Search results for "HEMODYNAMICS"
showing 10 items of 511 documents
Protective effect of N-acetylcysteine on ischaemia-induced myocardial damage in canine heart.
1991
The glutathione redox pathway is an important antioxidant system in the myocardium. N-Acetylcysteine is a low molecular weight glutathione precursor that has been used clinically to replenish glutathione stores. The present study was aimed at evaluating the protective effect of N-acetylcysteine on myocardial damage resulting from permanent coronary occlusion (without reperfusion) in anaesthetized dogs. N-Acetylcysteine (150 mg kg−1 i.v.) administered 2 min before occlusion rerduced infarct size in dogs subjected to 24 h ischemia. The infarct size as a percentage of the area at risk was 86.8 ± 3.6% (n = 11) in control (salinetreated) dogs and 68.2 ± 2.4% (n = 7; P < 0.05 vs control) in N-ace…
Positional brain ischemia with MCA occlusion successfully treated with extra-intracranial bypass.
2010
408 Positional cerebral ischemia (PCI) is an extremely rare condition in which dramatic central nervous system deficits are triggered by standing in patients with severe stenosis or occlusion of the major brain-supplying blood vessels [1] . Because PCI is generally associated with orthostatic hypotension [2, 3] , a hemodynamic mechanism has been proposed [4] . However, PCI has been reported even in patients without orthostatic hypotension [1] . The treatment is medical, but surgery can be considered in refractory cases (endarterectomy for carotid artery stenosis or either highor low-flow extra-intracranial bypass – for carotid occlusion) [3] . We report a case of PCI associated with middle …
Pulmonary effects of expiratory-assisted small-lumen ventilation during upper airway obstruction in pigs
2015
Summary Novel devices for small-lumen ventilation may enable effective inspiration and expiratory ventilation assistance despite airway obstruction. In this study, we investigated a porcine model of complete upper airway obstruction. After ethical approval, we randomly assigned 13 anaesthetised pigs either to small-lumen ventilation following airway obstruction (n = 8) for 30 min, or to volume-controlled ventilation (sham setting, n = 5). Small-lumen ventilation enabled adequate gas exchange over 30 min. One animal died as a result of a tension pneumothorax in this setting. Redistribution of ventilation from dorsal to central compartments and significant impairment of the distribution of ve…
Coronary artery fistulas as a cause of angina: How to manage these patients?
2015
Abstract Coronary artery fistulas represent the most common hemodynamically significant congenital defect of the coronary arteries and the clinical presentation is mainly dependent on the severity of the left-to-right shunt. We describe a case of a 55-year-old man with history of chest pain and without history of previous significant chest wall trauma or any invasive cardiac procedures. A coronary multislice computed tomography showed two large coronary fistulas arising from the left anterior descending coronary artery and ending in an angiomatous plexus draining into the common pulmonary trunk. Coronary angiography confirmed the CT finding and showed a third fistulous communication arising…
Diagnostic performance of whole brain volume perfusion CT in intra-axial brain tumors: preoperative classification accuracy and histopathologic corre…
2012
Abstract Background To evaluate the preoperative diagnostic power and classification accuracy of perfusion parameters derived from whole brain volume perfusion CT (VPCT) in patients with cerebral tumors. Methods Sixty-three patients (31 male, 32 female; mean age 55.6 ± 13.9 years), with MRI findings suspected of cerebral lesions, underwent VPCT. Two readers independently evaluated VPCT data. Volumes of interest (VOIs) were marked circumscript around the tumor according to maximum intensity projection volumes, and then mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability Ktrans perfusion datasets. A second VOI was placed in the contra lateral cortex, as cont…
Effects of Cortical Spreading Depression on Cortical Blood Flow, Impedance, DC Potential, and Infarct Size in a Rat Venous Infarct Model
2000
A cortical venous infarction model has been evaluated as to the degree of regional flow reduction and by studying effects of cortical spreading depression (CSD). Two adjacent cortical veins were occluded photochemically with rose bengal and fiberoptic illumination. Seven rats served to demonstrate effects on regional cortical blood flow using laser Doppler scanning. In 36 rats local CBF, DC potential, and brain tissue impedance were measured continuously for 75 min after vein occlusion. No, 3, or 10 CSD waves were induced by potassium chloride injection during the initial 75 min. Rats were compared for spontaneous CSDs; baseline local CBF, CBF, and impedance response to CSD; and infarct vol…
Benfotiamine accelerates the healing of ischaemic diabetic limbs in mice through protein kinase B/Akt-mediated potentiation of angiogenesis and inhib…
2006
Benfotiamine, a vitamin B1 analogue, reportedly prevents diabetic microangiopathy. The aim of this study was to evaluate whether benfotiamine is of benefit in reparative neovascularisation using a type I diabetes model of hindlimb ischaemia. We also investigated the involvement of protein kinase B (PKB)/Akt in the therapeutic effects of benfotiamine. Streptozotocin-induced diabetic mice, given oral benfotiamine or vehicle, were subjected to unilateral limb ischaemia. Reparative neovascularisation was analysed by histology. The expression of Nos3 and Casp3 was evaluated by real-time PCR, and the activation state of PKB/Akt was assessed by western blot analysis and immunohistochemistry. The f…
Effects of Steatosis on Hepatic Hemodynamics in Patients with Metabolic Syndrome
2015
The aim of our study was to assess the hemodynamic changes in hepatic and splenic circulation using B-mode ultrasonography and color Doppler ultrasonography, in a population of patients with metabolic syndrome divided with respect to the presence or absence of steatosis diagnosed by ultrasonography. One hundred forty-one patients were included in the study. The severity of non-alcoholic fatty liver disease was classified as mild, moderate or severe. Visceral fat thickness, longitudinal diameter of the spleen, diameter of the portal vein, mean maximum portal vein flow velocity, hepatic artery and splenic artery resistivity indexes and hepatic vein flow phasicity were measured. Non-alcoholic …
Plasma Renin Concentration is Associated With Hemodynamic Deficiency and Adverse Renal Outcome in Septic Shock.
2019
International audience; Background: In septic shock, both systemic vasodilatation and glomerular arteriole dilatation are responsible for the drop in glomerular filtration observed in early acute kidney injury. Angiotensin II has been showed to act on both mechanisms. Our objective was to evaluate the impact of renin angiotensin system activation, on hemodynamic deficiency and renal outcome in patient with septic shock and to assess whether urinary sodium could be a reliable test for high plasma renin concentration screening.Methods: This was a prospective and observational study. Inclusion criteria were 1) early septic shock (first episode) 2) dose of norepinephrine ≥ 0.25 μg/kg/min 3) bef…
Obesity related changes in cardiac structure and function: role of blood pressure and metabolic abnormalities.
2019
BACKGROUND: It has been reported that changes in cardiac structure and ventricular function associated with obesity have to be attributable to hemodynamic and non-hemodynamic alterations. Accordingly, the aim of this was to evaluate left ventricular hypertrophy (LVH) prevalence and its effect on left ventricular systolic and diastolic function in a cohort of obese patients. MATERIALS AND METHODS: LV internal diameter (LVID), left ventricular mass (LVM) and LVM/height2.7(LVMI), relative wall thickness (RWT), LV ejection fraction (LVEF), E/A ratio, isovolumic relaxation time, deceleration time of E velocity by echocardiography and pulsed-wave Doppler and total circulating adiponectin (ADPN) b…