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Sample records for abnormal cardiac rhythms

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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.

  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. 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

  10. [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

  11. 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. ...

  12. 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

  13. 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

  14. Determination of myocardial energetic output for cardiac rhythm pacing.

    PubMed

    Herman, Dalibor; Prevorovská, Svetlana; Marsík, Frantisek

    2007-12-01

    This research is aimed to the determination of the changes in the cardiac energetic output for three different modes of cardiac rhythm pacing. The clinical investigation of thirteen patients with the permanent dual-chamber pacemaker implantation was carried out. The patients were taken to echocardiography examination conducted by way of three pacing modes (AAI, VVI and DDD). The myocardial energetic parameters-the stroke work index (SWI) and the myocardial oxygen consumption (MVO2) are not directly measurable, however, their values can be determined using the numerical model of the human cardiovascular system. The 24-segment hemodynamical model (pulsating type) of the human cardiovascular system was used for the numerical simulation of the changes of myocardial workload for cardiac rhythm pacing. The model was fitted by well-measurable parameters for each patient. The calculated parameters were compared using the two-tailed Student's test. The differences of SWI and MVO2 between the modes AAI and VVI and the modes DDD and VVI are statistically significant (P<0.05). On the other hand, the hemodynamic effects for the stimulation modes DDD and AAI are almost identical, i.e. the differences are statistically insignificant (P>0.05). PMID:18080208

  15. 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.

  16. 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

  17. [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

  18. 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

  19. 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

    by atropine in both tetraplegic and healthy subjects, these rhythms reflect in an important way rhythmic firing of vagal cardiac motoneurones.

  20. A Retrospective Study of Congenital Cardiac Abnormality Associated with Scoliosis

    PubMed Central

    Ucpunar, Hanifi; Sevencan, Ahmet; Balioglu, Mehmet Bulent; Albayrak, Akif; Polat, Veli

    2016-01-01

    Study Design Retrospective study. Purpose To identify the incidence of congenital cardiac abnormalities in patients who had scoliosis and underwent surgical treatment for scoliosis. Overview of Literature Congenital and idiopathic scoliosis (IS) are associated with cardiac abnormalities. We sought to establish and compare the incidence of congenital cardiac abnormalities in patients with idiopathic and congenital scoliosis (CS) who underwent surgical treatment for scoliosis. Methods Ninety consecutive scoliosis patients, who underwent surgical correction of scoliosis, were classified as CS (55 patients, 28 female [51%]) and IS (35 patients, 21 female [60%]). The complete data of the patients, including medical records, plain radiograph and transthoracic echocardiography were retrospectively assessed. Results We found that mitral valve prolapse was the most common cardiac abnormality in both patients with IS (nine patients, 26%) and CS (13 patients, 24%). Other congenital cardiac abnormalities were atrial septal aneurysm (23% of IS patients, 18% of CS patients), pulmonary insufficiency (20% of IS patients, 4% of CS patients), aortic insufficiency (17% of IS patients), atrial septal defect (11% of IS patients, 13% of CS patients), patent foramen ovale (15% of CS patients), dextrocardia (4% of CS patients), bicuspid aortic valve (3% of IS patients), aortic stenosis (2% of CS patients), ventricular septal defect (2% of CS patients), and cardiomyopathy (2% of CS patients). Conclusions We determined the increased incidence of congenital cardiac abnormalities among patients with congenital and IS. Mitral valve prolapse appeared to be the most prevalent congenital cardiac abnormality in both groups. PMID:27114761

  1. 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

  2. Cardiac sodium channel regulator MOG1 regulates cardiac morphogenesis and rhythm

    PubMed Central

    Zhou, Juan; Wang, Longfei; Zuo, Mengxia; Wang, Xiaojing; Ahmed, Abu Shufian Ishtiaq; Chen, Qiuyun; Wang, Qing K.

    2016-01-01

    MOG1 was initially identified as a protein that interacts with the small GTPase Ran involved in transport of macromolecules into and out of the nucleus. In addition, we have established that MOG1 interacts with the cardiac sodium channel Nav1.5 and regulates cell surface trafficking of Nav1.5. Here we used zebrafish as a model system to study the in vivo physiological role of MOG1. Knockdown of mog1 expression in zebrafish embryos significantly decreased the heart rate (HR). Consistently, the HR increases in embryos with over-expression of human MOG1. Compared with wild type MOG1 or control EGFP, mutant MOG1 with mutation E83D associated with Brugada syndrome significantly decreases the HR. Interestingly, knockdown of mog1 resulted in abnormal cardiac looping during embryogenesis. Mechanistically, knockdown of mog1 decreases expression of hcn4 involved in the regulation of the HR, and reduces expression of nkx2.5, gata4 and hand2 involved in cardiac morphogenesis. These data for the first time revealed a novel role that MOG1, a nucleocytoplasmic transport protein, plays in cardiac physiology and development. PMID:26903377

  3. 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.

  4. Resolution of abnormal cardiac MRI T2 signal following immune suppression for cardiac sarcoidosis.

    PubMed

    Crouser, Elliott D; Ruden, Emily; Julian, Mark W; Raman, Subha V

    2016-08-01

    Cardiac MR (CMR) with late gadolinium enhancement is commonly used to detect cardiac damage in the setting of cardiac sarcoidosis. The addition of T2 mapping to CMR was recently shown to enhance cardiac sarcoidosis detection and correlates with increased cardiac arrhythmia risk. This study was conducted to determine if CMR T2 abnormalities and related arrhythmias are reversible following immune suppression therapy. A retrospective study of subjects with cardiac sarcoidosis with abnormal T2 signal on baseline CMR and a follow-up CMR study at least 4 months later was conducted at The Ohio State University from 2011 to 2015. Immune suppression treated participants had a significant reduction in peak myocardial T2 value (70.0±5.5 vs 59.2±6.1 ms, pretreatment vs post-treatment; p=0.017), and 83% of immune suppression treated subjects had objective improvement in cardiac arrhythmias. Two subjects who had received inadequate immune suppression treatment experienced progression of cardiac sarcoidosis. This report indicates that abnormal CMR T2 signal represents an acute inflammatory manifestation of cardiac sarcoidosis that is potentially reversible with adequate immune suppression therapy. PMID:27354042

  5. Cardiac abnormalities in end stage renal failure and anaemia.

    PubMed Central

    Morris, K P; Skinner, J R; Wren, C; Hunter, S; Coulthard, M G

    1993-01-01

    Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities. Images PMID:8323332

  6. Using Reduced Interference Distribution to Analyze Abnormal Cardiac Signal

    NASA Astrophysics Data System (ADS)

    Mousa, Allam; Saleem, Rashid

    2011-05-01

    Due to the non-stationary, multicomponent nature of biomedical signals, the use of time-frequency analysis can be inevitable for these signals. The choice and selection of the proper Time-Frequency Distribution (TFD) that can reveal the exact multicomponent structure of biological signals is vital in many applications, including the diagnosis of medical abnormalities. In this paper, the instantaneous frequency techniques using two distribution functions are applied for analysis of biological signals. These distributions are the Wigner-Ville Distribution and the Bessel Distribution. The simulation performed on normaland abnormal cardiac signals show that the Bessel Distribution can clearly detect the QRS complexes. However, Wigner-Ville Distribution was able to detect the QRS complexes in the normal signa, but fails to detect these complexes in the abnormal cardiac signal.

  7. Evidence Based Review: Risk of Cardiac Rhythm Problems During Spaceflight

    NASA Technical Reports Server (NTRS)

    Platts, Steven H.; Stenger, Michael B.; Phillips, Tiffany R.; Brown, Angela K.; Arzeno, Natalia M.; Levine, Benjamin; Summers, Richard

    2009-01-01

    Very little research has systematically evaluated the prevalence (or potential risk) of cardiac arrhythmias during space flight. There are several observational reports of non life-threatening but potentially concerning arrhythmias. At least two potential risk factors for arrhythmias have been reported either during or immediately after space flight: cardiac atrophy and a prolonged QTc interval. The potential severity of the mission impact of a serious arrhythmia requires that a systematic evaluation be conducted of the risk of arrhythmia due to space flight.

  8. 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

  9. Cardiac ultrasonography in structural abnormalities and arrhythmias. Recognition and treatment.

    PubMed Central

    Brook, M M; Silverman, N H; Villegas, M

    1993-01-01

    Fetal cardiac ultrasonography has become an important tool in the evaluation of fetuses at risk for cardiac anomalies. It can both guide prenatal treatment and assist the management and timing of delivery. We recommend that a fetal echocardiogram be done when there is a family history of congenital heart disease; maternal disease that may affect the fetus; a history of maternal drug use, either therapeutic or illegal; evidence of other fetal abnormalities; or evidence of fetal hydrops. The optimal timing of evaluation is 18 to 22 weeks' gestation. An entire range of structural cardiac defects can be visualized prenatally, including atrioventricular septal defect, ventricular septal defect, cardiomyopathy, ventricular outlet obstruction, and complex cardiac defects. The outcome for a fetus with a recognized abnormality is unfavourable, with less than 50% surviving the neonatal period. Fetal cardiac arrhythmias are also a common occurrence, 15% in the series described here. Premature atrial or ventricular contractions are most commonly seen and usually require no treatment. Supraventricular tachycardia can result in hydrops and require in utero treatment to prevent fetal demise. Complete heart block, particularly in association with structural heart disease, has a poor prognosis for fetal survival. Images PMID:8236970

  10. Cardiac and other abnormalities in the sudden infant death syndrome.

    PubMed

    Naeye, R L; Whalen, P; Ryser, M; Fisher, R

    1976-01-01

    Many victims of the sudden infant death syndrome (SIDS) have abnormally heavy cardiac right ventricles. The degree of this abnormality is directly proportional to: a) the mass of muscle about small pulmonary arteries, b) the amount of brown fat retention about adrenal glands, and c) the presence of hepatic erythropoiesis. The pulmonary arterial abnormality is probably the result of chronic alveolar hypoventilation, while brown fat retention and hepatic erythropoiesis are likely consequences of chronic hypoxemia. These abnormalities are found in both SIDS victims who die with and those who die without mild respiratory tract infections. However, there are some differences between the two SIDS groups. Infected victims die at an older age and have smaller thymus glands and larger spleens; there is a greater proportion of males in the infected victims than in the noninfected victims. PMID:1247080

  11. 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

  12. 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.

  13. Cardiac Abnormalities in Youth with Obesity and Type 2 Diabetes.

    PubMed

    Bacha, Fida; Gidding, Samuel S

    2016-07-01

    Childhood obesity has been linked to cardiovascular disease (CVD) risk in adulthood. Of great concern is the expected increase in the population's CVD burden in relation to childhood obesity. This is compounded by the risk related to chronic hyperglycemia exposure in youth with type 2 diabetes. We herein provide an overview of the spectrum of early cardiovascular disease manifestation in youth with obesity and type 2 diabetes, in particular abnormalities in cardiac structure and function. Cardiac remodeling and adverse target organ damage is already evident in the pediatric age group in children with obesity and type 2 diabetes. This supports the importance of intensifying obesity prevention efforts and early intervention to treat comorbidities of obesity in the pediatric age group to prevent cardiac events in early adulthood. PMID:27168062

  14. 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

  15. 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

    purpose for cardiorespiratory coupling is the biggest barrier for recognizing its significance. Cardiorespiratory coupling has only a small effect on the efficiency of gas exchange; rather, we propose that cardiorespiratory control system may act as weakly coupled oscillator to maintain rhythms within a bounded variability. PMID:24746049

  16. Cardiac repolarization abnormalities and increased sympathetic activity in scleroderma.

    PubMed Central

    Ciftci, Orcun; Onat, Ahmet Mesut; Yavuz, Bunyamin; Akdogan, Ali; Aytemir, Kudret; Tokgozoglu, Lale; Sahiner, Levent; Deniz, Ali; Ureten, Kemal; Kizilca, Guler; Calguneri, Meral; Oto, Ali

    2007-01-01

    BACKGROUND: Cardiac involvement in scleroderma is a poor prognostic sign and is usually underdiagnosed, particularly in asymptomatic patient. This paper focuses on QT dynamicity and heart rate variability (HRV) in patients with scleroderma and controls in an attempt to investigate the cardiac autonomic system and ventricular repolarization. METHODS: Sixty patients with scleroderma and 30 age- and sex-matched healthy controls who had no cardiovascular risk factors were included in this study. All patients and the controls underwent a 24-hour holter recording as well as a transthoracic echocardiography. HRV and QT dynamicity parameters were calculated. RESULTS: In HRV analysis, autonomic balance was changed in favor of the sympathetic system in patients with diffuse scleroderma. In QT dynamicity analysis, QT/RR slopes were significantly steeper in patients with diffuse scleroderma compared to patients with limited scleroderma and controls (QTapex/RR: 0.24 +/- 0.16, 0.15 +/- 0.03, 0.14 +/- 0.03 respectively p < 0.001; QTend/RR: 0.26 +/- 0.17, 0.14 +/- 0.04, 0.13 +/- 0.05, respectively p < 0.001). CONCLUSIONS: Patients with diffuse scleroderma may have asymptomatic cardiac repolarization abnormalities and autonomic dysfunction. Our results may indicate that QT dynamicity and HRV can be useful noninvasive methods that may detect impaired state of autonomic balance and cardiac repolarization in patients with diffuse scleroderma. PMID:17393947

  17. Pericardial Fat and Echocardiographic Measures of Cardiac Abnormalities

    PubMed Central

    Liu, Jiankang; Fox, Caroline S.; Hickson, DeMarc A.; May, Warren L.; Ding, Jingzhong; Carr, J. Jeffery; Taylor, Herman A.

    2011-01-01

    OBJECTIVE Pericardial adipose tissue (PAT), a regional fat depot adjacent to the myocardium, may mediate the complex relation between obesity and cardiac left ventricular (LV) abnormalities. We sought to evaluate the association of PAT with echocardiographic measures of LV abnormalities in the Jackson Heart Study (JHS). RESEARCH DESIGN AND METHODS A total of 1,414 African Americans (35% men; mean age 58 years) from the JHS underwent computed tomographic assessment of PAT and abdominal visceral adipose tissue (VAT) from 2007 to 2009 and echocardiography examination between 2000 and 2004. Echocardiographic measures of left atrial (LA) internal diameter, LV mass, LV ejection fraction (LVEF), and E-wave velocity-to-A-wave velocity ratio (E/A ratio) were examined in relation to PAT, VAT, BMI, and waist circumference (WC). RESULTS All adiposity measures were positively correlated with LA diameter and LV mass and negatively correlated with E/A ratio (P = 0.02 to 0.0001) and were not with LVEF (P = 0.36–0.61). In women, per 1-SD increment of PAT, we observed association with higher LV mass (9.0 ± 1.7 gm, P = 0.0001) and LA diameter (1.0 ± 0.1 mm, P = 0.0001). However, the magnitude of the association between PAT and cardiac measures was similar compared with VAT (P = 0.65 [LV mass]; P = 0.26 [LA diameter]) and was smallercompared with BMI (P = 0.002 [LV mass]; P = 0.01 [LA diameter]) and WC (P = 0.009 [LA diameter]). CONCLUSIONS PAT is correlated with echocardiographic measures of cardiac LV abnormalities, but the association is not stronger than other adiposity measures. PMID:21228247

  18. Chromosomal abnormalities among children born with conotruncal cardiac defects

    PubMed Central

    Lammer, Edward J.; Chak, Jacqueline S.; Iovannisci, David M.; Schultz, Kathleen; Osoegawa, Kazutoyo; Yang, Wei; Carmichael, Suzan L.; Shaw, Gary M.

    2010-01-01

    BACKGROUND Conotruncal heart defects comprise 25%-30% of non-syndromic congenital heart defects. This study describes the frequency of chromosome abnormalities and microdeletion 22q11 associated with conotruncal heart malformations. METHODS From a population base of 974,579 infants/fetuses delivered, 622 Californian infants/fetuses were ascertained with a defect of aortico-pulmonary septation. Infants whose primary cardiac defect was tetralogy of Fallot (n=296) or D-transposition of the great vessels (n=189) were screened for microdeletions of 22q11. RESULTS Fourteen (2.3%) of the 622 infants/fetuses had chromosomal abnormalities. Thirty infants, 10% of those whose primary defect was tetralogy of Fallot, had chromosome 22q11 microdeletions. Right aortic arch, abnormal branching patterns of the major arteries arising from the thoracic aorta, and pulmonary artery abnormalities were observed more frequently in these children. CONCLUSIONS We found an unusual number of infants with an extra sex chromosome and a conotruncal defect. Infants with tetralogy of Fallot due to 22q11 microdeletion showed more associated vascular anomalies than infants with tetralogy but no 22q11 microdeletion. Although these associated vascular anomalies provide clues as to which infants with tetralogy of Fallot are more likely to carry the microdeletion, the overall risk of 10% among all infants with tetralogy of Fallot warrants chromosome analysis and FISH testing routinely. PMID:19067405

  19. Associations between Kidney Function and Subclinical Cardiac Abnormalities in CKD

    PubMed Central

    Hsu, Chi-yuan; Li, Yongmei; Mishra, Rakesh K.; Keane, Martin; Rosas, Sylvia E.; Dries, Daniel; Xie, Dawei; Chen, Jing; He, Jiang; Anderson, Amanda; Go, Alan S.; Shlipak, Michael G.

    2012-01-01

    Heart failure is a common consequence of CKD, and it portends high risk for mortality. However, among patients without known heart failure, the associations of different stages of estimated GFR (eGFR) with changes in cardiac structure and function are not well described. Here, we performed a cross-sectional analysis to study these associations among 3487 participants of the Chronic Renal Insufficiency Cohort Study. We estimated GFR using cystatin C. The prevalence of left ventricular hypertrophy (LVH) assessed by echocardiography was 32%, 48%, 57%, and 75% for eGFR categories ≥60, 45–59, 30–44, and <30 ml/min per 1.73 m2, respectively. In fully adjusted multivariable analyses, subjects with eGFR levels of <30 ml/min per 1.73 m2 had twofold higher odds of LVH (OR=2.20, 95% CI=1.40–3.40; P<0.001) relative to subjects with eGFR≥60 ml/min per 1.73 m2. This reduction in kidney function also significantly associated with abnormal LV geometry but not diastolic or systolic dysfunction. An eGFR of 30–44 ml/min per 1.73 m2 also significantly associated with LVH and abnormal LV geometry compared with eGFR≥60 ml/min per 1.73 m2. In summary, in this large CKD cohort, reduced kidney function associated with abnormal cardiac structure. We did not detect significant associations between kidney function and systolic or diastolic function after adjusting for potential confounding variables. PMID:22935481

  20. Electrocardiographic abnormalities and cardiac arrhythmias in structural brain lesions.

    PubMed

    Katsanos, Aristeidis H; Korantzopoulos, Panagiotis; Tsivgoulis, Georgios; Kyritsis, Athanassios P; Kosmidou, Maria; Giannopoulos, Sotirios

    2013-07-31

    Cardiac arrhythmias and electrocardiographic abnormalities are frequently observed after acute cerebrovascular events. The precise mechanism that leads to the development of these arrhythmias is still uncertain, though increasing evidence suggests that it is mainly due to autonomic nervous system dysregulation. In massive brain lesions sympathetic predominance and parasympathetic withdrawal during the first 72 h are associated with the occurrence of severe secondary complications in the first week. Right insular cortex lesions are also related with sympathetic overactivation and with a higher incidence of electrocardiographic abnormalities, mostly QT prolongation, in patients with ischemic stroke. Additionally, female sex and hypokalemia are independent risk factors for severe prolongation of the QT interval which subsequently results in malignant arrhythmias and poor outcome. The prognostic value of repolarization changes commonly seen after aneurysmal subarachnoid hemorrhage, such as ST segment, T wave, and U wave abnormalities, still remains controversial. In patients with traumatic brain injury both intracranial hypertension and cerebral hypoperfusion correlate with low heart rate variability and increased mortality. Given that there are no firm guidelines for the prevention or treatment of the arrhythmias that appear after cerebral incidents this review aims to highlight important issues on this topic. Selected patients with the aforementioned risk factors could benefit from electrocardiographic monitoring, reassessment of the medications that prolong QTc interval, and administration of antiadrenergic agents. Further research is required in order to validate these assumptions and to establish specific therapeutic strategies. PMID:22809542

  1. Diurnal Cortisol Rhythm Is Associated With Adverse Cardiac Events and Mortality in Coronary Artery Bypass Patients

    PubMed Central

    Kidd, Tara; Poole, Lydia; Leigh, Elizabeth; Jahangiri, Marjan; Steptoe, Andrew

    2015-01-01

    Purpose: There is growing evidence that the hypothalamic-pituitary-adrenal axis plays a role in the progression of cardiovascular disease. We examined the relationship between diurnal cortisol rhythm and adverse events in patients undergoing coronary artery bypass graft (CABG) surgery. We hypothesized that a flatter presurgical diurnal cortisol slope would be associated with higher rates of adverse cardiac events and death in the years following the CABG procedure. Methods: Repeated measures of saliva were taken over the day from 250 CABG patients 1 month before surgery to assess diurnal cortisol slope and overall output (area under the curve). Long-term clinical outcomes were occurrence of a major adverse cardiac event (MACE) and death, and were collected up to 2.68 (SD = 0.40) years after surgery. Cox proportional hazard models were used to determine relationships between presurgical cortisol and clinical outcomes. EuroSCORE, chronic illness burden, and whether or not the patient had undergone cardiopulmonary bypass were included as covariates in the models. Results: Diurnal cortisol slope predicted the occurrence of MACE or death after surgery (hazard ratio = 0.73; 95% confidence interval = 0.56–0.96; P = .023). Patients with a steeper slope were at reduced risk of adverse outcomes. This association was driven by changes in both waking and evening cortisol levels. Conclusion: These results provide evidence for a link between diurnal cortisol rhythm and recovery after CABG. Measuring diurnal cortisol slope before surgery may help to identify those patients at risk of adverse outcomes in the years after the procedure. PMID:26305622

  2. 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

  3. [The utility of remote monitoring in the follow-up of patients with cardiac rhythm management devices].

    PubMed

    Mäkelä, Timo; Uusimaa, Paavo; Koivisto, Ulla-Maija; Raatikainen, Pekka

    2009-01-01

    The launch of Internet-based remote monitoring is an important milestone in the management of patients with cardiac rhythm management (CRM) devices. A remote monitoring system consists of a portable patient monitor, a central database in a secure server, and a password-protected website, where clinicians can view and analyse patient's device data. The latest CRM devices support automatic wireless data transmission from the device to the patient monitor, making the system even more user-friendly. In Finland the longest experience with remote monitoring of cardiac rhythm management devices is in the Oulu University Hospital. According to our experience remote monitoring provides a tremendous convenience for patients and clinicians and reduces the cost of follow-up. PMID:19938409

  4. Abnormal Cardiac Autonomic Regulation in Mice Lacking ASIC3

    PubMed Central

    Cheng, Ching-Feng; Kuo, Terry B. J.; Chen, Wei-Nan

    2014-01-01

    Integration of sympathetic and parasympathetic outflow is essential in maintaining normal cardiac autonomic function. Recent studies demonstrate that acid-sensing ion channel 3 (ASIC3) is a sensitive acid sensor for cardiac ischemia and prolonged mild acidification can open ASIC3 and evoke a sustained inward current that fires action potentials in cardiac sensory neurons. However, the physiological role of ASIC3 in cardiac autonomic regulation is not known. In this study, we elucidate the role of ASIC3 in cardiac autonomic function using Asic3−/− mice. Asic3−/− mice showed normal baseline heart rate and lower blood pressure as compared with their wild-type littermates. Heart rate variability analyses revealed imbalanced autonomic regulation, with decreased sympathetic function. Furthermore, Asic3−/− mice demonstrated a blunted response to isoproterenol-induced cardiac tachycardia and prolonged duration to recover to baseline heart rate. Moreover, quantitative RT-PCR analysis of gene expression in sensory ganglia and heart revealed that no gene compensation for muscarinic acetylcholines receptors and beta-adrenalin receptors were found in Asic3−/− mice. In summary, we unraveled an important role of ASIC3 in regulating cardiac autonomic function, whereby loss of ASIC3 alters the normal physiological response to ischemic stimuli, which reveals new implications for therapy in autonomic nervous system-related cardiovascular diseases. PMID:24804235

  5. Abnormal cardiac autonomic regulation in mice lacking ASIC3.

    PubMed

    Cheng, Ching-Feng; Kuo, Terry B J; Chen, Wei-Nan; Lin, Chao-Chieh; Chen, Chih-Cheng

    2014-01-01

    Integration of sympathetic and parasympathetic outflow is essential in maintaining normal cardiac autonomic function. Recent studies demonstrate that acid-sensing ion channel 3 (ASIC3) is a sensitive acid sensor for cardiac ischemia and prolonged mild acidification can open ASIC3 and evoke a sustained inward current that fires action potentials in cardiac sensory neurons. However, the physiological role of ASIC3 in cardiac autonomic regulation is not known. In this study, we elucidate the role of ASIC3 in cardiac autonomic function using Asic3(-/-) mice. Asic3(-/-) mice showed normal baseline heart rate and lower blood pressure as compared with their wild-type littermates. Heart rate variability analyses revealed imbalanced autonomic regulation, with decreased sympathetic function. Furthermore, Asic3(-/-) mice demonstrated a blunted response to isoproterenol-induced cardiac tachycardia and prolonged duration to recover to baseline heart rate. Moreover, quantitative RT-PCR analysis of gene expression in sensory ganglia and heart revealed that no gene compensation for muscarinic acetylcholines receptors and beta-adrenalin receptors were found in Asic3(-/-) mice. In summary, we unraveled an important role of ASIC3 in regulating cardiac autonomic function, whereby loss of ASIC3 alters the normal physiological response to ischemic stimuli, which reveals new implications for therapy in autonomic nervous system-related cardiovascular diseases. PMID:24804235

  6. [Clinico-diagnostic and expert characteristics of noncoronary cardiac rhythm disorders in state aviation pilots].

    PubMed

    Nagovitsyn, A V; Ardashev, V N; Voronkov, Yu I

    2013-01-01

    Structure and prevalence of various forms of noncoronary heart diseases (NCHD) and cardiac rhythm disorders (CRD) in state aviation pilots, as well as rates of ensuing grounding were studied. The total of 220 NCHD and 100 essentially healthy pilots were examined. Cardiovascular clinical and functional investigations consisted of physical examination, ECG, dispersion mapping (DM ECG), provocative tests and other techniques used for pilots' certification. Effectiveness of the clinical and instrumental methods of diagnosing arrhythmias was evaluated. CRD presence was verified by Holter monitoring. Extrasystoles prevalence was recorded in NCHD pilots; clinically significant forms of the diseases were commonly detected in pilots with chronic infections of the tonsils. In addition, radiodiagnostics of the immune status was applied to confirm the role of infection and immunology factor. DM ECG screening for differentiation between the norm and pathology was found useful in detecting early metabolic shifts and CVS functional evaluation. These results provided the basis for guidelines concerning medical expertise of pilots with noncoronary arrhythmias. PMID:24032165

  7. Echocardiographic abnormalities in the assessment of cardiac organ damage in never-treated hypertensive patients.

    PubMed

    Milan, Alberto; Avenatti, Eleonora; Puglisi, Elisabetta; Abram, Sara; Magnino, Corrado; Naso, Diego; Tosello, Francesco; Fabbri, Ambra; Vairo, Alessandro; Mulatero, Paolo; Rabbia, Franco; Veglio, Franco

    2012-01-01

    Hypertension-related cardiac organ damage, other than left ventricular (LV) hypertrophy (LVH), has been described: in particular, concentric remodeling, LV diastolic dysfunction (DD), and left atrial (LA) enlargement are significantly associated with cardiovascular morbility and mortality in different populations. This study evaluated the prevalence of these latter morphofunctional abnormalities, in never-treated essential hypertensive patients and the role of such a serial assessment of hypertensive cardiac damage in improving cardiovascular risk stratification in these patients. A total of 100 never-treated essential hypertensive subjects underwent a complete clinical and echocardiographic evaluation. Left ventricular morphology, systolic and diastolic function, and LA dimension (linear and volume) were evaluated by echocardiography. Left ventricular hypertrophy was present in 14% of the patients, whereas concentric remodeling was present in 25% of the subjects. Among patients free from LV morphology abnormalities, the most frequent abnormality was LA enlargement (global prevalence 57%); the percentage of patients with at least one parameter consistent with DD was 22% in the entire population, but DD was present as the only cardiac abnormality in 1% of our patient. Left atrial volume indexed for body surface area was the most sensitive parameter in identifying hypertension-related cardiac modification. The global prevalence of cardiac alteration reached 73% in never-treated hypertensive patients. Left ventricular remodeling and LA enlargement evaluation may grant a better assessment of cardiac organ damage and cardiovascular risk stratification of hypertensive patients without evidence of LVH after routine examination. PMID:22738434

  8. Unusual association between cardiac, skeletal, urogenital and renal abnormalities.

    PubMed

    Goryaeva, Maria; Sykes, Mark Christopher; Lau, Benjamin; West, Simon

    2016-01-01

    We present a 33-year-old woman with an array of congenital abnormalities. She has been diagnosed with polycystic kidney disease (PCKD) with no detectable mutations in PKD1 or PKD2, spina bifida occulta, thoracic skeletal abnormalities, a uterus didelphys and a patent foramen ovale (PFO). There are several associations reported in the literature that include abnormalities similar to the patient's, but none describe her presentation in its entirety. The MURCS association is characterised by (MU)llerian duct aplasia, (R)enal dysplasia and (C)ervical (S)omite anomalies and goes some way in explaining these condition. Patients with both MURCS and PCKD have not been described in current literature. Through this report, we hope to bring a potential diagnosis to light and provide the patient with an improved understanding of her health. PMID:27402585

  9. Cardiac, skeletal, and ocular abnormalities in patients with Marfan's syndrome and in their relatives. Comparison with the cardiac abnormalities in patients with kyphoscoliosis.

    PubMed Central

    Bruno, L; Tredici, S; Mangiavacchi, M; Colombo, V; Mazzotta, G F; Sirtori, C R

    1984-01-01

    Polygraphic (including apexcardiograms and carotid pulse tracings) and M mode echocardiographic examinations were carried out in 34 symptomatic patients with Marfan's syndrome; similar studies were performed in 32 relatives and in 34 young patients with kyphoscoliotic disease. The purpose of these investigations was to determine the association between cardiac and oculoskeletal abnormalities and to identify specific patterns of disease with a poor prognosis. Polygraphic tests showed significant changes in all patients with Marfan's syndrome: 74% showed the apical systolic click and murmur of mitral valve prolapse; 48% had the diastolic murmur of aortic regurgitation; isolated mitral valve prolapse was found in 52%, 26% had isolated aortic regurgitation, and 22% had a combination of the two. Echocardiographic changes were also found in all patients: 79% had aortic root dilatation; 48% fluttering of the anterior mitral leaflet; 79% mitral valve prolapse, mostly pansystolic; 34% both mitral prolapse and aortic root dilatation; and 34% left ventricular dilatation. The severities of the cardiac and oculoskeletal abnormalities were not correlated. The high prevalence of mitral valve prolapse found in these patients, which did not vary with age or sex, was also present in their relatives: mitral prolapse was present in 38% and aortic dilatation, with or without regurgitation, in 14%. Four of the relatives had clearcut Marfan's syndrome, and at least four others a forme fruste. The metacarpal index was abnormal in 41% of the relatives; ocular abnormalities were rare. In kyphoscoliotic patients only an increase in the prevalence of mitral prolapse (18.2% in women, none in men) was found. These findings underline a complex pattern of association between cardiac, ocular, and skeletal abnormalities in patients with Marfan's syndrome and confirm an appreciable inheritability of several of the markers of the disease. Images PMID:6691872

  10. 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

  11. Abnormal Myocardial Blood Flow Reserve Observed in Cardiac Amyloidosis

    PubMed Central

    Nel, Karen; Senior, Roxy; Greaves, Kim

    2016-01-01

    We performed real-time myocardial contrast echocardiography on a patient with cardiac amyloidosis and previous normal coronary angiography presenting with atypical chest pain to assess myocardial blood flow reserve (MBFR). Myocardial contrast echocardiography was performed and flash microbubble destruction and replenishment analysis was used to calculate myocardial blood flow. Dipyridamole was used to achieve hyperemia. MBFR was derived from the ratio of peak myocardial blood flow at hyperemia and rest. The results show a marked reduction in MBFR in our patient. Previous reports of luminal obstruction of intramyocardial rather than epicardial vessels by amyloid deposition may be causing microvascular dysfunction. PMID:27081447

  12. 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%.

  13. 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

  14. 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

  15. Emergency dispatch process and patient outcome in bystander-witnessed out-of-hospital cardiac arrest with a shockable rhythm

    PubMed Central

    Silfvast, Tom O.; Jäntti, T. Helena; Kuisma, Markku J.; Kurola, Jouni O.

    2015-01-01

    Objective To describe the dispatch process for out-of-hospital cardiac arrest (OHCA) in bystander-witnessed patients with initial shockable rhythm, and to evaluate whether recognition of OHCA by the emergency medical dispatcher (EMD) has an effect on the outcome. Methods This study was part of the FINNRESUSCI study focusing on the epidemiology and outcome of OHCA in Finland. Witnessed [not by Emergency Medical Service (EMS)] OHCA patients with initial shockable rhythm in the southern and the eastern parts of Finland during a 6-month period from March 1 to August 31 2010, were electronically collected from eight dispatch centres and from paper case reports filled out by EMS crews. Results Of the 164 patients, 82.3% (n=135) were correctly recognized by the EMD as cardiac arrests. The majority of all calls (90.7%) were dispatched within 2 min. Patients were more likely to survive and be discharged from the hospital if the EMS response time was within 8 min (P<0.001). Telephone-guided cardiopulmonary resuscitation (T-CPR) was given in 53 cases (32.3%). Overall survival to hospital discharge was 43.4% (n=71). Survival to hospital discharge was 44.4% (n=60) when the EMD recognized OHCA and 37.9% (n=11) when OHCA was not recognized. The difference was not statistically significant (P=0.521). Conclusion The rate of recognition of cardiac arrest by EMD was high, but EMD recognition did not affect the outcome. The survival rate was high in both groups. Recognized cardiac arrest patients received bystander CPR more frequently than those for whom OHCA remained unrecognized. PMID:24809817

  16. Electrocardiographic T Wave Abnormalities and the Risk of Sudden Cardiac Death: The Finnish Perspective.

    PubMed

    Tikkanen, Jani T; Kenttä, Tuomas; Porthan, Kimmo; Huikuri, Heikki V; Junttila, M Juhani

    2015-11-01

    The identification of patients at risk for sudden cardiac death (SCD) is still a significant challenge to clinicians and scientists. Noninvasive identification of high-risk patients has been of great interest, and several ventricular depolarization and repolarization abnormalities in the standard 12-lead electrocardiogram (ECG) have been associated with increased vulnerability to lethal ventricular arrhythmias. Several benign and pathological conditions can induce changes in repolarization detected as alteration of the ST segment or T wave. Changes in the ST segment and T waves can be early markers of an underlying cardiovascular disease, and even minor ST-T abnormalities have predicted reduced survival and increased risk of SCD in the adult population. In this review, we will discuss the current knowledge of the SCD risk with standard 12-lead ECG T wave abnormalities in the general population, and possible T wave changes in various cardiac conditions predisposing to SCD. PMID:26391699

  17. 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

  18. Detection of Cardiac Abnormalities from Multilead ECG using Multiscale Phase Alternation Features.

    PubMed

    Tripathy, R K; Dandapat, S

    2016-06-01

    The cardiac activities such as the depolarization and the relaxation of atria and ventricles are observed in electrocardiogram (ECG). The changes in the morphological features of ECG are the symptoms of particular heart pathology. It is a cumbersome task for medical experts to visually identify any subtle changes in the morphological features during 24 hours of ECG recording. Therefore, the automated analysis of ECG signal is a need for accurate detection of cardiac abnormalities. In this paper, a novel method for automated detection of cardiac abnormalities from multilead ECG is proposed. The method uses multiscale phase alternation (PA) features of multilead ECG and two classifiers, k-nearest neighbor (KNN) and fuzzy KNN for classification of bundle branch block (BBB), myocardial infarction (MI), heart muscle defect (HMD) and healthy control (HC). The dual tree complex wavelet transform (DTCWT) is used to decompose the ECG signal of each lead into complex wavelet coefficients at different scales. The phase of the complex wavelet coefficients is computed and the PA values at each wavelet scale are used as features for detection and classification of cardiac abnormalities. A publicly available multilead ECG database (PTB database) is used for testing of the proposed method. The experimental results show that, the proposed multiscale PA features and the fuzzy KNN classifier have better performance for detection of cardiac abnormalities with sensitivity values of 78.12 %, 80.90 % and 94.31 % for BBB, HMD and MI classes. The sensitivity value of proposed method for MI class is compared with the state-of-art techniques from multilead ECG. PMID:27118009

  19. Abnormal Calcium Handling and Exaggerated Cardiac Dysfunction in Mice with Defective Vitamin D Signaling

    PubMed Central

    Choudhury, Sangita; Bae, Soochan; Ke, Qingen; Lee, Ji Yoo; Singh, Sylvia S.; St-Arnaud, René; del Monte, Federica; Kang, Peter M.

    2014-01-01

    Aim Altered vitamin D signaling is associated with cardiac dysfunction, but the pathogenic mechanism is not clearly understood. We examine the mechanism and the role of vitamin D signaling in the development of cardiac dysfunction. Methods and Results We analyzed 1α-hydroxylase (1α-OHase) knockout (1α-OHase−/−) mice, which lack 1α-OH enzymes that convert the inactive form to hormonally active form of vitamin D. 1α-OHase−/− mice showed modest cardiac hypertrophy at baseline. Induction of pressure overload by transverse aortic constriction (TAC) demonstrated exaggerated cardiac dysfunction in 1α-OHase−/− mice compared to their WT littermates with a significant increase in fibrosis and expression of inflammatory cytokines. Analysis of calcium (Ca2+) transient demonstrated profound Ca2+ handling abnormalities in 1α-OHase−/− mouse cardiomyocytes (CMs), and treatment with paricalcitol (PC), an activated vitamin D3 analog, significantly attenuated defective Ca2+ handling in 1α-OHase−/− CMs. We further delineated the effect of vitamin D deficiency condition to TAC by first correcting the vitamin D deficiency in 1α-OHase−/− mice, followed then by either a daily maintenance dose of vitamin D or vehicle (to achieve vitamin D deficiency) at the time of sham or TAC. In mice treated with vitamin D, there was a significant attenuation of TAC-induced cardiac hypertrophy, interstitial fibrosis, inflammatory markers, Ca2+ handling abnormalities and cardiac function compared to the vehicle treated animals. Conclusions Our results provide insight into the mechanism of cardiac dysfunction, which is associated with severely defective Ca2+ handling and defective vitamin D signaling in 1α-OHase−/− mice. PMID:25268137

  20. 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

  1. Early administration of epinephrine (adrenaline) in patients with cardiac arrest with initial shockable rhythm in hospital: propensity score matched analysis

    PubMed Central

    Andersen, Lars W; Kurth, Tobias; Chase, Maureen; Berg, Katherine M; Cocchi, Michael N; Callaway, Clifton

    2016-01-01

    Objectives To evaluate whether patients who experience cardiac arrest in hospital receive epinephrine (adrenaline) within the two minutes after the first defibrillation (contrary to American Heart Association guidelines) and to evaluate the association between early administration of epinephrine and outcomes in this population. Design Prospective observational cohort study. Setting Analysis of data from the Get With The Guidelines-Resuscitation registry, which includes data from more than 300 hospitals in the United States. Participants Adults in hospital who experienced cardiac arrest with an initial shockable rhythm, including patients who had a first defibrillation within two minutes of the cardiac arrest and who remained in a shockable rhythm after defibrillation. Intervention Epinephrine given within two minutes after the first defibrillation. Main outcome measures Survival to hospital discharge. Secondary outcomes included return of spontaneous circulation and survival to hospital discharge with a good functional outcome. A propensity score was calculated for the receipt of epinephrine within two minutes after the first defibrillation, based on multiple characteristics of patients, events, and hospitals. Patients who received epinephrine at either zero, one, or two minutes after the first defibrillation were then matched on the propensity score with patients who were “at risk” of receiving epinephrine within the same minute but who did not receive it. Results 2978patients were matched on the propensity score, and the groups were well balanced. 1510 (51%) patients received epinephrine within two minutes after the first defibrillation, which is contrary to current American Heart Association guidelines. Epinephrine given within the first two minutes after the first defibrillation was associated with decreased odds of survival in the propensity score matched analysis (odds ratio 0.70, 95% confidence interval 0.59 to 0.82; P<0.001). Early epinephrine

  2. 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

  3. 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

  4. An interoperable system for automated diagnosis of cardiac abnormalities from electrocardiogram data.

    PubMed

    Tinnakornsrisuphap, Thidarat; Billo, Richard E

    2015-03-01

    Electrocardiogram (ECG) data are stored and analyzed in different formats, devices, and computer platforms. As a result, ECG data from different monitoring devices cannot be displayed unless the user has access to the proprietary software of each particular device. This research describes an ontology and encoding for representation of ECG data that allows open exchange and display of ECG data in a web browser. The ontology is based on the Health Level Seven (HL7) medical device communication standard. It integrates ECG waveform data, HL7 standard ECG data descriptions, and cardiac diagnosis rules, providing a capability to both represent ECG waveforms as well as perform automated diagnosis of 37 different cardiac abnormalities. The ECG ontology is encoded in XML, thus allowing ECG data from any digital ECG device that maps to it to be displayed in a general-purpose Internet browser. An experiment was conducted to test the interoperability of the system (ability to openly share ECG data without error in a web browser) and also to assess the accuracy of the diagnosis model. Results showed 100% interoperability using 276 ECG data files and 93% accuracy in diagnosis of abnormal cardiac conditions. PMID:24808416

  5. Cardiac conduction abnormalities and Stokes-Adams attacks in myotonic dystrophy.

    PubMed Central

    Noel, C.; Gagnon, R. M.

    1978-01-01

    Myotonic dystrophy is a well known cause of cardiomyopathy. While various cardiac conduction abnormalities have been described in patients with myotonic dystrophy, so far only sporadic cases of Stokes-Adams attacks have been reported. Of 27 patients with this disease various conduction disturbances were detected in 17 (63%), 5 of whom presented with Stokes-Adams attacks and were found to have intracardiac conduction defects. The prognosis in four of the five patients was greatly improved with permanent pacemaker implantation. Images FIG. 1 FIG. 2 PMID:657033

  6. 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

  7. Evaluation of a novel pulsatile extracorporeal life support system synchronized to the cardiac cycle: effect of rhythm changes on hemodynamic performance.

    PubMed

    Patel, Sunil; Wang, Shigang; Pauliks, Linda; Chang, Dennis; Clark, Joseph B; Kunselman, Allen R; Ündar, Akif

    2015-01-01

    Arrhythmias are a frequent complication during extracorporeal life support (ECLS). A new ECLS system can provide pulsatile flow synchronized to the patient's intrinsic cardiac cycle based upon the R wave of the electrocardiogram (ECG). It is unclear how the occurrence of arrhythmias may alter the hemodynamic performance of the system. This in vitro study evaluated the effect of simulated arrhythmias on hemodynamics during R wave-triggered pulsatile ECLS. The ECLS circuit with an i-cor diagonal pump and iLA membrane ventilator was primed with whole blood at room temperature. Flow and pressure data were collected at 2.5 and 4 L/min for each condition using a customized data acquisition system. Pulsatile ECLS flow was R wave synchronized to an ECG simulator using 1:1, 1:2, and 1:3 assist ratios. Conditions tested included sinus rhythm at 45 and 90 bpm, supraventricular tachycardia (SVT), ventricular tachycardia (VT), and irregular rhythms such as ventricular fibrillation. Pulsatile mode was successfully triggered by ECG signals of normal sinus rhythm, SVT, VT, atrial fibrillation, atrial flutter, and ventricular bigeminy with assist ratios 1:1, 1:2, and 1:3. Regular rhythm at 90 bpm generated the best surplus hemodynamic energy (SHE). For SVT and VT, an assist ratio of 1:2 resulted in maximum pulsatile flow waveforms with optimal SHE at 2.5 L/min flow rate. At 4 L/min, SHE declined and the pressure drop increased independent of arrhythmia condition. Irregular rhythms still produced adequate pulsatile wave forms at lower pulsatile frequency. This study demonstrated the feasibility of generating pulsatile ECLS flow with the novel ECG-synchronized i-cor system during various simulated rhythms. The optimal rate for pulsatile flow was 90 bpm. During irregular rhythms, the lower pulsatile frequency was the more reliable synchronization mode for generating pulsatile flow. PMID:25626581

  8. [Twenty-four hour automatic recording of blood pressure and cardiac rhythm in patients with borderline hypertension].

    PubMed

    Cybulska, I; Popławska, W; Niegowska, J; Makowiecka-Cieśla, M; Kabat, M; Borowiecka, E; Sznajderman, M

    1989-01-01

    The aim of the study was to evaluate the usefulness of 24-hour automatic recording of blood pressure and cardiac rhythm in patients with borderline hypertension. The study was performed in 50 patients aged 38.8 +/- 13.1 using the Del Mar Avionics device. Mean time of recordings was 21.3 hours, and the mean number of blood pressure measurements per one patient was 52.4. Great fluctuations of systolic blood pressure (from 92.1 +/- 12.6 to 191 +/- 37.0 mm Hg) and diastolic one (from 57.3 +/- 11.4 to 118.9 +/- 13.8 mm Hg) were observed. Mean systolic blood pressure (125.6 +/- 10.6 mm Hg) was significantly lower than the mean value of last three ambulatory measurements (141.9 +/- 9.8; p less than 0.001). Also mean diastolic pressure was lower than that obtained in the out patient clinic (84.7 +/- 9.7 vs 91.9 +/- 3.2 mm Hg; p less than 0.001). Mean heart rate during the day was 86.2 +/- 10.7 and at night 69.7 +/- 10.5 beats per minute. Ventricular and/or supraventricular cardiac arrhythmias were observed in 14 (28%) of examined patients. Results of the study indicate, that 24-hour automatic blood pressure recording is the valuable method, affording possibilities for more precise estimation of blood pressure and its 24-hour fluctuations in patients with borderline hypertension. PMID:2639977

  9. Flexible and waterproof micro-sensors to uncover zebrafish circadian rhythms: The next generation of cardiac monitoring for drug screening.

    PubMed

    Zhang, Xiaoxiao; Beebe, Tyler; Jen, Nelson; Lee, Chia-An; Tai, Yuchong; Hsiai, Tzung K

    2015-09-15

    Flexible electronics are the next generation of sensors for mobile health and implantation. Zebrafish (Danio rerio) is an emergent strategy for pre-clinical drug development and toxicity testing. To address the confounding effects from sedation of fish and removal from the aquatic habitat for micro-electrocardiogram (µECG) measurements, we developed waterproof and wearable sensors to uncover the circadian variation in heart rate (HR) and heart rate variability (HRV) (Massin et al., 2000). The parylene-C based ECG sensor consisted of an ultra-soft silicone integrated jacket designed to wrap around the fish during swimming. The Young's modulus of this silicone jacket matched with the fish surface, and an extended parylene cable connected the underwater chest electrodes with the out-of water electronics. In addition, embedded micro-glass spheres in the silicone effectively reduced the effective density of the jacket to ~1 g cm(-3). These innovations enabled physiological ECG telemetry in the fish's natural habitat without the need for sedation. Furthermore, a set of non-linear signal processing techniques filtered out the breathing and electromagnetic artifacts from the recorded signals. We observed a reduction in mean HR and an increase in HRV over 24h at 10 dpa, accompanied by QT prolongation as well as diurnal variations, followed by normalization in mean HR and QT intervals at 26 days post ventricular amputation (dpa). We revealed Amiodarone-mediated QTc prolongation, HR reduction and HRV increase otherwise masked by sedation. The novel features of the flexible silicon jacket for µECG telemetry unraveled the biological clock and normalization of QT intervals at 26 dpa, providing the first evidence of new physiological phenomena during cardiac injury and repair as well as cardiac drug-mediated aberrant rhythms. Thus, the light weight and waterproof design holds promise to advance the next generation of mobile health and drug discovery. PMID:25909335

  10. Physiologic abnormalities of cardiac function in progressive systemic sclerosis with diffuse scleroderma

    SciTech Connect

    Follansbee, W.P.; Curtiss, E.I.; Medsger, T.A. Jr.; Steen, V.D.; Uretsky, B.F.; Owens, G.R.; Rodnan, G.P.

    1984-01-19

    To investigate cardiopulmonary function in progressive systemic sclerosis with diffuse scleroderma, we studied 26 patients with maximal exercise and redistribution thallium scans, rest and exercise radionuclide ventriculography, pulmonary-function testing, and chest roentgenography. Although only 6 patients had clinical evidence of cardiac involvement, 20 had abnormal thallium scans, including 10 with reversible exercise-induced defects and 18 with fixed defects (8 had both). Seven of the 10 patients who had exercise-induced defects and underwent cardiac catheterization had normal coronary angiograms. Mean resting left ventricular ejection fraction and mean resting right ventricular ejection fraction were lower in patients with post-exercise left ventricular thallium defect scores above the median (59 +/- 13 per cent vs. 69 +/- 6 per cent, and 36 +/- 12 per cent vs. 47 +/- 7 per cent, respectively). The authors conclude that in progressive systemic sclerosis with diffuse scleroderma, abnormalities of myocardial perfusion are common and appear to be due to a disturbance of the myocardial microcirculation. Both right and left ventricular dysfunction appear to be related to this circulatory disturbance, suggesting ischemically mediated injury.

  11. Do thallium myocardial perfusion scan abnormalities predict survival in sarcoid patients without cardiac symptoms

    SciTech Connect

    Kinney, E.L.; Caldwell, J.W. )

    1990-07-01

    Whereas the total mortality rate for sarcoidosis is 0.2 per 100,000, the prognosis, when the heart is involved, is very much worse. The authors used the difference in mortality rate to infer whether thallium 201 myocardial perfusion scan abnormalities correspond to myocardial sarcoid by making the simplifying assumption that if they do, then patients with abnormal scans will be found to have a death rate similar to patients with sarcoid heart disease. The authors therefore analyzed complete survival data on 52 sarcoid patients without cardiac symptoms an average of eighty-nine months after they had been scanned as part of a protocol. By use of survival analysis (the Cox proportional hazards model), the only variable that was significantly associated with survival was age. The patients' scan pattern, treatment status, gender, and race were not significantly related to survival. The authors conclude that thallium myocardial perfusion scans cannot reliably be used to diagnose sarcoid heart disease in sarcoid patients without cardiac symptoms.

  12. Assessment of Cardiac Rate and Rhythm in Fetuses with Arrhythmia via Maternal Abdominal Fetal Electrocardiography

    PubMed Central

    Narayan, Hari K.; Vignola, Emilia F.; Fifer, William P.; Williams, Ismee A.

    2015-01-01

    Objective This study aims to report our experience using the Monica AN24 (Monica Healthcare Ltd., Nottingham, United Kingdom), a maternal transabdominal fetal electrocardiographic monitor, in a case series of fetuses with arrhythmias. Study Design We recorded fetal electrocardiograms (fECGs) on subjects with fetal arrhythmias diagnosed by fetal echocardiogram. Fetal heart rate and rhythm were determined via manual fECG analysis. Results Overall, 20 fECGs were recorded from a pool of 13 subjects. Fetal heart rate acquisition was determined to be high, medium, and poor quality in 10, 3, and 7 tracings, respectively. High-quality tracings were obtained in 9 of 11 subjects with gestational age < 26 or > 34 weeks. P waves were detectable in five tracings. Conclusion In subjects < 26 or > 34 weeks' gestational age, there was reasonable success in fetal heart rate acquisition. Further study is warranted to determine the potential role of this device in the monitoring of subjects with fetal arrhythmias. PMID:26495180

  13. Optical monitoring of cardiac and respiratory rhythms in the skin perfusion near the brain under controlled conditions

    NASA Astrophysics Data System (ADS)

    Mukunda Rao, M.; Blazek, Vladimir; Schmitt, Hans J.

    1998-04-01

    In this investigation an attempt is made to find the effects of controlled breathing on brain with the help of optical sensor mounted on the left and right temples of a subject. It has already been established that the brain activity can be monitored in terms of arterial blood volumetric changes to the left and right hemispheres of the brain recorded with the help of optical sensors. To investigate the influence of controlled breathing, an expert in controlled breathing is chosen as the subject. Pranayama is believed to be the controlled intake and outflow of breath in a firmly established posture. Some types of pranayama are believed to relieve mental stress. While the subject is practicing one such type of breath control, arterial blood volume changes in the brain are recorded using optical sensor mounted on the left and right temples of the subject. From these measurements at the beginning and end of the pranayama exercise, it could be noticed that the subject could induce changes in the cardiac and respiratory rhythms by controlled breathing. Rhythmic phenomena in the skin perfusion in the vicinity of the brian are also studied when the subject is holding his breath. The arterial blood volume changes to the left and right hemispheres of the brian, as monitored by the optical sensors during this period, exhibit asymmetric reaction when the subject is holding his breath. An attempt is made to understand whether these changes induced by stoppage of breathing are 'chaotic' or 'adaptive' in nature.

  14. Optical monitoring of cardiac and respiratory rhythms in the skin perfusion near the brain under controlled conditions

    NASA Astrophysics Data System (ADS)

    Mukunda Rao, M.; Blazek, Vladimir; Schmitt, Hans J.

    1998-06-01

    In this investigation an attempt is made to find the effects of controlled breathing on brain with the help of optical sensors mounted on the left and right temples of a subject. It has already been established that the brain activity can be monitored in terms of arterial blood volumetric changes to the left and right hemispheres of the brain recorded with the help of optical sensors. To investigate the influence of controlled breathing, an expert in controlled breathing (pranayama) is chosen as the subject. Pranayama is believed to be the controlled intake and outflow of breath in a firmly established posture. Some types of pranayama are believed to relive mental stress. While the subject is practicing one such type of breath control, arterial blood volume changes in the brain are recorded using optical sensors mounted on the left and right temples of the subject. From these measurements at the beginning and end of the pranayama exercise, it could be noticed that the subject could induce changes in the cardiac and respiratory rhythms by controlled breathing. Rhythmic phenomena in the skin perfusion in the vicinity of the brian are also studied when the subject is holding his breath. The arterial blood volume changes to the left and right hemispheres of the brain, as monitored by the optical sensors during this period, exhibit asymmetric reaction when the subject is holding his breath. An attempt is made to understand whether these changes induced by stoppage of breathing are 'chaotic' or 'adaptive' in nature.

  15. Abnormal left ventricular torsion and cardiac autonomic dysfunction in subjects with type 1 diabetes mellitus

    PubMed Central

    Piya, Milan K.; Shivu, Ganesh Nallur; Tahrani, Abd; Dubb, Kiran; Abozguia, Khalid; Phan, T.T.; Narendran, Parth; Pop-Busui, Rodica; Frenneaux, Michael; Stevens, Martin J.

    2011-01-01

    Left ventricular torsion is increased and cardiac energetics are reduced in uncomplicated type 1 diabetes mellitus (T1DM). Our aim was to determine the relationships of these abnormalities to cardiovascular autonomic neuropathy (CAN) in subjects with T1DM. A cross-sectional study was conducted in 20 subjects with T1DM free of known coronary heart disease attending an outpatient clinic. Cardiovascular autonomic neuropathy was assessed using heart rate variability studies and the continuous wavelet transform method. Left ventricular function was determined by speckle tracking echocardiography. Magnetic resonance spectroscopy and stress magnetic resonance imaging were used to measure cardiac energetics and myocardial perfusion reserve index, respectively. Twenty subjects (age, 35 ± 8 years; diabetes duration, 16 ± 9 years; hemoglobin A1c, 8.0% ± 1.1%) were recruited. Forty percent of the subjects exhibited definite or borderline CAN. Log peak radial strain was significantly increased in subjects with CAN compared with those without (1.56 ± 0.06 vs 1.43 ± 0.14, respectively; P = .011). Data were adjusted for log duration of diabetes, and log left ventricular torsion correlated (r = 0.593, P = .01) with log low-frequency to high-frequency ratio during the Valsalva maneuver. Log isovolumic relaxation time correlated significantly with log Valsalva ratio and log proportion of differences in consecutive RR intervals of normal beats greater than 50 milliseconds during deep breathing. However, CAN did not correlate with cardiac energetics or myocardial perfusion reserve index. Spectral analysis of low-frequency to high-frequency ratio power during the Valsalva maneuver is associated with altered left ventricular torsion in subjects with T1DM. Parasympathetic dysfunction is closely associated with diastolic deficits. Cardiovascular autonomic neuropathy is not however the principal cause of impaired cardiac energetics. The role of CAN in the development of cardiomyopathy

  16. Cardiovascular rhythms and cardiac baroreflex sensitivity in AT(1A) receptor gain-of-function mutant mice.

    PubMed

    Palma-Rigo, Kesia; Baudrie, Véronique; Laude, Dominique; Petrel, Christophe; Clauser, Eric; Elghozi, Jean-Luc

    2010-01-01

    A mutant mouse expressing a gain-of-function of the AT(1A) angiotensin II receptor was engineered to study the consequences of a constitutive activation of this receptor on blood pressure (BP). Cardiovascular rhythms and spontaneous cardiac baroreflex sensitivity (BRS) were evaluated using telemetric BP recordings of five transgenic (AT(1A)MUT) and five wild (AT(1A)WT) mice. The circadian rhythms were described with the Chronos-Fit program. The gain of the transfer function between systolic BP (SBP) and pulse intervals used to estimate the spontaneous BRS (ms/mmHg) was calculated in the low frequency (0.15-0.60 Hz) band. Transgenic AT(1A)MUT exhibited higher BP and heart rate (HR) levels compared to controls (SBP AT(1A)MUT 134.6 +/- 5.9 mmHg vs. AT(1A)WT 110.5 +/- 5.9; p < 0.05; HR AT(1A)MUT 531.0 +/- 14.9 vs. AT(1A)WT 454.8 +/- 5.4 beats/min; p = 0.001). Spontaneous BRS was diminished in transgenic mice (AT(1A)MUT 1.23 +/- 0.17 ms/mmHg vs. AT(1A)WT 1.91 +/- 0.18 ms/mmHg; p < 0.05). Motor activity did not differ between groups. These variables exhibited circadian changes, and the differences between the strains were maintained throughout the cycle. The highest values for BP, HR, and locomotor activity were observed at night. Spontaneous BRS varied in the opposite direction, with the lowest gain estimated when BP and HR were elevated (i.e., at night, when the animals were active). It is likely the BP elevation of the mutant mice results from the amplification of the effects of AngII at different sites. Future studies are necessary to explore whether AT(1A) receptor activation at the central nervous system level effectively contributed to the observed differences. PMID:20205562

  17. Abnormal sodium current properties contribute to cardiac electrical and contractile dysfunction in a mouse model of myotonic dystrophy type 1.

    PubMed

    Algalarrondo, Vincent; Wahbi, Karim; Sebag, Frédéric; Gourdon, Geneviève; Beldjord, Chérif; Azibi, Kamel; Balse, Elise; Coulombe, Alain; Fischmeister, Rodolphe; Eymard, Bruno; Duboc, Denis; Hatem, Stéphane N

    2015-04-01

    Myotonic dystrophy type 1 (DM1) is the most common neuromuscular disorder and is associated with cardiac conduction defects. However, the mechanisms of cardiac arrhythmias in DM1 are unknown. We tested the hypothesis that abnormalities in the cardiac sodium current (INa) are involved, and used a transgenic mouse model reproducing the expression of triplet expansion observed in DM1 (DMSXL mouse). The injection of the class-I antiarrhythmic agent flecainide induced prominent conduction abnormalities and significantly lowered the radial tissular velocities and strain rate in DMSXL mice compared to WT. These abnormalities were more pronounced in 8-month-old mice than in 3-month-old mice. Ventricular action potentials recorded by standard glass microelectrode technique exhibited a lower maximum upstroke velocity [dV/dt](max) in DMSXL. This decreased [dV/dt](max) was associated with a 1.7 fold faster inactivation of INa in DMSXL myocytes measured by the whole-cell patch-clamp technique. Finally in the DMSXL mouse, no mutation in the Scn5a gene was detected and neither cardiac fibrosis nor abnormalities of expression of the sodium channel protein were observed. Therefore, alterations in the sodium current markedly contributed to electrical conduction block in DM1. This result should guide pharmaceutical and clinical research toward better therapy for the cardiac arrhythmias associated with DM1. PMID:25613807

  18. Diastolic abnormalities in systemic sclerosis: evidence for associated defective cardiac functional reserve.

    PubMed Central

    Valentini, G; Vitale, D F; Giunta, A; Maione, S; Gerundo, G; Arnese, M; Tirri, E; Pelaggi, N; Giacummo, A; Tirri, G; Condorelli, M

    1996-01-01

    OBJECTIVE: To investigate the pattern of diastolic abnormalities in patients with systemic sclerosis (SSc) and the relationship between impaired ventricular filling and systolic function. METHODS: Twenty four patients with SSc underwent M-mode and two dimensional echocardiography using echo-Doppler and gated blood pool cardiac angiography, both at rest and after exercise. RESULTS: An impaired diastolic relaxation of the left ventricle was detected in 10 of the 24 patients with SSc. Left ventricular ejection fraction at rest in these 10 patients with impaired ventricular filling did not differ from that in the remaining 14 patients, but eight of the 10 failed to increase their ejection fraction during exercise, compared with two of the 14 with normal ventricular filling (p = 0.003). CONCLUSION: Impaired relaxation of the left ventricle is a recently described feature of scleroderma heart disease. Diastolic dysfunction in SSc could depend on myocardial fibrosis or myocardial ischaemia, or both. It was found to be associated with a defective cardiac functional reserve. However, its prognostic significance remains to be clarified. PMID:8774164

  19. 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

  20. Disruption of Ah Receptor Signaling during Mouse Development Leads to Abnormal Cardiac Structure and Function in the Adult.

    PubMed

    Carreira, Vinicius S; Fan, Yunxia; Kurita, Hisaka; Wang, Qin; Ko, Chia-I; Naticchioni, Mindi; Jiang, Min; Koch, Sheryl; Zhang, Xiang; Biesiada, Jacek; Medvedovic, Mario; Xia, Ying; Rubinstein, Jack; Puga, Alvaro

    2015-01-01

    The Developmental Origins of Health and Disease (DOHaD) Theory proposes that the environment encountered during fetal life and infancy permanently shapes tissue physiology and homeostasis such that damage resulting from maternal stress, poor nutrition or exposure to environmental agents may be at the heart of adult onset disease. Interference with endogenous developmental functions of the aryl hydrocarbon receptor (AHR), either by gene ablation or by exposure in utero to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent AHR ligand, causes structural, molecular and functional cardiac abnormalities and altered heart physiology in mouse embryos. To test if embryonic effects progress into an adult phenotype, we investigated whether Ahr ablation or TCDD exposure in utero resulted in cardiac abnormalities in adult mice long after removal of the agent. Ten-months old adult Ahr-/- and in utero TCDD-exposed Ahr+/+ mice showed sexually dimorphic abnormal cardiovascular phenotypes characterized by echocardiographic findings of hypertrophy, ventricular dilation and increased heart weight, resting heart rate and systolic and mean blood pressure, and decreased exercise tolerance. Underlying these effects, genes in signaling networks related to cardiac hypertrophy and mitochondrial function were differentially expressed. Cardiac dysfunction in mouse embryos resulting from AHR signaling disruption seems to progress into abnormal cardiac structure and function that predispose adults to cardiac disease, but while embryonic dysfunction is equally robust in males and females, the adult abnormalities are more prevalent in females, with the highest severity in Ahr-/- females. The findings reported here underscore the conclusion that AHR signaling in the developing heart is one potential target of environmental factors associated with cardiovascular disease. PMID:26555816

  1. Disruption of Ah Receptor Signaling during Mouse Development Leads to Abnormal Cardiac Structure and Function in the Adult

    PubMed Central

    Carreira, Vinicius S.; Fan, Yunxia; Kurita, Hisaka; Wang, Qin; Ko, Chia-I; Naticchioni, Mindi; Jiang, Min; Koch, Sheryl; Zhang, Xiang; Biesiada, Jacek; Medvedovic, Mario; Xia, Ying; Rubinstein, Jack; Puga, Alvaro

    2015-01-01

    The Developmental Origins of Health and Disease (DOHaD) Theory proposes that the environment encountered during fetal life and infancy permanently shapes tissue physiology and homeostasis such that damage resulting from maternal stress, poor nutrition or exposure to environmental agents may be at the heart of adult onset disease. Interference with endogenous developmental functions of the aryl hydrocarbon receptor (AHR), either by gene ablation or by exposure in utero to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent AHR ligand, causes structural, molecular and functional cardiac abnormalities and altered heart physiology in mouse embryos. To test if embryonic effects progress into an adult phenotype, we investigated whether Ahr ablation or TCDD exposure in utero resulted in cardiac abnormalities in adult mice long after removal of the agent. Ten-months old adult Ahr-/- and in utero TCDD-exposed Ahr+/+ mice showed sexually dimorphic abnormal cardiovascular phenotypes characterized by echocardiographic findings of hypertrophy, ventricular dilation and increased heart weight, resting heart rate and systolic and mean blood pressure, and decreased exercise tolerance. Underlying these effects, genes in signaling networks related to cardiac hypertrophy and mitochondrial function were differentially expressed. Cardiac dysfunction in mouse embryos resulting from AHR signaling disruption seems to progress into abnormal cardiac structure and function that predispose adults to cardiac disease, but while embryonic dysfunction is equally robust in males and females, the adult abnormalities are more prevalent in females, with the highest severity in Ahr-/- females. The findings reported here underscore the conclusion that AHR signaling in the developing heart is one potential target of environmental factors associated with cardiovascular disease. PMID:26555816

  2. Identifying regional cardiac abnormalities from myocardial strains using nontracking-based strain estimation and spatio-temporal tensor analysis.

    PubMed

    Qian, Zhen; Liu, Qingshan; Metaxas, Dimitris N; Axel, Leon

    2011-12-01

    Myocardial strain is a critical indicator of many cardiac diseases and dysfunctions. The goal of this paper is to extract and use the myocardial strain pattern from tagged magnetic resonance imaging (MRI) to identify and localize regional abnormal cardiac function in human subjects. In order to extract the myocardial strains from the tagged images, we developed a novel nontracking-based strain estimation method for tagged MRI. This method is based on the direct extraction of tag deformation, and therefore avoids some limitations of conventional displacement or tracking-based strain estimators. Based on the extracted spatio-temporal strain patterns, we have also developed a novel tensor-based classification framework that better conserves the spatio-temporal structure of the myocardial strain pattern than conventional vector-based classification algorithms. In addition, the tensor-based projection function keeps more of the information of the original feature space, so that abnormal tensors in the subspace can be back-projected to reveal the regional cardiac abnormality in a more physically meaningful way. We have tested our novel methods on 41 human image sequences, and achieved a classification rate of 87.80%. The regional abnormalities recovered from our algorithm agree well with the patient's pathology and clinical image interpretation, and provide a promising avenue for regional cardiac function analysis. PMID:21606022

  3. Is it possible to identify infrahissian cardiac conduction abnormalities in myotonic dystrophy by non-invasive methods?

    PubMed Central

    Babuty, D; Fauchier, L; Tena-Carbi, D; Poret, P; Leche, J; Raynaud, M; Fauchier, J; Cosnay, P

    1999-01-01

    OBJECTIVE—To identify intracardiac conduction abnormalities in patients with myotonic dystrophy from their clinical, ECG, and genetic features.
METHODS—39 consecutive patients (mean (SD) age 42.9 (12.1) years; 16 female, 23 male) underwent clinical examination, genetic studies, resting and 24 hour ambulatory ECG, signal averaged ECG, and electrophysiological studies.
RESULTS—23 patients suffered from cardiac symptoms, 23 had one or more cardiac conduction abnormality on resting ECG, one had sinus deficiency, and 21 (53.8%) had prolonged HV intervals. No correlation was found between the severity of the neurological symptoms, onset of disease, cardiac conduction abnormalities on ECG, and the intracardiac conduction abnormalities on electrophysiological study. The size of the DNA mutation was longer in the abnormal HV interval group than in the normal HV interval group (3.5 (1.8) v 2.2 (1.0) kb, p < 0.02). Signal averaged ECG parameters (total QRS duration (QRSD) and duration of low amplitude signals ⩽ 40 µV (LAS 40)) were greater in patients with an abnormal HV interval than in those with a normal HV interval (123.4 (24.6) v 102.8 (12.3) ms and 47.5 (12.8) v 35.3 (8.8) ms, respectively; p < 0.005). Only the association of QRSD ⩾ 100 ms with LAS 40 ⩾ 36 ms identified patients with an abnormal HV interval with good sensitivity (80%) and specificity (83.3%).
CONCLUSIONS—Infrahissian conduction abnormalities are common in myotonic dystrophy and can be identified using signal averaged electrocardiography.


Keywords: myotonic dystrophy; atrioventricular block; genetic factors; signal averaged ECG PMID:10525524

  4. The Effect of Sorafenib, Tadalafil and Macitentan Treatments on Thyroxin-Induced Hemodynamic Changes and Cardiac Abnormalities

    PubMed Central

    Saad, Nancy S.; Floyd, Kyle; Ahmed, Amany A. E.; Mohler, Peter J.

    2016-01-01

    Multikinase inhibitors (e.g. Sorafenib), phosphodiesterase-5 inhibitors (e.g. Tadalafil), and endothelin-1 receptor blockers (e.g. Macitentan) exert influential protection in a variety of animal models of cardiomyopathy; however, their effects on thyroxin-induced cardiomyopathy have never been investigated. The goal of the present study was to assess the functional impact of these drugs on thyroxin-induced hemodynamic changes, cardiac hypertrophy and associated altered responses of the contractile myocardium both in-vivo at the whole heart level and ex-vivo at the cardiac tissue level. Control and thyroxin (500 μg/kg/day)-treated mice with or without 2-week treatments of sorafenib (10 mg/kg/day; I.P), tadalafil (1 mg/kg/day; I.P or 4 mg/kg/day; oral), macitentan (30 and 100 mg/kg/day; oral), and their vehicles were studied. Blood pressure, echocardiography and electrocardiogram were non-invasively evaluated, followed by ex-vivo assessments of isolated multicellular cardiac preparations. Thyroxin increased blood pressure, resulted in cardiac hypertrophy and left ventricular dysfunction in-vivo. Also, it caused contractile abnormalities in right ventricular papillary muscles ex-vivo. None of the drug treatments were able to significantly attenuate theses hemodynamic changes or cardiac abnormalities in thyroxin-treated mice. We show here for the first time that multikinase (raf1/b, VEGFR, PDGFR), phosphodiesterase-5, and endothelin-1 pathways have no major role in thyroxin-induced hemodynamic changes and cardiac abnormalities. In particular, our data show that the involvement of endothelin-1 pathway in thyroxine-induced cardiac hypertrophy/dysfunction seems to be model-dependent and should be carefully interpreted. PMID:27082116

  5. The Effect of Sorafenib, Tadalafil and Macitentan Treatments on Thyroxin-Induced Hemodynamic Changes and Cardiac Abnormalities.

    PubMed

    Saad, Nancy S; Floyd, Kyle; Ahmed, Amany A E; Mohler, Peter J; Janssen, Paul M L; Elnakish, Mohammad T

    2016-01-01

    Multikinase inhibitors (e.g. Sorafenib), phosphodiesterase-5 inhibitors (e.g. Tadalafil), and endothelin-1 receptor blockers (e.g. Macitentan) exert influential protection in a variety of animal models of cardiomyopathy; however, their effects on thyroxin-induced cardiomyopathy have never been investigated. The goal of the present study was to assess the functional impact of these drugs on thyroxin-induced hemodynamic changes, cardiac hypertrophy and associated altered responses of the contractile myocardium both in-vivo at the whole heart level and ex-vivo at the cardiac tissue level. Control and thyroxin (500 μg/kg/day)-treated mice with or without 2-week treatments of sorafenib (10 mg/kg/day; I.P), tadalafil (1 mg/kg/day; I.P or 4 mg/kg/day; oral), macitentan (30 and 100 mg/kg/day; oral), and their vehicles were studied. Blood pressure, echocardiography and electrocardiogram were non-invasively evaluated, followed by ex-vivo assessments of isolated multicellular cardiac preparations. Thyroxin increased blood pressure, resulted in cardiac hypertrophy and left ventricular dysfunction in-vivo. Also, it caused contractile abnormalities in right ventricular papillary muscles ex-vivo. None of the drug treatments were able to significantly attenuate theses hemodynamic changes or cardiac abnormalities in thyroxin-treated mice. We show here for the first time that multikinase (raf1/b, VEGFR, PDGFR), phosphodiesterase-5, and endothelin-1 pathways have no major role in thyroxin-induced hemodynamic changes and cardiac abnormalities. In particular, our data show that the involvement of endothelin-1 pathway in thyroxine-induced cardiac hypertrophy/dysfunction seems to be model-dependent and should be carefully interpreted. PMID:27082116

  6. Detection of abnormal cardiac activity using principal component analysis--a theoretical study.

    PubMed

    Greisas, Ariel; Zafrir, Zohar; Zlochiver, Sharon

    2015-01-01

    Electrogram-guided ablation has been recently developed for allowing better detection and localization of abnormal atrial activity that may be the source of arrhythmogeneity. Nevertheless, no clear indication for the benefit of using electrograms guided ablation over empirical ablation was established thus far, and there is a clear need of improving the localization of cardiac arrhythmogenic targets for ablation. In this paper, we propose a new approach for detection and localization of irregular cardiac activity during ablation procedures that is based on dimension reduction algorithms and principal component analysis (PCA). Using an 8×8 electrode array, our method produces manifolds that allow easy visualization and detection of possible arrhythmogenic ablation targets characterized by irregular conduction. We employ mathematical modeling and computer simulations to demonstrate the feasibility of the new approach for two well established arrhythmogenic sources for irregular conduction--spiral waves and patchy fibrosis. Our results show that the PCA method can differentiate between focal ectopic activity and spiral wave activity, as these two types of activity produce substantially different manifold shapes. Moreover, the technique allows the detection of spiral wave cores and their general meandering and drifting pattern. Fibrotic patches larger than 2 mm(2) could also be visualized using the PCA method, both for quiescent atrial tissue and for tissue exhibiting spiral wave activity. We envision that this method, contingent to further numerical and experimental validation studies in more complex, realistic geometrical configurations and with clinical data, can improve existing atrial ablation mapping capabilities, thus increasing success rates and optimizing arrhythmia management. PMID:25073163

  7. The Cardiac Electrophysiologic Substrate Underlying the ECG Phenotype and Electrogram Abnormalities in Brugada Syndrome Patients

    PubMed Central

    Zhang, Junjie; Sacher, Frédéric; Hoffmayer, Kurt; O’Hara, Thomas; Strom, Maria; Cuculich, Phillip; Silva, Jennifer; Cooper, Daniel; Faddis, Mitchell; Hocini, Mélèze; Haïssaguerre, Michel; Scheinman, Melvin; Rudy, Yoram

    2015-01-01

    Background Brugada syndrome (BrS) is a highly arrhythmogenic cardiac disorder, associated with an increased incidence of sudden death. Its arrhythmogenic substrate in the intact human heart remains ill-defined. Methods and Results Using noninvasive ECG imaging (ECGI), we studied 25 BrS patients to characterize the electrophysiologic substrate, and 6 patients with right bundle branch block (RBBB) for comparison. Seven normal subjects provided control data. Abnormal substrate was observed exclusively in the right ventricular outflow tract (RVOT) with the following properties (compared to normal controls; p<0.005): (1)ST-segment elevation (STE) and inverted T-wave of unipolar electrograms (EGMs) (2.21±0.67 vs. 0 mV); (2)delayed RVOT activation (82±18 vs. 37±11 ms); (3)low amplitude (0.47±0.16 vs. 3.74±1.60 mV) and fractionated EGMs, suggesting slow discontinuous conduction; (4)prolonged recovery time (RT; 381±30 vs. 311±34 ms) and activation-recovery intervals (ARIs; 318±32 vs. 241±27 ms), indicating delayed repolarization; (5)steep repolarization gradients (ΔRT/Δx= 96±28 vs. 7±6 ms/cm, ΔARI/Δx= 105±24 vs. 7±5 ms/cm) at RVOT borders. With increased heart rate in 6 BrS patients, reduced STE and increased fractionation were observed. Unlike BrS, RBBB had delayed activation in the entire RV, without STE, fractionation, or repolarization abnormalities on EGMs. Conclusions The results indicate that both, slow discontinuous conduction and steep dispersion of repolarization are present in the RVOT of BrS patients. ECGI could differentiate between BrS and RBBB. PMID:25810336

  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. 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

  10. Brugada syndrome and right ventricle morphofunctional abnormalities on echocardiography in young male with family anamnesis of sudden cardiac death.

    PubMed

    Steiner, Robert; Makarovic, Sandra; Makarovic, Zorin; Bilic-Curcic, Ines

    2014-03-01

    First presented by Brugada and Brugada in 1992, Brugada Syndrome (BrS) is a primary electrical disease of the heart that causes sudden cardiac death or life-threatening ventricular arrhythmias. This disease is hereditary autosomic dominant transmitted and genetically determined. The syndrome has been linked to mutations in SCN5A, the gene encoding for the a-subunit of the sodium channel. Electrocardiogram (ECG) abnormalities indicating Brugada syndrome, include repolarization and depolarization abnormalities in the absence of identifiable structural cardiac abnormalities or other conditions or agents known to lead to ST-segment elevation in the right precordial leads (V1-V3). Intravenous administration of sodium channel blocking drugs may modify the ECG pattern. Ajmaline, flecainide, procainamide and propafenone exaggerate the ST-segment elevation or unmask it when it is initially absent. An implantable cardioverter-defibrillator (ICD) is the only proven effective device treatment for the disease. Although BrS is primary electrical disease, some authors have suggested the presence of morphological and functional abnormalities mainly located in the right ventricle (RV), notably in the outflow tract (RVOT). In this short report we will present a young male, with predisposition and positive family history of sudden cardiac death, with complete diagnostic procedure including propafenon testing unmasking Brugada syndrome. An echosonography revealed dilated apical right ventricle, suggesting BrS is not only electrical disorder, but may include morphofunctional abnormalities, described in previous reports. In addition, we reviewed the possible connection between Brugada syndrome and morphological abnormalities in RV. PMID:24851643

  11. Association Between Tangential Beam Treatment Parameters and Cardiac Abnormalities After Definitive Radiation Treatment for Left-Sided Breast Cancer

    SciTech Connect

    Correa, Candace R.; Das, Indra J. Litt, Harold I.; Ferrari, Victor; Hwang, W.-T.; Solin, Lawrence J.; Harris, Eleanor E.

    2008-10-01

    Purpose: To examine the association between radiation treatment (RT) parameters, cardiac diagnostic test abnormalities, and clinical cardiovascular diagnoses among patients with left-sided breast cancer after breast conservation treatment with tangential beam RT. Methods and Materials: The medical records of 416 patients treated between 1977 and 1995 with RT for primary left-sided breast cancer were reviewed for myocardial perfusion imaging and echocardiograms. Sixty-two patients (62/416, 15%) underwent these cardiac diagnostic tests for cardiovascular symptoms and were selected for further study. Central lung distance and maximum heart width and length in the treatment field were determined for each patient. Medical records were reviewed for cardiovascular diagnoses and evaluation of cardiac risk factors. Results: At a median of 12 years post-RT the incidence of cardiac diagnostic test abnormalities among symptomatic left-sided irradiated women was significantly higher than the predicted incidence of cardiovascular disease in the patient population, 6/62 (9%) predicted vs. 24/62 (39%) observed, p 0.001. As compared with patients with normal tests, patients with cardiac diagnostic test abnormalities had a larger median central lung distance (2.6 cm vs. 2.2 cm, p = 0.01). Similarly, patients with vs. without congestive heart failure had a larger median central lung distance (2.8 cm vs. 2.3 cm, p = 0.008). Conclusions: Contemporary RT for early breast cancer may be associated with a small, but potentially avoidable, risk of cardiovascular morbidity that is associated with treatment technique.

  12. Modulation of Cardiac Potassium Current by Neural Tone and Ischemia.

    PubMed

    Tomson, Todd T; Arora, Rishi

    2016-06-01

    The cardiac action potential is generated by intricate flows of ions across myocyte cell membranes in a coordinated fashion to control myocardial contraction and the heart rhythm. Modulation of the flow of these ions in response to a variety of stimuli results in changes to the action potential. Abnormal or altered ion currents can result in cardiac arrhythmias. Abnormalities of autonomic regulation of potassium current play a role in the genesis of cardiac arrhythmias, and alterations in acetylcholine-activated potassium channels may play a key role in atrial fibrillation. Ischemia is another important modulator of cardiac cellular electrophysiology. PMID:27261826

  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. Incidence of cardiac abnormalities in children with human immunodeficiency virus infection: The Prospective P2C2 HIV Study

    PubMed Central

    Starc, Thomas J.; Lipshultz, Steven E.; Easley, Kirk A.; Kaplan, Samuel; Bricker, J. Timothy; Colan, Steven D.; Lai, Wyman W.; Gersony, Welton M.; Sopko, George; Moodie, Douglas S.; Schluchter, Mark D.

    2015-01-01

    Objective To describe the 5-year cumulative incidence of cardiac dysfunction in human immunodeficiency virus (HIV)-infected children. Study design We used a prospective cohort design, enrolling children at 10 hospitals. Group I included 205 vertically HIV-infected children enrolled at a median age of 1.9 years. Group II consisted of 600 HIV-exposed children enrolled prenatally or as neonates, of whom 93 were ultimately HIV-infected. The main outcome measures were echocardiographic indexes of left ventricular dysfunction. Results In group I, the 5-year cumulative incidence of left ventricular fractional shortening ≤25% was 28.0%. The 5-year incidence of left ventricular end-diastolic dilatation was 21.7%, and heart failure and/or the use of cardiac medications 28.8%. The mortality rate 1 year after the diagnosis of heart failure was 52.5% [95% CI, 30.5-74.5]. Within group II, the 5-year cumulative incidence of decreased fractional shortening was 10.7% in the HIV-infected compared with 3.1% in the HIV-uninfected children (P = .01). Left ventricular dilation, heart failure, and/or the use of cardiac medications were more common in infected compared with uninfected children. Conclusions During 5 years of follow-up, cardiac dysfunction occurred in 18% to 39% of HIV-infected children and was associated with an increased risk of death. We recommend that HIV-infected children undergo routine echocardiographic surveillance for cardiac abnormalities. PMID:12219051

  15. A transgenic zebrafish model of a human cardiac sodium channel mutation exhibits bradycardia, conduction-system abnormalities and early death.

    PubMed

    Huttner, Inken G; Trivedi, Gunjan; Jacoby, Arie; Mann, Stefan A; Vandenberg, Jamie I; Fatkin, Diane

    2013-08-01

    The recent exponential increase in human genetic studies due to the advances of next generation sequencing has generated unprecedented numbers of new gene variants. Determining which of these are causative of human disease is a major challenge. In-vitro studies and murine models have been used to study inherited cardiac arrhythmias but have several limitations. Zebrafish models provide an attractive alternative for modeling human heart disease due to similarities in cardiac electrophysiology and contraction, together with ease of genetic manipulation, external development and optical transparency. Although zebrafish cardiac mutants and morphants have been widely used to study loss and knockdown of zebrafish gene function, the phenotypic effects of human dominant-negative gene mutations expressed in transgenic zebrafish have not been evaluated. The aim of this study was to generate and characterize a transgenic zebrafish arrhythmia model harboring the pathogenic human cardiac sodium channel mutation SCN5A-D1275N, that has been robustly associated with a range of cardiac phenotypes, including conduction disease, sinus node dysfunction, atrial and ventricular arrhythmias, and dilated cardiomyopathy in humans and in mice. Stable transgenic fish with cardiac expression of human SCN5A were generated using Tol2-mediated transgenesis and cardiac phenotypes were analyzed using video microscopy and ECG. Here we show that transgenic zebrafish expressing the SCN5A-D1275N mutation, but not wild-type SCN5A, exhibit bradycardia, conduction-system abnormalities and premature death. We furthermore show that SCN5A-WT, and to a lesser degree SCN5A-D1275N, are able to compensate the loss of endogenous zebrafish cardiac sodium channels, indicating that the basic pathways, through which SCN5A acts, are conserved in teleosts. This proof-of-principle study suggests that zebrafish may be highly useful in vivo models to differentiate functional from benign human genetic variants in cardiac

  16. Finding the rhythm of sudden cardiac death: new opportunities using induced pluripotent stem cell-derived cardiomyocytes.

    PubMed

    Sallam, Karim; Li, Yingxin; Sager, Philip T; Houser, Steven R; Wu, Joseph C

    2015-06-01

    Sudden cardiac death is a common cause of death in patients with structural heart disease, genetic mutations, or acquired disorders affecting cardiac ion channels. A wide range of platforms exist to model and study disorders associated with sudden cardiac death. Human clinical studies are cumbersome and are thwarted by the extent of investigation that can be performed on human subjects. Animal models are limited by their degree of homology to human cardiac electrophysiology, including ion channel expression. Most commonly used cellular models are cellular transfection models, which are able to mimic the expression of a single-ion channel offering incomplete insight into changes of the action potential profile. Induced pluripotent stem cell-derived cardiomyocytes resemble, but are not identical, adult human cardiomyocytes and provide a new platform for studying arrhythmic disorders leading to sudden cardiac death. A variety of platforms exist to phenotype cellular models, including conventional and automated patch clamp, multielectrode array, and computational modeling. Induced pluripotent stem cell-derived cardiomyocytes have been used to study long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, hypertrophic cardiomyopathy, and other hereditary cardiac disorders. Although induced pluripotent stem cell-derived cardiomyocytes are distinct from adult cardiomyocytes, they provide a robust platform to advance the science and clinical care of sudden cardiac death. PMID:26044252

  17. Effects of carvedilol on cardiac autonomic nerve activities during sinus rhythm and atrial fibrillation in ambulatory dogs

    PubMed Central

    Choi, Eue-Keun; Shen, Mark J.; Lin, Shien-Fong; Chen, Peng-Sheng; Oh, Seil

    2014-01-01

    Aims We hypothesized that carvedilol can effectively suppress autonomic nerve activity (ANA) in ambulatory dogs during sinus rhythm and atrial fibrillation (AF), and that carvedilol withdrawal can lead to rebound elevation of ANA. Carvedilol is known to block pre-junctional β2-adrenoceptor responsible for norepinephrine release. Methods and results We implanted radiotransmitters to record stellate ganglion nerve activity (SGNA), vagal nerve activity (VNA), and superior left ganglionated plexi nerve activity (SLGPNA) in 12 ambulatory dogs. Carvedilol (12.5 mg orally twice a day) was given for 7 days during sinus rhythm (n = 8). Four of the eight dogs and an additional four dogs were paced into persistent AF. Carvedilol reduced heart rate [from 103 b.p.m. (95% confidence interval (CI), 100–105) to 100 b.p.m. (95% CI, 98–102), P = 0.044], suppressed integrated nerve activities (Int-NAs, SGNA by 17%, VNA by 19%, and SLGPNA by 12%; all P < 0.05 vs. the baseline), and significantly reduced the incidence (from 8 ± 6 to 3 ± 3 episodes/day, P < 0.05) and total duration (from 68 ± 64 to 16 ± 21 s/day, P < 0.05) of paroxysmal atrial tachycardia (PAT). Following the development of persistent AF, carvedilol loading was associated with AF termination in three dogs. In the remaining five dogs, Int-NAs were not significantly suppressed by carvedilol, but SGNA significantly increased by 16% after carvedilol withdrawal (P < 0.001). Conclusion Carvedilol suppresses ANA and PAT in ambulatory dogs during sinus rhythm. PMID:24469435

  18. Clinical investigation: thyroid function test abnormalities in cardiac arrest associated with acute coronary syndrome

    PubMed Central

    Iltumur, Kenan; Olmez, Gonul; Arıturk, Zuhal; Taskesen, Tuncay; Toprak, Nizamettin

    2005-01-01

    Introduction It is known that thyroid homeostasis is altered during the acute phase of cardiac arrest. However, it is not clear under what conditions, how and for how long these alterations occur. In the present study we examined thyroid function tests (TFTs) in the acute phase of cardiac arrest caused by acute coronary syndrome (ACS) and at the end of the first 2 months after the event. Method Fifty patients with cardiac arrest induced by ACS and 31 patients with acute myocardial infarction (AMI) who did not require cardioversion or cardiopulmonary resuscitation were enrolled in the study, as were 40 healthy volunteers. The patients were divided into three groups based on duration of cardiac arrest (<5 min, 5–10 min and >10 min). Blood samples were collected for thyroid-stimulating hormone (TSH), tri-iodothyronine (T3), free T3, thyroxine (T4), free T4, troponin-I and creatine kinase-MB measurements. The blood samples for TFTs were taken at 72 hours and at 2 months after the acute event in the cardiac arrest and AMI groups, but only once in the control group. Results The T3 and free T3 levels at 72 hours in the cardiac arrest group were significantly lower than in both the AMI and control groups (P < 0.0001). On the other hand, there were no significant differences between T4, free T4 and TSH levels between the three groups (P > 0.05). At the 2-month evaluation, a dramatic improvement was observed in T3 and free T3 levels in the cardiac arrest group (P < 0.0001). In those patients whose cardiac arrest duration was in excess of 10 min, levels of T3, free T3, T4 and TSH were significantly lower than those in patients whose cardiac arrest duration was under 5 min (P < 0.001, P < 0.001, P < 0.005 and P < 0.05, respectively). Conclusion TFTs are significantly altered in cardiac arrest induced by ACS. Changes in TFTs are even more pronounced in patients with longer periods of resuscitation. The changes in the surviving patients were characterized by euthyroid sick

  19. Cardiac Atrial Circadian Rhythms in PERIOD2::LUCIFERASE and per1:luc Mice: Amplitude and Phase Responses to Glucocorticoid Signaling and Medium Treatment

    PubMed Central

    Xi, Yang; Li, Lei; Duffield, Giles E.

    2012-01-01

    Circadian rhythms in cardiac function are apparent in e.g., blood pressure, heart rate, and acute adverse cardiac events. A circadian clock in heart tissue has been identified, but entrainment pathways of this clock are still unclear. We cultured tissues of mice carrying bioluminescence reporters of the core clock genes, period 1 or 2 (per1luc or PER2LUC) and compared in vitro responses of atrium to treatment with medium and a synthetic glucocorticoid (dexamethasone [DEX]) to that of the suprachiasmatic nucleus (SCN) and liver. We observed that PER2LUC, but not per1luc is rhythmic in atrial tissue, while both per1luc and PER2LUC exhibit rhythmicity in other cultured tissues. In contrast to the SCN and liver, both per1luc and PER2LUC bioluminescence amplitudes were increased in response to DEX treatment, and the PER2LUC amplitude response was dependent on the time of treatment. Large phase-shift responses to both medium and DEX treatments were observed in the atrium, and phase responses to medium treatment were not attributed to serum content but the treatment procedure itself. The phase-response curves of atrium to both DEX and medium treatments were found to be different to the liver. Moreover, the time of day of the culturing procedure itself influenced the phase of the circadian clock in each of the cultured tissues, but the magnitude of this response was uniquely large in atrial tissue. The current data describe novel entrainment signals for the atrial circadian clock and specifically highlight entrainment by mechanical treatment, an intriguing observation considering the mechanical nature of cardiac tissue. PMID:23110090

  20. An investigation of a hypothermic to ischemic ratio in patients following out-of-hospital cardiac arrest presenting with a shockable rhythm.

    PubMed

    Sawyer, Kelly N; Kurz, Michael C; Elswick, R K

    2014-06-01

    Targeted temperature management (TTM) improves outcome after out-of-hospital cardiac arrest (OHCA). We hypothesized that there may be a significant relationship between the dose of hypothermia, the time to return of spontaneous circulation (ROSC), and survival to discharge. Retrospective pilot investigation on 99 consecutive OHCA patients with initial shockable rhythm, surviving to admission, and undergoing TTM between 2008 and 2011. Dose of hypothermia was defined as the sum of the induction interval (time to target temperature [from ROSC to 33°C]); the controlled hypothermia interval (from reaching 33°C until rewarming); and the rewarming interval (from 33°C to 37°C). Time to ROSC was measured from pulselessness or 911 call time to ROSC. The ratio between the two was termed the hypothermic to ischemic ratio. Purposeful variable selection for logistic regression modeling was used to assess the influence of the hypothermic/ischemic ratio on survival. Odds ratios (OR) were used to examine the effects of predictor variables on survival. Of 99 patients, eight were excluded for deviation from protocol, death during protocol, or missing data. From the univariate models, survivors were more likely to be younger, have a shorter time to ROSC, and have a larger hypothermic/ischemic ratio. Survivors also had a nonsignificant trend toward a longer time to target temperature. In multivariable modeling, the hypothermic/ischemic ratio was the most significant predictor for survival (OR 2.161 [95% confidence interval 1.371, 3.404]). In this pilot study, the hypothermic to ischemic ratio was significantly associated with survival to discharge for patients with an initial shockable rhythm. Further investigation of the relationship between the dose of hypothermia and time to ROSC for postresuscitation TTM is needed. PMID:24679188

  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. Interference of GSM mobile phones with communication between Cardiac Rhythm Management devices and programmers: A combined in vivo and in vitro study.

    PubMed

    Huang, Dong; Dong, Zhi-Feng; Chen, Yan; Wang, Fa-Bin; Wei, Zhi; Zhao, Wen-Bin; Li, Shuai; Liu, Ming-Ya; Zhu, Wei; Wei, Meng; Li, Jing-Bo

    2015-07-01

    To investigate interference, and how to avoid it, by high-frequency electromagnetic fields (EMFs) of Global System for Mobile Communications (GSM) mobile phone with communication between cardiac rhythm management devices (CRMs) and programmers, a combined in vivo and in vitro testing was conducted. During in vivo testing, GSM mobile phones interfered with CRM-programmer communication in 33 of 65 subjects tested (50.8%). Losing ventricle sensing was representative in this study. In terms of clinical symptoms, only 4 subjects (0.6%) felt dizzy during testing. CRM-programmer communication recovered upon termination of mobile phone communication. During in vitro testing, electromagnetic interference by high-frequency (700-950 MHz) EMFs reproducibly occurred in duplicate testing in 18 of 20 CRMs (90%). During each interference, the pacing pulse signal on the programmer would suddenly disappear while the synchronous signal was normal on the amplifier-oscilloscope. Simulation analysis showed that interference by radiofrequency emitting devices with CRM-programmer communication may be attributed to factors including materials, excitation source distance, and implant depth. Results suggested that patients implanted with CRMs should not be restricted from using GSM mobile phones; however, CRMs should be kept away from high-frequency EMFs of GSM mobile phone during programming. PMID:25864643

  3. Relationship between pulmonary and cardiac abnormalities in sickle cell disease: implications for the management of patients

    PubMed Central

    Maioli, Maria Christina Paixão; Soares, Andrea Ribeiro; Bedirian, Ricardo; Alves, Ursula David; de Lima Marinho, Cirlene; Lopes, Agnaldo José

    2015-01-01

    Objective To evaluate the association between clinical, pulmonary, and cardiovascular findings in patients with sickle cell disease and, secondarily, to compare these findings between sickle cell anemia patients and those with other sickle cell diseases. Methods Fifty-nine adults were included in this cross-sectional study; 47 had sickle cell anemia, and 12 had other sickle cell diseases. All patients underwent pulmonary function tests, chest computed tomography, and echocardiography. Results Abnormalities on computed tomography, echocardiography, and pulmonary function tests were observed in 93.5%, 75.0%; and 70.2% of patients, respectively. A higher frequency of restrictive abnormalities was observed in patients with a history of acute chest syndrome (85% vs. 21.6%; p-value < 0.0001) and among patients with increased left ventricle size (48.2% vs. 22.2%; p-value = 0.036), and a higher frequency of reduced respiratory muscle strength was observed in patients with a ground-glass pattern (33.3% vs. 4.3%; p-value = 0.016). Moreover, a higher frequency of mosaic attenuation was observed in patients with elevated tricuspid regurgitation velocity (61.1% vs. 24%; p-value = 0.014). Compared to patients with other sickle cell diseases, sickle cell anemia patients had suffered increased frequencies of acute pain episodes, and acute chest syndrome, and exhibited mosaic attenuation on computed tomography, and abnormalities on echocardiography. Conclusion A significant interrelation between abnormalities of the pulmonary and cardiovascular systems was observed in sickle cell disease patients. Furthermore, the severity of the cardiopulmonary parameters among patients with sickle cell anemia was greater than that of patients with other sickle cell diseases. PMID:26969771

  4. Abnormal autonomic cardiac response to transient hypoxia in sickle cell anemia

    PubMed Central

    Sangkatumvong, S; Coates, T D; Khoo, M C K

    2010-01-01

    The objective of this study was to non-invasively assess cardiac autonomic control in subjects with sickle cell anemia (SCA) by tracking the changes in heart rate variability (HRV) that occur following brief exposure to a hypoxic stimulus. Five African–American SCA patients and seven healthy control subjects were recruited to participate in this study. Each subject was exposed to a controlled hypoxic stimulus consisting of five breaths of nitrogen. Time-varying spectral analysis of HRV was applied to estimate the cardiac autonomic response to the transient episode of hypoxia. The confounding effects of changes in respiration on the HRV spectral indices were reduced by using a computational model. A significant decrease in the parameters related to parasympathetic control was detected in the post-hypoxic responses of the SCA subjects relative to normal controls. The spectral index related to sympathetic activity, on the other hand, showed a tendency to increase the following hypoxic stimulation, but the change was not significant. This study suggests that there is some degree of cardiovascular autonomic dysfunction in SCA that is revealed by the response to transient hypoxia. PMID:18460753

  5. Robust algorithmic detection of the developed cardiac pathologies and emerging or transient abnormalities from short periods of RR data

    NASA Astrophysics Data System (ADS)

    Gavrishchaka, Valeriy V.; Senyukova, Olga

    2011-06-01

    Numerous research efforts and clinical testing have confirmed validity of heart rate variability (HRV) analysis as one of the cardiac diagnostics modalities. The majority of HRV analysis tools currently used in practice are based on linear indicators. Methods from nonlinear dynamics (NLD) provide more natural modeling framework for adaptive biological systems with multiple feedback loops. Compared to linear indicators, many NLD-based measures are much less sensitive to data artifacts and non-stationarity. However, majority of NLD measures require long time series for stable calculation. Similar restrictions also apply for linear indicators. Such requirements could drastically limit practical usability of HRV analysis in many applications, including express diagnostics, early indication of subtle directional changes during personalization of medical treatment, and robust detection of emerging or transient abnormalities. Recently we have illustrated that these challenges could be overcome by using classification framework based on boosting-like ensemble learning techniques that are capable of discovering robust meta-indicators from existing HRV measures and other incomplete empirical knowledge. In this paper we demonstrate universality of such meta-indicators and discuss operational details of their practical usage. Using such pathology examples as congestive heart failure (CHF) and arrhythmias, we show that classifiers trained on short RR segments (down to several minutes) could achieve reasonable classification accuracy (˜80-85% and higher). These indicators calculated from longer RR segments could be applicable for accurate diagnostics with classification accuracy approaching 100%. In addition, it is feasible to discover single "normal-abnormal" meta-classifier capable of detecting multiple abnormalities.

  6. 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

  7. Autonomic, locomotor and cardiac abnormalities in a mouse model of muscular dystrophy: targeting the renin-angiotensin system.

    PubMed

    Sabharwal, Rasna; Chapleau, Mark W

    2014-04-01

    New Findings What is the topic of this review? This symposium report summarizes autonomic, cardiac and skeletal muscle abnormalities in sarcoglycan-δ-deficient mice (Sgcd-/-), a mouse model of limb girdle muscular dystrophy, with emphasis on the roles of autonomic dysregulation and activation of the renin-angiotensin system at a young age. What advances does it highlight? The contributions of the autonomic nervous system and the renin-angiotensin system to the pathogenesis of muscular dystrophy are highlighted. Results demonstrate that autonomic dysregulation precedes and predicts later development of cardiac dysfunction in Sgcd-/- mice and that treatment of young Sgcd-/- mice with the angiotensin type 1 receptor antagonist losartan or with angiotensin-(1-7) abrogates the autonomic dysregulation, attenuates skeletal muscle pathology and increases spontaneous locomotor activity. Muscular dystrophies are a heterogeneous group of genetic muscle diseases characterized by muscle weakness and atrophy. Mutations in sarcoglycans and other subunits of the dystrophin-glycoprotein complex cause muscular dystrophy and dilated cardiomyopathy in animals and humans. Aberrant autonomic signalling is recognized in a variety of neuromuscular disorders. We hypothesized that activation of the renin-angiotensin system contributes to skeletal muscle and autonomic dysfunction in mice deficient in the sarcoglycan-δ (Sgcd) gene at a young age and that this early autonomic dysfunction contributes to the later development of left ventricular (LV) dysfunction and increased mortality. We demonstrated that young Sgcd-/- mice exhibit histopathological features of skeletal muscle dystrophy, decreased locomotor activity and severe autonomic dysregulation, but normal LV function. Autonomic regulation continued to deteriorate in Sgcd-/- mice with age and was accompanied by LV dysfunction and dilated cardiomyopathy at older ages. Autonomic dysregulation at a young age predicted later development of

  8. 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...

  9. 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

  10. 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

  11. 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

  12. Cardiac amyloidosis

    MedlinePlus

    ... the way electrical signals move through the heart (conduction system). This can lead to abnormal heart beats ( ... due to medication) Sick sinus syndrome Symptomatic cardiac conduction system disease (arrhythmias related to abnormal conduction of ...

  13. Non-invasive Mapping of Cardiac Arrhythmias.

    PubMed

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome). PMID:26072438

  14. Crossed pulmonary arteries: a report on 20 cases with an emphasis on the clinical features and the genetic and cardiac abnormalities.

    PubMed

    Babaoğlu, Kadir; Altun, Gürkan; Binnetoğlu, Köksal; Dönmez, Muhammed; Kayabey, Özlem; Anık, Yonca

    2013-01-01

    Crossed pulmonary arteries (CPAs) are a rare abnormality in which the ostium of the left pulmonary artery originates superior to the right pulmonary artery and to its right. Recognition of this rare pathology is important because it generally is accompanied by other congenital heart defects, extracardiac anomalies, and certain genetic problems. To date, only a few cases have been reported, and most of these cases have been associated with complex cardiac abnormalities. The authors detected 20 cases of CPA between June 2009 and November 2012 through their increasing awareness of this anomaly. Approximately 9,250 echocardiograms were performed during this period, and all of them also were checked for this anomaly. This report describes 20 cases of this CPA, with an emphasis on the clinical features and the genetic and cardiac abnormalities. The patients ranged in age from 1 day to 13 years at the time of the initial diagnosis. Four patients had complex cardiac pathologies such as tetralogy of Fallot, truncus arteriosus, transposition of the great arteries, and complete atrioventricular septal defect. Of the 20 patients, 11 had ventricular septal defects, and 12 had atrial septal defects. Pulmonary artery stenosis was detected in 12 (55 %) of the 20 patients. Aortic arch abnormalities such as interrupted aortic arch, right aortic arch, and coarctation of the aorta were detected in six patients. One patient had a left persistent superior vena cava. In 45 % of the cases, an associated genetic syndrome (DiGeorge-, Noonan-, Holt-Oram syndromes, vertebral, anal, cardiac, tracheal, esophageal, renal, limb anomalies [VACTERL] anomalies) was present. These syndromes were diagnosed based on their clinical features. Karyotype and fluorescent in situ hybridization (FISH) analyses for a 22q11 deletion were performed for 11 patients, with 10 patients found to have normal karyotype and FISH results. Only one patient had a 22q11 deletion. Six patients underwent successful operations

  15. 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.

  16. 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

  17. 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)

  18. Sonography in Hypotension and Cardiac Arrest (SHoC): Rates of Abnormal Findings in Undifferentiated Hypotension and During Cardiac Arrest as a Basis for Consensus on a Hierarchical Point of Care Ultrasound Protocol

    PubMed Central

    Milne, James; Lewis, David; Fraser, Jacqueline; Diegelmann, Laura; Olszynski, Paul; Stander, Melanie; Lamprecht, Hein

    2016-01-01

    Introduction Point of care ultrasound (PoCUS) has become an established tool in the initial management of patients with undifferentiated hypotension. Current established protocols (RUSH and ACES) were developed by expert user opinion, rather than objective, prospective data. PoCUS also provides invaluable information during resuscitation efforts in cardiac arrest by determining presence/absence of cardiac activity and identifying reversible causes such as pericardial tamponade. There is no agreed guideline on how to safely and effectively incorporate PoCUS into the advanced cardiac life support (ACLS) algorithm. We wished to report disease incidence as a basis to develop a hierarchical approach to PoCUS in hypotension and during cardiac arrest. Methods We summarized the recorded incidence of PoCUS findings from the initial cohort during the interim analysis of two prospective studies. We propose that this will form the basis for developing a modified Delphi approach incorporating this data to obtain the input of a panel of international experts associated with five professional organizations led by the International Federation of Emergency Medicine (IFEM). The modified Delphi tool will be developed to reach an international consensus on how to integrate PoCUS for hypotensive emergency department patients as well as into cardiac arrest algorithms. Results Rates of abnormal PoCUS findings from 151 patients with undifferentiated hypotension included left ventricular dynamic changes (43%), IVC abnormalities (27%), pericardial effusion (16%), and pleural fluid (8%). Abdominal pathology was rare (fluid 5%, AAA 2%). During cardiac arrest there were no pericardial effusions, however abnormalities of ventricular contraction (45%) and valvular motion (39%) were common among the 43 patients included. Conclusions A prospectively collected disease incidence-based hierarchy of scanning can be developed based on the reported findings. This will inform an international consensus

  19. 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

  20. Enabling microscale and nanoscale approaches for bioengineered cardiac tissue.

    PubMed

    Chan, Vincent; Raman, Ritu; Cvetkovic, Caroline; Bashir, Rashid

    2013-03-26

    In this issue of ACS Nano, Shin et al. present their finding that the addition of carbon nanotubes (CNT) in gelatin methacrylate (GelMA) results in improved functionality of bioengineered cardiac tissue. These CNT-GelMA hybrid materials demonstrate cardiac tissue with enhanced electrophysiological performance; improved mechanical integrity; better cell adhesion, viability, uniformity, and organization; increased beating rate and lowered excitation threshold; and protective effects against cardio-inhibitory and cardio-toxic drugs. In this Perspective, we outline recent progress in cardiac tissue engineering and prospects for future development. Bioengineered cardiac tissues can be used to build "heart-on-a-chip" devices for drug safety and efficacy testing, fabricate bioactuators for biointegrated robotics and reverse-engineered life forms, treat abnormal cardiac rhythms, and perhaps one day cure heart disease with tissue and organ transplants. PMID:23527748

  1. Predicting the risk of sudden cardiac death.

    PubMed

    Lerma, Claudia; Glass, Leon

    2016-05-01

    Sudden cardiac death (SCD) is the result of a change of cardiac activity from normal (typically sinus) rhythm to a rhythm that does not pump adequate blood to the brain. The most common rhythms leading to SCD are ventricular tachycardia (VT) or ventricular fibrillation (VF). These result from an accelerated ventricular pacemaker or ventricular reentrant waves. Despite significant efforts to develop accurate predictors for the risk of SCD, current methods for risk stratification still need to be improved. In this article we briefly review current approaches to risk stratification. Then we discuss the mathematical basis for dynamical transitions (called bifurcations) that may lead to VT and VF. One mechanism for transition to VT or VF involves a perturbation by a premature ventricular complex (PVC) during sinus rhythm. We describe the main mechanisms of PVCs (reentry, independent pacemakers and abnormal depolarizations). An emerging approach to risk stratification for SCD involves the development of individualized dynamical models of a patient based on measured anatomy and physiology. Careful analysis and modelling of dynamics of ventricular arrhythmia on an individual basis will be essential in order to improve risk stratification for SCD and to lay a foundation for personalized (precision) medicine in cardiology. PMID:26660287

  2. 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

  3. Fetal Arrhythmias Associated with Cardiac Rhabdomyomas

    PubMed Central

    Wacker-Gussmann, Annette; Strasburger, Janette F; Cuneo, Bettina; Wiggins, Delonia; Gotteiner, Nina; Wakai, Ronald T

    2014-01-01

    Background Primary heart tumors in fetuses are rare and mainly represent rhabdomyomas. The tumors have a variable expression and can be associated with arrhythmias, including both wide and narrow QRS tachycardia. Although multiple Doppler techniques exist to assess fetal heart rhythm, it can be difficult to record precise electrophysiological pathologies in fetal life. Objective Investigations defining precise electrophysiological diagnosis were performed using fetal magnetocardiography (fMCG). Methods In addition to routine fetal echocardiography, fMCG was used to investigate electrophysiologic rhythm patterns in a series of 10 fetuses with cardiac rhabdomyomas. Results The mean gestational age of the fetuses was 28.6 weeks (SD ± 4.7 weeks). The multiple rhabdomyomas were mainly located in the right and left ventricles as well as around the AV groove. Arrhythmias or conduction abnormalities were diagnosed in all 10 patients, although only six of them were referred due to that indication. Remarkably, 80% (8/10) had associated Wolff-Parkinson-White pre-excitation. In addition, we found prominent p waves in four fetuses. Conclusion In fetuses with rhabdomyomas, a disease where rhythm pathology is common, precise electrophysiological diagnosis can now be made by fMCG. fMCG is complimentary to echocardiography for rhythm assessment, and can detect conduction abnormalities that are not possible to diagnose prenatally with M-mode or pulsed Doppler ultrasound. Risk factor assessment using fMCG can support pregnancy management and post-natal treatment and follow-up. PMID:24333285

  4. 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

  5. Noninvasive assessment of cardiac abnormalities in experimental autoimmune myocarditis by magnetic resonance microscopy imaging in the mouse.

    PubMed

    Massilamany, Chandirasegaran; Khalilzad-Sharghi, Vahid; Gangaplara, Arunakumar; Steffen, David; Othman, Shadi F; Reddy, Jay

    2014-01-01

    Myocarditis is an inflammation of the myocardium, but only -10% of those affected show clinical manifestations of the disease. To study the immune events of myocardial injuries, various mouse models of myocarditis have been widely used. This study involved experimental autoimmune myocarditis (EAM) induced with cardiac myosin heavy chain (Myhc)-α 334-352 in A/J mice; the affected animals develop lymphocytic myocarditis but with no apparent clinical signs. In this model, the utility of magnetic resonance microscopy (MRM) as a non-invasive modality to determine the cardiac structural and functional changes in animals immunized with Myhc-α 334-352 is shown. EAM and healthy mice were imaged using a 9.4 T (400 MHz) 89 mm vertical core bore scanner equipped with a 4 cm millipede radio-frequency imaging probe and 100 G/cm triple axis gradients. Cardiac images were acquired from anesthetized animals using a gradient-echo-based cine pulse sequence, and the animals were monitored by respiration and pulse oximetry. The analysis revealed an increase in the thickness of the ventricular wall in EAM mice, with a corresponding decrease in the interior diameter of ventricles, when compared with healthy mice. The data suggest that morphological and functional changes in the inflamed hearts can be non-invasively monitored by MRM in live animals. In conclusion, MRM offers an advantage of assessing the progression and regression of myocardial injuries in diseases caused by infectious agents, as well as response to therapies. PMID:24998332

  6. Abnormal interactions of calsequestrin with the ryanodine receptor calcium release channel complex linked to exercise-induced sudden cardiac death.

    PubMed

    Terentyev, Dmitry; Nori, Alessandra; Santoro, Massimo; Viatchenko-Karpinski, Serge; Kubalova, Zuzana; Gyorke, Inna; Terentyeva, Radmila; Vedamoorthyrao, Srikanth; Blom, Nico A; Valle, Giorgia; Napolitano, Carlo; Williams, Simon C; Volpe, Pompeo; Priori, Silvia G; Gyorke, Sandor

    2006-05-12

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial arrhythmogenic disorder associated with mutations in the cardiac ryanodine receptor (RyR2) and cardiac calsequestrin (CASQ2) genes. Previous in vitro studies suggested that RyR2 and CASQ2 interact as parts of a multimolecular Ca(2+)-signaling complex; however, direct evidence for such interactions and their potential significance to myocardial function remain to be determined. We identified a novel CASQ2 mutation in a young female with a structurally normal heart and unexplained syncopal episodes. This mutation results in the nonconservative substitution of glutamine for arginine at amino acid 33 of CASQ2 (R33Q). Adenoviral-mediated expression of CASQ2(R33Q) in adult rat myocytes led to an increase in excitation-contraction coupling gain and to more frequent occurrences of spontaneous propagating (Ca2+ waves) and local Ca2+ signals (sparks) with respect to control cells expressing wild-type CASQ2 (CASQ2WT). As revealed by a Ca2+ indicator entrapped inside the sarcoplasmic reticulum (SR) of permeabilized myocytes, the increased occurrence of spontaneous Ca2+ sparks and waves was associated with a dramatic decrease in intra-SR [Ca2+]. Recombinant CASQ2WT and CASQ2R33Q exhibited similar Ca(2+)-binding capacities in vitro; however, the mutant protein lacked the ability of its WT counterpart to inhibit RyR2 activity at low luminal [Ca2+] in planar lipid bilayers. We conclude that the R33Q mutation disrupts interactions of CASQ2 with the RyR2 channel complex and impairs regulation of RyR2 by luminal Ca2+. These results show that intracellular Ca2+ cycling in normal heart relies on an intricate interplay of CASQ2 with the proteins of the RyR2 channel complex and that disruption of these interactions can lead to cardiac arrhythmia. PMID:16601229

  7. Mitochondria-targeted ROS scavenger improves post-ischemic recovery of cardiac function and attenuates mitochondrial abnormalities in aged rats

    PubMed Central

    Escobales, Nelson; Nuñez, Rebeca E.; Jang, Sehwan; Parodi-Rullan, Rebecca; Ayala-Peña, Sylvette; Sacher, Joshua R.; Skoda, Erin M.; Wipf, Peter; Frontera, Walter; Javadov, Sabzali

    2014-01-01

    Mitochondria-generated reactive oxygen species (ROS) play a crucial role in the pathogenesis of aging and age-associated diseases. In this study, we evaluated the effects of XJB-5-131 (XJB), a mitochondria-targeted ROS and electron scavenger, on cardiac resistance to ischemia-reperfusion (IR)-induced oxidative stress in aged rats. Male adult (5-month old, n=17) and aged (29-month old, n=19) Fischer Brown Norway (F344/BN) rats were randomly assigned to the following groups: adult (A), adult+XJB (AX), aged (O), and aged+XJB (OX). XJB was administered 3 times per week (3 mg/kg body weight, IP) for four weeks. At the end of the treatment period, cardiac function was continuously monitored in excised hearts using the Langendorff technique for 30 min, followed by 20-min of global ischemia, and 60-min reperfusion. XJB improved post-ischemic recovery of aged hearts, as evidenced by greater left ventricular developed-pressures and rate-pressure products than the untreated, aged-matched group. The state 3 respiration rates at complexes I, II and IV of mitochondria isolated from XJB-treated aged hearts were 57% (P<0.05), 25% (P<0.05) and 28% (P<0.05), respectively, higher than controls. Ca2+-induced swelling, an indicator of permeability transition pore opening, was reduced in mitochondria of XJB-treated aged rats. In addition, XJB significantly attenuated the H2O2-induced depolarization of the mitochondrial inner membrane as well as total and mitochondrial ROS levels in cultured cardiomyocytes. This study underlines the importance of mitochondrial ROS in aging-induced cardiac dysfunction and suggests that targeting mitochondrial ROS may be an effective therapeutic approach to protect the aged heart against IR injury. PMID:25451170

  8. Mitochondria-targeted ROS scavenger improves post-ischemic recovery of cardiac function and attenuates mitochondrial abnormalities in aged rats.

    PubMed

    Escobales, Nelson; Nuñez, Rebeca E; Jang, Sehwan; Parodi-Rullan, Rebecca; Ayala-Peña, Sylvette; Sacher, Joshua R; Skoda, Erin M; Wipf, Peter; Frontera, Walter; Javadov, Sabzali

    2014-12-01

    Mitochondria-generated reactive oxygen species (ROS) play a crucial role in the pathogenesis of aging and age-associated diseases. In this study, we evaluated the effects of XJB-5-131 (XJB), a mitochondria-targeted ROS and electron scavenger, on cardiac resistance to ischemia-reperfusion (IR)-induced oxidative stress in aged rats. Male adult (5-month old, n=17) and aged (29-month old, n=19) Fischer Brown Norway (F344/BN) rats were randomly assigned to the following groups: adult (A), adult+XJB (AX), aged (O), and aged+XJB (OX). XJB was administered 3 times per week (3mg/kg body weight, IP) for four weeks. At the end of the treatment period, cardiac function was continuously monitored in excised hearts using the Langendorff technique for 30 min, followed by 20 min of global ischemia, and 60-min reperfusion. XJB improved post-ischemic recovery of aged hearts, as evidenced by greater left ventricular developed-pressures and rate-pressure products than the untreated, aged-matched group. The state 3 respiration rates at complexes I, II and IV of mitochondria isolated from XJB-treated aged hearts were 57% (P<0.05), 25% (P<0.05) and 28% (P<0.05), respectively, higher than controls. Ca(2+)-induced swelling, an indicator of permeability transition pore opening, was reduced in the mitochondria of XJB-treated aged rats. In addition, XJB significantly attenuated the H2O2-induced depolarization of the mitochondrial inner membrane as well as the total and mitochondrial ROS levels in cultured cardiomyocytes. This study underlines the importance of mitochondrial ROS in aging-induced cardiac dysfunction and suggests that targeting mitochondrial ROS may be an effective therapeutic approach to protect the aged heart against IR injury. PMID:25451170

  9. 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

  10. Association of interatrial septal abnormalities with cardiac impulse conduction disorders in adult patients: experience from a tertiary center in Kosovo

    PubMed Central

    Bakalli, Aurora; Pllana, Ejup; Koçinaj, Dardan; Bekteshi, Tefik; Dragusha, Gani; Gashi, Masar; Musliu, Nebih; Gashi, Zaim

    2011-01-01

    Interatrial septal disorders, which include: atrial septal defect, patent foramen ovale and atrial septal aneurysm, are frequent congenital anomalies found in adult patients. Early detection of these anomalies is important to prevent their hemodynamic and/or thromboembolic consequences. The aims of this study were: to assess the association between impulse conduction disorders and anomalies of interatrial septum; to determine the prevalence of different types of interatrial septum abnormalities; to assess anatomic, hemodynamic, and clinical consequences of interatrial septal pathologies. Fifty-three adult patients with impulse conduction disorders and patients without ECG changes but with signs of interatrial septal abnormalities, who were referred to our center for echocardiography, were included in a prospective transesophageal echocardiography study. Interatrial septal anomalies were detected in around 85% of the examined patients. Patent foramen ovale was encountered in 32% of the patients, and in combination with atrial septal aneurysm in an additional 11.3% of cases. Atrial septal aneurysm and atrial septal defect were diagnosed with equal frequency in 20.7% of our study population. Impulse conduction disorders were significantly more suggestive of interatrial septal anomalies than clinical signs and symptoms observed in our patients (84.91% vs 30.19%, P=0.002). Right bundle branch block was the most frequent impulse conduction disorder, found in 41 (77.36%) cases. We conclude that interatrial septal anomalies are highly associated with impulse conduction disorders, particularly with right bundle branch block. Impulse conduction disorders are more indicative of interatrial septal abnormalities in earlier stages than can be understood from the patient’s clinical condition. PMID:21977304

  11. Association of interatrial septal abnormalities with cardiac impulse conduction disorders in adult patients: experience from a tertiary center in Kosovo.

    PubMed

    Bakalli, Aurora; Pllana, Ejup; Koçinaj, Dardan; Bekteshi, Tefik; Dragusha, Gani; Gashi, Masar; Musliu, Nebih; Gashi, Zaim

    2011-01-01

    INTERATRIAL SEPTAL DISORDERS, WHICH INCLUDE: atrial septal defect, patent foramen ovale and atrial septal aneurysm, are frequent congenital anomalies found in adult patients. Early detection of these anomalies is important to prevent their hemodynamic and/or thromboembolic consequences. The aims of this study were: to assess the association between impulse conduction disorders and anomalies of interatrial septum; to determine the prevalence of different types of interatrial septum abnormalities; to assess anatomic, hemodynamic, and clinical consequences of interatrial septal pathologies. Fifty-three adult patients with impulse conduction disorders and patients without ECG changes but with signs of interatrial septal abnormalities, who were referred to our center for echocardiography, were included in a prospective transesophageal echocardiography study. Interatrial septal anomalies were detected in around 85% of the examined patients. Patent foramen ovale was encountered in 32% of the patients, and in combination with atrial septal aneurysm in an additional 11.3% of cases. Atrial septal aneurysm and atrial septal defect were diagnosed with equal frequency in 20.7% of our study population. Impulse conduction disorders were significantly more suggestive of interatrial septal anomalies than clinical signs and symptoms observed in our patients (84.91% vs 30.19%, P=0.002). Right bundle branch block was the most frequent impulse conduction disorder, found in 41 (77.36%) cases. We conclude that interatrial septal anomalies are highly associated with impulse conduction disorders, particularly with right bundle branch block. Impulse conduction disorders are more indicative of interatrial septal abnormalities in earlier stages than can be understood from the patient's clinical condition. PMID:21977304

  12. Protective effect of oleanolic acid on oxidative injury and cellular abnormalities in doxorubicin induced cardiac toxicity in rats.

    PubMed

    Goyal, Sameer N; Mahajan, Umesh B; Chandrayan, Govind; Kumawat, Vivek S; Kamble, Sarika; Patil, Pradip; Agrawal, Yogeeta O; Patil, Chandragouda R; Ojha, Shreesh

    2016-01-01

    The prevention of doxorubicin (Dox) induced cardiotoxicity may be co-operative to recover future Dox treatment. The aim of this study was to explore the cardioprotective effects of oleanolic acid (OA), an antioxidant agent, on Dox induced cardiotoxicity. OA is a triterpenoid compound, which exist widely in plant kingdom in free acid form or as a glycosidic triterpenoids saponins. Cardiotoxicity was induced in Wistar rats with single intravenous injection of doxorubicin at dose of 67.75 mg/kg i.v for 48 hrs. At 12 hrs of interval following Dox administration the cardioprotective effect of OA (1.5 mg/kg, i.v.) and Amifostine (AMF) (90 mg/kg i.v., single dose prior 30 min) were evaluated. Induction of cardiotoxicity was confirmed by increase in systolic, diastolic, mean arterial pressures, maximal positive rate of developed left ventricular pressure (+LVdP/dtmax, an indicator of myocardial contraction), maximal negative rate of developed left ventricular pressure (-LVdP/dtmax, a meter of myocardial relaxation) and an increase in left ventricular end-diastolic pressure (LVEDP, a marker of pre-load). Cardiac markers in such as CK-MB, LDH and alterations in ECG. Dox administration showed alteration in Biochemical parameters and endogenous antioxidants. Administration of OA Showed maximal protection against Dox induced cardiac toxicity as observed by reduction in blood pressure, prevention of left ventricular function and attenuation of biochemical and antioxidant parameters. Based on the findings, its concluded that OA can be used as an adjuvant with Dox therapy in treating cancers. PMID:27069540

  13. Protective effect of oleanolic acid on oxidative injury and cellular abnormalities in doxorubicin induced cardiac toxicity in rats

    PubMed Central

    Goyal, Sameer N; Mahajan, Umesh B; Chandrayan, Govind; Kumawat, Vivek S; Kamble, Sarika; Patil, Pradip; Agrawal, Yogeeta O; Patil, Chandragouda R; Ojha, Shreesh

    2016-01-01

    The prevention of doxorubicin (Dox) induced cardiotoxicity may be co-operative to recover future Dox treatment. The aim of this study was to explore the cardioprotective effects of oleanolic acid (OA), an antioxidant agent, on Dox induced cardiotoxicity. OA is a triterpenoid compound, which exist widely in plant kingdom in free acid form or as a glycosidic triterpenoids saponins. Cardiotoxicity was induced in Wistar rats with single intravenous injection of doxorubicin at dose of 67.75 mg/kg i.v for 48 hrs. At 12 hrs of interval following Dox administration the cardioprotective effect of OA (1.5 mg/kg, i.v.) and Amifostine (AMF) (90 mg/kg i.v., single dose prior 30 min) were evaluated. Induction of cardiotoxicity was confirmed by increase in systolic, diastolic, mean arterial pressures, maximal positive rate of developed left ventricular pressure (+LVdP/dtmax, an indicator of myocardial contraction), maximal negative rate of developed left ventricular pressure (-LVdP/dtmax, a meter of myocardial relaxation) and an increase in left ventricular end-diastolic pressure (LVEDP, a marker of pre-load). Cardiac markers in such as CK-MB, LDH and alterations in ECG. Dox administration showed alteration in Biochemical parameters and endogenous antioxidants. Administration of OA Showed maximal protection against Dox induced cardiac toxicity as observed by reduction in blood pressure, prevention of left ventricular function and attenuation of biochemical and antioxidant parameters. Based on the findings, its concluded that OA can be used as an adjuvant with Dox therapy in treating cancers. PMID:27069540

  14. 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

  15. Mesenteric lymph from rats with trauma-hemorrhagic shock causes abnormal cardiac myocyte function and induces myocardial contractile dysfunction

    PubMed Central

    Sambol, Justin T.; Lee, Marlon A.; Jiang, Mingshan; Dosi, Garima; Dong, Wei; Deitch, Edwin A.

    2011-01-01

    Myocardial contractile dysfunction develops following trauma-hemorrhagic shock (T/HS). We have previously shown that, in a rat fixed pressure model of T/HS (mean arterial pressure of 30–35 mmHg for 90 min), mesenteric lymph duct ligation before T/HS prevented T/HS-induced myocardial contractile depression. To determine whether T/HS lymph directly alters myocardial contractility, we examined the functional effects of physiologically relevant concentrations of mesenteric lymph collected from rats undergoing trauma-sham shock (T/SS) or T/HS on both isolated cardiac myocytes and Langendorff-perfused whole hearts. Acute application of T/HS lymph (0.1–2%), but not T/SS lymph, induced dual inotropic effects on myocytes with an immediate increase in the amplitude of cell shortening (1.4 ± 0.1-fold) followed by a complete block of contraction. Similarly, T/HS lymph caused dual, positive and negative effects on cellular Ca2+ transients. These effects were associated with changes in the electrophysiological properties of cardiac myocytes; T/HS lymph initially prolonged the action potential duration (action potential duration at 90% repolarization, 3.3 ± 0.4-fold), and this was followed by a decrease in the plateau potential and membrane depolarization. Furthermore, intravenous infusion of T/HS lymph, but not T/SS lymph, caused myocardial contractile dysfunction at 24 h after injection, which mimicked actual T/HS-induced changes; left ventricular developed pressure (LVDP) and the maximal rate of LVDP rise and fall (±dP/dtmax) were decreased and inotropic response to Ca2+ was blunted. However, the contractile responsiveness to β-adrenergic receptor stimulation in the T/HS lymph-infused hearts remained unchanged. These results suggest that T/HS lymph directly causes negative inotropic effects on the myocardium and that T/HS lymph-induced changes in myocyte function are likely to contribute to the development of T/HS-induced myocardial dysfunction. PMID:21700891

  16. Association between FGF23, α-Klotho, and Cardiac Abnormalities among Patients with Various Chronic Kidney Disease Stages

    PubMed Central

    Tanaka, Suguru; Fujita, Shu-ichi; Kizawa, Shun; Morita, Hideaki; Ishizaka, Nobukazu

    2016-01-01

    Background Several experimental studies have demonstrated that fibroblast growth factor 23 (FGF23) may induce myocardial hypertrophy via pathways independent of α-Klotho, its co-factor in the induction of phosphaturia. On the other hand, few studies have clearly demonstrated the relationship between FGF23 level and left ventricular hypertrophy among subjects without chronic kidney disease (CKD; i.e., CKD stage G1 or G2). Purpose To investigate the data from 903 patients admitted to the cardiology department with various degrees of renal function, including 234 patients with CKD stage G1/G2. Methods and Results Serum levels of full-length FGF23 and α-Klotho were determined by enzyme immunoassay. After adjustment for sex, age, and estimated glomerular filtration rate (eGFR), the highest FGF23 tertile was significantly associated with left ventricular hypertrophy among patients with CKD stage G1/G2 and those with CKD stage G3a/G3b/G4 as compared with the lowest FGF23 tertile, and the association retained significance after further adjustment for serum levels of corrected calcium, inorganic phosphate, and C-reactive protein, as well as diuretic use, history of hypertension, and systolic blood pressure. FGF23 was also associated with low left ventricular ejection fraction among patients with CKD stage G1/G2 and those with CKD stage G3a/G3b/G4 after adjusting for age, sex, eGFR, corrected calcium, and inorganic phosphate. On the other hand, compared with the highest α-Klotho tertile, the lowest α-Klotho tertile was associated with left ventricular hypertrophy and systolic dysfunction only among patients with CKD stage G3b and stage G3a, respectively. Conclusions An association between FGF23 and cardiac hypertrophy and systolic dysfunction was observed among patients without CKD as well as those with CKD after multivariate adjustment. However, the association between α-Klotho and cardiac hypertrophy and systolic dysfunction was significant only among patients with

  17. Abnormalities in Cardiac Structure and Function in Adults with Sickle Cell Disease are not Associated with Pulmonary Hypertension

    PubMed Central

    Knight-Perry, Jessica E.; de las Fuentes, Lisa; Waggoner, Alan D.; Hoffmann, Raymond G.; Blinder, Morey A.; Dávila-Román, Victor G.; Field, Joshua J.

    2011-01-01

    Background In sickle cell disease (SCD), pulmonary hypertension (assessed by tricuspid regurgitant jet [TRJ] velocity ≥ 2.5 m/s) is associated with increased mortality. The relationships between TRJ velocity, left ventricular (LV) and right ventricular (RV) systolic and diastolic function (i.e., relaxation and compliance) have not been well characterized in SCD. Design and Methods Prospective study of 53 ambulatory SCD adults (age, mean: 34 years; range 21-65 years) and 33 African American controls to define the relationship between LV and RV function and TRJ velocity by use of echocardiography. Results SCD subjects had larger left and right atrial volumes and increased LV mass compared to controls. When SCD cases were compared to controls, LV and RV relaxation (i.e., E’) were similar. Among SCD subjects, pulmonary hypertension (TRJ ≥ 2.5 m/s) was present in 40% of cases. Higher TRJ velocity was correlated with larger LA volumes and areas in SCD cases. Additionally, some measures of LV (peak A, lateral and septal annulus E/E’) and RV compliance (TV E/E’) were correlated with TRJ velocity. No other measures of LV/RV systolic function or LV diastolic function (i.e., relaxation and compliance) were associated with TRJ velocity. Conclusions Ambulatory adults with SCD exhibited structural (i.e., LV and RV chamber enlargement) and functional (i.e., higher surrogate measures of LV and RV filling pressure) abnormalities compared to the control group. In SCD subjects, few abnormalities of LV and RV structure/function were associated with TRJ velocity. PMID:21873028

  18. Bioptic Study of Left and Right Atrial Interstitium in Cardiac Patients with and without Atrial Fibrillation: Interatrial but Not Rhythm-Based Differences

    PubMed Central

    Smorodinova, Natalia; Lantová, Lucie; Bláha, Martin; Melenovský, Vojtěch; Hanzelka, Jan; Pirk, Jan; Kautzner, Josef; Kučera, Tomáš

    2015-01-01

    One of the generally recognized factors contributing to the initiation and maintenance of atrial fibrillation (AF) is structural remodeling of the myocardium that affects both atrial cardiomyocytes as well as interstitium. The goal of this study was to characterize morphologically and functionally interstitium of atria in patients with AF or in sinus rhythm (SR) who were indicated to heart surgery. Patient population consisted of 46 subjects (19 with long-term persistent AF, and 27 in SR) undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atria were examined using immunohistochemistry to visualize and quantify collagen I, collagen III, elastin, desmin, smooth muscle actin, endothelium and Vascular Endothelial Growth Factor (VEGF). The content of interstitial elastin, collagen I, and collagen III in atrial tissue was similar in AF and SR groups. However, the right atrium was more than twofold more abundant in elastin as compared with the left atrium and similar difference was found for collagen I and III. The right atrium showed also higher VEGF expression and lower microvascular density as compared to the left atrium. No significant changes in atrial extracellular matrix fiber content, microvascular density and angiogenic signaling, attributable to AF, were found in this cohort of patients with structural heart disease. This finding suggests that interstitial fibrosis and other morphological changes in atrial tissue are rather linked to structural heart disease than to AF per se. Significant regional differences in interstitial structure between right and left atrium is a novel observation that deserves further investigation. PMID:26067062

  19. Effects of metabolic and myocardial microcirculatory abnormalities on the pathogenesis of cardiac autonomic neuropathy in type 2 diabetes mellitus: A prospective study in Japanese patients*

    PubMed Central

    Komori, Hiromi

    2005-01-01

    Background: In diabetic patients, cardiac autonomic neuropathy is an important factor affecting prognosis. Whether this condition in diabetic patients is caused directly by neurovisceral metabolic disorder and/or indirectly by micro circulation remains to be clarified. Objective: The aim of this study was to determine whether cardiac sympathetic nerve dysfunction can be detected using adenosine triphosphate (ATP) testing, while also investigating the effects of metabolic and/or myocardial microcirculatory abnormalities on the pathogenesis of cardiac autonomic nerve dysfunction in patients with type 2 diabetes mellitus (DM-2) in Japan. Methods: This prospective study was performed at the Division of Diabetology Department of Internal Medicine, Toho University, Ohashi Hospital, Tokyo, Japan. Patients aged ≥ 18 years with DM-2 with no abnormalities on electrocardiography (ECG) or echocardiography were enrolled. An ATP thallium (Tl)-201 myocardial scintigraphy test (ATP test) and iodine (I)-123 metaiodobenzylguanidine (MIBG) scintigraphy were performed. ATP was administered by continuous IV infusion over 6 minutes at 0.16 mg/kg · min. Five minutes after the ATP infusion was started, T1-201 111 MBq IV was administered. Single-photon emission computed tomography (SPECT) imaging was begun immediately after the end of ATP infusion and was completed 3 hours after stress to show washout from stress to rest. I-123 MIBG 111 MBq IV was administered. A planar image from the front side and a SPECT image (early phase) was obtained 15 to 30 minutes later. After 3 hours, a planar image from the front side and a SPECT image (late phase) were obtained to show washout from stress to rest. The mean TI washout rate (ATP-WR) and heart-to-mediastinum (H/M) ratio in the late-phase scintigraphic images and the washout rate of MIBG (MIBG-WR) in the left ventricle was determined. The correlations of these measurements with the mean values of glycosylated hemoglobin (HbA1c) and fasting

  20. 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 ...

  1. 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

  2. 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

  3. [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

  4. 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

  5. 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

  6. 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

  7. [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

  8. Complex Dynamics of the Cardiac Rhythms

    NASA Astrophysics Data System (ADS)

    Filippi, S.; Cherubini, C.

    Many biological systems which appear complex both in space and time and result still not understood, require new theoretical approaches for their nonlinear dynamics. In particular we focus here on the theoretical analysis of the underlying mechanisms of heart dynamics. This could clarify the (apparently) chaotic behavior of the normal heart-beat and especially the control of the bifurcations of dynamics arising in situ- ations of disease. The principal target is to find a possible clear distinction between normal and pathological regimes. A discussion of Complex Ginzburg-Landau equation can give useful hints to this aim.

  9. Rapidly detecting disorder in rhythmic biological signals: A spectral entropy measure to identify cardiac arrhythmias

    NASA Astrophysics Data System (ADS)

    Staniczenko, Phillip P. A.; Lee, Chiu Fan; Jones, Nick S.

    2009-01-01

    We consider the use of a running measure of power spectrum disorder to distinguish between the normal sinus rhythm of the heart and two forms of cardiac arrhythmia: atrial fibrillation and atrial flutter. This spectral entropy measure is motivated by characteristic differences in the power spectra of beat timings during the three rhythms. We plot patient data derived from ten-beat windows on a “disorder map” and identify rhythm-defining ranges in the level and variance of spectral entropy values. Employing the spectral entropy within an automatic arrhythmia detection algorithm enables the classification of periods of atrial fibrillation from the time series of patients’ beats. When the algorithm is set to identify abnormal rhythms within 6s , it agrees with 85.7% of the annotations of professional rhythm assessors; for a response time of 30s , this becomes 89.5%, and with 60s , it is 90.3%. The algorithm provides a rapid way to detect atrial fibrillation, demonstrating usable response times as low as 6s . Measures of disorder in the frequency domain have practical significance in a range of biological signals: the techniques described in this paper have potential application for the rapid identification of disorder in other rhythmic signals.

  10. 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

  11. 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 ...

  12. 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.

  13. 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.

  14. Cardiac Sarcoidosis.

    PubMed

    Birnie, David H; Nery, Pablo B; Ha, Andrew C; Beanlands, Rob S B

    2016-07-26

    Clinically manifest cardiac involvement occurs in perhaps 5% of patients with sarcoidosis. The 3 principal manifestations of cardiac sarcoidosis (CS) are conduction abnormalities, ventricular arrhythmias, and heart failure. An estimated 20% to 25% of patients with pulmonary/systemic sarcoidosis have asymptomatic cardiac involvement (clinically silent disease). In 2014, the first international guideline for the diagnosis and management of CS was published. In patients with clinically manifest CS, the extent of left ventricular dysfunction seems to be the most important predictor of prognosis. There is controversy in published reports as to the outcome of patients with clinically silent CS. Despite a paucity of data, immunosuppression therapy (primarily with corticosteroids) has been advocated for the treatment of clinically manifest CS. Device therapy, primarily with implantable cardioverter-defibrillators, is often recommended for patients with clinically manifest disease. PMID:27443438

  15. 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 ...

  16. 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…

  17. 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…

  18. 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

  19. 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…

  20. 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

  1. Structural Defects Lead to Dynamic Entrapment in Cardiac Electrophysiology

    PubMed Central

    Bates, Oliver R. J.; Suki, Bela; Spector, Peter S.; Bates, Jason H. T.

    2015-01-01

    Biological networks are typically comprised of many parts whose interactions are governed by nonlinear dynamics. This potentially imbues them with the ability to support multiple attractors, and therefore to exhibit correspondingly distinct patterns of behavior. In particular, multiple attractors have been demonstrated for the electrical activity of the diseased heart in situations where cardioversion is able to convert a reentrant arrhythmia to a stable normal rhythm. Healthy hearts, however, are typically resilient to abnormal rhythms. This raises the question as to how a healthy cardiac cell network must be altered so that it can support multiple distinct behaviors. Here we demonstrate how anatomic defects can give rise to multi-stability in the heart as a function of the electrophysiological properties of the cardiac tissue and the timing of activation of ectopic foci. This leads to a form of hysteretic behavior, which we call dynamic entrapment, whereby the heart can become trapped in aberrant attractor as a result of a transient change in tissue properties. We show that this can lead to a highly inconsistent relationship between clinical symptoms and underlying pathophysiology, which raises the possibility that dynamic entrapment may underlie other forms of chronic idiopathic illness. PMID:25756656

  2. 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.

  3. 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

  4. Utility of noninvasive, mobile, continuous outpatient rhythm monitoring to diagnose seizure-related arrhythmias.

    PubMed

    Driver, Kevin; Gilliam, Frank; Dizon, Jose; Whang, William; Ehlert, Frederick; Hickey, Kathleen; Garan, Hasan; Biviano, Angelo B

    2009-07-01

    The identification of patients with a diagnosis of seizure disorder who are also at risk for clinically significant bradycardia and/or tachycardia may require long-term cardiac rhythm monitoring. Noninvasive, continuous, outpatient cardiac rhythm monitoring may be useful for such clinical scenarios. The study group consisted of two male patients with a history of seizure disorder involving loss of consciousness. Clinical data and results of electrocardiography, echocardiography, electroencephalography, and continuous, mobile, outpatient cardiac rhythm monitoring are described. In the first patient, while cardiac bradyarrhythmias were secondary to seizures, sinus arrest most likely complicated the episodes by leading to more prolonged states of unconsciousness. In the second patient, permanent pacemaker implantation for AV block averted all clinical events previously attributed to seizures. Despite the different causal relationships between seizures and bradyarrhythmias in these two patients, mobile, cardiac outpatient telemetry was successful in diagnosing the contribution of cardiac dysrhythmia, leading to permanent pacemaker implantation. A diagnostic strategy that incorporates mobile, noninvasive, continuous, outpatient cardiac rhythm monitoring can effectively be utilized to diagnose significant seizure-related arrhythmias. PMID:19572879

  5. [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

  6. 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

  7. Complex patterns of abnormal heartbeats

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    Individuals having frequent abnormal heartbeats interspersed with normal heartbeats may be at an increased risk of sudden cardiac death. However, mechanistic understanding of such cardiac arrhythmias is limited. We present a visual and qualitative method to display statistical properties of abnormal heartbeats. We introduce dynamical "heartprints" which reveal characteristic patterns in long clinical records encompassing approximately 10(5) heartbeats and may provide information about underlying mechanisms. We test if these dynamics can be reproduced by model simulations in which abnormal heartbeats are generated (i) randomly, (ii) at a fixed time interval following a preceding normal heartbeat, or (iii) by an independent oscillator that may or may not interact with the normal heartbeat. We compare the results of these three models and test their limitations to comprehensively simulate the statistical features of selected clinical records. This work introduces methods that can be used to test mathematical models of arrhythmogenesis and to develop a new understanding of underlying electrophysiologic mechanisms of cardiac arrhythmia.

  8. 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

  9. 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

  10. 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

  11. Level of urinary liver-type fatty acid-binding protein is associated with cardiac markers and electrocardiographic abnormalities in type-2 diabetes with chronic kidney disease stage G1 and G2.

    PubMed

    Maeda, Yoshiteru; Suzuki, Atsushi; Ishii, Junnichi; Sekiguchi-Ueda, Sahoko; Shibata, Megumi; Yoshino, Yasumasa; Asano, Shogo; Hayakawa, Nobuki; Nakamura, Kazuhiro; Akiyama, Yasukazu; Kitagawa, Fumihiko; Sakuishi, Toshiaki; Fujita, Takashi; Hashimoto, Shuji; Ozaki, Yukio; Itoh, Mitsuyasu

    2015-05-01

    Urinary liver-type fatty acid-binding protein (L-FABP) reflects the degree of stress in proximal tubules of the kidney. We examined the level of L-FABP in type-2 diabetes mellitus (T2DM) patients with chronic kidney disease (CKD) stage G1 and G2, and its relationship with cardiac markers and electrocardiographic (ECG) abnormalities. T2DM patients whose estimated glomerular filtration rate (eGFR) was ≥60 mL/min/1.73 m(2) were recruited [n = 276 (165 males), mean age 64 years]. The median level of urinary L-FABP was 6.6 μg/gCr. Urinary L-FABP showed significant correlation with urinary albumin-to-creatinine ratio (ACR) (r = 0.51, p < 0.0001). Median (25th-75th percentile) eGFR was 82 (72-95) mL/min/1.73 m2. We divided patients into four subgroups (group 1, L-FABP ≤8.4 μg/gCr and ACR ≤30 mg/gCr; group 2, L-FABP ≤8.4 μg/gCr and ACR >30 mg/gCr; group 3, L-FABP >8.4 μg/gCr and ACR ≤30 mg/gCr; group 4, L-FABP >8.4 μg/gCr and ACR >30 mg/gCr). Compared with group 1, group 4 was significantly higher in systolic blood pressure, and eGFR using standardized serum cystatin C, high-sensitivity troponin T, and N-terminal pro-brain natriuretic peptide (NT-proBNP). Group 4 had significantly higher level of NT-proBNP than group 3. Groups 2, 3 and 4 showed more ECG abnormalities than group 1. These findings suggest that simultaneous measurement of urinary L-FABP and ACR should be useful to assess cardiovascular damage reflecting on the elevation of cardiac markers and ECG abnormalities in T2DM with CKD G1 and G2. PMID:24626813

  12. Cardiac Innervation and Sudden Cardiac Death

    PubMed Central

    Fukuda, Keiichi; Kanazawa, Hideaki; Aizawa, Yoshiyasu; Ardell, Jeffrey L.; Shivkumar, Kalyanam

    2015-01-01

    Afferent and efferent cardiac neurotransmission via the cardiac nerves intricately modulates nearly all physiological functions of the heart (chronotropy, dromotropy, lusitropy and inotropy). Afferent information from the heart is transmitted to higher levels of the nervous system for processing (intrinsic cardiac nervous system, extracardiac-intrathoracic ganglia, spinal cord, brain stem and higher centers) which ultimately results in efferent cardiomotor neural impulses (via the sympathetic and parasympathetic nerves). This system forms interacting feedback loops that provide physiological stability for maintaining normal rhythm and life-sustaining circulation. This system also ensures that there is fine-tuned regulation of sympathetic-parasympathetic balance in the heart under normal and stressed states in the short (beat to beat), intermediate (minutes-hours) and long term (days-years). This important neurovisceral /autonomic nervous system also plays a major role in the pathophysiology and progression of heart disease, including heart failure and arrhythmias leading to sudden cardiac death (SCD). Transdifferentiation of neurons in heart failure, functional denervation, cardiac and extra-cardiac neural remodeling have also been identified and characterized during the progression of disease. Recent advances in understanding the cellular and molecular processes governing innervation and the functional control of the myocardium in health and disease provides a rational mechanistic basis for development of neuraxial therapies for preventing SCD and other arrhythmias. Advances in cellular, molecular, and bioengineering realms have underscored the emergence of this area as an important avenue of scientific inquiry and therapeutic intervention. PMID:26044253

  13. Chaotic dynamics in cardiac aggregates induced by potassium channel block

    NASA Astrophysics Data System (ADS)

    Quail, Thomas; McVicar, Nevin; Aguilar, Martin; Kim, Min-Young; Hodge, Alex; Glass, Leon; Shrier, Alvin

    2012-09-01

    Chaotic rhythms in deterministic models can arise as a consequence of changes in model parameters. We carried out experimental studies in which we induced a variety of complex rhythms in aggregates of embryonic chick cardiac cells using E-4031 (1.0-2.5 μM), a drug that blocks the hERG potassium channel. Following the addition of the drug, the regular rhythm evolved to display a spectrum of complex dynamics: irregular rhythms, bursting oscillations, doublets, and accelerated rhythms. The interbeat intervals of the irregular rhythms can be described by one-dimensional return maps consistent with chaotic dynamics. A Hodgkin-Huxley-style cardiac ionic model captured the different types of complex dynamics following blockage of the hERG mediated potassium current.

  14. The effect of seeing the rhythm display on performance of cardiopulmonary resuscitation.

    PubMed

    Silfvast, T; Paakkonen, H; Gorski, J

    2002-10-01

    Semiautomated external defibrillators are widely used by prehospital emergency personnel. Some of the devices have a rhythm display and some show only text commands on the screen. To evaluate the effects on cardiopulmonary resuscitation (CPR) performance of seeing the rhythm during resuscitation, 60 fire-fighter students were randomly divided in two groups and trained to use either a defibrillator with a rhythm display or one without a display. The students in both groups formed teams of two rescuers, and their performance of CPR on a manikin was tested using a predefined rhythm sequence in a simulated cardiac arrest situation. The teams using a defibrillator with a rhythm display more often interrupted CPR for pulse checks than those who did not see the rhythm (P=0.003). The duration of CPR between rhythm analyses was shorter in the group who saw the rhythm on the screen (P=0.002). Our data suggest that seeing an organised rhythm on a monitor during CPR interferes with adherence to CPR algorithms which may have a negative influence on the performance of CPR. PMID:12297350

  15. Ultrasound diagnosis of structural abnormalities in the first trimester.

    PubMed

    Dugoff, Lorraine

    2002-04-01

    The advances in ultrasound technology have made it possible to identify fetal structural abnormalities and genetic syndromes in the first trimester. First trimester prenatal diagnosis of fetal central nervous system, renal, gastrointestinal, cardiac, and skeletal abnormalities is reviewed. PMID:11981912

  16. 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

  17. 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

  18. 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.

  19. 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 ...

  20. Nonlinear dynamics, chaos and complex cardiac arrhythmias

    NASA Technical Reports Server (NTRS)

    Glass, L.; Courtemanche, M.; Shrier, A.; Goldberger, A. L.

    1987-01-01

    Periodic stimulation of a nonlinear cardiac oscillator in vitro gives rise to complex dynamics that is well described by one-dimensional finite difference equations. As stimulation parameters are varied, a large number of different phase-locked and chaotic rhythms is observed. Similar rhythms can be observed in the intact human heart when there is interaction between two pacemaker sites. Simplified models are analyzed, which show some correspondence to clinical observations.

  1. 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 ...

  2. 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, ...

  3. 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

  4. 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

  5. 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 ...

  6. 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 ...

  7. 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 ...

  8. 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 ...

  9. 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 ...

  10. 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

  11. Cardiac Rehabilitation

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Cardiac Rehabilitation? Cardiac rehabilitation (rehab) is a medically supervised program ... be designed to meet your needs. The Cardiac Rehabilitation Team Cardiac rehab involves a long-term commitment ...

  12. 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

  13. Prevalence of left atrial abnormalities in atrial fibrillation versus normal sinus patients

    PubMed Central

    Ketai, Loren H; Teague, Shawn D; Rissing, Stacy M

    2016-01-01

    Background Atrial fibrillation (AF) may be the cause or sequela of left atrial abnormalities and variants. Purpose To determine the prevalence of left atrial (LA) abnormalities in AF patients compared to normal sinus rhythm (NSR) patients. Material and Methods We retrospectively reviewed 281 cardiac CT examinations from 2010 to 2012, excluding patients with prior pulmonary vein ablation, known coronary artery disease, prior coronary stent placement, or coronary artery bypass grafts. The first group consisted of 159 AF patients undergoing cardiac CT prior to pulmonary vein ablation and the second group consisted of 122 NSR patients evaluated with coronary CT angiography. Demographic data were collected. LA abnormalities were analyzed. Left atrial diameter was measured on an axial view. Results A total of 281 patients were included. The male gender has significantly higher prevalence of AF than female gender, P value <0.001. Patients with AF were significantly older (mean age, 57.4 years; standard deviation [SD], 11.8 years) than NSR patients (mean age, 53.4 years; SD, 13.6 years), P value, 0.01. The left atrial diameter was greater in the AF patients (mean diameter, 4.3 cm; SD, 0.82 cm) versus the NSR patients (3.4 cm; SD, 0.58 cm), P value, <0.0001. LA diverticulum was the most prevalent variant, occurring in 28.4% of the entire patient population followed by LA pouch, occurring in 24%. There was no significant between group differences in the prevalence of these or the remainder of the LA variants. Conclusion AF patients differed significantly from NSR patients in LA size, gender, and mean age. There was no statistical significance between the two groups with regard to the LA morphologic abnormalities other than size. PMID:27358747

  14. 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 ...

  15. 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

  16. 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.

  17. 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.

  18. Atrial fibrillation management: evaluating rate vs rhythm control.

    PubMed

    Nguyen, Tuan; Jolly, Umjeet; Sidhu, Kiran; Yee, Raymond; Leong-Sit, Peter

    2016-06-01

    Atrial fibrillation (AF) is an increasing global issue leading to increased hospitalizations, adverse health related events and mortality. This review focuses on the management of atrial fibrillation, in particular in the past decade, comparing two major strategies, rate or rhythm control. We evaluate the evidence for each strategy, pharmacological options and the increasing utilization of invasive techniques, in particular catheter ablation and use of implantable cardiac pacing devices. Pharmacological comparative trials evaluating both strategies have shown rate control being non-inferior to rhythm control for clinical outcomes of mortality and other cardiovascular events (including stroke). Catheter ablation techniques, involving radiofrequency ablation and recently cryoablation, have shown promising results in particular with paroxysmal AF. However, persistent AF provides ongoing challenges and will be a particular focus of continued research. PMID:26960034

  19. 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

  20. 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

  1. 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

  2. Cardiac oxidative stress and electrophysiological changes in rats exposed to concentrated ambient particles are mediated by TRP-dependent pulmonary reflexes.

    PubMed

    Ghelfi, Elisa; Rhoden, Claudia Ramos; Wellenius, Gregory A; Lawrence, Joy; Gonzalez-Flecha, Beatriz

    2008-04-01

    Previous studies suggest that, through the stimulation of pulmonary nervous endings, ambient particles modulate the autonomic tone on the heart leading to cardiac oxidant stress and dysfunction. In this paper we investigated the effect of blockade of vanilloid receptor 1 (Transient Receptor Potential Vanilloid Receptor 1 [TRPV1]) on concentrated ambient particles (CAPs)-induced cardiac oxidative stress and dysfunction in a rat model of inhalation exposure. Capsazepine (CPZ), a selective antagonist of TRPV1, was given ip or as an aerosol immediately before exposure to CAPs. Control and CPZ-treated rats were exposed to filtered air or CAPs aerosols for 5 h using the Harvard Ambient Particle Concentrator (mean PM(2.5) mass concentration: 218 +/- 23 mug/m(3)). At the end of the exposure we measured cardiac oxidative stress (in situ chemiluminescence [CL]), lipid peroxidation (thiobarbituric acid reactive substances [TBARS]), and tissue edema. Cardiac function was monitored throughout the exposure. CPZ (ip or aerosol) decreased CAPs-induced CL, lipid TBARS, and edema in the heart, indicating that blocking TRP receptors, systemically or locally, decreases heart CL. CAPs exposure led to significant decreases in heart rate (CAPs 350 +/- 32 bpm, control: 370 +/- 29), and in the length of the QT, RT, Pdur and Tpe intervals. These changes were observable immediately upon exposure and were maintained throughout the 5 h of CAPs inhalation. Changes in cardiac rhythm and electrocardiogram morphology were prevented by CPZ. These data suggest that current abnormalities in CAPs-exposed rats alter the action potentials leading to changes in conduction velocity and ventricular repolarization, and that triggering of TRPV1-mediated autonomic reflexes in the lung is essential for the observed changes in cardiac rhythms. PMID:18184637

  3. Cardiac Catheterization

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Cardiac Catheterization? Cardiac catheterization (KATH-eh-ter-ih-ZA-shun) is a ... disease. Doctors also can use ultrasound during cardiac catheterization to see blockages in the coronary arteries. Ultrasound ...

  4. 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

  5. Introduction: Mapping and control of complex cardiac arrhythmias.

    PubMed

    Christini, David J.; Glass, Leon

    2002-09-01

    This paper serves as an introduction to the Focus Issue on mapping and control of complex cardiac arrhythmias. We first introduce basic concepts of cardiac electrophysiology and describe the main clinical methods being used to treat arrhythmia. We then provide a brief summary of the main themes contained in the articles in this Focus Issue. In recent years there have been important advances in the ability to map the spread of excitation in intact hearts and in laboratory settings. This work has been combined with simulations that use increasingly realistic geometry and physiology. Waves of excitation and contraction in the heart do not always propagate with constant velocity but are often subject to instabilities that may lead to fluctuations in velocity and cycle time. Such instabilities are often treated best in the context of simple one- or two-dimensional geometries. An understanding of the mechanisms of propagation and wave stability is leading to the implementation of different stimulation protocols in an effort to modify or eliminate abnormal rhythms. (c) 2002 American Institute of Physics. PMID:12779601

  6. 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

  7. 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.

  8. Cardiac Delayed Rectifier Potassium Channels in Health and Disease.

    PubMed

    Chen, Lei; Sampson, Kevin J; Kass, Robert S

    2016-06-01

    Cardiac delayed rectifier potassium channels conduct outward potassium currents during the plateau phase of action potentials and play pivotal roles in cardiac repolarization. These include IKs, IKr and the atrial specific IKur channels. In this article, we will review their molecular identities and biophysical properties. Mutations in the genes encoding delayed rectifiers lead to loss- or gain-of-function phenotypes, disrupt normal cardiac repolarization and result in various cardiac rhythm disorders, including congenital Long QT Syndrome, Short QT Syndrome and familial atrial fibrillation. We will also discuss the prospect of using delayed rectifier channels as therapeutic targets to manage cardiac arrhythmia. PMID:27261823

  9. Echocardiographic abnormalities in the mucopolysaccharide storage diseases.

    PubMed

    Gross, D M; Williams, J C; Caprioli, C; Dominguez, B; Howell, R R

    1988-01-01

    The mucopolysaccharide storage diseases express themselves clinically with a wide variety of abnormalities, including growth and mental retardation, skeletal abnormalities, clouded corneas, nerve compression syndromes, upper airway obstruction and cardiovascular involvement, to name the most common. In most cases the cause of early death is cardiorespiratory failure secondary to cardiovascular involvement and upper airway obstruction. The findings of cardiac ultrasound examination in 29 children, adolescents and young adults are presented. In addition to the previously well-described abnormalities of the mitral and aortic valves in several types of mucopolysaccharide storage disease, we report patchy involvement in some cases, 3 instances of asymmetric septal hypertrophy not previously reported in mucopolysaccharide storage diseases, cardiac involvement in half of our patients with Sanfilippo syndrome and a lack of age-related severity of cardiac involvement even within the specific syndromes. PMID:3122547

  10. Hardware-in-the-loop simulation and energy optimization of cardiac pacemakers.

    PubMed

    Barker, Chris; Kwiatkowska, Marta; Mereacre, Alexandru; Paoletti, Nicola; Patane, Andrea

    2015-08-01

    Implantable cardiac pacemakers are medical devices that can monitor and correct abnormal heart rhythms. To provide the necessary safety assurance for pacemaker software, both testing and verification of the code, as well as testing the entire pacemaker hardware in the loop, is necessary. In this paper, we present a hardware testbed that enables detailed hardware-in-the-loop simulation and energy optimisation of pacemaker algorithms with respect to a heart model. Both the heart and the pacemaker models are encoded in Simulink/Stateflow™ and translated into executable code, with the pacemaker executed directly on the microcontroller. We evaluate the usefulness of the testbed by developing a parameter synthesis algorithm which optimises the timing parameters based on power measurements acquired in real-time. The experiments performed on real measurements successfully demonstrate that the testbed is capable of energy minimisation in real-time and obtains safe pacemaker timing parameters. PMID:26737950

  11. 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

  12. Space Derived Health Aids (Cardiac Pacemaker)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    St. Jude Medical's Cardiac Rhythm Management Division's (formerly known as Pacesetter Systems, Inc.) pacer is a rechargeable cardiac pacemaker that eliminates the recurring need for surgery to implant a new battery. The Programalith is an advanced cardiac pacing system which permits a physician to reprogram a patient's implanted pacemaker without surgery. System consists of a pacemaker, together with a physician's console containing the programmer and a data printer. Signals are transmitted by wireless telemetry. Two-way communications, originating from spacecraft electrical power systems technology, allows physician to interrogate the pacemaker as to the status of the heart, then to fine tune the device to best suit the patient's needs.

  13. 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)

  14. 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.

  15. 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…

  16. An overview of cardiac morphogenesis.

    PubMed

    Schleich, Jean-Marc; Abdulla, Tariq; Summers, Ron; Houyel, Lucile

    2013-11-01

    Accurate knowledge of normal cardiac development is essential for properly understanding the morphogenesis of congenital cardiac malformations that represent the most common congenital anomaly in newborns. The heart is the first organ to function during embryonic development and is fully formed at 8 weeks of gestation. Recent studies stemming from molecular genetics have allowed specification of the role of cellular precursors in the field of heart development. In this article we review the different steps of heart development, focusing on the processes of alignment and septation. We also show, as often as possible, the links between abnormalities of cardiac development and the main congenital heart defects. The development of animal models has permitted the unraveling of many mechanisms that potentially lead to cardiac malformations. A next step towards a better knowledge of cardiac development could be multiscale cardiac modelling. PMID:24138816

  17. 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

  18. 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)

  19. 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…

  20. 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…

  1. 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

  2. Rhythm analysis during cardiopulmonary resuscitation: past, present, and future.

    PubMed

    Ruiz de Gauna, Sofia; Irusta, Unai; Ruiz, Jesus; Ayala, Unai; Aramendi, Elisabete; Eftestøl, Trygve

    2014-01-01

    Survival from out-of-hospital cardiac arrest depends largely on two factors: early cardiopulmonary resuscitation (CPR) and early defibrillation. CPR must be interrupted for a reliable automated rhythm analysis because chest compressions induce artifacts in the ECG. Unfortunately, interrupting CPR adversely affects survival. In the last twenty years, research has been focused on designing methods for analysis of ECG during chest compressions. Most approaches are based either on adaptive filters to remove the CPR artifact or on robust algorithms which directly diagnose the corrupted ECG. In general, all the methods report low specificity values when tested on short ECG segments, but how to evaluate the real impact on CPR delivery of continuous rhythm analysis during CPR is still unknown. Recently, researchers have proposed a new methodology to measure this impact. Moreover, new strategies for fast rhythm analysis during ventilation pauses or high-specificity algorithms have been reported. Our objective is to present a thorough review of the field as the starting point for these late developments and to underline the open questions and future lines of research to be explored in the following years. PMID:24527445

  3. A Short History of Cardiac Inspection: A Quest "To See with a Better Eye".

    PubMed

    Evans, William N

    2015-08-01

    Cardiac examination has evolved over centuries. The goal of cardiac evaluation, regardless the era, is to "see" inside the heart to diagnose congenital and acquired intra-cardiac structural and functional abnormalities. This article briefly reviews the history of cardiac examination and discusses contemporary best, evidence-based methods of cardiac inspection. PMID:25835202

  4. Effect of mediastinal irradiation on cardiac function of patients treated during childhood and adolescence for Hodgkin's disease

    SciTech Connect

    Green, D.M.; Gingell, R.L.; Pearce, J.; Panahon, A.M.; Ghoorah, J.

    1987-02-01

    To determine the frequency of cardiac dysfunction in patients treated during childhood or adolescence with mediastinal irradiation for Hodgkin's disease (HD), 28 patients underwent cardiac evaluation 19 to 182 months (median, 90 months) after the completion of radiation therapy. No patient had symptoms of cardiac disease. All were normotensive. All patients had a normal cardiothoracic ratio. There were no abnormalities of voltage or rhythm in the ECGs. The left ventricular end diastolic volume was increased in 19.2% of patients, none of whom had evidence of impaired left ventricular function. The left ventricular ejection fraction (LVEF) was increased in 15.3% of patients. No patient had a decreased LVEF. Pericardial thickening was demonstrated on echocardiograms from 12 of 28 patients (42.9%). Thickening was more frequent among those patients observed for 72 or more months (47.1%; eight of 17) than among those with shorter periods of follow-up (36.4%; four of 11). This study demonstrates that cardiac dysfunction is an infrequent sequela of mediastinal irradiation following treatment using an equally weighted, anterior-posterior technique. Longitudinal study of these patients will be necessary to determine the clinical significance and evolution of the occult pericardial thickening that was identified.

  5. The EINTHOVEN system: toward an improved cardiac arrhythmia monitor.

    PubMed Central

    Widman, L. E.

    1991-01-01

    Contemporary cardiac arrhythmia monitors, used commonly in intensive care settings, are highly sensitive to artifact, resulting in high false alarm rates, inability to detect P waves reliably, and crude rhythm interpretation. We report on two new approaches that address these problems: a noise preprocessor that characterizes the type and degree of artifact in an ECG, and a model-based rhythm interpretation algorithm. PMID:1807639

  6. Cell and gene therapy for arrhythmias: Repair of cardiac conduction damage

    PubMed Central

    Xiao, Yong-Fu

    2011-01-01

    Action potentials generated in the sinoatrial node (SAN) dominate the rhythm and rate of a healthy human heart. Subsequently, these action potentials propagate to the whole heart via its conduction system. Abnormalities of impulse generation and/or propagation in a heart can cause arrhythmias. For example, SAN dysfunction or conduction block of the atrioventricular node can lead to serious bradycardia which is currently treated with an implanted electronic pacemaker. On the other hand, conduction damage may cause reentrant tachyarrhythmias which are primarily treated pharmacologically or by medical device-based therapies, including defibrillation and tissue ablation. However, drug therapies sometimes may not be effective or are associated with serious side effects. Device-based therapies for cardiac arrhythmias, even with well developed technology, still face inadequacies, limitations, hardware complications, and other challenges. Therefore, scientists are actively seeking other alternatives for antiarrhythmic therapy. In particular, cells and genes used for repairing cardiac conduction damage/defect have been investigated in various studies both in vitro and in vivo. Despite the complexities of the excitation and conduction systems of the heart, cell and gene-based strategies provide novel alternatives for treatment or cure of cardiac arrhythmias. This review summarizes some highlights of recent research progress in this field. PMID:22783301

  7. Robust cardiac event change detection method for long-term healthcare monitoring applications.

    PubMed

    Satija, Udit; Ramkumar, Barathram; Manikandan, M Sabarimalai

    2016-06-01

    A long-term continuous cardiac health monitoring system highly demands more battery power for real-time transmission of electrocardiogram (ECG) signals and increases bandwidth, treatment costs and traffic load of the diagnostic server. In this Letter, the authors present an automated low-complexity robust cardiac event change detection (CECD) method that can continuously detect specific changes in PQRST morphological patterns and heart rhythms and then enable transmission/storing of the recorded ECG signals. The proposed CECD method consists of four stages: ECG signal quality assessment, R-peak detection and beat waveform extraction, temporal and RR interval feature extraction and cardiac event change decision. The proposed method is tested and validated using both normal and abnormal ECG signals including different types of arrhythmia beats, heart rates and signal quality. Results show that the method achieves an average sensitivity of 99.76%, positive predictivity of 94.58% and overall accuracy of 94.32% in determining the changes in heartbeat waveforms of the ECG signals. PMID:27382480

  8. Evaluation of cardiac rhythm disturbances during extravehicular activity

    NASA Technical Reports Server (NTRS)

    Rossum, A. C.; Wood, M. L.; Bishop, S. L.; Deblock, H.; Charles, J. B.

    1997-01-01

    This study represents the first systematic evaluation of dysrhythmias before, during, and after spaceflight including extravehicular activity (EVA). The data, based on 7 Shuttle crew members, revealed a nonsignificant decrease in ventricular and supraventricular ectopy during EVA, suggesting that the incidence of dysrhythmias is no greater during EVA than with any other phase of a mission or preflight.

  9. Blue sky catastrophe as applied to modeling of cardiac rhythms

    NASA Astrophysics Data System (ADS)

    Glyzin, S. D.; Kolesov, A. Yu.; Rozov, N. Kh.

    2015-07-01

    A new mathematical model for the electrical activity of the heart is proposed. The model represents a special singularly perturbed three-dimensional system of ordinary differential equations with one fast and two slow variables. A characteristic feature of the system is that its solution performs nonclassical relaxation oscillations and simultaneously undergoes a blue sky catastrophe bifurcation. Both these factors make it possible to achieve a phenomenological proximity between the time dependence of the fast component in the model and an ECG of the human heart.

  10. Sleep and cardiac rhythm in the gray seal.

    PubMed

    Ridgway, S H; Harrison, R J; Joyce, P L

    1975-02-14

    Telemetric studies of electroencephalograms, electrocardiograms, and electroculograms and concurrent observations of behavior revealed that seals can sleep underwater, on the surface, or while hauled out. Rapid eye movement preceded slow wave sleep and was accompanied by increased respiratory rate and rhythmic tachycardia. While slow wave sleep occurred under all sleep conditions, rapid eye movement occurred only when a seal was hanging at the water surface or hauled out, never underwater. PMID:163484

  11. Circadian variation in witnessed out of hospital cardiac arrest

    PubMed Central

    Soo, L; Gray, D; Young, T; Hampton, J

    2000-01-01

    OBJECTIVES—To examine the effect on circadian variation of out of hospital cardiac arrest according to the underlying aetiology and presenting rhythm of arrest, and to explore strategies that might help to improve survival outcome using circadian variation.
DESIGN—Population based retrospective study.
SETTING—County of Nottinghamshire with a total population of 993 914 and an area of 2183 km2.
SUBJECTS—Between 1 January 1991 and 3 December 1994, all witnessed cardiac arrests attended by the Nottinghamshire Ambulance Service, of which 1196 patients had a cardiac cause for their arrest (ICD, 9th revision, codes 390-414 and 420-429) and 339 had a non-cardiac cause.
RESULTS—The circadian variation of the cardiac cases was not significantly different from that of non-cardiac cases (p = 0.587), even when adjusted for age, sex, or presenting rhythm of arrest. For cardiac cases, the circadian variation of those who presented with ventricular fibrillation was significantly different from those presenting with a rhythm other than ventricular fibrillation (p = 0.005), but was similar to the circadian variation of bystander cardiopulmonary resuscitation (p = 0.306) and survivors (p = 0.542). Ambulance response time was also found to have a circadian variation.
CONCLUSIONS—There is a common circadian variation of out of hospital cardiac arrest, irrespective of underlying aetiology, where the presenting rhythm is other than ventricular fibrillation. This is different from the circadian variation of cases of cardiac aetiology presenting with ventricular fibrillation. The circadian variation of ventricular fibrillation, and consequently survival, may be affected by the availability of bystander cardiopulmonary resuscitation and the speed of ambulance response.


Keywords: out of hospital; cardiac arrest; circadian variation PMID:10995402

  12. 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

  13. 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.

  14. [Cardiac sarcoidosis - clinical manifestation and diagnosis].

    PubMed

    Błaut-Jurkowska, Justyna; Podolec, Piotr; Olszowska, Maria

    2016-08-01

    Sarcoidosis is a multisystem inflammatory disease defined histologically by the formation of noncaseating granulomas. The etiology of sarcoidosis remains unknown. Heart involvement in the course of sarcoidosis concerns about 5% of patients. The most common manifestation of cardiac sarcoidosis are conduction abnormalities, arrhythmias and heart failure. The diagnostic algorithm includes performing a clinical history, a 12-lead electrocardiogram (ECG) and an echocardiogram. If any of the initial screening investigations yields an abnormality, diagnostics should be continue using advanced imaging techniques: cardiovascular magnetic resonance (CMR) or fluorodeoxyglucose positron emission tomography (FDG-PET). Nowadays endomyocardial biopsy is not performed routinely.The clinical picture of cardiac sarcoidosis is highly variable. Screening for cardiac sarcoidosis should be performed in all patients diagnosed with extracardiac sarcoidosis. Cardiac sarcoidosis should also be suspected in young patients without a diagnosis of sarcoidosis who present with conduction abnormalities of unknown etiology, because cardiac sarcoidosis may be the first or the only manifestation of the disease. PMID:27591449

  15. [Cardiac sarcoidosis - clinical manifestation and diagnosis].

    PubMed

    Błaut-Jurkowska, Justyna; Podolec, Piotr; Olszowska, Maria

    2016-07-01

    Sarcoidosis is a multisystem inflammatory disease defined histologically by the formation of noncaseating granulomas. The etiology of sarcoidosis remains unknown. Heart involvement in the course of sarcoidosis concerns about 5% of patients. The most common manifestation of cardiac sarcoidosis are conduction abnormalities, arrhythmias and heart failure. The diagnostic algorithm includes performing a clinical history, a 12-lead electrocardiogram (ECG) and an echocardiogram. If any of the initial screening investigations yields an abnormality, diagnostics should be continue using advanced imaging techniques: cardiovascular magnetic resonance (CMR) or fluorodeoxyglucose positron emission tomography (FDG-PET). Nowadays endomyocardial biopsy is not performed routinely.The clinical picture of cardiac sarcoidosis is highly variable. Screening for cardiac sarcoidosis should be performed in all patients diagnosed with extracardiac sarcoidosis. Cardiac sarcoidosis should also be suspected in young patients without a diagnosis of sarcoidosis who present with conduction abnormalities of unknown etiology, because cardiac sarcoidosis may be the first or the only manifestation of the disease. PMID:27590654

  16. Carney complex with biatrial cardiac myxoma.

    PubMed

    Havrankova, Eniko; Stenova, Emoke; Olejarova, Ingrid; Sollarova, Katarina; Kinova, Sona

    2014-01-01

    Cardiac myxomas make up approximately 50% of all benign cardiac tumors and represented 86% of all surgically treated cardiac tumors. Most of them originated from the left atrium, in some cases from both of atria. We report a case of male patient with biatrial myxomas and other extra-cardiac involvement: hypophyseal adenoma, enlargement of thyroid gland, tubular adenoma polyp of colon and bilateral large cell calcifying Sertoli cell tumor (LCCSCT) of testis. These findings led to the diagnosis of Carney's complex, which is a syndrome with multiple neoplasias, cardiac myxomas, lentigines, and endocrine abnormalities. A genetic test confirm this diagnosis. PMID:24088910

  17. Cardiac Imaging In Athletes

    PubMed Central

    Khan, Asaad A.; Safi, Lucy; Wood, Malissa

    2016-01-01

    Athletic heart syndrome refers to the physiological and morphological changes that occur in a human heart after repetitive strenuous physical exercise. Examples of exercise-induced changes in the heart include increases in heart cavity dimensions, augmentation of cardiac output, and increases in heart muscle mass. These cardiac adaptations vary based on the type of exercise performed and are often referred to as sport-specific cardiac remodeling. The hemodynamic effects of endurance and strength training exercise lead to these adaptations. Any abnormalities in chamber dilatation and left ventricular function usually normalize with cessation of exercise. Athletic heart syndrome is rare and should be differentiated from pathologic conditions such as hypertrophic cardiomyopathy, left ventricular noncompaction, and arrhythmogenic right ventricular dysplasia when assessing a patient for athletic heart syndrome. This paper describes specific adaptations that occur in athletic heart syndrome and tools to distinguish between healthy alterations versus underlying pathology. PMID:27486490

  18. 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

  19. 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

  20. Mapping of cardiac electrophysiology onto a dynamic patient-specific heart model.

    PubMed

    Wilson, Kevin; Guiraudon, Gerard; Jones, Douglas L; Peters, Terry M

    2009-12-01

    Electrophysiological cardiac data mapping is an essential tool for the study of cardiac rhythm disorders, such as atrial fibrillation. Over the past decade, various advanced cardiac mapping systems have been developed to create detailed cardiac maps and assist physicians in diagnosis and therapy guidance. While these systems have increased the ability to study and treat cardiac arrhythmias, inherent limitations exist. The objective of this paper is to describe and evaluate a system that extends current approaches to cardiac mapping, to create a dynamic cardiac map, using patient-specific cardiac models. This paper details novel approaches to collecting a stream of electrophysiological cardiac data, registering the data with patient-specific dynamic cardiac models, and displaying the data directly on the dynamic model surface, giving a more accurate and comprehensive visualization environment when compared to current systems. To validate the system, a series of laboratory and in vivo experiments were conducted. In the laboratory studies, the system was used to test the user's ability to accurately locate a landmark in physical space, as well as their ability to accurately navigate to a virtual location. In the in vivo studies the overall system performance was compared to an existing electrophysiological recording system, where right atrial cardiac maps were created during sinus and paced cardiac rhythms. The results showed that the new dynamic cardiac mapping system was able to maintain high accuracy in locating physical and virtual landmarks, while being able to create a dynamic cardiac map displayed on a dynamic cardiac surface model. PMID:19423433

  1. 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

  2. Athletes at Risk for Sudden Cardiac Death

    ERIC Educational Resources Information Center

    Subasic, Kim

    2010-01-01

    High school athletes represent the largest group of individuals affected by sudden cardiac death, with an estimated incidence of once or twice per week. Structural cardiovascular abnormalities are the most frequent cause of sudden cardiac death. Athletes participating in basketball, football, track, soccer, baseball, and swimming were found to…

  3. Circadian rhythms in anesthesia and critical care medicine: potential importance of circadian disruptions.

    PubMed

    Brainard, Jason; Gobel, Merit; Bartels, Karsten; Scott, Benjamin; Koeppen, Michael; Eckle, Tobias

    2015-03-01

    The rotation of the earth and associated alternating cycles of light and dark--the basis of our circadian rhythms--are fundamental to human biology and culture. However, it was not until 1971 that researchers first began to describe the molecular mechanisms for the circadian system. During the past few years, groundbreaking research has revealed a multitude of circadian genes affecting a variety of clinical diseases, including diabetes, obesity, sepsis, cardiac ischemia, and sudden cardiac death. Anesthesiologists, in the operating room and intensive care units, manage these diseases on a daily basis as they significantly affect patient outcomes. Intriguingly, sedatives, anesthetics, and the intensive care unit environment have all been shown to disrupt the circadian system in patients. In the current review, we will discuss how newly acquired knowledge of circadian rhythms could lead to changes in clinical practice and new therapeutic concepts. PMID:25294583

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. The influence of motor activity on the development of cardiac arrhythmias during experimental emotional stress

    NASA Technical Reports Server (NTRS)

    Ulyaninskiy, L. S.; Urmancheyeva, T. G.; Stepanyan, Y. P.; Fufacheva, A. A.; Gritsak, A. V.; Kuznetsova, B. A.; Kvitka, A. A.

    1982-01-01

    Experimental emotional stress which can produce various disorders of cardiac rhythm: sinus tachycardia, atrial fibrillation, ventricular, extrasystoles and paroxysmal ventricular tachysystoles was studied. In these conditions the adrenalin content in the blood and myocardium is increased 3 to 4 times. It is found that moderate motor activity leads to a relative decrease of adrenalin in the myocardium and arrest of cardiac arrhythmias.

  11. 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

  12. Dipyridamole cardiac imaging

    SciTech Connect

    Iskandrian, A.S.; Heo, J.; Askenase, A.; Segal, B.L.; Auerbach, N.

    1988-02-01

    Dipyridamole cardiac imaging is a useful alternative technique to exercise stress testing in the evaluation of patients with ischemic heart disease. Intravenous dipyridamole is still in the investigational phase, while oral dipyridamole is widely available. The hemodynamic effects of dipyridamole include an increase in coronary blood flow (due to coronary vasodilation) which is in excess of the increase in myocardial oxygen consumption and cardiac output. The disparity in the increase in coronary blood flow relative to the cardiac output results in an increase in myocardial thallium activity and an increase in the myocardial/background activity ratio. The quality of the thallium images is better or similar to that of exercise thallium images. The optimal dose of intravenous dipyridamole is 0.56 mg/kg, and of the oral dose it is 300 to 400 mg, although higher doses may be necessary in some patients. Analysis of the thallium images has been to a large extent based on visual inspection of the planar images. Delayed images are helpful to establish the nature of the perfusion abnormalities (transient or fixed). The process of redistribution is based on disparate rates of washout from the normal and abnormal zones. The sensitivity and specificity of dipyridamole thallium imaging, whether intravenous or oral, have been shown in a number of studies to be quite adequate and comparable to that achieved during exercise thallium imaging. Dipyridamole two-dimensional echocardiography has also been used in the detection of coronary artery disease; transient (new or worsening of preexisting) wall motion abnormalities have been found to be a specific marker of coronary artery disease. Transmural as well as regional coronary steal phenomena have been postulated as the mechanism for dipyridamole-induced regional wall motion abnormalities. 65 references.

  13. Frequency of Electrocardiographic Abnormalities in Tramadol Poisoned Patients; a Brief Report

    PubMed Central

    Alizadeh Ghamsari, Anahita; Dadpour, Bita; Najari, Fares

    2016-01-01

    Introduction: Previous studies have raised the probably of cardiac manifestation in tramadol poisoning. However, conclusive information on electrocardiographic (ECG) abnormalities of tramadol overdose remains to be explained. Therefore, the present study aimed to evaluate the epidemiology of ECG abnormalities in tramadol poisoned patients. Methods: In a prospective cross-sectional study, all patients with tramadol poisoning, who were admitted to the emergency department of Loghman Hospital during 2012 – 2013, were evaluated. Patients’ baseline characteristics and ECG findings including axis, rate, rhythm, PR interval, QRS duration, QTc interval, evidence of Brugada pattern, and evidence of blocks were recorded. Obtained Data were descriptively analyzed using SPSS 21.0 statistical software. Results: 1402 patients with the mean age of 24 ± 6 years were studied (71.1% male). Sinus tachycardia was detected in 463 (33%) patients, sinus bradycardia in one patient (0.07%), right axis deviation in 340 (24.2), QRS widening in 91 (6.5%), long QTc interval in 259 (18.4%), dominant S wave in either I or aVL lead in 395 (28.1%), and right bundle branch block in 73 (5.2%). Increased PR interval was not detected in any cases. The evidence of Brugada pattern was observed in 2 (0.14%) patients (100% male), both symptomatized with seizure. All abnormalities had same sex distribution. Conclusion: Based on the results of the present study, the most common types of ECG changes were sinus tachycardia, a deep S wave in leads I and aVL, right axis deviation, and long QTc interval, respectively. Brugada pattern and sinus bradycardia were rarely presented. PMID:27299145

  14. 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…

  15. 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…

  16. 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.

  17. Cardiac Na Channels: Structure to Function.

    PubMed

    DeMarco, K R; Clancy, C E

    2016-01-01

    Heart rhythms arise from electrical activity generated by precisely timed opening and closing of ion channels in individual cardiac myocytes. Opening of the primary cardiac voltage-gated sodium (NaV1.5) channel initiates cellular depolarization and the propagation of an electrical action potential that promotes coordinated contraction of the heart. The regularity of these contractile waves is critically important since it drives the primary function of the heart: to act as a pump that delivers blood to the brain and vital organs. When electrical activity goes awry during a cardiac arrhythmia, the pump does not function, the brain does not receive oxygenated blood, and death ensues. Perturbations to NaV1.5 may alter the structure, and hence the function, of the ion channel and are associated downstream with a wide variety of cardiac conduction pathologies, such as arrhythmias. PMID:27586288

  18. 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

  19. Physiological and pathological cardiac hypertrophy.

    PubMed

    Shimizu, Ippei; Minamino, Tohru

    2016-08-01

    The heart must continuously pump blood to supply the body with oxygen and nutrients. To maintain the high energy consumption required by this role, the heart is equipped with multiple complex biological systems that allow adaptation to changes of systemic demand. The processes of growth (hypertrophy), angiogenesis, and metabolic plasticity are critically involved in maintenance of cardiac homeostasis. Cardiac hypertrophy is classified as physiological when it is associated with normal cardiac function or as pathological when associated with cardiac dysfunction. Physiological hypertrophy of the heart occurs in response to normal growth of children or during pregnancy, as well as in athletes. In contrast, pathological hypertrophy is induced by factors such as prolonged and abnormal hemodynamic stress, due to hypertension, myocardial infarction etc. Pathological hypertrophy is associated with fibrosis, capillary rarefaction, increased production of pro-inflammatory cytokines, and cellular dysfunction (impairment of signaling, suppression of autophagy, and abnormal cardiomyocyte/non-cardiomyocyte interactions), as well as undesirable epigenetic changes, with these complex responses leading to maladaptive cardiac remodeling and heart failure. This review describes the key molecules and cellular responses involved in physiological/pathological cardiac hypertrophy. PMID:27262674

  20. 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

  1. 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

  2. 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.

  3. 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

  4. Historical perspectives of cardiac electrophysiology.

    PubMed

    Lüderitz, Berndt

    2009-01-01

    The diagnosis and treatment of clinical electrophysiology has a long and fascinating history. From earliest times, no clinical symptom impressed the patient (and the physician) more than an irregular heart beat. Although ancient Chinese pulse theory laid the foundation for the study of arrhythmias and clinical electrophysiology in the 5th century BC, the most significant breakthrough in the identification and treatment of cardiac arrhythmias first occurred in this century. In the last decades, our knowledge of electrophysiology and pharmacology has increased exponentially. The enormous clinical significance of cardiac rhythm disturbances has favored these advances. On the one hand, patients live longer and thus are more likely to experience arrhythmias. On the other hand, circulatory problems of the cardiac vessels have increased enormously, and this has been identified as the primary cause of cardiac rhythm disorders. Coronary heart disease has become not just the most significant disease of all, based on the statistics for cause of death. Arrhythmias are the main complication of ischemic heart disease, and they have been directly linked to the frequently arrhythmogenic sudden death syndrome, which is now presumed to be an avoidable "electrical accident" of the heart. A retrospective look--often charming in its own right--may not only make it easier to sort through the copious details of this field and so become oriented in this universe of important and less important facts: it may also provide the observer with a chronological vantage point from which to view the subject. The study of clinical electrophysiology is no dry compendium of facts and figures, but rather a dynamic field of study evolving out of the competition between various ideas, intentions and theories. PMID:19196616

  5. Predictive Value of Beat-to-Beat QT Variability Index across the Continuum of Left Ventricular Dysfunction: Competing Risks of Non-cardiac or Cardiovascular Death, and Sudden or Non-Sudden Cardiac Death

    PubMed Central

    Tereshchenko, Larisa G.; Cygankiewicz, Iwona; McNitt, Scott; Vazquez, Rafael; Bayes-Genis, Antoni; Han, Lichy; Sur, Sanjoli; Couderc, Jean-Philippe; Berger, Ronald D.; de Luna, Antoni Bayes; Zareba, Wojciech

    2012-01-01

    Background The goal of this study was to determine the predictive value of beat-to-beat QT variability in heart failure (HF) patients across the continuum of left ventricular dysfunction. Methods and Results Beat-to-beat QT variability index (QTVI), heart rate variance (LogHRV), normalized QT variance (QTVN), and coherence between heart rate variability and QT variability have been measured at rest during sinus rhythm in 533 participants of the Muerte Subita en Insuficiencia Cardiaca (MUSIC) HF study (mean age 63.1±11.7; males 70.6%; LVEF >35% in 254 [48%]) and in 181 healthy participants from the Intercity Digital Electrocardiogram Alliance (IDEAL) database. During a median of 3.7 years of follow-up, 116 patients died, 52 from sudden cardiac death (SCD). In multivariate competing risk analyses, the highest QTVI quartile was associated with cardiovascular death [hazard ratio (HR) 1.67(95%CI 1.14-2.47), P=0.009] and in particular with non-sudden cardiac death [HR 2.91(1.69-5.01), P<0.001]. Elevated QTVI separated 97.5% of healthy individuals from subjects at risk for cardiovascular [HR 1.57(1.04-2.35), P=0.031], and non-sudden cardiac death in multivariate competing risk model [HR 2.58(1.13-3.78), P=0.001]. No interaction between QTVI and LVEF was found. QTVI predicted neither non-cardiac death (P=0.546) nor SCD (P=0.945). Decreased heart rate variability (HRV) rather than increased QT variability was the reason for increased QTVI in this study. Conclusions Increased QTVI due to depressed HRV predicts cardiovascular mortality and non-sudden cardiac death, but neither SCD nor excracardiac mortality in HF across the continuum of left ventricular dysfunction. Abnormally augmented QTVI separates 97.5% of healthy individuals from HF patients at risk. PMID:22730411

  6. 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

  7. 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

  8. Hepato-cardiac disorders

    PubMed Central

    Fouad, Yasser Mahrous; Yehia, Reem

    2014-01-01

    Understanding the mutual relationship between the liver and the heart is important for both hepatologists and cardiologists. Hepato-cardiac diseases can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. Differential diagnoses of liver injury are extremely important in a cardiologist’s clinical practice calling for collaboration between cardiologists and hepatologists due to the many other diseases that can affect the liver and mimic haemodynamic injury. Acute and chronic heart failure may lead to acute ischemic hepatitis or chronic congestive hepatopathy. Treatment in these cases should be directed to the primary heart disease. In patients with advanced liver disease, cirrhotic cardiomyopathy may develop including hemodynamic changes, diastolic and systolic dysfunctions, reduced cardiac performance and electrophysiological abnormalities. Cardiac evaluation is important for patients with liver diseases especially before and after liver transplantation. Liver transplantation may lead to the improvement of all cardiac changes and the reversal of cirrhotic cardiomyopathy. There are systemic diseases that may affect both the liver and the heart concomitantly including congenital, metabolic and inflammatory diseases as well as alcoholism. This review highlights these hepatocardiac diseases PMID:24653793

  9. 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…

  10. 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

  11. Cardiac metastases

    PubMed Central

    Bussani, R; De‐Giorgio, F; Abbate, A; Silvestri, F

    2007-01-01

    Tumours metastatic to the heart (cardiac metastases) are among the least known and highly debated issues in oncology, and few systematic studies are devoted to this topic. Although primary cardiac tumours are extremely uncommon (various postmortem studies report rates between 0.001% and 0.28%), secondary tumours are not, and at least in theory, the heart can be metastasised by any malignant neoplasm able to spread to distant sites. In general, cardiac metastases are considered to be rare; however, when sought for, the incidence seems to be not as low as expected, ranging from 2.3% and 18.3%. Although no malignant tumours are known that diffuse preferentially to the heart, some do involve the heart more often than others—for example, melanoma and mediastinal primary tumours. This paper attempts to review the pathophysiology of cardiac metastatic disease, epidemiology and clinical presentation of cardiac metastases, and pathological characterisation of the lesions. PMID:17098886

  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. 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

  14. 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

  15. Decreased mRNA levels of cardiac Cx43 and ZO1 in sudden cardiac death related to coronary atherosclerosis: a pilot study.

    PubMed

    Xue, Ye; Zhao, Rui; Du, Si-Hao; Zhao, Dong; Li, Dong-Ri; Xu, Jing-Tao; Xie, Xiao-Li; Wang, Qi

    2016-07-01

    Sudden cardiac death (SCD) is the most frequent cause of sudden unexplained death in forensic practice. The most common cause of SCD is coronary artery disease related to coronary atherosclerosis. Previous study suggested the possible application of connexin 43 (Cx43) and zonula occludens-1 (ZO1) immunostaining in the early diagnosis of myocardial ischemia. However, there appears to be insufficient data with regard to their mRNA levels. The present study investigated the cardiac mRNA levels of Cx43 and ZO1, using forensic autopsy materials consisting of 41 control cases without any disease or structural abnormality of the heart (group 1), 32 deaths due to acute ischemic heart disease related to coronary atherosclerosis without apparent myocardial necrosis (group 2), and 29 traumatic deaths with coronary atherosclerosis (group 3). Ten candidate reference genes were evaluated in the left ventricles of 10 forensic autopsy cases. EEF1A1, PPIA, TPT1, and RPL13A were identified as the most stable reference genes. Using these validated reference genes, mRNA levels of Cx43 and ZO1 were examined in the bilateral ventricles and atria of the heart. Relative mRNA quantification demonstrated decreased calibrated normalized relative quantity (CNRQ) values of Cx43 and ZO1 in bilateral ventricles of group 2. When using one conventional reference gene (GAPDH or ACTB) for normalization, nearly no difference was detected among the three groups. These findings indicate that ventricular gap junction remodeling may be a key contributor to rhythm disturbances. Analysis of cardiac Cx43 and ZO1 using real-time PCR is useful in diagnosis of SCD, and validation of reference genes is crucial. PMID:26972693

  16. 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

  17. 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

  18. Cardiac Lymphoma.

    PubMed

    Jeudy, Jean; Burke, Allen P; Frazier, Aletta Ann

    2016-07-01

    Lymphoma of the heart and pericardium may develop in up to 25% of patients with disseminated nodal disease, but primary cardiac lymphoma is rare. The majority are diffuse large B-cell lymphomas, which arise in immunocompetent older individuals, men twice as often as women. Subsets are found in immunocompromised patients, including those with HIV-AIDS or allograft recipients. Cardiac lymphomas tend to arise in the wall of the right heart, especially right atrium, with contiguous infiltration of epicardium and pericardium. Pericardial implants and effusions are common. The disease is often multifocal in the heart, but cardiac valves are usually spared. PMID:27265603

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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 ...

  5. 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 ...

  6. Cardiac arrest

    MedlinePlus

    ... treatment for cardiac arrest. It is a medical device that gives an electrical shock to the heart. The shock can get the heart beating normally again. Small, portable defibrillators are often available in public areas for ...

  7. Cardiac rehabilitation

    MedlinePlus

    ... 123-210. Thomas PD. Exercise-Based, Comprehensive Cardiac Rehabilitation. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 9th ed. Philadelphia, PA: Saunders Elsevier; 2011: ...

  8. Cardiac rehabilitation

    MedlinePlus

    ... goal of cardiac rehab is to: Improve your cardiovascular function Improve your overall health and quality of ... E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, PA: Elsevier Saunders; 2015: ...

  9. Cardiac Sarcoidosis

    MedlinePlus

    ... is Cardiac Sarcoidosis? Sarcoidosis is a poorly understood disease that commonly affects the lungs. It can also involve the lymph nodes, liver, spleen, eyes, skin, bones, salivary glands and heart. ...

  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. Sudden Cardiac Arrest (SCA)

    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 ...

  12. Accurate means of detecting and characterizing abnormal patterns of ventricular activation by phase image analysis

    SciTech Connect

    Botvinick, E.H.; Frais, M.A.; Shosa, D.W.; O'Connell, J.W.; Pacheco-Alvarez, J.A.; Scheinman, M.; Hattner, R.S.; Morady, F.; Faulkner, D.B.

    1982-08-01

    The ability of scintigraphic phase image analysis to characterize patterns of abnormal ventricular activation was investigated. The pattern of phase distribution and sequential phase changes over both right and left ventricular regions of interest were evaluated in 16 patients with normal electrical activation and wall motion and compared with those in 8 patients with an artificial pacemaker and 4 patients with sinus rhythm with the Wolff-Parkinson-White syndrome and delta waves. Normally, the site of earliest phase angle was seen at the base of the interventricular septum, with sequential change affecting the body of the septum and the cardiac apex and then spreading laterally to involve the body of both ventricles. The site of earliest phase angle was located at the apex of the right ventricle in seven patients with a right ventricular endocardial pacemaker and on the lateral left ventricular wall in one patient with a left ventricular epicardial pacemaker. In each case the site corresponded exactly to the position of the pacing electrode as seen on posteroanterior and left lateral chest X-ray films, and sequential phase changes spread from the initial focus to affect both ventricles. In each of the patients with the Wolff-Parkinson-White syndrome, the site of earliest ventricular phase angle was located, and it corresponded exactly to the site of the bypass tract as determined by endocardial mapping. In this way, four bypass pathways, two posterior left paraseptal, one left lateral and one right lateral, were correctly localized scintigraphically. On the basis of the sequence of mechanical contraction, phase image analysis provides an accurate noninvasive method of detecting abnormal foci of ventricular activation.

  13. [On mechanisms of triggering of primary excitation rhythms in vertebrates (phylo- and ontogenic aspects)].

    PubMed

    Belich, A I; Konstantinova, N N; Pavlova, N G

    2009-01-01

    There has been performed the comparative-ontogenetic analysis of literature and our own data obtained at study of regularities of formation of spontaneous stereotypic motor acts at the initial stages of the human fetuses and at early stages of phylogenesis of vertebrates (fisches, amphibians, reptiles) as well as at using natural biological models, such as anencephaly of human fetus, the human artificially produced therapeutic electroconvulsive fit, and winter hibernation in mammals. This analysis has allowed showing that the prenervous and non-nervous motorics and cardiac rhythm revealed in the series of vertebrates including human fetus represent a universal phenomenon that is due to the role of prenervous transmitters as local hormones participating in triggering and regulation of this motoric - the primary rhythms of excitation in vertebrate phylo- and ontogenesis. PMID:20063784

  14. In-Hospital Cardiac Arrest: An Update on Pulseless Electrical Activity and Asystole.

    PubMed

    Attin, Mina; Tucker, Rebecca G; Carey, Mary G

    2016-09-01

    Nonshockable rhythms, including pulseless electrical activity (PEA) and asystole, precede more than 70% of in-hospital cardiac arrests (I-HCA). Compared with shockable rhythms (ventricular fibrillation and ventricular tachycardia), nonshockable rhythms have higher mortality and morbidity. Therefore, investigating the underlying mechanisms of these arrhythmias to improve the quality of care and outcome for patients who suffer cardiac arrest is a priority. As the first responders to I-HCA, nurses must have the proper knowledge and training to provide timely and efficient cardiopulmonary resuscitation therapy. This article provides an overview of nonshockable cardiac arrhythmias preceding I-HCA as a means of addressing the gap between science and clinical practice. PMID:27484665

  15. Drosophila Models of Cardiac Disease

    PubMed Central

    Piazza, Nicole; Wessells, R.J.

    2013-01-01

    The fruit fly Drosophila melanogaster has emerged as a useful model for cardiac diseases, both developmental abnormalities and adult functional impairment. Using the tools of both classical and molecular genetics, the study of the developing fly heart has been instrumental in identifying the major signaling events of cardiac field formation, cardiomyocyte specification, and the formation of the functioning heart tube. The larval stage of fly cardiac development has become an important model system for testing isolated preparations of living hearts for the effects of biological and pharmacological compounds on cardiac activity. Meanwhile, the recent development of effective techniques to study adult cardiac performance in the fly has opened new uses for the Drosophila model system. The fly system is now being used to study long-term alterations in adult performance caused by factors such as diet, exercise, and normal aging. The fly is a unique and valuable system for the study of such complex, long-term interactions, as it is the only invertebrate genetic model system with a working heart developmentally homologous to the vertebrate heart. Thus, the fly model combines the advantages of invertebrate genetics (such as large populations, facile molecular genetic techniques, and short lifespan) with physiological measurement techniques that allow meaningful comparisons with data from vertebrate model systems. As such, the fly model is well situated to make important contributions to the understanding of complicated interactions between environmental factors and genetics in the long-term regulation of cardiac performance. PMID:21377627

  16. 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 ...

  17. 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

  18. 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

  19. Dynamic reciprocity of sodium and potassium channel expression in a macromolecular complex controls cardiac excitability and arrhythmia.

    PubMed

    Milstein, Michelle L; Musa, Hassan; Balbuena, Daniela Ponce; Anumonwo, Justus M B; Auerbach, David S; Furspan, Philip B; Hou, Luqia; Hu, Bin; Schumacher, Sarah M; Vaidyanathan, Ravi; Martens, Jeffrey R; Jalife, José

    2012-07-31

    The cardiac electrical impulse depends on an orchestrated interplay of transmembrane ionic currents in myocardial cells. Two critical ionic current mechanisms are the inwardly rectifying potassium current (I(K1)), which is important for maintenance of the cell resting membrane potential, and the sodium current (I(Na)), which provides a rapid depolarizing current during the upstroke of the action potential. By controlling the resting membrane potential, I(K1) modifies sodium channel availability and therefore, cell excitability, action potential duration, and velocity of impulse propagation. Additionally, I(K1)-I(Na) interactions are key determinants of electrical rotor frequency responsible for abnormal, often lethal, cardiac reentrant activity. Here, we have used a multidisciplinary approach based on molecular and biochemical techniques, acute gene transfer or silencing, and electrophysiology to show that I(K1)-I(Na) interactions involve a reciprocal modulation of expression of their respective channel proteins (Kir2.1 and Na(V)1.5) within a macromolecular complex. Thus, an increase in functional expression of one channel reciprocally modulates the other to enhance cardiac excitability. The modulation is model-independent; it is demonstrable in myocytes isolated from mouse and rat hearts and with transgenic and adenoviral-mediated overexpression/silencing. We also show that the post synaptic density, discs large, and zonula occludens-1 (PDZ) domain protein SAP97 is a component of this macromolecular complex. We show that the interplay between Na(v)1.5 and Kir2.1 has electrophysiological consequences on the myocardium and that SAP97 may affect the integrity of this complex or the nature of Na(v)1.5-Kir2.1 interactions. The reciprocal modulation between Na(v)1.5 and Kir2.1 and the respective ionic currents should be important in the ability of the heart to undergo self-sustaining cardiac rhythm disturbances. PMID:22509027

  20. 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

  1. 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

  2. [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

  3. 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

  4. 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

  5. [Cardiac potassium channels: molecular structure, physiology, pathophysiology and therapeutic implications].

    PubMed

    Mironov, N Iu; Golitsyn, S P

    2013-01-01

    Potassium channels and currents play essential roles in cardiac repolarization. Potassium channel blockade by class III antiarrhythmic drugs prolongs cardiac repolarization and results in termination and prevention of cardiac arrhythmias. Excessive inhomogeneous repolarization prolongation may lead to electrical instability and proarrhythmia (Torsade de Pointes tachycardia). This review focuses on molecular structure, physiology, pathophysiology and therapeutic potential of potassium channels of cardiac conduction system and myocardium providing information on recent findings in pathogenesis of cardiac arrhythmias, including inherited genetic abnormalities, and future perspectives. PMID:24654438

  6. Mechanoregulation of cardiac myofibroblast differentiation: implications for cardiac fibrosis and therapy.

    PubMed

    Yong, Kar Wey; Li, YuHui; Huang, GuoYou; Lu, Tian Jian; Safwani, Wan Kamarul Zaman Wan; Pingguan-Murphy, Belinda; Xu, Feng

    2015-08-15

    Cardiac myofibroblast differentiation, as one of the most important cellular responses to heart injury, plays a critical role in cardiac remodeling and failure. While biochemical cues for this have been extensively investigated, the role of mechanical cues, e.g., extracellular matrix stiffness and mechanical strain, has also been found to mediate cardiac myofibroblast differentiation. Cardiac fibroblasts in vivo are typically subjected to a specific spatiotemporally changed mechanical microenvironment. When exposed to abnormal mechanical conditions (e.g., increased extracellular matrix stiffness or strain), cardiac fibroblasts can undergo myofibroblast differentiation. To date, the impact of mechanical cues on cardiac myofibroblast differentiation has been studied both in vitro and in vivo. Most of the related in vitro research into this has been mainly undertaken in two-dimensional cell culture systems, although a few three-dimensional studies that exist revealed an important role of dimensionality. However, despite remarkable advances, the comprehensive mechanisms for mechanoregulation of cardiac myofibroblast differentiation remain elusive. In this review, we introduce important parameters for evaluating cardiac myofibroblast differentiation and then discuss the development of both in vitro (two and three dimensional) and in vivo studies on mechanoregulation of cardiac myofibroblast differentiation. An understanding of the development of cardiac myofibroblast differentiation in response to changing mechanical microenvironment will underlie potential targets for future therapy of cardiac fibrosis and failure. PMID:26092987

  7. Cardiomyocyte Circadian Oscillations Are Cell-Autonomous, Amplified by β-Adrenergic Signaling, and Synchronized in Cardiac Ventricle Tissue

    PubMed Central

    Welsh, David K.

    2016-01-01

    Circadian clocks impact vital cardiac parameters such as blood pressure and heart rate, and adverse cardiac events such as myocardial infarction and sudden cardiac death. In mammals, the central circadian pacemaker, located in the suprachiasmatic nucleus of the hypothalamus, synchronizes cellular circadian clocks in the heart and many other tissues throughout the body. Cardiac ventricle explants maintain autonomous contractions and robust circadian oscillations of clock gene expression in culture. In the present study, we examined the relationship between intrinsic myocardial function and circadian rhythms in cultures from mouse heart. We cultured ventricular explants or dispersed cardiomyocytes from neonatal mice expressing a PER2::LUC bioluminescent reporter of circadian clock gene expression. We found that isoproterenol, a β-adrenoceptor agonist known to increase heart rate and contractility, also amplifies PER2 circadian rhythms in ventricular explants. We found robust, cell-autonomous PER2 circadian rhythms in dispersed cardiomyocytes. Single-cell rhythms were initially synchronized in ventricular explants but desynchronized in dispersed cells. In addition, we developed a method for long-term, simultaneous monitoring of clock gene expression, contraction rate, and basal intracellular Ca2+ level in cardiomyocytes using PER2::LUC in combination with GCaMP3, a genetically encoded fluorescent Ca2+ reporter. In contrast to robust PER2 circadian rhythms in cardiomyocytes, we detected no rhythms in contraction rate and only weak rhythms in basal Ca2+ level. In summary, we found that PER2 circadian rhythms of cardiomyocytes are cell-autonomous, amplified by adrenergic signaling, and synchronized by intercellular communication in ventricle explants, but we detected no robust circadian rhythms in contraction rate or basal Ca2+. PMID:27459195

  8. Number needed to treat = six: therapeutic hypothermia following cardiac arrest – an effective and cheap approach to save lives

    PubMed Central

    Böttiger, Bernd W; Schneider, Andreas; Popp, Erik

    2007-01-01

    In 2005, the European Resuscitation Council (ERC) guidelines stated: Unconscious adult patients with spontaneous circulation after out-of-hospital ventricular fibrillation cardiac arrest should be cooled to 32 to 34°C for 12 to 24 hours. Patients with cardiac arrest from a non-shockable rhythm, in-hospital patients and children may also benefit from hypothermia. There is no argument to wait. We have to treat the next unconscious cardiac arrest patient with hypothermia. PMID:17850681

  9. [Pharmaca Induced Cardiac Injury].

    PubMed

    Haen, Ekkehard

    2016-01-01

    Many drugs influence vital functions via the sympathetic and the parasympathetic system. Besides that hypersensitivity reactions and reactions by chemical radicals that arise in drug metabolism may directly harm the heart muscle cell. Cardiac adverse drug reactions (ADR) result in disturbances of the heart rhythm, negative inotropic effects, direct damage to the heart muscle cell, and reduced perfusion of heart tissue. Their importance is often neglected because pharmacologically similar drugs are licensed for completely different indications. This is of particular interest if more drugs are prescribed in combination. Now these effects may add up to pharmacodynamic drug-drug-interactions. Data banks like PSIAConline (www.psiac.de), individualization of drug prescription by therapeutic drug monitoring (TDM) combined with a clinical pharmacological report (www.konbest.de), as well as drug information systems such as AGATE (www.amuep-agate.de) are today of help not just to recognize such drug risks, but also to find professional and evidence based solutions for it. PMID:26800070

  10. 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

  11. Cardiac sarcoidosis

    PubMed Central

    Smedema, J.P.; Zondervan, P.E.; van Hagen, P.; ten Cate, F.J.; Bresser, P.; Doubell, A.F.; Pattynama, P.; Hoogsteden, H.C.; Balk, A.H.M.M.

    2002-01-01

    Sarcoidosis is a multi-system granulomatous disorder of unknown aetiology. Symptomatic cardiac involvement occurs in approximately 5% of patients. The prevalence of sarcoidosis in the Netherlands is unknown, but estimated to be approximately 20 per 100,000 population (3200 patients). We report on five patients who presented with different manifestations of cardiac sarcoidosis, and give a brief review on the current management of this condition. Magnetic Resonance Imaging (MRI) can be of great help in diagnosing this condition as well as in the follow-up of the response to therapy. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:25696121

  12. 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.

  13. 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

  14. Non-Linear Dynamics of Cardiac Alternans: Subcellular to Tissue-Level Mechanisms of Arrhythmia

    PubMed Central

    Gaeta, Stephen A.; Christini, David J.

    2012-01-01

    Cardiac repolarization alternans is a rhythm disturbance of the heart in which rapid stimulation elicits a beat-to-beat alternation in the duration of action potentials and magnitude of intracellular calcium transients in individual cardiac myocytes. Although this phenomenon has been identified as a potential precursor to dangerous reentrant arrhythmias and sudden cardiac death, significant uncertainty remains regarding its mechanism and no clinically practical means of halting its occurrence or progression currently exists. Cardiac alternans has well-characterized tissue, cellular, and subcellular manifestations, the mechanisms and interplay of which are an active area of research. PMID:22783195

  15. 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 ...

  16. 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 ...

  17. 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

  18. Sudden infant death syndrome and abnormal metabolism of thiamin.

    PubMed

    Lonsdale, Derrick

    2015-12-01

    Although it has been generally accepted that moving the infant from the prone to the supine position has solved the problem of sudden infant death syndrome (SIDS), it has been hypothesized that this is an insufficient explanation and that a mixture of genetic risk, some form of stressful incident and marginal brain metabolism is proportionately required. It is suggested that each of these three variables, with dominance in one or more of them, act together in the common etiology. Much has been written about the association of thiamin and magnesium but the finding of extremely high concentrations of serum thiamin in SIDs victims has largely caused rejection of thiamin as being involved in the etiology. The publication of abnormal brainstem auditory evoked potentials strongly suggests that there are electrochemical changes in the brainstem affecting the mechanisms of automatic breathing and the control of cardiac rhythm. The brainstem, cerebellum and limbic system of the brain are known to be highly sensitive to thiamin deficiency (pseudo-hypoxia) and the pathophysiology is similar to a mild continued deprivation of oxygen. Little attention has been paid to the complex metabolism of thiamin. Dietary thiamin requires the cooperation of the SLC19 family of thiamin transporters for its absorption into cells and recent information has shown that transporter SNPs may be relatively common and can be expected to increase genetic risk. Thiamin must be phosphorylated to synthesize thiamin pyrophosphate (TPP), well established in its vital action in glucose metabolism. TPP is also a cofactor for the enzyme 2-hydroxyacyl-CoA lyase (HACL1) in the peroxisome, emphasizing its importance in alpha oxidation and plasmalogen synthesis in cell membrane physiology. The importance of thiamine triphosphate (TTP) in energy metabolism is still largely unknown. Thiamin metabolism has been implicated in hyperemesis gravidarum and iatrogenic Wernicke encephalopathy has been reported when the

  19. Vitamin D and Cardiac Differentiation.

    PubMed

    Kim, Irene M; Norris, Keith C; Artaza, Jorge N

    2016-01-01

    Calcitriol (1,25-dihydroxycholecalciferol or 1,25-D3) is the hormonally active metabolite of vitamin D. Experimental studies of vitamin D receptors and 1,25-D3 establish calcitriol to be a critical regulator of the structure and function of the heart. Clinical studies link vitamin D deficiency with cardiovascular disease (CVD). Emerging evidence demonstrates that calcitriol is highly involved in CVD-related signaling pathways, particularly the Wnt signaling pathway. Addition of 1,25-D3 to cardiomyocyte cells and examination of its effects on cardiomyocytes and mainly Wnt11 signaling allowed the specific characterization of the role of calcitriol in cardiac differentiation. 1,25-D3 is demonstrated to: (i) inhibit cell proliferation without promoting apoptosis; (ii) decrease expression of genes related to the regulation of the cell cycle; (iii) promote formation of cardiomyotubes; (iv) induce expression of casein kinase-1-α1, a negative regulator of the canonical Wnt signaling pathway; and (v) increase expression of noncanonical Wnt11, which has been recognized to induce cardiac differentiation during embryonic development and in adult cells. Thus, it appears that vitamin D promotes cardiac differentiation through negative modulation of the canonical Wnt signaling pathway and upregulation of noncanonical Wnt11 expression. Future work to elucidate the role(s) of vitamin D in cardiovascular disorders will hopefully lead to improvement and potentially prevention of CVD, including abnormal cardiac differentiation in settings such as postinfarction cardiac remodeling. PMID:26827957

  20. 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.

  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. Therapeutic Hypothermia after Prolonged Cardiac Arrest: Case Report with Review of Literature

    PubMed Central

    Yadav, Sankalp; Garg, Nitin

    2015-01-01

    Patients who survive cardiac arrest often develop severe neurological dysfunction due to the hypoxic brain injury and reperfusion induced cell death. Therapeutic hypothermia (TH) has become a standard therapy of cerebral protection following the successful return of spontaneous circulation in patients of out-of-hospital cardiac arrest, according to American heart association guidelines. This is a case report of a 30-year-old patient who developed in-hospital cardiac arrest and was revived after prolonged cardiopulmonary resuscitation (CPR) and also required primary angioplasty. TH was then established with local measures for 24 hours for cerebral protection. The patient was gradually and successfully weaned off from ventilator with no neurological impairment. There is an increasing evidence of TH and its protective mechanisms in patients with non-shockable arrest rhythms with particular emphasis on neurological outcomes. This article emphasizes the role of TH in every successful CPR irrespective of the cardiac rhythm. PMID:26500937

  17. 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…

  18. Cardiac involvement in myotonic dystrophy

    PubMed Central

    Khalighi, Koroush; Kodali, Archana; Thapamagar, Suman B.; Walker, Stanley R.

    2015-01-01

    Background Myotonic dystrophy (DM) is an inherited progressive muscle disorder caused by defects in muscle proteins. As the incidence of this condition is low, not many are familiar with the multisystem involvement. At times, cardiac disease may even be the predominant manifestation in the form of arrhythmias, conduction defects, and cardiomyopathies. The progression of the disease can lead to sudden, unpredictable death. Thus, it is important to identify this subgroup and treat accordingly. Objective To identify patients with DM and assess their risk for sudden cardiac death. Methods Nine patients previously diagnosed with muscular dystrophy were evaluated by cardiologists for various reasons, from a general follow-up to cardiac arrest. All of them had electrocardiograms (EKG) and 2-D echocardiograms, and seven of them had further electrophysiological (EP) studies. Results Of the nine patients with DM, eight had EKG evidence of conduction abnormalities ranging from first-degree heart block to complete heart block. Of the seven who had EP studies, five had inducible ventricular tachycardia requiring immediate cardioversion and implantable cardioverter defibrillator (ICD) implant. Two of them underwent permanent pacemaker placement due to complete heart block and infra-Hissian block. The remaining two patients opted for a conservative approach with yearly EKG monitoring. Conclusion Because one-third of the cardiac deaths in patients with DM are sudden, there is a strong need to identify these patients and intervene in those at high risk. Prophylactic pacemaker placement is recommended even in those with minimal conduction system abnormality. However, the common practice is to identify patients at high risk of conduction abnormalities by EP studies and then provide them with prophylactic invasive strategies. PMID:25656662

  19. Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery

    PubMed Central

    Goldsmith, Yulia; Chan, Jacqueline; Iskandir, Marina; Gulkarov, Iosif; Tortolani, Anthony; Brener, Sorin J.; Sacchi, Terrence J.; Heitner, John F.

    2015-01-01

    Background The significance of right ventricular ejection fraction (RVEF), independent of left ventricular ejection fraction (LVEF), following isolated coronary artery bypass grafting (CABG) and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR), independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery. Methods From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female) were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered <35% and <45%, respectively. Elective primary procedures include CABG (56%) and valve (44%). Thirty-day outcomes were perioperative complications, length of stay, cardiac re-hospitalizations and early mortaility; long-term (> 30 days) outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months. Findings Forty-eight patients had reduced RVEF (mean 25%) and 61 patients had normal RVEF (mean 50%) (p<0.001). Fifty-four patients had reduced LVEF (mean 30%) and 55 patients had normal LVEF (mean 59%) (p<0.001). Patients with reduced RVEF had a higher incidence of long-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, p<0.05). Abnormal RVEF was a predictor for long-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], p<0.03). Reduced LVEF did not influence long-term cardiac re-hospitalization. Conclusion Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures. PMID:26197273

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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.

  5. 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…

  6. 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

  7. 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.

  8. Cardiac amyloidosis: updates in diagnosis and management.

    PubMed

    Mohty, Dania; Damy, Thibaud; Cosnay, Pierre; Echahidi, Najmeddine; Casset-Senon, Danielle; Virot, Patrice; Jaccard, Arnaud

    2013-10-01

    Amyloidosis is a severe systemic disease. Cardiac involvement may occur in the three main types of amyloidosis (acquired monoclonal light-chain, hereditary transthyretin and senile amyloidosis) and has a major impact on prognosis. Imaging the heart to characterize and detect early cardiac involvement is one of the major aims in the assessment of this disease. Electrocardiography and transthoracic echocardiography are important diagnostic and prognostic tools in patients with cardiac involvement. Cardiac magnetic resonance imaging better characterizes myocardial involvement, functional abnormalities and amyloid deposition due to its high spatial resolution. Nuclear imaging has a role in the diagnosis of transthyretin amyloid cardiomyopathy. Cardiac biomarkers are now used for risk stratification and staging of patients with light-chain systemic amyloidosis. Different types of cardiac complications may occur, including diastolic followed by systolic heart failure, atrial and/or ventricular arrhythmias, conduction disturbances, embolic events and sometimes sudden death. Senile amyloid and hereditary transthyretin amyloid cardiomyopathy have better prognoses than light-chain amyloidosis. Cardiac treatment of heart failure is usually ineffective and is often poorly tolerated because of its hypotensive and bradycardiac effects. The three main types of amyloid disease, despite their similar cardiac appearance, have specific new aetiological treatments that may change the prognosis of this disease. Cardiologists should be aware of this disease to allow early treatment. PMID:24070600

  9. Cardiac models in drug discovery and development: a review.

    PubMed

    Amanfu, Robert K; Saucerman, Jeffrey J

    2011-01-01

    Cardiovascular diseases are among the leading causes of death in the developed world. Developing novel therapies for diseases like heart failure is crucial, but this is hampered by the high attrition rate in drug development. The withdrawal of drugs at the final hurdle of approval is mostly because of their unpredictable effects on normal cardiac rhythm. The advent of cardiac computational modeling in the last 5 decades has aided the understanding of heart function significantly. Recently, these models increasingly have been applied toward designing and understanding therapies for cardiac disease. This article will discuss how cellular models of electrophysiology, cell signaling, and metabolism have been used to investigate pharmacologic therapies for cardiac diseases including arrhythmia, ischemia, and heart failure. PMID:22196160

  10. Cardiac optogenetics

    PubMed Central

    2013-01-01

    Optogenetics is an emerging technology for optical interrogation and control of biological function with high specificity and high spatiotemporal resolution. Mammalian cells and tissues can be sensitized to respond to light by a relatively simple and well-tolerated genetic modification using microbial opsins (light-gated ion channels and pumps). These can achieve fast and specific excitatory or inhibitory response, offering distinct advantages over traditional pharmacological or electrical means of perturbation. Since the first demonstrations of utility in mammalian cells (neurons) in 2005, optogenetics has spurred immense research activity and has inspired numerous applications for dissection of neural circuitry and understanding of brain function in health and disease, applications ranging from in vitro to work in behaving animals. Only recently (since 2010), the field has extended to cardiac applications with less than a dozen publications to date. In consideration of the early phase of work on cardiac optogenetics and the impact of the technique in understanding another excitable tissue, the brain, this review is largely a perspective of possibilities in the heart. It covers the basic principles of operation of light-sensitive ion channels and pumps, the available tools and ongoing efforts in optimizing them, overview of neuroscience use, as well as cardiac-specific questions of implementation and ideas for best use of this emerging technology in the heart. PMID:23457014

  11. Cardiac Surgery

    PubMed Central

    Weisse, Allen B.

    2011-01-01

    Well into the first decades of the 20th century, medical opinion held that any surgical attempts to treat heart disease were not only misguided, but unethical. Despite such reservations, innovative surgeons showed that heart wounds could be successfully repaired. Then, extracardiac procedures were performed to correct patent ductus arteriosus, coarctation of the aorta, and tetralogy of Fallot. Direct surgery on the heart was accomplished with closed commissurotomy for mitral stenosis. The introduction of the heart-lung machine and cardiopulmonary bypass enabled the surgical treatment of other congenital and acquired heart diseases. Advances in aortic surgery paralleled these successes. The development of coronary artery bypass grafting greatly aided the treatment of coronary heart disease. Cardiac transplantation, attempts to use the total artificial heart, and the application of ventricular assist devices have brought us to the present day. Although progress in the field of cardiovascular surgery appears to have slowed when compared with the halcyon times of the past, substantial challenges still face cardiac surgeons. It can only be hoped that sufficient resources and incentive can carry the triumphs of the 20th century into the 21st. This review covers past developments and future opportunities in cardiac surgery. PMID:22163121

  12. 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

  13. Heterotaxia syndrome: the role of screening for intestinal rotation abnormalities

    PubMed Central

    Choi, M; Borenstein, S; Hornberger, L; Langer, J

    2005-01-01

    Background: Heterotaxia syndrome involves multiple anomalies, including cardiac malformations and intestinal rotation abnormalities. Most authors recommend routine radiological evaluation, with laparotomy and Ladd procedure if a rotation abnormality is found. Aims: To determine if routine radiological screening is necessary, and if there is a group of children that can safely be managed expectantly. Methods: Retrospective chart review of all children with heterotaxia syndrome from 1968 to 2002. Results: Complete data were available for 177 patients. Twenty five (14%) had neonatal gastrointestinal symptoms (feeding intolerance, vomiting). Eleven of these had gastrointestinal contrast studies, of which seven were abnormal and led to surgery. Of the 152 asymptomatic neonates, nine had radiological screening and six of these were abnormal. Only one was thought to have a narrow based mesentery, but did not undergo surgery due to cardiac disease. There were no intestinal complications on follow up in this group. The other 143 asymptomatic children did not undergo radiological screening and were closely followed. Four subsequently developed gastrointestinal symptoms and had contrast studies; only one of these had malrotation and underwent a Ladd procedure. Of the remaining 139 patients who remained asymptomatic, 60 (43%) died of cardiac disease and none developed intestinal symptoms or complications related to malrotation on follow up. Conclusion: Asymptomatic children with heterotaxia syndrome have a low risk of adverse outcome related to intestinal rotation abnormalities. Routine screening may not be necessary as long as close follow up is done, and prompt investigation is performed for those that develop gastrointestinal symptomatology. PMID:15890694

  14. Epigenetic mechanisms underlying cardiac degeneration and regeneration*

    PubMed Central

    Chaturvedi, Pankaj; Tyagi, Suresh C.

    2014-01-01

    Epigenetic modifications which are defined by DNA methylation, histone modifications and microRNA mediated gene regulation, have been found to be associated with cardiac dysfunction and cardiac regeneration but the mechanisms are unclear. MicroRNA therapies have been proposed for cardiac regeneration and proliferation of stem cells into cardiomyocytes. Cardiovascular disorders are represented by abnormal methylation of CpG islands and drugs that inhibit DNA methyl transferases such as 5-methyl Aza cytidine are under trials. Histone modifications which include acetylation, methylation, phosphorylation, ADP ribosylation, sumoylation and biotinylation are represented within abnormal phenotypes of cardiac hypertrophy, cardiac development and contractility. MicroRNAs have been used efficiently to epigenetically reprogram fibroblasts into cardiomyocytes. MicroRNAs represent themselves as potential biomarkers for early detection of cardiac disorders which are difficult to diagnose and are captured at later stages. Because microRNAs regulate circadian genes, for example a nocturnin gene of circadian clockwork is regulated by mir122, they have profound role in regulating biological clock and this may explain the high cardiovascular risk during the morning time. This review highlights the role of epigenetics which can be helpful in disease management strategies. PMID:24636549

  15. [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.

  16. [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

  17. Myocardial perfusion abnormalities in asymptomatic patients with systemic lupus erythematosus

    SciTech Connect

    Hosenpud, J.D.; Montanaro, A.; Hart, M.V.; Haines, J.E.; Specht, H.D.; Bennett, R.M.; Kloster, F.E.

    1984-08-01

    Accelerated coronary artery disease and myocardial infarction in young patients with systemic lupus erythematosus is well documented; however, the prevalence of coronary involvement is unknown. Accordingly, 26 patients with systemic lupus were selected irrespective of previous cardiac history to undergo exercise thallium-201 cardiac scintigraphy. Segmental perfusion abnormalities were present in 10 of the 26 studies (38.5 percent). Five patients had reversible defects suggesting ischemia, four patients had persistent defects consistent with scar, and one patient had both reversible and persistent defects in two areas. There was no correlation between positive thallium results and duration of disease, amount of corticosteroid treatment, major organ system involvement or age. Only a history of pericarditis appeared to be associated with positive thallium-201 results (p less than 0.05). It is concluded that segmental myocardial perfusion abnormalities are common in patients with systemic lupus erythematosus. Whether this reflects large-vessel coronary disease or small-vessel abnormalities remains to be determined.

  18. 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

  19. "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)

  20. 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, ...

  1. 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 ...

  2. Objective cardiac markers and cerebrovascular lesions in Indian seniors.

    PubMed

    Charles, Stephanie H; Tow, Amanda C; Verghese, Joe

    2014-09-01

    Cardiovascular risk factors are implicated in cerebrovascular disease, resulting in cognitive impairment. This study investigated the relationship between objective cardiac markers and cerebral changes in older Indian adults with and without dementia. Dementia patients with major electrocardiographic (EKG) abnormalities were 8.19 times more likely to have evidence of stroke on magnetic resonance imaging (MRI) compared with patients with no EKG abnormalities (p<.05). The relationship between major EKG abnormalities and stroke on MRI was not significant for patients without dementia. Objective cardiac markers may identify MRI cerebrovascular lesions in patients with dementia, and thus guide neuroimaging allocation in resource-poor areas. PMID:25107661

  3. The surdo-cardiac syndrome and therapeutic observations

    PubMed Central

    Olley, P. M.; Fowler, R. S.

    1970-01-01

    First recognized in 1957, the surdo-cardiac syndrome includes congenital deafness, prolonged QT interval, and a high incidence of syncope and sudden death. Haemodynamic studies in two patients were normal except for an abnormal wave during left ventricular diastole probably related to abnormal left ventricular relaxation. The syncopal attacks are based on cardiac arrhythmias: both ventricular fibrillation and asystole may occur. Abnormal adrenergic stimulation of the heart is probably responsible. Propranolol appears to be effective in preventing the syncopal attacks. Artificial pacemaking provoked ventricular fibrillation in one patient and seems contraindicated. Images PMID:5433307

  4. Hypothermic cardiac arrest: an 11 year review of ED management and outcome.

    PubMed

    Brunette, D D; McVaney, K

    2000-07-01

    The purpose of this study was to examine the emergency department (ED) management of hypothermic cardiac arrest and its outcome. The medical records of all patients with hypothermic cardiac arrest treated in the ED from January 1, 1988 to January 31, 1999 were retrospectively reviewed. Data collected included initial body temperature, serum potassium, methods of rewarming, return of perfusing rhythm, and morbidity and mortality. Data were analyzed by descriptive methods. Eleven patients were treated in the ED resuscitation room for hypothermic cardiac arrest. Six patients were found in cardiac arrest in the field, one patient arrested during transport, and four patients arrested after ED arrival. The average initial temperature was 79.1 degrees F (range 69.0 degrees F to 86.7 degrees F). Seven patients received an ED thoracotomy with internal cardiac massage and warm mediastinal irrigation. Four patients had airway management in the ED and then direct transport to the operating room for cardiac bypass rewarming. Three of the seven patients who received an ED thoracotomy subsequently went to intraoperative cardiac bypass rewarming. Five of the seven (71.4%) patients who received an ED thoracotomy survived, versus none of the four patients (0%) who went directly to intraoperative cardiac bypass. A direct comparison of immediate ED thoracotomy versus intraoperative cardiac bypass without ED thoracotomy is cautiously made as this was an unmatched and nonrandomized study. Three of the surviving patients underwent intraoperative cardiac bypass rewarming after receiving an ED thoracotomy. In two of these patients a perfusing rhythm had been established after thoracotomy in the ED and before transport to the operating room for cardiac bypass. Only one of seven (14.3%) patients who arrested prehospital survived versus four of four (100%) who arrested in the ED. ED thoracotomy with internal cardiac massage and mediastinal irrigation rewarming is effective in the management

  5. 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

  6. Biological therapies for cardiac arrhythmias: can genes and cells replace drugs and devices?

    PubMed

    Cho, Hee Cheol; Marbán, Eduardo

    2010-03-01

    Cardiac rhythm disorders reflect failures of impulse generation and/or conduction. With the exception of ablation methods that yield selective endocardial destruction, present therapies are nonspecific and/or palliative. Progress in understanding the underlying biology opens up prospects for new alternatives. This article reviews the present state of the art in gene- and cell-based therapies to correct cardiac rhythm disturbances. We begin with the rationale for such approaches, briefly discuss efforts to address aspects of tachyarrhythmia, and review advances in creating a biological pacemaker to cure bradyarrhythmia. Insights gained bring the field closer to a paradigm shift away from devices and drugs, and toward biologics, in the treatment of rhythm disorders. PMID:20203316

  7. 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

  8. 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

  9. [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

  10. Cardiac pacing and aviation.

    PubMed

    Toff, W D; Edhag, O K; Camm, A J

    1992-12-01

    Certain applicants with stable disturbances of rhythm or conduction requiring cardiac pacing, in whom no other disqualifying condition is present, may be considered fit for medical certification restricted to multi-crew operations. The reliability of modern pacing systems appears adequate to permit restricted certification even in pacemaker dependent subjects except for certain models of pacemakers and leads known to be at increased risk of failure. These are to be avoided. There is little evidence to suggest that newer devices are any more reliable than their predecessors. Single and dual chamber systems appear to have similar reliability up to 4 years, after which time significant attrition of dual chamber devices occurs, principally due to battery depletion. All devices require increased scrutiny as they approach their end of life as predicted from longevity data and pacing characteristics. Unipolar and bipolar leads are of similar reliability, apart from a number of specific bipolar polyurethane leads which have been identified. Atrial leads, particularly those without active fixation, are less secure than ventricular leads and applicants who are dependent on atrial sensing or pacing should be denied certification. Bipolar leads are to be preferred due to the lower risk of myopotential and exogenous EMI. Sensor-driven adaptive-rate pacing systems using active sensors may have reduced longevity and require close scrutiny. Activity-sensing devices using piezoelectric crystal sensors may be subject to significant rate rises in rotary wing aircraft. The impracticality of restricted certification in helicopters will, in any event, preclude certification. Such devices would best be avoided in hovercraft (air cushioned vehicle) pilots. Only minor rate rises are likely in fixed-wing aircraft which are unlikely to be of significance. Anti-tachycardia devices and implanted defibrillators are inconsistent with any form of certification to fly. PMID:1493823

  11. Mechanisms of Sudden Cardiac Death: Oxidants and Metabolism

    PubMed Central

    Yang, Kai-Chien; Kyle, John W.; Makielski, Jonathan C.; Dudley, Samuel C.

    2015-01-01

    Ventricular arrhythmia is the leading cause of sudden cardiac death (SCD). Deranged cardiac metabolism and abnormal redox state during cardiac diseases foment arrhythmogenic substrates through direct or indirect modulation of cardiac ion channel/transporter function. This review presents current evidence on the mechanisms linking metabolic derangement and excessive oxidative stress to ion channel/transporter dysfunction that predisposes to ventricular arrhythmias and SCD. As conventional anti-arrhythmic agents aiming at ion channels have proven challenging to use, targeting arrhythmogenic metabolic changes and redox imbalance may provide novel therapeutics to treat or prevent life-threatening arrhythmias and SCD. PMID:26044249

  12. 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.

  13. Three Dimension Filamentous Human Cardiac Tissue Model

    PubMed Central

    Ma, Zhen; Koo, Sangmo; Finnegan, Micaela A.; Loskill, Peter; Huebsch, Nathaniel; Marks, Natalie C.; Conklin, Bruce R.; Grigoropoulos, Costas P.; Healy, Kevin E.

    2013-01-01

    A human in vitro cardiac tissue model would be a significant advancement for understanding, studying, and developing new strategies for treating cardiac arrhythmias and related cardiovascular diseases. We developed an in vitro model of three-dimensional (3D) human cardiac tissue by populating synthetic filamentous matrices with cardiomyocytes derived from healthy wild-type volunteer (WT) and patient-specific long QT syndrome type 3 (LQT3) induced pluripotent stem cells (iPS-CMs) to mimic the condensed and aligned human ventricular myocardium. Using such a highly controllable cardiac model, we studied the contractility malfunctions associated with the electrophysiological consequences of LQT3 and their response to a panel of drugs. By varying the stiffness of filamentous matrices, LQT3 iPS-CMs exhibited different level of contractility abnormality and susceptibility to drug-induced cardiotoxicity. PMID:24268663

  14. 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.

  15. 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

  16. 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

  17. 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

  18. Cardiac abnormalities in youth with obesity and type 2 diabetes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Childhood obesity has been linked to cardiovascular disease (CVD) risk in adulthood. Of great concern is the expected increase in the population's CVD burden in relation to childhood obesity. This is compounded by the risk related to chronic hyperglycemia exposure in youth with type 2 diabetes. We h...

  19. 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

  20. Cardiac rehabilitation.

    PubMed

    Ehsani, A A

    1984-02-01

    Exercise training is a major, and the most important, component of cardiac rehabilitation. Besides providing psychological benefits and promoting a "sense of well being," it elicits a number of adaptations in patients with ischemic heart disease. Among the clinically important adaptations are changes in the trained skeletal muscles and autonomic nervous system, resulting not only in increased maximum exercise capacity but also a slower heart rate and, at times, a lower systolic blood pressure during submaximal exercise. The reduction in the rate pressure product decreases myocardial O2 demand at any given submaximal exercise intensity and may thus alleviate myocardial ischemia and angina in patients with coronary artery disease. These adaptive responses occur even with a relatively modest exercise intensity. Although short-term exercise training of moderate intensity has not been reported to result in improvement in left ventricular performance, recent data suggest that exercise training of higher intensity and longer duration (12 months or longer) than has conventionally been used in cardiac rehabilitation programs may favorably affect the heart. This is characterized by improvements in left ventricular function, diminished electrocardiographic criteria of myocardial ischemia and increased stroke volume during exercise. Modest weight reduction accompanies regularly performed prolonged exercise training. It is important, however, to recognize that high-intensity exercise programs are suitable for only some patients with coronary artery disease who are stable and should be used only under strict medical supervision. PMID:6400004

  1. Mechanistically based mapping of human cardiac fibrillation

    PubMed Central

    Zaman, Junaid A. B.

    2016-01-01

    Abstract The mechanisms underpinning human cardiac fibrillation remain elusive. In his 1913 paper ‘On dynamic equilibrium in the heart’, Mines proposed that an activation wave front could propagate repeatedly in a circle, initiated by a stimulus in the vulnerable period. While the dynamics of activation and recovery are central to cardiac fibrillation, these physiological data are rarely used in clinical mapping. Fibrillation is a rapid irregular rhythm with spatiotemporal disorder resulting from two fundamental mechanisms – sources in preferred cardiac regions or spatially diffuse self‐sustaining activity, i.e. with no preferred source. On close inspection, however, this debate may also reflect mapping technique. Fibrillation is initiated from triggers by regional dispersion in repolarization, slow conduction and wavebreak, then sustained by non‐uniform interactions of these mechanisms. Notably, optical mapping of action potentials in atrial fibrillation (AF) show spiral wave sources (rotors) in nearly all studies including humans, while most traditional electrogram analyses of AF do not. Techniques may diverge in fibrillation because electrograms summate non‐coherent waves within an undefined field whereas optical maps define waves with a visually defined field. Also fibrillation operates at the limits of activation and recovery, which are well represented by action potentials while fibrillatory electrograms poorly represent repolarization. We conclude by suggesting areas for study that may be used, until such time as optical mapping is clinically feasible, to improve mechanistic understanding and therapy of human cardiac fibrillation. PMID:26607671

  2. Neurohumoral indicators of efficacy radiofrequency cardiac denervation

    NASA Astrophysics Data System (ADS)

    Evtushenko, A. V.; Evtushenko, V. V.; Saushkina, Yu. V.; Lishmanov, Yu. B.; Pokushalov, E. A.; Sergeevichev, D. S.; Gusakova, A. M.; Suslova, T. E.; Dymbrylova, O. N.; Bykov, A. N.; Syryamkin, V. I.; Kistenev, Yu. V.; Anfinogenova, Ya. D.; Smyshlyaev, K. A.; Lotkov, A. I.; Kurlov, I. O.

    2015-11-01

    In this study, we compared pre- and postoperative parameters of the cardiac sympathetic innervation. The aim of the study was to examine the approaches to evaluating the quality of radiofrequency (RF)-induced cardiac denervation by using non-invasive and laboratory methods. The study included 32 people with long-lasting persistent atrial fibrillation (AF). The patients were divided into 2 groups according to the objectives of the study: group 1 (main) - 21 patients with mitral valve diseases, which simultaneously with radiofrequency ablation (RFA) AF carried out on the effects of the paraganglionic nervous plexuses by C. Pappone (2004) and N. Doll (2008) schemes. The second group (control) contained 11 patients with heart diseases in sinus rhythm (the RF denervation not been performed). All patients, who underwent surgical treatment, were received examination of cardiac sympathetic tone by using 123I-MIBG. All of them made blood analysis from ascending aorta and coronary sinus to determine the level of norepinephrine and its metabolites before and after cardiac denervation. Data of radionuclide examination are correlating with laboratory data.

  3. Mechanistically based mapping of human cardiac fibrillation.

    PubMed

    Narayan, Sanjiv M; Zaman, Junaid A B

    2016-05-01

    The mechanisms underpinning human cardiac fibrillation remain elusive. In his 1913 paper 'On dynamic equilibrium in the heart', Mines proposed that an activation wave front could propagate repeatedly in a circle, initiated by a stimulus in the vulnerable period. While the dynamics of activation and recovery are central to cardiac fibrillation, these physiological data are rarely used in clinical mapping. Fibrillation is a rapid irregular rhythm with spatiotemporal disorder resulting from two fundamental mechanisms - sources in preferred cardiac regions or spatially diffuse self-sustaining activity, i.e. with no preferred source. On close inspection, however, this debate may also reflect mapping technique. Fibrillation is initiated from triggers by regional dispersion in repolarization, slow conduction and wavebreak, then sustained by non-uniform interactions of these mechanisms. Notably, optical mapping of action potentials in atrial fibrillation (AF) show spiral wave sources (rotors) in nearly all studies including humans, while most traditional electrogram analyses of AF do not. Techniques may diverge in fibrillation because electrograms summate non-coherent waves within an undefined field whereas optical maps define waves with a visually defined field. Also fibrillation operates at the limits of activation and recovery, which are well represented by action potentials while fibrillatory electrograms poorly represent repolarization. We conclude by suggesting areas for study that may be used, until such time as optical mapping is clinically feasible, to improve mechanistic understanding and therapy of human cardiac fibrillation. PMID:26607671

  4. Neurohumoral indicators of efficacy radiofrequency cardiac denervation

    SciTech Connect

    Evtushenko, A. V. Evtushenko, V. V.; Saushkina, Yu. V.; Gusakova, A. M.; Suslova, T. E.; Dymbrylova, O. N.; Smyshlyaev, K. A.; Kurlov, I. O.; Lishmanov, Yu. B.; Anfinogenova, Ya. D.; Sergeevichev, D. S.; Bykov, A. N.; Syryamkin, V. I.; Kistenev, Yu. V.; Lotkov, A. I.; Pokushalov, E. A.

    2015-11-17

    In this study, we compared pre- and postoperative parameters of the cardiac sympathetic innervation. The aim of the study was to examine the approaches to evaluating the quality of radiofrequency (RF)-induced cardiac denervation by using non-invasive and laboratory methods. The study included 32 people with long-lasting persistent atrial fibrillation (AF). The patients were divided into 2 groups according to the objectives of the study: group 1 (main) - 21 patients with mitral valve diseases, which simultaneously with radiofrequency ablation (RFA) AF carried out on the effects of the paraganglionic nervous plexuses by C. Pappone (2004) and N. Doll (2008) schemes. The second group (control) contained 11 patients with heart diseases in sinus rhythm (the RF denervation not been performed). All patients, who underwent surgical treatment, were received examination of cardiac sympathetic tone by using {sup 123}I-MIBG. All of them made blood analysis from ascending aorta and coronary sinus to determine the level of norepinephrine and its metabolites before and after cardiac denervation. Data of radionuclide examination are correlating with laboratory data.

  5. Pediatric defibrillation after cardiac arrest: initial response and outcome

    PubMed Central

    Rodríguez-Núñez, Antonio; López-Herce, Jesús; García, Cristina; Domínguez, Pedro; Carrillo, Angel; Bellón, Jose María

    2006-01-01

    Introduction Shockable rhythms are rare in pediatric cardiac arrest and the results of defibrillation are uncertain. The objective of this study was to analyze the results of cardiopulmonary resuscitation that included defibrillation in children. Methods Forty-four out of 241 children (18.2%) who were resuscitated from inhospital or out-of-hospital cardiac arrest had been treated with manual defibrillation. Data were recorded according to the Utstein style. Outcome variables were a sustained return of spontaneous circulation (ROSC) and one-year survival. Characteristics of patients and of resuscitation were evaluated. Results Cardiac disease was the major cause of arrest in this group. Ventricular fibrillation (VF) or pulseless ventricular tachycardia (PVT) was the first documented electrocardiogram rhythm in 19 patients (43.2%). A shockable rhythm developed during resuscitation in 25 patients (56.8%). The first shock (dose, 2 J/kg) terminated VF or PVT in eight patients (18.1%). Seventeen children (38.6%) needed more than three shocks to solve VF or PVT. ROSC was achieved in 28 cases (63.6%) and it was sustained in 19 patients (43.2%). Only three patients (6.8%), however, survived at 1-year follow-up. Children with VF or PVT as the first documented rhythm had better ROSC, better initial survival and better final survival than children with subsequent VF or PVT. Children who survived were older than the finally dead patients. No significant differences in response rate were observed when first and second shocks were compared. The survival rate was higher in patients treated with a second shock dose of 2 J/kg than in those who received higher doses. Outcome was not related to the cause or the location of arrest. The survival rate was inversely related to the duration of cardiopulmonary resuscitation. Conclusion Defibrillation is necessary in 18% of children who suffer cardiac arrest. Termination of VF or PVT after the first defibrillation dose is achieved in a low

  6. [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

  7. 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

  8. 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.

  9. Echocardiographic assessment of cardiac disease

    NASA Technical Reports Server (NTRS)

    Popp, R. L.

    1976-01-01

    The physical principles and current applications of echocardiography in assessment of heart diseases are reviewed. Technical considerations and unresolved points relative to the use of echocardiography in various disease states are stressed. The discussion covers normal mitral valve motion, mitral stenosis, aortic regurgitation, atrial masses, mitral valve prolapse, and idiopathic hypertrophic subaortic stenosis. Other topics concern tricuspic valve abnormalities, aortic valve disease, pulmonic valve, pericardial effusion, intraventricular septal motion, and left ventricular function. The application of echocardiography to congenital heart disease diagnosis is discussed along with promising ultrasonic imaging systems. The utility of echocardiography in quantitative evaluation of cardiac disease is demonstrated.

  10. 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

  11. 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

  12. 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

  13. 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

  14. An unusual case of hematuria in a young female: renal artery embolism, mitral stenosis, and sinus rhythm.

    PubMed

    Kumar, Ashok; Kapoor, Aditya; Kumar, Sudeep

    2016-03-01

    Renal artery embolism (RAE) is an uncommon entity that is most often secondary to a cardiac source. Most reported cases have been in patients with underlying atrial fibrillation (AF), and occurrence of RAE, especially in patients with valvular heart disease, and sinus rhythm is very rare. We describe an unusual case of a young female who presented with sudden onset right flank pain, vomiting, anorexia, and hematuria, and was found to have thrombotic occlusion of the distal right renal artery. Although she denied any previous cardiac history, detailed cardiovascular examination revealed the presence of severe rheumatic mitral stenosis without any evidence of AF or left atrial clot. She was initially managed conservatively using low molecular weight heparin followed by oral anticoagulation with resolution of symptoms. A successful balloon mitral valvotomy was performed six weeks later. The patient is asymptomatic at her last follow-up of six months with preserved renal function. In symptomatic patients, clinicians need to consider the possibility of RAE even in patients of valvular heart disease with underlying sinus rhythm. Appropriate management of the underlying cardiac condition is imperative since embolism may be recurrent leading to compromise of renal function, if left untreated. PMID:26997399

  15. [Postmortem genetic testing in sudden cardiac death due to ion channelopathies].

    PubMed

    Guan, Da-wei; Zhao, Rui

    2010-04-01

    Sudden cardiac death accounts for majority of deaths in human. Evident cardiac lesions that may explain the cause of death can be detected in comprehensive postmortem investigation in most sudden cardiac death. However, no cardiac morphological abnormality is found in a considerable number of cases although the death is highly suspected from cardiac anomaly. With the advances in the modern molecular biology techniques, it has been discovered that many of these sudden deaths are caused by congenital ion channelopathies in myocardial cell, i.e., Brugada syndrome, long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, and short QT syndrome, etc. This article presents the molecular genetics, electrocardiographic abnormalities, clinical manifestations, and mechanisms leading to sudden cardiac death with emphasis on the role of postmortem genetic testing in certification of cause of death. It may provide helpful information in investigating sudden cardiac death due to ion channelopathies in medico-legal practice. PMID:20653139

  16. 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

  17. 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,…

  18. 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

  19. 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

  20. 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

  1. 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

  2. Myocardial bioenergetic abnormalities in experimental uremia

    PubMed Central

    Chesser, Alistair MS; Harwood, Steven M; Raftery, Martin J; Yaqoob, Muhammad M

    2016-01-01

    Purpose Cardiac bioenergetics are known to be abnormal in experimental uremia as exemplified by a reduced phosphocreatine (PCr)/adenosine triphosphate (ATP) ratio. However, the progression of these bioenergetic changes during the development of uremia still requires further study and was therefore investigated at baseline, 4 weeks and 8 weeks after partial nephrectomy (PNx). Methods A two-stage PNx uremia model in male Wistar rats was used to explore in vivo cardiac and skeletal muscles’ bioenergetic changes over time. High-energy phosphate nucleotides were determined by phosphorus-31 nuclear magnetic resonance (31P-NMR) and capillary zone electrophoresis. Results 31P-NMR spectroscopy revealed lower PCr/ATP ratios in PNx hearts compared to sham (SH)-operated animals 4 weeks after PNx (median values given ± SD, 0.64±0.16 PNx, 1.13±0.31 SH, P<0.02). However, 8 weeks after PNx, the same ratio was more comparable between the two groups (0.84±0.15 PNx, 1.04±0.44 SH, P= not significant), suggestive of an adaptive mechanism. When 8-week hearts were prestressed with dobutamine, the PCr/ATP ratio was again lower in the PNx group (1.08±0.36 PNx, 1.55±0.38 SH, P<0.02), indicating a reduced energy reserve during the progression of uremic heart disease. 31P-NMR data were confirmed by capillary zone electrophoresis, and the changes in myocardial bioenergetics were replicated in the skeletal muscle. Conclusion This study provides evidence of the changes that occur in myocardial energetics in experimental uremia and highlights how skeletal muscle bioenergetics mirror those found in the cardiac tissue and so might potentially serve as a practical surrogate tissue during clinical cardiac NMR investigations. PMID:27307758

  3. Imaging of cardiac sarcoidosis.

    PubMed

    Erthal, Fernanda; Juneau, Daniel; Lim, Siok P; Dwivedi, Girish; Nery, Pablo B; Birnie, David; Beanlands, Rob S

    2016-09-01

    Sarcoidosis is a multisystem inflammatory disease. Cardiac involvement is described in up to 50% of the cases. The disease spectrum is wide and cardiac manifestations ranges from being asymptomatic to heart failure, arrhythmias and sudden cardiac death. The diagnosis of cardiac sarcoidosis can be challenging due to its non-specific nature and the focal involvement of the heart. In this review, we discuss the utility of a stepwise approach with multimodality cardiac imaging in the diagnosis and management of CS. PMID:27225318

  4. 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

  5. The year in review of clinical cardiac electrophysiology.

    PubMed

    Marcus, Gregory M; Keung, Edmund; Scheinman, Melvin M

    2013-02-19

    This past year saw multiple important advances in the field clinical cardiac electrophysiology. Seminal articles describing new anticoagulant drugs for stroke prevention in atrial fibrillation were published. New results that raise questions regarding the safety of dronedarone and several new promising techniques in AF ablation were described. Important articles that refine our understanding of the risk of sudden death among Wolff-Parkinson-White patients were published. In the basic and translational sciences, the application of gene therapy to the study and potential treatment of arrhythmias was described, whereas genetic determinants important to the optimal treatment of inherited arrhythmia syndromes were further elucidated. Issues relevant to cardiac rhythm device therapy included investigations into the St. Jude Riata lead, new applications of device monitoring, predicting response to cardiac resynchronization therapy, and the use of pacemakers for vasovagal syncope. PMID:23312706

  6. High prevalence of incomplete right bundle branch block in facioscapulohumeral muscular dystrophy without cardiac symptoms

    PubMed Central

    van Dijk, Gaby Pons; van der Kooi, Elly; Behin, Anthony; Smeets, Joep; Timmermans, Janneke; van der Maarel, Silvère; Padberg, George; Voermans, Nicol; van Engelen, Baziel

    2014-01-01

    Summary The exact prevalence and nature of cardiac involvement in facioscapulohumeral muscular dystrophy (FSHD) is unknown. Nevertheless, the current opinion is that symptomatic cardiac disease is rare. We performed a cardiac screening [electrocardiogram (ECG) and echocardiography in the event of ECG abnormalities] in 75 genetically confirmed, ambulant FSHD patients without cardiac symptoms, with an eight-year follow-up of 57 patients, and compared the findings with results of previously performed cardiac screenings in the normal population. Baseline ECG demonstrated incomplete right bundle branch block (RBBB) in 33%, complete RBBB in 4%, and other minor abnormalities in 16%. Echocardiography showed no abnormalities. No significant changes were found after eight years of follow-up. Comparison with ECG abnormalities in the normal population showed a higher prevalence of incomplete RBBB (9.7 times higher) and of complete RBBB (4.8 times higher) in FSHD patients. This study in cardiac asymptomatic FSHD patients shows i) increased prevalence of incomplete RBBB in the absence of cardiomyopathy; ii) no progression of these abnormalities during eight years of follow-up. We conclude that FSHD patients without cardiac complaints do not need specific cardiac screening or surveillance. Furthermore, the increased prevalence of incomplete RBBB in the absence of cardiomyopathy suggests a selective involvement of the His-Purkinje system in FSHD. PMID:25473735

  7. 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.

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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.

  15. [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

  16. [Cardiac reserve in Parkinson's disease and exercise therapy].

    PubMed

    Hirayama, Masaaki; Nakamura, Tomohiko; Sobue, Gen

    2013-01-01

    The clinical feature of Parkinson's disease (PD) is not based on the identification of the extrapyramidal symptom such as bradykinesia, restinbg tremor, rigidity, but also other non-motor symptom (REM sleep disorder, autonomic dysfunction, hyposmia etc). According to the cardio-sympathetic dysfunction, it is well known abnormal MIBG and orthostatic hypotension finding was seen in early disease stage. Furthermore denervation supersensitivity using β1 stimulant correlates the severity of MIBG image, so that this abnormal cardiac function induces inadequate cardiac capacity for exercise. Inadequate cardiac capacity makes easy fatigability, which correlates the abnormal MIBG image and cardio-sympathetic damage. So it is difficult to prescribe a specific exercise program to meet individual PD patients needs. Music therapy and trunk exercise (for example Tai-Chi exercise) are better suited for PD patients. PMID:24291996

  17. 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…

  18. 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)

  19. 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...

  20. 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…

  1. 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

  2. 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.…

  3. 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.…

  4. 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…

  5. 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

  6. Inherited arrhythmias: The cardiac channelopathies.

    PubMed

    Behere, Shashank P; Weindling, Steven N

    2015-01-01

    Ion channels in the myocardial cellular membrane are responsible for allowing the cardiac action potential. Genetic abnormalities in these channels can predispose to life-threatening arrhythmias. We discuss the basic science of the cardiac action potential; outline the different clinical entities, including information regarding overlapping diagnoses, touching upon relevant genetics, new innovations in screening, diagnosis, risk stratification, and management. The special considerations of sudden unexplained death and sudden infant death syndrome are discussed. Scientists and clinicians continue to reconcile the rapidly growing body of knowledge regarding the molecular mechanisms and genetics while continuing to improve our understanding of the various clinical entities and their diagnosis and management in clinical setting. Two separate searches were run on the National Center for Biotechnology Information's website. The first using the term cardiac channelopathies was run on the PubMed database using filters for time (published in past 5 years) and age (birth-18 years), yielding 47 results. The second search using the medical subject headings (MeSH) database with the search terms "Long QT Syndrome" (MeSH) and "Short QT Syndrome" (MeSH) and "Brugada Syndrome" (MeSH) and "Catecholaminergic Polymorphic Ventricular Tachycardia" (MeSH), applying the same filters yielded 467 results. The abstracts of these articles were studied, and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles where further explored and read in full. PMID:26556967

  7. Inherited arrhythmias: The cardiac channelopathies

    PubMed Central

    Behere, Shashank P; Weindling, Steven N

    2015-01-01

    Ion channels in the myocardial cellular membrane are responsible for allowing the cardiac action potential. Genetic abnormalities in these channels can predispose to life-threatening arrhythmias. We discuss the basic science of the cardiac action potential; outline the different clinical entities, including information regarding overlapping diagnoses, touching upon relevant genetics, new innovations in screening, diagnosis, risk stratification, and management. The special considerations of sudden unexplained death and sudden infant death syndrome are discussed. Scientists and clinicians continue to reconcile the rapidly growing body of knowledge regarding the molecular mechanisms and genetics while continuing to improve our understanding of the various clinical entities and their diagnosis and management in clinical setting. Two separate searches were run on the National Center for Biotechnology Information's website. The first using the term cardiac channelopathies was run on the PubMed database using filters for time (published in past 5 years) and age (birth-18 years), yielding 47 results. The second search using the medical subject headings (MeSH) database with the search terms “Long QT Syndrome” (MeSH) and “Short QT Syndrome” (MeSH) and “Brugada Syndrome” (MeSH) and “Catecholaminergic Polymorphic Ventricular Tachycardia” (MeSH), applying the same filters yielded 467 results. The abstracts of these articles were studied, and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles where further explored and read in full. PMID:26556967

  8. 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

  9. Dobutamine "stress" test and latent cardiac susceptibility to inhaled diesel exhaust in normal and hypertensive rats**

    EPA Science Inventory

    Background -Exercise "stress" testing is a screening tool used to determine the amount of stress for which the heart can compensate before developing abnormal rhythm or ischemia, particularly in susceptible people. Although this approach has been used to assess risk in humans exp...

  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. Cardiac loop ECG recording: a new noninvasive diagnostic test in recurrent syncope.

    PubMed

    Cumbee, S R; Pryor, R E; Linzer, M

    1990-01-01

    The most crucial step in diagnosing syncope is determining whether or not an arrhythmia is the cause. A new recording device, the continuous cardiac loop ECG recorder, affords prolonged ambulatory monitoring and can capture the rhythm at the time of syncope. To determine the impact of cardiac loop ECG recorders in diagnosing syncope, we reviewed the records of the first 48 patients referred for cardiac loop recording because of unexplained syncope or presyncope. Previous cardiac studies were nondiagnostic in all patients. In 36% of these patients, loop recording definitively determined whether an arrhythmia was the cause of symptoms. Median duration of monitoring was 28 days, with an average charge of $180 per month. Cardiac loop ECG recording is a convenient, safe, inexpensive, and potentially highly effective means of diagnosing unexplained syncope. PMID:2300833

  16. Cardiac perception and cardiac control. A review.

    PubMed

    Carroll, D

    1977-12-01

    The evidence regarding specific cardiac perception and discrimination, and its relationship to voluntary cardiac control, is critically reviewed. Studies are considered in three sections, depending on the method used to assess cardiac perception: questionnaire assessment, discrimination procedures, and heartbeat tracking. The heartbeat tracking procedure would appear to suffer least from interpretative difficulties. Recommendations are made regarding the style of analysis used to assess heartbeat perception in such tracking tasks. PMID:348240

  17. 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

  18. 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.…

  19. Mapping cardiac surface mechanics with structured light imaging

    PubMed Central

    Laughner, Jacob I.; Zhang, Song; Li, Hao; Shao, Connie C.

    2012-01-01

    Cardiovascular disease often manifests as a combination of pathological electrical and structural heart remodeling. The relationship between mechanics and electrophysiology is crucial to our understanding of mechanisms of cardiac arrhythmias and the treatment of cardiac disease. While several technologies exist for describing whole heart electrophysiology, studies of cardiac mechanics are often limited to rhythmic patterns or small sections of tissue. Here, we present a comprehensive system based on ultrafast three-dimensional (3-D) structured light imaging to map surface dynamics of whole heart cardiac motion. Additionally, we introduce a novel nonrigid motion-tracking algorithm based on an isometry-maximizing optimization framework that forms correspondences between consecutive 3-D frames without the use of any fiducial markers. By combining our 3-D imaging system with nonrigid surface registration, we are able to measure cardiac surface mechanics at unprecedented spatial and temporal resolution. In conclusion, we demonstrate accurate cardiac deformation at over 200,000 surface points of a rabbit heart recorded at 200 frames/s and validate our results on highly contrasting heart motions during normal sinus rhythm, ventricular pacing, and ventricular fibrillation. PMID:22796539

  20. Hypothermia improves outcome from cardiac arrest.

    PubMed

    Bernard, S A

    2005-12-01

    Out-of-hospital cardiac arrest is common and patients who are initially resuscitated by ambulance officers and transported to hospital are usually admitted to the intensive care unit (ICU). In the past, the treatment in the ICU consisted of supportive care only, and most patients remained unconscious due to the severe anoxic neurological injury. It was this neurological injury rather than cardiac complications that caused the high rate of morbidity and mortality. However, in the early 1990's, a series of animal experiments demonstrated convincingly that mild hypothermia induced after return of spontaneous circulation and maintained for several hours dramatically reduced the severity of the anoxic neurological injury. In the mid-1990's, preliminary human studies suggested that mild hypothermia could be induced and maintained in post-cardiac arrest patients without an increase in the rate of cardiac or other complications. In the late 1990's, two prospective, randomised, controlled trials were conducted and the results confirmed the animal data that mild hypothermia induced after resuscitation and maintained for 12 - 24 hours dramatically improved neurological and overall outcomes. On the basis of these studies, mild hypothermia was endorsed in 2003 by the International Liaison Committee on Resuscitation as a recommended treatment for comatose patients with an initial cardiac rhythm of ventricular fibrillation. However, the application of this therapy into routine clinical critical care practice has been slow. The reasons for this are uncertain, but may relate to the relative complexity of the treatment, unfamiliarity with the pathophysiology of hypothermia, lack of clear protocols and/or uncertainty of benefit in particular patients. Therefore, recent research in this area has focused on the development of feasible, inexpensive techniques for the early, rapid induction of mild hypothermia after cardiac arrest. Currently, the most promising strategy is a rapid

  1. 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

  2. Causes of sudden unexpected cardiac death in the first two decades of life.

    PubMed

    Steinberger, J; Lucas, R V; Edwards, J E; Titus, J L

    1996-05-01

    Sudden, unexpected cardiac death in the age group 1 to 21 years usually is due to myocarditis, hypertrophic cardiomyopathy, aortic valvar stenosis, and coronary arterial abnormalities. The hearts of 70 patients <21 years of age who died suddenly were reviewed. Twenty patients were <1 year of age and 50 were 1 to 21 years old. The cardiac findings were compared with those in 68 age-matched controls with known cardiac disease who did not die suddenly. Significant cardiac abnormalities were present in 13 (65%) of the 20 infants; 10 (50%) had anomalies of the aortic origin of the coronary arteries. Among the 50 older patients, cardiac abnormalities were found in 40 (80%), among whom coronary arterial anomalies existed in 12 (24%). Anomalies of aortic origin more frequently involved the left main than the right coronary artery in both groups. PMID:8644651

  3. 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

  4. Cardiac manifestations in alcoholic liver disease.

    PubMed

    Milić, Sandra; Lulić, Davorka; Štimac, Davor; Ružić, Alen; Zaputović, Luka

    2016-04-01

    Alcoholic liver disease is the most prevalent cause of progressive liver disease in Europe. Alcoholic cirrhosis occurs in 8%-20% of cases of alcoholic liver disease. It has significant influence on cardiovascular system and haemodynamics through increased heart rate, cardiac output, decreased systemic vascular resistance, arterial pressure and plasma volume expansion. Cirrhotic cardiomyopathy is characterised by systolic and diastolic dysfunction and electrophysiological abnormalities, if no other underlying cardiac disease is present. It is often unmasked only during pharmacological or physiological stress, when compensatory mechanisms of the heart become insufficient to maintain adequate cardiac output. Low-to-moderate intake of alcohol can be cardioprotective. However, heavy drinking is associated with an increased risk of cardiovascular diseases, such as alcoholic cardiomyopathy, arterial hypertension, atrial arrhythmias as well as haemorrhagic and ischaemic stroke. Alcoholic cardiomyopathy is characterised by dilated left ventricle (LV), increased LV mass, normal or reduced LV wall thickness and systolic dysfunction. PMID:26850503

  5. 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.

  6. 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 ...

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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

  12. A cardiac electrical activity model based on a cellular automata system in comparison with neural network model.

    PubMed

    Khan, Muhammad Sadiq Ali; Yousuf, Sidrah

    2016-03-01

    Cardiac Electrical Activity is commonly distributed into three dimensions of Cardiac Tissue (Myocardium) and evolves with duration of time. The indicator of heart diseases can occur randomly at any time of a day. Heart rate, conduction and each electrical activity during cardiac cycle should be monitor non-invasively for the assessment of "Action Potential" (regular) and "Arrhythmia" (irregular) rhythms. Many heart diseases can easily be examined through Automata model like Cellular Automata concepts. This paper deals with the different states of cardiac rhythms using cellular automata with the comparison of neural network also provides fast and highly effective stimulation for the contraction of cardiac muscles on the Atria in the result of genesis of electrical spark or wave. The specific formulated model named as "States of automaton Proposed Model for CEA (Cardiac Electrical Activity)" by using Cellular Automata Methodology is commonly shows the three states of cardiac tissues conduction phenomena (i) Resting (Relax and Excitable state), (ii) ARP (Excited but Absolutely refractory Phase i.e. Excited but not able to excite neighboring cells) (iii) RRP (Excited but Relatively Refractory Phase i.e. Excited and able to excite neighboring cells). The result indicates most efficient modeling with few burden of computation and it is Action Potential during the pumping of blood in cardiac cycle. PMID:27087101

  13. 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

  14. 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

  15. Circadian clock and cardiac vulnerability: A time stamp on multi-scale neuroautonomic regulation

    NASA Astrophysics Data System (ADS)

    Ivanov, Plamen Ch.

    2005-03-01

    Cardiovascular vulnerability displays a 24-hour pattern with a peak between 9AM and 11AM. This daily pattern in cardiac risk is traditionally attributed to external factors including activity levels and sleep-wake cycles. However,influences from the endogenous circadian pacemaker independent from behaviors may also affect cardiac control. We investigate heartbeat dynamics in healthy subjects recorded throughout a 10-day protocol wherein the sleep/wake and behavior cycles are desynchronized from the endogenous circadian cycle,enabling assessment of circadian factors while controlling for behavior-related factors. We demonstrate that the scaling exponent characterizing temporal correlations in heartbeat dynamics over multiple time scales does exhibit a significant circadian rhythm with a sharp peak at the circadian phase corresponding to the period 9-11AM, and that this rhythm is independent from scheduled behaviors and mean heart rate. Our findings of strong circadian rhythms in the multi-scale heartbeat dynamics of healthy young subjects indicate that the underlying mechanism of cardiac regulation is strongly influenced by the endogenous circadian pacemaker. A similar circadian effect in vulnerable individuals with underlying cardiovascular disease would contribute to the morning peak of adverse cardiac events observed in epidemiological studies.

  16. Postoperative Atrial fibrillation in Patients undergoing Non-cardiac Non-thoracic Surgery: A Practical Approach for the Hospitalist

    PubMed Central

    Joshi, Kirti K.; Tiru, Mihaela; Chin, Thomas; Fox, Marshal T.; Stefan, Mihaela S.

    2016-01-01

    New postoperative atrial fibrillation (POAF) is the most common perioperative arrhythmia and its reported incidence ranges from 0.4%–26% in patients undergoing non-cardiac non-thoracic surgery. The incidence varies according to patient characteristics such as age, presence of structural heart disease and other co-morbidities, as well as the type of surgery performed. POAF occurs as a consequence of adrenergic stimulation, systemic inflammation, or autonomic activation in the intra or postoperative period (e.g. due to pain, hypotension, infection) in the setting of a susceptible myocardium and other predisposing factors (e.g. electrolyte abnormalities). POAF develops between day 1 and day 4 post-surgery and it is often considered a self-limited entity. Its acute management involves many of the same strategies used in non-surgical patients but the optimal long-term management is challenging because of the limited available evidence. Several studies have shown an association between occurrence of POAF and in-hospital morbidity, mortality, and length of stay. Although, traditionally, POAF was considered to have a generally favorable long-term prognosis, recent data have shown an association with an increased risk of stroke at one year after hospitalization. It is unknown, however, whether strategies to prevent POAF or for rate/rhythm control when it does occur, lead to a reduction in morbidity or mortality. This suggests the need for future studies to better understand the risks associated with POAF and to determine optimal strategies to minimize long-term thromboembolic risk. In this article, we summarize the current knowledge on epidemiology, pathophysiology, and short- and long-term management of POAF after non-cardiac non-thoracic surgery with the goal of providing a practical approach to managing these patients for the non-cardiologist clinician. PMID:26414594

  17. Cardiac conduction system

    MedlinePlus Videos and Cool Tools

    ... cardiac muscle cells in the walls of the heart that send signals to the heart muscle causing it to contract. The main components ... the cardiac conduction system’s electrical activity in the heart.

  18. What Is Cardiac Rehabilitation?

    MedlinePlus

    ANSWERS by heart Treatments + Tests What Is Cardiac Rehabilitation? A cardiac rehabilitation (rehab) program takes place in a hospital or ... special help in making lifestyle changes. During your rehabilitation program you’ll… • Have a medical evaluation to ...

  19. Sudden Cardiac Arrest

    MedlinePlus

    ... from American Heart Association Aneurysms and Dissections Angina Arrhythmia Bundle Branch Block Cardiomyopathy Carotid Artery Disease Chronic ... terms: SCA, sudden cardiac death (SCD), sudden death, arrhythmias, ... ventricular fibrillation, defibrillator, automatic cardiac defibrillator ( ...

  20. Cardiac Asystole Triggered by Temporal Lobe Epilepsy with Amygdala Enlargement.

    PubMed

    Arakawa, Junko; Nagai, Tomoo; Takasaki, Hiroshi; Sugano, Hidenori; Hamabe, Akira; Tahara, Mai; Mori, Hitoshi; Takase, Yoshiyuki; Gatate, Youdou; Togashi, Naohiko; Takiguchi, Shunichi; Nakaya, Kazuhiro; Ishigami, Norio; Tabata, Hirotsugu; Fukushima, Kouji; Katsushika, Shuichi

    2016-01-01

    A 25-year-old previously healthy man was hospitalized for syncope. While standing, he suddenly lost consciousness, followed by a generalized tonic clonic seizure. An electrocardiogram demonstrated asystole. No cardiac abnormalities were detected on the echocardiogram, cardiac magnetic resonance imaging (MRI), positron emission tomography, or a coronary angiogram. An electrophysiological study showed normal sinus node and atrioventricular node function. An electroencephalogram revealed small spike waves in the fronto-temporal region. Brain MRI demonstrated a left-sided amygdala enlargement. To the best of our knowledge, this is the first case of temporal lobe epilepsy with an amygdala enlargement that induced cardiac asystole. PMID:27250053

  1. 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.

  2. 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

  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. [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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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.

  13. [Sudden cardiac death in individuals with normal hearts: an update].

    PubMed

    González-Melchor, Laila; Villarreal-Molina, Teresa; Iturralde-Torres, Pedro; Medeiros-Domingo, Argelia

    2014-01-01

    Sudden death (SD) is a tragic event and a world-wide health problem. Every year, near 4-5 million people experience SD. SD is defined as the death occurred in 1h after the onset of symptoms in a person without previous signs of fatality. It can be named "recovered SD" when the case received medical attention, cardiac reanimation effective defibrillation or both, surviving the fatal arrhythmia. Cardiac channelopathies are a group of diseases characterized by abnormal ion channel function due to genetic mutations in ion channel genes, providing increased susceptibility to develop cardiac arrhythmias and SD. Usually the death occurs before 40 years of age and in the autopsy the heart is normal. In this review we discuss the main cardiac channelopathies involved in sudden cardiac death along with current management of cases and family members that have experienced such tragic event. PMID:25128006

  14. [Cardiac involvement in Churg-Strauss syndrome].

    PubMed

    Brucato, Antonio; Maestroni, Silvia; Masciocco, Gabriella; Ammirati, Enrico; Bonacina, Edgardo; Pedrotti, Patrizia

    2015-09-01

    Churg-Strauss syndrome, recently renamed eosinophilic granulomatosis with polyangiitis (EGPA), is a rare form of systemic vasculitis, characterized by disseminated necrotizing vasculitis with extravascular granulomas occurring among patients with asthma and tissue eosinophilia. EGPA is classified as a small and medium-sized vessel vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA) and the hypereosinophilic syndrome. Typical clinical features include asthma, sinusitis, transient pulmonary infiltrates and neuropathy. Blood eosinophils are often >1500/µl or more than 10% on the differential leukocyte count. Blood eosinophils should always be tested in unexplained cardiac disorders, and may normalize even after low doses of corticosteroids. ANCA are positive in 40-60% of cases, mainly anti-myeloperoxidase. Heart involvement occurs in approximately 15-60% of EGPA patients, especially those who are ANCA negative. Any cardiac structure can be involved, and patients present with myocarditis, heart failure, pericarditis, arrhythmia, coronary arteritis, valvulopathy, intracavitary cardiac thrombosis. Although cardiovascular involvement is usually an early manifestation, it can also occur later in the course of the disease. A significant proportion of patients with cardiac involvement is asymptomatic. In the absence of symptoms and major ECG abnormalities, cardiac involvement may be detected in nearly 40% of the patients. All patients with EGPA should be studied not only with a detailed history of cardiac symptoms and ECG, but also with echocardiography; if abnormalities are detected, a cardiac magnetic resonance study should be performed. Coronary angiography and endomyocardial biopsy should be reserved to selected cases. Heart involvement carries a poor prognosis and causes 50% of the deaths of these patients. It is often insidious and underestimated. Optimal therapy is therefore important and based on high-dose corticosteroids plus immunosuppressive

  15. A multimodal (MRI/ultrasound) cardiac phantom for imaging experiments

    NASA Astrophysics Data System (ADS)

    Tavakoli, Vahid; Kendrick, Michael; Shakeri, Mostafa; Alshaher, Motaz; Stoddard, Marcus F.; Amini, Amir

    2013-03-01

    A dynamic cardiac phantom can play a significant role in the evaluation and development of ultrasound and cardiac magnetic resonance (MR) motion tracking and registration methods. A four chamber multimodal cardiac phantom has been designed and built to simulate normal and pathologic hearts with different degrees of "infarction" and "scar tissues". In this set up, cardiac valves have been designed and modeled as well. The four-chamber structure can simulate the asymmetric ventricular, atrial and valve motions. Poly Vinyl Alcohol (PVA) is used as the principal material since it can simulate the shape, elasticity, and MR and ultrasound properties of the heart. The cardiac shape is simulated using a four-chamber mold made of polymer clay. An additional pathologic heart phantom containing stiff inclusions has been manufactured in order to simulate an infracted heart. The stiff inclusions are of different shapes and different degrees of elasticity and are able to simulate abnormal cardiac segments. The cardiac elasticity is adjusted based on freeze-thaw cycles of the PVA cryogel for normal and scarred regions. Ultrasound and MRI markers were inserted in the cardiac phantom as landmarks for validations. To the best of our knowledge, this is the first multimodal phantom that models a dynamic four-chamber human heart including the cardiac valve.

  16. Strategies for the prevention of sudden cardiac death during sports.

    PubMed

    Corrado, Domenico; Drezner, Jonathan; Basso, Cristina; Pelliccia, Antonio; Thiene, Gaetano

    2011-04-01

    Sudden cardiac death of a young athlete is the most tragic event in sports and devastates the family, the sports medicine team, and the local community. Such a fatality represents the first manifestation of cardiac disease in up to 80% of young athletes who remain asymptomatic before sudden cardiac arrest occurs; this explains the limited power of screening modalities based solely on history and physical examination. The long-running Italian experience showed that electrocardiogram (ECG) screening definitively improves the sensitivity of pre-participation evaluation for heart diseases and substantially reduces the risk of death in the athletic field (primary prevention). However, some cardiac conditions, such as coronary artery diseases, present no abnormalities on 12-lead ECG. Moreover, cardiac arrest due to non-penetrating chest injury (commotio cordis) cannot be prevented by screening. This justifies the efforts for implementing programmes of early external defibrillation of unpredictable arrhythmic cardiac arrest. This article reviews the epidemiology of sudden cardiac arrest in the athlete in terms of incidence, sport-related risk, underlying causes, and the currently available prevention programmes such as pre-participation screening and early external defibrillation by using automated external defibrillators. The best strategy is to combine synergistically primary prevention of sudden cardiac death by pre-participation identification of athletes affected by at-risk cardiomyopathies and secondary prevention with back-up defibrillation of unpredictable sudden cardiac arrest on the athletic field. PMID:21567995

  17. Circadian rhythms in human performance and mood under constant conditions

    NASA Technical Reports Server (NTRS)

    Monk, T. H.; Buysse, D. J.; Reynolds, C. F. 3rd; Berga, S. L.; Jarrett, D. B.; Begley, A. E.; Kupfer, D. J.

    1997-01-01

    This study explored the relationship between circadian performance rhythms and rhythms in rectal temperature, plasma cortisol, plasma melatonin, subjective alertness and well-being. Seventeen healthy young adults were studied under 36 h of 'unmasking' conditions (constant wakeful bedrest, temporal isolation, homogenized 'meals') during which rectal temperatures were measured every minute, and plasma cortisol and plasma melatonin measured every 20 min. Hourly subjective ratings of global vigour (alertness) and affect (well-being) were obtained followed by one of two performance batteries. On odd-numbered hours performance (speed and accuracy) of serial search, verbal reasoning and manual dexterity tasks was assessed. On even-numbered hours, performance (% hits, response speed) was measured at a 25-30 min visual vigilance task. Performance of all tasks (except search accuracy) showed a significant time of day variation usually with a nocturnal trough close to the trough in rectal temperature. Performance rhythms appeared not to reliably differ with working memory load. Within subjects, predominantly positive correlations emerged between good performance and higher temperatures and better subjective alertness; predominantly negative correlations between good performance and higher plasma levels of cortisol and melatonin. Temperature and cortisol rhythms correlated with slightly more performance measures (5/7) than did melatonin rhythms (4/7). Global vigour correlated about as well with performance (5/7) as did temperature, and considerably better than global affect (1/7). In conclusion: (1) between-task heterogeneity in circadian performance rhythms appeared to be absent when the sleep/wake cycle was suspended; (2) temperature (positively), cortisol and melatonin (negatively) appeared equally good as circadian correlates of performance, and (3) subjective alertness correlated with performance rhythms as well as (but not better than) body temperature, suggesting that

  18. Cardiac Biomarkers: a Focus on Cardiac Regeneration

    PubMed Central

    Forough, Reza; Scarcello, Catherine; Perkins, Matthew

    2011-01-01

    Historically, biomarkers have been used in two major ways to maintain and improve better health status: first, for diagnostic purposes, and second, as specific targets to treat various diseases. A new era in treatment and even cure for the some diseases using reprograming of somatic cells is about to be born. In this approach, scientists are successfully taking human skin cells (previously considered terminally-differentiated cells) and re-programming them into functional cardiac myocytes and other cell types in vitro. A cell reprograming approach for treatment of cardiovascular diseases will revolutionize the field of medicine and significantly expand the human lifetime. Availability of a comprehensive catalogue for cardiac biomarkers is necessary for developing cell reprograming modalities to treat cardiac diseases, as well as for determining the progress of reprogrammed cells as they become cardiac cells. In this review, we present a comprehensive survey of the cardiac biomarkers currently known. PMID:23074366

  19. Circadian rhythms from multiple oscillators: lessons from diverse organisms.

    PubMed

    Bell-Pedersen, Deborah; Cassone, Vincent M; Earnest, David J; Golden, Susan S; Hardin, Paul E; Thomas, Terry L; Zoran, Mark J

    2005-07-01

    The organization of biological activities into daily cycles is universal in organisms as diverse as cyanobacteria, fungi, algae, plants, flies, birds and man. Comparisons of circadian clocks in unicellular and multicellular organisms using molecular genetics and genomics have provided new insights into the mechanisms and complexity of clock systems. Whereas unicellular organisms require stand-alone clocks that can generate 24-hour rhythms for diverse processes, organisms with differentiated tissues can partition clock function to generate and coordinate different rhythms. In both cases, the temporal coordination of a multi-oscillator system is essential for producing robust circadian rhythms of gene expression and biological activity. PMID:15951747

  20. 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.

  1. Attraction and social coordination: mutual entrainment of vocal activity rhythms.

    PubMed

    McGarva, Andrew R; Warner, Rebecca M

    2003-05-01

    To investigate factors that affect the mutual entrainment of vocal activity rhythms, female general psychology students paired according to attitude similarity questionnaires engaged in 40-minute introductory conversations. Fourier analyses performed on speakers' on-off vocal activity demonstrated periodic oscillations in talkativeness. Although some dyads coordinated their vocal activity rhythms, speech accommodation was not predicted by attitude similarity or attraction and did not affect ratings of conversation quality. These rhythms of dialogue appear resistant to change, their behavioral momentum rooted perhaps in an underlying chronobiology. PMID:12845943

  2. Stormy Course of a Huge Submitral Aneurysm Causing Low Cardiac Output State

    PubMed Central

    Gokhroo, Rajendra Kumar; Kishor, Kamal; Ranwa, Bhanwar

    2016-01-01

    Submitral aneurysm is a rare structural abnormality of congenital or acquired aetiology. Most reported cases are from Africa. Unless promptly treated surgically this condition is invariably fatal. We report a case of a young Indian male who presented with dyspnea of recent onset, diagnosed to have a massive submitral aneurysm causing low cardiac output and compression of cardiac structures. PMID:27081448

  3. Newer methods of cardiac output monitoring

    PubMed Central

    Mehta, Yatin; Arora, Dheeraj

    2014-01-01

    Cardiac output (CO) is the volume of blood ejected by each ventricle per minute and is the product of stroke volume and heart rate. CO can thus be manipulated by alteration in heart rate or rhythm, preload, contractility and afterload. Moreover it gives important information about tissue perfusion and oxygen delivery. CO can be measured by various methods and thermodilution method using pulmonary artery catheter (PAC) is till date considered as gold standard method. Complications associated with PAC led to development of newer methods which are minimally or non-invasive. Newer methods fulfil other properties like continuous and reproducible reading, cost effective, reliable during various physiological states and have fast response time. These methods are validated against the gold standard with good level agreement. In this review we have discussed various newer methods of CO monitoring and their effectiveness in clinical use. PMID:25276302

  4. Quadricuspid aortic valve by cardiac magnetic resonance imaging: a case report and review of the literature.

    PubMed

    Khan, Shamruz Khan Akerem; Tamin, Syahidah Syed; Araoz, Philip A

    2011-01-01

    Quadricuspid aortic valve (QAV) is a rare congenital cardiac entity. The recognition of QAV has clinical significance as it causes aortic valve dysfunction, commonly aortic regurgitation, and is often associated with other congenital cardiac abnormalities. We showed the important role played by cardiac magnetic resonance imaging in detecting QAV and review the available literature to explain its incidence, diagnosis, classifications, embryology, correlation between morphology of the QAV and its function, associated conditions, and management. PMID:21926862

  5. 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

  6. Eye movement abnormalities.

    PubMed

    Moncayo, Jorge; Bogousslavsky, Julien

    2012-01-01

    Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem. PMID:22377853

  7. The Neural Crest in Cardiac Congenital Anomalies

    PubMed Central

    Keyte, Anna; Hutson, Mary Redmond

    2012-01-01

    This review discusses the function of neural crest as they relate to cardiovascular defects. The cardiac neural crest cells are a subpopulation of cranial neural crest discovered nearly 30 years ago by ablation of premigratory neural crest. The cardiac neural crest cells are necessary for normal cardiovascular development. We begin with a description of the crest cells in normal development, including their function in remodeling the pharyngeal arch arteries, outflow tract septation, valvulogenesis, and development of the cardiac conduction system. The cells are also responsible for modulating signaling in the caudal pharynx, including the second heart field. Many of the molecular pathways that are known to influence specification, migration, patterning and final targeting of the cardiac neural crest cells are reviewed. The cardiac neural crest cells play a critical role in the pathogenesis of various human cardiocraniofacial syndromes such as DiGeorge, Velocardiofacial, CHARGE, Fetal Alcohol, Alagille, LEOPARD, and Noonan syndromes, as well as Retinoic Acid Embryopathy. The loss of neural crest cells or their dysfunction may not always directly cause abnormal cardiovascular development, but are involved secondarily because crest cells represent a major component in the complex tissue interactions in the head, pharynx and outflow tract. Thus many of the human syndromes linking defects in the heart, face and brain can be better understood when considered within the context of a single cardiocraniofacial developmental module with the neural crest being a key cell type that interconnects the regions. PMID:22595346

  8. Exercise-related sudden cardiac arrest in London: incidence, survival and bystander response

    PubMed Central

    Edwards, Melanie J; Fothergill, Rachael T

    2015-01-01

    Objective The study aimed to (1) establish the incidence of exercise-related sudden cardiac arrest (SCA) in London, (2) investigate survival from exercise-related SCA and (3) examine factors related to survival. Method This retrospective observational study examined 2 years’ data from the London Ambulance Service (LAS) cardiac arrest registry for patients in whom resuscitation was attempted following an out-of-hospital cardiac arrest (OHCA), a cardiac cause was presumed and the arrest occurred during or within 1 h of exercise. Results The incidence of exercise-related SCA in London was estimated to be 0.6 per 100 000 person-years which equated to 0.5% of all OHCA, and 1.5% of all OHCA with presumed cardiac aetiology and resuscitation attempted. The majority of cases were male and the incidence increased from age 40 years. Just under one-third of patients survived to hospital discharge. Survival in the Utstein comparator group (cases with presumed cardiac aetiology, resuscitation attempted, bystander witnessed and a presenting cardiac rhythm of ventricular fibrillation or tachycardia) was higher at 42%. Survival was significantly associated with initial cardiac rhythm (χ2=17.5, df=2, p<0.001) and bystander defibrillation (Fisher's exact test, p<0.05). Conclusions Incidence of exercise-related SCA in the general population in London is rare. Survival following exercise-related SCA was considerably higher than survival for all OHCA with presumed cardiac aetiology and resuscitation attempted attended by the LAS during the same period. The major limitation of the study is the likely under identification of cases of exercise-related SCA. PMID:26468401

  9. Menstrual changes in sleep, rectal temperature and melatonin rhythms in a subject with premenstrual syndrome.

    PubMed

    Shinohara, K; Uchiyama, M; Okawa, M; Saito, K; Kawaguchi, M; Funabashi, T; Kimura, F

    2000-03-10

    We studied a sighted woman with premenstrual syndrome who showed menstrual changes in circadian rhythms. She showed alternative phase shifts in the sleep rhythm in the menstrual cycle: progressive phase advances in the follicular phase and phase delays in the luteal phase. Rectal temperature rhythm also showed similar menstrual changes, but the phase advance and delay started a few days earlier than changes in sleep-wake rhythm so that the two rhythms were dissociated around ovulation and menstruation. These results suggest that her circadian rhythms in sleep and temperature are under the control of ovarian steroid hormones and that these two rhythms have different sensitivity to the hormones. PMID:10704767

  10. Chronic unpredictable stress induces a reversible change of PER2 rhythm in the suprachiasmatic nucleus.

    PubMed

    Jiang, Wen-Gao; Li, Su-Xia; Zhou, Shuang-Jiang; Sun, Yan; Shi, Jie; Lu, Lin

    2011-07-01

    Many clinical studies have shown that circadian rhythm abnormalities are strongly associated with major depression. The master clock of the circadian system in mammals is located in the suprachiasmatic nucleus (SCN) within the anterior hypothalamus, where Per1 and Per2 are essential core components of circadian rhythm oscillation. Chronic unpredictable stress (CUS) is a reliable animal model of depression with good face, predictive, and constructive validity. In the present study, we investigated the effects of CUS on the circadian expression of PER1 and PER2 in the SCN. We found that CUS led to depressive-like behavior and reduced the amplitude of PER2 oscillation in the SCN, which were blocked by 3 weeks of desipramine (DMI) treatment. 2 weeks after termination of CUS, the decreased peak of PER2 expression returned to control levels, whereas depressive-like behavior remained unchanged. Our findings suggest that the dampened amplitude of PER2 expression in the SCN may participate in the development of depressive-like behavior induced by CUS but is unlikely involved in the long-lasting effects of CUS on depressive-like behavior. PMID:21621196

  11. Interval analysis of interictal EEG: pathology of the alpha rhythm in focal epilepsy

    NASA Astrophysics Data System (ADS)

    Pyrzowski, Jan; Siemiński, Mariusz; Sarnowska, Anna; Jedrzejczak, Joanna; Nyka, Walenty M.

    2015-11-01

    The contemporary use of interictal scalp electroencephalography (EEG) in the context of focal epilepsy workup relies on the visual identification of interictal epileptiform discharges. The high-specificity performance of this marker comes, however, at a cost of only moderate sensitivity. Zero-crossing interval analysis is an alternative to Fourier analysis for the assessment of the rhythmic component of EEG signals. We applied this method to standard EEG recordings of 78 patients divided into 4 subgroups: temporal lobe epilepsy (TLE), frontal lobe epilepsy (FLE), psychogenic nonepileptic seizures (PNES) and nonepileptic patients with headache. Interval-analysis based markers were capable of effectively discriminating patients with epilepsy from those in control subgroups (AUC~0.8) with diagnostic sensitivity potentially exceeding that of visual analysis. The identified putative epilepsy-specific markers were sensitive to the properties of the alpha rhythm and displayed weak or non-significant dependences on the number of antiepileptic drugs (AEDs) taken by the patients. Significant AED-related effects were concentrated in the theta interval range and an associated marker allowed for identification of patients on AED polytherapy (AUC~0.9). Interval analysis may thus, in perspective, increase the diagnostic yield of interictal scalp EEG. Our findings point to the possible existence of alpha rhythm abnormalities in patients with epilepsy.

  12. Circadian rhythms of temperature and activity in obese and lean Zucker rats

    NASA Technical Reports Server (NTRS)

    Murakami, D. M.; Horwitz, B. A.; Fuller, C. A.

    1995-01-01

    The circadian timing system is important in the regulation of feeding and metabolism, both of which are aberrant in the obese Zucker rat. This study tested the hypothesis that these abnormalities involve a deficit in circadian regulation by examining the circadian rhythms of body temperature and activity in lean and obese Zucker rats exposed to normal light-dark cycles, constant light, and constant dark. Significant deficits in both daily mean and circadian amplitude of temperature and activity were found in obese Zucker female rats relative to lean controls in all lighting conditions. However, the circadian period of obese Zucker rats did not exhibit differences relative to lean controls in either of the constant lighting conditions. These results indicate that although the circadian regulation of temperature and activity in obese Zucker female rats is in fact depressed, obese rats do exhibit normal entrainment and pacemaker functions in the circadian timing system. The results suggest a deficit in the process that generates the amplitude of the circadian rhythm.

  13. Cardiac gated ventilation

    SciTech Connect

    Hanson, C.W. III; Hoffman, E.A.

    1995-12-31

    There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. The authors evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50 msec scan aperture. Multi slice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart.

  14. Cardiac gated ventilation

    NASA Astrophysics Data System (ADS)

    Hanson, C. William, III; Hoffman, Eric A.

    1995-05-01

    There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. We evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50msec scan aperture. Multislice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. We observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a nonfailing model of the heart.

  15. Speech rhythm sensitivity and musical aptitude: ERPs and individual differences.

    PubMed

    Magne, Cyrille; Jordan, Deanna K; Gordon, Reyna L

    2016-02-01

    This study investigated the electrophysiological markers of rhythmic expectancy during speech perception. In addition, given the large literature showing overlaps between cognitive and neural resources recruited for language and music, we considered a relation between musical aptitude and individual differences in speech rhythm sensitivity. Twenty adults were administered a standardized assessment of musical aptitude, and EEG was recorded as participants listened to sequences of four bisyllabic words for which the stress pattern of the final word either matched or mismatched the stress pattern of the preceding words. Words with unexpected stress patterns elicited an increased fronto-central mid-latency negativity. In addition, rhythm aptitude significantly correlated with the size of the negative effect elicited by unexpected iambic words, the least common type of stress pattern in English. The present results suggest shared neurocognitive resources for speech rhythm and musical rhythm. PMID:26828758

  16. Rhythm: A Psycho-Philosophical Perspective on Black Behavior.

    ERIC Educational Resources Information Center

    Toldson, Ivory L.; Pasteur, Alfred B.

    1982-01-01

    Discusses rhythm as a fundamental element in human behavior. Suggests that the unity of cognitive, affective, and psychomotor functioning, most vividly seen in Black expressive forms, must be studied to more fully understand Black behavior and learning styles. (RC)

  17. Social Rhythm Therapies for Mood Disorders: an Update.

    PubMed

    Haynes, Patricia L; Gengler, Devan; Kelly, Monica

    2016-08-01

    Social rhythms are patterns of habitual daily behaviors that may impact the timing of the circadian system directly or indirectly through light exposure. According to the social rhythm hypothesis of depression, depressed individuals possess a vulnerability in the circadian timing system that inhibits natural recovery after disrupting life events. Social rhythm therapies (SRTs) support the implementation of regular, daily patterns of activity in order to facilitate recovery of circadian biological processes and also to improve mood. The majority of SRT research has examined interpersonal and social rhythm therapy (IPSRT) for bipolar disorder. Recent studies have examined IPSRT in inpatient settings, using alternative modes of delivery (group, combined individual and group, internet-based applications) and with brief timeframes. New forms of SRTs are developing that target mood in individuals who have experienced specific types of stressful life events. This manuscript reviews the theoretical and biological bases of SRTs and current literature on SRT outcomes. PMID:27338753

  18. [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

  19. Preliminary characterization of persisting circadian rhythms during space flight

    NASA Technical Reports Server (NTRS)

    Sultzman, F. M.

    1984-01-01

    In order to evaluate the function of the circadian timing system in space, the circadian rhythm of conidiation of the fungus Neurospora crassa was monitored in constant darkness on the STS 9 flight of the Space Shuttle Columbia. During the first 7 days of spaceflight many tubes showed a marked reduction in the apparent amplitude of the conidiation rhythm, and some cultures appeared arrhythmic. There was more variability in the growth rate and circadian rhythms of individual cultures in space than is usually seen on earth. The results of this experiment indicate that while the circadian rhythm of Neurospora conidiation can persist outside of the earth's environment, either the timekeeping process or its expression is altered in space.

  20. 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 ...