Search Results
Results 401 - 450 of 1259
< 4 5 6 7 8 9 10 11 12 13 14 >
Guzzetti Stefano - - 2005
AIMS: To assess whether analysis of heart rate variability (HRV) from 24 h Holter recordings provides information about the mode of death (pump failure vs. sudden death) in chronic heart failure (CHF). METHODS AND RESULTS: We analysed 24 h HRV in 330 consecutive CHF patients in sinus rhythm. Indices derived ...
Folino Antonio Franco - - 2004
BACKGROUND: Severe ventricular arrhythmias represent one of the main causes of mortality after repair of tetralogy of Fallot. Their appearance is primarily caused by the large ventricular scar created by surgical intervention. However, the role of autonomic activity as a modulating factor should be considered. The aim of our study ...
Bickel A - - 2005
BACKGROUND: Carbon dioxide pneumoperitoneum (PP) is known to induce increased cardiac sympathetic expression. The role of the insufflated gas involved in this mechanism should be elucidated in an attempt to eliminate its possible serious consequences. METHODS: Twenty-five patients undergoing elective laparoscopic cholecystectomy were prospectively analyzed for cardiac autonomic nervous activity ...
Frenneaux M P - - 2004
A range of techniques for the assessment of autonomic tone are described. Impaired baroreflex control of heart period, measured in terms of heart rate variability or baroreflex sensitivity, is independently associated with adverse prognosis in patients with heart failure and following acute myocardial infarction. These techniques have not yet entered ...
Janszky I - - 2004
PURPOSE: Both heart rate variability (HRV) and inflammatory markers are carrying prognostic information in coronary heart disease (CHD), however, we know of no studies examining their relation in CHD. The aim of this study, therefore, was to assess the association between HRV and inflammatory activity, as reflected by the levels ...
Tverskaya M S - - 2004
Adrenergic plexuses in the myocardium and adrenal medulla were studied histochemically under conditions of increased left or right ventricular afterload. Under conditions of high afterload not accompanied by heart failure the density of sympathetic myocardial innervation remained unchanged in the loaded ventricle, but increased in the intact ventricle. Comparison of ...
Lovric Silvia Samarin - - 2004
OBJECTIVE: Complete allograft denervation occurs during heart transplantation. Partial ventricular sympathetic reinnervation may develop one year or later after transplantation and can be measured with iodine-123-meta-iodobenziylguanidine (MIBG) uptake. Aim of this study was to assess sinus node sympathetic reinnervation measured with heart rate variability and ventricular sympathetic reinnervation evaluated with ...
Sroka K - - 2004
About three quarters of myocardial ischemic events are triggered by the autonomic nervous system. The pathognomonic constellation is a combination of an almost complete withdrawal of tonic vagal activity with increased sympathetic activity. The reduction of tonic vagal activity, which is characteristic for ischemic heart disease, and the acute withdrawal ...
Cygankiewicz Iwona - - 2004
Heart rate turbulence is a novel method to identify patients at risk of cardiac death, and to date, there are no data concerning its circadian changes. In 46 coronary patients (mean age 63 +/- 8 years) with at least 100 ventricular premature beats in 24-hour Holter monitoring, turbulence onset, turbulence ...
Polak Gwidon - - 2004
INTRODUCTION: Parathormone (PTH) is a very potent uraemic toxin, which affects heart structure and function. PTH also plays the role in uraemic autonomic neuropathy (AN). The aim of the study was to investigate the relationship between high PTH level and AN assessed with frequency domain measures of heart rate variability ...
Demirtas Yener - - 2004
Surgery is accepted as one of the most demanding professions that create both physical and mental strain on the performers. Therefore, the authors aimed to elucidate the mental burden of surgeons, which is dedicated to operative stress. They also tested the hypotheses that participating in surgery creates mental stress on ...
Sztajzel Juan - - 2004
The autonomic nervous system (ANS) plays an important role not only in physiological situations, but also in various pathological settings such as diabetic neuropathy, myocardial infarction (MI) and congestive heart failure (CHF). Autonomic imbalance associating increased sympathetic activity and reduced vagal tone has been been strongly implicated in the pathophysiology ...
Terathongkum Sangthong - - 2004
Heart rate variability (HRV) is a simple noninvasive measurement for investigating autonomic influence on the cardiovascular system. HRV, the beat-to-beat alterations in heart rate, may be evaluated by time domain and frequency domain methods. HRV can be used as a predictor of risk or warning sign of cardiovascular diseases. Numerous ...
Manfrini Olivia - - 2004
AIMS: Cardio-cardiac reflexes may be evoked by both myocardial ischaemia and coronary occlusion itself. The aim of the study was to assess the intrapatient behaviour of autonomic nervous system balance during spontaneous and balloon-induced coronary ischaemia. METHODS AND RESULTS: We studied a group of patients admitted to the coronary care ...
Cygankiewicz Iwona - - 2004
This study evaluated the influence of coronary artery bypass grafting on heart rate turbulence (HRT) parameters assessed during 1-year follow-up in patients with coronary artery disease. HRT and heart rate variability (HRV) parameters significantly worsened 3 months after surgery. After 1 year, HRV parameters and turbulence onset returned to preoperative ...
Baratta Luigi - - 2004
We present a rare case of adult Still's disease with cardiac involvement (myocarditis and coronary arteritis). The autonomic nervous system function was evaluated by heart rate variability (HRV) analysis performed by 24-hour electrocardiographic recording during the acute phase of the disease and the remission (after 1 month and 1 year). ...
Lin Lian-Yu - - 2004
INTRODUCTION: Heart rate turbulence (HRT) is a powerful novel predictor for cardiovascular mortality. Chronic congestive heart failure is associated with abnormal HRT. Whether antiadrenergic beta-blocker therapy can restore control of HRT in patients with chronic congestive heart failure is unknown. METHODS AND RESULTS: A 24-hour Holter ECG recording was obtained ...
Lombardi Federico - - 2004
AIMS: To evaluate the presence of an abnormal autonomic modulation before, during and immediately after paroxysmal atrial fibrillation (PAF). METHODS AND RESULTS: We analysed Holter recordings of 65 patients with 110 PAF episodes lasting more then 30 s. Mean RR interval, co-efficient of variation and short-term heart rate variability were ...
Cygankiewicz Iwona - - 2004
INTRODUCTION: Heart rate variability (HRV) illustrates regulation of the heart by the autonomic nervous system whereas heart rate turbulence (HRT) is believed to reflect baroreflex sensitivity. The aim of this study was to determine the association between HRT and HRV parameters and the relationship between HRT parameters and heart rate ...
Balanescu Serban - - 2004
BACKGROUND: Prognosis after acute myocardial infarction (AMI) may be influenced by autonomic dysfunction that can be evaluated by assessment of heart rate variability (HRV). Its predictive value resulted from studies performed prior to large scale use of reperfusion therapy. We assessed the prognostic value of HRV parameters 1 year after ...
Wang Wei - - 2004
Congestive heart failure is a syndrome that is usually initiated by a reduction in pump function of the heart, i.e. a decrease in cardiac output. Initially, a reduction in cardiac output leads to unloading of baroreceptor reflex that, in turn, increases heart rate through vago-sympathetic mechanisms and total peripheral resistance ...
Roach Daniel - - 2004
OBJECTIVES: We sought to determine whether the long-range measures of heart rate variability (HRV)--the standard deviation of sequential 5-min heart period mean values (SDANN) and the heart period spectral amplitude in the ultra-low frequency band <0.0033 Hz (ULF)--had their origins partly in physical activity. BACKGROUND: The SDANN and ULF are ...
Malliani Alberto - - 2004
The efficacy of pharmacological beta-blockade in decreasing cardiac death in patients after myocardial infarction suggests the existence of sympathetic overactivity and indicates the importance of assessing its magnitude. The paper by Graham and co-workers in this issue of Clinical Science has attempted to address this issue by measuring muscle sympathetic ...
Esler Murray - - 2004
Panic disorder serves as a clinical model for testing whether mental stress can cause heart disease. Our own cardiologic management of panic disorder provides case material of recurrent emergency room attendances with angina and electrocardiogram ischemia, triggered arrhythmias (atrial fibrillation, ventricular fibrillation), and documented coronary artery spasm, in some cases ...
Akers Wendell S - - 2004
The purpose of this study is to determine the effect of clonidine on cardiac norepinephrine spillover utilizing an isolated rat heart preparation with attached cardiac sympathetic nerves. Following a 20-minute stabilization period, the sympathetic ganglion for each heart preparation was electrically stimulated with 10V and 2 Hz for 30 seconds ...
Goldstein David S - - 2004
Many concepts about acute and chronic effects of stress depend on alterations in sympathetic nerves supplying the heart. Physiologic, pharmacologic, and neurochemical approaches have been used to evaluate cardiac sympathetic function. This article describes a fourth approach that is based on nuclear scanning to visualize cardiac sympathetic innervation and function ...
Goncalvesova Eva - - 2004
Heart transplantation (HTx) is an accepted treatment for precisely defined patients with chronic congestive heart failure; however, as a result of the procedure, the graft is completely denervated. Our study focused on the catecholamine biosynthetic pathway, that is, the production of epinephrine, which is known to have positive chronotropic and ...
Rubinger Dvora - - 2004
BACKGROUND: The pathogenesis of haemodialysis-induced hypotension is multifactorial and may include autonomic nervous system dysfunction. The present study was undertaken to (i) determine heart rate variability (HRV) in chronic haemodialysis patients without and with haemodynamic instability (hypotension-prone) during ultrafiltration and (ii) identify patients at risk and the predictors of dialysis-related ...
Middlekauff Holly R - - 2004
Few clinical studies evaluating the efficacy of acupuncture in heart failure have been performed. These studies have focused on the acupoint Neiguan (P6) in patients experiencing heart failure and have variably reported either an acute increase in ventricular contractility and/or relaxation or no effect on ventricular contractility and/or relaxation. To ...
Acharya R - - 2004
The heart rate is a non-stationary signal, and its variation can contain indicators of current disease or warnings about impending cardiac diseases. The indicators can be present at all times or can occur at random, during certain intervals of the day. However, to study and pinpoint abnormalities in large quantities ...
Tambara Keiichi - - 2004
Reclining in the right lateral decubitus position in chronic heart failure (CHF) is a self-protective mechanism for normalizing impaired cardiac autonomic nervous activity (CANA). Candesartan, an angiotensin II receptor blocker, exerts beneficial effects on CANA and postural preferences in patients with CHF. We studied 15 patients with CHF due to ...
Wranicz Jerzy Krzysztof - - 2004
BACKGROUND: Although the relationship between sex steroid levels and coronary artery disease (CAD) has been the subject of many studies there are still controversies concerning the role of sex steroids in CAD. In patients with CAD, especially after a myocardial infarction, there is evidence for autonomic nervous system dysfunction. However, ...
Hadase Mitsuyoshi - - 2004
BACKGROUND: The present study examined whether the very low frequency (VLF) power of heart rate variability (HRV) is predictive of clinical prognosis in patients with congestive heart failure (CHF). METHOD AND RESULTS: The study recruited 54 consecutive CHF patients with emergency admission because of exacerbation of pulmonary congestion. Holter monitoring ...
Chowdhary Saqib - - 2004
Cardiac parasympathetic activity reduces susceptibility to potentially lethal ventricular arrhythmias in heart failure and ischemic heart disease. This influence is mediated in large part by antagonism of the adverse cardiac effects of sympathetic overactivity ("indirect" parasympathetic activity) in addition to the "direct" effects of muscarinic stimulation. Nitric oxide modulates parasympathetic ...
Friedman Howard S - - 2004
The purpose of this investigation was to determine whether heart rate variability (HRV) in atrial fibrillation (AF) can be related to any echocardiographic-derived measurements of cardiac dimensions or function. AF is characterized by marked HRV. Although HRV in normal sinus rhythm has been studied and shown to have important clinical ...
Fauchier Laurent - - 2004
The decrease in heart rate variability (HRV) might be related to the hemodynamic status in heart failure. However, HRV in patients with severe isolated right heart failure has not been extensively studied. This study compared HRV in patients with congestive heart failure (CHF) and in patients with isolated right heart ...
Schwab J O - - 2004
METHODS: Time and frequency domain analysis were conducted during a period of 600 s each. We performed a special protocol consisting of five different "pacing" periods: 1) recording of normal sinus rhythm (SR1); 2) atrial pacing with a rate 15% higher than the intrinsic heart rate; 3) ventricular pacing triggered ...
Arora Rishi - - 2004
Diastolic heart failure accounts for up to 40% of patients with congestive heart failure (CHF), and is associated with a better prognosis as compared to patients with systolic dysfunction. Nevertheless, patients with diastolic dysfunction have a significantly higher mortality as compared to the normal population. Reduced heart rate variability (HRV), ...
Gray Alrich L - - 2004
Intracardiac pathways mediating the parasympathetic control of various cardiac functions are incompletely understood. Several intracardiac ganglia have been demonstrated to potently influence cardiac rate [the sinoatrial (SA) ganglion], atrioventricular (AV) conduction (the AV ganglion), or left ventricular contractility (the cranioventricular ganglion). However, there are numerous ganglia found throughout the heart ...
Costoli Tania - - 2004
Repeated single exposures to social stressors induce robust shifts of cardiac sympathovagal balance toward sympathetic dominance both during and after each agonistic interaction. However, little evidence is available regarding possible persistent pathophysiological changes due to chronic social challenge. In this study, male CD-1 mice (n = 14) were implanted with ...
Meyer S - - 2004
Autonomic nervous system dysfunction is a common complication of ischemic stroke. Clinical and experimental data indicate hemispheric lateralization in the control of autonomic activity. The insular cortex has also been shown to play a crucial role in the central autonomic network. The aim of this study was to assess cardio-autonomic ...
Yeragani Vikram K - - 2004
In this study, we analyzed heart rate variability during sexual activity using complex demodulation, which is a useful technique to study continuous changes in different frequency bands over short periods of time. Complex demodulation has the advantage of having higher time resolution compared to spectral analysis. We quantified the low ...
Odreman Rodolfo O - - 2004
BACKGROUND: We studied the heart rate responses to the Valsalva maneuver in eight patients with documented past medical history of acute Chagas' disease. METHODS: Four patients were studied 8-21 months after the acute episode and four, 58-68 months thereafter (age 25+/-8.65 years M+/-S.D.). Seventeen healthy subjects of similar age were ...
Villar Juan C - - 2004
BACKGROUND: Although impaired cardio-vagal response characterizes full-blown Chagas' disease, this feature among otherwise healthy T. cruzi serology carriers (SERO[+]) requires confirmation. The purpose of this study was to determine whether abnormal cardio-vagal responses were different among SERO[+] subjects with varying ECG alterations. METHODS: We assessed cardio-vagal reflex response in 57 ...
Agelink Marcus W - - 2004
Numerous studies provide evidence that major depression (MD) is associated with certain disorders of cardiac autonomic nervous system (ANS) function, in particular, with an autonomic neurocardiac imbalance characterized by a low cardiovagal modulation, a raised sympathetic nerve activity and a high resting heart rate. We assume that such MD-associated cardiac ...
Laciar E - - 2004
The aim of this paper is to analyze the beat-to-beat variability of ventricular late potentials (LP) in high resolution ECG (HRECG) records of patients with Chagas' disease. In order to evaluate the LP activity, we propose a method which computes the bi-dimensional (2-D) cross-correlation between a template spectro-temporal (STM) of ...
Kishi F - - 2004
Mitral valve prolapse (MVP) is closely related to myocardial sympathetic nerve function. This study evaluated the presence of impaired myocardial sympathetic nerve function by Iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy in ten patients with MVP. For comparison, 15 healthy subjects without heart disease were investigated (control group). Single photon emission computed tomography (SPECT) ...
Dobrzycki S - - 2004
PURPOSE: Assessment of the gastroesophageal reflux disease (GERD) influence on myocardial ischemia and autonomic nervous system (ANS) activity. MATERIAL AND METHODS: In 50 patients with angiographically confirmed ischemic heart disease (IHD) in I-III CCS class, simultaneous 24-hour ECG and esophageal pH-metry monitoring was performed. We assessed: (1) GERD occurrence in ...
Alan Sait - - 2004
The purpose of this study is to examine clinical progress and hemodynamic and electrocardiologic features (QT depression and heart rate variability [HRV]) of patients exposed to a scorpion bite. Seventeen patients bitten by scorpions, and, as a control group, 15 healthy subjects were included in the study. Standard electrocardiograph (ECG) ...
Aydin Mustafa - - 2004
To analyze the function of cardiac autonomic regulation in patients with obstructive sleep apnea syndrome (OSAS), we enrolled 36 patients with OSAS and divided them according to the apnea hypopnea index (AHI) into 2 groups: Group I (n=19) had mild OSAS (AHI < 20) and Group II (n=17) had severe ...
< 4 5 6 7 8 9 10 11 12 13 14 >