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Iwata Shinichi S Cardiology Division, Department of Medicine, Columbia University, New York, NY, - - 2013
Aortic valve calcification (AVC) without outflow obstruction (stenosis) is common in the elderly and increases the risk of cardiovascular morbidity and mortality. Although high blood pressure (BP) measured at the doctor's office is known to be associated with AVC, little is known about the association between 24-hour ambulatory BP (ABP) ...
Heim Abigael - - 2012
BACKGROUND:: The systolic augmentation index (sAix), calculated from the central aortic pulse wave (reconstructed from the noninvasive recording of the radial pulse with applanation tonometry), is widely used as a simple index of central arterial stiffness, but has the disadvantage of also being influenced by the timing of the reflected ...
Rudenick Paula A - - 2012
OBJECTIVE: Management and follow-up of chronic aortic dissections continue to be a clinical challenge due to progressive dilatation and subsequent rupture. To predict complications, guidelines suggest follow-up of aortic diameter. However, dilatation is triggered by hemodynamic parameters (pressures/wall shear stresses) and geometry of false (FL) and true lumen (TL), information ...
Zapolski Tomasz - - 2012
ABSTRACT: BACKGROUND: This study was performed to investigate the relationship between elastic properties of aorta and left atrium volume index (LAVI) in hemodialyzed (HD) patients. METHODS: Study group was consisted of 73 patients (age 51,6 +/- 7,6 years) treated by hemodialysis. In all patients standard echocardiography was performed. Aortic stiffness ...
Kim Jungsil J Department of Mechanical Engineering, Michigan State University, East Lansing, Michigan 48824, - - 2013
Understanding the mechanical behavior of the arterial wall and its spatial variations is essential for the study of vascular physiopathology and the design of biomedical devices that interact with the arterial wall. Although it is generally accepted that the aortic wall gets stiffer along its length, the spatial variations in ...
Kırış Abdulkadir - - 2012
Objectives: Left ventricular (LV) dyssynchrony is a common finding in patients with hypertension and is associated with LV hypertrophy. Arterial stiffness (AS) and central (aortic) blood pressures play a significant role in end-organ damage such as LV hypertrophy caused by hypertension. The objective of this study was to investigate the ...
Sádaba Justo Rafael - - 2012
The question of whether left ventricular mass (LVM) regression following aortic valve replacement (AVR) is affected by the prosthesis indexed effective orifice area (IEOA) and transprosthetic gradient has not been fully elucidated. Data from a prospective, core-laboratory-reviewed echocardiography and magnetic resonance imaging (MRI) study was used to determine if the ...
Davis Jason T JT Department of Medicine, VA San Diego Healthcare System and the University of California, San Diego, CA 92093, USA. - - 2013
The aim of the current study was to characterize the effects of the novel β-adrenergic antagonist nebivolol on central aortic blood pressures, arterial properties, and nitroxidergic activity in individuals with prehypertension. Prehypertension is emerging as a major risk factor for several adverse cardiovascular consequences. Increased pulse wave velocity, aortic augmentation ...
Friedman Kevin G KG Department of Cardiology, Children's Hospital Boston and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA. - - 2013
Young patients with congenital aortic valve disease are at risk of left ventricular (LV) diastolic dysfunction (DD). We evaluated LV remodeling and the prevalence of, and risk factors for, DD in patients with aortic stenosis (AS), pure aortic regurgitation (AR), and AS+AR. Patients aged 8 to 39 years with congenital ...
Canpolat Nur - - 2012
BACKGROUND: The aim of this study was to evaluate the presence of subclinical cardiovascular disease (CVD) and its relation to risk factors, particularly hypertension in juvenile-onset systemic lupus erythematosus (SLE). METHODS: A total of 24 patients with normal renal function were examined for subclinical CVD by using non-invasive methods, including ...
Shahin Yousef - - 2012
Objectives: To investigate the relationship of aortic augmentation index (AIx) with N-terminal pro B-type natriuretic peptide (NTproBNP) plasma levels in patients with peripheral arterial disease (PAD) with normal left ventricular (LV) function. Methods: Totally, 31 patients (23 males, mean age 65 ± 7.4) with a confirmed diagnosis of PAD of ...
Scallan Joshua P JP Department of Medical Pharmacology & Physiology, University of Missouri School of Medicine, Columbia, MO 65212, - - 2013
Collecting lymphatic vessels generate pressure to transport lymph downstream to the subclavian vein against a significant pressure head. To investigate their response to elevated downstream pressure, collecting lymphatic vessels containing one valve (incomplete lymphangion) or two valves (complete lymphangion) were isolated from the rat mesentery and tied to glass cannulae ...
Canniffe Carla - - 2012
Hypertension continues to be a common and potentially serious problem in patients who have undergone anatomically successful repair of aortic coarctation. OBJECTIVE: To assess the prevalence of hypertension after aortic coarctation repair, the factors that affect the prevalence and the hypotheses behind hypertension in this cohort of patients. DESIGN: A ...
Kwon Beom-June - - 2012
Thiazide-type diuretics are the most commonly used blood pressure (BP)-lowering drug for patients with uncomplicated hypertension. However, it has remained unclear whether hydrochlorothiazide (HCTZ) or chlorthalidone (CTD) shows better improvement in central aortic pressure. We conducted an open-label, randomized, prospective cross-over study with an 8-week active treatment (HCTZ of 25 mg ...
Rider Oliver J OJ Department of Cardiovascular Medicine, University of Oxford, UK. - - 2013
Increased thoracic ascending aortic stiffness is thought to contribute to concentric left ventricular hypertrophy and increased mortality, a pattern seen in hypertension. As such, aortic stiffness and increased left ventricular mass are candidates by which obesity increases cardiovascular risk. However, obesity is characterized predominantly by increased abdominal aortic stiffness and ...
Chaturvedi Nish - - 2012
Stroke mortality rate is higher in South Asians than in Europeans, despite equivalent or lower resting blood pressure (BP). Elevated recovery BP after exercise predicts stroke, independently of resting values. We hypothesized that South Asians would have adverse postexercise hemodynamics and sought explanations for this. A population-based sample of 147 ...
Bjarnegård Niclas - - 2012
Objectives Intrauterine growth restriction (IUGR) is associated with increased cardiovascular risk later in life. Methods We examined 19 young adults (22-25 years) who were born at term after IUGR and 18 controls, all previously examined with fetal Doppler, and in the present follow-up with echocardiography, carotid echo-tracking ultrasound, applanation tonometry, ...
Wipper Sabine - - 2012
Purpose : To evaluate the hemodynamic impact of transseptal sheath access to the ascending aorta using increasing sheath diameters. Methods : Transseptal puncture was performed in 6 pigs (62±9 kg) facilitating guidewire passage across the left heart to the descending aorta to establish transseptal through-and-through access into the ascending aorta. ...
Ng Chun-Yi - - 2012
Thermally oxidized oil generates reactive oxygen species that have been implicated in several pathological processes including hypertension. This study was to ascertain the role of inflammation in the blood pressure raising effect of heated soybean oil in rats. Male Sprague-Dawley rats were divided into four groups and were fed with ...
Yang Yanmin - - 2012
OBJECTIVES: Retrograde cerebral perfusion (RCP) has been employed to protect the brain during cardiovascular surgery, requiring temporary hypothermic circulatory arrest (HCA). However, the protocol used for RCP remains to be modified if prolonged HCA is expected. The aim of this study was to determine the efficacy of a modified protocol ...
Brandt Mathias C - - 2012
OBJECTIVES: This study investigated the effect of catheter-based renal sympathetic denervation (RD) on central hemodynamics in patients with resistant hypertension. BACKGROUND: High central blood pressure (BP) increases cardiovascular events and mortality independently of peripheral BP. The effect of RD on central BP is unclear. METHODS: A total of 110 patients ...
Karmonik Christof - - 2012
To develop a better understanding of the hemodynamic alterations in the ascending aorta, induced by variation of the cannula outflow position of the left ventricular assist device (LVAD) device based on patient-specific geometries, transient computational fluid dynamics (CFD) simulations using the realizable k-ε turbulent model were conducted for two of ...
Devaraju Naga Sai Gopi K - - 2012
Advances in microfluidics now allow an unprecedented level of parallelization and integration of biochemical reactions. However, one challenge still faced by the field has been the complexity and cost of the control hardware: one external pressure signal has been required for each independently actuated set of valves on chip. Using ...
El Khoudary Samar R SR University of Pittsburgh, Pittsburgh, PA 15261, USA. - - 2012
Limited data are available about risk factors for the progression of aortic stiffness in healthy population. We examined several risk factors as possible independent predictors of aortic stiffness progression among a population-based sample of US men. A total of 240 men (40-49 years) free of CVD at baseline from the ...
Davis Robert Patrick RP Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, United - - 2013
A 7-day infusion of serotonin (5-hydroxytryptamine, 5-HT) causes a sustained fall in elevated blood pressure in the male deoxycorticosterone acetate (DOCA)-salt rat. As hypertension is a long-term disease, we presently test the hypothesis that a longer (30 day) 5-HT infusion could cause a sustained fall in blood pressure in the ...
Cui Xiaopei - - 2012
Grape seed proanthocyanidin extracts (GSPE) belonging to polyphenols, possess various biological effects including anti-inflammation, anti-oxidant, anti-aging, anti-atherosclerosis and et al. GSPE is potential in regulating endothelial function. However, the underlying mechanism is not clear yet. In this study, by siRNA knocking down, we proved that GSPE increase endothelial nitric oxide ...
Phillips Aaron A - - 2012
As sympathetic activity approximately doubles during intense lower body negative pressure (LBNP) of -60 mmHg or greater, we examined the relationship between surrogate markers of sympathetic activation and central arterial distensibility during severe LBNP. Eight participants were exposed to progressive 8-min stages of LBNP of increasing intensity (-20, -40, -60, and ...
Madueme Peace C - - 2012
BACKGROUND: In normotensive subjects, an exaggerated blood pressure response to exercise is associated with the development of resting hypertension. We sought to determine the prevalence of elevated blood pressures during exercise in post-operative coarctation patients with normal resting blood pressure, and investigate associations with exercise-induced hypertension in this population. METHODS: ...
Hayashi Taro - - 2012
Cardiac tamponade is associated with fatal outcomes for patients with acute type A aortic dissection, and the presence of cardiac tamponade should prompt urgent aortic repair. However, treatment of the patient with critical cardiac tamponade who cannot survive until surgery remains unclear. We analyzed our experience of controlled pericardial drainage ...
Lee Melissa G Y - - 2012
OBJECTIVES: To determine by 24-hour blood pressure monitoring the risk of hypertension late after coarctation repair in patients with arch hypoplasia. METHODS: Sixty-two of 116 consecutive patients (age, ≥10 years) who had coarctation repair and were quoted subjectively by the surgeon or the cardiologist to have arch hypoplasia at the ...
Mortensen Kai - - 2012
J Clin Hypertens (Greenwich). 2012;14:861-870. ©2012 Wiley Periodicals, Inc. Renal sympathetic denervation (RDN) is a novel treatment strategy for patients with resistant arterial hypertension. Recently, the Symplicity trials demonstrated significant peripheral blood pressure (BP) reduction. The present study aimed at measuring central aortic pressures and arterial stiffness as better predictors ...
Curran Sarah A - - 2012
Pressure distribution measurement offers an objective and quantifiable method of determining the loads applied to the human body during static and dynamic situations such as walking and the more demanding tasks associated with sporting activities. While there are various systems available on the market, the technology and developments offered by ...
Annavarajula S K - - 2012
Chronic kidney disease (CKD) is a growing problem worldwide. The disproportionate increase in the burden of cardiovascular disease in patients with CKD may be significantly contributed by nontraditional risk factors. Increased arterial stiffness has been recognized as an important player in contributing to this morbidity and mortality. The aim of ...
Mason R Preston - - 2012
ABSTRACT:: Most patients with diabetes also have hypertension, a risk factor associated with atherothrombotic disease and characterized by endothelial cell (EC) dysfunction and loss of nitric oxide (NO) bioavailability. Recent studies suggest a possible antihypertensive effect with dipeptidyl peptidase-4 (DPP4) inhibition; however, the underlying mechanism is not understood. In this ...
Okamura Homare - - 2012
PURPOSE: The effective orifice area index (EOAI) is used to define the prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR). However, few studies have so far evaluated whether the cutoff value for PPM varies across prostheses. This study assessed the hemodynamics in patients given a mechanical valve and then re-evaluated ...
Fordyce P M - - 2012
Multilayer soft lithography (MSL) provides a convenient and low-cost method for fabricating poly(dimethyl siloxane) (PDMS) microfluidic devices with on-chip valves for automated and precise control of fluid flow. MSL casting molds for flow channels typically incorporate small patches of rounded positive photoresist at valve locations to achieve the rounded cross-sectional ...
Reisman William M - - 2012
BACKGROUND: Near infrared spectroscopy (NIRS) has been suggested as a possible means for detecting perfusion deficits in patients with acute compartment syndrome (ACS). STUDY OBJECTIVES: To longitudinally examine NIRS in an ACS model to determine its responsiveness to decreasing perfusion pressure. METHODS: A NIRS sensor pad was placed under a ...
Dang Yong-Qiang - - 2012
FRET has been used as a powerful tool in biological fields as biosensors, bioimaging, protein folding/unfolding monitoring, biomolecular interactions and so on. It is also important to applying FRET to high hydrostatic pressure studies on bio- or bio-related systems. Herein, we construct a FRET system by labeling Cy3 on C-phycocyanin ...
Webb Alastair J S AJ Stroke Prevention Research Unit, University of Oxford, Oxford, - - 2012
Arterial stiffening reduces damping of the arterial waveform and hence increases pulsatility of cerebral blood flow, potentially damaging small vessels. In the absence of previous studies in patients with recent transient ischemic attack or stroke, we determined the associations between leukoaraiosis and aortic and middle cerebral artery stiffness and pulsatility. ...
Gu Kaiyun - - 2012
The intraaorta pump is a novel left ventricular assist device (LVAD) whose hemodynamic effects on the circulatory system is unknown. This article aims to evaluate the different effects on the circulatory system supported by the intraaorta pump. In this article, the pump is controlled by three control strategies, including the ...
Reymond Philippe - - 2012
One-dimensional models of the systemic arterial tree are useful tools for studying wave propagation phenomena, however, their formulation for frictional losses is approximate and often based on solutions for developed flow in straight non-tapered arterial segments. Thus, losses due to bifurcations, tortuosity, non-planarity and complex geometry effects cannot be accounted ...
Cihan Abdullah - - 2012
Carbon dioxide injection into deep saline formations may induce large-scale pressure increases and migration of native fluid. Local high-conductivity features, such as improperly abandoned wells or conductive faults, could act as conduits for focused leakage of brine into shallow groundwater resources. Pressurized brine can also be pushed into overlying/underlying formations ...
Tamegai Hideyuki - - 2012
It is known that the facultative piezophile Shewanella violacea DSS12 alters its respiratory components under the influence of hydrostatic pressure during growth. This can be considered one of the mechanisms of bacterial adaptation to high pressure. In this study, we investigated the respiratory system of another well-studied piezophile, Photobacterium profundum ...
Parichatikanond Warisara - - 2012
Overactivation of the renin-angiotensin system is one of the most important risk factors for the development of hypertension. The use of the crude extracts and/or active compounds, such as anthocyanins and quercetin, of herbal plants that have antihypertensive effects is beneficial for decreasing of blood pressure level. However, the molecular ...
Nepple Kenneth G KG Division of Urology, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA. - - 2013
Previous experimental research has reported minimal differences in pressure maintenance between different versions of standard insufflators (SI). However, a recent report identified potential clinical benefits with a valveless pressure barrier insufflator (PBI). We sought to perform a benchtop objective evaluation of SI and PBI systems. A rigid box system with ...
de Oliveira Fabricio Ferreira - - 2012
Normal pressure hydrocephalus is an unusual manifestation of systemic lupus erythematosus and its pathogenesis is still unclear. We report the case of a 39-year-old white woman with systemic lupus erythematosus who developed magnetic gait, speech difficulties, progressive memory impairment, urinary incontinence and episodes of involuntary closure of the eyelids. Signs ...
Ji Xiaoyan - - 2012
For CO2 geological storage, permitting impurities, such as H2S, in CO2 streams can lead to a great potential for capital and energy savings for CO2 capture and separation, but it also increases costs and risk management for transportation and storage. To evaluate the cost - benefits, using a recently developed ...
Melamed Roman - - 2012
OBJECTIVES: Invasive blood pressure monitoring is the most reliable method in critically ill patients. Noninvasive oscillometric pressure monitoring is also widely used in the ICU, and discrepancies between the methods are common. Inclusion of a blood-conserving device may influence the fidelity of the system and reliability of the invasive pressure ...
Etemadi M - - 2012
Congenital pulmonary hypoplasia is a devastating condition affecting fetal and newborn pulmonary physiology, resulting in great morbidity and mortality. The fetal lung develops in a fluid-filled environment. In this work, we describe a novel, implantable pressure sensing and recording device which we use to study the pressures present in the ...
Toal Corey B - - 2012
Calcium-channel blockers (CCBs) constitute a diverse group of compounds but are often referred to as a single homogeneous class of drug and the clinical responses indiscriminately summarized. Even within the dihydropyridine subgroup, there are significant differences in formulations, pharmacokinetics, durations of action and their effects on blood pressure, heart rate, ...
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