Search results for "Wave velocity"

Assessment of conduit artery vasomotion using photoplethysmography

2013

Vasomotion is a spontaneous oscillation of vascular tone. The phenomenon has been observed in small arterioles and capillaries as well as in the large conduit arteries. The layer of smooth muscle cells that surrounds a blood vessel can spontaneously and periodically change its tension and thereby the arterial wall stiffness also changes. As the understanding of the phenomenon is still rather obscure, researchers would benefit from a low-cost and reliable investigation technique such as photoplethysmography (PPG). PPG is an optical blood pulsation measurement technique that can offer substantial information about the arterial stiffness. The aims of this pilot study were to evaluate the usefu…

2021

ObjectiveLoss of sex hormones has been suggested to underlie menopause-associated increment in cardiovascular risk. We investigated associations of sex hormones with arterial stiffness in 19–58-years-old women. We also studied associations of specific hormonal stages, including natural menstrual cycle, cycle with combined oral contraceptives (COC) and menopausal status with or without hormone therapy (HT), with arterial stiffness.MethodsThis study includes repeated measurements of 65 healthy women representing reproductive (n=16 natural, n=10 COC-users) and menopause (n=5 perimenopausal, n=26 postmenopausal, n=8 HT-users) stages. Arterial stiffness outcomes were aortic pulse wave velocity (…

Unfavourable interaction of microalbuminuria and mildly reduced creatinine clearance on aortic stiffness in essential hypertension

2010

The aim of our study was to assess the independent relationships of urinary albumin excretion rate (AER), of creatinine clearance (CrCl) and of their interaction with aortic stiffness in hypertensive patients without overt renal insufficiency. We studied 222 untreated nondiabetic essential hypertensives. In patients with reliable 24-h urine collections, AER and CrCl were determined. Microalbuminuria (MAU) was defined as an AER of 20 to 200microg/min. Aortic stiffness was assessed by measurement of carotid-femoral pulse wave velocity (c-f PWV). C-f PWV was higher in subjects with MAU than in those without it (p<0.001, even after adjustment for age, sex and mean arterial pressure) and in subj…

X-ray diffraction measurements of Mo melting to 119 GPa and the high pressure phase diagram

2009

In this paper, we report angle-dispersive X-ray diffraction data of molybdenum melting, measured in a double-sided laser-heated diamond-anvil cell up to a pressure of 119 GPa and temperatures up to 3400 K. The new melting temperatures are in excellent agreement with earlier measurements up to 90 GPa that relied on optical observations of melting and in strong contrast to most theoretical estimates. The X-ray measurements show that the solid melts from the bcc structure throughout the reported pressure range and provide no evidence for a high temperature transition from bcc to a close-packed structure, or to any other crystalline structure. This observation contradicts earlier interpretation…

Immune-inflammatory markers and arterial stiffness indexes in subjects with acute ischemic stroke with and without metabolic syndrome.

2014

Objective: The aim of our study was to evaluate the associations between arterial stiffness indexes and immune-inflammatory markers in subjects with acute ischemic stroke with and without metabolic syndrome. Materials/Methods: We enrolled 130 patients with acute ischemic stroke and metabolic syndrome, 127 patients with acute ischemic stroke without metabolic syndrome and 120 control subjects without acute stroke. Applanation tonometry was used to record the augmentation index (Aix) and pulse wave velocity (PWV). We also evaluated plasma levels of C-reactive protein (CRP), Interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6) and Interleukin-10 (IL-10), E-selec…

Arterial stiffness in symptomatic smokers with normal lung function

2017

Chronic obstructive pulmonary disease (COPD) is associated with cardiovascular morbidity and mortality. Arterial stiffness and endothelial dysfunction index are validated surrogate cardiovascular markers and are increased in subjects with COPD. We tested whether increased arterial stiffness and endothelial dysfunction occur in symptomatic smokers with no evidence of bronchial obstruction. Clinical and lung functional assessments were conducted in smoker subjects with chronic respiratory symptoms and in COPD patients. Pulse wave velocity (PWV), aortic augmentation index (AIx) and reactive hyperaemia index (RHI) were measured to estimate the cardiovascular risk. 48 smokers (male n=37, female …

RELATIONSHIP BETWEEN SERUM URIC ACID AND AORTIC STIFFNESS IN UNTREATED HYPERTENSIVE SUBJECTS

2013

Recent studies have reported an association between serum uric acid (SUA) and reduced arterial elasticity. However, in these studies arterial elastic properties have been assessed chiefly by measuring brachial-ankle pulse wave velocity (PWV) or peripheral PWV and only sometimes by using aortic PWV. Moreover, the relationships between SUA and arterial stiffness have never been statistically adjusted for albuminuria. Furthermore, the studies exploring the influence of uric acid on aortic distensibility in subjects with arterial hypertension yielded conflicting results. The aim of our study was to evaluate the relationships between SUA and aortic stiffness in a group of essential hypertensive …

ASSOCIATION OF RENAL RESISTIVE INDEX WITH AORTIC PULSE WAVE VELOCITY IN HYPERTENSIVE PATIENTS.

2013

The assessment of renal hemodynamic parameters by duplex Doppler sonography has been used for many years as a diagnostic tool in the daily work-up of kidney diseases. Recent data suggest that these parameters, especially the intrarenal resistive index (RI) may be also associated with systemic vascular changes and with an enhanced cardiovascular risk. However, conflicting data exist in literature about the independent association of aortic stiffness with RI. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (PWV), in the hypertensive subjects consecutively attending our hypertension centre. We enrolled 264 subject…

Correlations between non ivasive renal index and markers of atherosclerosis in lupus patients

2014

Recent data suggest that renal hemodynamic parameters obtained by duplex Doppler sonography, especially the intrarenal resistive index (RI), may be associated with systemic vascular changes in some groups of patients. However, conflicting data exist about the relationship between aortic stiffness and RI in autoimmune disease, like systemic lupus erythematosus, characterized by high and early incidence of atherosclerotic disease. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (aPWV), and carotid atherosclerosis, evaluated by intimal medial thickness measurement (IMT) in patients with SLE. DESIGN: Cross-sectiona…

Early vascular aging in normotensive subjects with systemic lupus erythematous. Comparison with young hypertensive patients

2014

early vascular aging