Search Results
Results 151 - 200 of 728
1 2 3 4 5 6 7 8 9 10 >
Dilaveris Polychronis - - 2004
BACKGROUND: Although the electrocardiographic (ECG) features of early repolarization (ER) have been studied extensively, no systematic quantification of ventricular repolarization in subjects with ER has been conducted so far. METHODS: The objective of the present study was to evaluate ECG and spatial vectorcardiographic (VCG) descriptors of ventricular repolarization in ER ...
Lancellotti Patrizio - - 2004
To assess the predictors of rapid QRS widening in patients with chronic ischemic left ventricular dysfunction, 82 patients who underwent > or =2 electrocardiograms and exercise Doppler echocardiography were studied. In a multivariate analysis, left ventricular end-diastolic volume, a large increase in mitral regurgitant volume during exercise, and diabetes emerged ...
Stolen Kira Q - - 2004
BACKGROUND: Exercise intolerance is a hallmark symptom in patients with heart failure; however, myocardial factors contributing to the limited exercise capacity are not fully characterized. METHODS: Twenty patients with stable heart failure resulting from idiopathic dilated cardiomyopathy (DCM) and 13 controls were studied. Myocardial perfusion, biventricular oxidative metabolism, and insulin-stimulated ...
Werber-Zion Galila - - 2004
PURPOSE: Deterioration in left ventricular function is a more sensitive marker of myocardial ischemia during exercise than ST segment depression. The current study was designed to evaluate left ventricular function during one-repetition-maximum (1-RM) strength testing and resistance exercise in cardiac patients with moderate left ventricular dysfunction. METHODS: Using echocardiographic methods, ...
Pigozzi F - - 2004
AIM: Physical activity, when vigorous, is not devoided of arrhythmic risk. Since the risk of developing arrhythmias increase as an otherwise healthy person ages, the question arises as to whether high intensity physical activity could be dangerous in the elderly person. The present study addressed the incidence of arrhythmias in ...
Ozdemir Kurtulus - - 2004
Postmenopausal hormone replacement therapy (HRT) has usually been evaluated the relationship with atherosclerotic disease, whereas its effect on direct cardiac functions hasn't been investigated in detail. This study was planned to investigate the long-term effects of HRT on cardiac functions and exercise performance. Thirty-six postmenopausal women (mean age: 51 +/- ...
Saito K - - 2004
The purpose of this study was to evaluate the potential relationship between left ventricular systolic and diastolic function and maximal oxygen uptake in female college rowers. We assessed resting left ventricular systolic and diastolic function in 22 female college rowers (mean age, 19 y) utilizing M-mode, two-dimensional and Doppler echocardiography ...
Kharin Sergei N - - 2004
Activation and recovery sequences were mapped by means of 64-channel synchronous recording of extracellular potentials on ventricular epicardium in chickens. Ventricular epicardium was depolarized due to multiple breakthroughs. The recovery of ventricular epicardium occurs from the apex to the base of heart and does not repeat the activation sequence. Gradients ...
Levermann Nette - - 2003
BACKGROUND: Direct observations of underwater behaviour of free-living marine mammals are rare. This is particularly true for large and potentially dangerous species such as the walrus (Odobenus rosmarus). Walruses are highly specialised predators on benthic invertebrates - especially bivalves. The unique feeding niche of walruses has led to speculations as ...
Wu Yi - - 2003
A continuous flow left ventricle assist device (LVAD), which is mainly composed of a continuous flow blood pump and a physiological controller, has only one control input, the rotational speed of the pump, but at least three performance criteria to meet. The challenge for the physiological controller of a long-term ...
Mullins Paul G - - 2003
The reproducibility of single-voxel spectroscopic measures in a stable schizophrenic patient population is reported. Spectra acquired 1 week apart, in the left frontal white matter and left caudate nucleus of 12 patients, were analyzed using both frequency and time-domain techniques. No significant change in mean concentrations for N-acetylaspartate (NAA), choline ...
Rozenberg V D - - 2003
New geometric characteristics of the right ventricle depended on the localization of macrofocal transmural scars in the left ventricle of postinfarction heart. Most pronounced changes in the right ventricle were observed during dilatational and hypertrophic remodeling of the heart. The increase and decrease in the volume were most frequently occurring ...
Giordano Ugo - - 2003
An 11-year-old female, in apparent good health, was referred to our Institute because of exercise-induced left bundle branch block detected during a Master's step test performed to obtain the clearance for competitive sport. The tests that we performed to investigate the possible causes were all negative. We suspect, however, that ...
Izawa Hideo - - 2003
AIMS: Impaired coronary microcirculation is thought to contribute to myocardial ischaemia, causing an abnormal increase in left ventricular end-diastolic pressure during exercise in individuals with hypertrophic cardiomyopathy. The effects of nicorandil on left ventricular end-diastolic pressure during exercise were examined in patients with this condition. METHODS AND RESULTS: Left ventricular ...
Vardi Yoram - - 2003
BACKGROUND: Erectile dysfunction (ED) is frequently observed in male cardiovascular disease (CVD) patients, creating concern about cardiac risk of their sexual activity, and their therapeutic use of sildenafil. Relatively little information exists about sildenafil effects on exercise testing, hemodynamic parameters or on occurrence of ventricular arrhythmias during normal activities in ...
AkalIn Figen - - 2003
BACKGROUND: Bronchiectasis is still a widespread disease in developing countries. It is an important cause of mortality and morbidity. The information on cardiac involvement in bronchiectasis is limited. However, cor pulmonale is common in patients with chronic lung disease, such as cystic fibrosis. METHODS: We utilized echocardiography and exercise tests, ...
Frolkis Joseph P - - 2003
BACKGROUND: Exercise-induced ventricular ectopy predicts an increased risk of death in population-based cohorts. We sought to examine in a clinical cohort the prognostic importance of ventricular ectopy immediately after exercise, when reactivation of parasympathetic activity occurs. We hypothesized that ventricular ectopy after exercise (i.e., during the recovery phase) would predict ...
Dawson Ellen - - 2003
A reduction in left ventricular systolic and diastolic function subsequent to prolonged exercise in healthy humans, often called exercise-induced cardiac fatigue (EICF), has recently been reported in the literature. However, our current understanding of the exact nature and magnitude of EICF is limited. To date, there is no consensus as ...
Titcomb Clifton P CP - - 2003
Frequently an underwriter or medical director will question whether an increase in left ventricular mass represents pathologic left ventricular hypertrophy (LVH) or physiologic changes related to exercise. The LVH condition reflects end-organ damage related to abnormal hemodynamic stresses and confers an increased morbidity and mortality risk. When left ventricular mass ...
Park Sang-Kab - - 2003
The purpose of this study was to investigate the changes of maximal oxygen consumption, left ventricular function and serum lipids after 36 weeks of aerobic exercise in elderly women without the influence of drugs. Eight elderly women were studied by M-mode and Doppler echocardiography to assess left ventricular size, mass ...
Partington Sara - - 2003
OBJECTIVE: The purpose of this study was to determine the prevalence and prognostic significance of exercise-induced ventricular arrhythmias (EIVAs) in patients referred for exercise testing, considering the arrhythmic substrate and exercise-induced ischemia. BACKGROUND: EIVAs are frequently observed during exercise testing, but their prognostic significance is uncertain. The design of this ...
Nottin Stéphane - - 2002
A transient increase in left ventricular emptying has been reported in adults during the early recovery from submaximal upright exercise. PURPOSE: To investigate whether this "overshoot" occurs also after maximal exercise, and whether it is an age-related phenomenon. METHODS: Ten healthy young men (mean age: 22.5 +/- 1.5 yr) and ...
de Leon M J - - 2002
Cross-sectional cerebrospinal fluid (CSF) levels of tau and amyloid (A) beta (beta) are of diagnostic importance for Alzheimer's disease (AD) and mild cognitive impairment (MCI). However, most longitudinal studies of tau fail to demonstrate progression. Because predominantly brain-derived proteins such as tau, have higher ventricle to lumbar ratios, we hypothesized ...
Gates Phillip E - - 2003
Upper body exercise has many applications to the rehabilitation and maintenance of cardiovascular health of individuals who are unable to exercise their lower body. The hemodynamic loads of upper body aerobic exercise are characterized by relatively high blood pressure and relatively low venous return. It is not clear how the ...
Ochiai Yoshie - - 2002
BACKGROUND: Insertion of an implantable left ventricular assist device (LVAD) complicated by early right ventricular (RV) failure has a poor prognosis and is largely unpredictable. Prediction of RV failure after LVAD placement would lead to more precise patient selection and optimal device selection. METHODS AND RESULTS: We reviewed data from ...
Sagiv Michael - - 2002
BACKGROUND: In previous studies, the effect of isometric stress on the dynamic performance of a graded exercise test in normal subjects augmented afterload and brought about changes in left ventricular function more often than did results from physical exercise. OBJECTIVE: This study used the metabolic charts and echocardiography to examine ...
Hainsey Tess - - 2002
Cyclosporin A (CsA) has been shown to inhibit pathophysiological models of overload-induced cardiac hypertrophy, indicating a role for the calcium dependent signal pathways. It is unclear what impact CsA may have on the myocardial response to exercise, a physiological model of overload.PURPOSE: The purpose of the study was to determine ...
Li Yang - - 2002
The effects of benzyltetrahydropalmatine (BTHP), a new class III antiarrhythmic agent, on the action potential in guinea pig papillary muscle and the rapidly activating component (I(Kr)) and the slowly activating component (I(Ks)) of the delayed rectifier potassium current (I(K)) in isolated guinea pig ventricular myocytes were investigated. The action potentials ...
Nottin S - - 2002
Stroke volume (SV) response to exercise depends on changes in cardiac filling, intrinsic myocardial contractility and left ventricular afterload. The aim of the present study was to identify whether these variables are influenced by endurance training in pre-pubertal children during a maximal cycle test. SV, cardiac output (Doppler echocardiography), left ...
Mitchell Brett M - - 2002
OBJECTIVE: Little is known about the relations of fitness and fatness to left ventricular structure and function in obese adolescents. This project had 2 purposes: 1) to determine the correlations of cardiovascular fitness and adiposity to left ventricular parameters in obese adolescents; and 2) to see the effect of 8 ...
Batchvarov Velislav - - 2002
BACKGROUND: Total R T cosine (TCRT) is a new descriptor of repolarization heterogeneity that quantifies the deviation between the directions of ventricular depolarization and repolarization. It revives the old concept of ventricular gradient (VG). HYPOTHESIS: Our goal was to examine whether TCRT and VG contain nonredundant information by comparing their ...
Sleeper Margaret M - - 2002
PURPOSE: Chronic administration of pharmacological levels of beta2-agonists have been shown to have toxic effects on the heart; however, no data exist on cardiac function after chronic clenbuterol administration. The purpose of this study was to examine the effect of therapeutic levels of clenbuterol on cardiac performance. METHODS: Twenty unfit ...
Rowland Thomas - - 2002
PURPOSE: The purpose of this study was to compare cardiac physiological and dimensional responses to exercise in highly trained young male cyclists (mean age 13.7 +/- 1.0 yr) with those of nontrained boys. METHODS: Ventricular systolic and diastolic dimensions were measured by two-dimensional echocardiography, and stroke volume was estimated by ...
Gambliel Herve A - - 2002
Chronic anthracycline administration to rabbits causes impairment of cardiac contractility and decreased gene expression of the calcium-induced calcium release channel of sarcoplasmic reticulum (SR), the ryanodine receptor (RYR2). The C-13 hydroxy metabolite (doxorubicinol), formed in the heart, has been hypothesized to contribute to anthracycline cardiotoxicity. C-13 deoxydoxorubicin is an analog ...
Jamshidi Yalda - - 2002
BACKGROUND: Left ventricular hypertrophy (LVH) occurs as an adaptive response to a physiological (such as exercise) or pathological (valvular disease, hypertension, or obesity) increase in cardiac work. The molecular mechanisms regulating the LVH response are poorly understood. However, inherited defects in fatty acid oxidation are known to cause severe early-onset ...
Leung, Dominic Y. C.
The projects of this thesis examine the complex interaction between isotonic exercise, functional capacity, exercise-induced myocardial ischaemia, severity of regurgitation and left ventricular function in patients with significant chronic mitral regurgitation. The concept of left ventricular contractile reserve, i.e. the ability of the left ventricle to increase its contractility and ...
Shi, Jian Rong
The aim of the study was to examine the effects of a long-term endurance-training on resting and exercising cardiac responses on male adolescents. The sample consisted of 13 endurance-trained and 7 non-athletic male adolescents (x ± SE, age = 15.33 ± 0.33 and 15.15 ± 0.23 years, respectively). The volunteers ...
Linneweber J - - 2001
An implantable biventricular assist device (BVAD) has been developed at Baylor College of Medicine using 2 centrifugal blood pumps. The aim of this study was to investigate the exercise-reflex response during nonpulsatile biventricular assistance and to evaluate to which degree the autoregulation of the system would accommodate the changed hemodynamic ...
Gemayel C - - 2001
Arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC) is a cardiomyopathy characterized pathologically by fibrofatty replacement primarily of the RV and clinically by life-threatening ventricular arrhythmias in apparently healthy young people. The prevalence of the disease has been estimated at 1 in 5,000 individuals, although this estimate will likely increase as awareness ...
Hauser M - - 2001
Anthracyclines are used in the therapy of several of the most common paediatric oncological disorders. The usefulness of these agents is limited by cardiotoxicity, with congestive heart failure developing in up to 20% of patients. To stratify possible risk factors, we investigated 38 children with acute lymphoblastic leukaemia for signs ...
Bustillo J R - - 2001
N-Acetyl-aspartate (NAA), a marker of neuronal integrity, has been found to be reduced in frontal regions in schizophrenia. However, the impact of antipsychotic drug type on NAA has not been carefully evaluated. We studied outpatients with schizophrenia/schizoaffective disorders chronically treated with haloperidol or clozapine and normal controls with single-voxel 1H-MRS ...
Wisløff U - - 2001
INTRODUCTION: A novel hypothesis for increased ventricular pumping describes the heart as a displacement pump, in which atrioventricular plane displacement (AVPD) is an important mechanism. The hypothesis predicts that AVPD increases at high heart rates. The aim of the present study was to determine whether AVPD increases during exercise at ...
Chen J - - 2001
1. Previous work demonstrating that DA inbred rats are superior to COP inbred rats in aerobic treadmill running capacity has indicated their utility as genetic models to explore this trait. We tested the general hypothesis that intermediate phenotypes of cardiac function and calcium metabolism are responsible for the difference in ...
Kepski R - - 2001
The application of adaptive filtering to ECG signals has been investigated for many years. This study shows that the exercise high resolution ECG (HRECG) can also be processed successfully in a similar way. Two groups were included consisting of 20 healthy individuals and 24 patients with hypertrophic cardiomyopathy (HCM). The ...
Palatini P - - 2001
The aim of the present study was to assess how cardiac structural changes contribute to increasing left ventricular pump function during exercise in subjects with mild hypertension. In 23 young male subjects with mild hypertension and 12 male normotensive control subjects, left ventricular function was measured echocardiographically using the fractional ...
Holmgren D - - 2001
A 2-y-old boy with scimitar syndrome underwent surgery involving the redirection of partial anomalous pulmonary venous return to the left atrium. Heart catheterization after the operation did not reveal any significant intra-cardiac shunts. An exercise test performed at the age of 10 y revealed a reduction in working capacity. At ...
Miyashita T - - 2001
BACKGROUND: It is known that left ventricular systolic function at rest does not correlate well with exercise capacity of patients with heart failure. However, the contribution of left ventricular diastolic dysfunction, especially during exercise, to exercise capacity of cardiac patients remains to be determined. OBJECTIVE: To determine the impact of ...
Axelsson M - - 2001
The foramen of Panizza is located within the outflow tract of the crocodilian heart, between the left and right aortas. It has been suggested that the foramen of Panizza has a variable calibre, which could explain the profound changes in the distribution of flows and pressure profiles recorded in the ...
Wieselthaler G M - - 2001
As known from patients with pulsatile ventricular assist devices (VADs), early mobilization, physical exercise, and return to normal life are essential for optimal recovery. Recently, implantable rotary pumps became available for extended left ventricular support as bridges to transplantation. Modified procedures are essential for patient training and hospital discharge. The ...
Firoozi S - - 2001
Hypertrophic cardiomyopathy (HCM) is a genetic disease of the sarcomeric contractile proteins that is characterized by left ventricular hypertrophy and myocyte disarray. The majority of patients are limited in terms of functional capacity and a minority die suddenly. The main aims of management are symptom alleviation and prevention of sudden ...
1 2 3 4 5 6 7 8 9 10 >