Search Results
Results 301 - 350 of 1326
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Gunkel Cornelia I - - 2004
A mature horse developed acute signs of bronchoconstriction causing hypoxemia and hypercapnia during anesthesia for computerized tomography of the maxillary sinus after i.v. administration of diatrizoate contrast medium. The horse was treated with aerosolized albuterol, atropine, and oxygen insufflation and recovered uneventfully despite severe hypoxemia and low hemoglobin saturation. The ...
Spahn Donat R - - 2004
Transfusion guidelines in patients with coexisting cardiac diseases are similar to the ones in patients without such comorbidity, in that allogeneic blood transfusions most often are indicated at hemoglobin levels of less than 6.0 g/dL and hardly ever at hemoglobin levels greater than 10 g/dL. In the hemoglobin range of ...
Gatsura S V - - 2004
The mechanism of antiischemic effect of low-energy laser radiation was studied in rats with experimental myocardial infarction taking into consideration the effect of laser on hemoglobin affinity for oxygen and intensity of lipid peroxidation. Low-energy laser irradiation for 15 min in vitro decreased the area of myocardial infarction, slightly reduced ...
Harper S L - - 2004
The cardiovascular system is the first system to become functional in a developing animal and must perform key physiological functions even as it develops and grows. The ontogeny of cardiac physiology was studied throughout embryonic and larval developmental stages in the red swamp crayfish Procambarus clarkii using videomicroscopic dimensional analysis. ...
Ilangovan Govindasamy - - 2004
Oxygen plays a critical role in the pathophysiology of myocardial injury during both ischemia and subsequent reperfusion (I/R). Thus, oxygen concentration is an important variable to measure during I/R. In the present work, electron paramagnetic resonance (EPR)-based oximetry was used to measure the oxygen concentration during a series of I/R ...
Monnet X - - 2004
Initially described more than 30 years ago, the Pulmonary Artery Catheter (PAC) technique was becoming more and more used in the following years. This hemodynamic monitoring device can be used according 2 different therapeutic attitudes. The first one strives to achieve supranormal hemodynamic values, particularly in terms of cardiac index ...
Lloyd Steven G - - 2004
Interventions that stimulate carbohydrate oxidation appear to be beneficial in the setting of myocardial ischemia or infarction. However, the mechanisms underlying this protective effect have not been defined, in part because of our limited understanding of substrate utilization under ischemic conditions. Therefore, we used (1)H and (13)C NMR spectroscopy to ...
Kurzelewski M - - 2004
Evidence indicates that nitric oxide (NO) suppresses myocardial oxygen consumption (MVO(2)) and regulates myocardial substrate oxidation, however data from in vivo and isolated heart preparations are conflicting. In addition, cardiac endothelin (ET-1) release has been shown to increase with inhibition of NO synthase (NOS), however the effects of ET-1 on ...
Ibáñez Borja B Servicio de Cardiología, Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Madrid, - - 2004
Tako-tsubo-like transient left ventricular apical ballooning has been described in Japan, but few cases have been reported in Western countries. We report one of the first series outside Japan, which provides new information on the coronary anatomy of this disorder. From January 1998 to February 2003 we observed 11 patients ...
Ivnitski-Steele Irena D - - 2004
BACKGROUND: Previous research has demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces cardiomyocyte growth arrest, thinner ventricle walls, and reduced number and size of coronary arteries during chick embryogenesis. Coronary vascular development is believed to be mediated, in part, by myocardial oxygen gradients and a subsequent increase in hypoxia-inducible factor 1alpha (HIF-1alpha) and ...
Mital Seema - - 2004
BACKGROUND: Nitric oxide (NO) binds to mitochondrial cytochrome oxidase to decrease myocardial oxygen consumption (MVO(2)). This regulation is disrupted in heart failure (HF) due to reduced NO. The present objective was to evaluate NO-mediated regulation of mitochondrial respiration in the myocardium of patients with congenital heart disease (CHD) and cardiomyopathy ...
Frøbert Ole - - 2004
Low O2 tension dilates coronary arteries and high O2 tension is a coronary vasoconstrictor but reports on O2-dependent effects on ventricular performance diverge. Yet oxygen supplementation remains first line treatment in cardiovascular disease. We hypothesized that hypoxia improves and hyperoxia worsens myocardial performance. Seven male volunteers (mean age 38 +/- ...
Body Richard - - 2004
A short cut review was carried out to establish whether supplemental oxygen reduces mortality in patients with uncomplicated acute myocardial infarction. Altogether 290 papers were found using the reported search, of which one presented the best evidence to answer the clinical question. The author, date and country of publication, patient ...
Barriales Villa Roberto R Servicio de Cardiología, Complexo Hospitalario de Pontevedra, Pontevedra, - - 2004
A syndrome of transient apical ballooning without coronary stenosis, which mimics acute myocardial infarction, was recently described. Although several possible etiologic mechanisms have been proposed and investigated, the precise cause remains unclear. We describe 3 cases of transient left ventricular apical ballooning without coronary stenosis, and discuss the etiology of ...
DeWall Richard A - - 2003
Open heart surgery was not possible before the early 1950s. The development of controlled cross-circulation at the University of Minnesota in 1953 was a major contributing factor toward operating safely on the interior of the heart. Cross-circulation required connecting a donor's arterial and venous blood vessels to those of a ...
Tossios Paschalis - - 2003
OBJECTIVE: Reactive oxygen species have been shown to contribute to myocardial stress in patients undergoing cardiac surgery, as demonstrated by myocardial 8-iso-prostaglandin-F(2)alpha and nitrotyrosine formation. We hypothesized that the reactive oxygen species scavenger N-acetylcysteine attenuates reactive oxygen species-mediated myocardial stress in patients undergoing cardiac surgery. METHODS: Forty patients undergoing coronary ...
Kounis N G NG School of Health, Patras Highest Institute of Education and Technolgy, Patras, Greece. - - 2003
Cardiorespiratory complications may occur during gastrointestinal endoscopy, and elderly people seem to be more vulnerable to these complications during endoscopic procedures involving the manipulation of abdominal viscera. To determine the incidence of cardiac arrhythmias, changes in oxygen saturation, heart rate and blood pressure during endoscopic retrograde cholangiopancreatography (ERCP) via Holter ...
Schiffmann Holger - - 2003
Na+-channel modulators exert their positive inotropic action without affecting the adenylate-cyclase pathway by an increase in the open probability of the sarcolemmal Na+ channels. Although inotropic effects in neonatal hearts are less pronounced compared with adult hearts, the Na+-channel modulator BDF 9148 increases contractility and relaxation velocity in immature myocardium. ...
Gibbs Colin L - - 2003
1. The background to current ideas in cardiac energetics is outlined and, in the genomic era, the need is stressed for detailed knowledge of mouse heart mechanics and energetics. 2. The mouse heart is clearly different to the rat in terms of its excitation-contraction (EC) coupling and the common assumption ...
Kuniyoshi Yukio - - 2003
OBJECTIVE: To evaluate the effect of systemic temperature on myocardial protection during extracorporeal circulation, we quantitatively evaluated the relationship between myocardial oxygen consumption and rectal temperature. MATERIALS AND METHODS: Myocardial oxygen consumption during cardiac arrest was calculated via blood gas analysis of venous blood samples collected from the coronary sinus. ...
Gorman Des - - 2003
Carbon monoxide (CO) is a dangerous exogenous poison and an essential endogenous neurotransmitter. This gas when inhaled has an anaesthetic effect, which is poorly understood, but which may be fatal if compensatory mechanisms are exhausted, if cardiac oxygen (O(2)) needs exceed myocardial oxygenation and/or if apnoea or asphyxia onsets. Although ...
Vanhanen Ingemar - - 2003
OBJECTIVE: To study cardiac uptake and release of substrates and the influence of intravenous glutamate in patients operated for unstable angina requiring intravenous nitrates. DESIGN: Nineteen patients were randomized to blinded infusion of glutamate or saline. Arterial-coronary sinus differences of substrates were measured before cardiopulmonary bypass (CPB) and during early ...
Martin Claus - - 2003
Nitric oxide (NO) is involved in the control of myocardial metabolism. In normoperfused myocardium, NO synthase inhibition shifts myocardial metabolism from free fatty acid (FFA) toward carbohydrate utilization. Ischemic myocardium is characterized by a similar shift toward preferential carbohydrate utilization, although NO synthesis is increased. The importance of NO for ...
Carvajal Karla - - 2003
Myocardial function depends on adenosine triphosphate (ATP) supplied by oxidation of several substrates. In the adult heart, this energy is obtained primarily from fatty acid oxidation through oxidative phosphorylation. However, the energy source may change depending on several factors such as substrate availability, energy demands, oxygen supply, and metabolic condition ...
Peterson Linda R - - 2003
OBJECTIVES: Our aim was to determine the effect of beta-adrenergic blockade on the prognostic value of peak oxygen consumption testing in patients with heart failure. BACKGROUND: Peak oxygen consumption has been shown to be a useful prognostic tool in patients with heart failure. However, studies demonstrating the utility of peak ...
Rosenstrauch Doreen - - 2003
One possible way to expand the human heart donor pool is to include non-heart-beating human donors. To begin validating this approach, we developed an ex vivo cardiac perfusion circuit to support large mammalian hearts in Langendorff mode and beating-ejecting mode and to assess and improve their ischemic tolerance. In vivo ...
Thompson Loren P - - 2003
This review examines the effect of high altitude and/or chronic hypoxia on cardiac mechanisms that influence perfusion of the fetal heart (e.g., tissue metabolism, coronary vessel growth, and coronary blood flow and vessel responsiveness). In response to intrauterine hypoxia, the fetal heart may either reduce its energy demand or increase ...
Fredriksen Per Morten - - 2002
BACKGROUND: We investigated the aerobic capacity of 168 adult patients who had undergone successful surgical repair of retralogy of Fallot at the University of Toronto Congenital Cardiac Centre for Adults. METHODS: We compared values of peak uptake of oxygen, peak heart rate, forced vital capacity, and forced expiratory volume in ...
Coetzee Andre - - 2002
OBJECTIVE: To examine the effect of acebutolol, a beta-adrenergic-receptor blocker, on severe regional myocardial ischemia, specifically the effects on regional myocardial function and metabolism. DESIGN: Randomized study. SETTING: Animal laboratory of the Department of Anesthesiology and Critical Care, University of Stellenbosch Medical School. PARTICIPANTS: Anesthetized open-chest pig model (n = ...
Perko Mario J - - 2002
The aim of the study was to assess changes in myocardial oxygenation in patients with ischaemic heart disease during surgical revascularisation. In 20 patients, regional oxygen saturation, oxyhaemoglobin and total haemoglobin concentrations were examined by near-infrared spectroscopy in the myocardium and in a non-ischaemic skeletal muscle, which served as a ...
Himpe D G - - 2002
BACKGROUND AND OBJECTIVE: The effects of administering albumin 5%, hydroxyethylstarch 6% and succinylated gelatine 4% on oxygen transport and left ventricular function were prospectively investigated in different experimental conditions: baseline, fluid load, after 10 min of myocardial ischaemia and after reperfusion. METHODS: Twenty-seven rabbits received at random one of three ...
Kawaguchi Osamu - - 2002
BACKGROUND: This study investigates the possibility of reducing myocardial oxygen consumption by dynamic cardiomyoplasty in chronic heart failure. The sheep model used is relevant for cardiac assist using direct mechanical cardiac compression. METHODS: In 7 sheep, heart failure was induced by staged intracoronary microembolization followed by dynamic cardiomyoplasty. Six months ...
Bosenberg Craig - - 2002
The heart plays a pivotal role in determining the oxygen supply to the body. As a result of its high oxygen extraction ratio, the myocardium must function efficiently to supply itself with oxygen. In the context of the ICU, the efficient functioning of the myocardium is confounded by a number ...
Linke Axel - - 2002
We assessed whether pregnancy results in enhanced nitric oxide (NO)-mediated control of myocardial oxygen consumption. Rats were studied before (C), at 1 wk (1w) or 2 wk (2w) of pregnancy, and at 4 days after giving birth (-4d). Left ventricular endothelial NO synthase (eNOS) protein expression was determined by immunoblotting. ...
Des Tombe A L - - 2002
Oxygen supply and demand of individual cardiomyocytes during the development of myocardial hypertrophy is studied using calibrated histochemical methods. An oxygen diffusion model is used to calculate the critical extracellular oxygen tension (PO(2,crit)) required by cardiomyocytes to prevent hypoxia during hypertrophic growth, and determinants of PO(2,crit) are estimated using calibrated ...
Shiga Toshiya - - 2002
Transesophageal echocardiography (TEE) has not been used during airway manipulation to assess the occasional occurrence of hemodynamic instability that occurs especially in cardiac patients. We describe a new technique using an endoscopy mask to perform TEE monitoring during airway manipulation with a large concentration of supplemented oxygen.
D?vila-Rom?n V?ctor G - - 2002
OBJECTIVES: The purpose of this study was to determine whether patients with idiopathic dilated cardiomyopathy (IDCM) exhibit alterations in myocardial fatty acid and glucose metabolism. BACKGROUND: Alterations in myocardial metabolism have been implicated in the pathogenesis of heart failure (HF); however, studies of myocardial metabolic function in human HF have ...
Chen YingJie - - 2002
BACKGROUND: Endogenous nitric oxide (NO) has been reported to inhibit oxygen consumption in the normal heart, so that nonselective inhibition of NO synthase (NOS) caused an increase of myocardial oxygen consumption (MVO2). Although endothelial NOS responses are depressed in congestive heart failure (CHF), inducible NOS (iNOS) may be expressed in ...
Csont Tamás - - 2002
Clinical studies have suggested that long-term nitrate treatment does not improve and may even worsen cardiovascular mortality, and the possible role of nitrate tolerance has been suspected. Nitrate tolerance has been recently shown to increase vascular superoxide and peroxynitrite production leading to vascular dysfunction. Nevertheless, nitrates exert direct cardiac effects ...
Nordhaug D - - 2002
OBJECTIVE: We hypothesised that acute ischemic left ventricular failure is characterised by depressed systolic and diastolic function combined with inefficiency in oxygen to mechanical work energy transfer. METHODS: Eight anaesthetised pigs (32+/-3 kg) were employed in an in vivo open chest model. Intraventricular combined pressure and conductance catheters were used ...
Nagaya Noritoshi - - 2002
This study investigated the effects of adrenomedullin on left ventricular myocardial contraction and relaxation, coronary blood flow, and myocardial oxygen consumption in comparison with those of atrial natriuretic peptide (ANP). Fourteen patients who had had myocardial infarctions were randomly assigned to receive IV infusion of adrenomedullin (0.05 microg/kg/min) or ANP ...
Ziegler André - - 2002
Despite their prime role in maintaining contractile performance, myocardial substrate uptake, substrate preference and metabolism are difficult to assess non-invasively. The objective of the present work was to extend the scope of cardiac 13C nuclear magnetic resonance (NMR) spectroscopy to the in vivo situation ('closed-chest model') and to quantitatively appraise ...
Recchia Fabio A - - 2002
Solid experimental evidence indicates that nitric oxide (NO) inhibits oxygen utilization in vitro and in vivo. The role played by NO in cellular metabolism is likely extended to the control of substrate utilization. Studies performed in normal hearts show that NO inhibits glucose uptake and that a reduced synthesis of ...
Ingelmo P - - 2002
Increased metabolic requirements by surgical trauma is responsible of the changes in cardiac index and oxygen delivery (DO2), represent compensatory adaptation in circulatory functions stimulated by increased metabolic needs. The amount of this compensation varies with age, gender, severity of illness, operation type, associated medical conditions, shock duration, complications, organ ...
Berlin Gösta - - 2002
O(2) transport and O(2) diffusion interact in providing O(2) to tissue, but the extent to which diffusion may be critical in the heart is unclear. If O(2) diffusion limits mitochondrial oxygenation, a change in blood O(2) affinity at constant total O(2) transport should alter cardiac O(2) consumption (VO(2)) and function. ...
Barnes Edward - - 2002
OBJECTIVES: In patients with coronary artery disease (CAD), we sought to demonstrate normal myocardial blood flow (MBF) and myocardial oxygen consumption (MMRO(2)) to post-ischemic myocardium that exhibited reversible dysfunction and the relation between the severity of the dysfunction and the preceding ischemia. BACKGROUND: In animal models of stunning, MBF and ...
Salem Jennifer E - - 2002
A moderate reduction in coronary blood flow results in decreased myocardial oxygen consumption, accelerated glycolysis, decreased pyruvate oxidation, and lactate accumulation. To quantitatively understand cardiac metabolism during ischemia, we have developed a mechanistic, mathematical model based on biochemical mass balances and reaction kinetics in cardiac cells. By numerical solution of ...
Kal Jasper E - - 2002
The effect of calcium channel blockers may affect the feedback mechanism between myocardial metabolic activity and coronary blood flow. To test this hypothesis the effect of calcium channel blockade on metabolic coronary flow regulation was studied. In 10 patients with stable coronary artery disease, coronary sinus blood flow and myocardial ...
Setty Srinath - - 2002
This study was designed to test if nitric oxide (NO) contributes to norepinephrine-induced right coronary vasodilation and if NO blunts the norepinephrine-induced increase in myocardial oxygen consumption (MVO(2)) in the right ventricle. In five anesthetized, open-chest dogs, mean aortic pressure, heart rate, right ventricular rate of pressure development over time ...
Yo K Y - - 2002
BACKGROUND: Brief myocardial ischaemia has been demonstrated to result in mechanical and coronary endothelial dysfunction, in which calcium may play a role. We examined whether the mechanical and vascular responses to calcium are altered in postischaemic, reperfused myocardium. METHODS: Regional myocardial oxygen consumption (MVO2), mechanical function and coronary blood flow ...
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