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Dikecligil Gülce N - - 2010
Heart rate variability (HRV) measures homeostatic regulation of the autonomic nervous system in response to perturbation and has been previously shown to quantify risk for cardiac events. Despite known interactions among stress vulnerability, psychiatric illness, and cardiac health, however, this is the first study to our knowledge to compare directly ...
Magrans R - - 2010
We assess autonomic nervous system response during prolonged percutaneous transluminal coronary angioplasty (PTCA) using heart rate variability analysis with multifractal indices. These indices are used to evaluate the effects of the PTCA procedures at different arteries and locations. A total of 55 patients from the Staff3 database, with no prior ...
Saburkina Inga - - 2010
Sheep are routinely used in experimental cardiac electrophysiology and surgery. The purpose of this study was to (1) ascertain the topography and architecture of the ovine epicardial neural plexus (ENP), (2) determine the relationships of ENP with vagal and sympathetic cardiac nerves and ganglia, and (3) evaluate gross anatomic differences ...
Lujan Heidi L - - 2010
The Cardiac Arrhythmia Suppression Trial demonstrated that antiarrhythmic drugs not only fail to prevent sudden cardiac death, but actually increase overall mortality. These findings have been confirmed in additional trials. The "proarrhythmic" effects of most currently available antiarrhythmic drugs makes it essential that we investigate novel strategies for the prevention ...
Goya-Esteban Rebeca - - 2010
Heart rate variability (HRV) markers have been widely used to characterize the autonomous regulation state of the heart from 24-h Holter monitoring, but long-term evolution of HRV indexes is mostly unknown. A dataset of 7-day Holter recordings of 22 patients with congestive heart failure was studied. A rhythmometric procedure was ...
Jones David E J DE Institute of Cellular Medicine, Newcastle Univ., - - 2010
Cardiovascular system dysregulation in the form of autonomic dysfunction is common at all stages of the disease process in the autoimmune liver disease primary biliary cirrhosis (PBC) and associates with the symptom of fatigue. The mechanisms underpinning autonomic dysfunction in PBC are, however, at present unclear. In this study we ...
Lara Aline - - 2010
Overwhelming evidence supports the importance of the sympathetic nervous system in heart failure. In contrast, much less is known about the role of failing cholinergic neurotransmission in cardiac disease. By using a unique genetically modified mouse line with reduced expression of the vesicular acetylcholine transporter (VAChT) and consequently decreased release ...
Fazio Giovanni - - 2010
BACKGROUND: It is well-known that a reduction of the cardiac frequency variability, measurable with the Heart Rate Variability (HRV) system, is an indirect expression of the sympathetic-autonomic tone. Another index, Heart Rate Turbulence (HRT), has been recently suggested as a possible unit of measurement for the sympathetic-autonomic tone: this system ...
Sevcencu Cristian - - 2010
Studies with heart rate variability have revealed interictal autonomic alterations in patients with epilepsy. In addition, epilepsy is frequently associated with ictal tachycardia or bradycardia, which sometimes precedes the onset of seizures. Ictal tachycardia is sometimes associated with electrocardiography (ECG) morphologic changes and ictal bradycardia often progresses to asystole. Such ...
Smith Michael L - - 2010
BACKGROUND: Sudden cardiac death is usually caused by ventricular arrhythmias and in many cases, is preceded by frequent ventricular ectopy. It is known that ectopic beats cause transient increases in sympathetic nerve activity (SNA). OBJECTIVE: Because high SNA is known to be arrhythmogenic, we hypothesized that high rates of ectopy ...
Kanazawa Hideaki - - 2010
Although several cytokines and neurotrophic factors induce sympathetic neurons to transdifferentiate into cholinergic neurons in vitro, the physiological and pathophysiological roles of this remain unknown. During congestive heart failure (CHF), sympathetic neural tone is upregulated, but there is a paradoxical reduction in norepinephrine synthesis and reuptake in the cardiac sympathetic ...
Levick Scott P SP Cell Biology and Anatomy, School of Medicine, University of South Carolina, Columbia, SC 29208, - - 2010
Chronic activation of the sympathetic nervous system is a key component of cardiac hypertrophy and fibrosis. However, previous studies have provided evidence that also implicate inflammatory cells, including mast cells (MCs), in the development of cardiac fibrosis. The current study investigated the potential interaction of cardiac MCs with the sympathetic ...
Hill Labarron K - - 2010
Conceptualizations of parasympathetic and sympathetic activity of the autonomic nervous system as representing a bi-dimensional autonomic space have driven recent discussions surrounding the degree of respective and interactive influence of each branch on visceral organs (e.g. heart). An important consideration of autonomic influences on cardiac function is the presence of ...
Drakos Stavros G - - 2010
OBJECTIVES: The purpose of this study was to analyze the effects of left ventricular assist devices (LVADs) on myocardial sympathetic innervation of the failing heart. BACKGROUND: Ventricular unloading by LVADs seems to cause reverse remodeling of the failing heart, but little is known about the sympathetic nerve activity during long-term ...
Christensen J H - - 2010
Studies suggest that marine n-3 polyunsaturated fatty acids (PUFA) offer some protection against sudden cardiac death (SCD). The autonomic nervous system is involved in the pathogenesis of SCD and due to the fact that n-3 PUFA is abundant in the brain and other nervous tissue it is likely that n-3 ...
Turker Yasin - - 2010
BACKGROUND: Coronary artery ectasia (CAE) is characterized by an abnormal dilatation of the coronary arteries, which is a variant of coronary artery disease (CAD). Increased sympathetic activity or decreased vagal modulation of cardiac function assessed by heart rate variability (HRV) analysis has been associated with an increased risk of coronary ...
I?ler Y - - 2010
In this study, the effects of heart rate (HR) normalization in the analysis of the heart rate variability (HRV) were investigated to distinguish 29 patients with congestive heart failure from 54 healthy subjects in the control group. In the analysis performed, the best accuracy performances of optimal combination of standard ...
Schneider Alexandra - - 2010
Exposure to ambient particles has been shown to be responsible for cardiovascular effects, especially in elderly with cardiovascular disease. The study assessed the association between deceleration capacity (DC) as well as heart rate variability (HRV) and ambient particulate matter (PM) in patients with coronary artery disease (CAD). A prospective study ...
Puchades Ramón R Unidad de Hipertensión, Servicio de Medicina Interna, Hospital Universitario de La Princesa, Red RECAVA, Madrid, - - 2010
The aims of this study were to investigate left ventricular morphology in a sample of elderly Spanish individuals and to assess differences between hypertensives and normotensives. Data were obtained from a subsample (N=242) of participants in the EPICARDIAN study who live in the Lista district of Madrid: they included 191 ...
Leonarduzzi Roberto Fabio RF Lab. Signals and Nonlinear Dynamics, Faculty of Engineering, Universidad Nacional de Entre Ríos, Argentina. - - 2010
Heart rate variability is a non invasive and indirect measure of the autonomic control of the heart. Therefore, alterations to this control system caused by myocardial ischaemia are reflected in changes in the complex and irregular fluctuations of this signal. Multifractal analysis is a well suited tool for the analysis ...
Goldie Jessica J Faculty of Health Sciences, University of Ontario Institute of Technology, 2000 Simcoe St. N., Oshawa, L1H 7K4 Canada. - - 2010
Introduction. Electrocardiography (ECG) can be used to collect heart rate data which in turn can be used to measure heart rate variability (HRV). The sympathetic and parasympathetic nervous systems have the ability to affect this variability, which can ultimately affect arousal levels.
D'Addio Gianni G S. Maugeri Foundation, Bioengeneering Dpt. of Rehabilitation Institute of Telese, via Bagni Vecchi 82037 Telese Terme, (BN) Italy. - - 2010
Cardiovascular oscillations following spontaneous ventricular premature complexes (VPC) are characterized by a short-term heart rate fluctuation known as heart rate turbulence (HRT) described by the so-called turbulence onset (TO) and slope (TS). Despite a recent written consensus on the standard of HRT measurement, reproducibility data are lacking. Aim of the ...
Di Rienzo Marco M Dept. of Biomedical Technology, "Santa Maria Nascente" Research Hospital, Fondazione Don Carlo Gnocchi, 20148 Milan, Italy. - - 2010
The Push-Pull Effect (PPE) is a physiological phenomenon defined as a reduction of +Gz tolerance induced by a previous exposure to a -Gz acceleration, that may lead to loss of consciousness. Aim of this study was to evaluate, for the first time, the cardiac rhythm changes associated with PPE during ...
Akutsu Yasushi - - 2010
We evaluate the systemic right ventricle (SRV) failure of congenitally corrected transposition of the great arteries using the scintigraphic studies in a case with 32-year-old male who improved the heart failure by the use of beta-adrenergic blockers. The myocardial perfusion sympathetic nervous system activity mismatch with preserved coronary flow and ...
Mueller E M - - 2010
Cortical efferences to the heart are important for cardiovascular health, psychopathology, emotion regulation and other dimensions of human functioning. Although researchers have already begun to outline the underlying neuroanatomy, the timing of neurovisceral communication in humans is difficult to study non-invasively. A possible coupling between the brain and the heart ...
Khandoker Ahsan H - - 2010
Early sub-clinical assessment of severity of cardiac autonomic neuropathy (CAN) and intervention are of prime importance for risk stratification and early treatment in preventing sudden death due to silent myocardial infarction. The Ewing battery is currently the diagnostic tool of choice but is unable to detect sub-clinical disease and requires ...
Esler Murray - - 2010
Sympathetic nervous system responses typically are regionally differentiated, with activation in one outflow sometimes accompanying no change or sympathetic inhibition in another. Regional sympathetic activity is best studied in humans by recording from postganglionic sympathetic efferents (multiunit or single fiber recording) and by isotope dilution-derived measurement of organ-specific norepinephrine release ...
Huang Chien-Hua - - 2010
Epidemiological studies show an association between particulate matter exposure and acute heart failure. However, underlying mechanisms remain unclear. In this study, we investigated acute cardiac hemodynamic effects and related mechanisms after 1 day exposure to diesel exhaust particles (DEPs). Male Sprague-Dawley rats were randomized and instilled with 250 microg (low ...
Fu Liang-Wu - - 2010
Myocardial ischemia is a complex process leading to the simultaneous release of a number of mediators, including thromboxane A(2) (TxA(2)) and bradykinin (BK), that activate cardiac spinal afferents. The present study tested the hypothesis that TxA(2) and BK reciprocally interact to excite ischemically sensitive cardiac afferents. Nerve activity of single ...
Soliman Elsayed Z - - 2010
AIMS: High resting heart rate (HR) has been associated with sudden cardiac death (SCD). This association is not fully explained by the reported association between HR with coronary heart disease (CHD) or left ventricular systolic dysfunction, the major pathological substrates for SCD. Ventricular arrhythmia is the most common antecedent event ...
Valencia Jose F - - 2009
This work has proposed a methodology based on the concept of entropy rates to study the complexity of the short-term heart-rate variability (HRV) for improving risk stratification to predict sudden cardiac death (SCD) of patients with established ischemic-dilated cardiomyopathy (IDC). The short-term HRV was analyzed during daytime and nighttime by ...
Parrish Diana C DC Department of Physiology and Pharmacology, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, - - 2010
Myocardial infarction causes a heterogeneity of noradrenergic transmission that contributes to the development of ventricular arrhythmias and sudden cardiac death. Ischaemia-induced alterations in sympathetic transmission include regional variations in cardiac noradrenaline (NA) and in tyrosine hydroxylase, the rate-limiting enzyme in NA synthesis. Inflammatory cytokines that act through gp130 are elevated ...
Maestri Roberto - - 2010
Despite a well-established prognostic value in cardiac patients, HRV (heart rate variability) indexes have been used little in the clinical setting. Poor reliability of the measurements might be a possible explanation for this. In the present study, we assessed the reliability of short-term HRV indexes in post-MI (myocardial infarction) patients. ...
Karmakar C K - - 2009
The asymmetry in heart rate variability is a visibly obvious phenomenon in the Poincaré plot of normal sinus rhythm. It shows the unevenness in the distribution of points above and below the line of identity, which indicates instantaneous changes in the beat to beat heart rate. The major limitation of ...
Ghebremedhin Estifanos - - 2009
Clinical and autopsy studies have consistently reported cardiac sympathetic dysfunction in the left ventricular wall in patients with Parkinson's disease (PD). Whether the nerve fibers of the cardiac conduction system or the atrial walls are equally affected in this disease process has not yet been well documented. Therefore, the aim ...
Chen Hung Yi - - 2009
BACKGROUND: Heart rate turbulence (HRT) has recently been introduced as a noninvasive tool for studying autonomic dysfunction. It presented short time fluctuation of sinus cycle length following single ventricular premature contraction (VPC). However, HRT parameters may be influenced by different factors. This study aimed to evaluate the possible influence of ...
Zhang Youhua - - 2009
BACKGROUND: Autonomic dysfunction, characterized by sympathetic activation and vagal withdrawal, contributes to the progression of heart failure (HF). Although the therapeutic benefits of sympathetic inhibition with beta-blockers in HF are clear, the role of increased vagal tone in this setting has been less studied. We have investigated the impact of ...
Kobayashi Seiju - - 2009
Recent studies have demonstrated the usefulness of 123I-meta-iodobenzylguanidine (MIBG) myocardial scintigraphy for the diagnosis of dementia with Lewy bodies (DLB). In this study, we investigated the relationship between decreased cardiac MIBG uptake and clinical symptoms in DLB. Thirty-six patients with probable DLB and six normal controls underwent MIBG scintigraphy. We ...
Almoznino-Sarafian Dorit - - 2009
BACKGROUND: Low heart rate variability (HRV) was found in various medical conditions including heart failure and acute myocardial infarction. Decreased HRV in these conditions predicted poor prognosis. METHODS: HRV was estimated in 133 unselected inpatients with relevant clinical bedside conditions by non-linear analysis derived from chaos theory, which calculates the ...
Surges R - - 2009
Reduced heart rate variability (HRV) may predispose to sudden unexpected death in epilepsy (SUDEP). We ascertained whether HRV predicts SUDEP in chronic epilepsy using a case-control design and investigated parameters of inter-ictal HRV in 14 patients (7 had died from SUDEP). No HRV parameter was associated with SUDEP. Thus, although ...
Netravathi M - - 2009
OBJECTIVES: Comparative evaluation of cardiac dysautonomia in spinocerebellar ataxias (SCA) and idiopathic sporadic ataxias (IA) not fulfilling the criteria of multiple system atrophy. MATERIAL AND METHODS: Cardiac autonomic functions were evaluated in 14 SCA (SCA1 = 6, SCA2 = 5 and SCA3 = 3) and 10 IA patients, comparable for ...
Schwartz Peter J - - 2009
This article reviews the background and rationale that have led to the first in-man study of the effects of direct chronic vagal stimulation for the management of heart failure. Following a brief discussion of the concept of "autonomic imbalance," the focus shifts to the wealth of pathophysiologic information gathered over ...
Flotats A - - 2009
Diabetes mellitus is a risk factor for cardiovascular morbidity and death. Cardiac autonomic diabetic neuropathy (CADN) is a common and serious complication of diabetes mellitus, which consists of damage to the autonomic nerve fibres that innervate the heart and blood vessels, resulting in alterations in heart rate control and vascular ...
Verrier Richard L - - 2009
Heart rate is a precisely regulated variable, which plays a critical role in health and disease. Numerous epidemiologic studies and large post-myocardial infarction trials have provided evidence that elevated resting heart rate is an independent risk factor for cardiac mortality. This body of knowledge has prompted the development and evaluation ...
Shehab Abdullah - - 2009
The aim was to compare measures of heart rate variability (HRV) in patients who presented with non-cardiac vascular episodes with age- and gender-matched control patients. One hundred and fifty patients, randomly selected from a cohort of 522 subjects, were enrolled in a screening study. Of these, 256 were identified to ...
Piccirillo Gianfranco G Dipartimento di Scienze dell'Invecchiamento, Università degli Studi di Roma La Sapienza, Rome, Italy. - - 2009
This study sought to find out more about the relationship between sympathetic and vagal nerve activity and the cardiac repolarization in a canine model of pacing-induced tachycardia congestive heart failure (CHF). The QT variability index (QTVI), a noninvasive marker of temporal cardiac repolarization dispersion, is among the risk factors for ...
Haensch Carl-Albrecht - - 2010
BACKGROUND: Postural orthostatic tachycardia syndrome (POTS) is a disorder of orthostatic intolerance characterised by excessive tachycardia of unknown aetiology. Whether this condition involves abnormal cardiac sympathetic innervation or function remains elusive. Meta-iodobenzylguanidine (MIBG) resembles guanethidine and is a pharmacologically inactive analogue of norepinephrine, which is similarly metabolised in noradrenergic neurons. ...
Koutelou Maria - - 2009
OBJECTIVE: We aimed at evaluating the combined use of heart rate variability (HRV), baroreflex sensitivity (BRS), and MIBG imaging in the risk stratification for sudden cardiac death (SCD) of patients with mild to moderate heart failure. METHODS: Twenty-five patients (17 male and 8 female, mean age 63 +/- 5 years, ...
Han Ying - - 2009
The current study was designed to determine whether castration with or without testosterone replacement resulted in changes in cardiac sympathetic nerve activity in rats with heart failure induced by isoproterenol. At eight weeks post-castration, dysfunction of the cardiac sympathetic nerve system was aggravated as indicated by elevated plasma norepinephrine, reduced ...
Galluzzi Samantha - - 2009
BACKGROUND: Cardiac autonomic dysfunction has been associated with cognitive impairment, but the underlying pathogenesis is complex and cerebral white matter lesions (WMLs) might be implicated. METHODS: Time and frequency heart rate variability (HRV) and visual rating of WMLs were carried out in 42 patients with mild cognitive impairment. RESULTS: After ...
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