Search results for "Pressure"
showing 10 items of 4493 documents
Differential contribution of dead space ventilation and low arterial pCO2 to exercise hyperpnea in patients with chronic heart failure secondary to i…
2003
In chronic heart failure (CHF), the abnormally large ventilatory response to exercise (VE/VCO(2) slope) has 2 conceptual elements: the requirement of restraining arterial partial pressure of carbon dioxide (pCO(2)) from increasing (because of an increased ratio between increased physiologic dead space and tidal volume [VD/VT]) and the depression of arterial pCO(2) by further increased ventilation, which necessarily implies an important non-carbon dioxide stimulus to ventilation. We aimed to assess the contribution of these 2 factors in determining the elevated VE/VCO(2) slope in CHF. Thirty patients with CHF underwent cardiopulmonary exercise testing (age 65 +/- 11 years, left ventricular e…
Effect of Supplemental Oxygen versus Dobutamine Administration on Liver Oxygen Tension in dPP-Guided Normovolemic Pigs
2008
<i>Background:</i> Difference in pulse pressure (dPP) confirms adequate intravascular filling as a prerequisite for tissue perfusion. We hypothesized that both oxygen and dobutamine increase liver tissue oxygen tension (pt<i>O</i><sub>2</sub>). <i>Methods:</i> Eight anesthetized pigs received dPP-guided fluid management. Hepatic p<i>O</i><sub>2</sub> was measured with Clark-type electrodes placed subcapsularly, and on the liver surface. Pigs received: (1) supplemental oxygen (F<sub>i</sub><i>O</i><sub>2</sub> 1.0); (2) dobutamine 2.5 μg/kg/min, and (3) dobutamine 5 μg/kg/min. Data wer…
Ocular Comorbidities and the Relationship between Eye Diseases and Systemic Disorders
2016
Patients with ocular disorders may have additional ophthalmic problems that can have an impact on both morbidity and vision. Ocular comorbidities are commonly associated with vision-related disability and decreased quality of life related to visual impairment. The majority of studies on this topic deal with cataracts, glaucoma, uveitis, and/or retinopathies. It is important to summarize the available evidence to date on the association of one or several ocular diseases and the implications these comorbidities have on prognosis and therapy. The relationship between eye disorders and systemic diseases has recently drawn special interest. The increasing prevalence of neurodegenerative disorder…
Pressure–volume relationship by pharmacological stress cardiovascular magnetic resonance
2021
Abstract Background. The variation between rest and peak stress end-systolic pressure-volume relation (ΔESPVR) is an index of myocardial contractility, easily obtained during routine stress echocardiography and never tested during dipyridamole stress-cardiac magnetic resonance (CMR). We assessed the ΔESPVR index in patients with known/suspected coronary artery disease (CAD) who underwent dipyridamole stress-CMR.Methods. One-hundred consecutive patients (24 females, 63.76±10.17 years) were considered. ESPVR index was evaluated at rest and stress from raw measurement of systolic arterial pressure and end-systolic volume by biplane Simpson’s method. Results. The ΔESPVR index showed a good inte…
Relationship Between Carotid Atherosclerosis and Pulse Pressure with Renal Hemodynamics in Hypertensive Patients.
2015
BACKGROUND Structural atherosclerotic damage, arterial stiffness, pulse pressure (PP), and renal hemodynamics may interact and influence each other. Renal resistance index (RRI) appears as a good indicator of systemic vascular changes. The aim of our study was to assess the independent relationships of carotid intima-media thickness (cIMT), aortic pulse wave velocity (aPWV), and peripheral PP with RRI in hypertensives with various degrees of renal function. METHODS We enrolled 463 hypertensive patients (30-70 years) with normal renal function (group 0; n = 280) and with chronic kidney disease (groups I-V; n = 183). All subjects underwent ultrasonographic examination of intrarenal and caroti…
Early Vascular Aging in Normotensive Patients With Systemic Lupus Erythematosus
2015
Connective tissue diseases, like systemic lupus erythematosus (SLE), are associated with early and accelerated atherosclerosis. Recently, the concept of “early vascular aging” (EVA) has been more widely accepted. Aortic stiffness is one of the important markers of EVA. We evaluated EVA and subclinical atherosclerosis, by measuring aortic pulse wave velocity (aPWV) and carotid intima–media thickness (cIMT), in 50 normotensive patients with SLE (mean age: 39 ± 12 years). We compared these participants with 50 age- and sex-matched patients with essential hypertension (EH) and 20 healthy controls. Each participant underwent 24-hour ambulatory blood pressure monitoring (ABPM), aPWV, and cIMT me…
Endothelial dysfunction and carotid lesions are strong predictors of clinical events in patients with early stages of atherosclerosis: a 24-month fol…
2008
Background The purpose of this study was to investigate whether the vasodilator response to brachial artery and the presence of carotid lesions may have a prognostic significance in patients with early stages of atherosclerosis. Methods and results Vascular echography was performed to analyze flow-mediated vasodilatation (FMD) at the brachial artery and intima–media thickness (IMT) of carotid arteries in 84 asymptomatic patients. At baseline, we evaluated all the established traditional cardiovascular risk factors. Transient ischemic attack, stroke, effort or unstable angina, acute myocardial infarction, peripheral arterial disease and cerebrovascular and cardiovascular death served as outc…
Prediction of cardio- and cerebro-vascular events in patients with subclinical carotid atherosclerosis and low HDL-cholesterol.
2007
Low HDL-cholesterol concentrations are associated with increased cardiovascular risk and recent evidences suggest that HDL may aggravate the atherosclerotic process promoting inflammation: HDL are anti-inflammatory in the absence of inflammation but can become proinflammatory in the presence of atherosclerosis. Yet, no data is available on the cardiovascular outcome in subjects with low HDL-cholesterol and early stages of atherosclerosis. Therefore, we included in a prospective 5-year follow-up study 150 subjects with low HDL-cholesterol concentrations and subclinical carotid atherosclerosis, as assessed by carotid colour doppler, evaluating at baseline all the established traditional cardi…
Characterization of the cortical laser-doppler flow and hippocampal degenerative patterns after global cerebral ischaemia in the goat.
1998
Large-animal models offer several advantages in the study of cerebral ischaemia: easier control of physiological variables, easier neuropathological evaluation, etc. In the present study we have taken advantage of the unique cerebrovascular anatomy of the goat to reproduce a model of reversible, incomplete, global cerebral ischaemia in a large-sized animal species, in which the effects of successive manoeuvres to stop and re-start cerebral blood flow can be recorded continuously. Early cortical laser-Doppler flow response (up to 2 h) and delayed neuronal degeneration (7 days) in the hippocampal CA1 subfield have been analysed in goats undergoing 5, 10 or 20 min of transient, global cerebral…
Relationship of a Body Shape Index and Body Roundness Index with carotid atherosclerosis in arterial hypertension.
2018
Background and aims: A Body Shape Index (ABSI) and Body Roundness Index (BRI) are two new anthropometric adiposity indices that have shown to be associated better than BMI with adipose abdominal tissue, with the onset of diabetes and the risk of premature death. Little is known about the influence of ABSI and BRI on subclinical vascular damage. The study was aimed to assess the relationship between ABSI and BRI with carotid atherosclerosis damage in subjects with arterial hypertension. Methods and results: A total of 468 patients with arterial hypertension (30–80 years old) were enrolled; adiposity indices were calculated (BMI, WC, ABSI, BRI) and carotid ultrasonographic examination was per…