Search Results
Results 401 - 450 of 1298
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Sugiura Masato - - 2006
BACKGROUND: The status of cardiac sympathetic nerve activity in patients with diastolic heart failure has not been fully understood. 123-I-metaiodobenzylguanidine cardiac images are valuable for evaluating cardiac sympathetic nerve activity. METHODS: We obtained 123-I-metaiodobenzylguanidine cardiac images from 34 consecutive patients with moderate heart failure and an ejection fraction of > ...
Adamson Philip B - - 2005
Continuous measurement of spontaneous heart rate variability is now possible from permanently implanted devices and may contain information useful in the chronic management of patients with congestive heart failure. Since heart rate variability semi-quantifies autonomic control of the heart, changes noted from continuous measurement provide insight into cardiac control system ...
Cohen-Solal Alain - - 2005
Carvedilol is a beta-blocking agent with antioxidant properties that has been shown to improve survival in chronic heart failure (CHF). Previous open-label studies have suggested that its use may have positive effects on the abnormalities of cardiac sympathetic innervation integrity and functioning. The present study aimed to test the hypothesis ...
Liang Chang-Seng - - 2006
Cardiac sympathetic transmitter stores are reduced in the failing heart. In this study, we proposed to investigate whether the reduction of cardiac sympathetic neurotransmitters was associated with increased interstitial norepinephrine (NE) and reactive oxygen species in congestive heart failure (CHF), using a microdialysis technique and salicylate to detect .OH generation. ...
Longin Elke - - 2006
BACKGROUND: Heart rate variability (HRV) reveals information on the functional state of the autonomic nervous system (ANS) in neonates. During severe illness, heart rate variability is impaired. AIM: This study was initiated to measure the changes in HRV in neonates during extracorporeal membrane oxygenation (ECMO) and recovery from severe respiratory ...
Gurses Dolunay - - 2005
OBJECTIVE: Cardiac complication is one of the major causes of death in patients with thalassaemia major. Heart rate variability is a non-invasive index of neuronal modulation of heart rate. In this study, autonomic functions of the heart in a preclinical stage of heart disease were evaluated in 48 thalassaemic patients ...
Matsui T - - 2005
The impaired balance of the low-frequency/high-frequency ratio obtained from spectral components of RR intervals can be a diagnostic test for sepsis. In addition, it is known that a reduction of heart rate variability (HRV) is useful in identifying septic patients at risk of the development of multiple organ dysfunction syndrome ...
Suzuki Masahiko - - 2006
BACKGROUND: Iodine-123-labeled metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy has been used to evaluate cardiac sympathetic denervation in Lewy body disease (LBD) including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Patients with LBD had marked reductions in cardiac MIBG accumulation, indicative of severe impairment of the cardiac sympathetic nervous systems. However, ...
Chan H L - - 2005
Spectral analysis of heart rate variability provides a probe to assess the function of the sympathetic and parasympathetic nervous systems. Time-frequency analysis of heart rate variability is useful for investigating autonomic nervous function in patients with syncope or non-sustained ventricular tachycardia, or in anaesthesia, etc. In this paper, we developed ...
Garet Martin - - 2005
PURPOSE: Heart rate variability (HRV) indices are powerful independent prognostic factors of cardiovascular events and all cause mortality in patients with chronic heart failure (CHF). This study evaluates the influence of lifestyle on HRV in CHF patients. METHODS: Thirty-nine CHF patients (33 men, ischemic/dilated cardiomyopathy (18/21), 52.4 +/- 11.2 yr, ...
Anastasiou-Nana Maria I - - 2005
Autonomic nervous system dysfunction is common in congestive heart failure (CHF) and is believed to predispose patients to an increased risk of death. This study aimed to assess the prognostic significance of heart rate variability (HRV) measurements in conjunction with scintigraphic imaging using metaiodobenzylguanidine (MIBG) labeled with iodine-123 (I-123-MIBG), which ...
Kubo Toshihiko - - 2005
We have documented a pre-junctional beta-2 adrenoceptor mediated reduction in cardiac norepinephrine spillover (CNES) in heart failure patients receiving chronic beta-blockade. Our present objective was to ascertain the consequence of this decrease for vagal heart rate (HR) regulation by determining CNES, arterial baroreflex sensitivity for HR (BRS) and arterial baroreflex ...
Guzzetti Stefano - - 2005
BACKGROUND: Sympathetic and parasympathetic systems are considered the principal rapidly reacting systems that control heart rate. METHODS AND RESULTS: We propose a symbolic analysis series to quantify the prevalence of sympathetic or parasympathetic cardiac modulation. This analysis decomposes the heart rate variability series in patterns lasting 3 beats and classifies ...
Burri Haran - - 2006
INTRODUCTION: Studies evaluating changes in HRV preceding the onset of ventricular arrhythmias using conventional techniques have shown inconsistent results. Time-frequency analysis of HRV is traditionally performed using short-term Fourier transform (STFT). Wavelet transform (WT) may however be better suited for analyzing non-stationary signals such as heart rate recordings. METHODS AND ...
Stöllberger Claudia - - 2006
The findings of Kawasaki et al. [T. Kawasaki, A. Azuma, T. Taniguchi, et al. Heart rate variability in adult patients with isolated left ventricular noncompaction. Int J Cardiol 2005;99:147-150.] raise the following questions: why was dilated cardiomyopathy not investigated? How many of the patients with left ventricular hypertrabeculation/noncompaction (LVHT) showed ...
Gehi Anil A Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai School of Medicine, New York, New York, - - 2005
We examined the association between anemia (hemoglobin < or =12 g/dl) and 6 indexes of heart rate variability (HRV) as measured by 24-hour ambulatory electrocardiography in a cross-sectional study of 874 outpatients who had stable coronary heart disease. Of 90 participants who had anemia, 29% to 41% had low HRV, ...
Danson Edward J - - 2005
Nitric oxide (NO) is a potent modulator of cardiac and vascular regulation. Its role in cardiac-autonomic neural signaling has received much attention over the last decade because of the ability of NO to alter cardiac sympathovagal balance to favor more anti-arrhythmic states. Complexity and controversy have arisen, however, because of ...
Milicević Goran - - 2005
Heart rate variability (HRV) reflects an influence of autonomic nervous system on heart work. In healthy subjects, ratio between low and high frequency components (LF/HF ratio) of HRV spectra represents a measure of sympatho-vagal balance. The ratio was defined by the authorities as an useful clinical tool, but it seems ...
Moak Jeffrey P - - 2005
BACKGROUND: Upper thoracic sympathectomy is used to treat several disorders. Sympathetic nerve fibers emanating from thoracic ganglia innervate the heart. Whether unilateral or bilateral upper thoracic sympathectomy affects cardiac sympathetic innervation in humans in vivo has been unclear. OBJECTIVES: The purpose of this study was to assess whether thoracic sympathectomy ...
De Jong Marla J - - 2005
Heart rate is not static, but rather changes continuously in response to physical and mental demands. In fact, an invariant heart rate is associated with disease processes such as heart failure. Heart rate variability analysis is a noninvasive technique used to quantify fluctuations in heart rate. In this article, the ...
Kaye David - - 2005
The documentation of preferential activation of the cardiac sympathetic outflow in patients with heart failure swept aside an entrenched notion that there was a functional sympathetic denervation of the failing heart and provided a theoretical basis for the clinical evaluation of beta-adrenergic blocker therapy in this condition. The demonstration that ...
Carpeggiani Clara - - 2005
AIMS: To investigate personality traits and sympatho-vagal modulation of heart rate variability (HRV) during acute myocardial infarction (AMI), assessing their relationships and their long-term prognostic value. METHODS AND RESULTS: Psychological traits and 24 h HRV were prospectively investigated in 246 patients at discharge of an AMI. Patients were followed-up to ...
Hallstrom Alfred P - - 2005
OBJECTIVE: To assess the value for improving risk stratification of measures, unadjusted and adjusted for heart rate, of heart rate variability (HRV) and heart rate turbulence (HRT) based on 2- to 24-h ambulatory electrocardiographic recordings; and to relate this to the decision to use an implantable cardiac defibrillator (ICD) and ...
Wu Zhong-Kai - - 2005
OBJECTIVE: Heart rate variability (HRV) is the most frequently used noninvasive diagnostic method in the assessment of cardiac autonomic control. The clinical relevance of HRV, especially nonlinear HRV in CPB patients has not been well studied. Short brief myocardial ischemia has been reported to influence HRV. We therefore hypothesis that ...
Paton J F R - - 2005
We review the pattern of activity in the parasympathetic and sympathetic nerves innervating the heart. Unlike the conventional textbook picture of reciprocal control of cardiac vagal and sympathetic nervous activity, as seen during a baroreceptor reflex, many other reflexes involve simultaneous co-activation of both autonomic limbs. Indeed, even at 'rest', ...
Chen Lung Chi - - 2005
Long-term exposure to fine particulate air pollution (PM2.5) has been associated increased risk of death from cardiopulmonary diseases. Cardiac function parameters have also been affected by ambient particulate matter (PM) exposure, including heart-rate variability (HRV), a measure of autonomic function that has been recognized as a well-defined, quantitative indicator of ...
Tuomainen Petri - - 2005
Decreased heart rate variability (HRV) and heart rate turbulence (HRT) are independent predictors of mortality after acute myocardial infarction (AMI). There are no previous studies on the relationship between warm-up phenomenon and cardiac autonomic control in stable coronary artery disease (CAD). We investigated the responses in HRV to repeated exercise ...
Bär K J - - 2005
An increased heart rate has been reported in schizophrenia. It is unclear whether this is due to disease-related autonomic nervous system changes or a side effect of antipsychotic medication. Altered cardiac autonomic function might to some extent account for the elevated cardiovascular mortality rate of schizophrenic patients. We assessed heart ...
Janszky I - - 2005
To test the hypothesis that alcohol consumption is positively related to heart rate variability (HRV) in women with coronary heart disease (CHD) and therefore that cardiac autonomic activity is potentially implicated in the mediation of the favourable effects of moderate drinking. Cross sectional study of female patients who survived hospitalisation ...
Malliani Alberto - - 2005
Power spectrum analysis of cardiovascular signal variability, and in particular of the RR period (heart rate variability, HRV), is a widely used methodology for investigating autonomic neural regulation in health and disease that can quantify the sympathovagal balance modulating the sinus node pacemaker. In some cases, it can also quantify ...
Iwasaki Masayoshi - - 2005
To examine the relationship among heart rate turbulence parameters, arterial baroreflex sensitivity, and cardiac sympathetic nerve activity, 15 patients with acute myocardial infarction, presenting with sinus rhythm and > or = 3 ventricular premature beats/24 hr were studied at least 2 weeks after acute myocardial infarction. Turbulence onset (TO) and ...
Binkley Philip F - - 2005
BACKGROUND: In addition to its well-recognized role in the regulation of vascular tone, nitric oxide modulates sympathetic and parasympathetic nervous system activities. Abnormalities of both autonomic control and nitric oxide synthase activity are known to occur in patients with congestive heart failure. Recently, a polymorphism of the promoter of the ...
Amino Takeshi - - 2005
In the last few years, cardiac sympathetic dysfunction in Parkinson disease (PD) has been postulated on the basis of decreased cardiac uptake of sympathoneural imaging tracers. However, the pathological substrate for the dysfunction remains to be established. We examined the left ventricular anterior wall from postmortem specimens with immunohistochemical staining ...
Stein Phyllis K - - 2005
Traditional time and frequency domain heart rate variability (HRV) have cardiac patients at risk of mortality post-myocardial infarction. More recently, non linear HRV has been applied to risk stratification of cardiac patients. In this review we describe studies of non linear HRV and outcome in cardiac patients. We have included ...
Yuyama Reisuke - - 2005
BACKGROUND: Iodine 123-metaiodobenzylguanidine (MIBG) imaging has been used to assess cardiac sympathetic nerve abnormalities. To determine the role of MIBG imaging as a measure of generalized sympathetic nerve activity, MIBG imaging was evaluated with muscle sympathetic nerve activity (MSNA) and plasma norepinephrine (noradrenaline) level in patients with old myocardial infarction. ...
Francis Johnson - - 2005
Initial acceleration and a subsequent deceleration of sinus rhythm following a ventricular ectopic beat with a compensatory pause has been termed heart rate turbulence (HRT). The changes in sinus rhythm are thought to be mediated by a baroreflex response to the lower stroke volume of the ectopic beat. HRT is ...
Stein Phyllis K - - 2005
INTRODUCTION: Decreased heart rate variability (HRV) and abnormal nonlinear HRV shortly after myocardial infarction (MI) are risk factors for mortality. Traditional HRV predicts mortality in patients with a range of times post-MI, but the association of nonlinear HRV and outcome in this population is unknown. METHODS AND RESULTS: HRV was ...
Schulz Holger - - 2005
Epidemiological studies of the past decades have provided a strong body of evidence that elevated levels of ambient particulate air pollution (PM) are associated with increased cardiovascular and respiratory morbidity and mortality. Exacerbations of ischemic and/or arrhythmic cardiac diseases have been linked to PM exposure. At a workshop held at ...
Balocchi R R Institute of Clinical Physiology, National Research Council, Pisa, Italy. email: - - 2005
The aim of the present study was to investigate the possible hypnotizability-related modulation of heart activity during nociceptive stimulation (pressor pain) and during nociceptive stimulation associated with the suggestion of analgesia in not hypnotized healthy individuals with a high (Highs) and a low (Lows) hypnotic susceptibility. ECG and respirogram were ...
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 Y Department of Plastic, Reconstructive, and Aesthetic Surgery, and Cardiology, Gazi University Faculty of Medicine, Ankara, Turkey. - - 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 ...
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