Search results for "Circulation"
showing 10 items of 1137 documents
Lack of association between carotid artery volume blood flow and cardiac output.
2001
Objective. The correlation of cardiac output and cerebral perfusion is unclear. We tested this potential association by correlating cardiac output data obtained by echocardiography and cerebral blood flow data as determined by color M-mode measurements of carotid artery blood flow. Methods. We studied 43 patients with a broad spectrum of cardiac performance by means of transthoracic echocardiography. In these patients, different cardiac indices such as stroke volume, ejection fraction, and heart minute volume were determined. The data were correlated with volumetric flow measurements (color M-mode duplex system) of the common carotid arteries bilaterally. Results. Heart minute volume ranged…
The influence of Albunex on the pulmonary circulation in patients with pulmonary hypertension or left heart failure.
1996
To determine the safety of the ultrasound contrast agent Albunex, its influence on right and left heart haemodynamics in patients with pulmonary artery hypertension or left heart failure was assessed after intravenous injection. Patients with a left ventricular ejection fraction smaller than 40% or a systolic pulmonary artery pressure greater than 40 mmHg received 0.08 and 0.22 ml.kg -1 Albunex and 10 ml albumin in random order during right heart catheterization and transthoracic echocardiography. Right atrial, systolic and diastolic pulmonary artery and capillary wedge pressures were measured at 3 min and 5 min and cardiac output at 5 min after the intravenous injection of Albunex and cont…
Effects of levosimendan on hemodynamics, local cerebral blood flow, neuronal injury, and neuroinflammation after asphyctic cardiac arrest in rats.
2014
Despite advances in cardiac arrest treatment, high mortality and morbidity rates after successful cardiopulmonary resuscitation are still a major clinical relevant problem. The post cardiac arrest syndrome subsumes myocardial dysfunction, impaired microcirculation, systemic inflammatory response, and neurological impairment. The calcium-sensitizer levosimendan was able to improve myocardial function and initial resuscitation success after experimental cardiac arrest/cardiopulmonary resuscitation. We hypothesized that levosimendan exerts beneficial effects on cerebral blood flow, neuronal injury, neurological outcome, and inflammation 24 hours after experimental cardiac arrest/cardiopulmonar…
Extracranial internal carotid artery occlusion: the role of common carotid artery volume flow.
2002
BACKGROUND AND PURPOSE Quantitative measurement of blood flow volume in the common carotid artery (CCA) is now possible using the color velocity imaging quantification (CVI-Q) ultrasound technique. The aim of this study was to evaluate the cerebral hemodynamic effects of unilateral internal carotid artery (ICA) occlusion on CCA blood flow volumes (FVs) using CVI-Q. METHODS Records of ultrasound studies in our neurosonology laboratory were retrospectively reviewed to identify patients with unilateral ICA occlusions who at a minimum received both a routine color duplex carotid ultrasound examination and quantitative measurement of FV in the CCA, bilaterally, using the CVI-Q method. A total of…
A new model of thromboembolic stroke in the posterior circulation of the rat
2006
The prognosis of vertebrobasilar occlusion is grave and therapeutic options are limited. The aim of the present study was to develop a new model of embolic hindbrain ischemia in the rat that closely resembles the clinical situation and that can be used to study pathophysiology and treatment options. After thoracotomy in 20 male Wistar rats, 15 animals received an injection of in vitro prepared autologous blood clots into the left vertebral artery. Five animals without clot injection served as controls. Neurological deficits were assessed in all animals 2 h after embolism. After 2 h, five animals were sacrificed to measure cerebral blood flow (CBF) by iodo-antipyridine autoradiography, and t…
CXCR2 blockade impairs angiotensin II-induced CC chemokine synthesis and mononuclear leukocyte infiltration.
2007
Objective—Angiotensin II (Ang-II) and mononuclear leukocytes are involved in atherosclerosis. This study reports the inhibition of Ang-II–induced mononuclear cell recruitment by CXCR2 antagonism and the mechanisms involved.Methods and Results—Ang-II (1 nmol/L, i.p. in rats) induced CXC and CC chemokines, followed by neutrophil and mononuclear cell recruitment. Administration of the CXCR2 antagonist, SB-517785-M, inhibited the infiltration of both neutrophils (98%) and mononuclear cells (60%). SB-517785-M had no effect on the increase in CXC chemokine levels but reduced MCP-1, RANTES, and MIP-1α release by 66%, 63%, and 80%, respectively. Intravital microscopy showed that pretreatment with S…
Arrhythmias and inhibition of noradrenaline uptake caused by tricyclic antidepressants and chlorpromazine on the isolated perfused rabbit heart
1975
1. Isolated rabbit hearts were perfused with a modified Tyrode solution containing noradrenaline in concentrations increasing stepwise from 5.9 nM to 5.9 μM at 5 min intervals. This dose regime was applied twice before and once 20 min after starting perfusion with one of 9 tricyclic drugs. Ventricular rate and right atrial and ventricular tensions were recorded using the transverse method. 2. Infusions of noradrenaline evoked ventricular arrhythmias in hearts perfused with amitriptyline 4.8 μM, chlorpromazine 5.0 μM, desipramine 5.0 μM, dibenzepine 34.7 μM, doxepin 4.7 μM, imipramine 4.7 μM, noxiptiline 9.1 μM and opipramole 9.2 μM. The incidence of arrhythmias increased with the concentrat…
Disturbance of hepatic and intestinal microcirculation in experimental liver cirrhosis
2005
AIM: To analyze hepatic, mesenteric and mucosal microcirculation and leukocyte-endothelium interaction (LEI) in a rat model with liver cirrhosis. METHODS: Hepatic cirrhosis was induced in Wistar rats by gavage with carbon tetrachloride, and intravital videomicroscopy was performed in liver, mesentery and small intestine mucosa. Special emphasis is given on microcirculatory and morphometric changes during cirrhotic portal hypertension. RESULTS: LEI was influenced significantly in the cirrhotic liver but not in the gut. Blood flow measurement showed significant differences among liver, main mesenteric vessels and the mucosa. The results of our study indicate that liver cirrhosis leads to alte…
Analysis of myocardial perfusion or myocardial function for detection of regional myocardial abnormalities. An echocardiographic multicenter comparis…
2007
Background: Echocardiography based myocardial perfusion imaging and regional wall motion analysis are used for evaluation of coronary artery disease and regional myocardial abnormalities. Aim: This study sought to compare myocardial contrast echocardiography (MCE) and 2D echocardiography with regard to interobserver variability and detection of regional myocardial abnormalities. Methods: In 70 patients evenly distributed between three ejection fraction groups based on biplane cineventriculography (>55%, 35-55%, <35%), unenhanced and contrast enhanced 2D echocardiography and myocardial contrast echocardiography (MCE; SonoVue (R); Bracco) were performed. Regional watt motion and myocardial pe…
The association between coronary microvascular dysfunction and carotid intima media thickness in patients with cardiac syndrome X
2016
Abstract Objective The aim of this study was to evaluate in patients with cardiac syndrome X (CSX), using validated angiography indices, coronary blood flow and myocardial perfusion of the microcirculation to assess whether there is greater microvascular dysfunction in patients with increase of carotid intima media thickness (C-IMT), compared to those who do not have. Methods Our study was performed on a population 124 patients with CSX that underwent coronary angiography and carotid ultrasound. We divided the sample into two categories: patients with increase of C-IMT and those without increase. We calculated Gibson and Yusuf indices for each patient based on angiographic images, including…