Search Results
Results 201 - 250 of 1760
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Lieb Wolfgang - - 2009
Arterial stiffness increases with age and contributes to the pathogenesis of systolic hypertension and cardiovascular disease in the elderly. Knowledge about the pathophysiological processes that determine arterial stiffness may help guide therapeutic approaches. We related 7 circulating biomarkers representing distinct biological pathways (C-reactive protein, aldosterone-to-renin ratio, N-terminal proatrial natriuretic peptide ...
Khandanpour Nader - - 2010
OBJECTIVE: The aim of this study was to assess the relationship between ankle brachial pressure index and pulse wave velocity in patients with peripheral arterial disease. METHODS: Brachial-knee and brachial-ankle pulse wave velocity were measured by pneumoplethysmography using cuffs in a standard technique. Correlation between pulse wave velocity and Doppler-ankle ...
Westhoff T H - - 2009
There is an increasing number of wrist blood pressure measurement devices that successfully passed the validation procedures of the British Hypertension Society (BHS) and the European Society of Hypertension (ESH). It remains unknown, however, whether pulse pressure as a marker of arterial stiffness and vascular ageing affects the accuracy of ...
Kips Jan G - - 2009
Accurate quantification of pressure wave reflection requires separation of pressure in forward and backward components to calculate the reflection magnitude as the ratio of the amplitudes backward and forward pressure. To do so, measurement of aortic flow in addition to the pressure wave is mandatory, a limitation that can be ...
Rajani Ronak - - 2008
OBJECTIVES: To determine the relationship between brachial blood pressure, and transfer function-estimated and invasively measured central aortic pressure in patients with at least moderate symptomatic aortic stenosis. METHODS: Fourteen patients aged 54-81 years with mean (SD) effective valve area of 0.69 (0.20) cm2, undergoing coronary angiography, had simultaneous peripheral and ...
Scurrah Katrina J - - 2008
We have demonstrated that familial genetic and shared environmental factors influence postural responses of blood pressure, such that some families show a fall and others show a rise in systolic pressure on standing. These differences might reflect programmed differences in the underlying responses in mean arterial pressure and pulse pressure ...
Hermeling Evelien - - 2008
OBJECTIVES: Local pulse wave velocity, a direct measure of arterial stiffness, can be measured using the systolic foot of the pressure waveform as the time reference point. The accuracy and precision of systolic foot identification, which may be disturbed by early wave reflections, heavily affects pulse wave transit time measurements. ...
Norton Gavin R - - 2008
AIM: We sought to determine whether prehypertension (BP = 120-139/80-89 mmHg) is associated with target organ changes independent of confounders. METHODS: In 771 participants from a population sample of African ancestry, approximately 46% of whom had hypertension, and approximately 30% prehypertension, organ damage was assessed from echocardiography (left ventricular mass ...
Wang J-M - - 2009
Vascular dysfunction in hypertensive condition is characterized by impaired endothelial function and reduced artery elasticity. Circulating endothelial microparticles (EMPs) and brachial-ankle pulse wave velocity (baPWV) are novel evaluation parameters for vascular function. However, their changes in patients with well-controlled blood pressure (BP) have not been fully acquired. To address this ...
Franek Edward - - 2009
The aim of the study was to answer the question whether chronic periodontitis (CP) in patients with essential hypertension is associated with increased aortic stiffness and increased central blood pressure (CBP), which may in turn increase left ventricular mass (LVM) in those patients. CP influences LVM in hypertensive and renal ...
Rakebrandt F - - 2009
Wave intensity (WI) in the circulation is estimated noninvasively as the product of instantaneous changes in pressure and velocity. We recorded diameter as a surrogate for pressure, and velocity in the right common carotid artery using an Aloka SSD-5500 ultrasound scanner. We developed automated software, applying the water hammer equation ...
Michel Anna P M - - 2008
Laser-induced breakdown spectroscopy (LIBS) has been identified as an analytical chemistry technique suitable for field use. We use double pulse LIBS to detect five analytes (sodium, manganese, calcium, magnesium, and potassium) that are of key importance in understanding the chemistry of deep ocean hydrothermal vent fluids as well as mixtures ...
Michel Anna P M - - 2008
The ability of oceanographers to make sustained measurements of ocean processes is limited by the number of available sensors for long-term in situ analysis. In recent years, laser-induced breakdown spectroscopy (LIBS) has been identified as a viable technique to develop into an oceanic chemical sensor. We performed single pulse laser-induced ...
Hsu Tse Lin - - 2008
AIMS: Previously, we found that qi-stimulating events exerted similar frequency-specific effects on the blood pressure pulse spectrum. Because coffee and qi induce similar stimulatory psychological responses, we aimed to determine whether they would induce similar pulse effects. Such a relationship would suggest a close linkage between the physiologic mechanisms underlying ...
Protogerou Athanassios D - - 2008
INTRODUCTION: Acute and chronic inflammation has a deleterious effect on arterial structure and function. Increased arterial stiffness and pressure wave reflections may provide a pathophysiological link between inflammation and increased cardiovascular risk. Adamantiades-Behcet disease (ABD), a relapsing inflammatory vasculitis, is associated with impaired arterial properties modulated by corticosteroids. The effect ...
Cay Serkan - - 2008
BACKGROUND: Coronary artery bypass grafting has a mortality benefit compared to medical therapy in some patient groups, such as those with left main or left anterior descending coronary artery disease, and those with left ventricular dysfunction. Therefore, patency of grafts, especially sapheneous grafts, is an important issue. Aortic pulse and ...
Hong Chinsuk - - 2008
This paper reports the characteristics of wall pressure fluctuations in the transition region of the flow over axisymmetric bodies. Measurements are conducted in a low noise wind tunnel to obtain the boundary-layer flow field, the local static pressures, and the wall pressure fluctuations using hot wires, micromanometers and flush-mounted microphones. ...
Yildiz Mustafa - - 2008
BACKGROUND AND AIM: Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease affecting young women and is associated with increased frequency of atherosclerotic vascular diseases. Pulse wave velocity (PWV) is an index of arterial stiffness and a marker of cardiovascular events. This study aimed to investigate arterial distensibility using ...
Landsverk Svein Aslak - - 2008
BACKGROUND: To identify fluid responsiveness, a correlation between respiratory variations in pulse pressure (DeltaPP) and respiratory variations in pulse oximetry photoplethysmographic waveform amplitude (DeltaPOP) in mechanically ventilated patients has been demonstrated. To evaluate the agreement between the two methods, knowledge about the repeatability of the methods is imperative. However, no ...
Henskens Léon H G - - 2008
Aortic stiffness predicts an excess risk of stroke, supposedly via cerebral small-vessel disease. White matter hyperintensities, silent lacunar infarcts, and brain microbleeds, manifestations of cerebral small-vessel disease on neuroimaging, may precede overt cerebrovascular disease. Therefore, we assessed whether aortic stiffness is also related to such lesions. In 167 hypertensive patients ...
Westerhof Berend E - - 2008
Central aortic pressure gives better insight into ventriculo-arterial coupling and better prognosis of cardiovascular complications than peripheral pressures. Therefore transfer functions (TF), reconstructing aortic pressure from peripheral pressures, are of great interest. Generalized TFs (GTF) give useful results, especially in larger study populations, but detailed information on aortic pressure might ...
Haiden Mio - - 2008
BACKGROUND: Although brachial-ankle pulse wave velocity is a widely used index of arterial stiffness, there are several limitations of this method. The actual length of an artery used for measuring pulse wave velocity is estimated based on an anatomical correction value, and brachial-ankle pulse wave velocity is directly affected by ...
Matsui Yoshio - - 2008
OBJECTIVE: Lowering of the central pulse pressure (PP) has been shown to contribute to an improvement of the cardiac damage beyond that of lowering the brachial PP. We assessed the hypothesis that the change in the central PP is more useful than that in the brachial PP in the assessment ...
Auler Jose Otavio C JO - - 2008
In critically ill patients, it is important to predict which patients will have their systemic blood flow increased in response to volume expansion to avoid undesired hypovolemia and fluid overloading. Static parameters such as the central venous pressure, the pulmonary arterial occlusion pressure, and the left ventricular end-diastolic dimension cannot ...
Dias A R AR - - 2008
METHODS: We analyzed the influence of conjugated equine estrogen (CEE) and raloxifene on arterial stiffness. Sixty-seven healthy, normotensive women 1-10 years into menopause were assigned to receive oral placebo, conjugated equine estrogen 0.625 mg, or raloxifene 60 mg. Arterial stiffness was evaluated by measuring the carotid-femoral and femoral-dorsalis pedis pulse ...
Courtney A C - - 2009
The mechanisms by which blast pressure waves cause mild-to-moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast wave via the cranium, and propagation of the blast wave to the brain via a thoracic mechanism. The hypothesis that the blast ...
Madias John E - - 2008
Electrocardiographic low QRS voltage (LQRSV) has many causes, which can be differentiated into those due to the heart's generated potentials (cardiac) and those due to influences of the passive body volume conductor (extracardiac). Peripheral edema of any conceivable etiology induces reversible LQRSV, reduces the amplitude of the P waves and ...
van der Wegen-Franken Karin - - 2008
Compression therapy with medical elastic compression stockings (MECS) has been used effectively for treating patients with chronic venous insufficiency for many years. To study the correlation between static stiffness and the dynamic stiffness index of 18 different brands of MECS. In all, 18 different brands of MECS were divided into ...
Atlas Glen M - - 2008
The esophageal Doppler monitor (EDM) is a clinically useful device for minimally invasive assessment of cardiac output, preload, afterload, and contractility. An empirical model, based upon the logistic function, has been developed. Use of this model illustrates how the EDM could estimate the net effect of aortic and non-aortic contributions ...
Abbatecola Angela M - - 2008
BACKGROUND: Cognitive decline that occurs frequently in impaired glucose tolerance (IGT) may be largely due to endothelial dysfunction. We assessed: (i) the relationships between impact of urinary albumin excretion rate (UAER), as marker of generalized endothelial dysfunction, and cognition; (ii) if cognitive decline could be explained by arterial stiffening using ...
Li Li - - 2008
The velocities of seismic waves in the Earth are governed by the response of the constituent mineral assemblage to perturbations in pressure and stress. The effective bulk modulus is significantly lowered if the pressure of the seismic wave drives a volume-reducing phase transformation. A comparison between the amount of time ...
Tada Tomohiro - - 2008
AIMS: Clinical studies have suggested that pulsatile pressure is an independent risk factor for atherosclerosis. However, it is unknown whether enhanced pulsatile pressure per se directly accelerates vascular smooth muscle cell (VSMC) migration, an important process of atherosclerosis. METHODS AND RESULTS: Using our original Pressure-loading system with a Boyden chamber, ...
Venugopal Deviprasad - - 2009
BACKGROUND: Diagnostic evaluation of patients with suspected symptomatic arrhythmias is limited by inability to assess the hemodynamic impact of a detected rhythm. OBJECTIVE: To address this limitation, we utilized closely spaced subcutaneous electrodes, small enough to incorporate within an implantable monitor, to detect blood flow-induced pectoral muscle bioimpedance (Z) changes ...
Libhaber Elena - - 2008
AIM: As it is uncertain whether arterial stiffness is related to left ventricular mass and left ventricle mean wall thickness independent of blood pressure measured at the brachial artery, we aimed to ascertain this effect in never-treated participants with a high prevalence of risk factors for large artery dysfunction. METHODS: ...
Amoozgar Hamid - - 2009
The presence or absence of pulsus paradoxus (PP), defined as an inspiratory decrease greater than 10 mmHg in systolic blood pressure, can have significant diagnostic and therapeutic implications for many clinical conditions including acute asthma, pericardial tamponade, heart failure, hypovolemia, shock states, and the like. However, PP may be difficult ...
Hadjiloizou Nearchos - - 2008
Despite having almost identical origins and similar perfusion pressures, the flow-velocity waveforms in the left and right coronary arteries are strikingly different. We hypothesized that pressure differences originating from the distal (microcirculatory) bed would account for the differences in the flow-velocity waveform. We used wave intensity analysis to separate and ...
Lazar Jason M - - 2008
Swimming/hydrotherapy produces hemodynamic and physiological changes related to water immersion (WI). To evaluate the effects of head out (HO) WI on central hemodynamics, we prospectively studied 21 healthy subjects (62% male, age 37 +/- 13 years). Central aortic blood pressures (CA-BPs) and reflected wave properties were evaluated using applanation tonometry ...
Gosse Philippe - - 2008
OBJECTIVES: Arterial stiffness increases with age, diabetes and hypertension, and is linked to the occurrence of cardiovascular complications, independently of traditional risk factors. The important influence of age and blood pressure on arterial stiffness and cardiovascular risk complicates analysis of factors involved in increased arterial stiffness. Study of the PROOF ...
Steeghs Neeltje - - 2008
PURPOSE: Hypertension is a commonly reported side effect in antiangiogenic therapy. We investigated the hypothesis that telatinib, a small molecule angiogenesis inhibitor, impairs vascular function, induces rarefaction, and causes hypertension. EXPERIMENTAL DESIGN: A side-study was done in a phase I trial of telatinib, a small molecule tyrosine kinase inhibitor of ...
Guelen Ilja - - 2008
OBJECTIVES: Aortic stiffness is an independent predictor of cardiovascular morbidity and mortality. We investigated whether aortic stiffness, estimated as aortic pulse wave velocity, is associated with decreased perfusion pressure estimated as the cardiac oxygen supply potential. METHODS: Aortic stiffness and aortic pressure waves, reconstructed from finger blood pressure waves, were ...
Lee Ho Won - - 2008
One of three adults and more than 7 of 10 older persons in the United States have hypertension. Of those receiving antihypertensive medication, more than 40% have inadequate blood-pressure control. The predominant subtype of hypertension among older adults is isolated systolic hypertension, which results from stiffening of the wall of ...
Chemla Denis - - 2008
PURPOSE OF REVIEW: To briefly review recent advances in the noninvasive assessment of arterial pressure (indirect methods) in the field of critical care. RECENT FINDINGS: Automated oscillometric measurements underestimate intraarterial systolic blood pressure. Digital photoplethysmography has led to conflicting results, although the obtained respiratory pulse pressure variation correlates with the ...
Zanardo Vincenzo - - 2008
Widened pulse pressure is a classic sign of significant left-to-right shunting patent ductus arteriosus (PDA), but little evidence supports this statement in the early life of premature infants with respiratory distress syndrome (RDS) needing nonsteroidal anti-inflammatory drugs (NSAIDs), the pharmacological treatment for PDA. Pulse pressure and urinary endothelin-1 (ET-1) and ...
Olafiranye Oladipupo - - 2009
BACKGROUND: increased arterial stiffness is a predictor of cardiovascular events. The stroke volume (SV) to pulse pressure (PP) ratio is an estimate of arterial capacitance. Pulse wave velocity (PWV) is a measure of arterial stiffness. This study evaluated the effect of left ventricular (LV) SV on the SV/PP-PWV relationship. METHODS: ...
Ikonomidis Ignatios - - 2008
BACKGROUND: Coronary microcirculation is disturbed in essential hypertension. We investigated whether arterial stiffness determines coronary flow reserve (CFR) in hypertensive patients. METHODS: We examined 100 never-treated hypertensives and 20 healthy controls. We measured (i) carotid-to-femoral pulse wave velocity (PWV); (ii) Systolic (V (s)) and diastolic (V (d)) coronary flow velocity, ...
Foo Jong Yong Abdiel - - 2008
Ankle brachial index is useful in monitoring the pathogenesis of peripheral arterial occlusive diseases. Sphygmomanometer is the standard instrument widely used but frequent prolonged monitoring can be less comfortable for patients. Pulse transit time is known to be inversely correlated with blood pressure and a ratio-based pulse transit time measurement ...
Kim Jung Soo - - 2008
Two confounding factors were selected and analyzed in blood pressure estimation using pulse arrival time (PAT) for each individual. The heart rate was used as the confounding factor for the cardiac cycle, and the duration from the maximum derivative point to the dicrotic peak (TDB) in the photoplethysmogram was used ...
Yildiz Mustafa - - 2008
BACKGROUND: P-wave dispersion, an electrocardiographic marker, is an independent predictor of atrial fibrillation. P-wave dispersion is associated with inhomogeneous and discontinuous propagation of sinus impulses. The aim of this study was to investigate P-wave dispersion in students who apply for registration to School of Physical Education and Sports. METHODS: Totally ...
Delles Christian - - 2008
OBJECTIVES: Oxidative stress causes endothelial dysfunction and plays a major role in the pathogenesis of cardiovascular disease. Increased vascular stiffness is an intermediate phenotype in the development of cardiovascular disease. We hypothesized that vascular stiffness is partially determined by oxidative stress. METHODS: We examined 163 participants out of whom 80 ...
Aguado-Sierra J - - 2008
Previous studies based on measurements made in the ascending aorta have demonstrated that it can be useful to separate the arterial pressure P into a reservoir pressure P* generated by the windkessel effect and a wave pressure p generated by the arterial waves: P = P*+p. The separation in these ...
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