Search Results
Results 201 - 250 of 1297
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Rutjanaprom Wasarut - - 2009
BACKGROUND: Cardiac failure remains the major cause of death in beta-thalassemia major (TM). Reduced heart rate variability (HRV) is associated with a higher risk of arrhythmias after myocardial infarction and heart failure. We evaluated HRV in TM patients and its relationship with hemodynamics and echocardiographic parameters during a 6-month follow-up. ...
Kosaka Toshimitsu - - 2009
Left ventricular (LV) diastolic dysfunction is related to increased cardiac sympathetic activity. We investigated the effect of cilnidipine, an L/N-type calcium channel blocker, on LV diastolic function and cardiac sympathetic activity in patients with hypertensive heart disease (HHD) using radionuclide myocardial imaging. Thirty-two frame electrocardiography (ECG) -gated (99m)Tc-sestamibi (MIBI) myocardial ...
Buccelletti E - - 2009
BACKGROUND: Heart rate, measured as beat-to-beat intervals, is not constant and varies in time. This property is known as heart rate variability (HRV) and it has been investigated in several diseases, including myocardial infarction (MI). The main hypothesis is that HRV embed some physiological processes that are characteristics of regulatory ...
Heinz Lara - - 2009
BACKGROUND: Sudden cardiac death in athletes is more common than in the general population. Routine screening procedures are performed to identify competitors at risk. A new Holter-based parameter analyzes variation of the ventricular repolarization (TVar). The aim of this study was to evaluate differences in electrocardiogram (ECG), Echo, and Holter ...
Valentini Mariaconsuelo - - 2009
In both physiologic and pathological conditions, instantaneous heart rate value is the result of a rather complex interplay. It constantly varies under the influence of a number of factors: nonmodifiable and modifiable ones. Pharmacologic blockade with beta-adrenergic antagonists and/or with parasympathetic antagonists such as atropine have permitted the identification of ...
Richardson T - - 2009
BACKGROUND: Cardiac autonomic dysfunction post ST-segment elevation myocardial infarction (STEMI) has been linked to an excess risk of premature cardiovascular morbidity and mortality above those with normal autonomic function post-STEMI. AIM: The aim of this study was to evaluate the effect of acute ingestion of coffee on autonomic function and ...
Maestri Roberto - - 2009
Despite a well established prognostic value in cardiac patients, heart rate variability (HRV) indexes have been little used in the clinical setting. Poor reliability of the measurements might be a possible explanation. In this study we assessed the reliability of short-term HRV indexes in post myocardial infarction (MI) patients. We ...
Adams Jenny - - 2009
OBJECTIVES: To determine whether a controlled breathing programme increases heart rate variability following an acute myocardial infarction and/or coronary artery bypass graft surgery. RATIONALE: Heart rate variability is reduced following a myocardial infarction, and low heart rate variability is associated with a high mortality risk. By changing tidal volume and ...
Baumert Mathias - - 2009
Changes in measures of heart rate variability (HRV) have been associated with an increased risk for sudden cardiac death. The mechanisms underlying this association are not known. The objective of this study was to assess the relationship between the amount of norepinephrine (NE) released from the cardiac sympathetic terminals and ...
Buchner Teodor - - 2009
Human heart rate is moderated by the autonomous nervous system acting predominantly through the sinus node (the main cardiac physiological pacemaker). One of the dominant factors that determine the heart rate in physiological conditions is its coupling with the respiratory rhythm. Using the language of stochastic processes, we analyzed both ...
Glass Leon - - 2009
In June 2008, the editors of Chaos decided to institute a new section to appear from time to time that addresses timely and controversial topics related to nonlinear science. The first of these deals with the dynamical characterization of human heart rate variability. We asked authors to respond to the ...
McGlone Laura - - 2009
We undertook a study to describe changes in heart rate variability (HRV) postoperatively in children undergoing cardiac bypass surgery for congenital heart disease (CHD). HRV was recorded for a 1-h period preoperatively and a 24-h period postoperatively in 20 children with CHD. We found a highly significant reduction in HRV ...
Wernli Gwenaelle - - 2009
Myocardial infarction induces sympathetic axon sprouting adjacent to the necrotic region, and this has been implicated in the etiology of arrhythmias resulting in sudden cardiac death. Previous studies show that nerve growth factor (NGF) is essential for enhanced post-infarct sympathetic sprouting, but the cell types necessary to supply this neurotrophic ...
Folino Antonio F - - 2009
AIMS: Epidemiological studies show that peak exposure to air pollution is associated with increased morbidity and mortality from cardiovascular events. Panel and controlled exposure studies show that particulate matter (PM) may influence the parasympathetic regulation of the heart. The aim of this study was to concurrently measure individual exposure to ...
Wahab A - - 2009
To study the effect of Heart Rate Variability (HRV) and QT dispersion (QTd) in patients presenting with acute ST elevation myocardial infarction (STEMI). 100 patients of Acute myocardial infarction (AMI) were evaluated by history and examination. Electrocardiogram (ECG) and Holter monitoring was done in all patients. HRV, QTd, Standard Deviation ...
Neumann Serina A - - 2009
Previous evidence suggests that the dual-specific A kinase-anchoring protein 2 functional polymorphism (AKAP10 (A/G) I646V) influences heart rate (HR) and heart rate variability (HRV) in mice and humans (N=122) with cardiovascular disease. Here, we asked whether this AKAP10 variant predicts HR and HRV in a large sample of healthy humans. ...
Tobaldini Eleonora E Department of Clinical Sciences, Internal Medicine II, L. Sacco Hospital, University of Milan, Via G.B. Grassi 74, Milan, - - 2009
Congestive heart failure (CHF) is associated with neurohumoral activation. Only very few studies have examined the progression of autonomic dysfunction in CHF in humans and scanty data are available in animal models of CHF. This study was performed to assess the changes in cardiac autonomic modulation during the progression of ...
Huikuri Heikki V - - 2009
Heart rate variability (HRV) has been conventionally analysed with time- and frequency-domain methods, which measure the overall magnitude of RR interval fluctuations around its mean value or the magnitude of fluctuations in some predetermined frequencies. Analysis of heart rate dynamics by novel methods, such as heart rate turbulence after ventricular ...
Goldstein David S - - 2009
There is substantial interest in identifying biomarkers to detect early Parkinson disease (PD). Cardiac noradrenergic denervation and attenuated baroreflex-cardiovagal function occur in de novo PD, but whether these abnormalities can precede PD has been unknown. Here we report the case of a patient who had profoundly decreased left ventricular myocardial ...
Grassi Guido - - 2009
Congestive heart failure (CHF) is characterized not only by profound abnormalities in the haemodynamic profile but also by changes in sympathetic cardiovascular function. These neurogenic abnormalities are important features of the disease that can affect the prognosis of CHF and to become a target for therapeutic intervention. This article addresses ...
Hamaad Ali - - 2009
BACKGROUND: Acute coronary syndromes (ACS) are characterized by abnormal heart-rate variability (HRV) and biomarkers of endothelial damage and thrombosis. HYPOTHESIS: We hypothesized an association between these factors in patients with ACS. METHODS: We studied 99 patients with ACS measuring HRV and plasma markers of endothelial damage/dysfunction (von Willebrand factor, vWF) ...
Werdan Karl - - 2009
In sepsis, systemic inflammatory response syndrome (SIRS), and multiorgan dysfunction syndrome (MODS), a severe prognostically relevant cardiac autonomic dysfunction exists, as manifested by a strong attenuation of sympathetically and vagally mediated heart rate variability (HRV). The mechanisms underlying this attenuation are not limited to the nervous system. They also include ...
Moak Jeffrey P - - 2009
BACKGROUND: Power spectral analysis of heart rate variability (HRV) has been used to indicate cardiac autonomic function. High-frequency power relates to respiratory sinus arrhythmia and therefore to parasympathetic cardiovagal tone; however, the relationship of low-frequency (LF) power to cardiac sympathetic innervation and function has been controversial. Alternatively, LF power might ...
Grigorean Valentin Titus - - 2009
The aim of this article is to analyze cardiac dysfunctions occurring after spinal cord injury (SCI). Cardiac dysfunctions are common complications following SCI. Cardiovascular disturbances are the leading causes of morbidity and mortality in both acute and chronic stages of SCI. We reviewed epidemiology of cardiac disturbances after SCI, and ...
Lujan Heidi L - - 2009
Midthoracic spinal cord injury is associated with ventricular arrhythmias that are mediated, in part, by enhanced cardiac sympathetic activity. Furthermore, it is well known that sympathetic neurons have a lifelong requirement for nerve growth factor (NGF). NGF is a neurotrophin that supports the survival and differentiation of sympathetic neurons and ...
Nanjo Shuji - - 2009
BACKGROUND: Because increased sympathetic nervous activity (SNA) in patients with dilated cardiomyopathy (DCM) associated with sleep breathing disorder (SBD) is known to deteriorate the prognosis of cardiac failure, (123)I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy was used as the investigative tool in the present study. METHODS AND RESULTS: The study group comprised 53 ...
Björkander Inge - - 2009
BACKGROUND: Heart rate variability (HRV) reflects the balance between cardiac parasympathetic and sympathetic autonomic influences. Reduced HRV has adverse prognostic implications. The time course for changes in HRV over prolonged periods of time and the influence of an acute coronary event on HRV are not well established. METHODS: Heart rate ...
Ieda Masaki - - 2009
The heart is abundantly innervated, and the nervous system precisely controls the function of this organ. The density of cardiac innervation is altered in diseased hearts, which can lead to unbalanced neural activation and lethal arrhythmia. For example, diabetic sensory neuropathy causes silent myocardial ischemia, characterized by loss of pain ...
Chen Grace P - - 2009
Congestive heart failure increasingly contributes to the overall morbidity and mortality associated with cardiovascular disease. Although significant advances in therapies allow patients to feel better and have improved functional status and survival, not all patients respond equally to these therapies. Moreover, for any given level of left ventricular systolic dysfunction, ...
Syed Zeeshan - - 2009
Unstable conduction system bifurcations following ischemia and infarction are associated with variations in the electrocardiographic activity spanning the heart beat. In this paper, we investigate a spectral energy measure of morphologic differences (SE-MD) that quantifies aspects of these changes. Our measure uses a dynamic time-warping approach to compute the time-aligned ...
Smilde Tom D J - - 2009
BACKGROUND: In contrast to patients with moderate to severe chronic heart failure (CHF), data regarding long-term outcome in patients with mild CHF are scarce. We examined the place of Holter monitoring to study the prognostic value of ventricular arrhythmias and heart rate variability (HRV) in patients with mild to moderate ...
Ogawa Masahiro - - 2009
Myocardial infarction results in denervation, followed by neural remodeling characterized by nerve sprouting and heterogeneous sympathetic hyperinnervation throughout the myocardium. There is an association between the density of sympathetic nerves and occurrence of cardiac arrhythmia in humans. Autonomic nerve recording in ambulatory dogs showed a close association between autonomic nerve ...
Zhou Shu-Xian - - 2009
AIMS: This study investigated ventricular electrophysiological characteristics and the correlation between these parameters and heart rate variability (HRV) and baroreflex sensitivity (BRS) in a canine congestive heart failure (CHF) model. METHODS AND RESULTS: Haemodynamics, HRV, BRS, and ventricular electrophysiological variables were measured 4-5 weeks after sham operation (control dogs) and ...
Nishimura Masato - - 2010
We prospectively investigated whether cardiac autonomic imbalance is associated with sudden cardiac death (SCD) among a group of hemodialysis patients with left ventricular hypertrophy (LVH). In a prospective cohort study, we enrolled 196 asymptomatic patients on chronic hemodialysis who had LVH as determined by echocardiography and had undergone twenty-four-hour ambulatory ...
Fu Liang-Wu - - 2009
The heart at the time of Sir William Harvey originally was thought to be an insensate organ. Today, however, we know that this organ is innervated by sensory nerves that course centrally though mixed nerve pathways that also contain parasympathetic or sympathetic motor nerves. Angina or cardiac pain is now ...
Lewek Joanna - - 2009
BACKGROUND: Deceleration capacity (DC) is a novel electrocardiography (ECG) parameter characterizing the overall capacity of slowing down the heart rate. The aim of this study was to evaluate clinical and ECG covariates of DC in patients with the first episode of ST-segment elevation myocardial infarction (STEMI) treated with primary angioplasty. ...
Mwamure Peter - - 2009
A 70-year-old male presented to hospital with both anterior ST elevation myocardial infarction and spontaneous oesophageal rupture (Boerhaave's syndrome). He underwent primary angioplasty and stenting for a lesion of the left anterior descending in addition to cardiothoracic surgery for the oesophageal rupture. This combination of pathologies is a rare entity ...
Karp Erez - - 2009
OBJECTIVES: To evaluate the prognostic significance of early ultra-short-term heart rate variability (HRV) measurement in patients admitted for ST-elevation myocardial infarction (STEMI). METHODS: HRV was calculated retrospectively from the standard admission and discharge 10-second ECG of 196 consecutive patients with STEMI. Reduced HRV was defined as standard deviation of N-N ...
Mironova Tatyana - - 2009
The purpose of this study was to present results of special examination and prospective observation of patients with coronary artery disease (CAD) and angina pectoris (AP) in practical cardiology. Except standard cardiological methods, we used high-resolution rhythmocardiography and apparatus-program complex for registration and analysis of the heart rate variability. There ...
Longenecker J C - - 2009
OBJECTIVE: The aim of this study was to investigate the left-ventricular (LV) mass-adjusted association between low heart rate variability (HRV) and atherosclerotic cardiovascular disease (ASCVD) among hemodialysis patients in Kuwait. SUBJECTS AND METHODS: One hundred and eight patients were enrolled in the study. HRV time domain measures were obtained by ...
Mishra Archana - - 2009
Increased heart rate during graded exercise is related to increased sympathetic activity and withdrawal of vagal tone. Return of heart rate towards baseline immediately after exercise is usually due to resurgence of vagal tone. As it is an established fact that cardiovascular morbidity and mortality in part has direct relation ...
Gang Yi - - 2009
Heart rate variability (HRV) is a beat-to-beat variation in cardiac cycle length resulting from autonomic influence on the sinus node of patients in sinus rhythm. The importance of HRV as a risk stratifier has been well accepted, particularly in survivors of myocardial infarction. Large clinical trials are still needed to ...
Anselmino Matteo - - 2009
BACKGROUND: Spinal cord stimulation (SCS) has proven antianginal and antiischemic effects in severe coronary artery disease patients, minimizing frequency, intensity, and duration of pain. The mechanism explaining these effects has been detected in a sympathicolytic effect of the SCS. We monitored 30-minute-long recordings of the heart rate variability (HRV) and ...
Omerbegovic Meldijana - - 2009
In the last decades analysis of heart rate variability has emerged as a new useful tool for assessing the changes in autonomic tone that influences cardiovascular function. High variability of oscillations and the integrated physiologic activities of heart and cardiovascular system isassociated with physiologic functioning. Irregularity of the length of ...
Porto Luiz Guilherme Grossi - - 2009
BACKGROUND: Wrist-worn heart rate monitors have not been extensively validated for heart rate variability analysis. The purpose of this study was to compare time-domain variability of heart interval series (R-Ri) recorded by the Polar S810 monitor (Polar Electro Oy, Kempele, Finland) and the conventional electrocardiogram (ECG). METHODS: Agreement was verified ...
Ksela Jus - - 2009
Non-linear analyses of heart rate dynamics reveal subtle changes not evident from conventional heart rate variability measures. Traditionally, the information was inferred from 24-hour ECG recordings, making it less suitable for clinical application. Moreover, only few studies have attempted to evaluate the reliability of non-linear analyses in relation to varying ...
Sherman Warren - - 2009
Skeletal myoblast (SM) implantation promotes recovery of myocardial function after ischemic injury. Clinical observations suggest an association of SM implantation and ventricular arrhythmias. Support for this link has been sought in animal studies, but none employing models of congestive heart failure. In a canine model of postinfarction congestive heart failure ...
Hildreth Victoria V Institute of Human Genetics, Newcastle University, Centre for Life, Central Parkway, Newcastle upon Tyne, United Kingdom. - - 2009
Maintenance of homeostatic circulation in mammals and birds is reliant upon autonomic innervation of the heart. Neural branches of mixed cellular origin and function innervate the heart at the arterial and venous poles as it matures, eventually coupling autonomic output to the cardiac components, including the conduction system. The development ...
Sunagawa Kenji - - 2009
In this invited session, we would like to address the impact of bionic neuromodulation on cardiovascular diseases. It has been well established that cardiovascular dysregulation plays major roles in the pathogenesis of cardiovascular diseases. This is the reason why most drugs currently used in cardiology have significant pharmacological effects on ...
Vasu V V The Institute of Electronics, Communications and Information Technology, Queen's University Belfast, Belfast BT3 9DT, Northern Ireland, - - 2009
A 5.8-GHz ISM-Band radio-frequency sensor has been developed for non-contact measurement of respiration and heart rate from stationary and semi-stationary subjects at a distance of 0.5 to 1.5 meters. We report on the accuracy of the heart rate measurements obtained using two algorithmic approaches, as compared to a reference heart ...
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