=0.05) and high-density lipoprotein cholesterol concentrations (P=0.002), and a greater number of their myocardial segments showed abnormal perfusion (P≤0.001). More HF patients had a history of myocardial infarction (P<0.001) compared with those without HF. In a logistic regression analysis, the number of segments exhibiting abnormal myocardial perfusion was an independent risk factor for HF. CONCLUSIONS: The prevalence of HF in diabetic patients was high and HF predominantly occured in association with myocardial ischemia. PMID:24294048

  7. Illustrated Imaging Essay on Congenital Heart Diseases: Multimodality Approach Part II: Acyanotic Congenital Heart Disease and Extracardiac Abnormalities.

    PubMed

    Bhat, Venkatraman; Belaval, Vinay; Gadabanahalli, Karthik; Raj, Vimal; Shah, Sejal

    2016-06-01

    Acyanotic heart disease constitutes a significant majority of patient who may present with non-cardiac symptoms. Either they are detected incidentally or present with respiratory complaints. Equipped with knowledge of anatomy by echocardiography and radiographic methods described in previous part of this presentation, diagnosis may be confidently attempted. On plain radiography acyanotic congenital heart diseases have variable appearance depending upon severity of disease. Cardiac size, chamber enlargement and pulmonary vascular pattern are key elements. Typically left to right shunts with large volume flow are associated with pulmonary plethora. Plain radiography has an important role in detecting manifestation of pulmonary arterial hypertension. Severe stenosis of pulmonary valve is associated with pulmonary oligemia. Small intra-cardiac shunts and anomalies of coronary arteries generally present with normal cardiac size and pulmonary arterial pattern. Disease spectrum presented in this illustration demands thorough scrutiny of pulmonary, osseous and abdominal abnormalities. This section illustrates some commonly encountered spectrum of acyanotic cardiac disease. PMID:27504381

  8. Illustrated Imaging Essay on Congenital Heart Diseases: Multimodality Approach Part II: Acyanotic Congenital Heart Disease and Extracardiac Abnormalities

    PubMed Central

    Belaval, Vinay; Gadabanahalli, Karthik; Raj, Vimal; Shah, Sejal

    2016-01-01

    Acyanotic heart disease constitutes a significant majority of patient who may present with non-cardiac symptoms. Either they are detected incidentally or present with respiratory complaints. Equipped with knowledge of anatomy by echocardiography and radiographic methods described in previous part of this presentation, diagnosis may be confidently attempted. On plain radiography acyanotic congenital heart diseases have variable appearance depending upon severity of disease. Cardiac size, chamber enlargement and pulmonary vascular pattern are key elements. Typically left to right shunts with large volume flow are associated with pulmonary plethora. Plain radiography has an important role in detecting manifestation of pulmonary arterial hypertension. Severe stenosis of pulmonary valve is associated with pulmonary oligemia. Small intra-cardiac shunts and anomalies of coronary arteries generally present with normal cardiac size and pulmonary arterial pattern. Disease spectrum presented in this illustration demands thorough scrutiny of pulmonary, osseous and abdominal abnormalities. This section illustrates some commonly encountered spectrum of acyanotic cardiac disease. PMID:27504381

  9. Abnormal Heart Rate Turbulence Predicts Cardiac Mortality in Low, Intermediate and High Risk Older Adults

    PubMed Central

    Stein, Phyllis K.; Barzilay, Joshua I.

    2011-01-01

    Introduction We examined whether heart rate turbulence (HRT) adds to traditional risk factors for cardiac mortality in older adults at low, intermediate and high risk. Methods and Results N=1298, age ≥65 years, with 24-hour Holter recordings were studied. HRT, which quantifies heart rate response to ventricular premature contractions, was categorized as: both turbulence onset (TO) and turbulence slope (TS) normal; TO abnormal; TS abnormal; or both abnormal. Independent risks for cardiac mortality associated with HRT or, for comparison, elevated C-reactive protein (CRP) (>3.0 mg/L), were calculated using Cox regression analysis adjusted for traditional cardiovascular disease risk factors and stratified by the presence of no, isolated subclinical (i.e., intermediate risk) or clinical CVD. Having both TS and TO abnormal compared to both normal was associated with cardiac mortality in the low risk group [HR 7.9, 95% CI 2.8–22.5, (p<0.001)]. In the high and intermediate risk groups, abnormal TS and TO ([HR 2.2, 95% CI 1.5–4.0, p=0.016] and [HR 2.7, 95% CI 1.2–5.9, p=0.012]), respectively, were also significantly associated with cardiac mortality. In contrast, elevated CRP was associated with increased cardiac mortality risk only in low risk individuals [HR 2.5, 95% CI 1.3–5.1, p=0.009]. In the low risk group, the c-statistic was 0.706 for the base model, 0.725 for the base model with CRP, and 0.767 for the base model with HRT. Conclusions Abnormal HRT independently adds to risk stratification of low, intermediate and high risk individuals but appears to add especially to the stratification of those considered at low risk. PMID:21134026

  10. [The dependence of the heart rhythm on anxiousness as a stable individual characteristic].

    PubMed

    Danilova, N N; Korshunova, S G; Sokolov, E N; Chernyshenko, E N

    1995-01-01

    In 90 subjects (25 males and 65 females) aged 17-19 heart and respiration rates were telemetrically recorded with a "Sport" polygraph under conditions of rest and arithmetical load (periods of 3 min each). Spectral analysis of heart rate and respiration and statistical processing was performed off-line by an IBM PC XT with the software package PFE2. Anxiety was tested according to Spielberger State-Trait-Anxiety Inventory with Hanin modification and strength of excitation and inhibition according to Strelau Temperament Inventory. It was shown that the group characterized by the high trait-anxiety had significantly higher resting heart rate and Baevskiĭ index of strain than the group with low trait-anxiety. The groups differed also in R-R interval variability (standard deviation) under arithmetic load. In the group with high trait-anxiety R-R interval variability was lower than in the other group mainly in two frequency bands of R-R power spectrum, i. e., those of respiratory arrhythmia (RA) and Traube-Hering-Mayer waves (THM). Mental load evoked an increase in the heart rate and Baevskiĭ index and decrease in the power of RA and THM frequency bands. Such peculiarities of the heart rate in both groups during the periods of rest and informational load can be explained in the framework of reciprocal relationship between orienting (lower trait-anxiety, lower heart rate, higher R-R interval variability mainly in RA and THM bands of R-R power spectrum) and defensive reflexes (higher trait-anxiety, higher heart rate, lower R-R interval variability, in particular in RA and THM bands of R-R power spectrum. PMID:8540248

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

    PubMed

    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. PMID:27379594

  12. Pulmonary Congestion at Rest and Abnormal Ventilation During Exercise in Chronic Systolic Heart Failure

    PubMed Central

    Malfatto, Gabriella; Caravita, Sergio; Giglio, Alessia; Rossi, Jessica; Perego, Giovanni B; Facchini, Mario; Parati, Gianfranco

    2015-01-01

    Background In patients with chronic heart failure, abnormal ventilation at cardiopulmonary testing (expressed by minute ventilation-to-carbon dioxide production, or VE/VCO2 slope, and resting end-tidal CO2 pressure) may derive either from abnormal autonomic or chemoreflex regulation or from lung dysfunction induced by pulmonary congestion. The latter hypothesis is supported by measurement of pulmonary capillary wedge pressure, which cannot be obtained routinely but may be estimated noninvasively by measuring transthoracic conductance (thoracic fluid content 1/kΩ) with impedance cardiography. Methods and Results Preliminarily, in 9 patients undergoing invasive hemodynamics during cardiopulmonary testing, we demonstrated a significant relationship between VE/VCO2 slope and resting end-tidal CO2 pressure with baseline and peak pulmonary capillary wedge pressure. Later, noninvasive hemodynamic evaluation by impedance cardiography was performed before cardiopulmonary testing in 190 patients with chronic systolic heart failure and normal lung function (aged 67±3 years, 71% with ischemia, ejection fraction 32±7%, 69% with implantable cardioverter-defibrillator or cardiac resynchronization therapy). In this group, we determined the relationship between abnormal ventilation (VE/VCO2 slope and resting end-tidal CO2 pressure) and transthoracic conductance. In the whole population, thoracic fluid content values were significantly related to VE/VCO2 slope (R=0.63, P<0.0001) and to resting end-tidal CO2 pressure (R=−0.44, P<0.001). Conclusions In patients with chronic heart failure, abnormal ventilation during exercise may be related in part to pulmonary congestion, as detected by resting baseline impedance cardiography. PMID:25944875

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

    PubMed

    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. PMID:24767959

  14. Management of atrial fibrillation in patients with chronic kidney disease in Europe Results of the European Heart Rhythm Association Survey.

    PubMed

    Potpara, Tatjana S; Lenarczyk, Radoslaw; Larsen, Torben B; Deharo, Jean-Claude; Chen, Jian; Dagres, Nikolaos

    2015-12-01

    The purpose of this European Heart Rhythm (EHRA) Scientific Initiatives Committee EP Wire Survey was to assess 'real-world' practice in the management of patients with atrial fibrillation (AF) and chronic kidney disease (CKD) in the European Eelectrophysiology centres. Of 41 responding centres, 39 (95.1%) and 37 (90.2%) routinely evaluated renal function in AF patients at first presentation and during follow-up, respectively, but 13 centres (31.7%) re-assessed advanced CKD only at ≥1-year intervals. While the use of oral anticoagulants (OACs) in mild-to-moderate CKD patients was mostly guided by individual patient stroke risk, 31% of the centres used no therapy, or aspirin or the left appendage occlusion in patients with advanced CKD and HAS-BLED ≥ 3. Vitamin K antagonists (VKAs) were preferred in patients with severe CKD or under renal replacement therapy (RRT), any non-VKA in patients with mild CKD, and apixaban in patients with moderate CKD. Rhythm control was preferred in patients with mild-to-moderate CKD (48.7% of centres), and rate control in patients with severe CKD (51.2% of centres). In 20 centres (48.8%), AF ablation was not performed in advanced CKD patients. Most centres performed AF ablation on OAC, but heparin bridging was still used in >10% of centres. Our survey has shown that the importance of renal function monitoring in AF patients is well recognized in clinical practice. In patients with mild-to-moderate CKD, AF is mostly managed according to the guideline recommendations, but more data are needed to guide the management of AF in patients with severe CKD or RRT. PMID:26733617

  15. Aging and CaMKII alter intracellular Ca2+ transients and heart rhythm in Drosophila melanogaster.

    PubMed

    Santalla, Manuela; Valverde, Carlos A; Harnichar, Ezequiel; Lacunza, Ezequiel; Aguilar-Fuentes, Javier; Mattiazzi, Alicia; Ferrero, Paola

    2014-01-01

    Aging is associated to disrupted contractility and rhythmicity, among other cardiovascular alterations. Drosophila melanogaster shows a pattern of aging similar to human beings and recapitulates the arrhythmogenic conditions found in the human heart. Moreover, the kinase CaMKII has been characterized as an important regulator of heart function and an arrhythmogenic molecule that participate in Ca2+ handling. Using a genetically engineered expressed Ca2+ indicator, we report changes in cardiac Ca2+ handling at two different ages. Aging prolonged relaxation, reduced spontaneous heart rate (HR) and increased the occurrence of arrhythmias, ectopic beats and asystoles. Alignment between Drosophila melanogaster and human CaMKII showed a high degree of conservation and indicates that relevant phosphorylation sites in humans are also present in the fruit fly. Inhibition of CaMKII by KN-93 (CaMKII-specific inhibitor), reduced HR without significant changes in other parameters. By contrast, overexpression of CaMKII increased HR and reduced arrhythmias. Moreover, it increased fluorescence amplitude, maximal rate of rise of fluorescence and reduced time to peak fluorescence. These results suggest that CaMKII in Drosophila melanogaster acts directly on heart function and that increasing CaMKII expression levels could be beneficial to improve contractility. PMID:25003749

  16. Aging and CaMKII Alter Intracellular Ca2+ Transients and Heart Rhythm in Drosophila melanogaster

    PubMed Central

    Santalla, Manuela; Valverde, Carlos A.; Harnichar, Ezequiel; Lacunza, Ezequiel; Aguilar-Fuentes, Javier; Mattiazzi, Alicia; Ferrero, Paola

    2014-01-01

    Aging is associated to disrupted contractility and rhythmicity, among other cardiovascular alterations. Drosophila melanogaster shows a pattern of aging similar to human beings and recapitulates the arrhythmogenic conditions found in the human heart. Moreover, the kinase CaMKII has been characterized as an important regulator of heart function and an arrhythmogenic molecule that participate in Ca2+ handling. Using a genetically engineered expressed Ca2+ indicator, we report changes in cardiac Ca2+ handling at two different ages. Aging prolonged relaxation, reduced spontaneous heart rate (HR) and increased the occurrence of arrhythmias, ectopic beats and asystoles. Alignment between Drosophila melanogaster and human CaMKII showed a high degree of conservation and indicates that relevant phosphorylation sites in humans are also present in the fruit fly. Inhibition of CaMKII by KN-93 (CaMKII-specific inhibitor), reduced HR without significant changes in other parameters. By contrast, overexpression of CaMKII increased HR and reduced arrhythmias. Moreover, it increased fluorescence amplitude, maximal rate of rise of fluorescence and reduced time to peak fluorescence. These results suggest that CaMKII in Drosophila melanogaster acts directly on heart function and that increasing CaMKII expression levels could be beneficial to improve contractility. PMID:25003749

  17. Bone and heart abnormalities of subclinical hyperthyroidism in women below the age of 65 years.

    PubMed

    Rosario, Pedro Weslley

    2008-12-01

    The objective of the present study was to evaluate bone and cardiac abnormalities and symptoms and signs of thyroid hormone excess in women with subclinical hyperthyroidism (SCH) aged < 65 years. Forty-eight women with SCH were evaluated. The control group consisted of 48 euthyroid volunteers. The mean symptom rating scale score was significantly higher in patients. Cardiac involvement, both morphological and affecting systolic and diastolic functions, was also observed in patients. Women with SCH showed a significant increase in serum markers of bone formation and resorption. In addition, bone mineral density (BMD) was lower in the femoral neck but not in the lumbar spine in patients before menopause, whereas a lower BMD was observed at both sites in postmenopausal patients. SCH is not completely asymptomatic in women aged < 65 years, and is associated with heart abnormalities and with increased bone turnover and reduced BMD even before menopause. PMID:19197452

  18. Analysis of electrolyte abnormalities and the mechanisms leading to arrhythmias in heart failure. A literature review.

    PubMed

    Urso, C; Canino, B; Brucculeri, S; Firenze, A; Caimi, G

    2016-01-01

    About 50% of deaths from heart failure (HF) are sudden, presumably referable to arrhythmias. Electrolyte and acid-base abnormalities are a frequent and potentially dangerous complication in HF patients. Their incidence is almost always correlated with the severity of cardiac dysfunction; furthermore leading to arrhythmias, these imbalances are associated with a poor prognosis. The frequency of ventricular ectopic beats and sudden cardiac death correlate with both plasma and whole body levels of potassium, especially in alkalemia. The early recognition of these alterations and the knowledge of the pathophysiological mechanisms are useful for the management of these HF patients. PMID:27598028

  19. Noninvasive recovery of epicardial potentials in a realistic heart-torso geometry. Normal sinus rhythm.

    PubMed

    Messinger-Rapport, B J; Rudy, Y

    1990-04-01

    The inverse problem in electrocardiography implies the reconstruction of electrical events within the heart from information measured noninvasively on the body surface. Deduction of these electrical events is possible from measured epicardial potentials, and, thus, a noninvasive method of recovering epicardial potentials from body surface data is useful in experimental and clinical studies. In the present study, an inverse method that uses Tikhonov regularization was shown to reconstruct, with good accuracy, important events in cardiac excitation. The inverse procedure was employed on data obtained from a human-torso tank in which a beating canine heart was placed in the correct anatomical position. Comparison with the actual, measured epicardial potentials indicates that positions and shapes of potential features (maxima, minima, zero potential line, saddles, etc.) are recovered with good accuracy throughout the QRS. An error in position of up to 1 cm is typical, while amplitudes are slightly diminished. In addition, application was extended from the above setting, in which the geometry was precisely known and potentials at a large number of leads were measured accurately, to a situation that is more representative of clinical and experimental settings. Effects of inaccuracy in location of the position of the heart were examined. A stylized torso that approximates the actual geometry was designed, and its performance in the inverse computations was evaluated. A systematic method of reduction of the number of leads on the body surface was proposed, and the resulting lead configurations were evaluated in terms of the accuracy of inverse solutions. The results indicate that the inverse problem can be stabilized with respect to different types of uncertainties in measured data and offer promise in the use of the inverse procedure in clinical and experimental situations. PMID:2317885

  20. The use of wearable cardioverter-defibrillators in Europe: results of the European Heart Rhythm Association survey.

    PubMed

    Lenarczyk, Radosław; Potpara, Tatjana S; Haugaa, Kristina H; Hernández-Madrid, Antonio; Sciaraffia, Elena; Dagres, Nikolaos

    2016-01-01

    The aim of this European Heart Rhythm Association (EHRA) survey was to collect data on the use of wearable cardioverter-defibrillators (WCDs) among members of the EHRA electrophysiology research network. Of the 50 responding centres, 23 (47%) reported WCD use. Devices were fully reimbursed in 17 (43.6%) of 39 respondents, and partially reimbursed in 3 centres (7.7%). Eleven out of 20 centres (55%) reported acceptable patients' compliance (WCD worn for >90% of time). The most common indications for WCD (8 out of 10 centres; 80%) were covering the period until re-implantation of ICD explanted due to infection, in patients with left ventricular impairment due to myocarditis or recent myocardial infarction and those awaiting heart transplantation. Patient life expectancy of <12 months and poor compliance were the most commonly reported contraindications for WCD (24 of 46 centres, 52.2%). The major problems encountered by physicians managing patients with WCD were costs (8 of 18 centres, 44.4%), non-compliance, and incorrect use of WCD. Four of 17 centres (23.5%) reported inappropriate WCD activations in <5% of patients. The first shock success rate in terminating ventricular arrhythmias was 95-100% in 6 of 15 centres (40%), 85-95% in 4 (26.7%), 75-85% in 2 (13.3%), and <75% in 3 centres (20%). The survey has shown that the use of WCD in Europe is still restricted and depends on reimbursement. Patients' compliance remains low. Heterogeneity of indications for WCD among centres underscores the need for further research and a better definition of indications for WCD in specific patient groups. PMID:26842735

  1. How are arrhythmias managed in the paediatric population in Europe? Results of the European Heart Rhythm survey.

    PubMed

    Hernández-Madrid, Antonio; Hocini, Mélèze; Chen, Jian; Potpara, Tatjana; Pison, Laurent; Blomström-Lundqvist, Carina

    2014-12-01

    The aim of this survey was to provide insight into current practice regarding the management of paediatric arrhythmias in Europe. The survey was based on a questionnaire sent via the Internet to the European Heart Rhythm Association (EHRA) electrophysiology research network centres. The following topics were explored: patient and treatment selection, techniques and equipment, treatment outcomes and complications. The vast majority of paediatric arrhythmias concerns children older than 1 year and patients with grown-up congenital heart disease. In 65% of the hospitals there is a specialized paediatric centre, and the most commonly observed arrhythmias include Wolff-Parkinson-White syndrome and atrioventricular nodal re-entry tachycardias (90.24%). The medical staff performing paediatric catheter ablations in Europe are mainly adult electrophysiology teams (82.05% of the centres). Radiofrequency is the preferred energy source used for paediatric arrhythmia ablation. Catheter ablation is only chosen if two or more antiarrhythmic drugs have failed (94.59% of the centres). The majority of the centres use flecainide (37.8%) or atenolol (32.4%) as their first choice drug for prevention of recurrent supraventricular arrhythmias. While none of the centres performed catheter ablation in asymptomatic infants with pre-excitation, 29.7% recommend ablation in asymptomatic children and adolescents. The preferred choice for pacemaker leads in infants less than 1 year old is implantation of epicardial leads in 97.3% of the centres, which continues to be the routine even in patients between 1 and 5 years of age as reported by 75.68% of the hospitals. Almost all centres (94.59%) report equally small number of complications of catheter ablation in children (aged 1-14 years) as observed in adults. PMID:25417228

  2. Cardiac Rhythm Monitoring After Acute Decompensation for Heart Failure: Results from the CARRYING ON for HF Pilot Study

    PubMed Central

    Mortara, Andrea; Diotallevi, Paolo; Gallone, Giuseppe; Mariconti, Barbara; Gronda, Edoardo; Gentili, Alessandra; Bisetti, Silvia; Botto, Giovanni Luca

    2016-01-01

    Background There’s scarce evidence about cardiovascular events (CV) in patients with hospitalization for acute heart failure (HF) and no indication for immediate device implant. Objective The CARdiac RhYthm monitorING after acute decompensatiON for Heart Failure study was designed to assess the incidence of prespecified clinical and arrhythmic events in this patient population. Methods In this pilot study, 18 patients (12 (67%) male; age 72±10; 16 (89%) NYHA II-III), who were hospitalized for HF with low left ventricular ejection fraction (LVEF) (<40%) and no immediate indication for device implant received an implantable loop recorder (ILR) before hospital discharge. Follow-up visits were scheduled at 3 and 6 months, and at every 6 months until study closure; device data were remotely reviewed monthly. CV mortality, unplanned CV hospitalization, and major arrhythmic events during follow-up were analyzed. Results During a median follow-up of 593 days, major CV occurred in 13 patients (72%); of those, 7 patients had at least 1 cardiac arrhythmic event, 2 had at least a clinical event (CV hospitalization or CV death), and 4 had both an arrhythmic and a CV event. Six (33%) patients experienced 10 major clinical events, 5 of them (50%) were HF related. During follow-up, 2 (11%) patients died due to a CV cause and 3 (16%) patients received a permanent cardiac device. Conclusions After an acute HF hospitalization, patients with LVEF<40% and who are not readily eligible for permanent cardiac device implant have a known high incidence of major CV event. In these patients, ILR allows early detection of major cardiac arrhythmias and the ability to react appropriately in a timely manner. Trial Registration ClinicalTrials.gov NCT01216670; https://clinicaltrials.gov/ct2/show/NCT01216670 PMID:27118481

  3. Left atrial appendage closure-indications, techniques, and outcomes: results of the European Heart Rhythm Association Survey.

    PubMed

    Pison, Laurent; Potpara, Tatjana S; Chen, Jian; Larsen, Torben B; Bongiorni, Maria Grazia; Blomström-Lundqvist, Carina

    2015-04-01

    The purpose of this EP Wire was to assess the indications, techniques, and outcomes of left atrial appendage occlusion (LAAO) in Europe. Thirty-three European centres, all members of the European Heart Rhythm Association electrophysiology (EP) research network, responded to this survey by completing the questionnaire. The major indication for LAAO (94%) was the prevention of stroke in patients at high thrombo-embolic risk (CHA2DS2-VASc ≥ 2) and contraindications to oral anticoagulants (OACs). Twenty-one (64%) of the responding centres perform LAAO in their own institution and 80% implanted 30 or less LAAO devices in 2014. Two-dimensional transoesophageal echocardiography was the preferred imaging technique to visualize LAA before, during, and after LAAO in 79, 58, and 62% of the participating centres, respectively. Following LAAO, 49% of the centres prescribe vitamin K antagonists or novel OACs. Twenty-five per cent of the centres combine LAAO with pulmonary vein isolation. The periprocedural complications included death (range, 0-3%), ischaemic or haemorrhagic stroke (0-25%), tamponade (0-25%), and device embolization (0-20%). In conclusion, this EP Wire has demonstrated that LAAO is most commonly employed in patients at high thrombo-embolic risk in whom OAC is contraindicated. The technique is not yet very widespread and the complication rates remain significant. PMID:25833883

  4. Preferred tools and techniques for implantation of cardiac electronic devices in Europe: results of the European Heart Rhythm Association survey.

    PubMed

    Bongiorni, Maria Grazia; Proclemer, Alessandro; Dobreanu, Dan; Marinskis, Germanas; Pison, Laurent; Blomstrom-Lundqvist, Carina

    2013-11-01

    The aim of this European Heart Rhythm Association (EHRA) survey was to assess clinical practice in relation to the tools and techniques used for cardiac implantable electronic devices procedures in the European countries. Responses to the questionnaire were received from 62 members of the EHRA research network. The survey involved high-, medium-, and low-volume implanting centres, performing, respectively, more than 200, 100-199 and under 100 implants per year. The following topics were explored: the side approach for implantation, surgical techniques for pocket incision, first venous access for lead implantation, preference of lead fixation, preferred coil number for implantable cardioverter-defibrillator (ICD) leads, right ventricular pacing site, generator placement site, subcutaneous ICD implantation, specific tools and techniques for cardiac resynchronization therapy (CRT), lead implantation sequence in CRT, coronary sinus cannulation technique, target site for left ventricular lead placement, strategy in left ventricular lead implant failure, mean CRT implantation time, optimization of the atrioventricular (AV) and ventriculo-ventricular intervals, CRT implants in patients with permanent atrial fibrillation, AV node ablation in patients with permanent AF. This panoramic view allows us to find out the operator preferences regarding the techniques and tools for device implantation in Europe. The results showed different practices in all the fields we investigated, nevertheless the survey also outlines a good adherence to the common standards and recommendations. PMID:24170423

  5. Management of malfunctioning and recalled pacemaker and defibrillator leads: results of the European Heart Rhythm Association survey.

    PubMed

    Grazia Bongiorni, Maria; Dagres, Nikolaos; Estner, Heidi; Pison, Laurent; Todd, Derick; Blomstrom-Lundqvist, Carina

    2014-11-01

    The aim of this survey was to describe the different strategies regarding the management of malfunctioning and recalled pacemaker and defibrillator leads across Europe. A questionnaire has been designed to assess the current practice and physician's approach to the management of leads which are faulty, unnecessary, and/or recalled. Responses to the questionnaire were received from 34 hospitals-members of the European Heart Rhythm Association (EHRA) electrophysiology (EP) research network. The survey involved both very high and low volume implanting centres, with 85% of the responding centres performing lead extraction. The survey provides a panoramic view of operator's decision making in the field of malfunctioning, recalled, and redundant leads and outlines a common point of view on lead abandonment and factors influencing the decision about lead extraction. The main factors strongly influencing the decision making were patient's age (59%), the presence of the damaged leads (44%), and the lead dwelling time (44%). Regarding the lead abandonment, the main concern (61%) was the potential greater difficulty associated with lead extraction in the future. High volume extracting centres showed a greater propensity to removing the malfunctioning or recalled leads compared with low volume or non-extracting centres. This EP Wire survey gives a snapshot of the operators' approaches and options regarding redundant, malfunctioning, and recalled lead management and may form the basis for future prospective research on this topic. PMID:25344962

  6. Cardioversion for atrial fibrillation in current European practice: results of the European Heart Rhythm Association survey.

    PubMed

    Hernández-Madrid, Antonio; Svendsen, Jesper Hastrup; Lip, Gregory Y H; Van Gelder, Isabelle C; Dobreanu, Dan; Blomstrom-Lundqvist, Carina

    2013-06-01

    This survey was conducted to provide an insight into the current clinical practice regarding the use of cardioversion for atrial fibrillation (AF) in Europe. Responses were received from 57 centres across Europe, 71.9% of which were university hospitals. For electrical cardioversion, general anaesthesia was managed by an anaesthesiologist in 73.9% of centres and by a cardiologist in 37%. In the majority of centres, electrical cardioversion was performed using a biphasic defibrillator (85.1%). Antiarrhythmic drugs were routinely prescribed prior to electrical cardioversion by 54.3% of hospitals. For pharmacological cardioversion in patients with no or minimal heart disease, the majority of centres (63.1%) chose intravenous flecainide or propafenone, whereas vernakalant was used by 35% of centres in patients with no or minimal-to-moderate structural heart disease. Most centres (71.7%) used a mandatory strategy of 3 weeks of oral anticoagulation prior to elective cardioversion in patients AF > 48 h, but 28.3% performed immediate cardioversion after a transoesophageal echocardiogram. Many centres are now performing electrical cardioversion on treatment with novel oral anticoagulants (up to 23.6% of cardioversions). PMID:23709570

  7. [HEART RHYTHM VARIABILITY ANALYSIS AND ASSESSMENT OF THE SPINAL PAIN SYNDROME DURING DRY IMMERSION].

    PubMed

    Sun, I; Voronkov, Yu I; Ardashev, V N; Glukhova, S I

    2015-01-01

    The spinal pain syndrome appears in cosmonauts on both short and long-duration missions. This untoward factor may affect body systems functioning and complicate the successful accomplishment of space mission. Purpose of the investigation was to examine the lumbar spine and to elucidate whether its condition relates to the spinal pain development and changes in heart rate variability (HRV) in the microgravity environment. The experiment was conducted in dry immersion as a method of microgravity effects simulation. It was shown that in dry immersion locomotion reproduces the patterns peculiar for significant gravitational unloading. Spinal pain intensity, angles and heights of the lumbar intervertebral discs and HRV were measured in 19 selected volunteers. During the experiment, all the volunteers developed pains in the back that abated gradually. Pain dependence on the height of intervertebral discs and cardiac regulatory mechanisms were investigated. PMID:26292423

  8. Abnormal time course of low beta modulation in non-fluent preschool children: A magnetoencephalographic study of rhythm tracking.

    PubMed

    Etchell, Andrew C; Ryan, Margaret; Martin, Erin; Johnson, Blake W; Sowman, Paul F

    2016-01-15

    Stuttering is a disorder of speech affecting millions of people around the world. Whilst the exact aetiology of stuttering remains unknown, it has been hypothesised that it is a disorder of the neural mechanisms that support speech timing. In this article, we used magnetoencephalography (MEG) to examine activity from auditory regions of the brain in stuttering and non-stuttering children aged 3-9years. For typically developing children, we found that MEG oscillations in the beta band responded to rhythmic sounds with a peak near the time of stimulus onset. In contrast, stuttering children showed an opposite phase of beta band envelope, with a trough of activity at stimulus onset. These results suggest that stuttering may result from abnormalities in predictive brain responses which are reflected in abnormal entrainment of the beta band envelope to rhythmic sounds. PMID:26545455

  9. Protective Effects of Ginger (Zingiber officinale) Extract against Diabetes-Induced Heart Abnormality in Rats

    PubMed Central

    Ilkhanizadeh, Behrouz; Khadem Ansari, Mohamad hasan; Nemati, Samira; Rasmi, Yusef

    2016-01-01

    Background Diabetic cardiomyopathy is an important causal factor in morbidity and mortality among diabetic patients, and currently, no effective means are available to reverse its pathological progress. The purpose of the present study was to investigate the effect of ginger extract on apolipoproteins (apo) A and B, hyperhomocysteinemia, cathepsin G and leptin changes, as well as cardiac fibrosis and heart muscle cell proliferation under hyperglycemic conditions in vivo. Methods Twenty-four male Wistar rats were divided into three groups, namely: control, non-treated diabetic, and ginger extract-treated diabetic groups. The ginger extract-treated diabetic group received a 50 mg daily dose of ginger extract intragastrically for 6 weeks. Results The results revealed concurrent significant increases in plasma C-reactive protein (CRP), homocysteine (Hcy), cathepsin G and apoB levels and decreases in apoA and leptin levels in the non-treated diabetic group compared to the control group. Moreover, heart structural changes, including fibrosis and heart muscle cell proliferation, were observed in non-treated diabetic rats compared to the control rats. Significant amelioration of changes in the heart structure together with restoration of the elevated levels of Hcy and CRP, leptin, cathepsin G, and apoA and B were found in the ginger extract-treated diabetic group compared to the non-treated diabetic group. Conclusion The findings indicated that ginger extract significantly reduces heart structural abnormalities in diabetic rats and that these effects might be associated with improvements in serum apo, leptin, cathepsin G, and Hcy levels and with the antioxidant properties of ginger extract. PMID:26912155

  10. Clinical significance of exercise-induced left ventricular wall motion abnormality occurring at a low heart rate

    SciTech Connect

    Kimchi, A.; Rozanski, A.; Fletcher, C.; Maddahi, J.; Swan, H.J.; Berman, D.S.

    1987-10-01

    We studied the relationship between the heart rate at the time of onset of exercise-induced wall motion abnormality and the severity of coronary artery disease in 89 patients who underwent exercise equilibrium radionuclide ventriculography as part of their evaluation for coronary artery disease. Segmental wall motion was scored with a five-point system (3 = normal; -1 = dyskinesis); a decrease of one score defined the onset of wall motion abnormality. The onset of wall motion abnormality at less than or equal to 70% of maximal predicted heart rate had 100% predictive accuracy for coronary artery disease and higher sensitivity than the onset of ischemic ST segment depression at similar heart rate during exercise: 36% (25 of 69 patients with coronary disease) vs 19% (13 of 69 patients), p = 0.01. Wall motion abnormality occurring at less than or equal to 70% of maximal predicted heart rate was present in 49% of patients (23 of 47) with critical stenosis (greater than or equal to 90% luminal diameter narrowing), and in only 5% of patients (2 of 42) without such severe stenosis, p less than 0.001. The sensitivity of exercise-induced wall motion abnormality occurring at a low heart rate for the presence of severe coronary artery disease was similar to that of a deterioration in wall motion by more than two scores during exercise (49% vs 53%) or an absolute decrease of greater than or equal to 5% in exercise left ventricular ejection fraction (49% vs 45%).

  11. Development of regulation of the cardiac chronotropic function in albino rats during the early postnatal ontogeny according to the results of spectral analysis of heart rhythm variability.

    PubMed

    Kurjanova, E V; Teplyj, D L; Zereninova, N V

    2012-04-01

    Regulation of the cardiac chronotropic function was studied by spectral analysis of cardiac rhythm variability in HF, LF, and VLF bands in rats at various stages of the early postnatal ontogeny. The inadequacy of the regulatory mechanisms during the first days of life manifested by low power of all waves (particularly HF) in the cardiac rhythm variability spectrum. On day 14 of life, the cardiointerval variability was formed by HF waves, their low power together with increasing heart rate indicating more intense sympathetic effects. On day 21 of life, a potent elevation of the VLF power reflected a stronger centralization of regulation from higher autonomic centers. The age of 28 days was characterized by a sharp increase of HF activity and could be regarded as the turning point in the development of parasympathetic effects and activity of the autonomic regulation contour. From the age of 35 days, the wave power and the proportion of the spectral components of cardiac rhythm variability in albino rats corresponded to the adult pattern; a trend to the central regulation predominance and to greater rigidity of cardiac rhythm formed only with the onset of sexual maturation. PMID:22803162

  12. Replacement of implantable cardioverter defibrillators and cardiac resynchronization therapy devices: results of the European Heart Rhythm Association survey.

    PubMed

    Tilz, Roland; Boveda, Serge; Deharo, Jean-Claude; Dobreanu, Dan; Haugaa, Kristina H; Dagres, Nikolaos

    2016-06-01

    The aim of this EP Wire was to assess the management, indications, and techniques for implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT) device replacement in Europe. A total of 24 centres in 14 European countries completed the questionnaire. All centres were members of the European Heart Rhythm Association Electrophysiology Research Network. Replacement procedures were performed by electrophysiologists in 52% of the centres, by cardiologists in 33%, and both in the remaining centres. In the majority of centres, the procedures were performed during a short hospitalization (<2 days; 61.2%), or on an outpatient basis (28%). The overwhelming majority of centres reported that they replaced ICDs at the end of battery life. Only in a small subset (<10%) of patients with ICD for primary prevention and without ventricular tachycardia (VT) since implantation, ICD was not replaced. In inherited primary arrhythmia syndromes, 80% of the centres always replaced the ICD at the end of battery life. After VT ablation, only few centres (9%) explanted or downgraded the device that was previously implanted for secondary prevention, but only in those patients without new VT episodes. Patient's life expectancy <1 year was the most commonly reported reason (61%) to downgrade from a CRT-D to a CRT-P device. While warfarin therapy was continued in 47% of the centres, non-vitamin K oral anticoagulants were discontinued without bridging 24 h prior to replacement procedures in 60%. Finally, in 65% of the centres, VT induction and shock testing during ICD and CRT-D replacement were performed only in the case of leads with a warning or with borderline measurements. This survey provides a snapshot of the perioperative management, indications, and techniques of ICD and CRT device replacement in Europe. It demonstrates some variations between participating centres, probably related to local policies and to the heterogeneity of the ICD population. PMID

  13. Circadian Rhythms

    MedlinePlus

    ... chronobiology. Are circadian rhythms the same thing as biological clocks? No, but they are related. Our biological clocks drive our circadian rhythms. What are biological clocks? The biological clocks that control circadian rhythms ...

  14. Non-vitamin K oral anticoagulants in patients with atrial fibrillation after cardiac surgery: the results of the European Heart Rhythm Association Survey.

    PubMed

    Vranckx, Pascal; Potpara, Tatjana; Dagres, Nikolaos; Heidbuchel, Hein

    2016-07-01

    The purpose of this European Heart Rhythm Association survey was to assess the current practice concerning the use of oral anticoagulation in patients with post-operative atrial fibrillation (pre-existing or new-onset). The survey highlights the considerable heterogeneity of the type of anticoagulation, with 25% of the centres never using the non-vitamin K antagonist oral anticoagulants (NOACs) in this setting, as well the timing of oral anticoagulation initiation, the use and dosing of low-molecular-weight heparins, and the duration of anticoagulation when sinus rhythm is restored. One-third of the centres stated that they perceived that the risk of major pericardial bleeding requiring pericardiocentesis was higher when NOACs were used compared with vitamin K antagonists. Overall, the responding centres estimated the incidence of major pericardial haemorrhage to be 2.4%. More data are needed to inform practice guidelines in this field. PMID:27358360

  15. Attenuation effect of Abnormal Savda Munziq on liver and heart toxicity caused by chemotherapy in mice

    PubMed Central

    AIKEMU, AINIWAER; AMAT, NURMUHAMAT; YUSUP, ABDIRYIM; SHAN, LIANLIAN; QI, XINWEI; UPUR, HALMURAT

    2016-01-01

    Abnormal Savda Munziq (ASMq), an Uighur medicine formula commonly used in the treatment of cancer, has been speculated to possess antioxidative and antiproliferative effects, and to regulate immune activity. The present study was designed to systematically elucidate the toxicity-reducing activity of ASMq in mice undergoing combination chemotherapy with doxorubicin and 5-fluorouracil (5-FU). The mice were divided into normal (saline, 10 ml/kg) and doxorubicin + 5-FU groups (doxorubicin, 2.5 mg/kg; 5-FU, 10 mg/kg on alternate days). In addition, three groups received different doses of ASMq (2, 4 and 8 g/kg), in addition to doxorubicin (2.5 mg/kg) and 5-FU (10 mg/kg) treatment on alternate days. The histology of the heart and liver, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, malondialdehyde (MDA) concentrations in heart homogenate, and various biochemical parameters of the liver were evaluated. Compared with the normal control group, ASMq dose-dependently improved a number of variables, including body weight, liver index, transaminase and total protein, and partially normalized liver and cardiac pathology. ASMq restored activities of defense antioxidant enzymes SOD and GSH-Px towards normal levels, and decreased MDA concentration in dose-dependent manner. These results demonstrated that ASMq provides significant protection against doxorubicin + 5-FU combination induced hepatotoxicity and cardiotoxicity. Further studies are required to determine the effects of ASMq against doxorubicin + 5-FU-induced toxicity during chemotherapy in vivo. PMID:27347066

  16. Bleeding Risk and Antithrombotic Strategy in Patients With Sinus Rhythm and Heart Failure With Reduced Ejection Fraction Treated With Warfarin or Aspirin.

    PubMed

    Ye, Siqin; Cheng, Bin; Lip, Gregory Y H; Buchsbaum, Richard; Sacco, Ralph L; Levin, Bruce; Di Tullio, Marco R; Qian, Min; Mann, Douglas L; Pullicino, Patrick M; Freudenberger, Ronald S; Teerlink, John R; Mohr, J P; Graham, Susan; Labovitz, Arthur J; Estol, Conrado J; Lok, Dirk J; Ponikowski, Piotr; Anker, Stefan D; Thompson, John L P; Homma, Shunichi

    2015-09-15

    We sought to assess the performance of existing bleeding risk scores, such as the Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly (HAS-BLED) score or the Outpatient Bleeding Risk Index (OBRI), in patients with heart failure with reduced ejection fraction (HFrEF) in sinus rhythm (SR) treated with warfarin or aspirin. We calculated HAS-BLED and OBRI risk scores for 2,305 patients with HFrEF in SR enrolled in the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction trial. Proportional hazards models were used to test whether each score predicted major bleeding, and comparison of different risk scores was performed using Harell C-statistic and net reclassification improvement index. For the warfarin arm, both scores predicted bleeding risk, with OBRI having significantly greater C-statistic (0.72 vs 0.61; p = 0.03) compared to HAS-BLED, although the net reclassification improvement for comparing OBRI to HAS-BLED was not significant (0.32, 95% confidence interval [CI] -0.18 to 0.37). Performance of the OBRI and HAS-BLED risk scores was similar for the aspirin arm. For participants with OBRI scores of 0 to 1, warfarin compared with aspirin reduced ischemic stroke (hazard ratio [HR] 0.51, 95% CI 0.26 to 0.98, p = 0.042) without significantly increasing major bleeding (HR 1.24, 95% CI 0.66 to 2.30, p = 0.51). For those with OBRI score of ≥2, there was a trend for reduced ischemic stroke with warfarin compared to aspirin (HR 0.56, 95% CI 0.27 to 1.15, p = 0.12), but major bleeding was increased (HR 4.04, 95% CI 1.99 to 8.22, p <0.001). In conclusion, existing bleeding risk scores can identify bleeding risk in patients with HFrEF in SR and could be tested for potentially identifying patients with a favorable risk/benefit profile for antithrombotic therapy with warfarin. PMID:26189039

  17. Noise Effects on the Complex Patterns of Abnormal Heartbeats

    SciTech Connect

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Ivanov, Plamen Ch.; Glass, Leon; Goldberger, Ary L.; Stanley, H. Eugene

    2001-08-06

    Patients at high risk for sudden death often exhibit complex heart rhythms in which abnormal heartbeats are interspersed with normal heartbeats. We analyze such a complex rhythm in a single patient over a 12-h period and show that the rhythm can be described by a theoretical model consisting of two interacting oscillators with stochastic elements. By varying the magnitude of the noise, we show that for an intermediate level of noise, the model gives best agreement with key statistical features of the dynamics.

  18. THE INTRINSIC RHYTHM OF THE TURTLE'S HEART STUDIED WITH A NEW TYPE OF CHRONOGRAPH, TOGETHER WITH THE EFFECTS OF SOME DRUGS AND HORMONES.

    PubMed

    Loomis, A L; Harvey, E N; Macrae, C

    1930-09-20

    A chronograph is described for recording continuously the rates of many different kinds of rhythmic processes over long time periods. The rate is read directly from the length of a line of ink, drawn by a moving pen. Rates of beat of excised turtle's hearts in Ringer's solution have been recorded at 25 degrees C. under constant conditions of temperature, pH, and oxygen supply for periods of 36 hours. Regular periodic variations in the fundamental rhythm are figured, as well as rates of extraordinary constancy. The effects of adrenalin, ephedrin, thyroxin, alpha and beta pituitary hormone insulin, nicotin, and atropin are described in the text. PMID:19872568

  19. Abnormal Abdominal Aorta Hemodynamics Are Associated with Necrotizing Enterocolitis in Infants with Hypoplastic Left Heart Syndrome

    PubMed Central

    Miller, Thomas A.; Minich, L. LuAnn; Lambert, Linda M.; Joss-Moore, Lisa; Puchalski, Michael D.

    2013-01-01

    Background The risk of necrotizing enterocolitis (NEC) in association with congenital heart disease is highest in patients with hypoplastic left heart syndrome (HLHS). Within the HLHS population, however, risk factors for NEC remain debated. We hypothesized that some infants with HLHS have vascular changes that contribute to gut hypoperfusion, independent of diastolic run-off and low cardiac output. Methods We analyzed the abdominal aorta pulsatility index and right ventricular function on routine pre-operative and post-operative echocardiograms for all infants who underwent stage I palliation for HLHS from January 2007 to January 2012. The echocardiography findings and clinical course were compared between those with and those without an episode of NEC. Results Of the 61 cases reviewed, 11 (18%) developed NEC during a mean follow-up of 3.8 ±1.3 years. Those with NEC had a lower abdominal aorta pulsatility index compared to those without NEC both on stage I pre-operative (3.38 ±0.15 vs. 3.89 ±0.09, p<0.05) and post-operative echocardiograms (2.21 ±0.28 vs. 3.05 ±0.78, p=0.01) despite similar ventricular function and operative risk. Conclusions Abdominal aorta Doppler pulsations are lower in patients with HLHS whose clinical course is complicated by NEC. This finding suggests that the systemic vasculature in a subset of neonates with HLHS may be inherently abnormal. Further investigation is warranted to determine if this is secondary to structural changes in the mesenteric and/or systemic vasculature. PMID:24154504

  20. Diurnal 24-hour rhythm in ambulatory heart rate variability during the day shift in rotating shift workers.

    PubMed

    Yoshizaki, Takahiro; Kawano, Yukari; Tada, Yuki; Hida, Azumi; Midorikawa, Toru; Hasegawa, Kohe; Mitani, Takeshi; Komatsu, Taiki; Togo, Fumiharu

    2013-06-01

    Circadian variation in cardiac autonomic nervous system activity and behavior during the day shifts of shift workers has not hitherto been clarified. This study examined diurnal 24-h variation in heart rate variability (HRV), sleep-wake cycle, physical activity, and food intake during the day shift in rotating shift workers. The subjects were female nurses and caregivers working at a health care facility (14 day workers and 13 rotating shift workers). Each subject was asked to undergo 24-h electrocardiograph and step count recordings. Coarse graining spectral analysis was used for approximately 10-min segments of HRV (600 beats) to derive the total power (TOT: >0.04 Hz), integrated power in the low-frequency (LF: 0.04-0.15 Hz) and high-frequency (HF: >0.15 Hz) ranges, the ratio of HF power to TOT (HF nu), and the ratio of LF power to HF power (LF/HF). Double cosinor analysis was used to obtain 24-h and 12-h period variations in variables of HRV and physical activity. While no difference was found in the acrophases of either period for step counts or in the 12-h period of HRV variables between the groups, the acrophases of the 24-h period for HRV variables were delayed by 1.3 to 5.5 h in rotating shift workers, and their differences in HF power, HF nu, and LF/HF reached a significant level (p < 0.05). On the days of the experiment, retiring time, waking up time, total time in bed, sleep efficiency, and mealtimes and energy intake for each diet did not differ between the groups. These results suggest that there is a possibility of an abnormal phase angle between circadian variation in cardiac autonomic nervous system activity and the sleep-wake cycle during the day shift in shift workers. PMID:23735502

  1. Continuous exposure to a novel stressor based on water aversion induces abnormal circadian locomotor rhythms and sleep-wake cycles in mice.

    PubMed

    Miyazaki, Koyomi; Itoh, Nanako; Ohyama, Sumika; Kadota, Koji; Oishi, Katsutaka

    2013-01-01

    Psychological stressors prominently affect diurnal rhythms, including locomotor activity, sleep, blood pressure, and body temperature, in humans. Here, we found that a novel continuous stress imposed by the perpetual avoidance of water on a wheel (PAWW) affected several physiological diurnal rhythms in mice. One week of PAWW stress decayed robust circadian locomotor rhythmicity, while locomotor activity was evident even during the light period when the mice are normally asleep. Daytime activity was significantly upregulated, whereas nighttime activity was downregulated, resulting in a low amplitude of activity. Total daily activity gradually decreased with increasing exposure to PAWW stress. The mice could be exposed to PAWW stress for over 3 weeks without adaptation. Furthermore, continuous PAWW stress enhanced food intake, but decreased body weight and plasma leptin levels, indicating that sleep loss and PAWW stress altered the energy balance in these mice. The diurnal rhythm of corticosterone levels was not severely affected. The body temperature rhythm was diurnal in the stressed mice, but significantly dysregulated during the dark period. Plasma catecholamines were elevated in the stressed mice. Continuous PAWW stress reduced the duration of daytime sleep, especially during the first half of the light period, and increased nighttime sleepiness. Continuous PAWW stress also simultaneously obscured sleep/wake and locomotor activity rhythms compared with control mice. These sleep architecture phenotypes under stress are similar to those of patients with insomnia. The stressed mice could be entrained to the light/dark cycle, and when they were transferred to constant darkness, they exhibited a free-running circadian rhythm with a timing of activity onset predicted by the phase of their entrained rhythms. Circadian gene expression in the liver and muscle was unaltered, indicating that the peripheral clocks in these tissues remained intact. PMID:23383193

  2. Oral contraceptives alter circadian rhythm parameters of cortisol, melatonin, blood pressure, heart rate, skin blood flow, transepidermal water loss, and skin amino acids of healthy young women.

    PubMed

    Reinberg, A E; Touitou, Y; Soudant, E; Bernard, D; Bazin, R; Mechkouri, M

    1996-08-01

    Sixteen healthy women users and nonusers of oral contraceptives (OC) volunteered to document a set of circadian rhythms. Nine were taking OC providing ethynyl estradiol (0.03-0.05 mg/24h, 21 days/month) combined with DL- or L-norgestrel or norethisterone. There was no group difference (p > 0.05) in median age (22 years), weight (57 kg), and height (162) cm). Data were obtained at fixed hours, 5 times/24h, during a 48-h span, in November. (Day activity from approximately 08:00 to approximately 23:00 h and night rest). Environmental conditions were controlled, using air-conditioned rooms of constant temperature (26 degrees +/- 0.5) and relative humidity 45% +/- 1. Both cosinor and ANOVA were used for statistical analyses. All circadian rhythms were validated with one exception: that of salivary melatonin was not detected in OC users. The 24h mean (M) exhibited group differences for certain variables: M was greater in OC than non-OC users for systolic blood pressure (p < 0.0001), heart rate (p < 0.01), skin blood flow (p < 0.04), and transepidermal water loss (p < 0.02). M was lower in OC than non-OC users in salivary cortisol (p < 0.04) and skin amino acids (p < 0.003). No group difference was detected in any other documented rhythms: diastolic blood pressure, grip strength of both hands, oral temperature, self-rated fatigue, and the skin variables of urea, lactate, triglycerides, and acid phosphatase activity. PMID:8874983

  3. Heart Failure and Mitochondrial Dysfunction: The Role of Mitochondrial Fission/Fusion Abnormalities and New Therapeutic Strategies

    PubMed Central

    Knowlton, A. A.; Chen, Le; Malik, Zulfiqar A.

    2013-01-01

    The treatment of heart failure has evolved during the last thirty years with recognition of neurohormonal activation and the effectiveness of its inhibition in improving quality of life and survival. Over the last twenty years there has been a revolution in the investigation of the mitochondrion with the development of new techniques and the finding that mitochondria are connected in networks and undergo constant division (fission) and fusion, even in cardiac myocytes. This has led to new molecular and cellular discoveries in heart failure, which offer the potential for the development of new molecular-based therapies. Reactive oxygen species (ROS) are an important cause of mitochondrial and cellular injury in heart failure, but there are other abnormalities, such as depressed mitochondrial fusion, that may eventually become targets of at least episodic treatment. The overall need for mitochondrial fission/fusion balance may preclude sustained change in either fission or fusion. In this review we will discuss current heart failure therapy and its impact on the mitochondria. In addition we will review some of the new drug targets under development. There is potential for effective, novel therapies for heart failure to arise from new molecular understanding. PMID:23884159

  4. Spectrum of congenital heart defects and extracardiac malformations associated with chromosomal abnormalities: results of a seven year necropsy study

    PubMed Central

    Tennstedt, C; Chaoui, R; Korner, H; Dietel, M

    1999-01-01

    associated with other cardiovascular and extracardiac malformations, as well as with chromosome anomalies. Complex heart defects such as AVSD, HLH, and DORV are frequent in fetuses, as they often lead to spontaneous abortion or stillbirth or, after prenatal diagnosis, to deliberate termination of pregnancy.


Keywords: congenital heart defects; extracardiac malformations; chromosomal abnormalities; necropsy examination PMID:10377306

  5. A roadmap to improve the quality of atrial fibrillation management: proceedings from the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference.

    PubMed

    Kirchhof, Paulus; Breithardt, Günter; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Calvert, Melanie; Christoffels, Vincent; Crijns, Harry; Dobrev, Dobromir; Ellinor, Patrick; Fabritz, Larissa; Fetsch, Thomas; Freedman, S Ben; Gerth, Andrea; Goette, Andreas; Guasch, Eduard; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Haeusler, Karl Georg; Heidbüchel, Hein; Heinrich-Nols, Jutta; Hidden-Lucet, Francoise; Hindricks, Gerd; Juul-Möller, Steen; Kääb, Stefan; Kappenberger, Lukas; Kespohl, Stefanie; Kotecha, Dipak; Lane, Deirdre A; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Münzel, Felix; Nabauer, Michael; Nielsen, Jens C; Oeff, Michael; Oldgren, Jonas; Oto, Ali; Piccini, Jonathan P; Pilmeyer, Art; Potpara, Tatjana; Ravens, Ursula; Reinecke, Holger; Rostock, Thomas; Rustige, Joerg; Savelieva, Irene; Schnabel, Renate; Schotten, Ulrich; Schwichtenberg, Lars; Sinner, Moritz F; Steinbeck, Gerhard; Stoll, Monika; Tavazzi, Luigi; Themistoclakis, Sakis; Tse, Hung Fat; Van Gelder, Isabelle C; Vardas, Panagiotis E; Varpula, Timo; Vincent, Alphons; Werring, David; Willems, Stephan; Ziegler, André; Lip, Gregory Y H; Camm, A John

    2016-01-01

    At least 30 million people worldwide carry a diagnosis of atrial fibrillation (AF), and many more suffer from undiagnosed, subclinical, or 'silent' AF. Atrial fibrillation-related cardiovascular mortality and morbidity, including cardiovascular deaths, heart failure, stroke, and hospitalizations, remain unacceptably high, even when evidence-based therapies such as anticoagulation and rate control are used. Furthermore, it is still necessary to define how best to prevent AF, largely due to a lack of clinical measures that would allow identification of treatable causes of AF in any given patient. Hence, there are important unmet clinical and research needs in the evaluation and management of AF patients. The ensuing needs and opportunities for improving the quality of AF care were discussed during the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference in Nice, France, on 22 and 23 January 2015. Here, we report the outcome of this conference, with a focus on (i) learning from our 'neighbours' to improve AF care, (ii) patient-centred approaches to AF management, (iii) structured care of AF patients, (iv) improving the quality of AF treatment, and (v) personalization of AF management. This report ends with a list of priorities for research in AF patients. PMID:26481149

  6. The role of the Arrhythmia Team, an integrated, multidisciplinary approach to treatment of patients with cardiac arrhythmias: results of the European Heart Rhythm Association survey.

    PubMed

    Fumagalli, Stefano; Chen, Jian; Dobreanu, Dan; Madrid, Antonio Hernandez; Tilz, Roland; Dagres, Nikolaos

    2016-04-01

    Management of patients with cardiac arrhythmias is increasingly complex because of continuous technological advance and multifaceted clinical conditions associated with ageing of the population, the presence of co-morbidities and the need for polypharmacy. The aim of this European Heart Rhythm Association Scientific Initiatives Committee survey was to provide an insight into the role of the Arrhythmia Team, an integrated, multidisciplinary approach to management of patients with cardiac arrhythmias. Forty-eight centres from 18 European countries replied to the Web-based questionnaire. The presence of an Arrhythmia Team was reported by 44% of the respondents, whereas 17% were not familiar with this term. Apart from the electrophysiologist, health professionals who should belong to such teams, according to the majority of the respondents, include a clinical cardiologist, a nurse, a cardiac surgeon, a heart failure specialist, a geneticist, and a geriatrician. Its main activity should be dedicated to the management of patients with complex clinical conditions or refractory or inherited forms of arrhythmias. When present, the Arrhythmia Team was considered helpful by 95% of respondents; the majority of centres (79%) agreed that it should be implemented. The Arrhythmia Team seems to be connected to important expectations in the management of cardiac arrhythmias. The efficacy of such an integrated and multidisciplinary approach should be encouraged and tested in clinical practice. PMID:27174994

  7. Abnormal Development of Thalamic Microstructure in Premature Neonates with Congenital Heart Disease

    PubMed Central

    Paquette, Lisa B.; Votava-Smith, Jodie K.; Ceschin, Rafael; Nagasunder, Arabhi C.; Jackson, Hollie A.; Blüml, Stefan; Wisnowski, Jessica L.; Panigrahy, Ashok

    2015-01-01

    Background and Purpose Preterm birth is associated with alteration in cortico-thalamic development, which underlies poor neurodevelopmental outcomes. Our hypothesis was that preterm neonates with CHD would demonstrate abnormal thalamic microstructure when compared to critically ill neonates without CHD. A secondary aim was to identify any association between thalamic microstructural abnormalities and peri-operative clinical variables. Material and Methods We compared thalamic DTI measurements in 21 preterm neonates with CHD to two cohorts of neonates without CHD: 28 term and 27 preterm neonates, identified from the same neonatal intensive care unit. Comparison was made with three other selected white matter regions using ROI manual based measurements. Correlation was made with post-conceptional age and peri-operative clinical variables. Results In preterm neonates with CHD, there were age-related differences in thalamic diffusivity (axial and radial) compared to the preterm and term non-CHD group, in contrast to no differences in anisotropy. Contrary to our hypothesis, abnormal thalamic and optic radiation microstructure was most strongly associated with an elevated first arterial blood gas pO2 and elevated pre-operative arterial blood gas pH (p<0.05). Conclusion Age-related thalamic microstructural abnormalities were observed in preterm neonates with CHD. Perinatal hyperoxemia and increased peri-operative serum pH was associated with abnormal thalamic microstructure in preterm neonates with CHD. This study emphasizes the vulnerability of thalamo-cortical development in the preterm neonate with CHD. PMID:25608695

  8. Sugar-sweetened beverages and prevalence of the metabolically abnormal phenotype in the Framingham Heart Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to examine the relationship between usual sugar-sweetened beverage (SSB) consumption and prevalence of abnormal metabolic health across body mass index (BMI) categories. The metabolic health of 6,842 non-diabetic adults was classified using cross-sectional data from the...

  9. A portable fetal heart monitor and its adaption to the detection of certain prenatal abnormalities

    NASA Technical Reports Server (NTRS)

    Zahorian, Stephen A.

    1994-01-01

    There were three primary objectives for this task: (1) The investigation of the feasibility of making the fetal heart rate monitor portable, using a laptop computer; (2) Improvements in the signal processing for the monitor; and (3) Implementation of a real-time hardware software system. These tasks have been completed as discussed in the following section.

  10. Abnormalities of capillary microarchitecture in a rat model of coronary ischemic congestive heart failure

    PubMed Central

    Chen, Jiqiu; Yaniz-Galende, Elisa; Kagan, Heather J.; Liang, Lifan; Hekmaty, Saboor; Giannarelli, Chiara

    2015-01-01

    The aim of the present study is to explore the role of capillary disorder in coronary ischemic congestive heart failure (CHF). CHF was induced in rats by aortic banding plus ischemia-reperfusion followed by aortic debanding. Coronary arteries were perfused with plastic polymer containing fluorescent dye. Multiple fluorescent images of casted heart sections and scanning electric microscope of coronary vessels were obtained to characterize changes in the heart. Cardiac function was assessed by echocardiography and in vivo hemodynamics. Stenosis was found in all levels of the coronary arteries in CHF. Coronary vasculature volume and capillary density in remote myocardium were significantly increased in CHF compared with control. This occurred largely in microvessels with a diameter of ≤3 μm. Capillaries in CHF had a tortuous structure, while normal capillaries were linear. Capillaries in CHF had inconsistent diameters, with assortments of narrowed and bulged segments. Their surfaces appeared rough, potentially indicating endothelial dysfunction in CHF. Segments of main capillaries between bifurcations were significantly shorter in length in CHF than in control. Transiently increasing preload by injecting 50 μl of 30% NaCl demonstrated that the CHF heart had lower functional reserve; this may be associated with congestion in coronary microcirculation. Ischemic coronary vascular disorder is not limited to the main coronary arteries, as it occurs in arterioles and capillaries. Capillary disorder in CHF included stenosis, deformed structure, proliferation, and roughened surfaces. This disorder in the coronary artery architecture may contribute to the reduction in myocyte contractility in the setting of heart failure. PMID:25659485

  11. 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.

    PubMed

    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

  12. 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

    PubMed Central

    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

  13. [Gender differences of the influence of an "aggressive" computer game on the variability of the heart rhythm].

    PubMed

    Stepanian, L S; Grigorian, V G; Stepanian, A Iu

    2010-01-01

    The influence of virtual aggressogenic environment on psychoemotional sphere of male and female teenagers with different levels of personal aggression was studied by characteristics of the heart rate. The exposure to the aggressogenic factors produced a change of the centralized control for the autonomic control in female and male teenagers with the high level of aggression and females with the low level of aggression. Male teenagers with the low level of aggression displayed the prevalence of the centralized control. Thus, the influence of exposure of teenagers to the virtual aggressogenic environment was shown to be ambiguous depending on the level of the level of personal aggression and gender. PMID:20469589

  14. Preference for oral anticoagulation therapy for patients with atrial fibrillation in Europe in different clinical situations: results of the European Heart Rhythm Association Survey.

    PubMed

    Larsen, Torben Bjerregaard; Potpara, Tatjana; Dagres, Nikolaos; Proclemer, Alessandro; Sciarrafia, Elena; Blomström-Lundqvist, Carina

    2015-05-01

    The purpose of this European Heart Rhythm Association Survey was to assess the clinical practice in relation to the use of oral anticoagulation therapy for patients with atrial fibrillation (AF) in Europe. Of special interest were patients undergoing percutaneous coronary intervention (PCI), cardioversion procedures, catheter ablation, surgery, and those suffering from anticoagulation-related bleeding. Of 38 responding centres, non-vitamin K antagonist oral anticoagulants (NOACs) were used for stroke prophylaxis and were preferred (33.3%) or considered equal (48.5%) to vitamin K antagonists (VKAs). Only 3% did not use NOACs at all. There were some practice differences regarding the use of NOACs in combination with dual antiplatelet therapy in AF patients undergoing PCI, and only 12% preferred using NOACs in this setting. Bare metal stents were preferred rather than drug-eluting stents in AF patients at high bleeding risk. There were clear practice differences between centres regarding the use of triple therapy. Most of the major bleeding events would be handled using symptomatic and supportive measures (e.g. mechanical compression, fluid replacement, blood transfusion, prothrombin complex concentrate, or recombinant Factor VIIa). More than 80% of the centres offer either VKA or NOAC for at least 3 weeks before and after cardioversion and 70% offer either VKA or NOAC before and after AF catheter ablation. Patients treated with an NOAC were routinely re-assed in most centres. PMID:25926476

  15. The European Heart Rhythm Association Practical Guide on the Use of New Oral Anticoagulants in Patients with Non-valvular Atrial Fibrillation – A Brief Summary

    PubMed Central

    Kirchhof, Paulus

    2013-01-01

    New oral anticoagulants (NOACs) are an alternative to vitamin K antagonists (VKAs) in the prevention of stroke in patients with non-valvular atrial fibrillation (AF). The European Heart Rhythm Association (EHRA) has produced a practical guide to detail the use of NOACs in clinical practice. The guide includes a practical start-up and follow-up scheme, emphasising the importance of strict adherence to the regimen – the anticoagulant effect drops rapidly after 12–24 hours. There is also guidance on how to measure the anticoagulant effect of NOACs, switching between anticoagulant regimes and dealing with dosing errors. Physicians will have to consider the pharmacokinetic effect of drugs and co-morbidities when prescribing NOACs – plasma levels of NOACs may be affected by P-glycoprotein (P-gp) substrates, as well as cytochrome P450 (CYP3A4) inducers or inhibitors. In patients with chronic kidney disease, reduced doses of NOACs may be indicated. Guidance is also given on the management of bleeding complications, and the cessation and reinitiation of NOACs in patients undergoing surgical interventions. Finally, the use of NOACs in specific clinical situations is considered; these include patients with AF and coronary artery disease (CAD), patients presenting with acute stroke while taking NOACs and patients with cancer. PMID:26835051

  16. [Autonomic regulation in patients with panic attacks based on longitudinal study data on the variability of the heart rhythm].

    PubMed

    Khaspekova, N B; Diukova, G M; Tumalaeva, Z N; Alieva, Kh K

    1999-01-01

    During a repeated study in recumbent position as well as during 48-hour monitoring of the indices of variability of RR intervals of ECG (MDRR) in patients with panic attacks (PA) a stable dominance of VLF (0.07-0.01 Hz) and rigidity of the spectrum typical for patients with panic attacks (PA) in period between the attacks was found. Prevalence of fear emotions as well as accompanying hypothalamic insufficiency were also associated with a decrease of HF. In prodromic period, in attack and after it, there was no dynamics in the frequency of heart's contractions, but there was a sharp increase of MDRR. In prodromic period VLF and LF considerably increased, while HF decreased. In a moment of a panic attack LF and HF continued to increase, while VLF significantly lowered. Activation of vasomotor (LF), vagal (HF) and cerebral (VLF) mechanisms was maintained during 5 minutes of the study after PA completion with a clear predominance of LF component. PMID:10441851

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

    PubMed

    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

  18. Normal and abnormal consequences of apoptosis in the human heart: from postnatal morphogenesis to paroxysmal arrhythmias.

    PubMed Central

    James, T. N.

    1994-01-01

    Apoptosis and necrosis are two distinctly different forms of cell death and both occur in the human heart. In contrast to necrosis, apoptosis is not associated with inflammation and there are two reasons for this. The apoptotic cell does not swell or rupture prior to its being engulfed by either a macrophage or even a neighboring like cell. And the phagocytosis occurs with unusual rapidity. Apoptosis, also thought of as cell suicide, is a tidy way of removing cells no longer useful, in essence a form of selective deletion. These features make apoptosis a valuable component of morphogenesis, mediation of hormonal and immunological responses, and the homeostatic balance between hypertrophy and atrophy or involution. In the human heart apoptosis has been found in the sinus node of patients with the long QT syndrome. It most likely participates in the important postnatal morphogenesis of the sinus node, AV (atrioventricular) node and His bundle. Apoptosis may also participate in the genesis and pathophysiology of cardiomyopathy, paroxysmal arrhythmias or conduction disturbances (some of which may be responsible for sudden death), focal fibromuscular dysplasia of small coronary arteries, hereditary medial degeneration of the tunica media of coronary arteries, and arrhythmogenic right ventricular dysplasia. The possible role of apoptosis in numerous other changes in the human heart merit future investigation, among them being the pathogenesis of atherosclerosis and mechanisms of ageing in the myocardium. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:7974966

  19. Abnormal veins around the heart with the closure of the coronary sinus ostium.

    PubMed

    Ishizawa, Akimitsu; Suzuki, Ryoji; Zhou, Ming; Abe, Hiroshi

    2016-06-01

    In a cadaveric dissection course at Akita University Graduate School of Medicine in 2014, we observed abnormal veins in a 72-year-old male who died of prostate cancer. The abnormality consisted of the following: closure of the opening of the coronary sinus (closure of the coronary sinus ostium), a persistent left superior vena cava (Lsvc), and a postaortic left brachiocephalic vein (Palbv). The shunt between the coronary sinus and left atrium was not observed. The blood of the coronary sinus flowed into an oblique vein of the left atrium, which was wide and reverse-funnel shaped, penetrated the pericardial sac then continued to the Lsvc. The anastomotic veins between the Lsvc and the (right) superior vena cava were seen to consist of two veins as follows: one was a left brachiocephalic vein, the other a dorsal postaortic left brachiocephalic vein (dorsal Palbv). The dorsal Palbv passed dorsally on the ligamentum arteriosum, and then passed between the ascending aorta and the trachea. The dorsal Palbv was thicker than the left brachiocephalic vein. We discuss the process of formation of these variations. PMID:26329835

  20. A neural network learned information measures for heart motion abnormality detection

    NASA Astrophysics Data System (ADS)

    Nambakhsh, M. S.; Punithakumar, Kumaradevan; Ben Ayed, Ismail; Goela, Aashish; Islam, Ali; Peters, Terry; Li, Shuo

    2011-03-01

    In this study, we propose an information theoretic neural network for normal/abnormal left ventricular motion classification which outperforms significantly other recent methods in the literature. The proposed framework consists of a supervised 3-layer artificial neural network (ANN) which uses hyperbolic tangent sigmoid and linear transfer functions for hidden and output layers, respectively. The ANN is fed by information theoretic measures of left ventricular wall motion such as Shannon's differential entropy (SDE), Rényi entropy and Fisher information, which measure global information of subjects distribution. Using 395×20 segmented LV cavities of short-axis magnetic resonance images (MRI) acquired from 48 subjects, the experimental results show that the proposed method outperforms Support Vector Machine (SVM) and thresholding based information theoretic classifiers. It yields a specificity equal to 90%, a sensitivity of 91%, and a remarkable Area Under Curve (AUC) for Receiver Operating Characteristic (ROC), equal to 93.2%.

  1. Assessment of Structural and Functional Abnormalities of the Myocardium and the Ascending Aorta in Fetus with Hypoplastic Left Heart Syndrome

    PubMed Central

    Jiang, Yan; Xu, Yali; Tang, Jinliang; Xia, Hongmei

    2016-01-01

    Aims. To detect anatomical and intrinsic histopathological features of the ascending aorta and left ventricular (LV) myocardium and evaluate right ventricular (RV) function in fetuses with hypoplastic left heart syndrome (HLHS). Methods. Twenty-five fetuses diagnosed with HLHS were followed up in the antenatal and postpartum periods. 12 necropsy heart specimens were analyzed for morphological and histological changes. Results. Prenatal echocardiography and pathologic anatomy displayed the typical characteristics of HLHS as a severe underdevelopment of the LV in the form of mitral stenosis or atresia or as aortic atresia or stenosis, with a decreased ratio of aortic diameter to pulmonary artery diameter (median of 0.49 with a range of 0.24 to 0.69, p ≤ 0.001) and a higher ratio of RV diameter to LV diameter (median of 2.44 with a range of 1.33 to 6.25, p ≤ 0.001). The RV volume, stroke volume, and cardiac output in HLHS fetuses were increased compared with the gestational age-matched normal controls (p < 0.01). Histological changes in the 12 HLHS specimens included LV myocardial fibrosis, aortic elastic fragmentation, and fibrosis. Conclusions. In addition to severe anatomical deformity, distinct histological abnormalities in the LV myocardium and aortic wall were identified in the fetuses with HLHS. RV function damage may be potentially exists. PMID:26981527

  2. Heart rate, conduction and ultrasound abnormalities in adults with joint hypermobility syndrome/Ehlers-Danlos syndrome, hypermobility type.

    PubMed

    Camerota, Filippo; Castori, Marco; Celletti, Claudia; Colotto, Marco; Amato, Silvia; Colella, Alessandra; Curione, Mario; Danese, Chiara

    2014-07-01

    Joint hypermobility syndrome (JHS) and Ehlers-Danlos syndrome, hypermobility type (EDS-HT) are two clinically overlapping heritable connective tissue disorders strongly associating with pain, fatigue and other secondary aspects. Though not considered a diagnostic criterion for most EDS subtypes, cardiovascular involvement is a well-known complication in EDS. A case-control study was carried out on 28 adults with JHS/EDS-HT diagnosed according to current criteria, compared to 29 healthy subjects evaluating resting electrocardiographic (ECG), 24-h ECG and resting heart ultrasound data. Results obtained in the ECG studies showed a moderate excess in duration of the PR interval and P wave, an excess of heart conduction and rate abnormalities and an increased rate of mitral and tricuspid valve insufficiency often complicating with "true" mitral valve prolapse in the ecocardiographic study. These variable ECG subclinical anomalies reported in our sample may represent the resting surrogate of such a subnormal cardiovascular response to postural changes that are known to be present in patients with JHS/EDS-HT. Our findings indicate the usefulness of a full cardiologic evaluation of adults with JHS/EDS-HT for the correct management. PMID:24752348

  3. Electrocardiographic abnormalities and cardiac arrhythmias in chronic obstructive pulmonary disease.

    PubMed

    Goudis, Christos A; Konstantinidis, Athanasios K; Ntalas, Ioannis V; Korantzopoulos, Panagiotis

    2015-11-15

    Chronic obstructive pulmonary disease (COPD) is independently associated with an increased burden of cardiovascular disease. Besides coronary artery disease (CAD) and congestive heart failure (CHF), specific electrocardiographic (ECG) abnormalities and cardiac arrhythmias seem to have a significant impact on cardiovascular prognosis of COPD patients. Disturbances of heart rhythm include premature atrial contractions (PACs), premature ventricular contractions (PVCs), atrial fibrillation (AF), atrial flutter (AFL), multifocal atrial tachycardia (MAT), and ventricular tachycardia (VT). Of note, the identification of ECG abnormalities and the evaluation of the arrhythmic risk may have significant implications in the management and outcome of patients with COPD. This article provides a concise overview of the available data regarding ECG abnormalities and arrhythmias in these patients, including an elaborated description of the underlying arrhythmogenic mechanisms. The clinical impact and prognostic significance of ECG abnormalities and arrhythmias in COPD as well as the appropriate antiarrhythmic therapy and interventions in this setting are also discussed. PMID:26218181

  4. Usefulness of verapamil for congestive heart failure associated with abnormal left ventricular diastolic filling and normal left ventricular systolic performance

    SciTech Connect

    Setaro, J.F.; Zaret, B.L.; Schulman, D.S.; Black, H.R.; Soufer, R. )

    1990-10-15

    Normal left ventricular systolic performance with impaired left ventricular diastolic filling may be present in a substantial number of patients with congestive heart failure (CHF). To evaluate the effect of oral verapamil in this subset, 20 men (mean age 68 +/- 5 years) with CHF, intact left ventricular function (ejection fraction greater than 45%) and abnormal diastolic filling (peak filling rate less than 2.5 end-diastolic volumes per second (edv/s)) were studied in a placebo-controlled, double-blind 5-week crossover trial. All patients underwent echocardiography to rule out significant valvular disease, and thallium-201 stress scintigraphy to exclude major active ischemia. Compared to baseline values, verapamil significantly improved exercise capacity by 33% (13.9 +/- 4.3 vs 10.7 +/- 3.4 minutes at baseline) and peak filling rate by 30% (2.29 +/- 0.54 vs 1.85 +/- 0.45 edv/s at baseline) (all p less than 0.05). Placebo values were 12.3 +/- 4.0 minutes and 2.16 +/- 0.48 edv/s, respectively (difference not significant for both). Improvement from baseline in an objective clinico-radiographic heart failure score (scale 0 to 13) was significantly greater with verapamil compared to placebo (median improvement in score: 3 vs 1, p less than 0.01). Mean ejection fraction and systolic blood pressure were unchanged from baseline; diastolic blood pressure and heart rate decreased to a small degree. Verapamil may have therapeutic efficacy in patients with CHF, preserved systolic function and impaired diastolic filling.

  5. Quality of Anticoagulation Control in Preventing Adverse Events in Heart Failure Patients in Sinus Rhythm: A Warfarin Aspirin Reduced Cardiac Ejection Fraction Trial (WARCEF) Substudy

    PubMed Central

    Homma, Shunichi; Thompson, John L.P.; Qian, Min; Ye, Siqin; Di Tullio, Marco R.; Lip, Gregory Y.H.; Mann, Douglas L.; Sacco, Ralph L.; Levin, Bruce; Pullicino, Patrick M.; Freudenberger, Ronald S.; Teerlink, John R.; Graham, Susan; Mohr, J.P.; Labovitz, Arthur J.; Buchsbaum, Richard; Estol, Conrado J.; Lok, Dirk J.; Ponikowski, Piotr; Anker, Stefan D.

    2015-01-01

    Background The aim of this study is to examine the relationship between time in therapeutic range (TTR) and clinical outcomes in heart failure (HF) patients in sinus rhythm (SR) treated with warfarin. Methods and Results We used data from the Warfarin vs. Aspirin in Reduced Cardiac Ejection Fraction Trial (WARCEF) to assess the relationship of TTR with the WARCEF primary outcome (ischemic stroke, intracerebral hemorrhage, or death); with death alone; ischemic stroke alone; major hemorrhage alone; and net clinical benefit (primary outcome and major hemorrhage combined). Multivariable Cox models were used to examine how the event risk changed with TTR and to compare the high TTR, low TTR, and aspirin patients, with TTR being treated as a time-dependent covariate. 2,217 patients were included in the analyses, among whom 1,067 were randomized to warfarin and 1,150 were randomized to aspirin. The median (IQR) follow-up duration was 3.6 (2.0–5.0) years. Mean (±SD) age was 61±11.3 years, with 80% being men. The mean (±SD) TTR was 57% (±28.5%). Increasing TTR was significantly associated with reduction in primary outcome (adjusted p<0.001), death alone (adjusted p=0.001), and improved net clinical benefit (adjusted p<0.001). A similar trend was observed for the other two outcomes but significance was not reached (adjusted p=0.082 for ischemic stroke, adjusted p=0.109 for major hemorrhage). Conclusions In HF patients in SR, increasing TTR is associated with better outcome and improved net clinical benefit. Patients in whom good quality anticoagulation can be achieved may benefit from the use of anticoagulants. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00041938. PMID:25850425

  6. 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.

    PubMed

    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. PMID:25722478

  7. Associations between Diurnal 24-Hour Rhythm in Ambulatory Heart Rate Variability and the Timing and Amount of Meals during the Day Shift in Rotating Shift Workers

    PubMed Central

    Yoshizaki, Takahiro; Midorikawa, Toru; Hasegawa, Kohe; Mitani, Takeshi; Komatsu, Taiki; Togo, Fumiharu

    2014-01-01

    It has not hitherto been clarified whether there is an association between dietary behavior and circadian variation in autonomic nervous system activity among shift workers. This study examines diurnal 24-h rhythm in heart rate variability (HRV) and dietary behavior among rotating shift workers, while taking into account the sleep-wake cycle and physical activity. The subjects were 11 female and 2 male nurses or caregivers working in a rotating 2-shift system at a health care facility. All the subjects were asked to undergo 24-h electrocardiograph and step count recordings, and to record the time of each meal and the amounts of each food and beverage consumed. Coarse graining spectral analysis was used for approximately 10-min segments of HRV to derive the total power (TOT: >0.04 Hz) of the periodic components and the integrated power of periodic components in the low-frequency (LF: 0.04–0.15 Hz) and high-frequency (HF: >0.15 Hz) ranges. Then the ratio of HF power to TOT (HF nu) and the ratio of LF power to HF power (LF/HF) were calculated to assess cardiac vagal tone and cardiac sympathovagal balance, respectively. Single cosinor analysis was used to obtain 24-h period variations in both variables of HRV. Acrophases of HF nu and LF/HF expressed in time since awakening were significantly (p<0.05) delayed for subjects having breakfast at a later time after awakening. Multivariable regression analysis indicated that the timing of breakfast, the ratio of energy intake at dinner to total energy intake, and total energy intake were correlated to the acrophases of HF nu and/or LF/HF. These results suggest that the phase angle between circadian variation in cardiac autonomic nervous system activity and the sleep-wake cycle may be associated with dietary behavior in shift workers. PMID:25211024

  8. NEUROSENSORY LINKS BETWEEN BRONCHOCONSTRICTION AND CARDIAC RHYTHM

    EPA Science Inventory

    Reports in the literature have attributed altered heart rate, heart rate variability, and rhythm to inhaled particulate matter (PM) in humans. Whereas the changes in heart rate are very small, analysis of ECG tracings indicate changes in HRV suggesting altered autonomic balance. ...

  9. [Wenckebach and his rhythm].

    PubMed

    van Gijn, Jan; Gijselhart, Joost P

    2011-01-01

    Karel Frederik Wenckebach (1864-1940) showed an aptitude for research even as a medical student in Utrecht. After graduation and a thesis on the bursa of Fabricius he worked as an assistant in the physiological laboratory. Following a stint as general practitioner in a mining community (1891-1896) he returned to Utrecht, where he could combine his practice with physiological studies, especially disturbances of the heart rhythm. In 1899, with no other recording instruments than a sphygmomanometer for tracing the radial pulse and a tuning fork for chronometry, he described the 'rhythmic arrhythmia' phenomenon: a missed beat after a given number of regular beats (mostly between three and six), followed by an intermission shorter than the interval between two regular beats. The Wenckebach rhythm is now also known as type I second-degree atrioventricular block. Wenckebach subsequently became a professor of medicine in Groningen (1901), Strasbourg (1911) and Vienna (1914-1929). PMID:22085509

  10. A sodium-glucose co-transporter 2 inhibitor empagliflozin prevents abnormality of circadian rhythm of blood pressure in salt-treated obese rats.

    PubMed

    Takeshige, Yui; Fujisawa, Yoshihide; Rahman, Asadur; Kittikulsuth, Wararat; Nakano, Daisuke; Mori, Hirohito; Masaki, Tsutomu; Ohmori, Koji; Kohno, Masakazu; Ogata, Hiroaki; Nishiyama, Akira

    2016-06-01

    Studies were performed to examine the effects of the selective sodium-glucose co-transporter 2 (SGLT2) inhibitor empagliflozin on urinary sodium excretion and circadian blood pressure in salt-treated obese Otsuka Long Evans Tokushima Fatty (OLETF) rats. Fifteen-week-old obese OLETF rats were treated with 1% NaCl (in drinking water), and vehicle (0.5% carboxymethylcellulose, n=10) or empagliflozin (10 mg kg(-1)per day, p.o., n=11) for 5 weeks. Blood pressure was continuously measured by telemetry system. Glucose metabolism and urinary sodium excretion were evaluated by oral glucose tolerance test and high salt challenge test, respectively. Vehicle-treated OLETF rats developed non-dipper type blood pressure elevation with glucose intolerance and insulin resistance. Compared with vehicle-treated animals, empagliflozin-treated OLETF rats showed an approximately 1000-fold increase in urinary glucose excretion and improved glucose metabolism and insulin resistance. Furthermore, empagliflozin prevented the development of blood pressure elevation with normalization of its circadian rhythm to a dipper profile, which was associated with increased urinary sodium excretion. These data suggest that empagliflozin elicits beneficial effects on both glucose homeostasis and hypertension in salt-replete obese states. PMID:26818652

  11. Learning Rhythms.

    ERIC Educational Resources Information Center

    Lippitt, Gordon L.

    1979-01-01

    Discusses factors which determine the quality of learning experiences. The author hypothesizes that there are learning rhythms which must be present in a balanced way for a Peak Learning Experience (PLE) to occur. Learner readiness can be stimulated by a teacher, increasing chances for a PLE. (JOW)

  12. Modulation of Serotonin Transporter Function during Fetal Development Causes Dilated Heart Cardiomyopathy and Lifelong Behavioral Abnormalities

    PubMed Central

    Noorlander, Cornelle W.; Ververs, Frederique F. T.; Nikkels, Peter G. J.; van Echteld, Cees J. A.; Visser, Gerard H. A.; Smidt, Marten P.

    2008-01-01

    Background Women are at great risk for mood and anxiety disorders during their childbearing years and may become pregnant while taking antidepressant drugs. In the treatment of depression and anxiety disorders, selective serotonin reuptake inhibitors (SSRIs) are the most frequently prescribed drugs, while it is largely unknown whether this medication affects the development of the central nervous system of the fetus. The possible effects are the product of placental transfer efficiency, time of administration and dose of the respective SSRI. Methodology/Principal Findings In order to attain this information we have setup a study in which these parameters were measured and the consequences in terms of physiology and behavior are mapped. The placental transfer of fluoxetine and fluvoxamine, two commonly used SSRIs, was similar between mouse and human, indicating that the fetal exposure of these SSRIs in mice is comparable with the human situation. Fluvoxamine displayed a relatively low placental transfer, while fluoxetine showed a relatively high placental transfer. Using clinical doses of fluoxetine the mortality of the offspring increased dramatically, whereas the mortality was unaffected after fluvoxamine exposure. The majority of the fluoxetine-exposed offspring died postnatally of severe heart failure caused by dilated cardiomyopathy. Molecular analysis of fluoxetine-exposed offspring showed long-term alterations in serotonin transporter levels in the raphe nucleus. Furthermore, prenatal fluoxetine exposure resulted in depressive- and anxiety-related behavior in adult mice. In contrast, fluvoxamine-exposed mice did not show alterations in behavior and serotonin transporter levels. Decreasing the dose of fluoxetine resulted in higher survival rates and less dramatic effects on the long-term behavior in the offspring. Conclusions These results indicate that prenatal fluoxetine exposure affects fetal development, resulting in cardiomyopathy and a higher

  13. Circadian rhythms in Macaca mulatta monkeys during Bion 11 flight

    NASA Technical Reports Server (NTRS)

    Alpatov, A. M.; Hoban-Higgins, T. M.; Klimovitsky, V. Y.; Tumurova, E. G.; Fuller, C. A.

    2000-01-01

    Circadian rhythms of primate brain temperature, head and ankle skin temperature, motor activity, and heart rate were studied during spaceflight and on the ground. In space, the circadian rhythms of all the parameters were synchronized with diurnal Zeitgebers. However, in space the brain temperature rhythm showed a significantly more delayed phase angle, which may be ascribed to an increase of the endogenous circadian period.

  14. Abnormalities in intracellular calcium regulation and contractile function in myocardium from dogs with pacing-induced heart failure.

    PubMed Central

    Perreault, C L; Shannon, R P; Komamura, K; Vatner, S F; Morgan, J P

    1992-01-01

    24 d of rapid ventricular pacing induced dilated cardiomyopathy with both systolic and diastolic dysfunction in conscious, chronically instrumented dogs. We studied mechanical properties and intracellular calcium (Ca2+i) transients of trabeculae carneae isolated from 15 control dogs (n = 32) and 11 dogs with pacing-induced cardiac failure (n = 26). Muscles were stretched to maximum length at 30 degrees C and stimulated at 0.33 Hz; a subset (n = 17 control, n = 17 myopathic) was loaded with the [Ca2+]i indicator aequorin. Peak tension was depressed in the myopathic muscles, even in the presence of maximally effective (i.e., 16 mM) [Ca2+] in the perfusate. However, peak [Ca2+]i was similar (0.80 +/- 0.13 vs. 0.71 +/- 0.05 microM; [Ca2+]o = 2.5 mM), suggesting that a decrease in Cai2+ availability was not responsible for the decreased contractility. The time for decline from the peak of the Cai2+ transient was prolonged in the myopathic group, which correlated with prolongation of isometric contraction and relaxation. However, similar end-diastolic [Ca2+]i was achieved in both groups (0.29 +/- 0.05 vs. 0.31 +/- 0.02 microM), indicating that Cai2+ homeostasis can be maintained in myopathic hearts. The inotropic response of the myopathic muscles to milrinone was depressed compared with the controls. However, when cAMP production was stimulated by pretreatment with forskolin, the response of the myopathic muscles to milrinone was improved. Our findings provide direct evidence that abnormal [Ca2+]i handling is an important cause of contractile dysfunction in dogs with pacing-induced heart failure and suggest that deficient production of cAMP may be an important cause of these changes in excitation-contraction coupling. PMID:1311723

  15. Abnormalities in intracellular calcium regulation and contractile function in myocardium from dogs with pacing-induced heart failure

    NASA Technical Reports Server (NTRS)

    Perreault, C. L.; Shannon, R. P.; Komamura, K.; Vatner, S. F.; Morgan, J. P.

    1992-01-01

    24 d of rapid ventricular pacing induced dilated cardiomyopathy with both systolic and diastolic dysfunction in conscious, chronically instrumented dogs. We studied mechanical properties and intracellular calcium (Ca2+i) transients of trabeculae carneae isolated from 15 control dogs (n = 32) and 11 dogs with pacing-induced cardiac failure (n = 26). Muscles were stretched to maximum length at 30 degrees C and stimulated at 0.33 Hz; a subset (n = 17 control, n = 17 myopathic) was loaded with the [Ca2+]i indicator aequorin. Peak tension was depressed in the myopathic muscles, even in the presence of maximally effective (i.e., 16 mM) [Ca2+] in the perfusate. However, peak [Ca2+]i was similar (0.80 +/- 0.13 vs. 0.71 +/- 0.05 microM; [Ca2+]o = 2.5 mM), suggesting that a decrease in Cai2+ availability was not responsible for the decreased contractility. The time for decline from the peak of the Cai2+ transient was prolonged in the myopathic group, which correlated with prolongation of isometric contraction and relaxation. However, similar end-diastolic [Ca2+]i was achieved in both groups (0.29 +/- 0.05 vs. 0.31 +/- 0.02 microM), indicating that Cai2+ homeostasis can be maintained in myopathic hearts. The inotropic response of the myopathic muscles to milrinone was depressed compared with the controls. However, when cAMP production was stimulated by pretreatment with forskolin, the response of the myopathic muscles to milrinone was improved. Our findings provide direct evidence that abnormal [Ca2+]i handling is an important cause of contractile dysfunction in dogs with pacing-induced heart failure and suggest that deficient production of cAMP may be an important cause of these changes in excitation-contraction coupling.

  16. Rhythm control in atrial fibrillation.

    PubMed

    Piccini, Jonathan P; Fauchier, Laurent

    2016-08-20

    Many patients with atrial fibrillation have substantial symptoms despite ventricular rate control and require restoration of sinus rhythm to improve their quality of life. Acute restoration (ie, cardioversion) and maintenance of sinus rhythm in patients with atrial fibrillation are referred to as rhythm control. The decision to pursue rhythm control is based on symptoms, the type of atrial fibrillation (paroxysmal, persistent, or long-standing persistent), patient comorbidities, general health status, and anticoagulation status. Many patients have recurrent atrial fibrillation and require further intervention to maintain long term sinus rhythm. Antiarrhythmic drug therapy is generally recommended as a first-line therapy and drug selection is on the basis of the presence or absence of structural heart disease or heart failure, electrocardiographical variables, renal function, and other comorbidities. In patients who continue to have recurrent atrial fibrillation despite medical therapy, catheter ablation has been shown to substantially reduce recurrent atrial fibrillation, decrease symptoms, and improve quality of life, although recurrence is common despite continued advancement in ablation techniques. PMID:27560278

  17. Cardiac Repolarization Abnormalities and Potential Evidence for Loss of Cardiac Sodium Currents on ECGs of Patients with Chagas' Heart Disease

    NASA Technical Reports Server (NTRS)

    Schlegel, T. T.; Medina, R.; Jugo, D.; Nunez, T. J.; Borrego, A.; Arellano, E.; Arenare, B.; DePalma, J. L.; Greco, E. C.; Starc, V.

    2007-01-01

    Some individuals with Chagas disease develop right precordial lead ST segment elevation in response to an ajmaline challenge test, and the prevalence of right bundle branch block (RBBB) is also high in Chagas disease. Because these same electrocardiographic abnormalities occur in the Brugada syndrome, which involves genetically defective cardiac sodium channels, acquired damage to cardiac sodium channels may also occur in Chagas disease. We studied several conventional and advanced resting 12-lead/derived Frank-lead ECG parameters in 34 patients with Chagas -related heart disease (mean age 39 14 years) and in 34 age-/gender-matched healthy controls. All ECG recordings were of 5-10 min duration, obtained in the supine position using high fidelity hardware/software (CardioSoft, Houston, TX). Even after excluding those Chagas patients who had resting BBBs, tachycardia and/or pathologic arrhythmia (n=8), significant differences remained in multiple conventional and advanced ECG parameters between the Chagas and control groups (n=26/group), especially in their respective QT interval variability indices, maximal spatial QRS-T angles and low frequency HRV powers (p=0.0006, p=0.0015 and p=0.0314 respectively). In relation to the issue of potential damage to cardiac sodium channels, the Chagas patients had: 1) greater than or equal to twice the incidence of resting ST segment elevation in leads V1-V3 (n=10/26 vs. n=5/26) and of both leftward (n=5/26 versus n=0/26) and rightward (n=7/26 versus n=3/26) QRS axis deviation than controls; 2) significantly increased filtered (40-250 Hz) QRS interval durations (92.1 8.5 versus 85.3 plus or minus 9.0 ms, p=0.022) versus controls; and 3) significantly decreased QT and especially JT interval durations versus controls (QT interval: 387.5 plus or minus 26.4 versus 408.9 plus or minus 34.6 ms, p=0.013; JT interval: 290.5 plus or minus 26.3 versus 314.8 plus or minus 31.3 ms; p=0.0029). Heart rates and Bazett-corrected QTc/JTc intervals

  18. Abnormal calcium homeostasis in heart failure with preserved ejection fraction is related to both reduced contractile function and incomplete relaxation: an electromechanically detailed biophysical modeling study

    PubMed Central

    Adeniran, Ismail; MacIver, David H.; Hancox, Jules C.; Zhang, Henggui

    2015-01-01

    Heart failure with preserved ejection fraction (HFpEF) accounts for about 50% of heart failure cases. It has features of incomplete relaxation and increased stiffness of the left ventricle. Studies from clinical electrophysiology and animal experiments have found that HFpEF is associated with impaired calcium homeostasis, ion channel remodeling and concentric left ventricle hypertrophy (LVH). However, it is still unclear how the abnormal calcium homeostasis, ion channel and structural remodeling affect the electro-mechanical dynamics of the ventricles. In this study we have developed multiscale models of the human left ventricle from single cells to the 3D organ, which take into consideration HFpEF-induced changes in calcium handling, ion channel remodeling and concentric LVH. Our simulation results suggest that at the cellular level, HFpEF reduces the systolic calcium level resulting in a reduced systolic contractile force, but elevates the diastolic calcium level resulting in an abnormal residual diastolic force. In our simulations, these abnormal electro-mechanical features of the ventricular cells became more pronounced with the increase of the heart rate. However, at the 3D organ level, the ejection fraction of the left ventricle was maintained due to the concentric LVH. The simulation results of this study mirror clinically observed features of HFpEF and provide new insights toward the understanding of the cellular bases of impaired cardiac electromechanical functions in heart failure. PMID:25852567

  19. Echocardiography for cardiac resynchronization therapy: recommendations for performance and reporting--a report from the American Society of Echocardiography Dyssynchrony Writing Group endorsed by the Heart Rhythm Society.

    PubMed

    Gorcsan, John; Abraham, Theodore; Agler, Deborah A; Bax, Jeroen J; Derumeaux, Genevieve; Grimm, Richard A; Martin, Randy; Steinberg, Jonathan S; Sutton, Martin St John; Yu, Cheuk-Man

    2008-03-01

    Echocardiography plays an evolving and important role in the care of heart failure patients treated with biventricular pacing, or cardiac resynchronization therapy (CRT). Numerous recent published reports have utilized echocardiographic techniques to potentially aide in patient selection for CRT prior to implantation and to optimized device settings afterwards. However, no ideal approach has yet been found. This consensus report evaluates the contemporary applications of echocardiography for CRT including relative strengths and technical limitations of several techniques and proposes guidelines regarding current and possible future clinical applications. Principal methods advised to qualify abnormalities in regional ventricular activation, known as dyssynchrony, include longitudinal velocities by color-coded tissue Doppler and the difference in left ventricular to right ventricular ejection using routine pulsed Doppler, or interventricular mechanical delay. Supplemental measures of radial dynamics which may be of additive value include septal-to-posterior wall delay using M-mode in patients with non-ischemic disease with technically high quality data, or using speckle tracking radial strain. A simplified post-CRT screening for atrioventricular optimization using Doppler mitral inflow velocities is also proposed. Since this is rapidly changing field with new information being added frequently, future modification and refinements in approach are anticipated to continue. PMID:18314047

  20. Noise-induced synchronous stochastic oscillations in small scale cultured heart-cell networks

    NASA Astrophysics Data System (ADS)

    Yuan, Lan; Liu, Zhi-Qiang; Zhang, Hui-Min; Ding, Xue-Li; Yang, Ming-Hao; Gu, Hua-Guang; Ren, Wei

    2011-02-01

    This paper reports that the synchronous integer multiple oscillations of heart-cell networks or clusters are observed in the biology experiment. The behaviour of the integer multiple rhythm is a transition between super- and subthreshold oscillations, the stochastic mechanism of the transition is identified. The similar synchronized oscillations are theoretically reproduced in the stochastic network composed of heterogeneous cells whose behaviours are chosen as excitable or oscillatory states near a Hopf bifurcation point. The parameter regions of coupling strength and noise density that the complex oscillatory rhythms can be simulated are identified. The results show that the rhythm results from a simple stochastic alternating process between super- and sub-threshold oscillations. Studies on single heart cells forming these clusters reveal excitable or oscillatory state nearby a Hopf bifurcation point underpinning the stochastic alternation. In discussion, the results are related to some abnormal heartbeat rhythms such as the sinus arrest.

  1. Heart failure overview

    MedlinePlus

    ... your heart contract at the same time. A defibrillator sends an electrical pulse to stop life-threatening ... heart rhythms. These people often receive an implanted defibrillator. When to Contact a Medical Professional Call your ...

  2. Cyanotic heart disease

    MedlinePlus

    ... or rhythms The treatment of choice for most congenital heart diseases is surgery to repair the defect . There are ... Some inherited factors may play a role in congenital heart disease. Many family members may be affected. If you ...

  3. [First in Russia experience of radiofrequency ablation with the help of robotic system of magnetic navigation on the occasion of heart rhythm disturbances].

    PubMed

    Ardashev, V N; Ardashev, A V; Zheliakov, E G; Shavarov, A A; Rybachenko, M S; Koshcheeva, L A

    2007-01-01

    We present first in Russia experience of interventional treatment of 15 patients (11 men, 4 women, mean age 34.2 +/- 13.9 years) in whom operations of endocardial electrophysiological study (endoEPS) and radiofrequency ablation (RFA) with the help of robotic system of magnetic navigation were carried out because of various disturbances of cardiac rhythm. WPW syndrome and atrioventricular reciprocal tachycardia were verified in 8 patients (in 2 women), ventricular disturbances of rhythm -- in 4 (2 women), atrioventricular nodal reciprocal tachycardia in 3. RFA was effective in all cases what was confirmed in the course of control protocol of endoEPS. Complications related to the conduction of the procedure were not noted. Average duration of the operation was 82 +/- 32 min, mean duration of RF application -- 3.2 +/- 1.1 min. Average duration of fluoroscopic exposure of a patient and physician was 22 +/- 4 min and 3 +/- 1 min, respectively. In 1 patient with WPW syndrome recurrence of anterograde conduction along right anterior-septal accessory atrioventricular pathway (AAP) emerged on the second day after operation. Repeat session with the use of manual technique of irrigation RFA lead to persistent elimination of conduction along AAP. In other cases no recurrences of cardiac rhythm disturbances were observed during 10.2 +/- 1.2 months of follow up in the absence of antiarrhythmic maintenance therapy. The use of robotic system of magnetic navigation for mapping and RFA is highly effective and safe method of treatment of patients with various disorders of cardiac rhythm allowing to lessen significantly radiation burden on the operating physician. PMID:18260929

  4. Metabolic circadian rhythms in embryonic turtles.

    PubMed

    Loudon, Fiona Kay; Spencer, Ricky-John; Strassmeyer, Alana; Harland, Karen

    2013-07-01

    Oviparous species are model organisms for investigating embryonic development of endogenous physiological circadian rhythms without the influence of maternal biorhythms. Recent studies have demonstrated that heart rates and metabolic rates of embryonic turtles are not constant or always maximal and can be altered in response to the presence of embryos at a more advanced stage of development within the nest. A first step in understanding the physiological mechanisms underpinning these responses in embryonic ectothermic organisms is to develop metabolic profiles (e.g., heart rate) at different temperatures throughout incubation. Heart beat and rhythmic patterns or changes in development may represent important signals or cues within a nest and may be vital to coordinate synchronous hatching well in advance of the final stages of incubation. We developed baseline embryonic heart-rate profiles of embryos of the short-necked Murray River turtle (Emydura macquarii) to determine the stage of embryogenesis that metabolic circadian rhythms become established, if at all. Eggs were incubated at constant temperatures (26°C and 30°C) and heart rates were monitored at 6-h intervals over 24 h every 7-11 days until hatching. Circadian heart rate rhythms were detected at the mid-gestation period and were maintained until hatching. Heart rates throughout the day varied by up to 20% over 24 h and were not related to time of day. This study demonstrated that endogenous metabolic circadian rhythms in developing embryos in turtle eggs establish earlier in embryogenesis than those documented in other vertebrate taxa during embryogenesis. Early establishment of circadian rhythms in heart rates may be critical for communication among embryos and synchrony in hatching and emergence from the nest. PMID:23652198

  5. Physiological basis for human autonomic rhythms

    NASA Technical Reports Server (NTRS)

    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

  6. Physiological basis for human autonomic rhythms.

    PubMed

    Eckberg, D L

    2000-07-01

    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

  7. Abnormal splicing in the N‐terminal variable region of cardiac troponin T impairs systolic function of the heart with preserved Frank‐Starling compensation

    PubMed Central

    Feng, Han‐Zhong; Chen, Guozhen; Nan, Changlong; Huang, Xupei; Jin, Jian‐Ping

    2014-01-01

    Abstract Abnormal splice‐out of the exon 7‐encoded segment in the N‐terminal variable region of cardiac troponin T (cTnT‐ΔE7) was found in turkeys and, together with the inclusion of embryonic exon (eTnT), in adult dogs with a correlation with dilated cardiomyopathy. Overexpression of these cTnT variants in transgenic mouse hearts significantly decreased cardiac function. To further investigate the functional effect of cTnT‐ΔE7 or ΔE7+eTnT in vivo under systemic regulation, echocardiography was carried out in single and double‐transgenic mice. No atrial enlargement, ventricular hypertrophy or dilation was detected in the hearts of 2‐month‐old cTnT‐ΔE7 and ΔE7+eTnT mice in comparison to wild‐type controls, indicating a compensated state. However, left ventricular fractional shortening and ejection fraction were decreased in ΔE7 and ΔE7+eTnT mice, and the response to isoproterenol was lower in ΔE7+eTnT mice. Left ventricular outflow tract velocity and gradient were decreased in the transgenic mouse hearts, indicating decreased systolic function. Ex vivo working heart function showed that high afterload or low preload resulted in more severe decreases in the systolic function and energetic efficiency of cTnT‐ΔE7 and ΔE7+eTnT hearts. On the other hand, increases in preload demonstrated preserved Frank‐Starling responses and minimized the loss of cardiac function and efficiency. The data demonstrate that the N‐terminal variable region of cardiac TnT regulates systolic function of the heart. PMID:25194024

  8. Heart CT scan

    MedlinePlus

    ... arteries to determine your risk for heart disease Congenital heart disease (heart problems that are present at birth) Problems ... Abnormal results may be due to: Aneurysm Congenital heart disease ... Narrowing of one or more coronary arteries (coronary artery ...

  9. Comparative proteomics reveals abnormal binding of ATGL and dysferlin on lipid droplets from pressure overload-induced dysfunctional rat hearts

    PubMed Central

    Li, Linghai; Zhang, Huina; Wang, Weiyi; Hong, Yun; Wang, Jifeng; Zhang, Shuyan; Xu, Shimeng; Shu, Qingbo; Li, Juanfen; Yang, Fuquan; Zheng, Min; Qian, Zongjie; Liu, Pingsheng

    2016-01-01

    Excessive retention of neutral lipids in cardiac lipid droplets (LDs) is a common observation in cardiomyopathy. Thus, the systematic investigation of the cardiac LD proteome will help to dissect the underlying mechanisms linking cardiac steatosis and myocardial dysfunction. Here, after isolation of LDs from normal and dysfunctional Sprague-Dawley rat hearts, we identified 752 heart-associated LD proteins using iTRAQ quantitative proteomic method, including 451 proteins previously unreported on LDs. The most noteworthy finding was the identification of the membrane resealing protein, dysferlin. An analysis of dysferlin truncation mutants indicated that its C2 domain was responsible for its LD localization. Quantitative proteomic results further determined that 27 proteins were increased and 16 proteins were decreased in LDs from post pressure overload-induced dysfunctional hearts, compared with normal hearts. Notably, adipose triacylglycerol lipase (ATGL) was dramatically decreased and dysferlin was substantially increased on dysfunctional cardiac LDs. This study for the first time reveals the dataset of the heart LD proteome in healthy tissue and the variation of it under cardiac dysfunction. These findings highlight an association between the altered LD protein localization of dysferlin and ATGL and myocardial dysfunction. PMID:26795240

  10. Comparative proteomics reveals abnormal binding of ATGL and dysferlin on lipid droplets from pressure overload-induced dysfunctional rat hearts.

    PubMed

    Li, Linghai; Zhang, Huina; Wang, Weiyi; Hong, Yun; Wang, Jifeng; Zhang, Shuyan; Xu, Shimeng; Shu, Qingbo; Li, Juanfen; Yang, Fuquan; Zheng, Min; Qian, Zongjie; Liu, Pingsheng

    2016-01-01

    Excessive retention of neutral lipids in cardiac lipid droplets (LDs) is a common observation in cardiomyopathy. Thus, the systematic investigation of the cardiac LD proteome will help to dissect the underlying mechanisms linking cardiac steatosis and myocardial dysfunction. Here, after isolation of LDs from normal and dysfunctional Sprague-Dawley rat hearts, we identified 752 heart-associated LD proteins using iTRAQ quantitative proteomic method, including 451 proteins previously unreported on LDs. The most noteworthy finding was the identification of the membrane resealing protein, dysferlin. An analysis of dysferlin truncation mutants indicated that its C2 domain was responsible for its LD localization. Quantitative proteomic results further determined that 27 proteins were increased and 16 proteins were decreased in LDs from post pressure overload-induced dysfunctional hearts, compared with normal hearts. Notably, adipose triacylglycerol lipase (ATGL) was dramatically decreased and dysferlin was substantially increased on dysfunctional cardiac LDs. This study for the first time reveals the dataset of the heart LD proteome in healthy tissue and the variation of it under cardiac dysfunction. These findings highlight an association between the altered LD protein localization of dysferlin and ATGL and myocardial dysfunction. PMID:26795240

  11. Increased Stiffness Is the Major Early Abnormality in a Pig Model of Severe Aortic Stenosis and Predisposes to Congestive Heart Failure in the Absence of Systolic Dysfunction

    PubMed Central

    Ishikawa, Kiyotake; Aguero, Jaume; Oh, Jae Gyun; Hammoudi, Nadjib; A Fish, Lauren; Leonardson, Lauren; Picatoste, Belén; Santos-Gallego, Carlos G; M. Fish, Kenneth; Hajjar, Roger J

    2015-01-01

    Background It remains unclear whether abnormal systolic function and relaxation are essential for developing heart failure in pathophysiology of severe aortic stenosis. Methods and Results Yorkshire pigs underwent surgical banding of the ascending aorta. The animals were followed for up to 5 months after surgery, and cardiac function was assessed comprehensively by invasive pressure–volume measurements, 3-dimensional echocardiography, echocardiographic speckle-tracking strain, and postmortem molecular and histological analyses. Pigs with aortic banding (n=6) exhibited significant left ventricular hypertrophy with increased stiffness compared with the control pigs (n=7) (end-diastolic pressure–volume relationship β: 0.053±0.017 versus 0.028±0.009 mm Hg/mL, P=0.007); however, all other parameters corresponding to systolic function, including ejection fraction, end-systolic pressure–volume relationship, preload recruitable stroke work, echocardiographic circumferential strain, and longitudinal strain, were not impaired in pigs with aortic banding. Relaxation parameters were also similar between groups. Sarcoplasmic reticulum calcium (Ca2+) ATPase protein levels in the left ventricle were similar. There were significant increases in 3-dimensional echocardiographic left atrial volumes, suggesting the usefulness of these indexes to detect increased stiffness. Right atrial pacing with a heart rate of 120 beats per minute induced increased end-diastolic pressure in pigs with aortic banding in contrast to decreased end-diastolic pressure in the control pigs. Histological evaluation revealed that increased stiffness was accompanied by cardiomyocyte hypertrophy and increased perimysial and perivascular fibrosis. Conclusion Increased stiffness is the major early pathological process that predisposes to congestive heart failure without abnormalities in systolic function and relaxation in a clinically relevant animal model of aortic stenosis. PMID:25994443

  12. Heart murmurs and other sounds

    MedlinePlus

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

  13. [Medicinal rhythm control in atrial fibrillation].

    PubMed

    Nowak, Bernd; Fürnkranz, Alexander

    2014-03-01

    Medicinal antiarrhythmic therapy is either used in the acute setting to convert atrial fibrillation to sinus rhythm or as chronic medication to preserve sinus rhythm if a rhythm control strategy is followed. The choice of the antiarrhythmic agent is based on the presence or absence of structural heart disease. In addition, oral anticoagulation should be established according to current guidelines. In the acute setting the armamentarium comprises flecainide, propafenone, vernakalant and amiodarone. Usually, combination therapy with an atrioventricular (AV) node slowing drug (a beta blocker or verapamil) is used. For chronic rhythm control a class IC drug, such as sotalol, dronedarone and amiodarone is given depending on the comorbidities. In the absence of structural heart disease, rare episodes of paroxysmal atrial fibrillation can be treated by a pill-in-the-pocket strategy, i.e. self-administered pharmacological cardioversion with flecainide or propafenone. Despite recent advances in catheter ablation of atrial fibrillation, medical rhythm control continues to play an important role due to its ubiquitous availability and relatively easy use. The risk for proarrhythmia has to be evaluated in all patients. PMID:24549989

  14. Correlation between echocardiographic endocardial surface mapping of abnormal wall motion and pathologic infarct size in autopsied hearts.

    PubMed

    Wilkins, G T; Southern, J F; Choong, C Y; Thomas, J D; Fallon, J T; Guyer, D E; Weyman, A E

    1988-05-01

    We previously developed a cross-sectional echocardiographic technique for quantitatively mapping the endocardial surface of the left ventricle and on which regions of abnormal wall motion can be superimposed in their correct spatial distribution. This endocardial mapping technique (EMT) provides a measure of the left ventricular endocardial surface area (ESA in cm2), the area of abnormal wall motion (AWM in cm2), and the overall percent dysfunction (%AWM) as a measure of the functional "infarct size." To test this approach, we compared the EMT measurements with the actual endocardial surface area (in cm2) and pathologic infarct size (both percent infarct by volume and percent endocardial surface overlying infarct) measured at later autopsy in 20 adults (14 men, six women) ranging in age from 47 to 76 years (mean 64 +/- 9.6 years). The median interval from echocardiographic study to death was 19 days (range 1 to 269 days). Patients were divided into two groups based on the age of their infarcts at the time of death: (1) recent (infarct age less than 14 days; mean age 5.3 +/- 4.6 days) and (2) old (infarct age greater than 6 months; mean age 3.6 +/- 3 years). When the left ventricular endocardial surface area at autopsy was compared with the EMT-derived ESA, a close correlation was found (EMT area = 1.17 X autopsy area + 20.4; r = .94, p = .0001), with the systematic difference in the measurements accounted for by systolic arrest, loss of distending pressure, and specimen shrinkage. The echocardiographic measure of infarct size (%AWM) correlated well with the autopsy percent infarction by volume (%AWM = 1.1 X infarct volume + 5.5; r = .82, p = .0001). Similarly, a good correlation was found for the percent abnormal wall motion and the autopsy percent endocardial surface area overlying infarction (%AWM = 0.89 X infarct area - 0.9; r = .89, p = .0001). When the data were examined in relation to the age of the myocardial infarct, the echocardiographic %AWM appeared to

  15. 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.

    PubMed

    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. PMID:22048796

  16. Circadian rhythm asynchrony in man during hypokinesis.

    NASA Technical Reports Server (NTRS)

    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.

  17. [Rhythms, depressions and light].

    PubMed

    Johnsson, Anders; Moan, Johan

    2006-04-01

    Many aspects of life in plants, animals and humans are controlled by light. Endogenous, so-called circadian rhythms in the body deviate from the exact 24-hour day and have typically a period of around 25.5 hours in man. Normally these rhythms adapt to the external 24-hour day-and night changes but under constant conditions the rhythms can free run. Many studies show how important the interplay between light and the circadian rhythms are for man as well as for other organisms. The control of these rhythms by light is mediated via the retina and the melatonin system in man. The adaptation of the rhythms is very important in shift work, in rapid jet lag travels over time zones, etc. Organisms often use the circadian rhythm to determine the length of day and of night, a feature that has given rise to the term biological clocks. A biological clock provides possibilities to determine the proper time for physiological processes to start in plants and animals (flowering, hibernation etc). The importance of light and circadian rhythms for seasonal affective disorders and manic-depressive disorders is also discussed. For several organisms one has now been able to specify genes that determine the period of the clocks. The rhythmic physiologic processes, the light reactions and the general importance of light for rhythms and for man are now studied at the molecular level. PMID:16619063

  18. Severe vitamin D deficiency in patients with Kawasaki disease: a potential role in the risk to develop heart vascular abnormalities?

    PubMed

    Stagi, Stefano; Rigante, Donato; Lepri, Gemma; Matucci Cerinic, Marco; Falcini, Fernanda

    2016-07-01

    Twenty-five-hydroxyvitamin D (25(OH)-vitamin D) is crucial in the regulation of immunologic processes, but-although its deficiency has been reported in patients with different rheumatological disorders-no data are available for Kawasaki disease (KD). The goals of this study were to assess the serum levels of 25(OH)-vitamin D in children with KD and evaluate the relationship with the eventual occurrence of KD-related vascular abnormalities. We evaluated serum 25(OH)-vitamin D levels in 79 children with KD (21 females, 58 males, median age 4.9 years, range 1.4-7.5 years) in comparison with healthy sex-/age-matched controls. A significantly higher percentage of KD patients (98.7 %) were shown to have reduced 25(OH)-vitamin D levels (<30 ng/mL) in comparison with controls (78.6 %, p < 0.0001). Furthermore, KD patients had severely low levels of 25(OH)-vitamin D than controls (9.17 ± 4.94 vs 23.3 ± 10.6 ng/mL, p < 0.0001), especially the subgroup who developed coronary artery abnormalities (4.92 ± 1.36 vs 9.41 ± 4.95 ng/mL, p < 0.0001). In addition, serum 25(OH)-vitamin D levels correlated not only with erythrosedimentation rate (p < 0.0001), C-reactive protein (p < 0.0001), hemoglobin level at KD diagnosis (p < 0.0001) but also with both coronary artery aneurysms (p = 0.005) and non-aneurysmatic cardiovascular lesions (p < 0.05). Low serum concentrations of 25(OH)-vitamin D might have a contributive role in the development of coronary artery complications observed in children with KD. PMID:25994612

  19. How are European patients at risk of malignant arrhythmias or sudden cardiac death identified and informed about their risk profile: results of the European Heart Rhythm Association survey.

    PubMed

    Proclemer, Alessandro; Bongiorni, Maria Grazia; Dagres, Nikolaos; Sciaraffia, Elena; Todd, Derick; Blomstrom-Lundqvist, Carina

    2015-06-01

    The purpose of this EP wire is to examine clinical practice in the field of screening of patients of risk of ventricular arrhythmias and/or sudden cardiac death (SCD) in European countries. A systematic screening programme existed in the majority of centres and was organized by a multidisciplinary dedicated team or by an activity programme of implantable cardioverter-defibrillator (ICD) or heart failure clinics. In particular, high-risk subgroups of patients with ischaemic and non-ischaemic cardiomyopathy ICD implantation are considered strongly indicated within 90 days of myocardial revascularization or initial diagnosis. Cardiac magnetic resonance imaging appears as an important tool to better characterize the left ventricular arrhythmogenic substrate in patients at risk of SCD. PMID:26023178

  20. Effect of short-term physical exercise on foetal heart rate and uterine activity in normal and abnormal pregnancies.

    PubMed

    Rauramo, I

    1987-01-01

    The response of a short-term submaximal bicycle ergometer test on foetal heart rate (FHR) and on uterine activity was studied in 61 pregnant women between pregnancy weeks 32 and 40. 28 of the women had uncomplicated pregnancies, 13 were hypertensive, 11 were diabetic, and 9 had intrahepatic cholestasis of pregnancy. After exercise, FHR declined in healthy subjects in pregnancy weeks past 35, whereas no significant change was found in such subjects before week 35 of pregnancy. Analysis of variance revealed a difference of FHR between subjects with umcomplicated and pre-eclamptic pregnancies in relation to time (p = 0.021). Exercise induced uterine contractions in hypertensive subjects. Foetal bradycardia was found in 2 healthy, in 2 pre-eclamptic, and in one cholestatic subject. In healthy pregnant women a non-reactive FHR with concomitant reduced FHR variability was found after exercise (P less than 0.01). The FHR variability of patients with pathologic pregnancies was less affected. These results suggest that, after a relatively strenuous short-term exercise, foetuses of mothers with uneventful pregnancies can be at risk of hypoxia in late pregnancy, but the clinical significance remains uncertain. PMID:3435001

  1. Heart and Down Syndrome

    MedlinePlus

    ... Associated Conditions » The Heart & Down Syndrome The Heart & Down Syndrome Abnormalities of the cardiovascular system are common in ... the Most Common Heart Defects in Children With Down Syndrome? The most common defects are Atrioventricular Septal Defect ( ...

  2. Cardiovascular and neurohumoral postural responses and baroreceptor abnormalities during a course of adjunctive vasodilator therapy with felodipine for congestive heart failure.

    PubMed

    Kassis, E; Amtorp, O

    1987-06-01

    Studies in patients with congestive heart failure (CHF) have demonstrated an abnormal beta-adrenergic reflex vasodilation during orthostatic tilt. Baroreflex modulation of vascular resistance in patients with CHF was investigated during therapy with a vasoselective calcium antagonist, felodipine. Eight patients on conventional therapy for severe CHF were studied after a 3 week course of additional felodipine or placebo treatment under randomized, double-blind, and crossover conditions. Forearm subcutaneous vascular resistance (FSVR) was estimated with use of the local 133Xe washout. Aortic pulsatile stretch, expressed as the systolic distension in percent of diastolic diameter, was calculated from echocardiographic measurements of aortic root diameters. At 3 weeks, felodipine reduced the arterial pressure, systemic vascular resistance, and FSVR, preserved cardiac filling pressures and heart rate, and increased cardiac output, stroke volume, and aortic pulsatile stretch. Upright tilt (45 degrees) was used to study baroreflex-mediated cardiovascular responses. The unloading of cardiopulmonary baroreceptors during upright tilt was substantial and about equal during both treatment courses, but the pulse pressure was maintained during the placebo and decreased during the felodipine period. During tilt, the patients on placebo failed to increase heart rate and their FSVR, systemic vascular resistance, and arterial mean pressure were decreased, whereas during tilt after felodipine, heart rate and systemic vascular resistance increased to maintain arterial mean pressure and FSVR also tended to increase. Both the stroke volume and aortic pulsatile stretch increased during tilt in patients on placebo but they decreased in those on felodipine. The tilt caused increments in circulating norepinephrine and epinephrine levels during both treatment regimens. Regulation of FSVR during the sympathetic stimulation of orthostatic stress was further elucidated. Proximal neural blockade

  3. Biological rhythms during residence in polar regions.

    PubMed

    Arendt, Josephine

    2012-05-01

    At Arctic and Antarctic latitudes, personnel are deprived of natural sunlight in winter and have continuous daylight in summer: light of sufficient intensity and suitable spectral composition is the main factor that maintains the 24-h period of human circadian rhythms. Thus, the status of the circadian system is of interest. Moreover, the relatively controlled artificial light conditions in winter are conducive to experimentation with different types of light treatment. The hormone melatonin and/or its metabolite 6-sulfatoxymelatonin (aMT6s) provide probably the best index of circadian (and seasonal) timing. A frequent observation has been a delay of the circadian system in winter. A skeleton photoperiod (2 × 1-h, bright white light, morning and evening) can restore summer timing. A single 1-h pulse of light in the morning may be sufficient. A few people desynchronize from the 24-h day (free-run) and show their intrinsic circadian period, usually >24 h. With regard to general health in polar regions, intermittent reports describe abnormalities in various physiological processes from the point of view of daily and seasonal rhythms, but positive health outcomes are also published. True winter depression (SAD) appears to be rare, although subsyndromal SAD is reported. Probably of most concern are the numerous reports of sleep problems. These have prompted investigations of the underlying mechanisms and treatment interventions. A delay of the circadian system with "normal" working hours implies sleep is attempted at a suboptimal phase. Decrements in sleep efficiency, latency, duration, and quality are also seen in winter. Increasing the intensity of ambient light exposure throughout the day advanced circadian phase and was associated with benefits for sleep: blue-enriched light was slightly more effective than standard white light. Effects on performance remain to be fully investigated. At 75°S, base personnel adapt the circadian system to night work within a week

  4. Understanding calendar rhythm.

    PubMed

    Reyes, D P

    1983-01-01

    Rhythm has been among the family planning methods endorsed since the start of the National Population Program in the Philippines, but it has not been given as much emphasis as the other methods such as oral contraception (OC), the IUD, and sterilization. For several years, no systematic effort was made to promote the effective use of rhythm. The 1978 Community Outreach Survey (COS) tried to determine the extent to which contraceptive methods were being used in the Outreach Project areas. The project covered 2,000 barangay service points (BSPs) with 1.76 million married couples of reproductive age (MCRA), representing 32% of the estimated total MCRA in the Philippines. The COS findings revealed that, of the total sexually active married women aged 15-49, 48% were using contraceptive methods. Of these, only 11.4% were using modern methods, 20% were using other program methods (rhythm, condom, and combination of rhythm and condom); and 16.7% were using nonprogram methods (withdrawal, abstinence, and others). When used in combination with other methods, rhythm had a monthly continuation rate of 96%; when used alone, 94%. The COS data showed that the rhythm method is practiced by a large number of Filipino couples. With the renewed interest in rhythm, it became imperative for the program to help rhythm acceptors use the method more effectively and thus reduce user failure. There continues to be need for data on the "product image" of rhythm. These include the emotions that come into play in the acceptance or rejection of rhythm, the perceived side effects as well as advantages of the method, the ways women communicate their "safe" and "unsafe" days to their husbands, the manner in which couples prevent sexual contact during "unsafe" days, and the attitude of couples toward abstinence. Among important study findings were the following: couples choose rhythm because it does not disturb the sexual act, has no side effects, and poses no religious objections; 1 of the

  5. The Study of Biobehavioral Rhythms in a Psychology Laboratory Course.

    ERIC Educational Resources Information Center

    Rowland, David L.; Wesselhoft, Theresa

    1998-01-01

    Reports on a laboratory experiment where students measured their heart rate, blood pressure, mood, alertness, and cognitive performance. Measures showed significant circadian heart rhythm variations. They were strongly correlated and peaked at different times. Discusses the implications of this and students' reactions to the experiment. (MJP)

  6. 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.

    PubMed

    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. PMID:25713012

  7. Circadian rhythms of visual accommodation responses and physiological correlations.

    NASA Technical Reports Server (NTRS)

    Murphy, M. R.; Randle, R. J.; Williams, B. A.

    1972-01-01

    Use of a recently developed servocontrolled infrared optometer to continuously record the state of monocular focus while subjects viewed a visual target for which the stimulus to focus was systematically varied. Calculated parameters form recorded data - e.g., speeds of accommodation to approaching and receding targets, magnitude of accommodation to step changes in target distance, and amplitude and phase lag of response to sinusoidally varying stimuli were submitted to periodicity analyses. Ear canal temperature (ECT) and heart rate (HR) rhythms were also recorded for physiological correlation with accommodation rhythms. HR demonstrated a 24-hr rhythm, but ECT data did not.

  8. Sleep and circadian rhythms

    NASA Technical Reports Server (NTRS)

    Monk, Timothy H.

    1991-01-01

    Three interacting processes are involved in the preservation of circadian rhythms: (1) endogenous rhythm generation mechanisms, (2) entrainment mechanisms to keep these rhythms 'on track', and (3) exogenous masking processes stemming from changes in environment and bahavior. These processes, particularly the latter two, can be dramatically affected in individuals of advanced age and in space travelers, with a consequent disruption in sleep and daytime functioning. This paper presents results of a phase-shift experiment investigating the age-related effects of the exogeneous component of circadian rhythms in various physiological and psychological functions by comparing these functions in middle aged and old subjects. Dramatic differences were found between the two age groups in measures of sleep, mood, activation, and performance efficiency.

  9. Race May Influence Risk for Irregular Heart Beat

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_158687.html Race May Influence Risk for Irregular Heart Beat Whites ... between the heart rhythm disorder atrial fibrillation and race, a new study says. Whites with heart failure ...

  10. Circadian rhythms of women with fibromyalgia

    NASA Technical Reports Server (NTRS)

    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.

  11. Distal 8p deletion (8) (p23.1): An easily missed chromosomal abnormality that may be associated with congenital heart defect and mental retardation

    SciTech Connect

    Wu, Bai-Lin; Schneider, G.H.; Sabatino, D.E.

    1996-03-01

    We describe the clinical manifestations and molecular cytogenetic analyses of three patients with a similar distal deletion of chromosome 8. Each child had mild developmental delay and subtle minor anomalies. Two had cardiac anomalies but no other major congenital anomalies were present. High resolution G and R banding showed in all three patients del(8)(p23.1), but the breakpoint in case 1 was distal to 8p23.1, in case 2 was in the middle of 8p23.1, and in case 3 proximal to 8p23.1. Fluorescence in situ hybridization (FISH) studies with a chromosome 8 paint probe confirmed that no other rearrangement had occurred. FISH with a chromosome 8-specific telomere probe indicated that two patients had terminal deletions. Chromosome analysis of the parents of case 1 and mother of case 2 were normal; the remaining parents were not available for study. Thirteen individual patients including the three in this study, and three relatives in one family with del(8)(p23.1), have been reported in the past 5 years. Major congenital anomalies, especially congenital heart defects, are most often associated with a breakpoint proximal to 8p23.1. Three patients were found within a 3-year period in this study and five cases were found within 4 years by another group, indicating that distal 8p deletion might be a relatively common chromosomal abnormality. This small deletion is easily overlooked (i.e., cases 1 and 2 were reported as normal at amniocentesis) and can be associated with few or no major congenital anomalies. 31 refs., 4 figs., 2 tabs.

  12. Local dynamics of heart rate: detection and prognostic implications.

    PubMed

    Moss, Travis J; Lake, Douglas E; Moorman, J Randall

    2014-10-01

    The original observation that reduced heart rate variability (HRV) confers poor prognosis after myocardial infarction has been followed by many studies of heart rate dynamics. We tested the hypothesis that an entropy-based local dynamics measure gave prognostic information in ambulatory patients undergoing 24-h electrocardiography. In this context, entropy is the probability that short templates will find matches in the time series. We studied RR interval time series from 24-h Holter monitors of 1564 consecutive patients over age 39. We generated histograms of the count of templates as a function of the number of templates matches in short RR interval time series, and found characteristic appearance of histograms for atrial fibrillation, sinus rhythm with normal HRV, and sinus rhythm with reduced HRV and premature ventricular contractions (PVCs). We developed statistical models to detect the abnormal dynamic phenotype of reduced HRV with PVCs and fashioned a local dynamics score (LDs) that, after controlling for age, added more prognostic information than other standard risk factors and common HRV metrics, including, to our surprise, the PVC count and the HRV of normal-to-normal intervals. Addition of the LDs to a predictive model using standard risk factors significantly increased the ROC area and the net reclassification improvement was 27%. We conclude that abnormal local dynamics of heart rate confer adverse prognosis in patients undergoing 24-h ambulatory electrocardiography. PMID:25229393

  13. GENERAL: Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

    NASA Astrophysics Data System (ADS)

    Zhang, Ning; Zhang, Hui-Min; Liu, Zhi-Qiang; Ding, Xue-Li; Yang, Ming-Hao; Gu, Hua-Guang; Ren, Wei

    2009-11-01

    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.

  14. Circadian rhythms in myocardial metabolism and contractile function; influence of workload and oleate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiple extra-cardiac stimuli, such as workload and circulating nutrients (e.g., fatty acids), known to influence myocardial metabolism and contractile function exhibit marked circadian rhythms. The aim of the present study was to investigate whether the rat heart exhibits circadian rhythms in its ...

  15. [Atrial fibrillation-pharmacological therapy for rate and rhythm control].

    PubMed

    Müller-Burri, Stephan Andreas

    2014-02-01

    The therapeutic management of patients with atrial fibrillation is based on the three pillars (1) prevention of thromboembolism, (2) rate control, and (3) rhythm control. Patients with one or more risk factors should be treated with an oral anticoagulants in order to prevent stroke and to reduce mortality. The goals of rate control, prevention of heart failure and alleviation of atrial fibrillation related symptoms, normally can be achieved by pharmacological agents slowing the conduction in the AV node (e. g. β-blockers, calcium channel blockers, digoxin). For patients remaining symptomatic despite sufficient rate control adding a rhythm control strategy may be considered. The currently available antiarrhythmic drugs (e. g. flecainide, propafenone, sotalol, dronedarone, amiodarone) are characterized by a rather low efficacy in maintaining sinus rhythm and various possibly life threatening side effects. Therefore, invasive therapies as catheter ablation are frequently needed to achieve rhythm control in symptomatic patients with atrial fibrillation. PMID:24463376

  16. Heart murmurs and other sounds

    MedlinePlus

    Chest sounds - murmurs; Heart sounds - abnormal; Murmur - innocent; Innocent murmur; Systolic heart murmur; Diastolic heart murmur ... classified ("graded") depending on how loud the murmur sounds with a stethoscope. The grading is on a ...

  17. Measuring Child Rhythm

    ERIC Educational Resources Information Center

    Payne, Elinor; Post, Brechtje; Astruc, Lluisa; Prieto, Pilar; Vanrell, Maria del Mar

    2012-01-01

    Interval-based rhythm metrics were applied to the speech of English, Catalan and Spanish 2, 4 and 6 year-olds, and compared with the (adult-directed) speech of their mothers. Results reveal that child speech does not fall into a well-defined rhythmic class: for all three languages, it is more "vocalic" (higher %V) than adult speech and has a…

  18. Biological Clocks & Circadian Rhythms

    ERIC Educational Resources Information Center

    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…

  19. Speech rhythm: a metaphor?

    PubMed Central

    Nolan, Francis; Jeon, Hae-Sung

    2014-01-01

    Is speech rhythmic? In the absence of evidence for a traditional view that languages strive to coordinate either syllables or stress-feet with regular time intervals, we consider the alternative that languages exhibit contrastive rhythm subsisting merely in the alternation of stronger and weaker elements. This is initially plausible, particularly for languages with a steep ‘prominence gradient’, i.e. a large disparity between stronger and weaker elements; but we point out that alternation is poorly achieved even by a ‘stress-timed’ language such as English, and, historically, languages have conspicuously failed to adopt simple phonological remedies that would ensure alternation. Languages seem more concerned to allow ‘syntagmatic contrast’ between successive units and to use durational effects to support linguistic functions than to facilitate rhythm. Furthermore, some languages (e.g. Tamil, Korean) lack the lexical prominence which would most straightforwardly underpin prominence of alternation. We conclude that speech is not incontestibly rhythmic, and may even be antirhythmic. However, its linguistic structure and patterning allow the metaphorical extension of rhythm in varying degrees and in different ways depending on the language, and it is this analogical process which allows speech to be matched to external rhythms. PMID:25385774

  20. Rhythm Sticks without Music.

    ERIC Educational Resources Information Center

    Mackin, Rosemary

    2000-01-01

    Provides 11 specific rhythm stick activities for preschoolers and kindergartners to increase children's awareness of basic music theory. Lessons incorporated in these activities include tempo, dynamics, intensity, laterality, and directionality. Lessons also address children's awareness of personal space and improved listening skills. Instructions…

  1. Speech rhythm: a metaphor?

    PubMed

    Nolan, Francis; Jeon, Hae-Sung

    2014-12-19

    Is speech rhythmic? In the absence of evidence for a traditional view that languages strive to coordinate either syllables or stress-feet with regular time intervals, we consider the alternative that languages exhibit contrastive rhythm subsisting merely in the alternation of stronger and weaker elements. This is initially plausible, particularly for languages with a steep 'prominence gradient', i.e. a large disparity between stronger and weaker elements; but we point out that alternation is poorly achieved even by a 'stress-timed' language such as English, and, historically, languages have conspicuously failed to adopt simple phonological remedies that would ensure alternation. Languages seem more concerned to allow 'syntagmatic contrast' between successive units and to use durational effects to support linguistic functions than to facilitate rhythm. Furthermore, some languages (e.g. Tamil, Korean) lack the lexical prominence which would most straightforwardly underpin prominence of alternation. We conclude that speech is not incontestibly rhythmic, and may even be antirhythmic. However, its linguistic structure and patterning allow the metaphorical extension of rhythm in varying degrees and in different ways depending on the language, and it is this analogical process which allows speech to be matched to external rhythms. PMID:25385774

  2. Tachycardia | Fast Heart Rate

    MedlinePlus

    ... Prevention & Treatment of High Blood Pressure High Blood Pressure Tools & Resources ... signals in the heart's upper chambers fire abnormally, which interferes with electrical signals coming from ...

  3. [PREVALENCE OF ATRIAL RHYTHM DISTURBANCES IN CARDIAC PATIENTS WITH COMORBIDITIES].

    PubMed

    Velichko, V L; Naychuk, O V; Lagoda, D O; Amirova, G U

    2015-01-01

    Atrial arrhythmias are the most common among all cardiac arrhythmias. The prevalence of atrial arrhythmias is increasing worldwide and has an impact on health indicators such as the loss of ability to work and mortality and increases the overall cardiovascular risk and/or heart disease occurence. This study indicates a high prevalence of atrial arthythmias in patients with ischemic heart disease and requires more detailed study in order to develop methods of preventing the onset of cardiac rhythm disorders. PMID:26118041

  4. Biological Rhythms During Residence in Polar Regions

    PubMed Central

    2012-01-01

    At Arctic and Antarctic latitudes, personnel are deprived of natural sunlight in winter and have continuous daylight in summer: light of sufficient intensity and suitable spectral composition is the main factor that maintains the 24-h period of human circadian rhythms. Thus, the status of the circadian system is of interest. Moreover, the relatively controlled artificial light conditions in winter are conducive to experimentation with different types of light treatment. The hormone melatonin and/or its metabolite 6-sulfatoxymelatonin (aMT6s) provide probably the best index of circadian (and seasonal) timing. A frequent observation has been a delay of the circadian system in winter. A skeleton photoperiod (2 × 1-h, bright white light, morning and evening) can restore summer timing. A single 1-h pulse of light in the morning may be sufficient. A few people desynchronize from the 24-h day (free-run) and show their intrinsic circadian period, usually >24 h. With regard to general health in polar regions, intermittent reports describe abnormalities in various physiological processes from the point of view of daily and seasonal rhythms, but positive health outcomes are also published. True winter depression (SAD) appears to be rare, although subsyndromal SAD is reported. Probably of most concern are the numerous reports of sleep problems. These have prompted investigations of the underlying mechanisms and treatment interventions. A delay of the circadian system with “normal” working hours implies sleep is attempted at a suboptimal phase. Decrements in sleep efficiency, latency, duration, and quality are also seen in winter. Increasing the intensity of ambient light exposure throughout the day advanced circadian phase and was associated with benefits for sleep: blue-enriched light was slightly more effective than standard white light. Effects on performance remain to be fully investigated. At 75°S, base personnel adapt the circadian system to night work within

  5. Circadian Rhythm Sleep Disorders

    PubMed Central

    Kim, Min Ju; Lee, Jung Hie; Duffy, Jeanne F.

    2014-01-01

    Objective To review circadian rhythm sleep disorders, including underlying causes, diagnostic considerations, and typical treatments. Methods Literature review and discussion of specific cases. Results Survey studies 1,2 suggest that up to 3% of the adult population suffers from a circadian rhythm sleep disorder (CRSD). However, these sleep disorders are often confused with insomnia, and an estimated 10% of adult and 16% of adolescent sleep disorders patients may have a CRSD 3-6. While some CRSD (such as jet lag) can be self-limiting, others when untreated can lead to adverse medical, psychological, and social consequences. The International Classification of Sleep Disorders classifies CRSD as dyssomnias, with six subtypes: Advanced Sleep Phase Type, Delayed Sleep Phase Type, Irregular Sleep Wake Type, Free Running Type, Jet Lag Type, and Shift Work Type. The primary clinical characteristic of all CRSD is an inability to fall asleep and wake at the desired time. It is believed that CRSD arise from a problem with the internal biological clock (circadian timing system) and/or misalignment between the circadian timing system and the external 24-hour environment. This misalignment can be the result of biological and/or behavioral factors. CRSD can be confused with other sleep or medical disorders. Conclusions Circadian rhythm sleep disorders are a distinct class of sleep disorders characterized by a mismatch between the desired timing of sleep and the ability to fall asleep and remain asleep. If untreated, CRSD can lead to insomnia and excessive daytime sleepiness, with negative medical, psychological, and social consequences. It is important for physicians to recognize potential circadian rhythm sleep disorders so that appropriate diagnosis, treatment, and referral can be made. PMID:25368503

  6. The primate seahorse rhythm.

    PubMed

    Campos, L M G; Cruz-Rizzolo, Roelf J; Pinato, L

    2015-07-10

    The main Zeitgeber, the day-night cycle, synchronizes the central oscillator which determines behaviors rhythms as sleep-wake behavior, body temperature, the regulation of hormone secretion, and the acquisition and processing of memory. Thus, actions such as acquisition, consolidation, and retrieval performed in the hippocampus are modulated by the circadian system and show a varied dependence on light and dark. To investigate changes in the hippocampus' cellular mechanism invoked by the day and night in a diurnal primate, this study analyzed the expression of PER2 and the calcium binding proteins (CaBPs) calbindin, calretinin and parvalbumin in the hippocampus of Sapajus apella, a diurnal primate, at two different time points, one during the day and one during the dark phase. The PER2 protein expression peaked at night in the antiphase described for the suprachiasmatic nucleus (SCN) of the same primate, indicating that hippocampal cells can present independent rhythmicity. This hippocampal rhythm was similar to that presented by diurnal but not nocturnal rodents. The CaBPs immunoreactivity also showed day/night variations in the cell number and in the cell morphology. Our findings provide evidence for the claim that the circadian regulation in the hippocampus may involve rhythms of PER2 and CaBPs expression that may contribute to the adaptation of this species in events and activities relevant to the respective periods. PMID:25862571

  7. Circadian Rhythms in Cyanobacteria.

    PubMed

    Cohen, Susan E; Golden, Susan S

    2015-12-01

    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

  8. Race May Influence Risk for Irregular Heart Beat

    MedlinePlus

    ... Whites with heart failure more likely to develop atrial fibrillation, research finds To use the sharing features on ... a strong link between the heart rhythm disorder atrial fibrillation and race, a new study says. Whites with ...

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

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

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

  10. Strange musical rhythms.

    PubMed

    Valentinuzzi, Max E; Hortt, Federico

    2014-01-01

    Music, along with its attached rhythm, has been with man for centuries, developing and evolving along with him. Its influence on human behavior and mood can reach levels whose limits are still unknown, especially in everything related to perception, where the whole nervous system is involved. Thus, physiology and psychology become strongly connected areas, while technology, through, for example, the production of music by electronic means, appears as a new unexpected ingredient that traditional composers and musicians of older times could not imagine. Obviously, bioengineering and its multiple branches are not absent either [1]?[4]. The literature is enormous with several specialized journals. When one looks back in time at the evolution of this complex area, the appearance of some kind of sudden jump (as a step function), which took place within a relatively recent short interval, is evident: music is now much more than what it used to be, and rhythm has made a step forward as if resurrecting and renewing the ancient Indian or African drums. PMID:25437475

  11. Sleep, Memory & Brain Rhythms

    PubMed Central

    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. PMID:26097242

  12. Meiotic abnormalities

    SciTech Connect

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  13. ACCF/AHA/ASE/ASNC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2013 multimodality appropriate use criteria for the detection and risk assessment of stable ischemic heart disease: a report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Failure Society of America, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

    PubMed

    Ronan, Grace; Wolk, Michael J; Bailey, Steven R; Doherty, John U; Douglas, Pamela S; Hendel, Robert C; Kramer, Christopher M; Min, James K; Patel, Manesh R; Rosenbaum, Lisa; Shaw, Leslee J; Stainback, Raymond F; Allen, Joseph M; Brindis, Ralph G; Kramer, Christopher M; Shaw, Leslee J; Cerqueira, Manuel D; Chen, Jersey; Dean, Larry S; Fazel, Reza; Hundley, W Gregory; Itchhaporia, Dipti; Kligfield, Paul; Lockwood, Richard; Marine, Joseph Edward; McCully, Robert Benjamin; Messer, Joseph V; O'Gara, Patrick T; Shemin, Richard J; Wann, L Samuel; Wong, John B; Patel, Manesh R; Kramer, Christopher M; Bailey, Steven R; Brown, Alan S; Doherty, John U; Douglas, Pamela S; Hendel, Robert C; Lindsay, Bruce D; Min, James K; Shaw, Leslee J; Stainback, Raymond F; Wann, L Samuel; Wolk, Michael J; Allen, Joseph M

    2014-02-01

    ). Testing for the evaluation of new or worsening symptoms following a prior test or procedure was found to be Appropriate. In addition, testing was found to be Appropriate or May Be Appropriate for patients within 90 days of an abnormal or uncertain prior result. Pre-operative testing was rated Appropriate or May Be Appropriate only for patients who had poor functional capacity and were undergoing vascular or intermediate risk surgery with 1 or more clinical risk factors or an organ transplant. The exercise ECG was suggested as an Appropriate test for cardiac rehabilitation clearance or for exercise prescription purposes. Testing in asymptomatic patients was generally found to be Rarely Appropriate, except for calcium scoring and exercise testing in intermediate and high-risk individuals and either stress or anatomic imaging in higher-risk individuals, which were all rated as May Be Appropriate. All modalities of follow-up testing after a prior test or percutaneous coronary intervention (PCI) within 2 years and within 5 years after coronary artery bypass graft (CABG) in the absence of new symptoms were rated Rarely Appropriate. Pre-operative testing for patients with good functional capacity, prior normal testing within 1 year, or prior to low-risk surgery also were found to be Rarely Appropriate. Imaging for an exercise prescription or prior to the initiation of cardiac rehabilitation was Rarely Appropriate except for cardiac rehabilitation clearance for heart failure patients. PMID:24374980

  14. ACCF/AHA/ASE/ASNC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2013 multimodality appropriate use criteria for the detection and risk assessment of stable ischemic heart disease: a report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Failure Society of America, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons.

    PubMed

    Wolk, Michael J; Bailey, Steven R; Doherty, John U; Douglas, Pamela S; Hendel, Robert C; Kramer, Christopher M; Min, James K; Patel, Manesh R; Rosenbaum, Lisa; Shaw, Leslee J; Stainback, Raymond F; Allen, Joseph M

    2014-02-01

    (ECG). Testing for the evaluation of new or worsening symptoms following a prior test or procedure was found to be Appropriate. In addition, testing was found to be Appropriate or May Be Appropriate for patients within 90 days of an abnormal or uncertain prior result. Pre-operative testing was rated Appropriate or May Be Appropriate only for patients who had poor functional capacity and were undergoing vascular or intermediate risk surgery with 1 or more clinical risk factors or an organ transplant. The exercise ECG was suggested as an Appropriate test for cardiac rehabilitation clearance or for exercise prescription purposes. Testing in asymptomatic patients was generally found to be Rarely Appropriate, except for calcium scoring and exercise testing in intermediate and high-risk individuals and either stress or anatomic imaging in higher-risk individuals, which were all rated as May Be Appropriate. All modalities of follow-up testing after a prior test or percutaneous coronary intervention (PCI) within 2 years and within 5 years after coronary artery bypass graft (CABG) in the absence of new symptoms were rated Rarely Appropriate. Pre-operative testing for patients with good functional capacity, prior normal testing within 1 year, or prior to low-risk surgery also were found to be Rarely Appropriate. Imaging for an exercise prescription or prior to the initiation of cardiac rehabilitation was Rarely Appropriate except for cardiac rehabilitation clearance for heart failure patients. PMID:24355759

  15. Selection and collection of multi parameter physiological data for cardiac rhythm diagnostic algorithm development

    NASA Astrophysics Data System (ADS)

    Bostock, J.; Weller, P.; Cooklin, M.

    2010-07-01

    Automated diagnostic algorithms are used in implantable cardioverter-defibrillators (ICD's) to detect abnormal heart rhythms. Algorithms misdiagnose and improved specificity is needed to prevent inappropriate therapy. Knowledge engineering (KE) and artificial intelligence (AI) could improve this. A pilot study of KE was performed with artificial neural network (ANN) as AI system. A case note review analysed arrhythmic events stored in patients ICD memory. 13.2% patients received inappropriate therapy. The best ICD algorithm had sensitivity 1.00, specificity 0.69 (p<0.001 different to gold standard). A subset of data was used to train and test an ANN. A feed-forward, back-propagation network with 7 inputs, a 4 node hidden layer and 1 output had sensitivity 1.00, specificity 0.71 (p<0.001). A prospective study was performed using KE to list arrhythmias, factors and indicators for which measurable parameters were evaluated and results reviewed by a domain expert. Waveforms from electrodes in the heart and thoracic bio-impedance; temperature and motion data were collected from 65 patients during cardiac electrophysiological studies. 5 incomplete datasets were due to technical failures. We concluded that KE successfully guided selection of parameters and ANN produced a usable system and that complex data collection carries greater risk of technical failure, leading to data loss.

  16. Breathing rhythms and emotions.

    PubMed

    Homma, Ikuo; Masaoka, Yuri

    2008-09-01

    Respiration is primarily regulated for metabolic and homeostatic purposes in the brainstem. However, breathing can also change in response to changes in emotions, such as sadness, happiness, anxiety or fear. Final respiratory output is influenced by a complex interaction between the brainstem and higher centres, including the limbic system and cortical structures. Respiration is important in maintaining physiological homeostasis and co-exists with emotions. In this review, we focus on the relationship between respiration and emotions by discussing previous animal and human studies, including studies of olfactory function in relation to respiration and the piriform-amygdala in relation to respiration. In particular, we discuss oscillations of piriform-amygdala complex activity and respiratory rhythm. PMID:18487316

  17. Degenerative lesions of a coronary chemoreceptor and nearby neural elements in the hearts of victims of sudden death.

    PubMed Central

    James, T. N.

    1986-01-01

    A coronary chemoreceptor and its neighboring nerves and ganglia were studied by serial sections of tissue taken from the hearts of sixteen victims of sudden unexpected death. Either focal or extensive inflammatory destruction was present in the chemoreceptors of 13 of the 16 hearts, and similar abnormalities of local nerves and ganglia were present in all 16 hearts. Since an identical coronary chemoreceptor in the dog has previously been shown to be the site of origin of a powerful reflex with major influence upon the electrical activity heart, the functional significance of the neural abnormalities found in these 16 human hearts may include important distortion of cardiac rhythm, conduction or repolarization. Future studies are needed to determine the prevalence of such lesions in the hearts of other victims of sudden death and among control subjects, as well as to determine the etiology of this special neuropathology of the heart. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:3837961

  18. A Prospective Exploratory Analysis of Cardiac Biomarkers and Electrocardiogram Abnormalities in Patients Receiving Thoracic Radiation Therapy with High-Dose Heart Exposure

    PubMed Central

    Gomez, Daniel R.; Yusuf, Syed Wamique; Munsell, Mark; Welsh, James W.; Liao, Zhongxing; Lin, Steven H.; Pan, Hubert; Chang, Joe Y.; Komaki, Ritsuko; Cox, James D.; McAleer, Mary Frances; Grosshans, David R.

    2014-01-01

    Introduction Acute effects of incidental cardiac irradiation in patients treated for thoracic cancer are not well characterized. We evaluated longitudinal changes in cardiac biomarkers for patients undergoing conformal radiation therapy (RT) with thoracic malignancies with high-dose cardiac exposure. Methods Twenty-five patients enrolled in a prospective trial (February 2009–December 2012) received ≥45 Gy to the thorax, with pretreatment estimates of ≥20 Gy to the heart. Chemotherapy was allowed except for doxorubicin or fluorouracil. Electrocardiographic (ECG), troponin-I (TnI), and brain natriuretic peptide (BNP) measurements were obtained before RT, within 24 hours of the first fraction, at the end of RT, and at first follow-up (1–2 months). These biomarkers were quantified at specific times and changes from baseline were evaluated with paired t tests. Results The median heart dose was 25.9 Gy (range 10.1–35.1 Gy). After the first RT fraction, no changes were noted in ECG or median Tnl or BNP levels; at the end of RT, two patients had elevated TnI and BNP, but neither difference was statistically significant. At first follow-up, TnI had returned to normal but the median BNP remained elevated (P=0.042). BNP did not increase over time in the 18 patients who received only RT. Twelve patients experienced acute ECG changes during RT, which resolved in seven patients by the next measurement. No patients experienced clinically significant RT-related events. Conclusion Increases in BNP and ECG changes were observed during high doses of radiation to the heart. The findings of this pilot study warrant further investigation and validation. PMID:25521400

  19. Congenital Abnormalities

    MedlinePlus

    ... serious health problems (e.g. Down syndrome ). Single-Gene Abnormalities Sometimes the chromosomes are normal in number, ... blood flow to the fetus impair fetal growth. Alcohol consumption and certain drugs during pregnancy significantly increase ...

  20. Craniofacial Abnormalities

    MedlinePlus

    ... of the skull and face. Craniofacial abnormalities are birth defects of the face or head. Some, like cleft ... palate, are among the most common of all birth defects. Others are very rare. Most of them affect ...

  1. Walking abnormalities

    MedlinePlus

    ... include: Arthritis of the leg or foot joints Conversion disorder (a psychological disorder) Foot problems (such as a ... injuries. For an abnormal gait that occurs with conversion disorder, counseling and support from family members are strongly ...

  2. Chromosome Abnormalities

    MedlinePlus

    ... decade, newer techniques have been developed that allow scientists and doctors to screen for chromosomal abnormalities without using a microscope. These newer methods compare the patient's DNA to a normal DNA ...

  3. Nail abnormalities

    MedlinePlus

    Nail abnormalities are problems with the color, shape, texture, or thickness of the fingernails or toenails. ... Fungus or yeast cause changes in the color, texture, and shape of the nails. Bacterial infection may ...

  4. Circadian Rhythms in Photosynthesis 1

    PubMed Central

    Hennessey, Timothy L.; Field, Christopher B.

    1991-01-01

    Net carbon assimilation and stomatal conductance to water vapor oscillated repeatedly in red kidney bean, Phaseolus vulgaris L., plants transferred from a natural photoperiod to constant light. In a gas exchange system with automatic regulation of selected environmental and physiological variables, assimilation and conductance oscillated with a free-running period of approximately 24.5 hours. The rhythms in carbon assimilation and stomatal conductance were closely coupled and persisted for more than a week under constant conditions. A rhythm in assimilation occurred when either ambient or intercellular CO2 partial pressure was held constant, demonstrating that the rhythm in assimilation was not entirely the result of stomatal effects on CO2 diffusion. Rhythms in assimilation and conductance were not expressed in plants grown under constant light at a constant temperature, demonstrating that the rhythms did not occur spontaneously but were induced by an external stimulus. In plants grown under constant light with a temperature cycle, a rhythm was entrained in stomatal conductance but not in carbon assimilation, indicating that the oscillators driving the rhythms differed in their sensitivity to environmental stimuli. PMID:16668261

  5. Rhythms of the hippocampal network.

    PubMed

    Colgin, Laura Lee

    2016-04-01

    The hippocampal local field potential (LFP) shows three major types of rhythms: theta, sharp wave-ripples and gamma. These rhythms are defined by their frequencies, they have behavioural correlates in several species including rats and humans, and they have been proposed to carry out distinct functions in hippocampal memory processing. However, recent findings have challenged traditional views on these behavioural functions. In this Review, I discuss our current understanding of the origins and the mnemonic functions of hippocampal theta, sharp wave-ripples and gamma rhythms on the basis of findings from rodent studies. In addition, I present an updated synthesis of their roles and interactions within the hippocampal network. PMID:26961163

  6. [Manifestations of polymorphism of β1-adrenoreceptors in patients with newly diagnosed cardiac rhythm disorders].

    PubMed

    Afanas'ev, S A; Rebrova, T Iu; Batalov, R E; Muslimova, É F; Borisova, E V; Popov, S V

    2013-01-01

    Individual peculiarities of the receptor apparatus of cardiomyocytes may determine pathological features of heart activity and susceptibility to pharmaceuticals. The possible role of beta-adrenoreceptor polymorphism in the development of cardiac rhythm disturbances is assessed by PCR. Special attention is given to A145G polymorphism of the ADRB1 gene in 127 patients with primary cardiac rhythm disorders. It was shown that AJ45G polymorphism (Ser49Gly) at DNA sites encoding for the amino acid sequence of beta-1 adrenoreceptors can influence the development of sex-specific cardiac rhythm disorders. PMID:24437165

  7. A de novo 0.63 Mb 6q25.1 deletion associated with growth failure, congenital heart defect, underdeveloped cerebellar vermis, abnormal cutaneous elasticity and joint laxity.

    PubMed

    Salpietro, Vincenzo; Ruggieri, Martino; Mankad, Kshitij; Di Rosa, Gabriella; Granata, Francesca; Loddo, Italia; Moschella, Emanuela; Calabro, Maria Pia; Capalbo, Anna; Bernardini, Laura; Novelli, Antonio; Polizzi, Agata; Seidler, Daniela G; Arrigo, Teresa; Briuglia, Silvana

    2015-09-01

    Deletions of the long arm of chromosome 6 are rare and are characterized by great clinical variability according to the deletion breakpoint. We report a on 6-year-old girl with a de novo 0.63 Mb deletion on chromosome 6q25.1 who demonstrated multiple congenital anomalies including a ventricular septal defect and an underdeveloped cerebellar vermis. She presented with severe pre- and post-natal growth failure, hyperextensible small joints (Beighton scores = 8/9; with normal parental scores), and an abnormally elastic, redundant skin. Abnormally high upper/lower segment ratio (i.e., 1.34 = > 3SD), mild dysmorphic facial features and developmental delay were also present. The girl's phenotype was compared with: (i) two girls, each previously reported by Bisgaard et al. and Caselli et al. with similar albeit larger (2.6-7.21 Mb) deletions; (ii) seven additional individuals (6 M; 1 F) harboring deletions within the 6q25.1 region reported in the literature; and (iii) ten further patients (5 M; 4 F; 1 unrecorded sex) recorded in the DECIPHER 6.0 database. We reported on the present girl as her findings could contribute to advance the phenotype of 6q deletions. In addition, the present deletion is the smallest so far recorded in the 6q25 region encompassing eight known genes [vs. 41 of Bisgaard et al., and 23 of Caselli et al.,], including the TAB2 (likely responsible for the girl's congenital heart defect), LATS1 gene, and the UST gene (a regulator of the homeostasis of proteoglycans, which could have played a role in the abnormal dermal and cartilage elasticity). PMID:25940952

  8. Biological rhythms and vector insects

    PubMed Central

    Marques, Mirian David

    2013-01-01

    The adjustment of all species, animals and plants, to the Earth’s cyclic environments is ensured by their temporal organisation. The relationships between parasites, vectors and hosts rely greatly upon the synchronisation of their biological rhythms, especially circadian rhythms. In this short note, parasitic infections by Protozoa and by microfilariae have been chosen as examples of the dependence of successful transmission mechanisms on temporal components. PMID:24473803

  9. Sleep, Circadian Rhythms, and Performance During Space Shuttle Missions

    NASA Technical Reports Server (NTRS)

    Neri, David F.; Czeisler, Charles A.; Dijk, Derk-Jan; Wyatt, James K.; Ronda, Joseph M.; Hughes, Rod J.

    2003-01-01

    Sleep and circadian rhythms may be disturbed during spaceflight, and these disturbances can affect crewmembers' performance during waking hours. The mechanisms underlying sleep and circadian rhythm disturbances in space are not well understood, and effective countermeasures are not yet available. We investigated sleep, circadian rhythms, cognitive performance, and light-dark cycles in five astronauts prior to, during, and after the 16-day STS-90 mission and the IO-day STS-95 mission. The efficacy of low-dose, alternative-night, oral melatonin administration as a countermeasure for sleep disturbances was evaluated. During these missions, scheduled rest activity cycles were 20-35 minutes shorter than 24 hours. Light levels on the middeck and in the Spacelab were very low; whereas on the flight deck (which has several windows), they were highly variable. Circadian rhythm abnormalities were observed. During the second half of the missions, the rhythm of urinary cortisol appeared to be delayed relative to the sleep-wake schedule. Performance during wakefulness was impaired. Astronauts slept only about 6.5 hours per day, and subjective sleep quality was lower in space. No beneficial effects of melatonin (0.3 mg administered prior to sleep episodes on alternate nights) were observed. A surprising finding was a marked increase in rapid eye movement (REM) sleep upon return to Earth. We conclude that these Space Shuttle missions were associated with circadian rhythm disturbances, sleep loss, decrements in neurobehavioral performance, and alterations in REM sleep homeostasis. Shorter than 24-hour rest-activity schedules and exposure to light-dark cycles inadequate for optimal circadian synchronization may have contributed to these disturbances.

  10. Ultrastructural correlates of left ventricular contraction abnormalities in patients with chronic ischemic heart disease: determinants of reversible segmental asynergy postrevascularization surgery.

    PubMed

    Flameng, W; Suy, R; Schwarz, F; Borgers, M; Piessens, J; Thone, F; Van Ermen, H; De Geest, H

    1981-11-01

    The relationships between structural alterations and left ventricular (LV) contraction abnormalities were studied in patients with coronary artery disease (CAD). Transmural biopsies of the LV anterior free wall were taken during aortocoronary bypass surgery (CABG) in 62 patients. When preoperative anterior wall motion (AWM) was reduced, significant myocardial cell degeneration was found in patients with as well as without previous anterior infarction (MI). The amount of myocardial fibrosis was increased only in patients with ECG evidence of previous anterior MI (p less than 0.001). In a second series of 139 CAD patients, cineventriculograms performed before and 8 months after CABG were examined. In patients with patent grafts to the LV anterior wall not previously infarcted, reduced AWM became normal. In patients with previous anterior MI the outcome of AWM was unpredictable (usually unimproved). Thus the histologic correlate of reduced AWM in segments not previously infarcted was progressive loss of contractile material in otherwise viable myocardial cells. Some reversibility was suggested by restoration of resting function after CABG. Unpredictable results in segments associated with pathologic Q waves appear related to the fibrous component of these previously infarcted areas. PMID:6975559

  11. An evaluation of the use of new Doppler methods for detecting longitudinal function abnormalities in a pacing-induced heart failure model

    NASA Technical Reports Server (NTRS)

    Tabata, Tomotsugu; Cardon, Lisa A.; Armstrong, Guy P.; Fukamach, Kiyotaka; Takagaki, Masami; Ochiai, Yoshie; McCarthy, Patrick M.; Thomas, James D.

    2003-01-01

    BACKGROUND: Doppler tissue echocardiography and color M-mode Doppler flow propagation velocity have proven useful in evaluating cross-sections of patients with left ventricular (LV) dysfunction, but experience with serial changes is limited. Purpose and methods: We tested their use by evaluating the temporal changes of LV function in a pacing-induced congestive heart failure model. Rapid ventricular pacing was initiated and maintained in 20 dogs for 4 weeks. Echocardiography was performed at baseline and weekly during brief pacing cessation. RESULTS: With rapid pacing, LV volume significantly increased and ejection fraction (57%-28%), stroke volume (37-18 mL), and mitral annulus systolic velocity (16.1-6.6 cm/s) by Doppler tissue echocardiography significantly decreased, with ejection fraction and mitral annulus systolic velocity closely correlated (r = 0.706, P <.0001). In contrast to the mitral inflow velocities, mitral annulus early diastolic velocity decreased steadily (12.3-7.3 cm/s) resulting in a dramatic decrease in mitral annulus early/late (1.22-0.57) diastolic velocity with no tendency toward pseudonormalization. The color M-mode Doppler flow propagation velocity also showed significant steady decrease (57-24 cm/s) throughout the pacing period. Multiple regression analysis chose mitral annulus systolic velocity (r = 0.895, P <.0001) and propagation velocity (r = 0.782, P <.0001) for the most important factor predicting LV systolic and diastolic function, respectively. CONCLUSIONS: Doppler tissue echocardiography and color M-mode Doppler flow could evaluate the serial deterioration in LV dysfunction throughout the pacing period. These were more useful in quantifying progressive LV dysfunction than conventional ehocardiographic techniques, and were probably relatively independent of preload. These techniques could be suitable for longitudinal evaluation in addition to the cross-sectional study.

  12. Albuminuria is Independently Associated with Cardiac Remodeling, Abnormal Right and Left Ventricular Function, and Worse Outcomes in Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Katz, Daniel H.; Burns, Jacob A.; Aguilar, Frank G.; Beussink, Lauren; Shah, Sanjiv J.

    2014-01-01

    Objectives To determine the relationship between albuminuria and cardiac structure/function in heart failure with preserved ejection fraction (HFpEF). Background Albuminuria, a marker of endothelial dysfunction, has been associated with adverse cardiovascular outcomes in HFpEF. However, the relationship between albuminuria and cardiac structure/function in HFpEF has not been well studied. Methods We measured urinary albumin-to-creatinine ratio (UACR) and performed comprehensive echocardiography, including tissue Doppler imaging and right ventricular (RV) evaluation, in a prospective study of 144 patients with HFpEF. Multivariable-adjusted linear regression was used to determine the association between UACR and echocardiographic parameters. Cox proportional hazards analyses were used to determine the association between UACR and outcomes. Results The mean age was 66±11 years, 62% were female, and 42% were African-American. Higher UACR was associated with greater left ventricular (LV) mass, lower preload-recruitable stroke work, and lower global longitudinal strain. Higher UACR was also significantly associated with RV remodeling (for each doubling of UACR, RV wall thickness was 0.9 mm higher [95% confidence interval (CI) 0.05–0.14 mm; P=0.001, adjusted P=0.01]) and worse RV systolic function (for each doubling of UACR, RV fractional area change was 0.56% lower [95% CI 0.14–0.98%; P=0.01, adjusted P=0.03]. The association between UACR and RV parameters persisted after excluding patients with macroalbuminuria (UACR > 300 mg/g). Increased UACR was also independently associated with worse outcomes. Conclusions In HFpEF, increased UACR is a prognostic marker and is associated with increased RV and LV remodeling, and longitudinal systolic dysfunction. PMID:25282032

  13. Late prognostic value of scintigraphic parameters of acute myocardial infarction size in complicated myocardial infarction without heart failure

    SciTech Connect

    Botvinick, E.H.; Perez-Gonzalez, J.F.; Dunn, R.; Ports, T.; Chatterjee, K.; Parmley, W.

    1983-04-01

    Perfusion scintigraphy with thallium-201, infarct scintigraphy with technetium-99m pyrophosphate (TcPYP), and equilibrium blood pool scintigraphy were performed during the initial hospitalization for acute myocardial infarction (MI) in 25 patients without evidence of heart failure who presented with advanced electrocardiographic rhythm and conduction disturbances requiring treatment. Scintigraphic findings during short-term hospitalization were related to the late clinical follow-up performed an average of 14 months later, where patients were grouped as asymptomatic, 8 patients; symptomatic, 9 patients; and deceased, 8 patients. Quantitation of perfusion abnormalities, TcPYP image abnormalities, and left ventricular ejection fraction (EF) revealed that the deceased group had significantly larger TcPYP abnormalities (36 +/- 20 cm2), absolute perfusion abnormalities (32 +/- 16 cm2), and perfusion abnormalities expressed as a percentage of the projected left ventricular area (42 +/- 8%) than the asymptomatic group (13 +/- 8 cm2, 14 +/- 6 cm2, and 20 +/- 9%; p less than 0.05, p greater than 0.05, and p less than 0.01, respectively). The percent perfusion abnormality was significantly larger in the deceased group (42 +/- 8%, p less than 0.01) than in either the symptomatic group (35 +/- 13%, p less than 0.01) or the asymptomatic group (20 +/- 9%), and this parameter in the symptomatic group also differed from that in the asymptomatic group (p less than 0.01). The study indicates that patients with rhythm and conduction disturbances and without congestive heart failure during acute MI may follow an uncomplicated or a complicated late clinical course. Early scintigraphic measurements of MI and perfusion correlate well with this outcome; however, EF could not differentiate among prognostic subgroups.

  14. Endogenous rhythms influence interpersonal synchrony.

    PubMed

    Zamm, Anna; Wellman, Chelsea; Palmer, Caroline

    2016-05-01

    Interpersonal synchrony, the temporal coordination of actions between individuals, is fundamental to social behaviors from conversational speech to dance and music-making. Animal models indicate constraints on synchrony that arise from endogenous rhythms: Intrinsic periodic behaviors or processes that continue in the absence of change in external stimulus conditions. We report evidence for a direct causal link between endogenous rhythms and interpersonal synchrony in a music performance task, which places high demands on temporal coordination. We first establish that endogenous rhythms, measured by spontaneous rates of individual performance, are stable within individuals across stimulus materials, limb movements, and time points. We then test a causal link between endogenous rhythms and interpersonal synchrony by pairing each musician with a partner who is either matched or mismatched in spontaneous rate and by measuring their joint behavior up to 1 year later. Partners performed melodies together, using either the same or different hands. Partners who were matched for spontaneous rate showed greater interpersonal synchrony in joint performance than mismatched partners, regardless of hand used. Endogenous rhythms offer potential to predict optimal group membership in joint behaviors that require temporal coordination. (PsycINFO Database Record PMID:26820249

  15. Biological rhythms and mood disorders

    PubMed Central

    Salvatore, Paola; Indic, Premananda; Murray, Greg; Baldessarini, Ross J.

    2012-01-01

    Integration of several approaches concerning time and temporality can enhance the pathophysiological study of major mood disorders of unknown etiology. We propose that these conditions might be interpreted as disturbances of temporal profile of biological rhythms, as well as alterations of time-consciousness. Useful approaches to study time and temporality include philological suggestions, phenomenological and psychopathological conceptualizatíons, clinical descriptions, and research on circadian and ultradían rhythms, as well as nonlinear dynamics approaches to their analysis. PMID:23393414

  16. Control mechanisms in physiological rhythms

    NASA Technical Reports Server (NTRS)

    Mizell, S.

    1973-01-01

    A search was made for the factors involved in regulating rhythmic body functions. The basic premise was that at a particular point in time, any cell can normally act in one of two ways. It can either be engaged in dividing or carrying out its particular function. Experimental results indicate rhythmic functions are controlled by a lighting regime and that an inverse correlation exists between rhythms of cell division and cell function. Data also show rhythms are a function of animal sex and environment.

  17. Clinical and epidemiological study of chronic heart involvment in Chagas' disease*

    PubMed Central

    Puigbó, J. J.; Rhode, J. R. Nava; Barrios, H. García; Suárez, J. A.; Yépez, C. Gil

    1966-01-01

    It has been estimated that, in vast areas of the American continent, there is a high prevalence of human infection by Trypanosoma cruzi. Such infection can lead to a variety of heart diseases, predominantly with involvement of the myocardium. The aim of the present work was to determine the prevalence of heart disease in two rural areas of Venezuela with a high endemicity of Chagas' disease and to try to determine the natural history of the disease. It is shown that a form of chronic myocardial disease in patients with positive specific serology and good functional capacity is highly prevalent. Electrocardiographic patterns typical of the initial and developing stages of the disease, as well as early abnormalities of the cardiac rhythm, are described and illustrated. The present work forms part of a longitudinal study still in progress. ImagesFIG. 2FIG. 8FIG. 9FIG. 6FIG. 7FIG. 3FIG. 5FIG. 4 PMID:4957485

  18. Ictal Cardiac Ryhthym Abnormalities

    PubMed Central

    Ali, Rushna

    2016-01-01

    Cardiac rhythm abnormalities in the context of epilepsy are a well-known phenomenon. However, they are under-recognized and often missed. The pathophysiology of these events is unclear. Bradycardia and asystole are preceded by seizure onset suggesting ictal propagation into the cortex impacting cardiac autonomic function, and the insula and amygdala being possible culprits. Sudden unexpected death in epilepsy (SUDEP) refers to the unanticipated death of a patient with epilepsy not related to status epilepticus, trauma, drowning, or suicide. Frequent refractory generalized tonic-clonic seizures, anti-epileptic polytherapy, and prolonged duration of epilepsy are some of the commonly identified risk factors for SUDEP. However, the most consistent risk factor out of these is an increased frequency of generalized tonic–clonic seizures (GTC). Prevention of SUDEP is extremely important in patients with chronic, generalized epilepsy. Since increased frequency of GTCS is the most consistently reported risk factor for SUDEP, effective seizure control is the most important preventive strategy. PMID:27347227

  19. Circadian rhythms, Wnt/beta-catenin pathway and PPAR alpha/gamma profiles in diseases with primary or secondary cardiac dysfunction

    PubMed Central

    Lecarpentier, Yves; Claes, Victor; Duthoit, Guillaume; Hébert, Jean-Louis

    2014-01-01

    Circadian clock mechanisms are far-from-equilibrium dissipative structures. Peroxisome proliferator-activated receptors (PPAR alpha, beta/delta, and gamma) play a key role in metabolic regulatory processes, particularly in heart muscle. Links between circadian rhythms (CRs) and PPARs have been established. Mammalian CRs involve at least two critical transcription factors, CLOCK and BMAL1 (Gekakis et al., 1998; Hogenesch et al., 1998). PPAR gamma plays a major role in both glucose and lipid metabolisms and presents circadian properties which coordinate the interplay between metabolism and CRs. PPAR gamma is a major component of the vascular clock. Vascular PPAR gamma is a peripheral regulator of cardiovascular rhythms controlling circadian variations in blood pressure and heart rate through BMAL1. We focused our review on diseases with abnormalities of CRs and with primary or secondary cardiac dysfunction. Moreover, these diseases presented changes in the Wnt/beta-catenin pathway and PPARs, according to two opposed profiles. Profile 1 was defined as follows: inactivation of the Wnt/beta-catenin pathway with increased expression of PPAR gamma. Profile 2 was defined as follows: activation of the Wnt/beta-catenin pathway with decreased expression of PPAR gamma. A typical profile 1 disease is arrhythmogenic right ventricular cardiomyopathy, a genetic cardiac disease which presents mutations of the desmosomal proteins and is mainly characterized by fatty acid accumulation in adult cardiomyocytes mainly in the right ventricle. The link between PPAR gamma dysfunction and desmosomal genetic mutations occurs via inactivation of the Wnt/beta-catenin pathway presenting oscillatory properties. A typical profile 2 disease is type 2 diabetes, with activation of the Wnt/beta-catenin pathway and decreased expression of PPAR gamma. CRs abnormalities are present in numerous pathologies such as cardiovascular diseases, sympathetic/parasympathetic dysfunction, hypertension, diabetes

  20. Heart Health

    MedlinePlus

    ... Connected Home » Heart Health Heath and Aging Heart Health Your Heart Changes to Your Heart With ... are both taking steps toward heart health. Your Heart Your heart is a strong muscle about the ...

  1. QT interval variability in body surface ECG: measurement, physiological basis, and clinical value: position statement and consensus guidance endorsed by the European Heart Rhythm Association jointly with the ESC Working Group on Cardiac Cellular Electrophysiology.

    PubMed

    Baumert, Mathias; Porta, Alberto; Vos, Marc A; Malik, Marek; Couderc, Jean-Philippe; Laguna, Pablo; Piccirillo, Gianfranco; Smith, Godfrey L; Tereshchenko, Larisa G; Volders, Paul G A

    2016-06-01

    This consensus guideline discusses the electrocardiographic phenomenon of beat-to-beat QT interval variability (QTV) on surface electrocardiograms. The text covers measurement principles, physiological basis, and clinical value of QTV. Technical considerations include QT interval measurement and the relation between QTV and heart rate variability. Research frontiers of QTV include understanding of QTV physiology, systematic evaluation of the link between QTV and direct measures of neural activity, modelling of the QTV dependence on the variability of other physiological variables, distinction between QTV and general T wave shape variability, and assessing of the QTV utility for guiding therapy. Increased QTV appears to be a risk marker of arrhythmic and cardiovascular death. It remains to be established whether it can guide therapy alone or in combination with other risk factors. QT interval variability has a possible role in non-invasive assessment of tonic sympathetic activity. PMID:26823389

  2. Circadian rhythms and the suprachiasmatic nucleus in perinatal development, aging and Alzheimer's disease.

    PubMed

    Mirmiran, M; Swaab, D F; Kok, J H; Hofman, M A; Witting, W; Van Gool, W A

    1992-01-01

    Circadian rhythms are already present in the fetus. At a certain stage of pre-natal hypothalamic development (around 30 weeks of gestation) the fetus becomes responsive to maternal circadian signals. Moreover, recent studies showed that the fetal biological clock is able to generate circadian rhythms, as exemplified by the rhythms of body temperature and heart rate of pre-term babies in the absence of maternal or environmental entrainment factors. Pre-term babies that are deprived of maternal entrainment and kept under constant environmental conditions (e.g., continuous light) in the neonatal intensive care unit run the risk of developing a biological clock dysfunctioning. However, the fact should be acknowledged that at least in mice the development of the circadian pacemaker (i.e., SCN) does not depend on environmental influences (Davis and Menaker, 1981), although other data suggest that severe disruption of the maternal circadian rhythm indeed abolishes the circadian rhythm of the fetal SCN (Shibata and Moore, 1988). During aging and in particular in AD circadian rhythms are disturbed. These disturbances include phase advance and reduced period and amplitude, as well as an increased intradaily variability and a decreased interdaily stability of the rhythm. Among the factors underlying these changes the loss of SCN neurons seems to play a central role. Other contributory factors may be reduced amount of light, degenerative changes in the visual system and the level of activity and decreased melatonin. PMID:1480747

  3. Hearts and flowers: Bryophyllum poisoning of cattle.

    PubMed

    McKenzie, R A; Dunster, P J

    1986-07-01

    Findings from natural cases and experiments with cattle emphasise that flowering plants are the most important form of Bryophyllum (Kalanchoe) spp in poisonings in Australia. The main life-threatening lesion is myocardial. The effects on the alimentary tract are less important than was believed previously. B. tubiflorum, B. daigremontianum x B. tubiflorum, B. pinnatum and B. proliferum caused 41 recorded poisoning incidents affecting 379 cattle in Queensland between 1960 and 1984. Poisoning occurred between May and October--the flowering season of these plants. Experimental B. tubiflorum poisoning and natural poisonings produced anorexia, depression, ruminal atony, diarrhoea, heart rate and rhythm abnormalities, dyspnoea and death. Increased plasma concentrations of urea, creatinine and glucose and decreased chloride were measured experimentally. Both natural and experimental cases had myocardial degeneration and necrosis with haemorrhages of the heart and alimentary tract. Cattle with severe dyspnoea had atelectasis and emphysema of the lungs. Some cattle had mild nephrosis. The median lethal doses of B. tubiflorum flowers, roots and leaf plus stem were 0.7, 2.3 and 5.0 g dry matter/kg liveweight respectively (7, 7 and 40 g wet weight/kg). Bufadienolides have been isolated recently from B. tubiflorum flowers and the syndrome is consistent with cardiac glycoside poisoning. PMID:3778371

  4. Circadian rhythms, alcohol and gut interactions

    PubMed Central

    Forsyth, Christopher B.; Voigt, Rbin M.; Burgess, Helen J.; Swanson, Garth R.; Keshavarzian, Ali

    2015-01-01

    The circadian clock establishes rhythms throughout the body with an approximately 24 hour period that affect expression of hundreds of genes. Epidemiological data reveal chronic circadian misalignment, common in our society, significantly increases the risk for a myriad of diseases, including cardiovascular disease, diabetes, cancer, infertility and gastrointestinal disease. Disruption of intestinal barrier function, also known as gut leakiness, is especially important in alcoholic liver disease (ALD). Several studies have shown that alcohol causes ALD in only a 20–30% subset of alcoholics. Thus, a better understanding is needed of why only a subset of alcoholics develops ALD. Compelling evidence shows that increased gut leakiness to microbial products and especially LPS play a critical role in the pathogenesis of ALD. Clock and other circadian clock genes have been shown to regulate lipid transport, motility and other gut functions. We hypothesized that one possible mechanism for alcohol-induced intestinal hyper-permeability is through disruption of central or peripheral (intestinal) circadian regulation. In support of this hypothesis, our recent data shows that disruption of circadian rhythms makes the gut more susceptible to injury. Our in vitro data show that alcohol stimulates increased Clock and Per2 circadian clock proteins and that siRNA knockdown of these proteins prevents alcohol-induced permeability. We also show that intestinal Cyp2e1-mediated oxidative stress is required for alcohol-induced upregulation of Clock and Per2 and intestinal hyperpermeability. Our mouse model of chronic alcohol feeding shows that circadian disruption through genetics (in ClockΔ19 mice) or environmental disruption by weekly 12h phase shifting results in gut leakiness alone and exacerbates alcohol-induced gut leakiness and liver pathology. Our data in human alcoholics show they exhibit abnormal melatonin profiles characteristic of circadian disruption. Taken together our

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

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

    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.

  6. The International Sweethearts of Rhythm.

    ERIC Educational Resources Information Center

    Sher, Liz

    1987-01-01

    The International Sweethearts of Rhythm, a popular, long-lived, all-female jazz band of the 1940s, were the first racially integrated women's band in America. Their achievement has been largely neglected by music historians. A brief history of the band is presented, and their significance is discussed. (BJV)

  7. Biochemical Oscillations and Cellular Rhythms

    NASA Astrophysics Data System (ADS)

    Goldbeter, Albert; Berridge, Foreword by M. J.

    1997-04-01

    1. Introduction; Part I. Glycolytic Oscillations: 2. Oscillatory enzymes: simple periodic behaviour in an allosteric model for glycolytic oscillations; Part II. From Simple to Complex Oscillatory Behaviour; 3. Birhythmicity: coexistence between two stable rhythms; 4. From simple periodic behaviour to complex oscillations, including bursting and chaos; Part III. Oscillations Of Cyclic Amo In Dictyostelium Cells: 5. Models for the periodic synthesis and relay of camp signals in Dictyostelium discoideum amoebae; 6. Complex oscillations and chaos in the camp signalling system of Dictyostelium; 7. The onset of camp oscillations in Dictyostelium as a model for the ontogenesis of biological rhythms; Part IV. Pulsatile Signalling In Intercellular Communication: 8. Function of the rhythm of intercellular communication in Dictyostelium. Link with pulsatile hormone secretion; Part V. Calcium Oscillations: 9. Oscillations and waves of intracellular calcium; Part VI. The Mitotic Oscillator: 10. Modelling the mitotic oscillator driving the cell division cycle; Part VII. Circadian Rhythms: 11. Towards a model for circadian oscillations in the Drosophila period protein (PER); 12. Conclusions and perspectives; References.

  8. Rhythm Deficits in "Tone Deafness"

    ERIC Educational Resources Information Center

    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…

  9. Circadian rhythms, the molecular clock, and skeletal muscle.

    PubMed

    Harfmann, Brianna D; Schroder, Elizabeth A; Esser, Karyn A

    2015-04-01

    Circadian rhythms are the approximate 24-h biological cycles that function to prepare an organism for daily environmental changes. They are driven by the molecular clock, a transcriptional:translational feedback mechanism that in mammals involves the core clock genes Bmal1, Clock, Per1/2, and Cry1/2. The molecular clock is present in virtually all cells of an organism. The central clock in the suprachiasmatic nucleus (SCN) has been well studied, but the clocks in the peripheral tissues, such as heart and skeletal muscle, have just begun to be investigated. Skeletal muscle is one of the largest organs in the body, comprising approximately 45% of total body mass. More than 2300 genes in skeletal muscle are expressed in a circadian pattern, and these genes participate in a wide range of functions, including myogenesis, transcription, and metabolism. The circadian rhythms of skeletal muscle can be entrained both indirectly through light input to the SCN and directly through time of feeding and activity. It is critical for the skeletal muscle molecular clock not only to be entrained to the environment but also to be in synchrony with rhythms of other tissues. When circadian rhythms are disrupted, the observed effects on skeletal muscle include fiber-type shifts, altered sarcomeric structure, reduced mitochondrial respiration, and impaired muscle function. Furthermore, there are detrimental effects on metabolic health, including impaired glucose tolerance and insulin sensitivity, which skeletal muscle likely contributes to considering it is a key metabolic tissue. These data indicate a critical role for skeletal muscle circadian rhythms for both muscle and systems health. Future research is needed to determine the mechanisms of molecular clock function in skeletal muscle, identify the means by which skeletal muscle entrainment occurs, and provide a stringent comparison of circadian gene expression across the diverse tissue system of skeletal muscle. PMID:25512305

  10. Concepts in human biological rhythms

    PubMed Central

    Reinberg, Alain; Ashkenazi, Israel

    2003-01-01

    Biological rhythms and their temporal organization are adaptive phenomena to periodic changes in environmental factors linked to the earth's rotation on its axis and around the sun. Experimental data from the plant and animal kingdoms have led to many models and concepts related to biological clocks that help describe and understand the mechanisms of these changes. Many of the prevailing concepts apply to all organisms, but most of the experimental data are insufficient to explain the dynamics of human biological clocks. This review presents phenomena thai are mainly characteristic ofand unique to - human chronobiology, and which cannot be fully explained by concepts and models drawn from laboratory experiments. We deal with the functional advantages of the human temporal organization and the problem of desynchronization, with special reference to the period (τ) of the circadian rhythm and its interindividual and intraindividual variability. We describe the differences between right- and left-hand rhythms suggesting the existence of different biological clocks in the right and left cortices, Desynchronization of rhythms is rather frequent (one example is night shift workers). In some individuals, desynchronization causes no clinical symptoms and we propose the concept of “allochronism” to designate a variant of the human temporal organization with no pathological implications. We restrict the term “dyschronism” to changes or alterations in temporal organization associated with a set of symptoms similar to those observed in subjects intolerant to shift work, eg, persisting fatigue and mood and sleep alterations. Many diseases involve chronic deprivation of sleep at night and constitute conditions mimicking thai of night shift workers who are intolerant to desynchronization. We also present a genetic model (the dian-circadian model) to explain interindividual differences in the period of biological rhythms in certain conditions. PMID:22033796

  11. Adaptation of sleep and circadian rhythms to the Antarctic summer - A question of zeitgeber strength

    NASA Technical Reports Server (NTRS)

    Gander, Philippa H.; Macdonald, John A.; Montgomery, John C.; Paulin, Michael G.

    1991-01-01

    Adaptation of sleep and circadian rhythms was examined in three temperate zone dwellers arriving in Antarctica during summer. Rectal temperature, wrist activity, and heart rate were monitored continuously, sleep timing and quality noted on awakening, and mood and fatigue rated every 2 h while awake. Sleep was poorer in 2/3 subjects in Antarctica, where all subjects reported more difficulty rising. Sleep occurred at the same clock times in New Zealand and Antarctica, however, the rhythms of temperature, activity, and heart rate underwent a delay of about of 2 h. The subject with the most Antarctic experience had the least difficulty adapting to sleeping during constant daylight. The subject with the most delayed circadian rhythms had the most difficulty. The delay in the circadian system with respect to sleep and clock time is hypothesized to be due to differences in zeitgeber strength and/or zeitgeber exposure between Antarctica and New Zealand.

  12. Urinary Cortisol Circadian Rhythm in a Group of High-Functioning Children with Autism.

    ERIC Educational Resources Information Center

    Richdale, Amanda L.; Prior, Margot R.

    1992-01-01

    This study found no evidence for abnormal temporal placement of the basal urinary cortisol circadian rhythm in a group of 18 high-functioning children (ages 4-14) with autism. There was a tendency toward cortisol hypersecretion during the day, predominantly in autistic children who were integrated into the normal school system. (Author/JDD)

  13. A Comparative Study of Circadian Rhythm Functioning and Sleep in People with Asperger Syndrome

    ERIC Educational Resources Information Center

    Hare, Dougal Julian; Jones, Steven; Evershed, Kate

    2006-01-01

    The circadian rhythm functioning and sleep patterns of 10 adults with Asperger syndrome were investigated using actigraphy. When compared with data from neurotypical adults, both statistical and clinically significant differences were found between the two groups, with the adults with Asperger syndrome showing marked abnormalities in both the…

  14. Evidence of a Faster Posterior Dominant EEG Rhythm in Children with Autism

    ERIC Educational Resources Information Center

    Gregory, Michael D.; Mandelbaum, David E.

    2012-01-01

    Multiple electroencephalography (EEG) abnormalities have been associated with autism. In the course of clinical work, we have observed a posterior dominant EEG rhythm at higher frequency in children with autism. To test this observation, 56 EEG tracings of children with autism were compared to the EEGs of age-matched controls. Children with autism…

  15. Heart Health - Brave Heart

    MedlinePlus

    ... 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 ...

  16. Sleep Apnea May Raise Heart Risks in People with Pacemakers

    MedlinePlus

    ... risk for a dangerous heart rhythm disorder called atrial fibrillation, a new study suggests. With sleep apnea, breathing ... sleep disorder is a known risk factor for atrial fibrillation, but the risk for pacemaker patients with sleep ...

  17. Heart transplant

    MedlinePlus

    ... 10 years. Alternative Names Cardiac transplant; Transplant - heart; Transplantation - heart Images Heart, section through the middle Heart, ... 28. Bernstein D. Pediatric heart and heart-lung transplantation. In: Kliegman RM, Behrman RE, Jenson HB, Stanton ...

  18. Heart Failure

    MedlinePlus

    ... version of this page please turn Javascript on. Heart Failure What is Heart Failure? In heart failure, the heart cannot pump enough ... failure often experience tiredness and shortness of breath. Heart Failure is Serious Heart failure is a serious and ...

  19. Heart Disease Down Among Over-40 Americans

    MedlinePlus

    ... risk factors is likely why the rates of heart disease are coming down. These factors include high blood pressure, abnormal cholesterol, smoking, diabetes, overweight and obesity. The rates of high blood pressure and abnormal cholesterol haven' ...

  20. Temporal Interactions between Cortical Rhythms

    PubMed Central

    Roopun, Anita K.; Kramer, Mark A.; Carracedo, Lucy M.; Kaiser, Marcus; Davies, Ceri H.; Traub, Roger D.; Kopell, Nancy J.; Whittington, Miles A.

    2008-01-01

    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 co-active 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. PMID:19225587

  1. Circadian Rhythm Control: Neurophysiological Investigations

    NASA Technical Reports Server (NTRS)

    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.

  2. When a Heart Murmur Signals Valve Disease

    MedlinePlus

    ... in adults may be related to: Valve calcification Endocarditis Rheumatic fever In children, abnormal heart murmurs may ... Problem: Pulmonary Valve Regurgitation Heart Valves and Infective Endocarditis • Risks, Signs and Symptoms • Accurate Diagnosis • Treatment Options • ...

  3. Biological Rhythms in the Skin

    PubMed Central

    Matsui, Mary S.; Pelle, Edward; Dong, Kelly; Pernodet, Nadine

    2016-01-01

    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. PMID:27231897

  4. Biological Rhythms in the Skin.

    PubMed

    Matsui, Mary S; Pelle, Edward; Dong, Kelly; Pernodet, Nadine

    2016-01-01

    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. PMID:27231897

  5. Neurophysiological and Computational Principles of Cortical Rhythms in Cognition

    PubMed Central

    Wang, Xiao-Jing

    2010-01-01

    Synchronous rhythms represent a core mechanism for sculpting temporal coordination of neural activity in the brainwide network. This review focuses on oscillations in the cerebral cortex that occur during cognition, in alert behaving conditions. Over the last two decades, experimental and modeling work has made great strides in elucidating the detailed cellular and circuit basis of these rhythms, particularly gamma and theta rhythms. The underlying physiological mechanisms are diverse (ranging from resonance and pacemaker properties of single cells, to multiple scenarios for population synchronization and wave propagation), but also exhibit unifying principles. A major conceptual advance was the realization that synaptic inhibition plays a fundamental role in rhythmogenesis, either in an interneuronal network or in a recipropocal excitatory-inhibitory loop. Computational functions of synchronous oscillations in cognition are still a matter of debate among systems neuroscientists, in part because the notion of regular oscillation seems to contradict the common observation that spiking discharges of individual neurons in the cortex are highly stochastic and far from being clock-like. However, recent findings have led to a framework that goes beyond the conventional theory of coupled oscillators, and reconciles the apparent dichotomy between irregular single neuron activity and field potential oscillations. From this perspective, a plethora of studies will be reviewed on the involvement of long-distance neuronal coherence in cognitive functions such as multisensory integration, working memory and selective attention. Finally, implications of abnormal neural synchronization are discussed as they relate to mental disorders like schizophrenia and autism. PMID:20664082

  6. Effects of chronic administration and withdrawal of antidepressant agents on circadian activity rhythms in rats.

    PubMed

    Wollnik, F

    1992-10-01

    Experimental and clinical studies indicate that clinical depression may be associated with disturbances of circadian rhythms. To explore the interaction between circadian rhythmicity, behavioral state, and monoaminergic systems, the present study investigated the effects of chronic administration and withdrawal of the following antidepressant agents on circadian wheel-running rhythms of laboratory rats: a) moclobemide, a reversible and selective monoamine oxidase (MAO) type A inhibitor; b) Ro 19-6327, a selective MAO type B inhibitor; c) desipramine, a preferential norepinephrine reuptake inhibitor; d) clomipramine and e) fluoxetine, both serotonin reuptake inhibitors; and f) levoprotiline, an atypical antidepressant whose biochemical mechanism is still unknown. Wheel-running activity rhythms were studied in three inbred strains of laboratory rats (ACI, BH, LEW) under constant darkness (DD). Two of these inbred strains (BH and LEW) show profound abnormalities in their circadian activity rhythms, namely, a reduced overall level of activity and bimodal or multimodal activity patterns. Chronic treatment with moclobemide and desipramine consistently increased the overall level, as well as the circadian amplitude, of the activity rhythm. Furthermore, the abnormal activity pattern of the LEW strain was changed into a unimodal activity pattern like that of other laboratory rats. The free-running period tau was slightly shortened by moclobemide and dramatically shortened by desipramine. Effects of moclobemide and desipramine treatment on overall activity level and duration were reversed shortly after termination of treatment, whereas long aftereffects were observed for the free-running period. All other substances tested had no systematic effects on the activity rhythms of any of the strains. The fact that moclobemide and desipramine altered the period, amplitude, and pattern of circadian activity rhythms is consistent with the hypothesis that monoaminergic transmitters

  7. Clinical and histological predictive risk factors of atrial fibrillation in patients undergoing open-heart surgery

    PubMed Central

    TINICA, GRIGORE; MOCANU, VERONICA; ZUGUN-ELOAE, FLORIN; BUTCOVAN, DOINA

    2015-01-01

    Postoperative atrial fibrillation (POAF) is a common complication subsequent to cardiac surgery. Various risk factors have been reported for the development of this complication; however, their precise role in POAF is unknown. In the present study, we attempted to identify clinical factors and histopathological changes in atrial tissue that may predict the development of POAF. Atrial tissue was sampled from 103 patients in sinus rhythm that had undergone open-heart surgery, including elective coronary artery bypass grafting (79.61%) and heart valve surgery (20.38%). Atrial surgical biopsies were obtained from the right atrial appendage at the site of cannulation, prior to cardiopulmonary bypass. Tissues were processed routinely for light microscopy, then stained with hematoxylin and eosin and sirius red. Microscopical exams were used to observe the atrial lesions and morphometry was conducted for quantification. In total, 37 patients (35.92%) developed POAF and atrial lesions were identified in the majority of patients in the normal postoperative sinus rhythm and POAF groups, but were most common in the POAF patients. The most common risk factors involved in developing POAF were found to be: Age of >60 years, male gender, ejection fraction of <50% and increased pulmonary hypertension. Furthermore, interstitial fibrosis and myocytolysis were the most common injuries identified. Abnormalities in atrial surgical biopsies may indicate the susceptibility of a patient to developing POAF. The present results suggest that the pre-existent alterations in the structure of the right atrium may be a major determinant in the development of POAF. PMID:26668632

  8. Resting state Rolandic mu rhythms are related to activity of sympathetic component of autonomic nervous system in healthy humans.

    PubMed

    Triggiani, Antonio Ivano; Valenzano, Anna; Del Percio, Claudio; Marzano, Nicola; Soricelli, Andrea; Petito, Annamaria; Bellomo, Antonello; Başar, Erol; Mundi, Ciro; Cibelli, Giuseppe; Babiloni, Claudio

    2016-05-01

    We tested the hypothesis of a relationship between heart rate variability (HRV) and Rolandic mu rhythms in relaxed condition of resting state. Resting state eyes-closed electroencephalographic (EEG) and electrocardiographic (ECG) data were recorded (10-20 System) in 42 healthy adults. EEG rhythms of interest were high-frequency alpha (10.5-13Hz) and low-frequency beta (13-20Hz), which are supposed to form Rolandic mu rhythms. Rolandic and occipital (control) EEG sources were estimated by LORETA software. Results showed a statistically significant (p<0.05, corrected) negative correlation across all subjects between Rolandic cortical sources of low-frequency beta rhythms and the low-frequency band power (LF, 0.04-0.15Hz) of tachogram spectrum as an index of HRV. The lower the amplitude of Rolandic sources of low-frequency beta rhythms (as a putative sign of activity of somatomotor cortex), the higher the LF band power of tachogram spectrum (as a putative sign of sympathetic activity). This effect was specific as there was neither a similar correlation between these EEG rhythms and high-frequency band power of tachogram spectrum (as a putative sign of parasympathetic vagal activity) neither between occipital sources of low-frequency beta rhythms (as a putative sign of activity of visual cortex) and LF band power of tachogram spectrum. These results suggest that Rolandic low-frequency beta rhythms are related to sympathetic activity regulating heart rate, as a dynamic neurophysiologic oscillatory mechanism sub-serving the interaction between brain neural populations involved in somatomotor control and brain neural populations regulating ANS signals to heart for on-going homeostatic adaptations. PMID:25660308

  9. Electrophysiological actions of somatostatin on the atrioventricular junction in sinus rhythm and reentry tachycardia.

    PubMed Central

    Webb, S C; Krikler, D M; Hendry, W G; Adrian, T E; Bloom, S R

    1986-01-01

    Because somatostatin, a neuroregulatory peptide, is found in abundance in the atria and atrioventricular node, its electrophysiological and antiarrhythmic properties were compared with those of verapamil in ten patients with paroxysmal atrioventricular tachycardia. During sinus rhythm, intravenous somatostatin slowed the heart rate whereas verapamil increased it. Though both agents prolonged atrioventricular conduction time and refractoriness, verapamil was more potent. They were equally effective at terminating reentry atrioventricular tachycardia, restoring sinus rhythm in six of seven patients. Whereas verapamil consistently blocked conduction in the atrioventricular node, somatostatin usually induced ventricular extrasystoles at the time of conversion. Somatostatin may have physiological importance in the neurohumoral control of cardiac impulse formation and conduction. PMID:2875723

  10. Comparison of circadian rhythms in male and female humans

    NASA Technical Reports Server (NTRS)

    Winget, C. M.; Deroshia, C. W.; Vernikos-Danellis, J.; Rosenblatt, W. S.; Hetherington, N. W.

    1977-01-01

    Heart rate (HR) and rectal temperature (RT) data were obtained from 12 female and 27 male subjects. The subjects were housed in a facility where the environment was controlled. Human male and female RT and HR exhibit a circadian rhythm with an excursion of about 1.2 C and 30 beats/min, respectively. The acrophases, amplitudes, and level crossings are only slightly different between the sexes. The male HR and RT circadian wave forms are more stable than those of the females. However, the actual RT and HR of males were always lower than that of females at all time points around the clock. The HR during sleep in females is 15 per cent below the daily mean heart rate and in males, 22 per cent.

  11. Modality effects in rhythm processing: Auditory encoding of visual rhythms is neither obligatory nor automatic.

    PubMed

    McAuley, J Devin; Henry, Molly J

    2010-07-01

    Modality effects in rhythm processing were examined using a tempo judgment paradigm, in which participants made speeding-up or slowing-down judgments for auditory and visual sequences. A key element of stimulus construction was that the expected pattern of tempo judgments for critical test stimuli depended on a beat-based encoding of the sequence. A model-based measure of degree of beat-based encoding computed from the pattern of tempo judgments revealed greater beat sensitivity for auditory rhythms than for visual rhythms. Visual rhythms with prior auditory exposure were more likely to show a pattern of tempo judgments similar to that for auditory rhythms than were visual rhythms without prior auditory exposure, but only for a beat period of 600 msec. Slowing down the rhythms eliminated the effect of prior auditory exposure on visual rhythm processing. Taken together, the findings in this study support the view that auditory rhythms demonstrate an advantage over visual rhythms in beat-based encoding and that the auditory encoding of visual rhythms can be facilitated with prior auditory exposure, but only within a limited temporal range. The broad conclusion from this research is that "hearing visual rhythms" is neither obligatory nor automatic, as was previously claimed by Guttman, Gilroy, and Blake (2005). PMID:20601718

  12. Gravitational considerations with animal rhythms

    NASA Technical Reports Server (NTRS)

    Wunder, C. C.

    1974-01-01

    As established in the laboratory and largely confirmed by others, simulated high-g environments influence growth and development of animals as small as or smaller than baby turtles, sometimes accelerating and sometimes decelerating these processes. High-g environments result in many functional changes or adjustments in feeding, metabolism, circulation, fluid balances, and structures for support, and influence life expectancy. An assembly of equipment suitable for measuring oxygen consumption of small mammals as influenced by chronic centrifugation and/or by day-night rhythms is discussed.

  13. Nonlinear and Stochastic Dynamics in the Heart

    PubMed Central

    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

  14. Aberrant Development of the Suprachiasmatic Nucleus and Circadian Rhythms in Mice Lacking the Homeodomain Protein Six6

    PubMed Central

    Clark, Daniel D.; Gorman, Michael R.; Hatori, Megumi; Meadows, Jason D.; Panda, Satchidananda; Mellon, Pamela L.

    2013-01-01

    The suprachiasmatic nucleus (SCN) of the mammalian hypothalamus is the central pacemaker for peripheral and organismal circadian rhythms. The development of this hypothalamic structure depends on genetic programs throughout embryogenesis. We have investigated the role of the homeodomain transcription factor Six6 in the development of the SCN. We first showed that Six6 mRNA has circadian regulation in the mouse SCN. We then characterized the behavioral activity patterns of Six6-null mice under various photoperiod manipulations and stained their hypothalami using SCN-specific markers. Six6-null mice display abnormal patterns of circadian behavior indicative of SCN abnormalities. The ability of light exposure to reset rhythms correlates with the presence or absence of optic nerves, but all Six6-null mice show irregular rhythms. In contrast, wild-type mice with crushed optic nerves maintain regular rhythms regardless of light exposure. Using immunohistochemistry for arginine vasopressin (AVP), vasoactive intestinal polypeptide (VIP), and β-galactosidase, we demonstrated the lack of these SCN markers in all Six6- null mice regardless of the presence of optic nerve or partial circadian rhythms. Therefore, Six6 is required for the normal development of the SCN, and the Six6-null mouse can mount independent, although irregular, circadian rhythms despite the apparent absence of a histochemically defined SCN. PMID:23382588

  15. Phenotyping Circadian Rhythms in Mice.

    PubMed

    Eckel-Mahan, Kristin; Sassone-Corsi, Paolo

    2015-01-01

    Circadian rhythms take place with a periodicity of 24 hr, temporally following the rotation of the earth around its axis. Examples of circadian rhythms are the sleep/wake cycle, feeding, and hormone secretion. Light powerfully entrains the mammalian clock and assists in keeping animals synchronized to the 24-hour cycle of the earth by activating specific neurons in the "central pacemaker" of the brain, the suprachiasmatic nucleus. Absolute periodicity of an animal can deviate slightly from 24 hr as manifest when an animal is placed into constant dark or "free-running" conditions. Simple measurements of an organism's activity in free-running conditions reveal its intrinsic circadian period. Mice are a particularly useful model for studying circadian rhythmicity due to the ease of genetic manipulation, thus identifying molecular contributors to rhythmicity. Furthermore, their small size allows for monitoring locomotion or activity in their homecage environment with relative ease. Several tasks commonly used to analyze circadian periodicity and plasticity in mice are presented here including the process of entrainment, determination of tau (period length) in free-running conditions, determination of circadian periodicity in response to light disruption (e.g., jet lag studies), and evaluation of clock plasticity in non-24-hour conditions (T-cycles). Studying the properties of circadian periods such as their phase, amplitude, and length in response to photic perturbation, can be particularly useful in understanding how humans respond to jet lag, night shifts, rotating shifts, or other transient or chronic disruption of environmental surroundings. PMID:26331760

  16. Detecting and Correcting Speech Rhythm Errors

    ERIC Educational Resources Information Center

    Yurtbasi, Metin

    2015-01-01

    Every language has its own rhythm. Unlike many other languages in the world, English depends on the correct pronunciation of stressed and unstressed or weakened syllables recurring in the same phrase or sentence. Mastering the rhythm of English makes speaking more effective. Experiments have shown that we tend to hear speech as more rhythmical…

  17. The Incarnate Rhythm of Geometrical Knowing

    ERIC Educational Resources Information Center

    Bautista, Alfredo; Roth, Wolff-Michael

    2012-01-01

    Rhythm is a fundamental dimension of human nature at both biological and social levels. However, existing research literature has not sufficiently investigated its role in mathematical cognition and behavior. The purpose of this article is to bring the concept of "incarnate rhythm" into current discourses in the field of mathematical learning and…

  18. Accelerated idioventricular rhythm during flexible fiberoptic bronchoscopy

    SciTech Connect

    Borgeat, A.; Chiolero, R.; Mosimann, B.; Freeman, J.

    1987-03-01

    We report the case of a patient who developed severe hypoxemia and an unusual arrhythmia, accelerated idioventricular rhythm, during flexible fiberoptic bronchoscopy. Coronary artery disease was subsequently suspected despite an unremarkable history and physical examination, and confirmed by a thallium 201 imaging. The appearance of accelerated idioventricular rhythm during fiberoptic bronchoscopy should raise the possibility of underlying coronary artery disease.

  19. Circadian rhythms in myocardial metabolism and function

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Circadian rhythms in myocardial function and dysfunction are firmly established in both animal models and humans. For example, the incidence of arrhythmias and sudden cardiac death increases when organisms awaken. Such observations have classically been explained by circadian rhythms in neurohumoral...

  20. Diurnal rhythms of visual accommodation and blink responses - Implication for flight-deck visual standards

    NASA Technical Reports Server (NTRS)

    Murphy, M. R.; Randle, R. J.; Williams, B. A.

    1977-01-01

    Possible 24-h variations in accommodation responses were investigated. A recently developed servo-controlled optometer and focus stimulator were used to obtain monocular accommodation response data on four college-age subjects. No 24-h rhythm in accommodation was shown. Heart rate and blink rate also were measured and periodicity analysis showed a mean 24-h rhythm for both; however, blink rate periodograms were significant for only two of the four subjects. Thus, with the qualifications that college students were tested instead of pilots and that they performed monocular laboratory tasks instead of binocular flight-deck tasks, it is concluded that 24-h rhythms in accommodation responses need not be considered in setting visual standards for flight-deck tasks.

  1. Circadian Rhythm Disruption Promotes Lung Tumorigenesis.

    PubMed

    Papagiannakopoulos, Thales; Bauer, Matthew R; Davidson, Shawn M; Heimann, Megan; Subbaraj, Lakshmipriya; Bhutkar, Arjun; Bartlebaugh, Jordan; Vander Heiden, Matthew G; Jacks, Tyler

    2016-08-01

    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. PMID:27476975

  2. Atrial fibrillation in heart failure: catheter and surgical interventional therapies.

    PubMed

    Rabah, Ali; Wazni, Oussama

    2014-05-01

    Atrial fibrillation and heart failure commonly coexist in the same patient. Each may adversely affect the other. Atrial fibrillation leads to heart failure exacerbation, left ventricular function deterioration and an increase in thrombo-embolic risk. Therapeutic options targeting atrial fibrillation in heart failure patients include pharmacological and non-pharmacological means. Pharmacological therapy is directed at either rate control using nodal blocking agents or rhythm control using anti-arrhythmic agents, of which the options are limited in patients with heart failure. The landmark AF-CHF trial did not show any benefit of rhythm control strategy as opposed to rate control in patients with heart failure and atrial fibrillation. However, patients in this trial as well as in others used mostly amiodarone for rhythm control. This might have negated any positive effects of achieving normal sinus rhythm. Non-pharmacological therapy both for rate and rhythm control is appealing. This includes AV node ablation for rate control, catheter ablation of atrial fibrillation and surgical therapy of atrial fibrillation. This review will address non-pharmacologic treatment of AF in heart failure patients. PMID:24132645

  3. Left ventricular partitioning in systolic heart failure subjects: addressing a mechanistic void with current therapies.

    PubMed

    Schäfer, Ulrich

    2016-05-17

    ICD patients with narrow QRS, CRT non-responders, and functional MR patients all have one mechanistic failure mode that is left untreated - the scar left behind following an MI. ICDs, CRTs, and MitraClip implantation are all well-proven therapies, but the Parachute device may address the mechanistic void that remains after each of these therapies has been used and may further improve patients' outcomes. A pooled analysis of 134 subjects was conducted using the first three clinical trials which included subjects with symptomatic ischaemic HF with LV wall motion abnormalities secondary to MI, and an LV ejection fraction less than 40%. The two-year cumulative mortality rate was 12.9%, with 8.7% in the first year and an increment of 4.2% in the second, which is a 53% reduction as compared to the first year. There is a significant proportion of patients with ischaemic heart failure being excluded from cardiac rhythm management (CRT, etc.), leaving a large treatment gap until mechanical support devices (LVAD) or heart transplantation in progressive heart failure are indicated. Along with other heart failure devices, Parachute may be a useful treatment modality, addressing a mechanistic void in the treatment of this disease. Current data support improvements in haemodynamics, functional capacity, six-minute walk distance, quality of life and a promising decline in mortality two years after Parachute implantation. PMID:27174122

  4. Prenatal Ethanol Exposure Alters Core Body Temperature and Corticosterone Rhythms in Adult Male Rats

    PubMed Central

    Handa, Robert J.; Zuloaga, Damian G.; McGivern, Robert F.

    2008-01-01

    Ethanol’s effects on the developing brain include alterations in morphological and biochemistry of the hypothalamus. In order to examine the potential functional consequences of ethanol’s interference with hypothalamic differentiation, we studied the long-term effects of prenatal ethanol exposure on basal circadian rhythms of core body temperature (CBT) and heart rate (HR). We also examined the late afternoon surge in corticosterone (CORT). CBT and HR rhythms were studied in separate groups of animals at 4 months, 8 months and 20 months of age. The normal late-afternoon rise in plasma corticosterone was examined in freely-moving male rats at 6 months of age via an indwelling right-atrial cannula. Results showed that the CBT circadian rhythm exhibited an earlier rise following the nadir of the rhythm in fetal alcohol exposed (FAE) males at all ages compared to controls. At 8 months of age, the amplitude of the CBT circadian rhythm in FAE males was significantly reduced to the level observed in controls at 20 months. No significant effects of prenatal ethanol exposure were observed on basal HR rhythm at any age. The diurnal rise in corticosterone secretion was blunted and prolonged in 6-month-old FAE males compared to controls. Both control groups exhibited a robust surge in corticosterone secretion around the onset of the dark phase of the light cycle, which peaked at 1930 hours. Instead, FAE males exhibited a linear rise beginning in mid afternoon, which peaked at 2130 hours. These results indicate that exposure to ethanol during the period of hypothalamic development can alter the long-term regulation of circadian rhythms in specific physiological systems. PMID:18047910

  5. Craniosacral rhythm: reliability and relationships with cardiac and respiratory rates.

    PubMed

    Hanten, W P; Dawson, D D; Iwata, M; Seiden, M; Whitten, F G; Zink, T

    1998-03-01

    Craniosacral rhythm (CSR) has long been the subject of debate, both over its existence and its use as a therapeutic tool in evaluation and treatment. Origins of this rhythm are unknown, and palpatory findings lack scientific support. The purpose of this study was to determine the intra- and inter-examiner reliabilities of the palpation of the rate of the CSR and the relationship between the rate of the CSR and the heart or respiratory rates of subjects and examiners. The rates of the CSR of 40 healthy adults were palpated twice by each of two examiners. The heart and respiratory rates of the examiners and the subjects were recorded while the rates of the subjects' CSR were palpated by the examiners. Intraclass correlation coefficients were calculated to determine the intra- and inter-examiner reliabilities of the palpation. Two multiple regression analyses, one for each examiner, were conducted to analyze the relationships between the rate of the CSR and the heart and respiratory rates of the subjects and the examiners. The intraexaminer reliability coefficients were 0.78 for examiner A and 0.83 for examiner B, and the interexaminer reliability coefficient was 0.22. The result of the multiple regression analysis for examiner A was R = 0.46 and adjusted R2 = 0.12 (p = 0.078) and for examiner B was R = 0.63 and adjusted R2 = 0.32 (p = 0.001). The highest bivariate correlation was found between the CSR and the subject's heart rate (r = 0.30) for examiner A and between the CSR and the examiner's heart rate (r = 0.42) for examiner B. The results indicated that a single examiner may be able to palpate the rate of the CSR consistently, if that is what we truly measured. It is possible that the perception of CSR is illusory. The rate of the CSR palpated by two examiners is not consistent. The results of the regression analysis of one examiner offered no validation to those of the other. It appears that a subject's CSR is not related to the heart or respiratory rates of the

  6. Blood pressure, pulse rate, and rhythm measurement using ionic polymer-metal composite sensors

    NASA Astrophysics Data System (ADS)

    Keshavarzi, Amid; Shahinpoor, Mohsen; Kim, Kwang J.; Lantz, Jeffrey W.

    1999-05-01

    The need for more enhanced blood pressure (BP), pulse rate and rhythm senors has given rise to the possibility of using ionic polymer-metal composites (IPMCs) sensors. In this study we propose to use the IPMC sensors to measure systolic and diastolic BP, pulse rate and rhythm. The proposed IPMC sensors take advantage of the endo-ionic mobility within the polymer- metal composite by converting normal and shear load inputs into an induced voltage output across the thickness of the IPMC sensor. The fabricated IPMC sensors are suitable to be installed on the inner surface of a cuff and, therefore, both systolic and diastolic BP, pulse rate, and rhythm can be measured. An added benefit is the ability of measuring 'pulse rhythm' which give a more amplified look at heart irregularities which a typical pulse rate sensor is unable to show. Our data shows IPMC sensors can produce consistent and reliable BP readings, pulse rate, and rhythm. Typically, a linear relationship between applied maximum load and induced maximum voltage was obtained. This result can be easily translated into good BP reading.

  7. Circadian rhythms: glucocorticoids and arthritis.

    PubMed

    Cutolo, Maurizio; Sulli, Alberto; Pizzorni, Carmen; Secchi, Maria Elena; Soldano, Stefano; Seriolo, Bruno; Straub, Rainer H; Otsa, Kati; Maestroni, Georges J

    2006-06-01

    Circadian rhythms are driven by biological clocks and are endogenous in origin. Therefore, circadian changes in the metabolism or secretion of endogenous glucocorticoids are certainly responsible in part for the time-dependent changes observed in the inflammatory response and arthritis. More recently, melatonin (MLT), another circadian hormone that is the secretory product of the pineal gland, has been found implicated in the time-dependent inflammatory reaction with effects opposite those of cortisol. Interestingly, cortisol and MLT show an opposite response to the light. The light conditions in the early morning have a strong impact on the morning cortisol peak, whereas MLT is synthesized in a strictly nocturnal pattern. Recently, a diurnal rhythmicity in healthy humans between cellular (Th1 type) or humoral (Th2 type) immune responses has been found and related to immunomodulatory actions of cortisol and MLT. The interferon (IFN)-gamma/interleukin (IL)-10 ratio peaked during the early morning and correlated negatively with plasma cortisol and positively with plasma MLT. Accordingly, the intensity of the arthritic pain varies consistently as a function of the hour of the day: pain is greater after waking up in the morning than in the afternoon or evening. The reduced cortisol and adrenal androgen secretion, observed during testing in rheumatoid arthritis (RA) patients not treated with glucocoticoids, should be clearly considered as a "relative adrenal insufficiency" in the presence of a sustained inflammatory process, and allows Th1 type cytokines to be produced in higher amounts during the late night. In conclusion, the right timing (early morning) for the glucocorticoid therapy in arthritis is fundamental and well justified by the circadian rhythms of the inflammatory mechanisms. PMID:16855156

  8. Phenotyping Circadian Rhythms in Mice

    PubMed Central

    Eckel-Mahan, Kristin; Sassone-Corsi, Paolo

    2015-01-01

    Circadian rhythms take place with a periodicity of twenty-four hours, temporally following the rotation of the earth around its axis. Examples of circadian rhythms are the sleep/wake cycle, feeding, and hormone secretion. Light powerfully entrains the mammalian clock and assists in keeping animals synchronized to the 24-hour cycle of the earth by activating specific neurons in the “central pacemaker” of the brain, the suprachiasmatic nucleus. Absolute periodicity of an animal can deviate slightly from 24 hours as manifest when an animal is placed into constant dark- or “free running”- conditions. Simple measurements of an organism's activity in free running conditions reveal its intrinsic circadian period. Mice are a particularly useful model for studying circadian rhythmicity due to the ease of genetic manipulation, thus identifying molecular contributors to rhythmicity. Furthermore, their small size allows for monitoring locomotion or activity in their home cage environment with relative ease. Several tasks commonly used to analyze circadian periodicity and plasticity in mice are outlined here including the process of entrainment, determination of tau (period length) in free running conditions, determination of circadian periodicity in response to light disruption (i.e. jet lag studies), and evaluation of clock plasticity in non-twenty-four hour conditions (T-cycles). Studying the properties of circadian periods such as their phase, amplitude, and length in response to photic perturbation, can be particularly useful in understanding how humans respond to jet lag, night shifts, rotating shifts, or other transient or chronic disruption of one's environmental surroundings. PMID:26331760

  9. Heart rate turbulence.

    PubMed

    Cygankiewicz, Iwona

    2013-01-01

    Heart rate turbulence (HRT) is a baroreflex-mediated biphasic reaction of heart rate in response to premature ventricular beats. Heart rate turbulence is quantified by: turbulence onset (TO) reflecting the initial acceleration of heart rate following premature beat and turbulence slope (TS) describing subsequent deceleration of heart rate. Abnormal HRT identifies patients with autonomic dysfunction or impaired baroreflex sensitivity due to variety of disorders, but also may reflect changes in autonomic nervous system induced by different therapeutic modalities such as drugs, revascularization, or cardiac resynchronization therapy. More importantly, impaired HRT has been shown to identify patients at high risk of all-cause mortality and sudden death, particularly in postinfarction and congestive heart failure patients. It should be emphasized that abnormal HRT has a well-established role in stratification of postinfarction and heart failure patients with relatively preserved left ventricular ejection fraction. The ongoing clinical trials will document whether HRT can be used to guide implantation of cardioverter-defibrillators in this subset of patients, not covered yet by ICD guidelines. This review focuses on the current state-of-the-art knowledge regarding clinical significance of HRT in detection of autonomic dysfunction and regarding the prognostic significance of this parameter in predicting all-cause mortality and sudden death. PMID:24215748

  10. Resting and Task-Modulated High-Frequency Brain Rhythms Measured by Scalp Encephalography in Infants with Tuberous Sclerosis Complex

    ERIC Educational Resources Information Center

    Stamoulis, Catherine; Vogel-Farley, Vanessa; Degregorio, Geneva; Jeste, Shafali S.; Nelson, Charles A.

    2015-01-01

    The electrophysiological correlates of cognitive deficits in tuberous sclerosis complex (TSC) are not well understood, and modulations of neural dynamics by neuroanatomical abnormalities that characterize the disorder remain elusive. Neural oscillations (rhythms) are a fundamental aspect of brain function, and have dominant frequencies in a wide…

  11. Irregular Sleep-Wake Rhythm Disorder.

    PubMed

    Abbott, Sabra M; Zee, Phyllis C

    2015-12-01

    Irregular sleep-wake rhythm disorder is a circadian rhythm disorder characterized by multiple bouts of sleep within a 24-hour period. Patients present with symptoms of insomnia, including difficulty either falling or staying asleep, and daytime excessive sleepiness. The disorder is seen in a variety of individuals, ranging from children with neurodevelopmental disorders, to patients with psychiatric disorders, and most commonly in older adults with neurodegenerative disorders. Treatment of irregular sleep-wake rhythm disorder requires a multimodal approach aimed at strengthening circadian synchronizing agents, such as daytime exposure to bright light, and structured social and physical activities. In addition, melatonin may be useful in some patients. PMID:26568126

  12. Musical alexia for rhythm notation: a discrepancy between pitch and rhythm.

    PubMed

    Midorikawa, Akira; Kawamura, Mitsuru; Kezuka, Machiko

    2003-06-01

    In the process of reading music, the reading of rhythm and pitch might be differentiated, although there is no evidence of this to date. There have been cases of disorders restricted to the reading of pitch, but none in which the disorder has been restricted to the reading of rhythm. We present a case of musical alexia and agraphia with Wernicke's aphasia. An in-depth assessment of the subject's musical reading ability showed that her musical alexia was restricted to unfamiliar melodies. When a melody was divided into rhythm elements and pitch elements, pitch reading was preserved, but rhythm reading was severely disturbed. This is the first case reported of a disorder restricted to rhythm reading, and suggests the independence of rhythm reading and pitch reading. PMID:12925929

  13. The effect of restraining on the heart rate in guinea pigs

    NASA Technical Reports Server (NTRS)

    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.

  14. CIRCADIAN RHYTHM REPROGRAMMING DURING LUNG INFLAMMATION

    PubMed Central

    Haspel, Jeffrey A.; Chettimada, Sukrutha; Shaik, Rahamthulla S.; Chu, Jen-Hwa; Raby, Benjamin A.; Cernadas, Manuela; Carey, Vincent; Process, Vanessa; Hunninghake, G. Matthew; Ifedigbo, Emeka; Lederer, James A.; Englert, Joshua; Pelton, Ashley; Coronata, Anna; Fredenburgh, Laura E.; Choi, Augustine M. K.

    2014-01-01

    Circadian rhythms are known to regulate immune responses in healthy animals, but it is unclear whether they persist during acute illnesses where clock gene expression is disrupted by systemic inflammation. Here, we use a genome-wide approach to investigate circadian gene and metabolite expression in the lungs of endotoxemic mice and find that novel cellular and molecular circadian rhythms are elicited in this setting. The endotoxin-specific circadian program exhibits unique features, including a divergent group of rhythmic genes and metabolites compared to the basal state and a distinct periodicity and phase distribution. At the cellular level endotoxin treatment also alters circadian rhythms of leukocyte counts within the lung in a bmal1-dependent manner, such that granulocytes rather than lymphocytes become the dominant oscillating cell type. Our results show that inflammation produces a complex reorganization of cellular and molecular circadian rhythms that are relevant to early events in lung injury. PMID:25208554

  15. Metrical perception of trisyllabic speech rhythms.

    PubMed

    Benadon, Fernando

    2014-01-01

    The perception of duration-based syllabic rhythm was examined within a metrical framework. Participants assessed the duration patterns of four-syllable phrases set within the stress structure XxxX (an Abercrombian trisyllabic foot). Using on-screen sliders, participants created percussive sequences that imitated speech rhythms and analogous non-speech monotone rhythms. There was a tendency to equalize the interval durations for speech stimuli but not for non-speech. Despite the perceptual regularization of syllable durations, different speech phrases were conceived in various rhythmic configurations, pointing to a diversity of perceived meters in speech. In addition, imitations of speech stimuli showed more variability than those of non-speech. Rhythmically skilled listeners exhibited lower variability and were more consistent with vowel-centric estimates when assessing speech stimuli. These findings enable new connections between meter- and duration-based models of speech rhythm perception. PMID:23417710

  16. Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure

    PubMed Central

    Bonmati-Carrion, Maria Angeles; Arguelles-Prieto, Raquel; Martinez-Madrid, Maria Jose; Reiter, Russel; Hardeland, Ruediger; Rol, Maria Angeles; Madrid, Juan Antonio

    2014-01-01

    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. PMID:25526564

  17. Spontaneous Group Synchronization of Movements and Respiratory Rhythms

    PubMed Central

    Vandoni, Matteo; Bernardi, Luciano

    2014-01-01

    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. PMID:25216280

  18. Nuclear receptors linking circadian rhythms and cardiometabolic control

    PubMed Central

    Duez, Hélène; Staels, Bart

    2010-01-01

    Many behavioral and physiological processes, including locomotor activity, blood pressure, body temperature, sleep(fasting)/wake(feeding) cycles as well as metabolic regulation display diurnal rhythms. The biological clock ensures proper metabolic alignment of energy substrate availability and processing. Studies in animals and humans highlight a strong link between circadian disorders and altered metabolic responses and cardiovascular events. Shiftwork, for instance, increases the risk to develop metabolic abnormalities resembling the Metabolic Syndrome. Nuclear receptors have long been known as metabolic regulators. Several of them (ie. Rev-erbα, RORα, PPARs) are subjected to circadian variations and are integral components of the molecular clock machinery. In turn, these nuclear receptors regulate downstream target genes in a circadian manner, acting to properly gate metabolic events to the appropriate circadian time window. PMID:20631353

  19. Circadian rhythms in cardiac arrhythmias and opportunities for their chronotherapy.

    PubMed

    Portaluppi, Francesco; Hermida, Ramón C

    2007-08-31

    It is now well established that nearly all functions of the body, including those that influence the pharmacokinetics and pharmacodynamics of medications, exhibit significant 24-hour variation. The electrical properties of the heart as well as cardiac arrhythmias also vary as circadian rhythms, even though the suboptimal methods initially used for their investigation slowed their identification and thorough characterization. The application of continuous Holter monitoring of the electrical properties of the heart has revealed 24-hour variation in the occurrence of ventricular premature beats with the peak in events, in diurnally active persons, between 6 a.m. and noon. After the introduction of implantable cardioverter-defibrillators, ventricular tachycardia or fibrillation were also found to peak in the same period of the day. Even defibrillator energy requirements show circadian variation, thus supporting the need for a temporal awareness in the therapeutic approach to arrhythmias. Imbalanced autonomic tone, circulating levels of catecholamines, increased heart rate and blood pressure, all established determinants of cardiac arrhythmias, show circadian variations and underlie the genesis of the circadian pattern of cardiac arrhythmias. Arrhythmogenesis appears to be suppressed during nighttime sleep, and this can influence the evaluation of the efficacy of antiarrhythmic medications in relation to their administration time. Unfortunately, very few studies have been undertaken to assess the proper timing (chronotherapy) of antiarrhythmic medications as means to maximize efficacy and possibly reduce side effects. Further research in this field is warranted and could bring new insight and clinical advantage. PMID:17659808

  20. Do changes in subjective sleep and biological rhythms predict worsening in postpartum depressive symptoms? A prospective study across the perinatal period.

    PubMed

    Krawczak, Elizabeth M; Minuzzi, Luciano; Hidalgo, Maria Paz; Frey, Benicio N

    2016-08-01

    Abnormalities of sleep and biological rhythms have been widely implicated in the pathophysiology of major depressive disorder (MDD) and bipolar disorder (BD). However, less is known about the influence of biological rhythm disruptions across the perinatal period on postpartum depression (PPD). The objective of this study was to prospectively evaluate the relationship between subjective changes in both sleep and biological rhythms and worsening of depressive symptoms from pregnancy to the postpartum period in women with and without mood disorders. Eighty-three participants (38 euthymic women with a history of a mood disorder and 45 healthy controls) were studied. Participants completed subjective assessments of sleep (Pittsburgh Sleep Quality Index), biological rhythm disturbances (Biological Rhythms Interview of Assessment in Neuropsychiatry), and depressive symptoms (Edinburgh Postnatal Depression Scale) prospectively at two time points: third trimester of pregnancy and at 6-12 weeks postpartum. Multivariate regression analyses showed that changes in biological rhythms across the perinatal period predicted worsening of depressive symptoms in both groups. Moreover, women with a history of a mood disorder showed higher levels of sleep and biological rhythm disruption during both pregnancy and the postpartum period. These findings suggest that disruptions in biological rhythms during the perinatal period increase the risk for postpartum mood worsening in healthy pregnant as well as in pregnant women with a history of mood disorders. PMID:26920913

  1. Neuroanatomy of the Extended Circadian Rhythm System

    PubMed Central

    Morin, Lawrence P

    2012-01-01

    The suprachiasmatic nucleus (SCN), site of the primary clock in the circadian rhythm system, has three major afferent connections. The most important consists of a retinohypothalamic projection through which photic information, received by classical rod/cone photoreceptors and intrinsically photoreceptive retinal ganglion cells, gains access to the clock. This information influences phase and period of circadian rhythms. The two other robust afferent projections are the median raphe serotonergic pathway and the geniculohypothalamic (GHT), NPY-containing pathway from the thalamic intergeniculate leaflet (IGL). Beyond this simple framework, the number of anatomical routes that could theoretically be involved in rhythm regulation is enormous, with the SCN projecting to 15 regions and being directly innervated by about 35. If multisynaptic afferents to the SCN are included, the number expands to approximately brain 85 areas providing input to the SCN. The IGL, a known contributor to circadian rhythm regulation, has a still greater level of complexity. This nucleus connects abundantly throughout the brain (to approximately 100 regions) by pathways that are largely bilateral and reciprocal. Few of these sites have been evaluated for their contributions to circadian rhythm regulation, although most have a theoretical possibility of doing so via the GHT. The anatomy of IGL connections suggests that one of its functions may be regulation of eye movements during sleep. Together, neural circuits of the SCN and IGL are complex and interconnected. As yet, few have been tested with respect to their involvement in rhythm regulation. PMID:22766204

  2. Circadian rhythms and cancer chemotherapy.

    PubMed

    Wood, P A; Hrushesky, W J

    1996-01-01

    Temporal coordination of biologic processes with an approximately 24-h cycle (circadian) is common throughout the animal and plant kingdom and even in some prokaryotic organisms. In all organisms studied, the capability to keep biologic time is an inherited characteristic located intracellularly. These biological clocks anticipate and get the organism ready for regular environmental changes. This indicates both the ubiquity and the weight of the selective environmental pressure to keep time accurately. Several molecular strategies for biologic time keeping have apparently arisen independently several times throughout evolution. The anatomic, biochemical, and molecular mechanisms of the clock are in the process of being defined. This temporal organization at the cellular, organ, and organismic levels results in predictable differences in the capacity of plants, animals, and human beings to respond to therapeutic interventions administered at different times throughout important biologic cycles (e.g., circadian timed therapy). In the treatment of the cancer bearing host, circadian timing of surgery, anticancer drugs, radiation therapy, and biologic agents can result in improved toxicity profiles, enhanced tumor control, and improved host survival. The routine clinical application of such principles is facilitated by the availability of programmable drug delivery devices. Rhythm frequency ranges other than 24-h (e.g., low frequency: menstrual; high frequency: 10 to 120 min) may also be important to understanding health and disease and to designing successful therapy in diseases as diverse as cancer, infertility, and diabetes. PMID:8959371

  3. The role of feeding rhythm, adrenal hormones and neuronal inputs in synchronizing daily clock gene rhythms in the liver.

    PubMed

    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. PMID:26704081

  4. Altered brain rhythms and functional network disruptions involved in patients with generalized fixation-off epilepsy.

    PubMed

    Solana, Ana Beatriz; Martínez, Kenia; Hernández-Tamames, Juan Antonio; San Antonio-Arce, Victoria; Toledano, Rafael; García-Morales, Irene; Alvárez-Linera, Juan; Gil-Nágel, Antonio; Del Pozo, Francisco

    2016-06-01

    Generalized Fixation-off Sensitivity (CGE-FoS) patients present abnormal EEG patterns when losing fixation. In the present work, we studied two CGE-FoS epileptic patients with simultaneous EEG-fMRI. We aim to identify brain areas that are specifically related to the pathology by identifying the brain networks that are related to the EEG brain altered rhythms. Three main analyses were performed: EEG standalone, where the voltage fluctuations in delta, alpha, and beta EEG bands were obtained; fMRI standalone, where resting-state fMRI ICA analyses for opened and closed eyes conditions were computed per subject; and, EEG-informed fMRI, where EEG delta, alpha and beta oscillations were used to analyze fMRI. Patient 1 showed EEG abnormalities for lower beta band EEG brain rhythm. Fluctuations of this rhythm were correlated with a brain network mainly composed by temporo-frontal areas only found in the closed eyes condition. Patient 2 presented alterations in all the EEG brain rhythms (delta, alpha, beta) under study when closing eyes. Several biologically relevant brain networks highly correlated (r > 0.7) to each other in the closed eyes condition were found. EEG-informed fMRI results in patient 2 showed hypersynchronized patterns in the fMRI correlation spatial maps. The obtained findings allow a differential diagnosis for each patient and different profiles with respect to healthy volunteers. The results suggest a different disruption in the functional brain networks of these patients that depends on their altered brain rhythms. This knowledge could be used to treat these patients by novel brain stimulation approaches targeting specific altered brain networks in each patient. PMID:26001771

  5. Monitoring chaos of cardiac rhythms

    SciTech Connect

    Mayer-Kress, G.

    1989-01-01

    Chaos theory provides a new paradigm in monitoring complexity changes in heart rate variability. Even in cases where the spectral analysis only shows broad band characteristics estimations of dimensional complexity parameters can show quantitative changes in the degree of chaos present in the interbeat interval dynamics. We introduce the concept of dimensional complexity as dynamical monitoring parameter and discuss its properties in connection with control data and data taken during cardiac arrest. Whereas dimensional complexity provides a quantitative indicator of overall chaotic behavior, recurrence plots allow direct visualization of recurrences in arbitrary high dimensional pattern-space. In combination these two methods from non-linear dynamics exemplify a new approach in the problem of heart rate monitoring and identification of precursors of cardiac arrest. Finally we mention a new method of chaotic control, by which selective and highly effective perturbations of nonlinear dynamical systems could be used for improved pacing patterns. 11 refs., 6 figs.

  6. Abnormal Head Position

    MedlinePlus

    ... cause. Can a longstanding head turn lead to any permanent problems? Yes, a significant abnormal head posture could cause permanent ... occipitocervical synostosis and unilateral hearing loss. Are there any ... postures? Yes. Abnormal head postures can usually be improved depending ...

  7. Urine - abnormal color

    MedlinePlus

    ... straw-yellow. Abnormally colored urine may be cloudy, dark, or blood-colored. Causes Abnormal urine color may ... red blood cells, or mucus in the urine. Dark brown but clear urine is a sign of ...

  8. 42 CFR 37.53 - Notification of abnormal roentgenographic findings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... suggesting, enlarged heart, tuberculosis, lung cancer, or any other significant abnormal findings other than... to the miner by MSHA in accordance with section 203 of the act (see 30 CFR part 90). Positive... files and the most recent examination was interpreted to show enlarged heart, tuberculosis,...

  9. [Ventricular pre-excitation revealed by idioventricular rhythm and large QRS tachycardias. Apropos of an operated case].

    PubMed

    Weissenburger, J; Dumoulin, P; Juliard, J M; Frank, R; Kessler, P; Michel, P L; Rozensztajn, L; Valty, J

    1983-06-01

    A 15 year old boy presented with palpitations of sudden onset and termination over a two month period. The heart was clinically and radiologically normal. The electrocardiogramme showed sinus rhythm with a short PR interval (0,11 sec) and narrow QRS complexes (0,08 sec) associated with an intermittent escape accelerated idioventricular rhythm (AIVR). During an attack of palpitations a regular tachycardia (250/min) with wide QRS complexes of the same configuration as those of the AIVR (left side delay). The diagnosis of ventricular tachycardia was retained. Endocavitary electrophysiological recording demonstrated preexcitation of the right ventricle associated with accelerated nodal conduction explaining the narrow QRS complexes in sinus rhythm. The wide complex tachycardias initiated and terminated by paired ventricular stimulation were identical to the spontaneous attacks and were attributed to an antidromic reciprocating rhythm. The hypothesis of a rhythm arising from the accessory pathway is suggested. This would explain the identical configuration of the QRS complexes of the AIVR and of the antidromic reciprocating-rhythm and the disappearance of the AIVR after surgical section of the accessory pathway. PMID:6414416

  10. Dysregulation of neuroendocrine crossroads: depression, circadian rhythms and the retina--a hypothesis.

    PubMed

    Steiner, M; Werstiuk, E S; Seggie, J

    1987-01-01

    The pathophysiology of depression and the mechanism of action of lithium and other antidepressant drugs involve alterations in circadian rhythms. These include changes in both the intrinsic rhythm of circadian oscillators and in the sensitivity of the retina to LIGHT. The retina in humans is the only photoreceptor for circadian entrainment. The retinal-hypothalamic-pineal axis is the essential pathway for neuronal entrainment of rhythms which use light as a phase cue. A common substance throughout this axis in many species is MELATONIN. Retinal melatonin has been implicated in regulation of the sensitivity of the retina to light. The hypothalamus, at THE NEUROENDOCRINE CROSSROADS, has a central role in the integration of neurotransmitters and hormones in circadian rhythms. DYSREGULATION of the hypothalamic-pituitary-adrenal, as well as -gonadal, axes has been documented in depressed patients. Abnormalities in circulating melatonin have also been found in patients with affective disorders. It is speculated that the availability of melatonin along the retinal-hypothalamic-pineal axis may have important implications in the genesis of affective disorders. More specifically--is there a latent biochemical defect which causes a phase shift and change in circadian rhythms of melatonin and/or other neurotransmitters in the retina which then alters the sensitivity of the retina to light (for the visible spectrum) which in turn desynchronizes all other biological rhythms thus disrupting mental well-being? We suggest that variations of retinal photosensitivity in humans can be measured by using a visual testing system, and that depressed patients might show changes in photosensitivity which could be corrected when treated with lithium and/or antidepressants. It is our working hypothesis that the primary defect in depression may be a change in retinal function, and that behavioural and neuroendocrine concomitants of this disorder are secondary events. PMID:2888161

  11. Aortic Valve Disease

    MedlinePlus

    ... Disease Tricuspid Valve Disease Cardiac Rhythm Disturbances Thoracic Aortic Aneurysm Pediatric and Congenital Heart Disease Heart abnormalities that ... Disease Tricuspid Valve Disease Cardiac Rhythm Disturbances Thoracic Aortic Aneurysm Aortic Valve Disease Overview The human heart has ...

  12. If Your Child Has a Heart Defect (For Parents)

    MedlinePlus

    ... septal defect , atrial septal defect , atrioventricular canal, and patent ductus arteriosus). Or the congestion could be the ... for Congenital Heart Defects Many heart abnormalities (including patent ductus arteriosus , ventricular septal defect , truncus arteriosus, atrioventricular ...

  13. Convergent Rhythm Generation from Divergent Cellular Mechanisms

    PubMed Central

    Rodriguez, Jason C.; Blitz, Dawn M.

    2013-01-01

    Different modulatory inputs commonly elicit distinct rhythmic motor patterns from a central pattern generator (CPG), but they can instead elicit the same pattern. We are determining the rhythm-generating mechanisms in this latter situation, using the gastric mill (chewing) CPG in the crab (Cancer borealis) stomatogastric ganglion, where stimulating the projection neuron MCN1 (modulatory commissural neuron 1) or bath applying CabPK (C. borealis pyrokinin) peptide elicits the same gastric mill motor pattern, despite configuring different gastric mill circuits. In both cases, the core rhythm generator includes the same reciprocally inhibitory neurons LG (lateral gastric) and Int1 (interneuron 1), but the pyloric (food-filtering) circuit pacemaker neuron AB (anterior burster) is additionally necessary only for CabPK rhythm generation. MCN1 drives this rhythm generator by activating in the LG neuron the modulator-activated inward current (IMI), which waxes and wanes periodically due to phasic feedback inhibition of MCN1 transmitter release. Each buildup of IMI enables the LG neuron to generate a self-terminating burst and thereby alternate with Int1 activity. Here we establish that CabPK drives gastric mill rhythm generation by activating in the LG neuron IMI plus a slowly activating transient, low-threshold inward current (ITrans-LTS) that is voltage, time, and Ca2+ dependent. Unlike MCN1, CabPK maintains a steady IMI activation, causing a subthreshold depolarization in LG that facilitates a periodic postinhibitory rebound burst caused by the regular buildup and decay of the availability of ITrans-LTS. Thus, different modulatory inputs can use different rhythm-generating mechanisms to drive the same neuronal rhythm. Additionally, the same ionic current (IMI) can play different roles under these different conditions, while different currents (IMI, ITrans-LTS) can play the same role. PMID:24227716

  14. Alpha-amylase circadian rhythm of young rat parotid gland: an endogenous rhythm with maternal coordination.

    PubMed

    Bellavía, S L; Sanz, E G; Sereno, R; Vermouth, N T

    1992-01-01

    The circadian rhythm of alpha-amylase, E.C. 3.2.1.1. alpha-1,4-glucan-4-glucanohydrolase) in the parotid glands of 25-day-old rats were studied under different experimental designs (fasting, reversed photoperiod, constant lighting conditions and treatment with reserpine and alpha-methyl-p-tyrosine). The rhythm of fasted rats did not change. There were modifications in the rhythm of rats submitted to a reversed photoperiod or treated with reserpine or alpha-methyl-p-tyrosine. The rhythm was present, with changes in the acrophase, in parotids of rats kept during their gestation and postnatal life in constant light or dark. Results suggest that the circadian rhythm of alpha-amylase in parotid gland of young rats is endogenous, synchronized by the photoperiod, and with maternal coordination. PMID:1610312

  15. Electrocardiographic Abnormalities and QTc Interval in Patients Undergoing Hemodialysis

    PubMed Central

    Nie, Yuxin; Zou, Jianzhou; Liang, Yixiu; Shen, Bo; Liu, Zhonghua; Cao, Xuesen; Chen, Xiaohong; Ding, Xiaoqiang

    2016-01-01

    Background Sudden cardiac death is one of the primary causes of mortality in chronic hemodialysis (HD) patients. Prolonged QTc interval is associated with increased rate of sudden cardiac death. The aim of this article is to assess the abnormalities found in electrocardiograms (ECGs), and to explore factors that can influence the QTc interval. Methods A total of 141 conventional HD patients were enrolled in this study. ECG tests were conducted on each patient before a single dialysis session and 15 minutes before the end of dialysis session (at peak stress). Echocardiography tests were conducted before dialysis session began. Blood samples were drawn by phlebotomy immediately before and after the dialysis session. Results Before dialysis, 93.62% of the patients were in sinus rhythm, and approximately 65% of the patients showed a prolonged QTc interval (i.e., a QTc interval above 440 ms in males and above 460ms in females). A comparison of ECG parameters before dialysis and at peak stress showed increases in heart rate (77.45±11.92 vs. 80.38±14.65 bpm, p = 0.001) and QTc interval (460.05±24.53 ms vs. 470.93±24.92 ms, p<0.001). After dividing patients into two groups according to the QTc interval, lower pre-dialysis serum concentrations of potassium (K+), calcium (Ca2+), phosphorus, calcium* phosphorus (Ca*P), and higher concentrations of plasma brain natriuretic peptide (BNP) were found in the group with prolonged QTc intervals. Patients in this group also had a larger left atrial diameter (LAD) and a thicker interventricular septum, and they tended to be older than patients in the other group. Then patients were divided into two groups according to ΔQTc (ΔQTc = QTc peak-stress- QTc pre-HD). When analyzing the patients whose QTc intervals were longer at peak stress than before HD, we found that they had higher concentrations of Ca2+ and P5+ and lower concentrations of K+, ferritin, UA, and BNP. They were also more likely to be female. In addition, more cardiac

  16. Open heart surgery

    MedlinePlus

    ... Heart bypass surgery (coronary artery bypass graft - CABG) Heart transplant Heart valve surgery Hypoplastic left heart repair Minimally ... Heart bypass surgery Heart bypass surgery - minimally invasive Heart transplant Heart valve surgery Hypoplastic left heart syndrome Patent ...

  17. Heart Attack

    MedlinePlus

    ... attack treatment works best when it's given right after symptoms occur. Prompt treatment of a heart attack can help prevent or limit damage to the heart and prevent sudden death. Call 9-1-1 Right Away A heart ...

  18. Heart attack

    MedlinePlus

    ... infarction; Non-ST-elevation myocardial infarction; NSTEMI; CAD-heart attack; Coronary artery disease-heart attack ... made up of cholesterol and other cells. A heart attack may occur when: A tear in the ...

  19. Heart Block

    MedlinePlus

    ... Block Explore Heart Block What Is... Electrical System & EKG Results Types Causes Who Is at Risk Signs & ... heart block. Doctors use a test called an EKG (electrocardiogram) to help diagnose heart block. This test ...

  20. Heart Anatomy

    MedlinePlus

    ... Incredible Machine Bonus poster (PDF) The Human Heart Anatomy Blood The Conduction System The Coronary Arteries The ... of the Leg Vasculature of the Torso Heart anatomy illustrations and animations for grades K-6. Heart ...

  1. Pitx2 modulates a Tbx5-dependent gene regulatory network to maintain atrial rhythm.

    PubMed

    Nadadur, Rangarajan D; Broman, Michael T; Boukens, Bastiaan; Mazurek, Stefan R; Yang, Xinan; van den Boogaard, Malou; Bekeny, Jenna; Gadek, Margaret; Ward, Tarsha; Zhang, Min; Qiao, Yun; Martin, James F; Seidman, Christine E; Seidman, Jon; Christoffels, Vincent; Efimov, Igor R; McNally, Elizabeth M; Weber, Christopher R; Moskowitz, Ivan P

    2016-08-31

    Cardiac rhythm is extremely robust, generating 2 billion contraction cycles during the average human life span. Transcriptional control of cardiac rhythm is poorly understood. We found that removal of the transcription factor gene Tbx5 from the adult mouse caused primary spontaneous and sustained atrial fibrillation (AF). Atrial cardiomyocytes from the Tbx5-mutant mice exhibited action potential abnormalities, including spontaneous depolarizations, which were rescued by chelating free calcium. We identified a multitiered transcriptional network that linked seven previously defined AF risk loci: TBX5 directly activated PITX2, and TBX5 and PITX2 antagonistically regulated membrane effector genes Scn5a, Gja1, Ryr2, Dsp, and Atp2a2 In addition, reduced Tbx5 dose by adult-specific haploinsufficiency caused decreased target gene expression, myocardial automaticity, and AF inducibility, which were all rescued by Pitx2 haploinsufficiency in mice. These results defined a transcriptional architecture for atrial rhythm control organized as an incoherent feed-forward loop, driven by TBX5 and modulated by PITX2. TBX5/PITX2 interplay provides tight control of atrial rhythm effector gene expression, and perturbation of the co-regulated network caused AF susceptibility. This work provides a model for the molecular mechanisms underpinning the genetic implication of multiple AF genome-wide association studies loci and will contribute to future efforts to stratify patients for AF risk by genotype. PMID:27582060

  2. Microglia modulate respiratory rhythm generation and autoresuscitation.

    PubMed

    Lorea-Hernández, Jonathan-Julio; Morales, Teresa; Rivera-Angulo, Ana-Julia; Alcantara-Gonzalez, David; Peña-Ortega, Fernando

    2016-04-01

    Inflammation has been linked to the induction of apneas and Sudden Infant Death Syndrome, whereas proinflammatory mediators inhibit breathing when applied peripherally or directly into the CNS. Considering that peripheral inflammation can activate microglia in the CNS and that this cell type can directly release all proinflammatory mediators that modulate breathing, it is likely that microglia can modulate breathing generation. It might do so also in hypoxia, since microglia are sensitive to hypoxia, and peripheral proinflammatory conditions affect gasping generation and autoresuscitation. Here, we tested whether microglial activation or inhibition affected respiratory rhythm generation. By measuring breathing as well as the activity of the respiratory rhythm generator (the preBötzinger complex), we found that several microglial activators or inhibitors, applied intracisternally in vivo or in the recording bath in vitro, affect the generation of the respiratory rhythms both in normoxia and hypoxia. Furthermore, microglial activation with lipopolysaccharide affected the ability of the animals to autoresuscitate after hypoxic conditions, an effect that is blocked when lipopolysaccharide is co-applied with the microglial inhibitor minocycline. Moreover, we found that the modulation of respiratory rhythm generation induced in vitro by microglial inhibitors was reproduced by microglial depletion. In conclusion, our data show that microglia can modulate respiratory rhythm generation and autoresuscitation. PMID:26678570

  3. Daily Rhythms in Mobile Telephone Communication.

    PubMed

    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. PMID:26390215

  4. Daily Rhythms in Mobile Telephone Communication

    PubMed Central

    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. PMID:26390215

  5. Mu rhythm desynchronization by tongue thrust observation

    PubMed Central

    Sakihara, Kotoe; Inagaki, Masumi

    2015-01-01

    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 (EEG) 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. PMID:26441599

  6. Heart attack

    MedlinePlus

    ... a heart attack take part in a cardiac rehabilitation program. ... al. eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, PA: Elsevier Saunders; 2014: ...

  7. Circadian Rhythm Disruption Was Observed in Hand, Foot, and Mouth Disease Patients

    PubMed Central

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

    2015-01-01

    Abstract 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 < 0.01) of temperature and respiratory rate were significantly different among 3 groups. But no statistical difference of amplitude in temperature and respiratory rate was observed among the 3 groups (P = 0.14). MESOR value of HR (P < 0.001) was significantly different in 3 groups. However, amplitude and acrophase revealed no statistical difference in 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

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

    PubMed

    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 < 0.01) of temperature and respiratory rate were significantly different among 3 groups. But no statistical difference of amplitude in temperature and respiratory rate was observed among the 3 groups (P = 0.14). MESOR value of HR (P < 0.001) was significantly different in 3 groups. However, amplitude and acrophase revealed no statistical difference in 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

  9. Genetic Basis of Human Circadian Rhythm Disorders

    PubMed Central

    Jones, Christopher R.; Huang, Angela L.; Ptáček, Louis J.; Fu, Ying-Hui

    2012-01-01

    Circadian rhythm disorders constitute a group of phenotypes that usually present as altered sleep-wake schedules. Until a human genetics approach was applied to investigate these traits, the genetic components regulating human circadian rhythm and sleep behaviors remained mysterious. Steady advances in the last decade have dramatically improved our understanding of the genes involved in circadian rhythmicity and sleep regulation. Finding these genes presents new opportunities to use a wide range of approaches, including in vitro molecular studies and in vivo animal modeling, to elevate our understanding of how sleep and circadian rhythms are regulated and maintained. Ultimately, this knowledge will reveal how circadian and sleep disruption contribute to various ailments and shed light on how best to maintain and recover good health. PMID:22849821

  10. Adjustment of sleep and the circadian temperature rhythm after flights across nine time zones

    NASA Technical Reports Server (NTRS)

    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.

  11. Congenital Heart Disease: Causes, Diagnosis, Symptoms, and Treatments.

    PubMed

    Sun, RongRong; Liu, Min; Lu, Lei; Zheng, Yi; Zhang, Peiying

    2015-07-01

    The congenital heart disease includes abnormalities in heart structure that occur before birth. Such defects occur in the fetus while it is developing in the uterus during pregnancy. About 500,000 adults have congenital heart disease in USA (WebMD, Congenital heart defects medications, www.WebMD.com/heart-disease/tc/congenital-heart-defects-medications , 2014). 1 in every 100 children has defects in their heart due to genetic or chromosomal abnormalities, such as Down syndrome. The excessive alcohol consumption during pregnancy and use of medications, maternal viral infection, such as Rubella virus, measles (German), in the first trimester of pregnancy, all these are risk factors for congenital heart disease in children, and the risk increases if parent or sibling has a congenital heart defect. These are heart valves defects, atrial and ventricular septa defects, stenosis, the heart muscle abnormalities, and a hole inside wall of the heart which causes defect in blood circulation, heart failure, and eventual death. There are no particular symptoms of congenital heart disease, but shortness of breath and limited ability to do exercise, fatigue, abnormal sound of heart as heart murmur, which is diagnosed by a physician while listening to the heart beats. The echocardiogram or transesophageal echocardiogram, electrocardiogram, chest X-ray, cardiac catheterization, and MRI methods are used to detect congenital heart disease. Several medications are given depending on the severity of this disease, and catheter method and surgery are required for serious cases to repair heart valves or heart transplantation as in endocarditis. For genetic study, first DNA is extracted from blood followed by DNA sequence analysis and any defect in nucleotide sequence of DNA is determined. For congenital heart disease, genes in chromosome 1 show some defects in nucleotide sequence. In this review the causes, diagnosis, symptoms, and treatments of congenital heart disease are described

  12. Heart Failure in Adult Congenital Heart Disease: Nonpharmacologic Treatment Strategies.

    PubMed

    LeMond, Lisa; Mai, Tuan; Broberg, Craig S; Muralidaran, Ashok; Burchill, Luke J

    2015-11-01

    In early stages, heart failure (HF) in adult congenital heart disease (ACHD) remains an elusive diagnosis. Many ACHD patients seem well-compensated owing to chronic physical and psychological adaptations. HF biomarkers and cardiopulmonary exercise tests are often markedly abnormal, although patients report stable health and good quality of life. Treatment differs from acquired HF. Evidence for effective drug therapy in ACHD-related HF is lacking. Residual ventricular, valvular, and vascular abnormalities contribute to HF pathophysiology, leading to an emphasis on nonpharmacologic treatment strategies. This article reviews emerging perspectives on nonpharmacologic treatment strategies, including catheter-based interventions, surgical correction, and palliative care. PMID:26471822

  13. Tooth - abnormal shape

    MedlinePlus

    Hutchinson incisors; Abnormal tooth shape; Peg teeth; Mulberry teeth; Conical teeth ... The appearance of normal teeth varies, especially the molars. ... conditions. Specific diseases can affect tooth shape, tooth ...

  14. Tooth - abnormal shape

    MedlinePlus

    Hutchinson incisors; Abnormal tooth shape; Peg teeth; Mulberry teeth; Conical teeth ... from many different conditions. Specific diseases can affect tooth shape, tooth color, time of appearance, or absence ...

  15. Heart Attack

    MedlinePlus

    ... have a heart attack. About half of them die. Many people have permanent heart damage or die because they don't get help immediately. It's ... few hours causes the affected heart muscle to die. NIH: National Heart, Lung, and Blood Institute

  16. Heart Transplantation

    MedlinePlus

    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 ...

  17. Heart Diseases

    MedlinePlus

    ... 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 ...

  18. Heart Diseases

    MedlinePlus

    ... re like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the U.S. ... disability. There are many different forms of heart disease. The most common cause of heart disease is ...

  19. Circadian rhythms and mood: Opportunities for multi-level analyses in genomics and neuroscience

    PubMed Central

    Li, Jun Z

    2014-01-01

    In the healthy state, both circadian rhythm and mood are stable against perturbations, yet they are capable of adjusting to altered internal cues or ongoing changes in external conditions. The dual demands of stability and flexibility are met by the collective properties of complex neural networks. Disruption of this balance underlies both circadian rhythm abnormality and mood disorders. However, we do not fully understand the network properties that govern the crosstalk between the circadian system and mood regulation. This puzzle reflects a challenge at the center of neurobiology, and its solution requires the successful integration of existing data across all levels of neural organization, from molecules, cells, circuits, network dynamics, to integrated mental function. This essay discusses several open questions confronting the cross-level synthesis, and proposes that circadian regulation, and its role in mood, stands as a uniquely tractable system to study the causal mechanisms of neural adaptation. PMID:24853393

  20. Magnetic resonance imaging of congenital heart disease

    SciTech Connect

    Fletcher, B.D.; Jacobstein, M.D.

    1988-01-01

    Focusing primarily on MR imaging of the heart, this book covers other diagnostic imaging modalities as well. The authors review new technologies and diagnostic procedures pertinent to congenital heat disease and present each congenital heat abnormality as a separate entity.

  1. Monkey Lipsmacking Develops Like the Human Speech Rhythm

    ERIC Educational Resources Information Center

    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…

  2. Perceptual Tests of Rhythmic Similarity: I. Mora Rhythm

    ERIC Educational Resources Information Center

    Murty, Lalita; Otake, Takashi; Cutler, Anne

    2007-01-01

    Listeners rely on native-language rhythm in segmenting speech; in different languages, stress-, syllable- or mora-based rhythm is exploited. The rhythmic similarity hypothesis holds that where two languages have similar rhythm, listeners of each language should segment their own and the other language similarly. Such similarity in listening was…

  3. The Features and Training of English Stress and Rhythm

    ERIC Educational Resources Information Center

    Cai, Cui-yun

    2008-01-01

    In second language learning, to possess a perfect pronunciation, the importance of stress and rhythm should not be ignored. This articles explores the nature of sentence and word stress as well as rhythm, thus putting forward some feasible ways of training and acquiring a good English stress and rhythm in EFLT (English as Foreign Language…

  4. Does Melody Assist in the Reproduction of Novel Rhythm Patterns?

    ERIC Educational Resources Information Center

    Kinney, Daryl W.; Forsythe, Jere L.

    2013-01-01

    We examined music education majors' ability to reproduce rhythmic stimuli presented in melody and rhythm only conditions. Participants reproduced rhythms of two-measure music examples by immediately echo-performing through a method of their choosing (e.g., clapping, tapping, vocalizing). Forty examples were presented in melody and rhythm only…

  5. Structurally abnormal human autosomes

    SciTech Connect

    1993-12-31

    Chapter 25, discusses structurally abnormal human autosomes. This discussion includes: structurally abnormal chromosomes, chromosomal polymorphisms, pericentric inversions, paracentric inversions, deletions or partial monosomies, cri du chat (cat cry) syndrome, ring chromosomes, insertions, duplication or pure partial trisomy and mosaicism. 71 refs., 8 figs.

  6. The Rhythm of Perception: Entrainment to Acoustic Rhythms Induces Subsequent Perceptual Oscillation.

    PubMed

    Hickok, Gregory; Farahbod, Haleh; Saberi, Kourosh

    2015-07-01

    Acoustic rhythms are pervasive in speech, music, and environmental sounds. Recent evidence for neural codes representing periodic information suggests that they may be a neural basis for the ability to detect rhythm. Further, rhythmic information has been found to modulate auditory-system excitability, which provides a potential mechanism for parsing the acoustic stream. Here, we explored the effects of a rhythmic stimulus on subsequent auditory perception. We found that a low-frequency (3 Hz), amplitude-modulated signal induces a subsequent oscillation of the perceptual detectability of a brief nonperiodic acoustic stimulus (1-kHz tone); the frequency but not the phase of the perceptual oscillation matches the entrained stimulus-driven rhythmic oscillation. This provides evidence that rhythmic contexts have a direct influence on subsequent auditory perception of discrete acoustic events. Rhythm coding is likely a fundamental feature of auditory-system design that predates the development of explicit human enjoyment of rhythm in music or poetry. PMID:25968248

  7. The rhythm of retinoids in the brain

    PubMed Central

    Ransom, Jemma; Morgan, Peter J; McCaffery, Peter J; Stoney, Patrick N

    2014-01-01

    The retinoids are a family of compounds that in nature are derived from vitamin A or pro-vitamin A carotenoids. An essential part of the diet for mammals, vitamin A has long been known to be essential for many organ systems in the adult. More recently, however, they have been shown to be necessary for function of the brain and new discoveries point to a central role in processes ranging from neuroplasticity to neurogenesis. Acting in several regions of the central nervous system including the eye, hippocampus and hypothalamus, one common factor in its action is control of biological rhythms. This review summarizes the role of vitamin A in the brain; its action through the metabolite retinoic acid via specific nuclear receptors, and the regulation of its concentration through controlled synthesis and catabolism. The action of retinoic acid to regulate several rhythms in the brain and body, from circadian to seasonal, is then discussed to finish with the importance of retinoic acid in the regular pattern of sleep. We review the role of vitamin A and retinoic acid (RA) as mediators of rhythm in the brain. In the suprachiasmatic nucleus and hippocampus they control expression of circadian clock genes while in the cortex retinoic acid is required for delta oscillations of sleep. Retinoic acid is also central to a second rhythm that keeps pace with the seasons, regulating function in the hypothalamus and pineal gland. PMID:24266881

  8. Characterization of neurospora circadian rhythms in space

    NASA Technical Reports Server (NTRS)

    Ferraro, James S.

    1987-01-01

    To determine whether the circadian rhythm of conidiation in neurospora crassa is endogenously derived or is driven by some geophysical time cue, an experiment was conducted on space shuttle flight STS-9, where inoculated race tubes were exposed to the microgravity environment of space. The results demonstated that the rhythm can persist in space. However, there were several minor alterations noted; an increase in the period of the oscillation and the variability of the growth rate and a diminished rhythm amplitude, which eventually damped out in 25% of the flight tubes. On day seven of the flight, the tubes were exposed to light while their growth fronts were marked. It appears that some aspects of this marking process reinstated a robust rhythm in all the tubes which continued throughout the remainder of the flight. It was hypothesized that the damping found prior to the marking procedure on STS-9 may have been a result of the hypergravity pulse of launch and not due to the microgravity of the orbital lab; furthermore, that the marking procedure, by exposing the samples to light, had reinstated rhythmicity. To test this, an investigation was conducted into the effects of acute and chronic exposure to hypergravity.

  9. Neuroscience: A Sleep Rhythm with Multiple Facets.

    PubMed

    Koo, Ping Chai; Marshall, Lisa

    2016-09-12

    Sleep spindles were one of the first rhythms associated with learning and memory consolidation. Current research shows spindles can reflect features of trait and time-varying properties of neuroplasticity. A new study has now used feedback-controlled spindle frequency stimulation to show that sleep spindles modulate endogenous brain electric activity and behavior. PMID:27623266

  10. Environmental synchronizers of squirrel monkey circadian rhythms

    NASA Technical Reports Server (NTRS)

    Sulzman, F. M.; Fuller, C. A.; Moore-Ede, M. C.

    1977-01-01

    Various temporal signals in the environment were tested to determine if they could synchronize the circadian timing system of the squirrel monkey (Saimiri sciureus). The influence of cycles of light and dark, eating and fasting, water availability and deprivation, warm and cool temperature, sound and quiet, and social interaction and isolation on the drinking and activity rhythms of unrestrained monkeys was examined. In the absence of other time cues, 24-hr cycles of each of these potential synchronizers were applied for up to 3 wk, and the periods of the monkey's circadian rhythms were examined. Only light-dark cycles and cycles of food availability were shown to be entraining agents, since they were effective in determining the period and phase of the rhythmic variables. In the presence of each of the other environmental cycles, the monkey's circadian rhythms exhibited free-running periods which were significantly different from 24 hr with all possible phase relationships between the rhythms and the environmental cycles being examined.

  11. Circadian temperature rhythms of older people

    NASA Technical Reports Server (NTRS)

    Monk, T. H.; Buysse, D. J.; Reynolds, C. F. 3rd; Kupfer, D. J.; Houck, P. R.

    1995-01-01

    This collection of studies had the aim of exploring whether older (77+ years) men and women have circadian body temperature rhythms different from those of younger adults. A total of 20 older men and 28 older women were compared with either 22 young men or 14 middle-aged men in four protocols; all but the first protocol using a subset of the sample. The four protocols were: 1) 24 h, and 2) 72 h data collections on a normal laboratory routine (sleeping at night); 3) between 36 h and 153 h of field data collection at home; and 4) 36 h of a constant conditions routine (wakeful bedrest under temporal isolation) in the laboratory. There was some evidence for an age-related phase advance in temperature rhythm, especially for the older men on a normal routine, though this was not present in the constant conditions protocol, where 5 of the older subjects showed major delays in the timing of the body temperature trough (10:00 or later). There was no statistically significant evidence from any of the protocols that older subjects generally had lower temperature rhythm amplitudes than younger adults. Only when older men were compared with younger men in 24-h rhythm amplitude by simple t-test did any comparison involving amplitude achieve statistical significance (p < 0.05).

  12. Procedures for numerical analysis of circadian rhythms

    PubMed Central

    REFINETTI, ROBERTO; LISSEN, GERMAINE CORNÉ; HALBERG, FRANZ

    2010-01-01

    This article reviews various procedures used in the analysis of circadian rhythms at the populational, organismal, cellular and molecular levels. The procedures range from visual inspection of time plots and actograms to several mathematical methods of time series analysis. Computational steps are described in some detail, and additional bibliographic resources and computer programs are listed. PMID:23710111

  13. Emotion and Rhythm in Critical Learning Incidents

    ERIC Educational Resources Information Center

    Soini, Hannu; Flynn, Mark

    2005-01-01

    In this paper, we analyzed the descriptions of learning provided by 234 College of Education students from Finland and Canada and compared them with Whitehead's (1932/1962) epistemological theory of the rhythm of mental growth. The students were asked to "Give a concrete example of a situation in which you really learned something." The…

  14. [Circadian rhythm sleep disorders in psychiatric diseases].

    PubMed

    Bromundt, Vivien

    2014-11-01

    Circadian rhythm sleep disorders are prevalent among psychiatric patients. This is most probable due to a close relationship between functional disturbances of the internal clock, sleep regulation and mental health. Mechanisms on molecular level of the circadian clock and neurotransmitter signalling are involved in the development of both disorders. Moreover, circadian disorders and psychiatric diseases favour each other by accessory symptoms such as stress or social isolation. Actimetry to objectively quantify the rest-activity cycle and salivary melatonin profiles as marker for the circadian phase help to diagnose circadian rhythm sleep disorders in psychiatric patients. Chronotherapeutics such as bright light therapy, dark therapy, melatonin administration, and wake therapy are used to synchronise and consolidate circadian rhythms and help in the treatment of depression and other psychiatric disorders, but are still neglected in medicine. More molecular to behavioural research is needed for the understanding of the development of circadian disorders and their relationship to psychiatric illnesses. This will help to boost the awareness and treatment of circadian rhythm sleep disorders in psychiatry. PMID:25377290

  15. Circadian rhythm of gravitaxis in Euglena gracilis.

    PubMed

    Lebert, M; Porst, M; Hader, D P

    1999-09-01

    Euglena gracilis, a unicellular, photosynthetic flagellate is a model system for environmentally controlled behavioral reactions. One pronounced reaction is the orientation with respect to gravity. In synchronized cultures with no cell growth a distinct circadian rhythm of negative gravitactic orientation could be observed. The main maximum of sensitivity was detected 5 h after the beginning of the subjective day, the main minimum 5 h before the beginning of the subjective day. Transferring synchronized cultures to continuous light resulted in an almost instantaneous loss of rhythmicity. In contrast, after transfer to permanent darkness cells exhibited a circadian rhythm with a progressive shortening of the period for more than 5 days. These findings are in contrast to the circadian rhythm of phototaxis in Euglena, where a free-running period of 24 h was observed. Parallel measurements of negative gravitactic orientation, velocity, cell shape as well as cAMP concentration in synchronized cultures revealed a circadian rhythm of all reactions. The results are discussed with regard to the possible role of cell shape and cAMP in gravitactic orientation. PMID:11542916

  16. Human autonomic rhythms: vagal cardiac mechanisms in tetraplegic subjects

    NASA Technical Reports Server (NTRS)

    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

  17. A timely review of state-of-the-art chronopharmaceuticals synchronized with biological rhythms.

    PubMed

    Sewlall, Seshni; Pillay, Viness; Danckwerts, Michael P; Choonara, Yahya E; Ndesendo, Valence M K; du Toit, Lisa C

    2010-12-01

    Extensive research into circadian rhythms and their influence on biological systems has given rise to the science of chronobiology and subsequently chronotherapy, the science of delivering drugs in synchrony with biological rhythms. The field of chronotherapeutics paves the way for advances and complexities in current drug delivery technology. The ultimate goal of current chronopharmaceutical research strives to design ideal chronotherapeutic drug delivery systems that respond to such therapeutic needs. Considering the fact that physiological events such as heart rate, blood pressure, plasma concentration of hormones, plasma proteins and enzymes display constancy over time, drug delivery systems with constant release profiles have thus been favored. However, due to circadian rhythms, the conventional paradigm of constant drug delivery may not be what is needed. Instead, precisely timed drug delivery systems are required in order to correlate drug delivery with circadian rhythms to provide maximum therapeutic efficacy for chronotherapeutic diseases when most needed. The aim of this review paper is to outline the concepts in designing chronopharmaceuticals from a clinical viewpoint of major chronotherapeutic diseases such as asthma, allergic rhinitis, cardiovascular disorders, rheumatoid arthritis and cancer as well as relatively minor niche areas of interest such as in glaucoma, diabetes, immunity, pain, gastric ulcers, epilepsy and even HIV/AIDS that would require chronotherapy. In addition this review paper attempts to concisely assimilate and explicate the role of circadian rhythms in these various disease states and provide a focused overview of the current state-of-the-art in designing strategies for chronopharmaceutical formulations employed for treating chronotherapeutic diseases. PMID:20950265

  18. Wheel running improves REM sleep and attenuates stress-induced flattening of diurnal rhythms in F344 rats.

    PubMed

    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. PMID:27124542

  19. Cardiorespiratory Coupling: Common Rhythms in Cardiac, Sympathetic, and Respiratory Activities

    PubMed Central

    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

  20. From Biological Rhythms to Social Rhythms: Physiological Precursors of Mother-Infant Synchrony

    ERIC Educational Resources Information Center

    Feldman, Ruth

    2006-01-01

    Links between neonatal biological rhythms and the emergence of interaction rhythms were examined in 3 groups (N=71): high-risk preterms (HR; birth weight less than 1,000 g), low-risk preterms (LR; birth weight=1,700-1,850 g), and full-term (FT) infants. Once a week for premature infants and on the 2nd day for FT infants, sleep-wake cyclicity was…

  1. Influence of head-down bed rest on the circadian rhythms of hormones and electrolytes involved in hydroelectrolytic regulation

    NASA Technical Reports Server (NTRS)

    Millet, C.; Custaud, M. A.; Allevard, A. M.; Zaouali-Ajina, M.; Monk, T. H.; Arnaud, S. B.; Claustrat, B.; Gharib, C.; Gauquelin-Koch, G.

    2001-01-01

    We investigated in six men the impact of a 17-day head-down bed rest (HDBR) on the circadian rhythms of the hormones and electrolytes involved in hydroelectrolytic regulation. This HDBR study was designed to mimic an actual spaceflight. Urine samples were collected at each voiding before, during and after HDBR. Urinary excretion of aldosterone, arginine vasopressin (AVP), cyclic guanosine monophosphate (cGMP), cortisol, electrolytes (Na+ and K+) and creatinine were determined. HDBR resulted in a significant reduction of body mass (P < 0.01) and of caloric intake [mean (SEM) 2,778 (37) kcal.24 h(-1) to 2,450 (36) kcal.24 h(-1), where 1 kcal.h(-1) = 1.163 J.s(-1); P< 0.01]. There was a significant increase in diastolic blood pressure [71.8 (0.7) mmHg vs 75.6 (0.91) mmHg], with no significant changes in either systolic blood pressure or heart rate. The nocturnal hormonal decrease of aldosterone was clearly evident only before and after HDBR, but the day/night difference did not appear during HDBR. The rhythm of K+ excretion was unchanged during HDBR, whereas for Na+ excretion, a large decrease was shown during the night as compared to the day. The circadian rhythm of cortisol persisted. These data suggest that exposure to a 17-day HDBR could induce an exaggeration of the amplitude of the Na+ rhythm and abolition of the aldosterone rhythm.

  2. Characterisation of circadian rhythms of various duckweeds.

    PubMed

    Muranaka, T; Okada, M; Yomo, J; Kubota, S; Oyama, T

    2015-01-01

    The plant circadian clock controls various physiological phenomena that are important for adaptation to natural day-night cycles. Many components of the circadian clock have been identified in Arabidopsis thaliana, the model plant for molecular genetic studies. Recent studies revealed evolutionary conservation of clock components in green plants. Homologues of clock-related genes have been isolated from Lemna gibba and Lemna aequinoctialis, and it has been demonstrated that these homologues function in the clock system in a manner similar to their functioning in Arabidopsis. While clock components are widely conserved, circadian phenomena display diversity even within the Lemna genus. In order to survey the full extent of diversity in circadian rhythms among duckweed plants, we characterised the circadian rhythms of duckweed by employing a semi-transient bioluminescent reporter system. Using a particle bombardment method, circadian bioluminescent reporters were introduced into nine strains representing five duckweed species: Spirodela polyrhiza, Landoltia punctata, Lemna gibba, L. aequinoctialis and Wolffia columbiana. We then monitored luciferase (luc+) reporter activities driven by AtCCA1, ZmUBQ1 or CaMV35S promoters under entrainment and free-running conditions. Under entrainment, AtCCA1::luc+ showed similar diurnal rhythms in all strains. This suggests that the mechanism of biological timing under day-night cycles is conserved throughout the evolution of duckweeds. Under free-running conditions, we observed circadian rhythms of AtCCA1::luc+, ZmUBQ1::luc+ and CaMV35S::luc+. These circadian rhythms showed diversity in period length and sustainability, suggesting that circadian clock mechanisms are somewhat diversified among duckweeds. PMID:24942699

  3. Biologic rhythms derived from Siberian mammoths' hairs.

    PubMed

    Spilde, Mike; Lanzirotti, Antonio; Qualls, Clifford; Phillips, Genevieve; Ali, Abdul-Mehdi; Agenbroad, Larry; Appenzeller, Otto

    2011-01-01

    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. PMID:21747920

  4. Biologic Rhythms Derived from Siberian Mammoths' Hairs

    PubMed Central

    Spilde, Mike; Lanzirotti, Antonio; Qualls, Clifford; Phillips, Genevieve; Ali, Abdul-Mehdi; Agenbroad, Larry; Appenzeller, Otto

    2011-01-01

    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. PMID:21747920

  5. Biologic Rhythms Derived from Siberian Mammoths Hairs

    SciTech Connect

    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.

  6. The Validity and Reliability of Rhythm Measurements in Automatically Scoring the English Rhythm Proficiency of Chinese EFL Learners

    ERIC Educational Resources Information Center

    Chen, Jin; Lin, Jianghao; Li, Xinguang

    2015-01-01

    This article aims to find out the validity of rhythm measurements to capture the rhythmic features of Chinese English. Besides, the reliability of the valid rhythm measurements applied in automatically scoring the English rhythm proficiency of Chinese EFL learners is also explored. Thus, two experiments were carried out. First, thirty students of…

  7. A prototype-based resonance model of rhythm categorization

    PubMed Central

    Bååth, Rasmus; Lagerstedt, Erik; Gärdenfors, Peter

    2014-01-01

    Categorization of rhythmic patterns is prevalent in musical practice, an example of this being the transcription of (possibly not strictly metrical) music into musical notation. In this article we implement a dynamical systems' model of rhythm categorization based on the resonance theory of rhythm perception developed by Large (2010). This model is used to simulate the categorical choices of participants in two experiments of Desain and Honing (2003). The model accurately replicates the experimental data. Our results support resonance theory as a viable model of rhythm perception and show that by viewing rhythm perception as a dynamical system it is possible to model central properties of rhythm categorization. PMID:26034564

  8. Implantation of Total Artificial Heart in Congenital Heart Disease

    PubMed Central

    Adachi, Iki; Morales, David S. L.

    2014-01-01

    In patients with end-stage heart failure (HF), a total artificial heart (TAH) may be implanted as a bridge to cardiac transplant. However, in congenital heart disease (CHD), the malformed heart presents a challenge to TAH implantation. In the case presented here, a 17 year-old patient with congenital transposition of the great arteries (CCTGA) experienced progressively worsening HF due to his congenital condition. He was hospitalized multiple times and received an implantable cardioverter defibrillator (ICD). However, his condition soon deteriorated to end-stage HF with multisystem organ failure. Due to the patient's grave clinical condition and the presence of complex cardiac lesions, the decision was made to proceed with a TAH. The abnormal arrangement of the patient's ventricles and great arteries required modifications to the TAH during implantation. With the TAH in place, the patient was able to return home and regain strength and physical well-being while awaiting a donor heart. He was successfully bridged to heart transplantation 5 months after receiving the device. This report highlights the TAH is feasible even in patients with structurally abnormal hearts, with technical modification. PMID:25078059

  9. Modeling heart rate variability by stochastic feedback

    NASA Technical Reports Server (NTRS)

    Amaral, L. A.; Goldberger, A. L.; Stanley, H. E.

    1999-01-01

    We consider the question of how the cardiac rhythm spontaneously self-regulates and propose a new mechanism as a possible answer. We model the neuroautonomic regulation of the heart rate as a stochastic feedback system and find that the model successfully accounts for key characteristics of cardiac variability, including the 1/f power spectrum, the functional form and scaling of the distribution of variations of the interbeat intervals, and the correlations in the Fourier phases which indicate nonlinear dynamics.

  10. Rhythm measures and dimensions of durational variation in speech.

    PubMed

    Loukina, Anastassia; Kochanski, Greg; Rosner, Burton; Keane, Elinor; Shih, Chilin

    2011-05-01

    Patterns of durational variation were examined by applying 15 previously published rhythm measures to a large corpus of speech from five languages. In order to achieve consistent segmentation across all languages, an automatic speech recognition system was developed to divide the waveforms into consonantal and vocalic regions. The resulting duration measurements rest strictly on acoustic criteria. Machine classification showed that rhythm measures could separate languages at rates above chance. Within-language variability in rhythm measures, however, was large and comparable to that between languages. Therefore, different languages could not be identified reliably from single paragraphs. In experiments separating pairs of languages, a rhythm measure that was relatively successful at separating one pair often performed very poorly on another pair: there was no broadly successful rhythm measure. Separation of all five languages at once required a combination of three rhythm measures. Many triplets were about equally effective, but the confusion patterns between languages varied with the choice of rhythm measures. PMID:21568427

  11. [Interpersonal and social rhythm therapy (IPSRT)].

    PubMed

    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

  12. Impairment of beat-based rhythm discrimination in Parkinson's disease.

    PubMed

    Grahn, Jessica A; Brett, Matthew

    2009-01-01

    Humans often synchronize movements to the beat, indicating that motor areas may be involved in detecting or generating a beat. The basal ganglia have been shown to be preferentially activated by perception of rhythms with a regular beat (Grahn and Brett, 2007), but their necessity for beat-based rhythm processing has not been proven. Previous research has shown that Parkinson's disease (PD) patients are impaired in timing of isochronous intervals (Harrington et al., 1998a; O'Boyle et al., 1996), but little work has tested more complex rhythms. In healthy volunteers, behavioural performance is better for rhythms with a beat than without a beat (Essens, 1986). We tested PD patients and controls on a rhythm discrimination task to determine if basal ganglia dysfunction results in an impairment of processing rhythms that have a beat. Unlike rhythm reproduction, discrimination has no motor requirements that are problematic for patients. Half the rhythms had a beat-based structure, and half did not. Subjects heard a rhythm twice and then indicated if a third presentation of the rhythm was the same or different. We predicted that PD patients would benefit less from beat structure than controls, resulting in a group by rhythm-type interaction, with reduced relative performance for the beat-based sequences in the PD group. Indeed this was the pattern of the results. In the control group, a significant advantage was observed for discrimination of rhythms with a beat compared to those without a beat. This advantage was greatly reduced in the PD group. Discrimination of beat-based rhythms was significantly impaired in PD patients compared to controls, whereas discrimination of non-beat-based rhythms did not differ significantly. This suggests that the basal ganglia are part of a system involved in detecting or generating an internal beat, and that this system is compromised in patients with Parkinson's disease. PMID:19027895

  13. "Jeopardy" in Abnormal Psychology.

    ERIC Educational Resources Information Center

    Keutzer, Carolin S.

    1993-01-01

    Describes the use of the board game, Jeopardy, in a college level abnormal psychology course. Finds increased student interaction and improved application of information. Reports generally favorable student evaluation of the technique. (CFR)

  14. Abnormal Uterine Bleeding

    MedlinePlus

    ... Abnormal uterine bleeding is any bleeding from the uterus (through your vagina) other than your normal monthly ... or fibroids (small and large growths) in the uterus can also cause bleeding. Rarely, a thyroid problem, ...

  15. Abnormal Uterine Bleeding FAQ

    MedlinePlus

    ... as cancer of the uterus, cervix, or vagina • Polycystic ovary syndrome How is abnormal bleeding diagnosed? Your health care ... before the fetus can survive outside the uterus. Polycystic Ovary Syndrome: A condition characterized by two of the following ...

  16. Successful orthotopic heart transplantation using a donor heart with ALCAPA.

    PubMed

    Simmonds, J D; Mustafa, M; Fajardo Jaramillo, D P; Bellsham-Revell, H R; Marek, J; Burch, M; Tsang, V T; Muthialu, N

    2016-09-01

    With the imbalance between donation rates and potential recipients growing, transplant programs are increasingly using non-ideal organs from so-called marginal donors. This is the first reported case of the intentional use of a donor heart with ALCAPA. The recipient was aged one yr with restrictive cardiomyopathy who had been supported with BiVAD for over six months. Function of the donor left ventricle was shown to be well preserved, with no obvious signs of ischemia, except for a fibrotic layer on the anterolateral papillary muscle of the mitral valve. To prevent coronary steal, the anomalous left coronary artery ostium from the MPA was oversewn prior to implantation. The transplanted heart spontaneously regained sinus rhythm immediately following cross-clamp release and showed good contractility from the first postoperative echocardiogram. The patient continues to do well 18 months post-transplant, with excellent function on echocardiography, and good flow on coronary angiography. PMID:27384867

  17. Heart pacemaker

    MedlinePlus

    ... 1 ounce. Most pacemakers have 2 parts: The generator contains the battery and the information to control ... are wires that connect the heart to the generator and carry the electrical messages to the heart. ...

  18. Heart Health

    MedlinePlus

    ... nih.gov/Go4Life Heart Health Just like an engine makes a car go, your heart keeps your ... all at once —10-minute periods will do. Start by doing activities you enjoy—brisk walking, dancing, ...

  19. Heart Disease

    MedlinePlus

    ... with heart disease? What do my cholesterol and triglyceride numbers mean? How can I lower my cholesterol? ... weight Know your numbers (blood pressure, cholesterol, and triglycerides) You can reduce your chances of getting heart ...

  20. Heart Failure

    MedlinePlus

    ... arrhythmias) The use of toxic substances (such as alcohol or drug abuse) Congenital heart defect (a heart problem you were born with) Diabetes Thyroid problems Diagnosis & Tests How will my doctor know if I ...

  1. Heart Disease

    MedlinePlus

    ... this? Submit What's this? Submit Button Related CDC Web Sites Division for Heart Disease and Stroke Prevention ... this? Submit What's this? Submit Button Related CDC Web Sites Division for Heart Disease and Stroke Prevention ...

  2. Chromosomal Abnormalities and Schizophrenia

    PubMed Central

    BASSETT, ANNE S.; CHOW, EVA W.C.; WEKSBERG, ROSANNA

    2011-01-01

    Schizophrenia is a common and serious psychiatric illness with strong evidence for genetic causation, but no specific loci yet identified. Chromosomal abnormalities associated with schizophrenia may help to understand the genetic complexity of the illness. This paper reviews the evidence for associations between chromosomal abnormalities and schizophrenia and related disorders. The results indicate that 22q11.2 microdeletions detected by fluorescence in-situ hybridization (FISH) are significantly associated with schizophrenia. Sex chromosome abnormalities seem to be increased in schizophrenia but insufficient data are available to indicate whether schizophrenia or related disorders are increased in patients with sex chromosome aneuploidies. Other reports of chromosomal abnormalities associated with schizophrenia have the potential to be important adjuncts to linkage studies in gene localization. Advances in molecular cytogenetic techniques (i.e., FISH) have produced significant increases in rates of identified abnormalities in schizophrenia, particularly in patients with very early age at onset, learning difficulties or mental retardation, or dysmorphic features. The results emphasize the importance of considering behavioral phenotypes, including adult onset psychiatric illnesses, in genetic syndromes and the need for clinicians to actively consider identifying chromosomal abnormalities and genetic syndromes in selected psychiatric patients. PMID:10813803

  3. Heart Attack

    MedlinePlus

    ... a million people in the U.S. have a heart attack. About half of them die. Many people have permanent heart damage or die because they don't get ... It's important to know the symptoms of a heart attack and call 9-1-1 if someone ...

  4. Sleep, Circadian Rhythms, and Anxious Traits.

    PubMed

    Coles, Meredith E; Schubert, Jessica R; Nota, Jacob A

    2015-09-01

    Anxiety is adaptive and plays an important role in keeping us safe. However, when anxiety becomes too extreme, it can cause significant disruptions and distress. Understanding the mechanisms underlying excessive anxiety and how to best treat it is a priority for researchers and clinicians. There is increasing recognition that disruptions in the amount and timing of sleep are associated with anxiety symptoms and characteristics. In the current paper, we explore the intersections between sleep, circadian rhythms, and anxiety. First, we review accumulating evidence that anxiety is associated with disruptions in sleep and circadian rhythms in both clinical and nonclinical samples and across ages. Next, we discuss the data linking sleep disruptions with anxiety-related traits (anxiety sensitivity, neuroticism, and perfectionism) and patterns of cognition and emotion. Finally, potential treatment implications are highlighted. Overall, these data suggest that delineating the role of disruptions in the amount and timing of sleep holds promise for improving the lives of individuals with heightened anxiety. PMID:26216591

  5. Circadian rhythms: basic neurobiology and clinical applications.

    PubMed

    Moore, R Y

    1997-01-01

    Circadian rhythms are major features of adaptation to our environment. In mammals, circadian rhythms are generated and regulated by a circadian timing system. This system consists of entertainment pathways, pacemakers, and pace-maker output to effector systems that are under circadian control. The primary entertainment pathway is the retinohypothalamic tract, which terminates in the circadian pacemakers, the suprachiasmatic nuclei of the hypothalamus. The output of the suprachiasmatic nuclei is principally to the hypothalamus, the midline thalamus, and the basal forebrain. This provides a temporal organization to the sleep-wake cycle, to many physiological and endocrine functions, and to psychomotor performance functions. Disorders of circadian timing primarily affect entertainment and pacemaker functions. The pineal hormone, melatonin, appears to be promising agent for therapy of some circadian timing disorders. PMID:9046960

  6. [Molecular oscillatory machinery of circadian rhythms].

    PubMed

    Yamaguchi, Yoshiaki; Okamura, Hitoshi

    2012-07-01

    Many metabolic and physiological processes display daily rhythms oscillated by the internal circadian clock system. This rhythm is generated by interlocked transcription-(post) translation feedback loops of clock genes: the core oscillatory loop, being composed of CLOCK/BMAL1 heterodimer activating the expressions of PER and CRY that directly repress CLOCK/BMAL1, is accompanied by accessory loops consisted with REV-ERB nuclear receptor repressing Bmal1 or with DBP competing with E4BP4 on D-box site. These clock proteins are regulated by phosphorylation and ubiquitination (PER/CRY), and acetylation (CLOCK/BMAL1). Recently, a deacetylating protein SIRT1 mediated metabolic pathway is discovered to be interlocked with core oscillatory loop via Nampt expression, a late-limiting enzyme in NAD+ salvage pathway. Since many key-step enzymes of metabolisms are regulated by the circadian clock, circadian clock system may intimately link to cellular metabolism. PMID:22844791

  7. Circadian rhythms of performance: new trends

    NASA Technical Reports Server (NTRS)

    Carrier, J.; Monk, T. H.

    2000-01-01

    This brief review is concerned with how human performance efficiency changes as a function of time of day. It presents an overview of some of the research paradigms and conceptual models that have been used to investigate circadian performance rhythms. The influence of homeostatic and circadian processes on performance regulation is discussed. The review also briefly presents recent mathematical models of alertness that have been used to predict cognitive performance. Related topics such as interindividual differences and the postlunch dip are presented.

  8. Subjective alertness rhythms in elderly people

    NASA Technical Reports Server (NTRS)

    Monk, T. H.; Buysse, D. J.; Reynolds, C. F. 3rd; Kupfer, D. J.; Houck, P. R.

    1996-01-01

    The aim of this study was to evaluate age-related changes in the circadian rhythm of subjective alertness and to explore the circadian mechanisms underlying such changes. Using a visual analogue scale (VAS) instrument, 25 older men and women (71 y and older; 15 female, 10 male) rated their subjective alertness about 7 times per day during 5 baseline days of temporal isolation during which habitual bedtimes and waketimes were enforced. Comparisons were made with 13 middle-aged men (37-52 y) experiencing the same protocol. Advancing age (particularly in the men) resulted in less rhythmic alertness patterns, as indicated by lower amplitudes and less reliability of fitted 24-h sinusoids. This appeared in spite of the absence of any reliable age-related diminution in circadian temperature rhythm amplitude, thus suggesting the effect was not due to SCN weakness per se, but to weakened transduction of SCN output. In a further experiment, involving 36 h of constant wakeful bedrest, differences in the amplitude of the alertness rhythm were observed between 9 older men (79 y+), 7 older women (79 y+), and 17 young controls (9 males, 8 females, 19-28 y) suggesting that with advancing age (particularly in men) there is less rhythmic input into subjective alertness from the endogenous circadian pacemaker. These results may explain some of the nocturnal insomnia and daytime hypersomnia that afflict many elderly people.

  9. Respiratory modulation of human autonomic rhythms

    NASA Technical Reports Server (NTRS)

    Badra, L. J.; Cooke, W. H.; Hoag, J. B.; Crossman, A. A.; Kuusela, T. A.; Tahvanainen, K. U.; Eckberg, D. L.

    2001-01-01

    We studied the influence of three types of breathing [spontaneous, frequency controlled (0.25 Hz), and hyperventilation with 100% oxygen] and apnea on R-R interval, photoplethysmographic arterial pressure, and muscle sympathetic rhythms in nine healthy young adults. We integrated fast Fourier transform power spectra over low (0.05-0.15 Hz) and respiratory (0.15-0.3 Hz) frequencies; estimated vagal baroreceptor-cardiac reflex gain at low frequencies with cross-spectral techniques; and used partial coherence analysis to remove the influence of breathing from the R-R interval, systolic pressure, and muscle sympathetic nerve spectra. Coherence among signals varied as functions of both frequency and time. Partialization abolished the coherence among these signals at respiratory but not at low frequencies. The mode of breathing did not influence low-frequency oscillations, and they persisted during apnea. Our study documents the independence of low-frequency rhythms from respiratory activity and suggests that the close correlations that may exist among arterial pressures, R-R intervals, and muscle sympathetic nerve activity at respiratory frequencies result from the influence of respiration on these measures rather than from arterial baroreflex physiology. Most importantly, our results indicate that correlations among autonomic and hemodynamic rhythms vary over time and frequency, and, thus, are facultative rather than fixed.

  10. Detecting Rhythms in Time Series with RAIN

    PubMed Central

    Thaben, Paul F.; Westermark, Pål O.

    2014-01-01

    A fundamental problem in research on biological rhythms is that of detecting and assessing the significance of rhythms in large sets of data. Classic methods based on Fourier theory are often hampered by the complex and unpredictable characteristics of experimental and biological noise. Robust nonparametric methods are available but are limited to specific wave forms. We present RAIN, a robust nonparametric method for the detection of rhythms of prespecified periods in biological data that can detect arbitrary wave forms. When applied to measurements of the circadian transcriptome and proteome of mouse liver, the sets of transcripts and proteins with rhythmic abundances were significantly expanded due to the increased detection power, when we controlled for false discovery. Validation against independent data confirmed the quality of these results. The large expansion of the circadian mouse liver transcriptomes and proteomes reflected the prevalence of nonsymmetric wave forms and led to new conclusions about function. RAIN was implemented as a freely available software package for R/Bioconductor and is presently also available as a web interface. PMID:25326247

  11. Chronotypes and rhythm stability in mice.

    PubMed

    Wicht, Helmut; Korf, Horst-Werner; Ackermann, Hanns; Ekhart, Daniel; Fischer, Claudia; Pfeffer, Martina

    2014-02-01

    Humans come in different chronotypes: The phase of their sleep-wake cycle with respect to the phase of the external, sidereal cycle of night and day differs. Colloquially, the early chronotypes are addressed as "larks," the late ones as "owls." The human chronotype can be quantified in hours and minutes of local time by determining the median of the sleep phase. Demographically, early and late human chronotypes differ with respect to the stability of their rhythms and the prevalence of several widespread diseases and risk factors, such as depression, nicotine abuse, and others. Inbred mice are widely used in chronobiological research as model organisms, but up to now there was no way to chronotype them. We have developed a method to chronotype mice in hours and fractions of hours by measuring the median of activity (MoA) and have shown that different mouse strains have significantly different MoAs and, thus, chronotypes. We have further developed methods to estimate the stability of the behavioral rhythms and found that "late" mice have relatively instable rhythms. Our methods permit the use of inbred mice for investigations into the molecular and genetic background of the chronotype and the prevalence of risks and diseases that are associated with it. PMID:24079808

  12. Differential short-term memorisation for vocal and instrumental rhythms.

    PubMed

    Klyn, Niall A M; Will, Udo; Cheong, Yong-Jeon; Allen, Erin T

    2016-07-01

    This study explores differential processing of vocal and instrumental rhythms in short-term memory with three decision (same/different judgments) and one reproduction experiment. In the first experiment, memory performance declined for delayed versus immediate recall, with accuracy for the two rhythms being affected differently: Musicians performed better than non-musicians on clapstick but not on vocal rhythms, and musicians were better on vocal rhythms in the same than in the different condition. Results for the second experiment showed that concurrent sub-vocal articulation and finger-tapping differentially affected the two rhythms and same/different decisions, but produced no evidence for articulatory loop involvement in delayed decision tasks. In a third experiment, which tested rhythm reproduction, concurrent sub-vocal articulation decreased memory performance, with a stronger deleterious effect on the reproduction of vocal than of clapstick rhythms. This suggests that the articulatory loop may only be involved in delayed reproduction not in decision tasks. The fourth experiment tested whether differences between filled and empty rhythms (continuous vs. discontinuous sounds) can explain the different memorisation of vocal and clapstick rhythms. Though significant differences were found for empty and filled instrumental rhythms, the differences between vocal and clapstick can only be explained by considering additional voice specific features. PMID:26274938

  13. Towards Active Tracking of Beating Heart Motion in the Presence of Arrhythmia for Robotic Assisted Beating Heart Surgery

    PubMed Central

    Tuna, E. Erdem; Karimov, Jamshid H.; Liu, Taoming; Bebek, Özkan; Fukamachi, Kiyotaka; Çavuşoğlu, M. Cenk

    2014-01-01

    In robotic assisted beating heart surgery, the control architecture for heart motion tracking has stringent requirements in terms of bandwidth of the motion that needs to be tracked. In order to achieve sufficient tracking accuracy, feed-forward control algorithms, which rely on estimations of upcoming heart motion, have been proposed in the literature. However, performance of these feed-forward motion control algorithms under heart rhythm variations is an important concern. In their past work, the authors have demonstrated the effectiveness of a receding horizon model predictive control-based algorithm, which used generalized adaptive predictors, under constant and slowly varying heart rate conditions. This paper extends these studies to the case when the heart motion statistics change abruptly and significantly, such as during arrhythmias. A feasibility study is carried out to assess the motion tracking capabilities of the adaptive algorithms in the occurrence of arrhythmia during beating heart surgery. Specifically, the tracking performance of the algorithms is evaluated on prerecorded motion data, which is collected in vivo and includes heart rhythm irregularities. The algorithms are tested using both simulations and bench experiments on a three degree-of-freedom robotic test bed. They are also compared with a position-plus-derivative controller as well as a receding horizon model predictive controller that employs an extended Kalman filter algorithm for predicting future heart motion. PMID:25048462

  14. Mean platelet volume is related with ischemic stroke in patients with sinus rhythm.

    PubMed

    Özkan, Buğra; Arik, Osman Z; Gözükara, Mehmet Y; Şahin, Durmuş Y; Topal, Salih; Uysal, Onur K; Elbasan, Zafer; Epçeliden, Tuncay; Çayli, Murat; Gür, Mustafa

    2016-07-01

    Stroke is the leading cause of disability worldwide. It is known that atrial fibrillation and left atrial enlargement contribute ischemic stroke, and mean platelet volume (MPV) increases in patients with ischemic stroke and atrial fibrillation. We aimed to determine whether higher MPV is associated with ischemic stroke in patients with sinus rhythm. We evaluated 74 patients in sinus rhythm and with ischemic stroke (Group 1) and 90 age-matched and sex-matched healthy individuals as control group (Group 2). After physical and echocardiographic examination, 24-48 h Holter monitoring and complete blood counts were studied. There were no statistically significant differences in age, sex rates, and comorbidities between groups. Left atrial diameter was higher in Group 1 than Group 2 (P = 0.001), but both were in normal range. MPV was significantly higher in Group 1 (P < 0.001) and was an independent determinant [odds ratio (OR): 1.840; P < 0.001; 95% confidence interval (CI) 1.330-2.545] of ischemic stroke with left atrial (OR: 1.138; P = 0.006; 95% CI 1.037-1.248). In conclusion, higher MPV is associated with acute ischemic stroke in patients with sinus rhythm and without heart failure or left atrial enlargement. MPV and left atrial diameter are independent predictors of ischemic stroke in this patient population. PMID:24686100

  15. Arm and wrist surface potential mapping for wearable ECG rhythm recording devices: a pilot clinical study

    NASA Astrophysics Data System (ADS)

    Lynn, W. D.; Escalona, O. J.; McEneaney, D. J.

    2013-06-01

    This study addresses an important question in the development of a ECG device that enables long term monitoring of cardiac rhythm. This device would utilise edge sensor technologies for dry, non-irritant skin contact suitable for distal limb application and would be supported by embedded ECG denoising processes. Contemporary ECG databases including those provided by MIT-BIH and Physionet are focused on interpretation of cardiac disease and rhythm tracking. The data is recorded using chest leads as in standard clinical practise. For the development of a peripherally located heart rhythm monitor, such data would be of limited use. To provide a useful database adequate for the development of the above mentioned cardiac monitoring device a unipolar body surface potential map from the left arm and wrist was gathered in 37 volunteer patients and characterized in this study. For this, the reference electrode was placed at the wrist. Bipolar far-field electrogram leads were derived and analysed. Factors such as skin variability, 50Hz noise interference, electrode contact noise, motion artifacts and electromyographic noise, presented a challenge. The objective was quantify the signal-to-noise ratio (SNR) at the far-field locations. Preliminary results reveal that an electrogram indicative of the QRS complex can be recorded on the distal portion of the left arm when denoised using signal averaging techniques.

  16. Factors related to sinus rhythm at discharge after radiofrequency ablation of permanent atrial fibrillation in patients undergoing mitral valve surgery.

    PubMed

    Rostagno, Carlo; Gelsomino, Sandro; Capecchi, Irene; Rossi, Alessandra; Montesi, Gian Franco; Stefàno, Pier Luigi

    2016-04-01

    Late recovery of sinus rhythm is unusual in patients with permanent AF treated by (radiofrequency) RF maze procedure during mitral valve surgery. Identification of clinical and instrumental preoperative factors predictive of early success of RF ablation in patients with permanent AF undergoing mitral valve surgery may improve selection of subjects to obtain long-term results. Hundred and thirty consecutive patients with permanent AF and mitral valve disease underwent modified RF maze procedure during concomitant mitral valve surgery. Rheumatic valve disease (61 pts) and mitral valve prolapse (41 pts) were the more common aetiology of valve abnormalities. Mitral valve replacement was performed in 54 % of patients and mitral valve repair in the remaining 46 %. Four patients died after surgery. At discharge, 87 patients (69 %) were in sinus rhythm (group 1) and 43 patients in AF persisted (group 2). At an average 24-month follow-up, sinus rhythm was present in 67 % of patients, and 33 % were in atrial fibrillation. In this period, late recovery of sinus rhythm was observed only in five patients, while eight discharged in sinus rhythm developed again atrial fibrillation. Among preoperative parameters at univariate analysis female sex, atrial fibrillation >24 months, left atrial diameter >54 mm, left atrial area >24 cm(2), rheumatic valve disease and NYHA class were associated with persistence of AF. At Cox regression multivariate analysis, increased left atrial area (OR 1.07 per unit increase-95 % CI 1.01-1.131) and rheumatic aetiology of valve disease (OR 4.52, 95 % CI 1.65-12.4) were associated with persistence of AF at hospital discharge. Persistence of AF after RF ablation in patients undergoing mitral valve surgery is related to aetiology, e.g. rheumatic valve disease, and to increasing left atrial diameter. Due to low rate of late recovery of sinus rhythm, indication to RF ablation associated with MV surgery should be carefully considered in patients with large

  17. Feedback control of human alpha rhythm from the central area.

    PubMed

    Potolicchio, S J; Zukerman, A S; Chernigovskaya, N V

    1979-09-01

    Twenty subjects, aged 17 to 25, were given from 5 to 10 sessions of training in controlling alpha. They were divided into three groups, respectively reinforced for increasing alpha from the central area, reinforced for decreasing alpha from the central area, and given noncontingent reinforcement. Compared with the initial baseline, the alpha of the noncontingent subjects did not change, while those reinforced for increases were reliably higher and those reinforced for decreases reliably lower than the noncontingent group. A slight trend toward improvement during successive sessions was not reliable. Since the experiment was conducted in the Soviet Union, the subjects had no expectations of an "alpha experience." Although tests showed a slight elevation in mood at the end of the sessions, there were no differences among the groups. There was an increase in reports of fatigue after the training sessions. There were no reports of using visual or somatomotor maneuvers as a means of controlling alpha. Furthermore, alpha rhythm control was not found to be consistently correlated with changes in heart rate, respiration, or mood, as determined by cross-correlation analysis. PMID:486587

  18. Circadian rhythms and fractal fluctuations in forearm motion

    NASA Astrophysics Data System (ADS)

    Hu, Kun; Hilton, Michael F.

    2005-03-01

    Recent studies have shown that the circadian pacemaker --- an internal body clock located in the brain which is normally synchronized with the sleep/wake behavioral cycles --- influences key physiologic functions such as the body temperature, hormone secretion and heart rate. Surprisingly, no previous studies have investigated whether the circadian pacemaker impacts human motor activity --- a fundamental physiologic function. We investigate high-frequency actigraph recordings of forearm motion from a group of young and healthy subjects during a forced desynchrony protocol which allows to decouple the sleep/wake cycles from the endogenous circadian cycle while controlling scheduled behaviors. We investigate both static properties (mean value, standard deviation), dynamical characteristics (long-range correlations), and nonlinear features (magnitude and Fourier-phase correlations) in the fluctuations of forearm acceleration across different circadian phases. We demonstrate that while the static properties exhibit significant circadian rhythms with a broad peak in the afternoon, the dynamical and nonlinear characteristics remain invariant with circadian phase. This finding suggests an intrinsic multi-scale dynamic regulation of forearm motion the mechanism of which is not influenced by the circadian pacemaker, thus suggesting that increased cardiac risk in the early morning hours is not related to circadian-mediated influences on motor activity.

  19. [Central EEG rhythm associated with movement and EEG rhythm associated with spatial reasoning: are they homologous?].

    PubMed

    Tarotin, I V; Ivanitsky, G A

    2014-01-01

    EEG rhythmical picture of subject's movement suppression and spatial-figurative task solving was examined and analyzed. Rhythms appearing during spatial reasoning and suppressed movements with the frequency of about 11 Hz were isolated. It was hypothesized that a functional link exists between these rhythms in the considered behavioral tests. To test the hypothesis and to reveal this connection, experiments were developed and carried out. Then the analysis of recorded EEG signals was conducted by applying Fourier transform, independent component analysis (ICA) and equivalent dipole source localization. Unexpected conclusion about the existence of a general mechanism of movement suppression was drawn. PMID:25975138

  20. Conventional rhythms enhance infants' and adults' perception of musical patterns.

    PubMed

    Trehub, Sandra E; Hannon, Erin E

    2009-01-01

    Listeners may favour particular rhythms because of their degree of conformity to culture-specific expectations or because of perceptual constraints that are apparent early in development. In two experiments we examined adults' and 6-month-old infants' detection of subtle rhythmic and melodic changes to two sequences of tones, a conventional rhythm that musically untrained adults rated as rhythmically good and an unconventional rhythm that was rated as poor. Detection of the changes was above chance in all conditions, but adults and infants performed more accurately in the context of the conventional rhythm. Unlike adults, who benefited from rhythmic conventionality only when detecting rhythmic changes, infants benefited when detecting melodic as well as rhythmic changes. The findings point to infant and adult parallels for some aspects of rhythm processing and to integrated perception of rhythm and melody early in life. PMID:19058799

  1. Activity in the ferret: oestradiol effects and circadian rhythms

    NASA Technical Reports Server (NTRS)

    Stockman, E. R.; Albers, H. E.; Baum, M. J.; Wurtman, R. J. (Principal Investigator)

    1985-01-01

    The present study was conducted to determine whether oestradiol increases activity in the European ferret (Mustela furo), whether this effect is sexually dimorphic, and whether a 24-h rhythm is present in the ferret's daily activity. The activity of male and female adult, postpubertally gonadectomized ferrets was monitored while they were maintained singly on a 13:11 light-dark cycle, before and after implantation with oestradiol-17 beta. Gonadectomized male and female ferrets exhibited equal levels of activity, and neither sex exhibited a significant change in activity following oestradiol implantation. None of the ferrets exhibited a strong circadian rhythm, although weak 24-h rhythms and shorter harmonic rhythms were present. Golden hamsters (Mesocricetus auratus), monitored in an identical manner, exhibited strong circadian rhythms. It was concluded that oestradiol administration may not cause an increase in activity in the ferret, and that this species lacks a strong circadian activity rhythm.

  2. Hypoxia and fetal heart development.

    PubMed

    Patterson, A J; Zhang, L

    2010-10-01

    Fetal hearts show a remarkable ability to develop under hypoxic conditions. The metabolic flexibility of fetal hearts allows sustained development under low oxygen conditions. In fact, hypoxia is critical for proper myocardial formation. Particularly, hypoxia inducible factor 1 (HIF-1) and vascular endothelial growth factor play central roles in hypoxia-dependent signaling in fetal heart formation, impacting embryonic outflow track remodeling and coronary vessel growth. Although HIF is not the only gene involved in adaptation to hypoxia, its role places it as a central figure in orchestrating events needed for adaptation to hypoxic stress. Although "normal" hypoxia (lower oxygen tension in the fetus as compared with the adult) is essential in heart formation, further abnormal hypoxia in utero adversely affects cardiogenesis. Prenatal hypoxia alters myocardial structure and causes a decline in cardiac performance. Not only are the effects of hypoxia apparent during the perinatal period, but prolonged hypoxia in utero also causes fetal programming of abnormality in the heart's development. The altered expression pattern of cardioprotective genes such as protein kinase c epsilon, heat shock protein 70, and endothelial nitric oxide synthase, likely predispose the developing heart to increased vulnerability to ischemia and reperfusion injury later in life. The events underlying the long-term changes in gene expression are not clear, but likely involve variation in epigenetic regulation. PMID:20712587

  3. Cardiac Arrhythmias and Abnormal Electrocardiograms After Acute Stroke.

    PubMed

    Ruthirago, Doungporn; Julayanont, Parunyou; Tantrachoti, Pakpoom; Kim, Jongyeol; Nugent, Kenneth

    2016-01-01

    Cardiac arrhythmias and electrocardiogram (ECG) abnormalities occur frequently but are often underrecognized after strokes. Acute ischemic and hemorrhagic strokes in some particular area of brain can disrupt central autonomic control of the heart, precipitating cardiac arrhythmias, ECG abnormalities, myocardial injury and sometimes sudden death. Identification of high-risk patients after acute stroke is important to arrange appropriate cardiac monitoring and effective management of arrhythmias, and to prevent cardiac morbidity and mortality. More studies are needed to better clarify pathogenesis, localization of areas associated with arrhythmias and practical management of arrhythmias and abnormal ECGs after acute stroke. PMID:26802767

  4. Automatic Evaluation of Speech Rhythm Instability and Acceleration in Dysarthrias Associated with Basal Ganglia Dysfunction.

    PubMed

    Rusz, Jan; Hlavnička, Jan; Čmejla, Roman; Růžička, Evžen

    2015-01-01

    Speech rhythm abnormalities are commonly present in patients with different neurodegenerative disorders. These alterations are hypothesized to be a consequence of disruption to the basal ganglia circuitry involving dysfunction of motor planning, programing, and execution, which can be detected by a syllable repetition paradigm. Therefore, the aim of the present study was to design a robust signal processing technique that allows the automatic detection of spectrally distinctive nuclei of syllable vocalizations and to determine speech features that represent rhythm instability (RI) and rhythm acceleration (RA). A further aim was to elucidate specific patterns of dysrhythmia across various neurodegenerative disorders that share disruption of basal ganglia function. Speech samples based on repetition of the syllable /pa/ at a self-determined steady pace were acquired from 109 subjects, including 22 with Parkinson's disease (PD), 11 progressive supranuclear palsy (PSP), 9 multiple system atrophy (MSA), 24 ephedrone-induced parkinsonism (EP), 20 Huntington's disease (HD), and 23 healthy controls. Subsequently, an algorithm for the automatic detection of syllables as well as features representing RI and RA were designed. The proposed detection algorithm was able to correctly identify syllables and remove erroneous detections due to excessive inspiration and non-speech sounds with a very high accuracy of 99.6%. Instability of vocal pace performance was observed in PSP, MSA, EP, and HD groups. Significantly increased pace acceleration was observed only in the PD group. Although not significant, a tendency for pace acceleration was observed also in the PSP and MSA groups. Our findings underline the crucial role of the basal ganglia in the execution and maintenance of automatic speech motor sequences. We envisage the current approach to become the first step toward the development of acoustic technologies allowing automated assessment of rhythm in dysarthrias. PMID:26258122

  5. Experiment K-7-35: Circadian Rhythms and Temperature Regulation During Spaceflight. Part 1; Circadian Rhythms and Temperature Regulation

    NASA Technical Reports Server (NTRS)

    Fuller, C. A.; Alpatov, A. M.; Hoban-Higgins, T. M.; Klimovitsky, V. Y.

    1994-01-01

    Mammals have developed the ability to adapt to most variations encountered in their everyday environment. For example, homeotherms have developed the ability to maintain the internal cellular environment at a relatively constant temperature. Also, in order to compensate for temporal variations in the terrestrial environment, the circadian timing system has evolved. However, throughout the evolution of life on earth, living organisms have been exposed to the influence of an unvarying level of earth's gravity. As a result changes in gravity produce adaptive responses which are not completely understood. In particular, spaceflight has pronounced effects on various physiological and behavioral systems. Such systems include body temperature regulation and circadian rhythms. This program has examined the influence of microgravity on temperature regulation and circadian timekeeping systems in Rhesus monkeys. Animals flown on the Soviet Biosatellite, COSMOS 2044, were exposed to 14 days of microgravity while constantly monitoring the circadian patterns temperature regulation, heart rate and activity. This experiment has extended our previous observations from COSMOS 1514, as well as providing insights into the physiological mechanisms that produce these changes.

  6. Chronic phase advance alters circadian physiological rhythms and peripheral molecular clocks.

    PubMed

    Wolff, Gretchen; Duncan, Marilyn J; Esser, Karyn A

    2013-08-01

    Shifting the onset of light, acutely or chronically, can profoundly affect responses to infection, tumor progression, development of metabolic disease, and mortality in mammals. To date, the majority of phase-shifting studies have focused on acute exposure to a shift in the timing of the light cycle, whereas the consequences of chronic phase shifts alone on molecular rhythms in peripheral tissues such as skeletal muscle have not been studied. In this study, we tested the effect of chronic phase advance on the molecular clock mechanism in two phenotypically different skeletal muscles. The phase advance protocol (CPA) involved 6-h phase advances (earlier light onset) every 4 days for 8 wk. Analysis of the molecular clock, via bioluminescence recording, in the soleus and flexor digitorum brevis (FDB) muscles and lung demonstrated that CPA advanced the phase of the rhythm when studied immediately after CPA. However, if the mice were placed into free-running conditions (DD) for 2 wk after CPA, the molecular clock was not phase shifted in the two muscles but was still shifted in the lung. Wheel running behavior remained rhythmic in CPA mice; however, the endogenous period length of the free-running rhythm was significantly shorter than that of control mice. Core body temperature, cage activity, and heart rate remained rhythmic throughout the experiment, although the onset of the rhythms was significantly delayed with CPA. These results provide clues that lifestyles associated with chronic environmental desynchrony, such as shift work, can have disruptive effects on the molecular clock mechanism in peripheral tissues, including both types of skeletal muscle. Whether this can contribute, long term, to increased incidence of insulin resistance/metabolic disease requires further study. PMID:23703115

  7. Aged rats show dominant modulation of lower frequency hippocampal theta rhythm during running.

    PubMed

    Li, Jia-Yi; Kuo, Terry B J; Yang, Cheryl C H

    2016-10-01

    Aging causes considerable decline in both physiological and mental functions, particularly cognitive function. The hippocampal theta rhythm (4-12Hz) is related to both cognition and locomotion. Aging-related findings of the frequency and amplitude of hippocampal theta oscillations are inconsistent and occasionally contradictory. This inconsistency may be due to the effects of the sleep/wake state and different frequency subbands being overlooked. We assumed that aged rats have lower responses of the hippocampal theta rhythm during running, which is mainly due to the dominant modulation of theta frequency subbands related to cognition. By simultaneously recording electroencephalography, physical activity (PA), and the heart rate (HR), this experiment explored the theta oscillations before, during, and after treadmill running at a constant speed in 8-week-old (adult) and 60-week-old (middle-aged) rats. Compared with adult rats, the middle-aged rats exhibited lower theta activity in all frequency ranges before running. Running increased the theta frequency (Frq, 4-12Hz), total activity of the whole theta band (total power, TP), activity of the middle theta frequency (MT, 6.5-9.5Hz), and PA in both age groups. However, the middle-aged rats still showed fewer changes in these parameters during the whole running process. After the waking baseline values were substracted, middle-aged rats showed significantly fewer differences in ΔFrq, ΔTP, and ΔMT but significantly more differences in low-frequency theta activity (4.0-6.5Hz) and HR than the adult rats did. Therefore, the decreasing activity and response of the whole theta band in the middle-aged rats resulted in dominant modulation of the middle to lower frequency (4.0-9.5Hz) theta rhythm. The different alterations in the theta rhythm during treadmill running in the two groups may reflect that learning decline with age. PMID:27496645

  8. Chronic phase advance alters circadian physiological rhythms and peripheral molecular clocks

    PubMed Central

    Wolff, Gretchen; Duncan, Marilyn J.

    2013-01-01

    Shifting the onset of light, acutely or chronically, can profoundly affect responses to infection, tumor progression, development of metabolic disease, and mortality in mammals. To date, the majority of phase-shifting studies have focused on acute exposure to a shift in the timing of the light cycle, whereas the consequences of chronic phase shifts alone on molecular rhythms in peripheral tissues such as skeletal muscle have not been studied. In this study, we tested the effect of chronic phase advance on the molecular clock mechanism in two phenotypically different skeletal muscles. The phase advance protocol (CPA) involved 6-h phase advances (earlier light onset) every 4 days for 8 wk. Analysis of the molecular clock, via bioluminescence recording, in the soleus and flexor digitorum brevis (FDB) muscles and lung demonstrated that CPA advanced the phase of the rhythm when studied immediately after CPA. However, if the mice were placed into free-running conditions (DD) for 2 wk after CPA, the molecular clock was not phase shifted in the two muscles but was still shifted in the lung. Wheel running behavior remained rhythmic in CPA mice; however, the endogenous period length of the free-running rhythm was significantly shorter than that of control mice. Core body temperature, cage activity, and heart rate remained rhythmic throughout the experiment, although the onset of the rhythms was significantly delayed with CPA. These results provide clues that lifestyles associated with chronic environmental desynchrony, such as shift work, can have disruptive effects on the molecular clock mechanism in peripheral tissues, including both types of skeletal muscle. Whether this can contribute, long term, to increased incidence of insulin resistance/metabolic disease requires further study. PMID:23703115

  9. Brain neural synchronization and functional coupling in Alzheimer's disease as revealed by resting state EEG rhythms.

    PubMed

    Babiloni, Claudio; Lizio, Roberta; Marzano, Nicola; Capotosto, Paolo; Soricelli, Andrea; Triggiani, Antonio Ivano; Cordone, Susanna; Gesualdo, Loreto; Del Percio, Claudio

    2016-05-01

    Alzheimer's disease (AD) is the most common type of neurodegenerative disorder, typically causing dementia along aging. AD is mainly characterized by a pathological extracellular accumulation of amyloid-beta peptides that affects excitatory and inhibitory synaptic transmission, inducing aberrant patterns in neuronal circuits. Growing evidence shows that AD targets cortical neuronal networks related to cognitive functions including episodic memory and visuospatial attention. This is partially reflected by the abnormal mechanisms of cortical neural synchronization and coupling that generate resting state electroencephalographic (EEG) rhythms. The cortical neural synchronization is typically indexed by EEG power density. The EEG coupling between electrode pairs probes functional (inter-relatedness of EEG signals) and effective (casual effect from one over the other electrode) connectivity. The former is typically indexed by synchronization likelihood (linear and nonlinear) or spectral coherence (linear), the latter by granger causality or information theory indexes. Here we reviewed literature concerning EEG studies in condition of resting state in AD and mild cognitive impairment (MCI) subjects as a window on abnormalities of the cortical neural synchronization and functional and effective connectivity. Results showed abnormalities of the EEG power density at specific frequency bands (<12Hz) in the MCI and AD populations, associated with an altered functional and effective EEG connectivity among long range cortical networks (i.e. fronto-parietal and fronto-temporal). These results suggest that resting state EEG rhythms reflect the abnormal cortical neural synchronization and coupling in the brain of prodromal and overt AD subjects, possibly reflecting dysfunctional neuroplasticity of the neural transmission in long range cortical networks. PMID:25660305

  10. Evaluation of regression-based 3-D shoulder rhythms.

    PubMed

    Xu, Xu; Dickerson, Clark R; Lin, Jia-Hua; McGorry, Raymond W

    2016-08-01

    The movements of the humerus, the clavicle, and the scapula are not completely independent. The coupled pattern of movement of these bones is called the shoulder rhythm. To date, multiple studies have focused on providing regression-based 3-D shoulder rhythms, in which the orientations of the clavicle and the scapula are estimated by the orientation of the humerus. In this study, six existing regression-based shoulder rhythms were evaluated by an independent dataset in terms of their predictability. The datasets include the measured orientations of the humerus, the clavicle, and the scapula of 14 participants over 118 different upper arm postures. The predicted orientations of the clavicle and the scapula were derived from applying those regression-based shoulder rhythms to the humerus orientation. The results indicated that none of those regression-based shoulder rhythms provides consistently more accurate results than the others. For all the joint angles and all the shoulder rhythms, the RMSE are all greater than 5°. Among those shoulder rhythms, the scapula lateral/medial rotation has the strongest correlation between the predicted and the measured angles, while the other thoracoclavicular and thoracoscapular bone orientation angles only showed a weak to moderate correlation. Since the regression-based shoulder rhythm has been adopted for shoulder biomechanical models to estimate shoulder muscle activities and structure loads, there needs to be further investigation on how the predicted error from the shoulder rhythm affects the output of the biomechanical model. PMID:26253991

  11. Circadian rhythm of body temperature during prolonged undersea voyages.

    PubMed

    Colquhoun, W P; Paine, M W; Fort, A

    1978-05-01

    Circadian rhythms of oral temperature were assessed in 12 watchkeepers during a prolonged submarine voyage and compared with a "standard" rhythm obtained from nonwatchkeepers ashore. Initially, the parameters of the rhythms were similar to those of the standard; however, among eight ratings working 4-h watches in a rapidly rotating cycle, considerable changes in the rhythms occurred as the voyage progressed, and concurrent alterations in sleep patterning were observed. The most characteristic change in the rhythm was a marked decline in its amplitude. In most subjects, the rhythm also tended to depart from its original circadian pattern; in at least one case, it effectively disintegrated. One subject's rhythm appeared to "free-run" with a period greater than 24 h. A strong circadian rhythm was maintained in only one of these eight subjects. In four officers whose watch times were at fixed hours, adaptation of the rhythm to unusual times of sleep occurred in 2 of 3 cases where the schedule demanded it. The results are discussed in relation to the design of optimal watchkeeping systems for submariners. PMID:655989

  12. Heart regeneration.

    PubMed

    Breckwoldt, Kaja; Weinberger, Florian; Eschenhagen, Thomas

    2016-07-01

    Regenerating an injured heart holds great promise for millions of patients suffering from heart diseases. Since the human heart has very limited regenerative capacity, this is a challenging task. Numerous strategies aiming to improve heart function have been developed. In this review we focus on approaches intending to replace damaged heart muscle by new cardiomyocytes. Different strategies for the production of cardiomyocytes from human embryonic stem cells or human induced pluripotent stem cells, by direct reprogramming and induction of cardiomyocyte proliferation are discussed regarding their therapeutic potential and respective advantages and disadvantages. Furthermore, different methods for the transplantation of pluripotent stem cell-derived cardiomyocytes are described and their clinical perspectives are discussed. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. PMID:26597703

  13. Hypoplastic left heart syndrome

    MedlinePlus

    HLHS; Congenital heart - hypoplastic left heart; Cyanotic heart disease - hypoplastic left heart ... Hypoplastic left heart is a rare type of congenital heart disease. It is more common in males than in females. As ...

  14. Release of acetylcholine by chick embryo heart before innervation

    PubMed Central

    Coraboeuf, E.; Le Douarin, G.; Obrecht-Coutris, G.

    1970-01-01

    1. In chick embryo hearts, 3-day-old and not yet innervated, repetitive direct stimulation causes a transitory inhibition of the spontaneous rhythm. 2. The degree of post-stimulation inhibition depends on the frequency and duration of the artificial stimulation and on the concentration of K and Ca ions in the extracellular solution. 3. After treatment with atropine (10-5 g/ml.) post-stimulation inhibition is no longer observed. The spontaneous rhythm is accelerated by atropine. The findings therefore suggest that an ACh-like substance is released from the non-innervated embryonic heart during activity. 4. By use of the dorsal muscle of the leech for biological assay the liberation of an ACh-like substance from the non-innervated embryonic heart was confirmed. ImagesPlate 1 PMID:5498489

  15. Standing down Straight: Jump Rhythm Technique's Rhythm-Driven, Community-Directed Approach to Dance Education

    ERIC Educational Resources Information Center

    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,…

  16. In vitro circadian rhythms: imaging and electrophysiology.

    PubMed

    Beaulé, Christian; Granados-Fuentes, Daniel; Marpegan, Luciano; Herzog, Erik D

    2011-06-30

    In vitro assays have localized circadian pacemakers to individual cells, revealed genetic determinants of rhythm generation, identified molecular players in cell-cell synchronization and determined physiological events regulated by circadian clocks. Although they allow strict control of experimental conditions and reduce the number of variables compared with in vivo studies, they also lack many of the conditions in which cellular circadian oscillators normally function. The present review highlights methods to study circadian timing in cultured mammalian cells and how they have shaped the hypothesis that all cells are capable of circadian rhythmicity. PMID:21819387

  17. In vitro circadian rhythms: imaging and electrophysiology

    PubMed Central

    Beaulé, Christian; Granados-Fuentes, Daniel; Marpegan, Luciano; Herzog, Erik D.

    2013-01-01

    In vitro assays have localized circadian pacemakers to individual cells, revealed genetic determinants of rhythm generation, identified molecular players in cell-cell synchronization and determined physiological events regulated by circadian clocks. Although they allow strict control of experimental conditions and reduce the number of variables compared with in vivo studies, they also lack many of the conditions in which cellular circadian oscillators normally function. The present review highlights methods to study circadian timing in cultured mammalian cells and how they have shaped the hypothesis that all cells are capable of circadian rhythmicity. PMID:21819387

  18. Scapulothoracic rhythm in normal male volunteers.

    PubMed

    Talkhani, I S; Kelly, C P

    1997-01-01

    Dynamic pattern of Scapulothoracic rhythm during arm abduction in scapular plane is studied using computer-imaging technique. Aim of the study is to produce a reproducible and reliable way of calculating the scapular movement and glenohumeral movement using least possible roentgenographic exposure. Moving X-ray screening picture of the shoulder joint is analysed using video capture computer programme and the images at different degrees of abduction are then analysed for scapular movement using computer aided designer and drafting software. Results were comparable to the authoritative shoulder analysis carried out in the past, the difference of radiation exposure, approximately 10 times less. PMID:9603061

  19. How does the brain create rhythms?

    PubMed

    Szirmai, Imre

    2010-01-30

    Connection was found between rhythmic cortical activity and motor control. The 10 Hz micro-rhythm and the 20-30 Hz bursts represent two functional states of the somatomotor system. A correspondence of the central micro-rhythm of the motor cortex and the physiological hand tremor (8-12 Hz) is presumed. The precise tuning of the motor system can be estimated by the frequency of repetitive finger movements. In complex tapping exercise, the index finger is the most skillful, the 3rd, 4th and 5th fingers keep rhythm with less precision. It was found that the organization of mirror movements depends on the cortical representation of fingers. Mirror finger movements are more regular if the subject begins the motor action with the 5th (small) finger. Concerning cortical regulation of finger movements, it was suggested that there are two time-keeping systems in the brain; one with a sensitivity above and another with a sensitivity below the critical frequency of 3 Hz. The preferred meter which helps to maintain synchronous finger movements is the cadence of 4/4 and 8/8. We observed that the unlearned inward-outward sequential finger movement was equally impaired in nonmusician controls and patients with Parkinson-disease. In movement disorders, the ability of movement and the "clock-mechanism" are equally involved. The polyrhythmic finger movement is not our inborn ability, it has to be learned. The "timer" function, which regulates the rhythmic movement, is presumably localised in the basal ganglia or in the cerebellum. The meter of the music is built on the reciprocal values of 2 raised to the second to fifth power (1/1(2), 1/2(2), 1/2(3), 1/2(4), 1/2(5)). The EEG frequencies that we consider important in the regulation of conscious motor actions are approximately in the same domain (4, 8, 16, 32, 64 Hz). During music performance, an important neural process is the coupling of distant brain areas. Concerning melody, the musical taste of Europeans is octave-based. Musical

  20. Effects of 9-hour time zone changes on fatigue and circadian rhythms of sleep/wake and core temperature

    NASA Technical Reports Server (NTRS)

    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.

  1. The Teaching of Abnormal Psychology through the Cinema.

    ERIC Educational Resources Information Center

    Nissim-Sabat, Denis

    1979-01-01

    Describes abnormal psychology course centered around films which include "King of Hearts,""A Woman Under the Influence,""David and Lisa,""In Cold Blood," and "The Boys in the Band." Each film deals with a fundamental concept such as psychopathology, neurosis, psychosis, insanity, and sexuality. (KC)

  2. ELECTROCARDIOGRAPHIC ABNORMALITIES AMONG MEXICAN AMERICANS: CORRELATIONS WITH DIABETES, OBESITY, AND THE METABOLIC SYNDROME

    PubMed Central

    Queen, Saulette R.; Smulevitz, Beverly; Rentfro, Anne R.; Vatcheva, Kristina P.; Kim, Hyunggun; McPherson, David D.; Hanis, Craig L.; Fisher-Hoch, Susan P.; McCormick, Joseph B.; Laing, Susan T.

    2012-01-01

    SUMMARY BACKGROUND Resting ischemic electrocardiographic abnormalities have been associated with cardiovascular mortality. Simple markers of abnormal autonomic tone have also been associated with diabetes, obesity, and the metabolic syndrome in some populations. Data on these electrocardiographic abnormalities and correlations with coronary risk factors are lacking among Mexican Americans wherein these conditions are prevalent. OBJECTIVE This study aimed to evaluate the prevalent resting electrocardiographic abnormalities among community-dwelling Mexican Americans, and correlate these findings with coronary risk factors, particularly diabetes, obesity, and the metabolic syndrome. METHODS Study subjects (n=1280) were drawn from the Cameron County Hispanic Cohort comprised of community-dwelling Mexican Americans living in Brownsville, Texas at the United States-Mexico border. Ischemic electrocardiographic abnormalities were defined as presence of ST/T wave abnormalities suggestive of ischemia, abnormal Q waves, and left bundle branch block. Parameters that reflect autonomic tone, such as heart rate-corrected QT interval and resting heart rate, were also measured. RESULTS Ischemic electrocardiographic abnormalities were more prevalent among older persons and those with hypertension, diabetes, obesity, and the metabolic syndrome. Subjects in the highest quartiles of QTc interval and resting heart rate were also more likely to be diabetic, hypertensive, obese, or have the metabolic syndrome. CONCLUSIONS Among Mexican Americans, persons with diabetes, obesity, and the metabolic syndrome were more likely to have ischemic electrocardiographic abnormalities, longer QTc intervals, and higher resting heart rates. A resting electrocardiogram can play a complementary role in the comprehensive evaluation of cardiovascular risk in this minority population. PMID:23515880

  3. Effects of L-Dopa on circadian rhythms of 6-OHDA striatal lesioned rats: a radiotelemetric study.

    PubMed

    Boulamery, Audrey; Simon, Nicolas; Vidal, Johanna; Bruguerolle, Bernard

    2010-01-01

    Temporal variation in the motor function of Parkinson's disease (PD) patients suggests the potential importance of a chronobiological and chronopharmacological approach in its clinical management. We previously documented the effects of striatal injection of 6-OHDA (as an animal model of PD) on the circadian rhythms of temperature (T), heart rate (HR), and locomotor activity (A). The present work assessed the possible influence of L-Dopa on these same rhythms in the 6-OHDA animal model of PD. The study began after a four-week recovery period following surgical implantation of telemetric devices to monitor the study variables and/or anaesthesia. The study was divided into an initial one-week control period (W1) for baseline measurement of T, HR, and A rhythms. Thereafter, stereotaxic 6-OHDA lesioning was done. and a second monitoring for two weeks followed (W2, W3). Rats were then randomly divided into two groups: eight control rats received, via a mini-osmotic pump implanted subcutaneously, the excipient saline; the other eight rats received L-Dopa (100 mg/kg SC/day). After a seven-day period (W4), the pumps were removed and the T, HR, and A rhythms were monitored for two weeks (W5 and W6). To control for 6-OHDA striatal dopamine-induced depletion, 12 other rats were injected by identical methods (eight rats with 6-OHDA and four controls with saline) and sacrificed at W1, W3, and W5 for dopamine striatal content determination. To verify the delivery of levodopa from the osmotic pumps, plasma levels of levodopa and its main metabolites 3-OMD, DOPAC, and HVA were determined on separate group of rats receiving the drug under the same experimental conditions (osmotic pumps delivering continuously 10 microl/h for seven days, 100 mg/kg/subcutaneously). Our results agree with previously reported rhythmic changes induced by 6-OHDA--loss of circadian rhythmicity or changes in the main parameters of the registered rhythms. When circadian rhythmicity was abolished, L

  4. Atrial rhythm influences catheter tissue contact during radiofrequency catheter ablation of atrial fibrillation: comparison of contact force between sinus rhythm and atrial fibrillation.

    PubMed

    Matsuda, Hisao; Parwani, Abdul Shokor; Attanasio, Philipp; Huemer, Martin; Wutzler, Alexander; Blaschke, Florian; Haverkamp, Wilhelm; Boldt, Leif-Hendrik

    2016-09-01

    Catheter tissue contact force (CF) is an important factor for durable lesion formation during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Since CF varies in the beating heart, atrial rhythm during RFCA may influence CF. A high-density map and RFCA points were obtained in 25 patients undergoing RFCA of AF using a CF-sensing catheter (Tacticath, St. Jude Medical). The operators were blinded to the CF information. Contact type was classified into three categories: constant, variable, and intermittent contact. Average CF and contact type were analyzed according to atrial rhythm (SR vs. AF) and anatomical location. A total of 1364 points (891 points during SR and 473 points during AF) were analyzed. Average CFs showed no significant difference between SR (17.2 ± 11.3 g) and AF (17.2 ± 13.3 g; p = 0.99). The distribution of points with an average CF of ≥20 and <10 g also showed no significant difference. However, the distribution of excessive CF (CF ≥40 g) was significantly higher during AF (7.4 %) in comparison with SR (4.2 %; p < 0.05). At the anterior area of the right inferior pulmonary vein (RIPV), the average CF during AF was significantly higher than during SR (p < 0.05). Constant contact was significantly higher during AF (32.2 %) when compared to SR (9.9 %; p < 0.01). Although the average CF was not different between atrial rhythms, constant contact was more often achievable during AF than it was during SR. However, excessive CF also seems to occur more frequently during AF especially at the anterior part of RIPV. PMID:26498938

  5. Accelerated idioventricular rhythm of infundibular origin in patients with a concealed form of arrhythmogenic right ventricular dysplasia.

    PubMed Central

    Martini, B; Nava, A; Thiene, G; Buja, G F; Canciani, B; Miraglia, G; Scognamiglio, R; Boffa, G M; Daliento, L

    1988-01-01

    Five apparently healthy people (aged 16-47) presented with recurrent episodes of accelerated idioventricular rhythm characterised by left bundle branch block and right axis deviation. Clinical history, physical findings, basic electrocardiogram, chest x ray, and blood tests were within normal limits in all. Holter monitoring, exercise stress test, and electrophysiological study (in three patients) showed that accelerated idioventricular rhythm was mainly bradycardia dependent, easily suppressed by effort and overdrive pacing, and originated from the outflow tract of the right ventricle. The mechanism could be enhanced automaticity. Data from cross sectional echocardiography (in all patients) and from haemodynamic evaluation (in three) identified structural or wall motion abnormalities of the right ventricle or both without appreciable dilatation of the ventricle. Biopsy specimens of the right ventricular endomyocardium showed fibrosis in one patient, fibrosis and fatty infiltration in the second, and pronounced fatty infiltration in the third. These results show that some patients with accelerated idioventricular rhythm have right ventricular abnormalities that are typical of the localised and concealed forms of arrhythmogenic right ventricular dysplasia. Images Fig 1 Fig 2 Fig 3 Fig 4 Fig 5 PMID:3382568

  6. Heart Failure

    MedlinePlus

    ... blood the way it should. It can affect one or both sides of the heart. The weakening of the heart's pumping ability causes Blood and fluid to back up into the lungs The buildup of fluid in the feet, ankles and legs - called edema Tiredness and shortness of breath Common causes of ...

  7. Having Heart.

    PubMed

    Cochrane, Christine

    2015-01-01

    A heart comes in many forms. This article shares the experience of behavioral health nurses caring for a suicidal patient who needs a heart. As a team, the nurses and their patient shared the journey of what it takes to achieve an optimum quality of life with a left ventricular assist device (LVAD) while battling mental illness. PMID:26731919

  8. Temperature compensation and entrainment in circadian rhythms

    NASA Astrophysics Data System (ADS)

    Bodenstein, C.; Heiland, I.; Schuster, S.

    2012-06-01

    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.

  9. Melatonin rhythms in Pony mares and foals.

    PubMed

    Kilmer, D M; Sharp, D C; Berglund, L A; Grubaugh, W; McDowell, K J; Peck, L S

    1982-01-01

    Melatonin concentrations in intact (N = 3) and sham-operated (N = 3) mares during March were greater (P less than 0 . 05) during the night than during the day, but this pattern was not seen in 3 mares from which the superior cervical ganglia had been removed bilaterally. When 4 Pony mares were exposed to a photoperiod of 10L:14D for 3 weeks and then to continuous darkness (0L:24D) for another 3 weeks, melatonin levels were greater (P less than 0 . 05) at the end of the 0L:24D period than during the earlier period and still displayed rhythmic fluctuations but were no longer co-ordinated with equivalent day/night rhythms or among mares. When melatonin rhythms were monitored in 3 mares and their foals housed in open pens exposed to natural lighting, significant time trends in melatonin concentrations were observed in mares when the foals were aged 1-3, 4-6 and 7-11 weeks, but foals did not display significant times trends in melatonin until they were 7-11 weeks old. PMID:6962864

  10. Circadian Rhythms, Sleep Deprivation, and Human Performance

    PubMed Central

    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

  11. The effect of stress on circadian rhythms.

    PubMed

    Brodan, V; Kuhn, E; Veselková, A; Kaucká, J

    1982-01-01

    The authors chose four types of intensive stress in man and show their effect on the circadian rhythms of selected parameters. Sleep deprivation reduces mean sideraemia and oscilation amplitudes. The morning rhythm maximum shifts to early morning hours. Acute fasting does not change the biorhythm of serum iron despite that mean sideraemia increases. On the other hand, realimentation is associated with a marked drop of iron level and a shift of the morning maximum to early afternoon hours. Stress induced by isolation in humid warm environment initiates a decrease of systolic blood pressure. While biorhythm amplitude remains unchanged peak systolic pressure moves from the usual 18 to 20 hours up to 23 to 24 hours. Stress caused by diagnostic cardiac catheterization results in biorhythm inversion of the urinary excretion of catecholamines and 17-OH-corticoids. On the day of catheterization, performed in all cases in the morning hours, the usual morning peak values of adrenaline shifted to afternoon hours and those of noradrenaline and 17-OH-corticoids even to late night hours. For practical purposes, biorhythm changes can be used as indicators of the effect and intensity of stress. PMID:7075389

  12. Rhythms for Cognition: Communication through Coherence.

    PubMed

    Fries, Pascal

    2015-10-01

    I propose that synchronization affects communication between neuronal groups. Gamma-band (30-90 Hz) synchronization modulates excitation rapidly enough that it escapes the following inhibition and activates postsynaptic neurons effectively. Synchronization also ensures that a presynaptic activation pattern arrives at postsynaptic neurons in a temporally coordinated manner. At a postsynaptic neuron, multiple presynaptic groups converge, e.g., representing different stimuli. If a stimulus is selected by attention, its neuronal representation shows stronger and higher-frequency gamma-band synchronization. Thereby, the attended stimulus representation selectively entrains postsynaptic neurons. The entrainment creates sequences of short excitation and longer inhibition that are coordinated between pre- and postsynaptic groups to transmit the attended representation and shut out competing inputs. The predominantly bottom-up-directed gamma-band influences are controlled by predominantly top-down-directed alpha-beta-band (8-20 Hz) influences. Attention itself samples stimuli at a 7-8 Hz theta rhythm. Thus, several rhythms and their interplay render neuronal communication effective, precise, and selective. PMID:26447583

  13. Circadian rhythm and its role in malignancy

    PubMed Central

    2010-01-01

    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. PMID:20353609

  14. Subjective pain perception mediated by alpha rhythms.

    PubMed

    Peng, Weiwei; Babiloni, Claudio; Mao, Yanhui; Hu, Yong

    2015-07-01

    Suppression of spontaneous alpha oscillatory activities, interpreted as cortical excitability, was observed in response to both transient and tonic painful stimuli. The changes of alpha rhythms induced by pain could be modulated by painful sensory inputs, experimental tasks, and top-down cognitive regulations such as attention. The temporal and spatial characteristics, as well as neural functions of pain induced alpha responses, depend much on how these factors contribute to the observed alpha event-related desynchronization/synchronization (ERD/ERS). How sensory-, task-, and cognitive-related changes of alpha oscillatory activities interact in pain perception process is reviewed in the current study, and the following conclusions are made: (1) the functional inhibition hypothesis that has been proposed in auditory and visual modalities could be applied also in pain modality; (2) the neural functions of pain induced alpha ERD/ERS were highly dependent on the cortical regions where it is observed, e.g., somatosensory cortex alpha ERD/ERS in pain perception for painful stimulus processing; (3) the attention modulation of pain perception, i.e., influences on the sensory and affective dimensions of pain experience, could be mediated by changes of alpha rhythms. Finally, we propose a model regarding the determinants of pain related alpha oscillatory activity, i.e., sensory-discriminative, affective-motivational, and cognitive-modulative aspects of pain experience, would affect and determine pain related alpha oscillatory activities in an integrated way within the distributed alpha system. PMID:26026894

  15. Morphological abnormalities in elasmobranchs.

    PubMed

    Moore, A B M

    2015-08-01

    A total of 10 abnormal free-swimming (i.e., post-birth) elasmobranchs are reported from The (Persian-Arabian) Gulf, encompassing five species and including deformed heads, snouts, caudal fins and claspers. The complete absence of pelvic fins in a milk shark Rhizoprionodon acutus may be the first record in any elasmobranch. Possible causes, including the extreme environmental conditions and the high level of anthropogenic pollution particular to The Gulf, are briefly discussed. PMID:25903257

  16. Improving the performance of cardiac abnormality detection from PCG signal

    NASA Astrophysics Data System (ADS)

    Sujit, N. R.; Kumar, C. Santhosh; Rajesh, C. B.

    2016-03-01

    The Phonocardiogram (PCG) signal contains important information about the condition of heart. Using PCG signal analysis prior recognition of coronary illness can be done. In this work, we developed a biomedical system for the detection of abnormality in heart and methods to enhance the performance of the system using SMOTE and AdaBoost technique have been presented. Time and frequency domain features extracted from the PCG signal is input to the system. The back-end classifier to the system developed is Decision Tree using CART (Classification and Regression Tree), with an overall classification accuracy of 78.33% and sensitivity (alarm accuracy) of 40%. Here sensitivity implies the precision obtained from classifying the abnormal heart sound, which is an essential parameter for a system. We further improve the performance of baseline system using SMOTE and AdaBoost algorithm. The proposed approach outperforms the baseline system by an absolute improvement in overall accuracy of 5% and sensitivity of 44.92%.

  17. Chromosome abnormalities in glioma

    SciTech Connect

    Li, Y.S.; Ramsay, D.A.; Fan, Y.S.

    1994-09-01

    Cytogenetic studies were performed in 25 patients with gliomas. An interesting finding was a seemingly identical abnormality, an extra band on the tip of the short arm of chromosome 1, add(1)(p36), in two cases. The abnormality was present in all cells from a patient with a glioblastoma and in 27% of the tumor cells from a patient with a recurrent irradiated anaplastic astrocytoma; in the latter case, 7 unrelated abnormal clones were identified except 4 of those clones shared a common change, -Y. Three similar cases have been described previously. In a patient with pleomorphic astrocytoma, the band 1q42 in both homologues of chromosome 1 was involved in two different rearrangements. A review of the literature revealed that deletion of the long arm of chromosome 1 including 1q42 often occurs in glioma. This may indicate a possible tumor suppressor gene in this region. Cytogenetic follow-up studies were carried out in two patients and emergence of unrelated clones were noted in both. A total of 124 clonal breakpoints were identified in the 25 patients. The breakpoints which occurred three times or more were: 1p36, 1p22, 1q21, 1q25, 3q21, 7q32, 8q22, 9q22, 16q22, and 22q13.

  18. [Congenital foot abnormalities].

    PubMed

    Delpont, M; Lafosse, T; Bachy, M; Mary, P; Alves, A; Vialle, R

    2015-03-01

    The foot may be the site of birth defects. These abnormalities are sometimes suspected prenatally. Final diagnosis depends on clinical examination at birth. These deformations can be simple malpositions: metatarsus adductus, talipes calcaneovalgus and pes supinatus. The prognosis is excellent spontaneously or with a simple orthopedic treatment. Surgery remains outstanding. The use of a pediatric orthopedist will be considered if malposition does not relax after several weeks. Malformations (clubfoot, vertical talus and skew foot) require specialized care early. Clubfoot is characterized by an equine and varus hindfoot, an adducted and supine forefoot, not reducible. Vertical talus combines equine hindfoot and dorsiflexion of the forefoot, which is performed in the midfoot instead of the ankle. Skew foot is suspected when a metatarsus adductus is resistant to conservative treatment. Early treatment is primarily orthopedic at birth. Surgical treatment begins to be considered after walking age. Keep in mind that an abnormality of the foot may be associated with other conditions: malposition with congenital hip, malformations with syndromes, neurological and genetic abnormalities. PMID:25524290

  19. Circadian Activity Rhythms, Time Urgency, and Achievement Concerns.

    ERIC Educational Resources Information Center

    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…

  20. Neglect of Biological Rhythms in High School Biology Texts.

    ERIC Educational Resources Information Center

    Ahlgren, Andrew; Nelson, Julie Ann

    1979-01-01

    This article developed from a survey of the five most popular biology texts which promote the theory of invariant homeostasis rather than biological rhythms. The popular fad of "birthdate biorhythms" is discussed in relation to providing education on biological rhythms and its legitimacy to the public. (SA)

  1. A novel animal model linking adiposity to altered circadian rhythms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. Rhythm's Gonna Get You: Regular Meter Facilitates Semantic Sentence Processing

    ERIC Educational Resources Information Center

    Rothermich, Kathrin; Schmidt-Kassow, Maren; Kotz, Sonja A.

    2012-01-01

    Rhythm is a phenomenon that fundamentally affects the perception of events unfolding in time. In language, we define "rhythm" as the temporal structure that underlies the perception and production of utterances, whereas "meter" is defined as the regular occurrence of beats (i.e. stressed syllables). In stress-timed languages such as German, this…

  3. Yes, circadian rhythms actually do affect almost everything.

    PubMed

    Dunlap, Jay C; Loros, Jennifer J

    2016-07-01

    Circadian rhythms in the level of intracellular Mg appear to be widely conserved phylogenetically, and have the potential to impact nearly all aspects of metabolism. Moreover, the clock regulates the ion channels that generate the rhythm, demonstrating that the whole cell operates as a circadian system. PMID:27241553

  4. A Rhythm Recognition Computer Program to Advocate Interactivist Perception

    ERIC Educational Resources Information Center

    Buisson, Jean-Christophe

    2004-01-01

    This paper advocates the main ideas of the interactive model of representation of Mark Bickhard and the assimilation/accommodation framework of Jean Piaget, through a rhythm recognition demonstration program. Although completely unsupervised, the program progressively learns to recognize more and more complex rhythms struck on the user's keyboard.…

  5. Effects of Some Aspects of Rhythm on Tempo Perception.

    ERIC Educational Resources Information Center

    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.…

  6. Perceptual Tests of Rhythmic Similarity: II. Syllable Rhythm

    ERIC Educational Resources Information Center

    Kim, Jeesun; Davis, Chris; Cutler, Anne

    2008-01-01

    To segment continuous speech into its component words, listeners make use of language rhythm; because rhythm differs across languages, so do the segmentation procedures which listeners use. For each of stress-, syllable-and mora-based rhythmic structure, perceptual experiments have led to the discovery of corresponding segmentation procedures. In…

  7. Dissociable systems of working memory for rhythm and melody.

    PubMed

    Jerde, Trenton A; Childs, Stephanie K; Handy, Sarah T; Nagode, Jennifer C; Pardo, José V

    2011-08-15

    Specialized neural systems are engaged by the rhythmic and melodic components of music. Here, we used PET to measure regional cerebral blood flow (rCBF) in a working memory task for sequences of rhythms and melodies, which were presented in separate blocks. Healthy subjects, without musical training, judged whether a target rhythm or melody was identical to a series of subsequently presented rhythms or melodies. When contrasted with passive listening to rhythms, working memory for rhythm activated the cerebellar hemispheres and vermis, right anterior insular cortex, and left anterior cingulate gyrus. These areas were not activated in a contrast between passive listening to rhythms and a non-auditory control, indicating their role in the temporal processing that was specific to working memory for rhythm. The contrast between working memory for melody and passive listening to melodies activated mainly a right-hemisphere network of frontal, parietal, and temporal cortices: areas involved in pitch processing and auditory working memory. Overall, these results demonstrate that rhythm and melody have unique neural signatures not only in the early stages of auditory processing, but also at the higher cognitive level of working memory. PMID:21645625

  8. Electrocardiogram of the failing heart.

    PubMed

    Hombach, Vinzenz

    2002-09-01

    In the failing heart general specific (e.g., Q-waves after acute myocardial infarction, persistent ST-elevations in post-myocardial infarction left ventricular aneurysm) and unspecific ECG changes (e.g., left bundle branch block, right bundle branch block, ST-T-alterations due to digitalis glycosides or antiarrhythmic drugs) may be seen in the conventional 12-lead ECG. In addition, atrial and ventricular tachy-arrhythmias may be detected and quantified by 24-hour-Holter ECG recordings, that may be relevant for a worse prognosis of patients with congestive heart failure. Heart rate variability as the most relevant derived ECG parameter of sympathetic tone fluctuations may be of important prognostic significance in congestive heart failure patients. An abnormal signal averaged P-wave duration may predict the incidence of atrial fibrillation, as may apply to QRS-prolongation and/or ventricular late potentials in the signal averaged ECG for the incidence of serious life-threatening ventricular tachy-arrhythmias or death from pump failure. Last but not least, cardiac repolarization abnormalities may be detected by QT dispersion-, QT-/QTc-fluctuation- or T-wave alternans studies, but the true prognostic significance of these parameters for predicting sudden cardiac death or death from pump failure in patients with congestive heart failure remains unclear. PMID:12114840

  9. Abnormal pressures as hydrodynamic phenomena

    USGS Publications Warehouse

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  10. Daily Rhythms in Mosquitoes and Their Consequences for Malaria Transmission.

    PubMed

    Rund, Samuel S C; O'Donnell, Aidan J; Gentile, James E; Reece, Sarah E

    2016-01-01

    The 24-h day involves cycles in environmental factors that impact organismal fitness. This is thought to select for organisms to regulate their temporal biology accordingly, through circadian and diel rhythms. In addition to rhythms in abiotic factors (such as light and temperature), biotic factors, including ecological interactions, also follow daily cycles. How daily rhythms shape, and are shaped by, interactions between organisms is poorly understood. Here, we review an emerging area, namely the causes and consequences of daily rhythms in the interactions between vectors, their hosts and the parasites they transmit. We focus on mosquitoes, malaria parasites and vertebrate hosts, because this system offers the opportunity to integrate from genetic and molecular mechanisms to population dynamics and because disrupting rhythms offers a novel avenue for disease control. PMID:27089370

  11. The role of circadian rhythm in breast cancer

    PubMed Central

    Li, Shujing; Ao, Xiang

    2013-01-01

    The circadian rhythm is an endogenous time keeping system shared by most organisms. The circadian clock is comprised of both peripheral oscillators in most organ tissues of the body and a central pacemaker located in the suprachiasmatic nucleus (SCN) of the central nervous system. The circadian rhythm is crucial in maintaining the normal physiology of the organism including, but not limited to, cell proliferation, cell cycle progression, and cellular metabolism; whereas disruption of the circadian rhythm is closely related to multi-tumorigenesis. In the past several years, studies from different fields have revealed that the genetic or functional disruption of the molecular circadian rhythm has been found in various cancers, such as breast, prostate, and ovarian. In this review, we will investigate and present an overview of the current research on the influence of circadian rhythm regulating proteins on breast cancer. PMID:23997531

  12. Daily Rhythms in Mosquitoes and Their Consequences for Malaria Transmission

    PubMed Central

    Rund, Samuel S. C.; O’Donnell, Aidan J.; Gentile, James E.; Reece, Sarah E.

    2016-01-01

    The 24-h day involves cycles in environmental factors that impact organismal fitness. This is thought to select for organisms to regulate their temporal biology accordingly, through circadian and diel rhythms. In addition to rhythms in abiotic factors (such as light and temperature), biotic factors, including ecological interactions, also follow daily cycles. How daily rhythms shape, and are shaped by, interactions between organisms is poorly understood. Here, we review an emerging area, namely the causes and consequences of daily rhythms in the interactions between vectors, their hosts and the parasites they transmit. We focus on mosquitoes, malaria parasites and vertebrate hosts, because this system offers the opportunity to integrate from genetic and molecular mechanisms to population dynamics and because disrupting rhythms offers a novel avenue for disease control. PMID:27089370

  13. Renal electrolyte circadian rhythms - Independence from feeding and activity patterns

    NASA Technical Reports Server (NTRS)

    Moore-Ede, M. C.; Herd, J. A.

    1977-01-01

    Experiments were conducted on six unanesthetized chair-acclimatized adult male squirrel monkeys (Saimiri sciureus) weighing 600-900 g to determine whether internal synchronization is the result of simple passive dependence of renal excretory rhythms on endogenous rhythms of those variable that influence electrolyte excretion such as dietary intake and muscular activity. Independence of the urinary rhythms from diurnal variations in feeding, drinking, and activity was secured by depriving the animals of food, water, and training them to perform a two-hourly schedule of feeding, drinking, and activity throughout day and night. Results indicate that the internal synchronization which is normally observed between the behavioral and urinary rhythms cannot be explained by any direct dependence of renal function on behavioral patterns. The most probable mechanism for circadian internal synchronization is that the various behavioral and renal rhythms are controlled by potentially independent separate oscillators which are normally kept in synchrony with one another.

  14. Circadian rhythms in the short-tailed shrew, Blarina brevicauda.

    PubMed

    Antipas, A J; Madison, D M; Ferraro, J S

    1990-08-01

    Circadian rhythms of wheel running and feeding were measured in the short-tailed shrew. Shrews were strongly nocturnal, and their activity rhythms entrained to both long-day (LD 16:8) and short-day (LD 6:18) photocycles. Under conditions of continuous light (LL) or darkness (DD), the activity rhythms free-ran with average periodicities of 25.1 hours and 24.1 hours, respectively. In LL the level of activity was depressed, and in some cases wheel running was completely inhibited. No significant sex differences were observed in the period or amplitude of the monitored circadian rhythms. All shrews fed throughout the day and night; however, unlike in previous reports, ultradian periods of feeding behavior were not found. The results are related to Aschoff's four observations for the effect of light on activity rhythms in nocturnal rodents. PMID:2255728

  15. Paroxysmal supraventricular tachycardia (PSVT)

    MedlinePlus

    PSVT; Supraventricular tachycardia; Abnormal heart rhythm - PSVT; Arrhythmia - PSVT; Rapid heart rate - PSVT; Fast heart rate - PSVT ... Normally, the chambers of the heart (atria and ventricles) contract in ... are caused by an electrical signal that begins in an area ...

  16. Digoxin Oral

    MedlinePlus

    ... to treat heart failure and abnormal heart rhythms (arrhythmias). It helps the heart work better and it ... have or have ever had thyroid problems, heart arrhythmias, cancer, or kidney disease.tell your doctor if ...

  17. The impact of yoga on atrial fibrillation: A review of The Yoga My Heart Study

    PubMed Central

    Deutsch, Steven Brent; Krivitsky, Eric Lawrence

    2015-01-01

    Atrial fibrillation is a common arrhythmia affecting thousands of individuals worldwide. It is a conduction disorder that causes the heart to beat irregularly and rapidly. There are a few medical approaches to manage this costly health care burden: antiarrhythmics to maintain normal sinus rhythm, beta blockers to achieve rate control while allowing atrial fibrillation to persist, and electro-physiologic intervention for rate and rhythm control. These treatments can be costly and are not without side effects. Yoga, an intervention that is available to people worldwide, has shown some promise in combating this widespread heart disorder. PMID:26702311

  18. Chronotype predicts positive affect rhythms measured by ecological momentary assessment.

    PubMed

    Miller, Megan A; Rothenberger, Scott D; Hasler, Brant P; Donofry, Shannon D; Wong, Patricia M; Manuck, Stephen B; Kamarck, Thomas W; Roecklein, Kathryn A

    2015-04-01

    Evening chronotype, a correlate of delayed circadian rhythms, is associated with depression. Altered positive affect (PA) rhythms may mediate the association between evening chronotype and depression severity. Consequently, a better understanding of the relationship between chronotype and PA may aid in understanding the etiology of depression. Recent studies have found that individuals with evening chronotype show delayed and blunted PA rhythms, although these studies are relatively limited in sample size, representativeness and number of daily affect measures. Further, published studies have not included how sleep timing changes on workday and non-workdays, or social jet lag (SJL) may contribute to the chronotype-PA rhythm link. Healthy non-depressed adults (n = 408) completed self-report affect and chronotype questionnaires. Subsequently, positive and negative affects were measured hourly while awake for at least two workdays and one non-workday by ecological momentary assessment (EMA). Sleep variables were collected via actigraphy and compared across chronotype groups. A cosinor variant of multilevel modeling was used to model individual and chronotype group rhythms and to calculate two variables: (1) amplitude of PA, or the absolute amount of daily variation from peak to trough during one period of the rhythm and (2) acrophase, or the time at which the peak amplitude of affect rhythms occurred. On workdays, individuals with evening chronotype had significantly lower PA amplitudes and later workday acrophase times than their morning type counterparts. In contrast to predictions, SJL was not found to be a mediator in the relationship between chronotype and PA rhythms. The association of chronotype and PA rhythms in healthy adults may suggest the importance of daily measurement of PA in depressed individuals and would be consistent with the hypothesis that evening chronotype may create vulnerability to depression via delayed and blunted PA rhythms. PMID

  19. Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.

    ERIC Educational Resources Information Center

    Fernald, Charles D.

    1980-01-01

    Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

  20. Cross-cultural influences on rhythm processing: reproduction, discrimination, and beat tapping

    PubMed Central

    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 culture of the participant and the culture of the rhythm. Specifically, we predicted that a participant’s ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than for unfamiliar rhythms. Moreover, there were differences between the two participant groups, and between the two types of rhythms, in the metrical level selected for beat tapping. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion

  1. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population

    PubMed Central

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-01-01

    Abstract The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China. This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated. A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19–61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 am in winter and at 2:00 am in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 pm to 8:00 am, except for 6:00 am, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05). The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  2. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population.

    PubMed

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-08-01

    The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China.This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated.A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19-61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 AM in winter and at 2:00 AM in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 PM to 8:00 AM, except for 6:00 AM, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05).The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  3. Abnormal human sex chromosome constitutions

    SciTech Connect

    1993-12-31

    Chapter 22, discusses abnormal human sex chromosome constitution. Aneuploidy of X chromosomes with a female phenotype, sex chromosome aneuploidy with a male phenotype, and various abnormalities in X chromosome behavior are described. 31 refs., 2 figs.

  4. Exercises to Improve Gait Abnormalities

    MedlinePlus

    ... Home About iChip Articles Directories Videos Resources Contact Exercises to Improve Gait Abnormalities Home » Article Categories » Exercise and Fitness Font Size: A A A A Exercises to Improve Gait Abnormalities Next Page The manner ...

  5. Interpersonal and social rhythm therapy: an intervention addressing rhythm dysregulation in bipolar disorder

    PubMed Central

    Frank, Ellen; Swartz, Holly A.; Boland, Elaine

    2007-01-01

    Bipolar disorder is characterized by frequent recurrences, often related to noncompliance with drug treatment, stressful life events, and disruptions in social rhythms. Interpersonal and social rhythm therapy (IPSRT) was designed to directly address these problem areas. This article discusses the circadian basis of IPSRT and the importance of stable daily routines in the maintenance of the euthymic state, as well as the two large controlled trials which empirically support this intervention. The authors discuss the advantages of IPSRT as an acute intervention, as well as a prophylactic treatment for both bipolar I and II disorder. Using a case example, the authors describe how IPSRT is implemented in a clinical setting, detailing the therapeutic methods and processes involved. PMID:17969869

  6. Building models for postmortem abnormalities in hippocampus of schizophrenics.

    PubMed

    Benes, Francine M

    2015-09-01

    Postmortem studies have suggested that there is abnormal GABAergic activity in the hippocampus in schizophrenia (SZ). In micro-dissected human hippocampal slices, a loss of interneurons and a compensatory upregulation of GABAA receptor binding activity on interneurons, but not PNs, has suggested that disinhibitory GABA-to-GABA connections are abnormal in stratum oriens (SO) of CA3/2, but not CA1, in schizophrenia. Abnormal expression changes in the expression of kainate receptor (KAR) subunits 5, 6 and 7, as well as an inwardly-rectifying hyperpolarization-activated cationic channel (Ih3; HCN3) may play important roles in regulating GABA cell activity at the SO CA3/2 locus. The exclusive neurons at this site are GABAergic interneurons; these cells also receive direct projections from the basolateral amygdala (BLA). When the BLA is stimulated by stereotaxic infusion of picrotoxin in rats, KARs influence axodendritic and presynaptic inhibitory mechanisms that regulate both inhibitory and disinhibitory interneurons in the SO-CA3/2 locus. The rat model described here was specifically developed to extend our understanding of these and other postmortem findings and has suggested that GABAergic abnormalities and possible disturbances in oscillatory rhythms may be related to a dysfunction of disinhibitory interneurons at the SO-CA3/2 site of schizophrenics. PMID:25749020

  7. Role of Circadian Rhythms in Potassium Homeostasis

    PubMed Central

    Gumz, Michelle L.; Rabinowitz, Lawrence

    2013-01-01

    It has been known for decades that urinary potassium excretion varies with a circadian pattern. In this review, we consider the historical evidence for this phenomenon and present an overview of recent developments in the field. Extensive evidence from the latter part of the last century clearly demonstrates that circadian potassium excretion does not depend on endogenous aldosterone. Of note is the recent discovery that the expression of several renal potassium transporters varies with a circadian pattern that appears to be consistent with substantial clinical data regarding daily fluctuations in urinary potassium levels. We propose the circadian clock mechanism as a key regulator of renal potassium transporters, and consequently renal potassium excretion. Further investigation into the mechanism of regulation of renal potassium transport by the circadian clock is warranted in order to increase our understanding of the clinical relevance of circadian rhythms to potassium homeostasis. PMID:23953800

  8. Copula-based analysis of rhythm

    NASA Astrophysics Data System (ADS)

    García, J. E.; González-López, V. A.; Viola, M. L. Lanfredi

    2016-06-01

    In this paper we establish stochastic profiles of the rhythm for three languages: English, Japanese and Spanish. We model the increase or decrease of the acoustical energy, collected into three bands coming from the acoustic signal. The number of parameters needed to specify a discrete multivariate Markov chain grows exponentially with the order and dimension of the chain. In this case the size of the database is not large enough for a consistent estimation of the model. We apply a strategy to estimate a multivariate process with an order greater than the order achieved using standard procedures. The new strategy consist on obtaining a partition of the state space which is constructed from a combination of the partitions corresponding to the three marginal processes, one for each band of energy, and the partition coming from to the multivariate Markov chain. Then, all the partitions are linked using a copula, in order to estimate the transition probabilities.

  9. Sensorimotor Rhythm Neurofeedback Enhances Golf Putting Performance.

    PubMed

    Cheng, Ming Yang; Huang, Chung Ju; Chang, Yu Kai; Koester, Dirk; Schack, Thomas; Hung, Tsung Min

    2015-12-01

    Sensorimotor rhythm (SMR) activity has been related to automaticity during skilled action execution. However, few studies have bridged the causal link between SMR activity and sports performance. This study investigated the effect of SMR neurofeedback training (SMR NFT) on golf putting performance. We hypothesized that preelite golfers would exhibit enhanced putting performance after SMR NFT. Sixteen preelite golfers were recruited and randomly assigned into either an SMR or a control group. Participants were asked to perform putting while electroencephalogram (EEG) was recorded, both before and after intervention. Our results showed that the SMR group performed more accurately when putting and exhibited greater SMR power than the control group after 8 intervention sessions. This study concludes that SMR NFT is effective for increasing SMR during action preparation and for enhancing golf putting performance. Moreover, greater SMR activity might be an EEG signature of improved attention processing, which induces superior putting performance. PMID:26866770

  10. Unstable periodic orbits in human cardiac rhythms

    NASA Astrophysics Data System (ADS)

    Narayanan, K.; Govindan, R. B.; Gopinathan, M. S.

    1998-04-01

    Unstable periodic orbits (UPOs) extracted from experimental electrocardiograph signals are reported for normal and pathological human cardiac rhythms. The periodicity and distribution of the orbits on the chaotic attractor are found to be indicative of the state of health of the cardiac system. The normal cardiac system is characterized by three to four UPOs with typical periodicities and intensities. However, pathological conditions such as premature ventricular contraction, atrio ventricular block, ventricular tachy arrhythmia, and ventricular fibrillation have UPOs whose periodicity and intensity distribution are quite distinct from those of the healthy cases and are characteristic of the pathological conditions. Eigenvalues and the largest positive Lyapunov exponent value for the UPOs are also reported. The UPOs are shown to be insensitive to the embedding dimension and the present UPO analysis is demonstrated to be reliable by the method of surrogate analysis.

  11. Cardiovascular rhythms in the 0.15-Hz band: common origin of identical phenomena in man and dog in the reticular formation of the brain stem?

    PubMed

    Perlitz, Volker; Lambertz, Manfred; Cotuk, Birol; Grebe, Reinhard; Vandenhouten, Ralf; Flatten, Guido; Petzold, Ernst Richard; Schmid-Schönbein, Holger; Langhorst, Peter

    2004-09-01

    Selected examples from experiments in humans and dogs with time series of reticular neurons, respiration, arterial blood pressure and cutaneous forehead blood content fluctuations were analysed using multiscaled time-frequency distribution, post-event-scan and pointwise transinformation. We found in both experiments a "0.15-Hz rhythm" exhibiting periods of spindle waves (increasing and decreasing amplitudes), phase synchronized with respiration at 1:2 and 1:1 integer number ratios. At times of wave-epochs and n:m phase synchronization, the 0.15-Hz rhythm appeared in heart rate and arterial blood pressure. As phase synchronization of the 0.15-Hz rhythm with respiration was established at a 1:1 integer number ratio, all cardiovascular-respiratory oscillations were synchronized at 0.15 Hz. Analysis of a canine experiment supplied evidence that the emergence of the 0.15-Hz rhythm and n:m phase synchronization appears to result from a decline in the level of the general activity of the organism associated with a decline in the level of activity of reticular neurons in the lower brainstem network. These findings corroborate the notion of the 0.15-Hz rhythm as a marker of the "trophotropic mode of operation" first introduced by W.R. Hess. PMID:15138824

  12. Heart CT scan

    MedlinePlus

    CAT scan - heart; Computed axial tomography scan - heart; Computed tomography scan - heart; Calcium scoring; Multi-detector CT scan - heart; Electron beam computed tomography - heart; Agaston score; Coronary calcium scan

  13. Coronary heart disease

    MedlinePlus

    Heart disease, Coronary heart disease, Coronary artery disease; Arteriosclerotic heart disease; CHD; CAD ... Coronary heart disease is the leading cause of death in the United States for men and women. Coronary heart ...

  14. Wine and heart health

    MedlinePlus

    Health and wine; Wine and heart disease; Preventing heart disease - wine; Preventing heart disease - alcohol ... more often just to lower your risk of heart disease. Heavier drinking can harm the heart and ...

  15. What Is Heart Failure?

    MedlinePlus

    ... page from the NHLBI on Twitter. What Is Heart Failure? Heart failure is a condition in which the heart can' ... force. Some people have both problems. The term "heart failure" doesn't mean that your heart has stopped ...

  16. Hearts Wish.

    ERIC Educational Resources Information Center

    Jones, Lethonee A.

    1989-01-01

    Investigates characteristics and themes in 102 drawings by sexually abused children. Themes of the drawings included genitalia, the absence of specific body parts, phallic symbols, inappropriate smiles, distorted body images, kinetic activity, prominent hands and fingers, and hearts. (RJC)

  17. Heart palpitations

    MedlinePlus

    Heart palpitations can be due to: Anxiety, stress, panic attack, or fear Caffeine intake Nicotine intake Cocaine or other illegal drugs Diet pills Exercise Fever However, some palpitations are due ...

  18. Heart Failure

    MedlinePlus

    ... together. About Rise Above HF Rise Above Heart Failure seeks to increase the dialogue about HF and improve the lives of people affected by the condition through awareness, education and support. Through the initiative, AHA strives to ...

  19. Heart Transplant

    MedlinePlus

    ... Doctors remove the patient's heart by transecting the aorta , the main pulmonary artery and the superior and ... sewing together the recipient and donor vena cavae, aorta, pulmonary artery and left atrium. In patients with ...

  20. Heart MRI

    MedlinePlus

    ... an imaging method that uses powerful magnets and radio waves to create pictures of the heart. It does ... radiation involved in MRI. The magnetic fields and radio waves used during the scan have not been shown ...

  1. Heart Attack

    MedlinePlus

    ... lower “bad” cholesterol (also called LDL, or low-density lipoprotein) levels and may help increase “good” cholesterol (also called HDL, or high-density lipoprotein). If you have had a heart attack, ...

  2. Heart pacemaker

    MedlinePlus

    ... may not get enough oxygen. Symptoms may be light-headedness, tiredness, fainting spells, and shortness of breath. Some pacemakers can be used to stop a heart rate that is too fast ( tachycardia ) ...

  3. Heart transplant

    MedlinePlus

    ... have symptoms. You must take drugs that prevent transplant rejection for the rest of your life. You will ... heart transplant. The main problem, as with other transplants, is rejection. If rejection can be controlled, survival increases to ...

  4. Circadian rhythms, sleep, and performance in space

    NASA Technical Reports Server (NTRS)

    Mallis, M. M.; DeRoshia, C. W.

    2005-01-01

    Maintaining optimal alertness and neurobehavioral functioning during space operations is critical to enable the National Aeronautics and Space Administration's (NASA's) vision "to extend humanity's reach to the Moon, Mars and beyond" to become a reality. Field data have demonstrated that sleep times and performance of crewmembers can be compromised by extended duty days, irregular work schedules, high workload, and varying environmental factors. This paper documents evidence of significant sleep loss and disruption of circadian rhythms in astronauts and associated performance decrements during several space missions, which demonstrates the need to develop effective countermeasures. Both sleep and circadian disruptions have been identified in the Behavioral Health and Performance (BH&P) area and the Advanced Human Support Technology (AHST) area of NASA's Bioastronautics Critical Path Roadmap. Such disruptions could have serious consequences on the effectiveness, health, and safety of astronaut crews, thus reducing the safety margin and increasing the chances of an accident or incident. These decrements oftentimes can be difficult to detect and counter effectively in restrictive operational environments. NASA is focusing research on the development of optimal sleep/wake schedules and countermeasure timing and application to help mitigate the cumulative effects of sleep and circadian disruption and enhance operational performance. Investing research in humans is one of NASA's building blocks that will allow for both short- and long-duration space missions and help NASA in developing approaches to manage and overcome the human limitations of space travel. In addition to reviewing the current state of knowledge concerning sleep and circadian disruptions during space operations, this paper provides an overview of NASA's broad research goals. Also, NASA-funded research, designed to evaluate the relationships between sleep quality, circadian rhythm stability, and

  5. Circadian rhythms, sleep, and performance in space.

    PubMed

    Mallis, M M; DeRoshia, C W

    2005-06-01

    Maintaining optimal alertness and neurobehavioral functioning during space operations is critical to enable the National Aeronautics and Space Administration's (NASA's) vision "to extend humanity's reach to the Moon, Mars and beyond" to become a reality. Field data have demonstrated that sleep times and performance of crewmembers can be compromised by extended duty days, irregular work schedules, high workload, and varying environmental factors. This paper documents evidence of significant sleep loss and disruption of circadian rhythms in astronauts and associated performance decrements during several space missions, which demonstrates the need to develop effective countermeasures. Both sleep and circadian disruptions have been identified in the Behavioral Health and Performance (BH&P) area and the Advanced Human Support Technology (AHST) area of NASA's Bioastronautics Critical Path Roadmap. Such disruptions could have serious consequences on the effectiveness, health, and safety of astronaut crews, thus reducing the safety margin and increasing the chances of an accident or incident. These decrements oftentimes can be difficult to detect and counter effectively in restrictive operational environments. NASA is focusing research on the development of optimal sleep/wake schedules and countermeasure timing and application to help mitigate the cumulative effects of sleep and circadian disruption and enhance operational performance. Investing research in humans is one of NASA's building blocks that will allow for both short- and long-duration space missions and help NASA in developing approaches to manage and overcome the human limitations of space travel. In addition to reviewing the current state of knowledge concerning sleep and circadian disruptions during space operations, this paper provides an overview of NASA's broad research goals. Also, NASA-funded research, designed to evaluate the relationships between sleep quality, circadian rhythm stability, and

  6. Adverse Pregnancy Outcomes after Abnormal First Trimester Screening for Aneuploidy

    PubMed Central

    Goetzl, Laura

    2010-01-01

    Women with abnormal first trimester screening but with a normal karyotype are at risk for adverse pregnancy outcomes. A nuchal translucency >3.5mm is associated with an increased risk of subsequent pregnancy loss, fetal infection, fetal heart abnormalities and other structural abnormalities. Abnormal first trimester analytes are also associated with adverse pregnancy outcomes but the predictive value is less impressive. As a single marker, PAPP-A <1st%ile has a good predictive value for subsequent fetal growth restriction. Women with PAPP-A<5th%ile should undergo subsequent risk assessment with routine MSAFP screening with the possible addition of uterine artery PI assessment in the midtrimester. PMID:20638576

  7. Spirometric abnormalities among welders

    SciTech Connect

    Rastogi, S.K.; Gupta, B.N.; Husain, T.; Mathur, N.; Srivastava, S. )

    1991-10-01

    A group of manual welders age group 13-60 years having a mean exposure period of 12.4 {plus minus} 1.12 years were subjected to spirometry to evaluate the prevalence of spirometric abnormalities. The welders showed a significantly higher prevalence of respiratory impairment than that observed among the unexposed controls as a result of exposure to welding gases which comprised fine particles of lead, zinc, chromium, and manganese. This occurred despite the lower concentration of the pollutants at the work place. In the expose group, the smoking welders showed a prevalence of respiratory impairment significantly higher than that observed in the nonsmoking welders. The results of the pulmonary function tests showed a predominantly restrictive type of pulmonary impairment followed by a mixed ventilatory defect among the welders. The effect of age on pulmonary impairment was not discernible. Welders exposed for over 10 years showed a prevalence of respiratory abnormalities significantly higher than those exposed for less than 10 years. Smoking also had a contributory role.

  8. Prediction of maintenance of sinus rhythm after cardioversion of atrial fibrillation by analysis of serial signal-averaged P waves.

    PubMed

    Stafford, P J; Kamalvand, K; Tan, K; Vincent, R; Sulke, N

    1998-07-01

    After cardioversion from atrial fibrillation (AF) many patients develop early recurrence of the arrhythmia. While these patients may be appropriate for immediate prophylaxis against AF recurrence their identification at the time of cardioversion is not possible. Since the signal-averaged P wave (SAPW) is abnormal in individuals with atrial arrhythmia, we assessed its utility for predicting early AF recurrence after cardioversion. Seventy-five cardioversions in 31 patients were evaluated. The mean age was 59 (range 28-79) years; 26 were male. Fifty-eight cardioversions were internal using low energy biphasic DC shocks delivered via electrodes placed in the right atrial appendage and coronary sinus. P wave specific signal averaging was performed at 3 and 24 hours after each cardioversion to estimate filtered P wave duration and energy from 20, 40, and 60 to 150 Hz. Follow-up was by regular clinic visits and transtelephonic ECG monitoring. Early recurrence of AF (prospectively defined as sinus rhythm duration < 1 week) occurred after 30 cardioversions. No differences were found in any P wave variable measured at 3 hours between these cardioversions and those that resulted in a longer duration of sinus rhythm. Paired 3- and 24-hour signal-averaged data were available in 47 cardioversions. There were significant falls in P wave energy from 3 to 24 hours after 31 cardioversions that resulted in sinus rhythm for > 1 week, (P40: 3 hours 11.2 [+/- 1.5] micro V2.s, 24 hours 8.6 [+/- 1.2] micro V2.s, P < 0.001), but not following the 16 after which AF returned within 1 week (P40: 3 hours 9.0 [+/- 1.2] micro V2.s, 24 hours 8.5 [+/- 1.2 micro V2.s, P = NS). A fall in P40 of > 25% had a positive predictive accuracy for maintenance of sinus rhythm of 87%; negative predictive accuracy was only 37%. Similar falls in P wave energy occurred after cardioversions that resulted in longer term (> 4 weeks) sinus rhythm, but not in those that did not. However, the predictive accuracy of a

  9. [The kidney and circadian rhythms: a whole new world?].

    PubMed

    Manfredini, Roberto; Sasso, Ferdinando Carlo; Pala, Marco; De Giorgi, Alfredo; Fabbian, Fabio

    2013-01-01

    Chronobiology is a branch of biomedical sciences devoted to the study of biological rhythms. Biological rhythms exist at any level of living organisms and, according to their cycle length, may be divided into three main types: circadian, ultradian, and infradian rhythms. Circadian rhythms are the most commonly and widely studied. The principal circadian clock is located in the suprachiasmatic nucleus of the hypothalamus, and is supposed to regulate peripheral clocks via neurohumoral modulation. Circadian clocks have been identified within almost all mammalian cell types, and circadian clock genes seem to be essential for cardiovascular health. Disturbance of the renal circadian rhythms is increasingly recognized as a risk factor for hypertension, polyuria, and other diseases and may contribute to renal fibrosis. The origin of these rhythms has been attributed to the reactive response of the kidney to circadian changes in volume and/or in the composition of extracellular fluids regulated by rest/activity and feeding/fasting cycles. However, most of the renal excretory rhythms persist for long periods of time, even in the absence of periodic environmental cues. These observations led to the hypothesis of the existence of a self-sustained mechanism, enabling the kidney to anticipate various predictable circadian challenges to homeostasis. The molecular basis of this mechanism remained unknown until the recent discovery of the mammalian circadian clock, comprising a system of autoregulatory transcriptional/translational feedback loops, which have also been found in the kidney. PMID:24403200

  10. Vasoactive intestinal polypeptide entrains circadian rhythms in astrocytes.

    PubMed

    Marpegan, Luciano; Krall, Thomas J; Herzog, Erik D

    2009-04-01

    Many mammalian cell types show daily rhythms in gene expression driven by a circadian pacemaker. For example, cultured astrocytes display circadian rhythms in Period1 and Period2 expression. It is not known, however, how or which intercellular factors synchronize and sustain rhythmicity in astrocytes. Because astrocytes are highly sensitive to vasoactive intestinal polypeptide (VIP), a neuropeptide released by neurons and important for the coordination of daily cycling, the authors hypothesized that VIP entrains circadian rhythms in astrocytes. They used astrocyte cultures derived from knock-in mice containing a bioluminescent reporter of PERIOD2 (PER2) protein, to assess the effects of VIP on the rhythmic properties of astrocytes. VIP induced a dose-dependent increase in the peak-to-trough amplitude of the ensemble rhythms of PER2 expression with maximal effects near 100 nM VIP and threshold values between 0.1 and 1 nM. VIP also induced dose- and phase-dependent shifts in PER2 rhythms and daily VIP administration entrained bioluminescence rhythms of astrocytes to a predicted phase angle. This is the first demonstration that a neuropeptide can entrain glial cells to a phase predicted by a phase-response curve. The authors conclude that VIP potently entrains astrocytes in vitro and is a candidate for coordinating daily rhythms among glia in the brain. PMID:19346450

  11. Vasoactive intestinal polypeptide entrains circadian rhythms in astrocytes

    PubMed Central

    Marpegan, Luciano; Krall, Thomas J.; Herzog, Erik D.

    2009-01-01

    Many mammalian cell types show daily rhythms in gene expression driven by a circadian pacemaker. For example, cultured astrocytes display circadian rhythms in Period1 and Period2 expression. It is not known, however, how or which intercellular factors synchronize and sustain rhythmicity in astrocytes. Because astrocytes are highly sensitive to vasoactive intestinal polypeptide (VIP), a neuropeptide released by neurons and important for the coordination of daily cycling, we hypothesized that VIP entrains circadian rhythms in astrocytes. We used astrocyte cultures derived from knock-in mice containing a bioluminescent reporter of PERIOD2 (PER2) protein, to assess the effects of VIP on the rhythmic properties of astrocytes. VIP induced a dose-dependent increase in the peak-to-trough amplitude of the ensemble rhythms of PER2 expression with maximal effects near 100nM VIP and threshold values between 0.1 and 1 nM. VIP also induced dose- and phase-dependent shifts in PER2 rhythms and daily VIP administration entrained bioluminescence rhythms of astrocytes to a predicted phase angle. This is the first demonstration that a neuropeptide can entrain glial cells to a phase predicted by a phase response curve. We conclude that VIP potently entrains astrocytes in vitro and is a candidate for coordinating daily rhythms among glia in the brain. PMID:19346450

  12. Neural Networks for Beat Perception in Musical Rhythm

    PubMed Central

    Large, Edward W.; Herrera, Jorge A.; Velasco, Marc J.

    2015-01-01

    Entrainment of cortical rhythms to acoustic rhythms has been hypothesized to be the neural correlate of pulse and meter perception in music. Dynamic attending theory first proposed synchronization of endogenous perceptual rhythms nearly 40 years ago, but only recently has the pivotal role of neural synchrony been demonstrated. Significant progress has since been made in understanding the role of neural oscillations and the neural structures that support synchronized responses to musical rhythm. Synchronized neural activity has been observed in auditory and motor networks, and has been linked with attentional allocation and movement coordination. Here we describe a neurodynamic model that shows how self-organization of oscillations in interacting sensory and motor networks could be responsible for the formation of the pulse percept in complex rhythms. In a pulse synchronization study, we test the model's key prediction that pulse can be perceived at a frequency for which no spectral energy is present in the amplitude envelope of the acoustic rhythm. The result shows that participants perceive the pulse at the theoretically predicted frequency. This model is one of the few consistent with neurophysiological evidence on the role of neural oscillation, and it explains a phenomenon that other computational models fail to explain. Because it is based on a canonical model, the predictions hold for an entire family of dynamical systems, not only a specific one. Thus, this model provides a theoretical link between oscillatory neurodynamics and the induction of pulse and meter in musical rhythm. PMID:26635549

  13. Heterogeneity induces rhythms of weakly coupled circadian neurons.

    PubMed

    Gu, Changgui; Liang, Xiaoming; Yang, Huijie; Rohling, Jos H T

    2016-01-01

    The main clock located in the suprachiasmatic nucleus (SCN) regulates circadian rhythms in mammals. The SCN is composed of approximately twenty thousand heterogeneous self-oscillating neurons, that have intrinsic periods varying from 22 h to 28 h. They are coupled through neurotransmitters and neuropeptides to form a network and output a uniform periodic rhythm. Previous studies found that the heterogeneity of the neurons leads to attenuation of the circadian rhythm with strong cellular coupling. In the present study, we investigate the heterogeneity of the neurons and of the network in the condition of constant darkness. Interestingly, we found that the heterogeneity of weakly coupled neurons enables them to oscillate and strengthen the circadian rhythm. In addition, we found that the period of the SCN network increases with the increase of the degree of heterogeneity. As the network heterogeneity does not change the dynamics of the rhythm, our study shows that the heterogeneity of the neurons is vitally important for rhythm generation in weakly coupled systems, such as the SCN, and it provides a new method to strengthen the circadian rhythm, as well as an alternative explanation for differences in free running periods between species in the absence of the daily cycle. PMID:26898574

  14. Heterogeneity induces rhythms of weakly coupled circadian neurons

    PubMed Central

    Gu, Changgui; Liang, Xiaoming; Yang, Huijie; Rohling, Jos H. T.

    2016-01-01

    The main clock located in the suprachiasmatic nucleus (SCN) regulates circadian rhythms in mammals. The SCN is composed of approximately twenty thousand heterogeneous self-oscillating neurons, that have intrinsic periods varying from 22 h to 28 h. They are coupled through neurotransmitters and neuropeptides to form a network and output a uniform periodic rhythm. Previous studies found that the heterogeneity of the neurons leads to attenuation of the circadian rhythm with strong cellular coupling. In the present study, we investigate the heterogeneity of the neurons and of the network in the condition of constant darkness. Interestingly, we found that the heterogeneity of weakly coupled neurons enables them to oscillate and strengthen the circadian rhythm. In addition, we found that the period of the SCN network increases with the increase of the degree of heterogeneity. As the network heterogeneity does not change the dynamics of the rhythm, our study shows that the heterogeneity of the neurons is vitally important for rhythm generation in weakly coupled systems, such as the SCN, and it provides a new method to strengthen the circadian rhythm, as well as an alternative explanation for differences in free running periods between species in the absence of the daily cycle. PMID:26898574

  15. Neural Responses to Complex Auditory Rhythms: The Role of Attending

    PubMed Central

    Chapin, Heather L.; Zanto, Theodore; Jantzen, Kelly J.; Kelso, Scott J. A.; Steinberg, Fred; Large, Edward W.

    2010-01-01

    The aim of this study was to explore the role of attention in pulse and meter perception using complex rhythms. We used a selective attention paradigm in which participants attended to either a complex auditory rhythm or a visually presented word list. Performance on a reproduction task was used to gauge whether participants were attending to the appropriate stimulus. We hypothesized that attention to complex rhythms – which contain no energy at the pulse frequency – would lead to activations in motor areas involved in pulse perception. Moreover, because multiple repetitions of a complex rhythm are needed to perceive a pulse, activations in pulse-related areas would be seen only after sufficient time had elapsed for pulse perception to develop. Selective attention was also expected to modulate activity in sensory areas specific to the modality. We found that selective attention to rhythms led to increased BOLD responses in basal ganglia, and basal ganglia activity was observed only after the rhythms had cycled enough times for a stable pulse percept to develop. These observations suggest that attention is needed to recruit motor activations associated with the perception of pulse in complex rhythms. Moreover, attention to the auditory stimulus enhanced activity in an attentional sensory network including primary auditory cortex, insula, anterior cingulate, and prefrontal cortex, and suppressed activity in sensory areas associated with attending to the visual stimulus. PMID:21833279

  16. Neural Networks for Beat Perception in Musical Rhythm.

    PubMed

    Large, Edward W; Herrera, Jorge A; Velasco, Marc J

    2015-01-01

    Entrainment of cortical rhythms to acoustic rhythms has been hypothesized to be the neural correlate of pulse and meter perception in music. Dynamic attending theory first proposed synchronization of endogenous perceptual rhythms nearly 40 years ago, but only recently has the pivotal role of neural synchrony been demonstrated. Significant progress has since been made in understanding the role of neural oscillations and the neural structures that support synchronized responses to musical rhythm. Synchronized neural activity has been observed in auditory and motor networks, and has been linked with attentional allocation and movement coordination. Here we describe a neurodynamic model that shows how self-organization of oscillations in interacting sensory and motor networks could be responsible for the formation of the pulse percept in complex rhythms. In a pulse synchronization study, we test the model's key prediction that pulse can be perceived at a frequency for which no spectral energy is present in the amplitude envelope of the acoustic rhythm. The result shows that participants perceive the pulse at the theoretically predicted frequency. This model is one of the few consistent with neurophysiological evidence on the role of neural oscillation, and it explains a phenomenon that other computational models fail to explain. Because it is based on a canonical model, the predictions hold for an entire family of dynamical systems, not only a specific one. Thus, this model provides a theoretical link between oscillatory neurodynamics and the induction of pulse and meter in musical rhythm. PMID:26635549

  17. Endogenous thermoregulatory rhythms of squirrel monkeys in thermoneutrality and cold

    NASA Technical Reports Server (NTRS)

    Robinson, E. L.; Fuller, C. A.

    1999-01-01

    Whole body heat production (HP) and heat loss (HL) were examined to determine if the free-running circadian rhythm in body temperature (Tb) results from coordinated changes in HP and HL rhythms in thermoneutrality (27 degrees C) as well as mild cold (17 degrees C). Squirrel monkey metabolism (n = 6) was monitored by both indirect and direct calorimetry, with telemetered measurement of Tb and activity. Feeding was also measured. Rhythms of HP, HL, and conductance were tightly coupled with the circadian Tb rhythm at both ambient temperatures (TA). At 17 degrees C, increased HP compensated for higher HL at all phases of the Tb rhythm, resulting in only minor changes to Tb. Parallel compensatory changes of HP and HL were seen at all rhythm phases at both TA. Similar time courses of Tb, HP, and HL in their respective rhythms and the relative stability of Tb during both active and rest periods suggest action of the circadian timing system on Tb set point.

  18. Inverse Correlation between Heart Rate Variability and Heart Rate Demonstrated by Linear and Nonlinear Analysis.

    PubMed

    Kazmi, Syed Zaki Hassan; Zhang, Henggui; Aziz, Wajid; Monfredi, Oliver; Abbas, Syed Ali; Shah, Saeed Arif; Kazmi, Syeda Sobia Hassan; Butt, Wasi Haider

    2016-01-01

    The dynamical fluctuations in the rhythms of biological systems provide valuable information about the underlying functioning of these systems. During the past few decades analysis of cardiac function based on the heart rate variability (HRV; variation in R wave to R wave intervals) has attracted great attention, resulting in more than 17000-publications (PubMed list). However, it is still controversial about the underling mechanisms of HRV. In this study, we performed both linear (time domain and frequency domain) and nonlinear analysis of HRV data acquired from humans and animals to identify the relationship between HRV and heart rate (HR). The HRV data consists of the following groups: (a) human normal sinus rhythm (n = 72); (b) human congestive heart failure (n = 44); (c) rabbit sinoatrial node cells (SANC; n = 67); (d) conscious rat (n = 11). In both human and animal data at variant pathological conditions, both linear and nonlinear analysis techniques showed an inverse correlation between HRV and HR, supporting the concept that HRV is dependent on HR, and therefore, HRV cannot be used in an ordinary manner to analyse autonomic nerve activity of a heart. PMID:27336907

  19. Inverse Correlation between Heart Rate Variability and Heart Rate Demonstrated by Linear and Nonlinear Analysis

    PubMed Central

    Zhang, Henggui; Aziz, Wajid; Monfredi, Oliver; Abbas, Syed Ali; Shah, Saeed Arif; Kazmi, Syeda Sobia Hassan; Butt, Wasi Haider

    2016-01-01

    The dynamical fluctuations in the rhythms of biological systems provide valuable information about the underlying functioning of these systems. During the past few decades analysis of cardiac function based on the heart rate variability (HRV; variation in R wave to R wave intervals) has attracted great attention, resulting in more than 17000-publications (PubMed list). However, it is still controversial about the underling mechanisms of HRV. In this study, we performed both linear (time domain and frequency domain) and nonlinear analysis of HRV data acquired from humans and animals to identify the relationship between HRV and heart rate (HR). The HRV data consists of the following groups: (a) human normal sinus rhythm (n = 72); (b) human congestive heart failure (n = 44); (c) rabbit sinoatrial node cells (SANC; n = 67); (d) conscious rat (n = 11). In both human and animal data at variant pathological conditions, both linear and nonlinear analysis techniques showed an inverse correlation between HRV and HR, supporting the concept that HRV is dependent on HR, and therefore, HRV cannot be used in an ordinary manner to analyse autonomic nerve activity of a heart. PMID:27336907

  20. Modelling the heart as a communication system

    PubMed Central

    Ashikaga, Hiroshi; Aguilar-Rodríguez, José; Gorsky, Shai; Lusczek, Elizabeth; Marquitti, Flávia Maria Darcie; Thompson, Brian; Wu, Degang; Garland, Joshua

    2015-01-01

    Electrical communication between cardiomyocytes can be perturbed during arrhythmia, but these perturbations are not captured by conventional electrocardiographic metrics. We developed a theoretical framework to quantify electrical communication using information theory metrics in two-dimensional cell lattice models of cardiac excitation propagation. The time series generated by each cell was coarse-grained to 1 when excited or 0 when resting. The Shannon entropy for each cell was calculated from the time series during four clinically important heart rhythms: normal heartbeat, anatomical reentry, spiral reentry and multiple reentry. We also used mutual information to perform spatial profiling of communication during these cardiac arrhythmias. We found that information sharing between cells was spatially heterogeneous. In addition, cardiac arrhythmia significantly impacted information sharing within the heart. Entropy localized the path of the drifting core of spiral reentry, which could be an optimal target of therapeutic ablation. We conclude that information theory metrics can quantitatively assess electrical communication among cardiomyocytes. The traditional concept of the heart as a functional syncytium sharing electrical information cannot predict altered entropy and information sharing during complex arrhythmia. Information theory metrics may find clinical application in the identification of rhythm-specific treatments which are currently unmet by traditional electrocardiographic techniques. PMID:25740854