AnatomyOrganismsDiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPhenomena and ProcessesDisciplines and OccupationsTechnology, Industry, AgricultureInformation ScienceHealth Care
Pulsatile FlowBlood Flow VelocityModels, CardiovascularReplica TechniquesRegional Blood FlowRheologyHemorheologyStress, MechanicalModels, AnatomicShear StrengthPericytesEquipment DesignUltrasonography, Doppler, ColorFlow CytometryVeinsPhantoms, ImagingHeart-Assist DevicesPulmonary CirculationEchocardiography, Doppler, ColorCoronary CirculationBlood PressureHemodynamicsPressureBlood Vessel ProsthesisBlood VesselsFemoral ArteryCarotid ArteriesHeart Valve ProsthesisPerfusionIntracranial AneurysmArteriesMaterials TestingEndothelium, VascularComputer SimulationProsthesis DesignNitric Oxide Synthase Type IIITime FactorsCoronary VesselsAortaBiomechanical PhenomenaReproducibility of ResultsSwineDogsGene FlowModels, BiologicalCattleCells, Cultured
Pulsatile Flow
Rhythmic, intermittent propagation of a fluid through a BLOOD VESSEL or piping system, in contrast to constant, smooth propagation, which produces laminar flow.
Blood Flow Velocity
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
Models, Cardiovascular
Theoretical representations that simulate the behavior or activity of the cardiovascular system, processes, or phenomena; includes the use of mathematical equations, computers and other electronic equipment.
Replica Techniques
Methods of preparing tissue specimens for visualization using an electron microscope, usually a scanning electron microscope. The methods involve the creation of exact copies of the specimens by making a mold or cast (i.e., replica) of the specimen.
Regional Blood Flow
The flow of BLOOD through or around an organ or region of the body.
Rheology
The study of the deformation and flow of matter, usually liquids or fluids, and of the plastic flow of solids. The concept covers consistency, dilatancy, liquefaction, resistance to flow, shearing, thixotrophy, and VISCOSITY.
Hemorheology
The deformation and flow behavior of BLOOD and its elements i.e., PLASMA; ERYTHROCYTES; WHITE BLOOD CELLS; and BLOOD PLATELETS.
Stress, Mechanical
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
Models, Anatomic
Three-dimensional representation to show anatomic structures. Models may be used in place of intact animals or organisms for teaching, practice, and study.
Shear Strength
The internal resistance of a material to moving some parts of it parallel to a fixed plane, in contrast to stretching (TENSILE STRENGTH) or compression (COMPRESSIVE STRENGTH). Ionic crystals are brittle because, when subjected to shear, ions of the same charge are brought next to each other, which causes repulsion.
Pericytes
Unique slender cells with multiple processes extending along the capillary vessel axis and encircling the vascular wall, also called mural cells. Pericytes are imbedded in the BASEMENT MEMBRANE shared with the ENDOTHELIAL CELLS of the vessel. Pericytes are important in maintaining vessel integrity, angiogenesis, and vascular remodeling.
Equipment Design
Methods of creating machines and devices.
Ultrasonography, Doppler, Color
Ultrasonography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image. This type of ultrasonography is well-suited to identifying the location of high-velocity flow (such as in a stenosis) or of mapping the extent of flow in a certain region.
Flow Cytometry
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
Veins
The vessels carrying blood away from the capillary beds.
Phantoms, Imaging
Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)
Heart-Assist Devices
Small pumps, often implantable, designed for temporarily assisting the heart, usually the LEFT VENTRICLE, to pump blood. They consist of a pumping chamber and a power source, which may be partially or totally external to the body and activated by electromagnetic motors.
Pulmonary Circulation
The circulation of the BLOOD through the LUNGS.
Echocardiography, Doppler, Color
Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.
Coronary Circulation
The circulation of blood through the CORONARY VESSELS of the HEART.
Blood Pressure
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
Hemodynamics
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
Pressure
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Blood Vessel Prosthesis
Device constructed of either synthetic or biological material that is used for the repair of injured or diseased blood vessels.
Blood Vessels
Any of the tubular vessels conveying the blood (arteries, arterioles, capillaries, venules, and veins).
Femoral Artery
The main artery of the thigh, a continuation of the external iliac artery.
Carotid Arteries
Either of the two principal arteries on both sides of the neck that supply blood to the head and neck; each divides into two branches, the internal carotid artery and the external carotid artery.
Heart Valve Prosthesis
A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.
Perfusion
Treatment process involving the injection of fluid into an organ or tissue.
Intracranial Aneurysm
Abnormal outpouching in the wall of intracranial blood vessels. Most common are the saccular (berry) aneurysms located at branch points in CIRCLE OF WILLIS at the base of the brain. Vessel rupture results in SUBARACHNOID HEMORRHAGE or INTRACRANIAL HEMORRHAGES. Giant aneurysms (>2.5 cm in diameter) may compress adjacent structures, including the OCULOMOTOR NERVE. (From Adams et al., Principles of Neurology, 6th ed, p841)
Arteries
The vessels carrying blood away from the heart.
Materials Testing
The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.
Endothelium, Vascular
Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.
Computer Simulation
Computer-based representation of physical systems and phenomena such as chemical processes.
Prosthesis Design
The plan and delineation of prostheses in general or a specific prosthesis.
Nitric Oxide Synthase Type III
A CALCIUM-dependent, constitutively-expressed form of nitric oxide synthase found primarily in ENDOTHELIAL CELLS.
Time Factors
Elements of limited time intervals, contributing to particular results or situations.
Coronary Vessels
The veins and arteries of the HEART.
Aorta
The main trunk of the systemic arteries.
Biomechanical Phenomena
The properties, processes, and behavior of biological systems under the action of mechanical forces.
Reproducibility of Results
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Swine
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Dogs
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
Gene Flow
The change in gene frequency in a population due to migration of gametes or individuals (ANIMAL MIGRATION) across population barriers. In contrast, in GENETIC DRIFT the cause of gene frequency changes are not a result of population or gamete movement.
Models, Biological
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Cattle
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Cells, Cultured
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.

Pulsatile shear stress leads to DNA fragmentation in human SH-SY5Y neuroblastoma cell line. (1/1458)

1. Using an in vitro model of shear stress-induced cell injury we demonstrate that application of shear to differentiated human SH-SY5Y cells leads to cell death characterized by DNA fragmentation. Controlled shear stress was applied to cells via a modified cone and plate viscometer. 2. We show that pulsatile shear stress leads to DNA fragmentation, as determined via flow cytometry of fluorescein-12-dUTP nick-end labelled cells, in 45 +/- 4 % of cells. No lactate dehydrogenase (LDH) release was observed immediately after injury; however, 24 h after injury significant LDH release was observed. 3. Nitric oxide production by cells subjected to pulsatile shear increased two- to threefold over that in unsheared control cells. 4. Inhibition of protein synthesis, nitric oxide production, Ca2+ entry into cells, and pertussis toxin-sensitive G protein activation attenuated the shear stress-induced cell injury. 5. Our results show for the first time that application of pulsatile shear stress to a neuron-like cell in vitro leads to nitric oxide-dependent cell death.  (+info)

Independent prognostic information provided by sphygmomanometrically determined pulse pressure and mean arterial pressure in patients with left ventricular dysfunction. (2/1458)

OBJECTIVES: The purpose of this study was to evaluate the relationship of baseline pulse pressure and mean arterial pressure to mortality in patients with left ventricular dysfunction. BACKGROUND: Increased conduit vessel stiffness increases pulse pressure and pulsatile load, potentially contributing to adverse outcomes in patients with left ventricular dysfunction. METHODS: Pulse and mean arterial pressure were analyzed for their effect on mortality, adjusting for other modifiers of risk, using Cox proportional hazards regression analysis of data collected from 6,781 patients randomized into the Studies of Left Ventricular Dysfunction trials. RESULTS: Pulse and mean arterial pressure were related positively to each other, age, ejection fraction and prevalence of diabetes and hypertension and inversely to prior myocardial infarction and beta-adrenergic blocking agent use. Higher pulse pressure was associated with increased prevalence of female gender, greater calcium channel blocking agent, digoxin and diuretic use, lower heart rate and a higher rate of reported smoking history. Higher mean arterial pressure was associated with higher heart rate, lower calcium channel blocker and digoxin use and lower New York Heart Association functional class. Over a 61-month follow-up 1,582 deaths (1,397 cardiovascular) occurred. In a multivariate analysis adjusting for the above covariates and treatment assignment, higher pulse pressure remained an independent predictor of total and cardiovascular mortality (total mortality relative risk, 1.05 per 10 mm Hg increment; 95% confidence interval, 1.01 to 1.10; p = 0.02). Mean arterial pressure was inversely related to total and cardiovascular mortality (total mortality relative risk, 0.89; 95% confidence interval, 0.85 to 0.94; p <0.0001). CONCLUSIONS: One noninvasive blood pressure measurement provides two independent prognostic factors for survival. Increased conduit vessel stiffness, as assessed by pulse pressure, may contribute to increased mortality in patients with left ventricular dysfunction, independent of mean arterial pressure.  (+info)

In vitro and in vivo comparison of three MR measurement methods for calculating vascular shear stress in the internal carotid artery. (3/1458)

BACKGROUND AND PURPOSE: Vascular abnormalities, such as atherosclerosis and the growth and rupture of cerebral aneurysms, result from a derangement in tissue metabolism and injury that are, in part, regulated by hemodynamic stress. The purpose of this study was to establish the feasibility and accuracy of determining wall shear rate in the internal carotid artery from phase-contrast MR data. METHODS: Three algorithms were used to generate shear rate estimates from both ungated and cardiac-gated 2D phase-contrast data. These algorithms were linear extrapolation (LE), linear estimation with correction for wall position (LE*), and quadratic extrapolation (QE). In vitro experiments were conducted by using a phantom under conditions of both nonpulsatile and pulsatile flow. The findings from five healthy volunteers were also studied. MR imaging-derived shear rates were compared with values calculated by solving the fluid flow equations. RESULTS: Findings of in vitro constant-flow experiments indicated that at one or two excitations, QE has the advantage of good accuracy and low variance. Results of in vitro pulsatile flow experiments showed that neither LE* nor QE differed significantly from the predicted value of wall shear stress, despite errors of 17% and 22%, respectively. In vivo data showed that QE did not differ significantly from the predicted value, whereas LE and LE* did. The percentages of errors for QE, LE, and LE* in vivo measurements were 98.5%, 28.5%, and 36.1%, respectively. The average residual of QE was low because the residuals were both above and below baseline whereas, on average, LE* tended to be a more biased overestimator of the shear rate in volunteers. The average and peak wall shear force in five volunteers was approximately 8.10 dyne/cm2 and 13.2 dyne/cm2, respectively. CONCLUSION: Our findings show that LE consistently underestimates the shear rate. Although LE* and QE may be used to estimate shear rate, errors of up to 36% should be expected because of variance above and below the true value for individual measurements.  (+info)

The pattern of changes in ovarian stromal and uterine artery blood flow velocities during in vitro fertilization treatment and its relationship with outcome of the cycle. (4/1458)

OBJECTIVES: To assess the effect of short-term (2-3 weeks) pituitary suppression and controlled ovarian stimulation on ovarian and uterine artery Doppler measurements during the in vitro fertilization (IVF) treatment cycle and to compare the pattern of these changes between conception and non-conception cycles as well as between patients with normal and those with polycystic ovaries. DESIGN: Prospective observational study of women undergoing IVF treatment. SUBJECTS: Women using the long-treatment buserelin protocol who did not have uterine fibroids, ovarian cysts or endometrioma. METHODS: Serial transvaginal color and pulsed Doppler measurements of ovarian stromal and uterine artery blood flow velocity were carried out in the early follicular phase of the menstrual cycle, on the day of pituitary suppression and on the day of administration of human chorionic gonadotropin (hCG). The main outcome measures were the ovarian stromal and uterine artery blood flow peak systolic velocity (PSV) and pulsatility index (PI). RESULTS: A total of 105 patients were recruited but six patients were excluded from the analysis because they had only one stage of the measurements performed. There was a significant decline in mean ovarian stromal artery PSV after 2-3 weeks of gonadotropin releasing hormone (GnRH) agonist therapy but no effect on ovarian stromal artery PI. The mean uterine artery PSV or PI did not change significantly after 2-3 weeks of GnRH agonist therapy. There was a significantly higher mean ovarian stromal artery PSV in conception cycles compared to non-conception cycles in the early follicular phase and on the day of pituitary suppression, but not on the day of hCG administration. There were no differences between conception and non-conception cycles in the mean uterine artery PSV or PI. Women with polycystic ovaries had a higher mean ovarian artery PSV on all the three occasions of measurement. CONCLUSION: These data suggest that assessment of ovarian blood flow before commencement of gonadotropin stimulation may play a role in assessing cycles likely to result in pregnancy.  (+info)

Characteristics of blood flow in intrauterine growth-restricted fetuses with hypercoiled cord. (5/1458)

OBJECTIVE: To clarify the characteristics of fetoplacental blood flow of growth-restricted fetuses with hypercoiled umbilical cord. SUBJECTS: Eight growth-restricted fetuses with hypercoiled cord. METHODS: Flow velocity waveforms of the umbilical cord artery and vein, fetal abdominal aorta and fetal inferior vena cava were analyzed. RESULTS: The resistance index in the umbilical artery in the hypercoiled cases was lower than that in normal fetuses. Early-diastolic reversed flow was observed in the abdominal aorta in some cases. In all cases, umbilical venous pulsation was observed in the entire cord until delivery. In one case, fetal heart failure occurred, resulting in pre-mature delivery. An atrophic type of single umbilical artery was observed in four cases. CONCLUSION: Fetal blood flow disturbance caused by a hypercoiled umbilical cord may be a cause of growth restriction.  (+info)

Pulmonary and caval flow dynamics after total cavopulmonary connection. (6/1458)

OBJECTIVE: To assess flow dynamics after total cavopulmonary connection (TCPC). DESIGN: Cross-sectional study. SETTING: Aarhus University Hospital. PATIENTS: Seven patients (mean age 9 (4-18) years) who had previously undergone a lateral tunnel TCPC mean 2 (0. 3-5) years earlier. INTERVENTIONS: Pressure recordings (cardiac catheterisation), flow volume, and temporal changes of flow in the lateral tunnel, superior vena cava, and right and left pulmonary arteries (magnetic resonance velocity mapping). RESULTS: Superior vena cava flow was similar to lateral tunnel flow (1.7 (0.6-1.9) v 1. 3 (0.9-2.4) l/min*m2) (NS), and right pulmonary artery flow was higher than left pulmonary artery flow (1.7 (0.6-4.3) v 1.1 (0.8-2. 5) l/min*m2, p < 0.05). The flow pulsatility index was highest in the lateral tunnel (2.0 (1.1-8.5)), lowest in the superior vena cava (0.8 (0.5-2.4)), and intermediate in the left and right pulmonary arteries (1.6 (0.9-2.0) and 1.2 (0.4-1.9), respectively). Flow and pressure waveforms were biphasic with maxima in atrial systole and late ventricular systole. CONCLUSIONS: Following a standard lateral tunnel TCPC, flow returning via the superior vena cava is not lower than flow returning via the inferior vena cava as otherwise seen in healthy subjects; flow distribution to the pulmonary arteries is optimal; and some pulsatility is preserved primarily in the lateral tunnel and the corresponding pulmonary artery. This study provides in vivo data for future in vitro and computer model studies.  (+info)

The effect of cold stress on uterine artery blood flow velocity waveforms in late pregnant women with and without preeclampsia. (7/1458)

Cold stimulus, immersing the hand into ice water, was given to pregnant women with and without preeclampsia. The uterine artery blood flow was observed before, during and after the stimulus by Doppler ultrasound. The pulsatility index in the uterine artery blood flow was significantly increased by the cold exposure in preeclampsia from 1.14 to 1.52, whereas it increased in normal control from 0.95 to 1.25. In two of 11 cases of preeclampsia with fetal growth restriction, cold stimulus to the mother elicited a decrease of variability on fetal heart rate monitoring. Cold stimulus induces the constriction of the uterine artery, leading to a decrease of placental blood flow.  (+info)

Transcranial color-coded duplex sonography of intracranial veins and sinuses in adults. Reference data from 130 volunteers. (8/1458)

BACKGROUND AND PURPOSE: Transcranial color-coded duplex sonography (TCCS) of intracranial veins and sinuses in adults is a new, emerging application of ultrasonographic imaging. This study reports a standardized examination protocol for venous TCCS and provides reference data for clinical application. METHODS: In 130 healthy volunteers (mean age, 45.9+/-16.9 years; range, 14 to 77 years) the intracranial venous system was examined using frequency-based transtemporal TCCS. Identification rate, blood flow velocity, resistance index, and systolic/diastolic ratio were recorded for each examined venous vessel. RESULTS: Intracranial veins and sinuses show a low pulsatile forward flow with maximal systolic blood flow velocity up to 20 cm/s. Significant side differences of blood flow velocity in the paired venous structures could not be detected. Venous flow velocities decreased with age, whereas resistance indices and systolic/diastolic ratios increased. Women showed higher flow velocities than men. Mean identification rates for all age groups ranged from 70% to 90% for the deep middle cerebral vein, the basal cerebral vein, and the great cerebral vein of Galen. The straight sinus, the transverse sinus, and the rostral part of the superior sagittal sinus could be detected in 55% to 70% of cases. Detection rates were dependent on age and decreased as age increased. CONCLUSIONS: Venous TCCS can reliably image a significant part of the cerebral venous system. This method can provide information on venous hemodynamics in normal subjects and pathological cases.  (+info)

Piezoelectric sensor determination of arterial pulse wave velocity<...Piezoelectric sensor determination of arterial pulse wave velocity<...
TY - JOUR. T1 - Piezoelectric sensor determination of arterial pulse wave velocity. AU - McLaughlin, JAD. AU - McNeill, MDJ. AU - Braun, B. AU - McCormack, PD. PY - 2003. Y1 - 2003. N2 - Arterial pulse wave velocity (APWV) is a measure of the elasticity (or stiffness) of peripheral arterial blood vessels. The pulse referred to here will be the pressure pulse as opposed to the flow pulse measured by ultrasound Doppler. The pressure pulse velocity varies over the range from about 12 m s−1 to 15 m s−1 in stiff peripheral arteries, whereas in normal arteries it has a velocity in the range of 7 to 9 m s−1.The aim of this project was the development of a fast and easy to use system for the determination of peripheral arterial pulse wave velocity. The principle of the PWV measurement is based on simultaneous measurement of two pulse waves at two different positions, such as the radial artery at the wrist and the brachial artery just above the elbow. By determining the pulse transit time between ...
https://pure.ulster.ac.uk/en/publications/piezoelectric-sensor-determination-of-arterial-pulse-wave-velocit-3
Effect of Panretinal Photocoagulation on Pulsatile Ocular Blood Flow in Patients With Proliferative Diabetic Retinopathy | IOVS...Effect of Panretinal Photocoagulation on Pulsatile Ocular Blood Flow in Patients With Proliferative Diabetic Retinopathy | IOVS...
Purpose: : To determine the effect of panretinal photocoagulation (PRP) on the pulsatile ocular blood flow (POBF) and the pulse amplitude (PA) in patients with proliferative diabetic retinopathy (PDR). Methods: : Twelve eyes of 12 patients with PDR who had undergone PRP were included. The POBF and the PA were measured with Langham OBF computerized tonometry system before, 1 month and 6 month after the last photocoagulation. Results: : The mean POBF and PA significantly (p,0.05) decreased 1 month (589.8 +/- 74.1 microlit/min and 1.26 +/- 0.23 mmHg) and 6 months (563.39 +/- 51.7 microlit/min and 1.08 +/- 0.10 mmHg) after PRP compared with those (770.2 +/- 90.2 microlit /min and 1.61 +/- 0.24 mmHg) before PRP. Conclusions: : This is the first study to examine the effect of PRP on pulsatile ocular blood flow using the Langham tonometer in patients with PDR. The present results that the mean PA and POBF decrease after PRP indicate that total choroidal blood flow may decrease in response to PRP. ...
https://iovs.arvojournals.org/article.aspx?articleid=2378151
flow pulsatility in cerebral veins - This Is MS Multiple Sclerosis Knowledge & Support Communityflow pulsatility in cerebral veins - This Is MS Multiple Sclerosis Knowledge & Support Community
Phase contrast MRI has been used to investigate flow pulsatility in cerebral arteries, larger cerebral veins and the cerebrospinal fluid. Such measurements of intracranial pulsatility and compliance are beginning to inform understanding of the pathophysiology of conditions including normal pressure hydrocephalus, multiple sclerosis and dementias. We demonstrate the presence of flow pulsatility in small cerebral cortical veins, for the first time using phase contrast MRI at 7 Tesla, with the aim of improving our understanding of the haemodynamics of this little-studied vascular compartment. An automated method for establishing where venous flow is pulsatile is introduced, revealing significant pulsatility in 116 out of 146 veins, across 8 healthy participants, assessed in parietal and frontal regions. Distributions of pulsatility index and pulse waveform delay were characterized, indicating a small, but statistically significant (p,0.05), delay of 59±41 ms in cortical veins with respect to the ...
https://www.thisisms.com/forum/viewtopic.php?t=31347
Resistance Training Augments Cerebral Blood Flow Pulsatility: Cross-Sectional Study<...
TY - JOUR. T1 - Resistance Training Augments Cerebral Blood Flow Pulsatility. T2 - Cross-Sectional Study. AU - Nakamura, Nobuhiro. AU - Muraoka, Isao. N1 - Publisher Copyright: © 2018 American Journal of Hypertension, Ltd. All rights reserved.. PY - 2018/6/11. Y1 - 2018/6/11. N2 - Background: Increased central arterial stiffness and/or decreased compliance reduces buffer function and increases cerebral blood flow (CBF) pulsatility, which leads to increased cerebral microvascular damage, resulting in the augmentation of the risk of cerebrovascular diseases. Resistancetrained men showed higher central arterial stiffness and lower arterial compliance than age-matched, sedentary men. This study examined the effect of increased central arterial stiffness and/or decreased arterial compliance on CBF pulsatility. Methods: The study participants included 31 young healthy men (15 resistancetrained men, aged 21 ± 1 years; and 16 controls, aged 23 ± 1 years). β-Stiffness index and arterial compliance ...
https://waseda.pure.elsevier.com/en/publications/resistance-training-augments-cerebral-blood-flow-pulsatility-cros
Effect of Smoking on Arterial Stiffness and Pulse Pressure Amplification | HypertensionEffect of Smoking on Arterial Stiffness and Pulse Pressure Amplification | Hypertension
We have shown a significant effect of smoking on large-artery properties. Acutely, cigarette smoking increased the AIx and PWV, suggesting an increase in arterial stiffness. Perhaps the most interesting finding was that young, otherwise healthy smokers have higher aortic systolic pressure and AIx compared with nonsmokers as the result of increased arterial wave reflection in the aorta, suggesting stiffer arteries. Decreased elasticity of such arteries is also suggested by the reduced pulse pressure amplification in chronic smokers.. The effect of acute cigarette smoking in healthy nonsmokers on forearm arterial hemodynamics showed an increase in BP, heart rate, and PWV.16 Acute cigarette smoking decreased arterial compliance in both large elastic and medium-sized muscular arteries.3,17 More recently, Stefanadis et al,5 using invasive methods, showed decreased aortic compliance acutely after smoking 1 cigarette in middle-aged men with coronary artery disease.. In the current study, AIx was ...
http://hyper.ahajournals.org/content/41/1/183.long
Comparison of different methods for the estimation of aortic pulse wave velocity from 4D flow cardiovascular magnetic resonance...Comparison of different methods for the estimation of aortic pulse wave velocity from 4D flow cardiovascular magnetic resonance...
Arterial pulse wave velocity (PWV) is associated with increased mortality in aging and disease. Several studies have shown the accuracy of applanation tonometry carotid-femoral PWV (Cf-PWV) and the relevance of evaluating central aorta stiffness using 2D cardiovascular magnetic resonance (CMR) to estimate PWV, and aortic distensibility-derived PWV through the theoretical Bramwell-Hill model (BH-PWV). Our aim was to compare various methods of aortic PWV (aoPWV) estimation from 4D flow CMR, in terms of associations with age, Cf-PWV, BH-PWV and left ventricular (LV) mass-to-volume ratio while evaluating inter-observer reproducibility and robustness to temporal resolution. We studied 47 healthy subjects (49.5 ± 18 years) who underwent Cf-PWV and CMR including aortic 4D flow CMR as well as 2D cine SSFP for BH-PWV and LV mass-to-volume ratio estimation. The aorta was semi-automatically segmented from 4D flow data, and mean velocity waveforms were estimated in 25 planes perpendicular to the aortic centerline.
https://jcmr-online.biomedcentral.com/articles/10.1186/s12968-019-0584-x
Effect of pulsatile flow on the Albumin permeability across the endothelial cell layer<...
TY - GEN. T1 - Effect of pulsatile flow on the Albumin permeability across the endothelial cell layer. AU - Kawarabayashi, Minoru. AU - Ikeda, Mariko. AU - Tanishita, Kazuo. PY - 2001. Y1 - 2001. N2 - The effect of pulsatile flow on the albumin permeability across the endothelial cell layer was discussed. The morphology and functions of the cells were affected by the external mechanical stimulus. It was found that the pulsation promoted the different mechano-transduction process from that of the steady flow.. AB - The effect of pulsatile flow on the albumin permeability across the endothelial cell layer was discussed. The morphology and functions of the cells were affected by the external mechanical stimulus. It was found that the pulsation promoted the different mechano-transduction process from that of the steady flow.. UR - http://www.scopus.com/inward/record.url?scp=0242693884&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0242693884&partnerID=8YFLogxK. M3 - Conference ...
https://waseda.pure.elsevier.com/en/publications/effect-of-pulsatile-flow-on-the-albumin-permeability-across-the-e
Arterial Pulse Wave Velocity and Cognition with Advancing Age
PubMed Central Canada (PMC Canada) provides free access to a stable and permanent online digital archive of full-text, peer-reviewed health and life sciences research publications. It builds on PubMed Central (PMC), the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature and is a member of the broader PMC International (PMCI) network of e-repositories.
http://pubmedcentralcanada.ca/pmcc/articles/PMC2716128/
OpenEmory | Search ResultsOpenEmory | Search Results
Total cavopulmonary connection is the result of a series of palliative surgical repairs performed on patients with single ventricle heart defects. The resulting anatomy has complex and unsteady hemodynamics characterized by flow mixing and flow separation. Although varying degrees of flow pulsatility have been observed in vivo, non-pulsatile (time-averaged) boundary conditions have traditionally been assumed in hemodynamic modeling, and only recently have pulsatile conditions been incorporated without completely characterizing their effect or importance. In this study, 3D numerical simulations with both pulsatile and non-pulsatile boundary conditions were performed for 24 patients with different anatomies and flow boundary conditions from Georgia Tech database. Flow structures, energy dissipation rates and pressure drops were compared under rest and simulated exercise conditions. It was found that flow pulsatility is the primary factor in determining the appropriate choice of boundary ...
https://open.library.emory.edu/publications/search/?keywords=cavopulmonari&keywords=engin&keywords=procedur&keywords=dynam&keywords=connect&keywords=pulsatil&keywords=total&keywords=simul&author=De+Zelicourt%2C+Diane&subject=Engineering%2C+Biomedical&year=2012
OpenEmory | Search ResultsOpenEmory | Search Results
Total cavopulmonary connection is the result of a series of palliative surgical repairs performed on patients with single ventricle heart defects. The resulting anatomy has complex and unsteady hemodynamics characterized by flow mixing and flow separation. Although varying degrees of flow pulsatility have been observed in vivo, non-pulsatile (time-averaged) boundary conditions have traditionally been assumed in hemodynamic modeling, and only recently have pulsatile conditions been incorporated without completely characterizing their effect or importance. In this study, 3D numerical simulations with both pulsatile and non-pulsatile boundary conditions were performed for 24 patients with different anatomies and flow boundary conditions from Georgia Tech database. Flow structures, energy dissipation rates and pressure drops were compared under rest and simulated exercise conditions. It was found that flow pulsatility is the primary factor in determining the appropriate choice of boundary ...
https://open.library.emory.edu/publications/search/?keywords=comput&keywords=cavopulmonari&keywords=engin&keywords=procedur&keywords=dynam&keywords=connect&keywords=pulsatil&keywords=total&journal=Journal+of+Biomechanical+Engineering&subject=Engineering%2C+Biomedical&author=De+Zelicourt%2C+Diane&author=Yoganathan%2C+Ajit&department=BME:%20Admin
Abstract 355: Calculating Pulse Wave Velocity from a Single Pressure Waveform Using the Intrinsic Frequency Method |...Abstract 355: Calculating Pulse Wave Velocity from a Single Pressure Waveform Using the Intrinsic Frequency Method |...
INTRODUCTION: Increased aortic stiffness is correlated with many clinically adverse cardiovascular outcomes. The gold standard quantitative index for arterial stiffness is the pulse wave velocity (PWV). We have developed a new method called the Intrinsic Frequency (IF), which views the arterial pressure waveform as a piecewise combination of two coupled systems, the heart and arterial system which are decoupled upon closure of the aortic valve. Each of these dynamical systems has an inherent frequency of operation (ω1 and ω2) which gives information about LV function (ω1) as well as arterial dynamics (ω2).. METHODS: IF methodology is based on Sparse Time-Frequency Representation method. It uses an effective L2-minimization to extract the second intrinsic frequency (ω2) from an aortic pressure waveform. To examine the clinical relevance of this method, IF was applied to aortic pressure waveforms taken from published works. These aortic waveforms were selected from a healthy population free ...
http://hyper.ahajournals.org/content/64/Suppl_1/A355
Atcor Central Pressure & Pulse Wave Velocity
AtCor Medical lead the world in the field of arterial pulse wave analysis and velocity systems. The SphygmoCor range provide tools for non-invasive assessment of the cardiovascular system and autonomic function.. Sphygmocor technology is based on a transfer function that derives the pressure wave at the ascending aorta. This transfer function is a patented algorithm of the properties of the brachial artery, providing important central data from a non-invasive recording of the pressure wave at the radial artery. SphygmoCor allows the physician to assess the cardiovascular state of the patient, where it really matters - at the heart. ...
http://www.smartmedical.co.uk/products/categories/atcor-central-pressure-pulse-wave-velocity
A Novel Interpretation for Arterial Pulse Pressure Amplification in Health and DiseaseA Novel Interpretation for Arterial Pulse Pressure Amplification in Health and Disease
The Journal of Healthcare Engineering is a peer-reviewed, Open Access journal publishing fundamental and applied research on all aspects of engineering involved in healthcare delivery processes and systems. It provides a vehicle for the exchange of advanced knowledge, emerging technologies, and innovative ideas among healthcare engineering researchers, engineers, managers, and consultants around the world.
https://www.hindawi.com/journals/jhe/2018/1364185/
MR-Gated Intracranial CSF Dynamics: Evaluation of CSF pulsatile flow | Springer for Research & DevelopmentMR-Gated Intracranial CSF Dynamics: Evaluation of CSF pulsatile flow | Springer for Research & Development
Magnetic resonance imaging (MRI) was used to evaluate cerebrospinal fluid (CSF) pulsatile flow in eleven patients with hydrocephalus and three normal subjects. Multislice images were acquired using...
https://rd.springer.com/chapter/10.1007/978-3-662-11158-1_28
Calculations of pulsatile flow through a branch: implications for the hemodynamics of atherogenesis. | Circulation ResearchCalculations of pulsatile flow through a branch: implications for the hemodynamics of atherogenesis. | Circulation Research
Numerical simulations of pulsatile blood flow through a symmetrical branch modeling the aortic bifurcation were carried out to assess several hemodynamic theories of atherogenesis by comparing the distribution of hemodynamic variables with that of early lesions in arterial branches. Considerable spatial and temporal variations in wall shear were found when the flow was pulsatile; the highest values occurred at the convex corner on the outer wall of the branch and in the neighborhood of the flow divider tip, and the lowest shears were experienced by the outer wall of the daughter vessel a short distance distal to the corner. Transient flow reversal occurred almost everywhere in the branch, and a transient separated region was found corresponding to the low-shear region in the daughter vessel. The shear profiles and the calculated separated region were influenced to some degree by the extent of flow development at the branch inlet and markedly by the branch area ratio. All of the proposed ...
http://circres.ahajournals.org/content/36/2/277
Safety and Tolerability of MK-5478 in Participants With Hypertension (5478-001) - Full Text View - ClinicalTrials.govSafety and Tolerability of MK-5478 in Participants With Hypertension (5478-001) - Full Text View - ClinicalTrials.gov
Central blood pressure (CBP) parameters will be measured and used to derive the aortic augmentation index (AIx). The AIx quantifies the contribution of back-reflected outgoing systolic pressure waves to late-systolic central blood pressure, which increases with decreasing aortic compliance. AIx is measured by pulse wave analysis using the SphygmoCor System supplied by AtCor Medical. Results with a , 5% decrease in AIx were planned for analysis; results with a , 5% decrease in AIx were not analysed ...
https://clinicaltrials.gov/show/NCT01025843
Magnetic resonance imaging of pulse wave velocity in children aged 9 years to assess maternal influences on aortic stiffness in...
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https://www.ndorms.ox.ac.uk/publications/313068
Pulsatile blood flow and lipolysis in human adipose tissue - Radcliffe Department of MedicinePulsatile blood flow and lipolysis in human adipose tissue - Radcliffe Department of Medicine
We use cookies to ensure that we give you the best experience on our website. If you click Continue well assume that you are happy to receive all cookies and you wont see this message again. Click Find out more for information on how to change your cookie settings ...
https://www.rdm.ox.ac.uk/publications/30457
Ocular Rigidity, Outflow Facility, Ocular Pulse Amplitude, and Pulsatile Ocular Blood Flow in Open-Angle Glaucoma: A Manometric...Ocular Rigidity, Outflow Facility, Ocular Pulse Amplitude, and Pulsatile Ocular Blood Flow in Open-Angle Glaucoma: A Manometric...
Purpose.: To compare ocular rigidity (OR) and outflow facility (C) coefficients in medically treated open-angle glaucoma (OAG) patients and controls, and to investigate differences in ocular pulse amplitude (OPA) and pulsatile ocular blood flow (POBF) between the two groups. Methods.: Twenty-one OAG patients and 21 controls undergoing cataract surgery were enrolled. Patients with early or moderate primary or pseudoexfoliative OAG participated in the glaucoma group. A computer-controlled system, consisting of a pressure transducer and a microstepping device was employed intraoperatively. After cannulation of the anterior chamber, IOP was increased by infusing the eye with microvolumes of saline solution. IOP was recorded after each infusion step. At an IOP of 40 mm Hg, an IOP decay curve was recorded for 4 minutes. OR coefficients, C, OPA, and POBF were estimated from IOP and volume recordings. Results.: There were no differences in age or axial length in the two groups. The OR coefficient was ...
http://iovs.arvojournals.org/article.aspx?articleid=2127862
Patent US8229530 - System and method for detection of venous pulsation - Google PatentsPatent US8229530 - System and method for detection of venous pulsation - Google Patents
In accordance with an embodiment of the present technique, there is provided methods and systems for detecting the presence of venous pulsation by adjusting the sensitivity of a detection algorithm based on a sensor characteristic and/or notifying a caregiver of the presence of venous pulsation by ceasing display of physiological parameters. An exemplary embodiment includes receiving one or more signals from a sensor, the one or more signals corresponding to absorption of light in a patients tissue; calculating one or more physiological parameters of the patient based on the one or more signals; displaying the patients physiological parameters; enabling detection of venous pulsation with variable sensitivity based on a location of the sensor; and suspending or terminating the display of the one or more of the patients physiological parameters when venous pulsation is detected.
http://www.google.ca/patents/US8229530
Effect of methionine loading on pulse wave analysis in elderly volunteers | Postgraduate Medical JournalEffect of methionine loading on pulse wave analysis in elderly volunteers | Postgraduate Medical Journal
Objective: To test the hypothesis that an acute increase in plasma homocysteine produced by methionine is associated with an acute increase in pulse wave velocity.. Design: A double blind, cross over, placebo controlled design was used and pulse wave velocity, plasma homocysteine, total cholesterol: high density lipoprotein ratio, plasma triglyceride, oxidised low density lipoprotein cholesterol concentrations, apolipoproteins A1 and B, and C reactive protein were measured between 12.5 and 20 hours after methionine loading or placebo.. Results: Between 12.5 and 20 hours after exposure to a methionine loading test, arterial pulse wave velocity showed no significant difference compared with placebo. At 12 hours after exposure to the methionine loading test, in the presence of a controlled diet, triglyceride concentration significantly increased by 32.6% (p,0.02), cholesterol: high density lipoprotein ratio increased significantly by 22.5% (p,0.05) compared with placebo. Simultaneously, systolic ...
http://pmj.bmj.com/content/82/970/524
EFFECT OF PULSATILE FLOW ON RENAL FUNCTION IN ELDERLY PATIENTS UNDERGOING CORONARY ARTERY BYPASS SURGERY
Abstract The incidence of acute kidney injury (AKI) after on-pump coronary artery bypass graft (CABG) varies among studies but can be reduced if pulsatile flow is used. The aim of this study is to evaluate pulsatile flow impact on renal function of elderly patients undergoing CABG. Over one year (April 2014 to April 2015) 48 patients above the age of 65 underwent on-pump CABG in our institute. Patients were divided into two groups; pulsatile flow (PFG) and non-pulsatile flow (NPFG) groups. Serum creatinine (S.Cr), creatinine clearance (Cr.Cl) and per-perfusion urine output (UO) were measured. AKI Network criteria were adopted for diagnosis. Mean age was 68 in PFG and 69 in NPFG. Males constituted 83.3% of PFG and 79.2% of NPFG. Although 37.5% of PFG and 41.7% of NPFG were hypertensive, all patients had normal ejection fraction (EF). Both groups had nearly 3 coronary anastomoses, cardiopulmonary bypass (CPB) time of 90 min, cross clamp time of 71 min and mean perfusion pressure of 70 mmHg. Mean
https://bjsrg.uobasrah.edu.iq/article_164515.html
Influence of Aortic Coarctation on Pulsatile Hemodynamics in the Proximal Aorta | CirculationInfluence of Aortic Coarctation on Pulsatile Hemodynamics in the Proximal Aorta | Circulation
Pressure and flow were recorded in the ascending aorta of three dogs with aortic coarctation, induced surgically 3 months previously, and in three control litter mates. From these data were derived input impedance of the systemic circulation, pulsatile and steady components of external heart work, aortic systolic pressure-time index, and mean systolic and mean diastolic pressures. Results were correlated with intraoperative measurements of aortic pressure in three young patients with aortic coarctation and with records taken in another 24 patients during diagnostic catheterization. Distinctive changes in aortic impedance with coarctation were explained in terms of altered peripheral reflection. Such changes were responsible for characteristic alteration in central aortic pressure pulse contour and for change in other parameters, indicating impaired arterial function in accepting pulsatile flow from the heart. Such changes in the cushioning function appear responsible for many clinical features ...
http://circ.ahajournals.org/content/44/2/281
SphygmoCor® CVMSSphygmoCor® CVMS
The SphygmoCor® CP System The SphygmoCor CP system includes pulse wave analysis (PWA) software only. During a PWA measurement, a 10-second snapshot of the radial arterial pressure wave is measured using a tonometer. The SphygmoCor software derives the ascending aortic pressure wave, substantially equivalent to the pressure wave measured by an invasive catheter. From the aortic pressure wave, a number of valuable cardiovascular measurements are determined, including central aortic systolic pressure, aortic augmentation index and central pulse pressure ...
https://www.einstinc.com/wpcproduct/sphygmocor-cvms/
Association of a pulsatile blood flow pattern on coronary arteriography and short-term clinical outcomes in acute myocardial...Association of a pulsatile blood flow pattern on coronary arteriography and short-term clinical outcomes in acute myocardial...
This study demonstrates that a pulsatile pattern of coronary blood flow is associated with impaired myocardial perfusion and poorer clinical outcomes. Prior studies have demonstrated that impaired epicardial blood flow, LAD culprit artery location, and multivessel or left main disease are all angiographic variables that are associated with poorer clinical outcomes after fibrinolytic administration for acute STEMI (1,14-18). This study extends these observations to demonstrate that a pulsatile pattern of epicardial blood flow is also associated with adverse clinical outcomes. A pulsatile flow pattern was associated with higher incidence of death or recurrent MI at 30 days even after adjusting for other confounding variables. In a multivariate model adjusting for previously identified correlates of angiographic reocclusion (14)(TFG, LAD, thrombus, percent diameter stenosis, eccentric lesion, ulcerated lesion, or collaterals) and clinical reinfarction (15)(PCI and age), the presence of pulsatile ...
http://www.onlinejacc.org/content/43/7/1170
jafmonline.net - Abstracts of Accepted Papers before Proofjafmonline.net - Abstracts of Accepted Papers before Proof
Arteriovenous fistula (AVF) is the most widely used vascular access by patients undergoing hemodialysis, however, even though the most widely used access to AVF has a high failure rate, and can be affected by problems during its use, among the most common highlights intimal hyperplasia, thrombosis and stenosis. Studies suggest that recurrent problems in this type of access are directly linked to geometry, flow conditions and stiffness of the vascular wall by the vessels that compose it. The present work seeks to analyze the variation of pressure and flow in rigid and flexible AVF models manufactured from data from an actual patient undergoing treatment. The study was carried out from the acquisition and processing of the patients medical examinations (computed tomography), the creation of the geometry, treatment and modeling of said patient, the manufacturing of the AVF models by 3D printing and injection in mold, experimental analysis with pulsatile flow conditions, close to the real ...
https://jafmonline.net/web/guest/39?p_p_id=AcceptedPaper_WAR_AcceptedPaper&p_p_action=0&p_p_state=normal&p_p_mode=view&p_p_col_id=column-1&p_p_col_count=1&_AcceptedPaper_WAR_AcceptedPaper_form_page=paper_details&paperidParam=32182&typeIdParam=85&paper_status=ACCEPTED
pulsatile flow pump Manufacturers and Suppliers China - Wholesale - Trandomedpulsatile flow pump Manufacturers and Suppliers China - Wholesale - Trandomed
Buy quality pulsatile flow pump for sale with Trandomed - one of the leading manufacturers and suppliers in this field. We provide professional training and samples for all customers if you need. Also, the online wholesale service is also available with cheap price.
http://www.trando-med.com/product/pulsatile-flow-pump.html
Sex differences in resting hemodynamics and arterial stiffness following 4 weeks of resistance versus aerobic exercise training...Sex differences in resting hemodynamics and arterial stiffness following 4 weeks of resistance versus aerobic exercise training...
The results from this study suggest that AE has different effects on the cardiovascular system of men and women. The majority of studies assessing the effects of exercise training on BP and arterial function have been conducted in single-sex or mixed-sex populations, but without direct comparisons between the sexes [13-17]. To our knowledge, the present study is the first to directly compare differences between the sexes in the effects of exercise mode on resting hemodynamic parameters and variables of arterial stiffness in an unmedicated hypertensive cohort. The major novel finding of our study was that RE resulted in increases in central arterial stiffness in men, but not in women (Figure 1a,b). Conversely, AE produced a decrease in central arterial stiffness but no change in peripheral arterial stiffness for either sex. Another novel finding was that compared with AE, RE resulted in a greater increase in basal and peak FBF in both men and women (Figure 2a,b).. Several studies support our ...
https://bsd.biomedcentral.com/articles/10.1186/2042-6410-2-9
Pulsatile Flow Effects on the Hemodynamics of Intracranial Aneurysms | Journal of Biomechanical Engineering | ASME DCPulsatile Flow Effects on the Hemodynamics of Intracranial Aneurysms | Journal of Biomechanical Engineering | ASME DC
and the pulsatility index (PI) are systematically varied within the human physiologic range. We show that the waveform PI is the key parameter that governs the vortex dynamics across the aneurysm neck and the flow patterns within the dome. At low PI, the flow in the dome is similar to a driven cavity flow and is characterized by a quasi-stationary shear layer that delineates the parent artery flow from the recirculating flow within the dome. At high PI, on the other hand, the flow is dominated by vortex ring formation, transport across the neck, and impingement and breakdown at the distal wall of the aneurysm dome. We further show that the spatial and temporal characteristics of the wall shear stress field on the aneurysm dome are strongly correlated with the vortex dynamics across the neck. We finally argue that the ratio between the characteristic time scale of transport by the mean flow across the neck and the time scale of vortex ring formation can be used to predict for a given sidewall ...
http://biomechanical.asmedigitalcollection.asme.org/article.aspx?articleid=1427508
Precise quantification of pressure-flow waveforms during pulsatile and nonpulsatile perfusion<...
TY - JOUR. T1 - Precise quantification of pressure-flow waveforms during pulsatile and nonpulsatile perfusion. AU - Ji, Bingyang. AU - Undar, Akif. N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.. PY - 2007/5. Y1 - 2007/5. UR - http://www.scopus.com/inward/record.url?scp=34247496402&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=34247496402&partnerID=8YFLogxK. U2 - 10.1016/j.jtcvs.2006.10.076. DO - 10.1016/j.jtcvs.2006.10.076. M3 - Letter. C2 - 17467484. AN - SCOPUS:34247496402. VL - 133. SP - 1395. JO - Journal of Thoracic and Cardiovascular Surgery. JF - Journal of Thoracic and Cardiovascular Surgery. SN - 0022-5223. IS - 5. ER - ...
https://pennstate.pure.elsevier.com/en/publications/precise-quantification-of-pressure-flow-waveforms-during-pulsatil
Features » UscomFeatures » Uscom
Central BP has been shown to more strongly reflect vascular disease and predict outcomes than traditional upper arm BP. Central BP can also determine the different effects of different hypertension medications when upper arm BP and pulse wave velocity do not. Central BP is the pressure that the heart has to pump against to get blood to flow to the rest of the body. Higher central BP means that the heart consumes more energy to pump blood. This can eventually lead to heart failure. Central BP also reflects the pressure in the blood vessels feeding the brain. If central BP is high, it this may lead to aneurysms and strokes.. Augmentation Index. The augmentation index is a ratio calculated from the pulse pressure waveform, and is a measure of wave reflection and arterial stiffness. Augmentation index is commonly accepted as a measure of the (augmentation) of central aortic pressure by a reflected pulse wave.. ...
http://uscom.com.au/products/bp/features/
Most recent papers with the keyword cardiac flow rate | Read by QxMDMost recent papers with the keyword cardiac flow rate | Read by QxMD
Cardiovascular diseases are the leading cause of death worldwide. Pulse wave analysis (PWA) technique, which reconstructs and analyses aortic pressure waveform based on non-invasive peripheral pressure recording, became an important bioassay for cardiovascular assessment in a general population. The aim of our study was to establish a pulse wave propagation modeling framework capable of matching clinical PWA data from healthy individuals on a per-subject basis. Radial pressure profiles from 20 healthy individuals (10 males, 10 females), with mean age of 42 ± 10 years, were recorded using applanation tonometry (SphygmoCor, AtCor Medical, Australia) and used to estimate subject-specific parameters of mathematical model of blood flow in the system of fifty-five arteries ...
https://www.readbyqxmd.com/keyword/25679
Most recent papers with the keyword virtual scenario | Read by QxMDMost recent papers with the keyword virtual scenario | Read by QxMD
Cardiovascular diseases are the leading cause of death worldwide. Pulse wave analysis (PWA) technique, which reconstructs and analyses aortic pressure waveform based on non-invasive peripheral pressure recording, became an important bioassay for cardiovascular assessment in a general population. The aim of our study was to establish a pulse wave propagation modeling framework capable of matching clinical PWA data from healthy individuals on a per-subject basis. Radial pressure profiles from 20 healthy individuals (10 males, 10 females), with mean age of 42 ± 10 years, were recorded using applanation tonometry (SphygmoCor, AtCor Medical, Australia) and used to estimate subject-specific parameters of mathematical model of blood flow in the system of fifty-five arteries ...
https://www.readbyqxmd.com/keyword/8740
Plus itPlus it
The performance standards for equipment are as follows (table 2⇓). 1) The volume-measurement accuracy should be the same as that established by the ATS/ERS for spirometry 49; that is, ±3% volume accuracy (±3.5% accounting for 0.5% testing syringe error) over an 8-L volume range with test gases present in concentrations likely to be encountered during DL,CO tests. Pneumotachometer devices for sensing flow and volume during the DL,CO manoeuvre may be sensitive to different gas compositions, concentrations or pulsatile flow changes created by demand valves 50. All devices should maintain the required volume accuracy, regardless of the gas mixture, direction of gas flow (e.g. inhaled or exhaled), or pulsatile flow pattern. 2) Gas-analyser accuracy is important in some circumstances, such as measuring CO back pressure (the expired fraction of CO when no CO has been inhaled). However, in calculating DL,CO, only the ratios of alveolar to inhaled CO and tracer gas are needed. Thus, the analysers ...
https://erj.ersjournals.com/content/26/4/720
PPT - The Arterial System PowerPoint Presentation - ID:797283PPT - The Arterial System PowerPoint Presentation - ID:797283
The Arterial System. The Windkessel Effect Arterial Pressure Determinants CO TPR Changes in the Pulse Waveform. The hydraulic filter converts pulsatile flow to steady flow. Hydraulic filtering converts the intermittent output of the heart to a steady flow through the capillaries....
https://www.slideserve.com/albert/the-arterial-system
One-dimensional computational model of pulse wave propagation in the human bronchial tree. - Radcliffe Department of MedicineOne-dimensional computational model of pulse wave propagation in the human bronchial tree. - Radcliffe Department of Medicine
Airflow in the respiratory system has been predominantly studied in rigid ducts. Three-dimensional simulations are computationally expensive. One-dimensional (1-D) modelling offers a good compromise between accuracy and computational cost. In this work we described the propagation of air pulse in a model of human airways using the 1-D equations of flow in compliant vessels. Seven generations of bifurcations, starting from the trachea, were studied. Peripheral airways (from the 8(th) to 23(rd) generation) were modelled using lumped parameter models. Peripheral resistance values for normal and emphysematous lungs were taken from the literature. An acceleration pulse, very short in time, was enforced at the inlet of trachea. The results suggest that compression (positive pressure peaks) and expansion (negative pressure peaks) waves are generated according to the reflection coefficients of the corresponding reflection sites (bifurcations and terminal reflections). Different values for peripheral bronchial
https://www.rdm.ox.ac.uk/publications/564128
PPT - Chapter 1- General Properties of Waves Reflection Seismology Geol 4068 Elements of 3D Seismology , 2nd Edition by Christ...PPT - Chapter 1- General Properties of Waves Reflection Seismology Geol 4068 Elements of 3D Seismology , 2nd Edition by Christ...
Chapter 1- General Properties of Waves Reflection Seismology Geol 4068 Elements of 3D Seismology , 2nd Edition by Christopher Liner August 25, 2005 . Outline-I. General Properties of Waves Mechanical definition of a wave Physical Assumptions Wave descriptions Body waves Slideshow...
https://www.slideserve.com/december/chapter-1-general-properties-of-waves-reflection-seismology-geol-4068-elements-of-3d-seismology-2nd-edition-by-christo
Non-invasive assessment of wave reflection phenomena in the central aorta<...Non-invasive assessment of wave reflection phenomena in the central aorta<...
TY - JOUR. T1 - Non-invasive assessment of wave reflection phenomena in the central aorta. AU - Avolio, Alberto. AU - Cook, David. AU - Old, R. AU - Halliday, A. PY - 2002. Y1 - 2002. M3 - Conference paper. SP - 895. EP - 895. JO - Journal of Hypertension. T2 - Journal of Hypertension. JF - Journal of Hypertension. SN - 1473-5598. ER - ...
https://researchers.mq.edu.au/en/publications/non-invasive-assessment-of-wave-reflection-phenomena-in-the-centr
EUR/USD Elliott Wave Analysis: 3 Year Chart Pattern Nears an EndEUR/USD Elliott Wave Analysis: 3 Year Chart Pattern Nears an End
EUR/USD Elliott Wave analysis shows a three year expanded flat pattern is nearing an end. We are anticipating a bearish reversal that begins from a
https://www.dailyfx.com/forex/technical/elliott_wave/eur-usd/2018/01/11/3-year-pattern-concluding.html?DFXfeeds=forex:technical:elliott_wave:eur-usd
Equities : The Truth About Elliott Wave AnalysisEquities : The Truth About Elliott Wave Analysis
This evening, one of my members forwarded me a public post made by another analyst about Elliott Wave analysis, which seemed to be supported by his novice acolytes. And, yes, that perspective...
http://www.4-traders.com/news/Equities-The-Truth-About-Elliott-Wave-Analysis--25254446/
Pre-Clinical TestingPre-Clinical Testing
The MiTiHeart® LVAD has been extensively evaluated in both in vitro and in vivo animal studies. The LVAD system has been successfully subjected to more than 5,000 hours of in vitro testing and 2,000 hours of animal implant testing. The latest MiTiHeart® LVAD system is compact, efficient and capable of long-term stable operation in vitro and in vivo. A total input power of 6 W was required at a design point of 4,100 rpm while pumping 5 L/min against 100 mmHg. This is among the lowest power reported by magnetically levitated LVADs found in literature. In Vitro testing showed low hemolysis under non-pulsatile and pulsatile conditions. NIH values are among the lowest reported in literature. Long-term durability testing has been demonstrated for 63 days of continuous operation while submerged in saline. Two successful chronic implant studies were performed. In both studies, the MiTiHeart® LVAD operated as expected with no device related complications. Recent test results will allow the MiTiHeart® ...
http://mitiheart.com/pre-clinical-testing/4556678444
View of Variation in carotid-femoral pulse wave velocity, augmentation pressure and augmentation index during different phases...View of Variation in carotid-femoral pulse wave velocity, augmentation pressure and augmentation index during different phases...
Kahkashan N et al authored manuscript titled Variation in carotid-femoral pulse wave velocity, augmentation pressure and augmentation index during different phases of menstrual cycle
http://amphysiol.com/index.php/amp/article/view/v2i3.10454/49
Influence of sprint exercise on aortic pulse wave velocity and femoral artery shear patterns<...
TY - JOUR. T1 - Influence of sprint exercise on aortic pulse wave velocity and femoral artery shear patterns. AU - DeBlois, Jacob P.. AU - Lefferts, Wesley K.. AU - Heffernan, Kevin S.. PY - 2020. Y1 - 2020. N2 - Purpose: Aortic stiffness may affect shear patterns in the peripheral vasculature. This study examined if sprint exercise, which typically increases aortic stiffness is associated with increased peripheral retrograde blood flow and impaired microvascular function. Methods: Twenty participants (10 women; age: 27 ± 5 years) underwent arterial stiffness, shear rate, and microvascular function assessment at three time points: baseline; following time control; ~ 2 min post a 30-s cycle ergometer sprint against 7.0% body mass. Aortic stiffness was assessed using carotid-femoral pulse wave velocity (cfPWV). Superficial femoral artery (SFA) diameter and blood velocity were assessed using Doppler-ultrasound and were used to calculate shear rates and resistance index (RI). SFA wave reflections ...
https://experts.syr.edu/en/publications/influence-of-sprint-exercise-on-aortic-pulse-wave-velocity-and-fe
Aortic Pulse Wave Velocity (PWVao) - Pulse Wave Analysis & Arterial StiffnessAortic Pulse Wave Velocity (PWVao) - Pulse Wave Analysis & Arterial Stiffness
Measurement of aortic Pulse Wave Velocity (PWVao) provides some of the strongest evidence concerning the prognostic significance of large artery stiffening
https://www.tensiomed.com/parameters/aortic-pulse-wave-velocity-pwvao/
The Impact of Cardiovascular Risk Factors on Aortic Stiffness and Wave Reflections Depends on Age
Ageing exerts differential effects on arterial stiffness and wave reflections. However, the impact of cardiovascular risk factors on arterial stiffness and wave reflections and, particularly, how such effects are influenced by ageing has not been assessed within a single large population, covering a sufficiently wide age range. Therefore, we determined the extent to which age alters the impact of traditional cardiovascular risk factors on arterial stiffness and wave reflections. Aortic stiffness and wave reflections were assessed in 4421 individuals (age range 18 to 92 years). When treated as continuous variables, clinic systolic, diastolic, and pulse pressures and glucose levels were independently associated with stiffness, and, with the exception of diastolic pressure, these associations were more marked in older individuals. In contrast, clinic systolic and diastolic pressures and smoking were independently associated with wave reflections, with stronger associations observed in younger ...
https://repository.cardiffmet.ac.uk/handle/10369/5451
Diastolic augmentation index improves radial augmentation index in assessing arterial stiffnessDiastolic augmentation index improves radial augmentation index in assessing arterial stiffness
Arterial stiffness is an important risk factor for cardiovascular events. Radial augmentation index (AI r ) can be more conveniently measured compared with carotid-femoral pulse wave velocity (cfPWV). However, the performance of AI r in assessing arterial stiffness is limited. This study proposes a novel index AI rd , a combination of AI r and diastolic augmentation index (AI d ) with a weight α, to achieve better performance over AI r in assessing arterial stiffness. 120 subjects (43 ± 21 years old) were enrolled. The best-fit α is determined by the best correlation coefficient between AI rd and cfPWV. The performance of the method was tested using the 12-fold cross validation method. AI rd (r = 0.68, P , 0.001) shows a stronger correlation with cfPWV and a narrower prediction interval than AI r (r = 0.61, P , 0.001), AI d (r = −0.17, P = 0.06), the central augmentation index (AI c ) (r = 0.61, P , 0.001) or AI c normalized for heart rate of 75 bpm (r = 0.65, P , 0.001). Compared with AI r ...
https://www.tue.nl/publicatie/ep/p/d/ep-uid/81120443-5682-4c5a-9750-38d37dfc8cf6/
Abstract P054: A Novel Index of Insulin Resistance and Segment-specific Pulse Wave Velocity: The Atherosclerosis Risk in...Abstract P054: A Novel Index of Insulin Resistance and Segment-specific Pulse Wave Velocity: The Atherosclerosis Risk in...
Background: Carotid-femoral pulse wave velocity (cfPWV) is a reference measure of central (elastic) artery stiffness and a risk factor for cardiovascular disease. Femoral-ankle pulse wave velocity (faPWV) is a measure of peripheral (musculo-elastic) arterial stiffness. The ratio of fasting triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) is a novel and practical marker of insulin resistance (IR), a dysregulation that often precedes diabetes. While diabetes is a known risk factor for arterial stiffening, associations of IR with segment-specific measures of PWV, in those without diabetes, have not been well characterized.. Objective: To characterize the cross-sectional association of IR, as indexed by TG/HDL-C, with central and peripheral arterial stiffness by race and gender in older adults without diagnosed diabetes. We hypothesized that TG/HDL-C is positively associated with cfPWV and inversely associated with faPWV.. Methods: Our study population included 2477 white and 564 ...
http://circ.ahajournals.org/content/133/Suppl_1/AP054
Arterial stiffness progressively associated with duration of type 2 diabetes mellitus in overweight & obese male population of...Arterial stiffness progressively associated with duration of type 2 diabetes mellitus in overweight & obese male population of...
Many studies show pathophysiological link between Type 2 Diabetes(T2DM), CardioVascular Diseases (CVD) and Arterial Stiffness. In this cross-section study 60 male Overweight, Obese adult patients of various durations of T2DM, 25to65 years age, of Western Rajasthan are examined for the arterial stiffness. Brachial-ankle Pulse Wave Velocities (BrAnkPWV) and carotid to femoral Pulse Wave Velocity (cfPWV) were taken as indices of central arterial stiffness. Brachial and ankle Arterial Stiffness Indexes (ASI) are taken as indices for corresponding local arterial stiffness. These parameters were measured by an automated oscillometric based device Periscope. Smokers and history of vascular diseases were excluded. Results stratified in groups of duration of T2DM, ,5 years, 6to 10 years and ,10years and compared. Regressions of PWVs and ASI on duration of T2DM were analysed unadjusted and adjusted for age, BMI and Blood Pressure. cfPWV, RBrAnkPWV & LBrAnkPWV are significantly higher in group of longer ...
http://journalijcar.org/issues/arterial-stiffness-progressively-associated-duration-type-2-diabetes-mellitus-overweight
Reference values of aortic pulse wave velocity in a large healthy population aged between 3 and 18 years<...
TY - JOUR. T1 - Reference values of aortic pulse wave velocity in a large healthy population aged between 3 and 18 years. AU - Reusz, George S.. AU - Shroff, Rukshana. AU - Kis, Eva. AU - Cseprekal, Orsolya. AU - Fischer, Dagmar Christiane. AU - Haffner, Dieter. PY - 2013/2/1. Y1 - 2013/2/1. UR - http://www.scopus.com/inward/record.url?scp=84872866782&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=84872866782&partnerID=8YFLogxK. U2 - 10.1097/HJH.0b013e32835c021f. DO - 10.1097/HJH.0b013e32835c021f. M3 - Letter. C2 - 23303358. AN - SCOPUS:84872866782. VL - 31. SP - 424. EP - 425. JO - Journal of Hypertension. JF - Journal of Hypertension. SN - 0263-6352. IS - 2. ER - ...
https://hungary.pure.elsevier.com/en/publications/reference-values-of-aortic-pulse-wave-velocity-in-a-large-healthy
Missing information in determining reference values of aortic pulse wave velocity in the elderly - Ajaums RepositoryMissing information in determining reference values of aortic pulse wave velocity in the elderly - Ajaums Repository
Khoshdel, Ali R and Carney, Shane L (2009) Missing information in determining reference values of aortic pulse wave velocity in the elderly. Journal of Hypertension, 27 (6). pp. 1329-1330. ISSN 0263-6352 ...
http://eprints.ajaums.ac.ir/183/
Pulsatile Flow Behavior in Elastic Systems Containing Wave Reflection Sites | Journal of Fluids Engineering | ASME DCPulsatile Flow Behavior in Elastic Systems Containing Wave Reflection Sites | Journal of Fluids Engineering | ASME DC
Copyright in the material you requested is held by the American Society of Mechanical Engineers (unless otherwise noted). This email ability is provided as a courtesy, and by using it you agree that you are requesting the material solely for personal, non-commercial use, and that it is subject to the American Society of Mechanical Engineers Terms of Use. The information provided in order to email this topic will not be used to send unsolicited email, nor will it be furnished to third parties. Please refer to the American Society of Mechanical Engineers Privacy Policy for further information ...
http://fluidsengineering.asmedigitalcollection.asme.org/article.aspx?articleid=1434207
Circulatory, Vascular and Cardiac sub-cluster 57
Carotid-femoral pulse wave velocity (cf-PWV) is a validated marker of arterial stiffening over the central arteries. Brachial-ankle pulse wave velocity (ba-PWV) integrates the mechanical properties from both the central and peripheral arteries and may be more representative than cf-PWV as arterial load for left ventricle (LV). We compared ba-PWV with ...
http://www.biomedsearch.com/cluster/26/Circulatory-Vascular-and-Cardiac/sub-57-p2.html
Nonpulsatile cardiopulmonary bypass disrupts the flow-metabolism couple in the brain<...
TY - JOUR. T1 - Nonpulsatile cardiopulmonary bypass disrupts the flow-metabolism couple in the brain. AU - Andersen, K.. AU - Waaben, J.. AU - Husum, B.. AU - Voldby, B.. AU - Bødker, A.. AU - Hansen, A. J.. AU - Gjedde, A.. PY - 1985. Y1 - 1985. N2 - The effect of cardiopulmonary bypass on the relationship between brain glucose consumption and regional blood flow is unknown. We measured this relationship in pigs subjected to 3 hours of pulsatile or nonpulsatile cardiopulmonary bypass at normothermia and compared the results to the relationship established in a control group of pigs. A total of 10 regions were sampled in both hemispheres of the porcine brain. In control pigs, cerebral blood flow averaged 46 ml/100 gm and the glucose consumption, 21 μmol/100 gm/min. The ratio between blood flow and glucose consumption was close to 2 ml/μmol in all regions. In pulsatile cardiopulmonary bypass both the whole-brain average and the regional values declined, so that the ratio remained the same, ...
https://jhu.pure.elsevier.com/en/publications/nonpulsatile-cardiopulmonary-bypass-disrupts-the-flow-metabolism--5
VENTRICULAR AND ARTERIAL DYNAMICS OF ANAESTHETISED AND SWIMMING TUNA | Journal of Experimental BiologyVENTRICULAR AND ARTERIAL DYNAMICS OF ANAESTHETISED AND SWIMMING TUNA | Journal of Experimental Biology
Cardiovascular dynamics of tuna have been investigated by recording blood pressures and flows in the central circulation of both anaesthetised and swimming individuals. In anaesthetised fish (N=5), heart rate averaged 112+/−21 beats min-1 (mean +/− s.e.) and stroke volume was 0.67+/−0.24 ml kg-1 when normoxic water flowed over the gills. Ventricular diastolic pressure was zero until atrial contraction filled the ventricle. Ventral aortic pressures were high (mean 12.08+/−1.15 kPa), and blood flow was continuous in the ventral aorta throughout diastole. Dorsal aortic pressure (mean 6.3+/−1.28 kPa; N=4) and flow were both pulsatile. Pressure pulsatility (pulse pressure as a proportion of mean pressure) was about one-quarter of flow pulsatility, indicating considerable compliance in the dorsal aortic circulation. Total peripheral resistance averaged 0.17+/−0.4 kPa ml-1 kg-1 min-1 of which gill resistance averaged 48+/−15 % (N=4). For the ventral aorta, impedance modulus fell markedly ...
http://jeb.biologists.org/content/182/1/97.short
Whey Protein Isolate May Favorably Alter Cardiovascular Function in Older Adults - mackieshilstone.com
Based on research into the various paths the Covid-19 disease can track in the human body, its apparent that the entire body-from the inflammation in the brain to swelling (redness) in the toes-can be affected.. Its also recognized that people over the age of 65-especially those with comorbidities, such as hypertension, diabetes, cardiovascular, liver, and kidney disease, are at greater risk to complications, if the disease gains a foothold in the lungs.. With advanced age, there is also an inherent risk, without early lifestyle intervention, to vascular dysfunction-specifically arterial stiffness. In essence, the arteries become stiffer, which involves structural and functional changes-leading to cardiovascular and cerebrovascular disease.. Stiff arteries can lead to buffering changes in large, central arteries and increases in blood pressure, and blood flow pulsatility, comment researchers from the Human Performance Laboratory at Syracuse University in New York, who published Effects of ...
http://www.mackieshilstone.com/whey-protein-isolate-may-favorably-alter-cardiovascular-function-in-older-adults/
Virtual database
While central (carotid-femoral) foot-to-foot pulse wave velocity (PWV) is considered to be the gold standard for the estimation of aortic arterial stiffness, peripheral foot-to-foot PWV (brachial-ankle, femoral-ankle, carotid-radial) are being studied as substitutes of this central measurement. We present a novel methodology to assess theoretically these computed indices and the hemodynamics mechanisms relating them. We created a database of 3320 virtual healthy adult subjects using a validated one-dimensional model of the arterial hemodynamics, with cardiac and arterial parameters varied within physiological healthy ranges. For each virtual subject, foot-to-foot PWV were computed from numerical pressure waveforms at the same locations where clinical measurements are commonly taken. Our results confirm clinical observations: (i) carotid-femoral PWV is a good indicator of aortic stiffness, and correlates well with aortic PWV; (ii) brachial-ankle PWV over-estimates aortic PWV and is related to the ...
http://haemod.uk/virtual-database
Intermittent versus constant aerobic exercise in middle-aged males: acute effects on arterial stiffness and factors influencing...
TY - JOUR. T1 - Intermittent versus constant aerobic exercise in middle-aged males. T2 - acute effects on arterial stiffness and factors influencing the changes. AU - Peres, D.. AU - Mourot, L.. AU - Ménétrier, A.. AU - Bouhaddi, M.. AU - Degano, B.. AU - Regnard, J.. AU - Tordi, N.. PY - 2018/8/1. Y1 - 2018/8/1. N2 - Purpose: Both constant and intermittent acute aerobic exercises have been found to decrease arterial stiffness. However, direct comparisons of these two types of exercise are sparse. It is not known which type of exercise has the greatest effect. Methods: We evaluated the haemodynamic responses in 15 males (age 48.5 ± 1.3 years; BMI 27.5 ± 0.8 kg m−2) following acute constant (CE) and intermittent cycling exercise (IE). Duration and heart rate were matched during both exercises (131.8 ± 3.2 bpm for CE and 132.0 ± 3.1 bpm for IE). Central and peripheral arterial stiffness was assessed through pulse wave velocity (PWV). Plasma concentrations of nitric oxide (NO), atrial ...
https://tpu.pure.elsevier.com/en/publications/intermittent-versus-constant-aerobic-exercise-in-middle-aged-male
Pulsatile blood flow, shear force, energy dissipation and Murrays LawPulsatile blood flow, shear force, energy dissipation and Murrays Law
A cellular mechanism that senses shear force at the inner wall of a blood vessel and triggers remodeling that increases the circumference of the wall when a shear force threshold is exceeded would result in the observed scaling of vessel radii described by Murrays Law.
https://pubmed.ncbi.nlm.nih.gov/16923189/
Withings reintroduces Pulse Wave Velocity Measurement on £129 Body Cardio Scales - ShinyShinyWithings reintroduces Pulse Wave Velocity Measurement on £129 Body Cardio Scales - ShinyShiny
Digital healthcare brand Withings has announced the reintroduction of Pulse Wave Velocity (PWV) measurements on its Body Cardio connected scales in Europe
https://www.shinyshiny.tv/2019/04/withings-reintroduces-pulse-wave-velocity-measurement-on-129-body-cardio-scales.html?shared=email&msg=fail
Arterial Remodeling Associates with CKD Progression | American Society of NephrologyArterial Remodeling Associates with CKD Progression | American Society of Nephrology
We showed that arterial remodeling evolutes overtime with an enlargement and a thinning of the carotid artery, leading to an increased carotid circumferential wall stress. This kind of arterial remodeling evolution is unusual in this high cardiovascular risk population. The pathophysiology of increased carotid circumferential wall stress is not obvious. In response to increased BP, in particular, the pulsatile component, degenerative changes, and fractures of the extracellular matrix component occur in the arterial wall, leading to arterial enlargement.14 The response to dilation is a thickening of the arterial wall, generally considered as adaptive, aiming at normalizing circumferential wall stress. We have previously shown in hypertensive patients that local pulse pressure was associated with increased diameter and intima-media thickness; however, circumferential wall stress was not fully normalized.15 In this study, we showed that this response does not occur in CKD patients and instead we ...
https://jasn.asnjournals.org/content/22/5/967?ijkey=682d786ed25e8bdd1bbacdfd6d7873af1c252e10&keytype2=tf_ipsecsha
Pulmonic Arterial System and AfterloadPulmonic Arterial System and Afterload
The pulmonary arteries have a relatively high-density of alpha-1 receptors [Rudner XL et al. Circulation 100: 2336, 1999], second only to hepatic/omental arteries. The pulmonary arteries also contains alpha receptors [Troncy E et al. Br J Anaesth 79: 631, 1997; Blaise G et al. Anesthesiology 99: 1415, 2003]. Therefore, it should be assumed that alpha-agonists can profoundly increase RV afterload.. While pulmonary vascular resistance is ~ 20% of SVR, pulmonary vascular impedance is 50% of systemic vascular impedance. The difference in the two is most likely related to the increased intensity of pulse wave reflections in the pulmonary vascular tree (impedance is related to vascular resistance, vascular compliance, and wave reflections, all of which oppose pulsatile blood flow) [Barash, PG. Clinical Anesthesia, 5th ed. (Philadelphia), p. 882, 2006]. Because SVR is such a poor indicator of afterload [Lang RM et al. Circulation 74: 1114, 1986], it may follow that PVR does not accurately predict ...
http://www.openanesthesia.org/pulmonic_arterial_system_and_afterload/
Download Arterial Stiffness: Implications and Interventions by Bradley S. Fleenor, Adam J. Berrones PDF - Gomad Festival BooksDownload Arterial Stiffness: Implications and Interventions by Bradley S. Fleenor, Adam J. Berrones PDF - Gomad Festival Books
Tanaka H, DeSouza CA, Seals DR (1998) Absence of age-related increase in central arterial stiffness in physically active women. Arterioscler Thromb Vasc Biol 18(1):127-132 52. Zhu W, Hooker SP, Sun Y, Xie M, Su H, Cao J (2014) Associations of cardiorespiratory fitness with cardiovascular disease risk factors in middle-aged Chinese women: a cross-sectional study. BMC Womens Health 14:62. 1186/1472-6874-14-62 53. Quan HL, Blizzard CL, Sharman JE, Magnussen CG, Dwyer T, Raitakari O, Cheung M, Venn AJ (2014) Resting heart rate and the association of physical fitness with carotid artery stiffness. 07 m/s per year [26]. In summary, arterial stiffness increases linearly until approximately 50 years of age, after which time there is an acceleration of the stiffening process. Sex Due to sex related differences in CVD incidence, prevalence, morbidity and mortality [27], it is important to discuss the influence of sex on the progression of arterial stiffness. For example, discrepancies exist between sexes ...
http://gomadfestival.com/library/arterial-stiffness-implications-and-interventions
Abstract TP190: Bone Mineral Density is Inversely Related to Cerebral Pulsatility Index in Patients With Acute Ischemic Stroke ...Abstract TP190: Bone Mineral Density is Inversely Related to Cerebral Pulsatility Index in Patients With Acute Ischemic Stroke ...
Introduction: Atherosclerosis and osteoporosis are two major public health problems. These are both multifactorial and degenerative diseases that accompany aging. Co-morbidities are common, with a high prevalence of cardiovascular risk factors including hypertension, smoking, and sedentary lifestyle. Several studies have suggested a relationship between atherosclerosis and osteoporosis, with a significant correlation between coronary artery calcium and bone mineral density (BMD). The pulsatility index (PI) is designed to measure vascular resistance and characterizes the shape of the spectral waveform. The PI was increasing with age but alterations in PI are the reflection of multifactorial, pleiotropic events occurring in the cardio and cerebral vascular system. Atherosclerosis of the large proximal arteries and the intracranial vessels are important factors for increased PI.. Hypothesis: We hypothesized that the transcranial Doppler (TCD) PI would reflect the atherosclerotic component of ...
http://stroke.ahajournals.org/content/47/Suppl_1/ATP190
Greater in vivo than in vitro pulsatility of insulin secretion with synchronized insulin and somatostatin secretory pulsesGreater in vivo than in vitro pulsatility of insulin secretion with synchronized insulin and somatostatin secretory pulses
To examine the control of pulsatile insulin secretion by an intrapancreatic pacemaker, samples at minute intervals were taken from the portal vein in dogs in vivo and from an isolated perfused pancreas preparation in vitro. Anesthetized dogs had high amplitude pulsatile insulin secretion which was n …
https://pubmed.ncbi.nlm.nih.gov/2883001/?dopt=Abstract
GRP78 Upregulation by Atheroprone Shear Stress Via p38-, α2β1-Dependent Mechanism in Endothelial Cells | Arteriosclerosis,...GRP78 Upregulation by Atheroprone Shear Stress Via p38-, α2β1-Dependent Mechanism in Endothelial Cells | Arteriosclerosis,...
We present evidence for the differential control of hemodynamics in influencing EC expression of GRP78, an ER chaperone responsible for alleviating cell toxicity and a key regulator of the UPR. To our knowledge, this is the first instance of GRP78 protein expression to be mechanically responsive, and further is differentially regulated in atheroprone versus atheroprotective regions in vivo and regulated by shear stress in a waveform specific manner in vitro. The mechanisms by which atheroprone flow induces increases in GRP78 were dependent on p38 activity and α2β1. The differential regulation of GRP78 protein and the ERSE activation by the onset of atheroprone flow signify the induction of the UPR and its sustained activity. Inflammatory cytokines found in atheroprone environments had no effect on GRP78 expression in ECs, and its regulation by known chemical agonists was independent of the p38 and α2β1 pathways. This result further accentuates the prominence of shear stress patterns in the ...
http://atvb.ahajournals.org/content/28/8/1534
Asian Science Citation Index - Articles written by Jorge A. BassukAsian Science Citation Index - Articles written by Jorge A. Bassuk
Introduction: Periodic acceleration (pGz) is a non-invasive method of increasing pulsatile shear stress to the endothelium. pGz is achieved by the sinusoidal head to foot motion to the supine body. pGz increases endogenous production of nitric oxide in whole animal models and isolated perfused vessel preparations, and is cardioprotective when applied prior to, during and after ischemia reperfusion. In part, the protective effects of pGz are attributable to nitric oxide (NO). The purpose of this investigation was to determine whether pGz up-regulates NOS isoforms in the endomyocardium. Methods and results: Fifteen swine weight 15-20kg, were anesthetized, instrumented to measure hemodynamics and randomized. Ten animals received 1h of pGz at 180cycles/min and Gz±3.9m/s2 [pGz] in addition to conventional ventilatory support and five served as time controls. Results: pGz produced a 2.3±0.4 and a 6.6±0.1 fold significant increase in eNOS and phosphorylated eNOS, 3.6±1.1 fold increase in nNOS, and ...
https://scialert.net/asci/author.php?ascicat=ALL&author=Jorge&last=A.%20Bassuk
Association of Intracranial Pressure and Spontaneous Retinal Venous Pulsation - UCL DiscoveryAssociation of Intracranial Pressure and Spontaneous Retinal Venous Pulsation - UCL Discovery
UCL Discovery is UCLs open access repository, showcasing and providing access to UCL research outputs from all UCL disciplines.
https://discovery.ucl.ac.uk/id/eprint/10081436/
EFFECf OF TI-IE NON-NEWTONIAN VISCOSITY OF BLOOD ON STEADY AND PULSATILE FLOW IN STENOSED ARTERIES - ...
University of Cincinnati , Department of Mechanical and Materials Engineering 2600 Clifton Ave., Cincinnati, Ohio 45221 , Phone 513 556 2738 ...
http://www.min.uc.edu/rbanerje/conferences-trial/1991/EFFECf%20OF%20TI-IE%20NON-NEWTONIAN%20VISCOSITY%20OF%20BLOOD%20ON%20STEADY%20AND%20PULSATILE%20FLOW%20IN%20STENOSED%20ARTERIES.pdf/view
2D Computational Fluid Dynamic Modeling of Human Ventricle System Based on Fluid-Solid Interaction and Pulsatile Flow - Basic...2D Computational Fluid Dynamic Modeling of Human Ventricle System Based on Fluid-Solid Interaction and Pulsatile Flow - Basic...
BCN is the official Publication of Neuroscience Departments of Tehran University of Medical Sciences and Shahid Beheshti University of Medical Sciences. BCN is an international multidisciplinary journal that publishes editorials, original full‐length research articles, short communications, reviews, methodological papers, commentaries, perspectives and
http://bcn.iums.ac.ir/browse.php?a_id=347&sid=1&slc_lang=fa
WATERS IGL® PULSATILE PERFUSION SOLUTION - Waters Medical Systems
WATERS IGL® Pulsatile Perfusion Solution has a calculated potassium concentration of 25 mEq/L, a sodium concentration of 100 mEq/L, an osmolarity of 300 mOsM, and a pH of 7.4 at room temperature. Its ion composition is comparable with that of the intracellular milieu. ...
https://wtrs.com/waters-igl-pulsatile-perfusion-solution/
Pulse-Wave Analysis | Arteriosclerosis, Thrombosis, and Vascular BiologyPulse-Wave Analysis | Arteriosclerosis, Thrombosis, and Vascular Biology
This study describes the effects of albuterol and NTG on the aortic pressure waveform. AIx, a quantitative index of systemic arterial stiffness,9 was calculated from aortic waveforms generated by PWA.10 Our main novel findings are that albuterol and NTG produce qualitatively and quantitatively similar and repeatable effects on AIx, that the effect of albuterol but not of NTG is inhibited by LNMMA and reduced in hypercholesterolemic subjects, and that the response to albuterol is correlated with the effect of ACh in the forearm vascular bed. These data indicate that the effect of albuterol is, in part, NO and endothelium dependent and are constistent with the presence of endothelial dysfunction in hypercholesterolemic subjects. Moreover, they suggest that PWA and administration of albuterol and NTG provide a simple, reliable, noninvasive method for assessing endothelial function, as we and others have previously hypothesized.23,24. As expected, inhalation of albuterol at the dose used reduced AIx ...
http://atvb.ahajournals.org/content/22/1/147
The aims of our study were to identify the risk factors | Beneficial Effects of RAF Inhibitor iThe aims of our study were to identify the risk factors | Beneficial Effects of RAF Inhibitor i
p=0.02). There were no significant differences between the two groups for gender, BMI, the number of smokers, medication of ACEI or ARB, the period of dialysis, the adequacy of dialysis (Kt/V), the values of the hematocrit, total cholesterol, triglyceride, LDL-cholesterol, phosphorus, the products of calcium and phosphorus, iPTH, the average MAP, DBP and HR and the echocardiographic parameters, except for the LVMi. Table 1 The main characteristics of the patient populace at baseline according to the groups of aortic pulse wave velocity Association between AoPWV and clinical parameters Pearsons correlation test was performed to examine the associations between AoPWV and the clinical parameters. The AoPWV value was positively correlated with age (r=0.40, p=0.01), the presence of diabetes (r=0.27, p=0.04), the serum calcium (r=0.31, p=0.02), the hs-CRP (r=0.38, p=0.01), the average pulse pressure (r=0.38, p=0.01), the LVMi (r=0.24, p=0.03) and the LAD (r=0.22, p=0.04), but the AoPWV value was ...
http://biodiversityhotspot.org/2017/09/the-aims-of-our-study-were-to-identify-the-risk-factors/
Patent US6120456 - Apparatus for measuring pulse-wave propagation velocity - Google PatentsPatent US6120456 - Apparatus for measuring pulse-wave propagation velocity - Google Patents
An apparatus for measuring a propagation velocity of a pulse wave which is propagated through an artery of a living subject, the apparatus including an electrocardiographic-waveform detecting device which detects an electrocardiographic waveform from the subject, a pulse-wave sensor which is adapted to be worn on the subject and which detects the pulse wave from the subject, a time-difference determining device for determining a time difference between a first periodic point relating to the detected electrocardiographic waveform and a second periodic point relating to the detected pulse wave, and a propagation-velocity determining means for determining the propagation velocity of the pulse wave based on the determined time difference.
http://www.google.com/patents/US6120456?dq=system+for+measuring+web+traffic&ei=Lg8FT__TIIr-sQKzxaGRCg
Roger P. Vermilion, M.D. - University of Rochester Medical CenterRoger P. Vermilion, M.D. - University of Rochester Medical Center
Jo, CO.; Lande, MB.; Meagher, CC.; Wang, H.; Vermilion, RP. A Simple Method of Measuring Thoracic Aortic Pulse Wave Velocity in Children: Methods and Normal Values. American Society of Echocardiography. 2010; 23(7): 735-740. ...
https://www.urmc.rochester.edu/people/23061897-roger-p-vermilion
Pulse Wave Analysis | Advanced Rejuvenation Institute
-------------------------------------------------------------------------------------------------------------------------------- *** SPECIAL NOTE FROM...
http://advancedrejuvenationinstitute.com/cardiovascular/pulse-wave-analysis.html
My Pharmacy: About viagra tabletten without prescription!My Pharmacy: About viagra tabletten without prescription!
Future problems of childhood. Frame was extracted from the heart, fully traversing the left and right pulmonary artery pulsatility index and middle finger along the septum, findings in normal individuals, lv enddiastolic pressure. Rychik j etal. American college of radiology in their abilities, in older infants and children (american academy of pediatrics. An essential characteristic is transferred from the diet. Baschat aa, gembruch u. Prenat diagn 2011;26:2659. Other risk factors and prognosis for ulcerative colitis have similar 1year patency to svg, but very rarely develops in ~9% of these contexts, in the childs behavior in adolescents (approximately 17%). Svc pressure ultimately increases and ra pressure and poststenotic dilatation). Early clinical manifestations of hearing impairment involves mainly interference with normal ef and total colonic aganglionosis in hirschsprung disease. It is advisable for all parties; include as many senses as possible to assess the hidden p waves and go ...
https://plastic-pollution.org/trialrx/about-viagra-tabletten/31/
FAQ | Naturopath Brisbane | Olea HealthFAQ | Naturopath Brisbane | Olea Health
Dr Ross Walker - Cardiologist For the past 25 years, newer technologies have been researched and introduced in the detection of heart disease, a central one being Pulse Wave Analysis (PWA). PWA is a simple, non-invasive test that measures each pulse emanating from the heart. This is conveniently measured at the wrist, thus not requiring disrobing, lying down or exercise. The computer then takes the information detected at the wrist and converts it (via a process known as a transfer function) to a central pulse. From the central pulse information, small and large vessel stiffness is measured and this has been shown in numerous studies to be an accurate predictor for future cardiac risk. Cholesterol, blood pressure, cigarette smoking, diabetes and family history are frequently used to evaluate the risk of cardiovascular disease. However, over the past decades there have emerged newer, more accurate screening techniques that have a much greater predictive value than traditional methods. Although ...
https://oleahealth.com.au/faq/
iVAC2L™ - Percutaneous ventricular assist device
With a percutaneous femoral approach, iVAC2L can support with a pulsatile flow patients with impaired left ventricular function who require a mechanical circula
https://www.terumo-europe.com/en-emea/interventional-cardiology/coronary-intervention-products/percutaneous-ventricular-assist-device/ivac2l%E2%84%A2-percutaneous-ventricular-assist-device
The Pressure Flow ModelThe Pressure Flow Model
Great simulation explaining how the pressure flow model works in plants, good voice tutorial, online, easy to display with a pro-board or a projector. This site has an introduction, animation, conclusion, and quiz to better understand the topic. ...
https://www.merlot.org/merlot/viewMaterial.htm?id=765109
Identify two (2) variables needed to promote the accuracy of pulse oximetry results in the newborn. Discuss why these variables...Identify two (2) variables needed to promote the accuracy of pulse oximetry results in the newborn. Discuss why these variables...
One variable needed to promote accuracy of pulse oximetry results is the babys condition. When analyzing the baby for a pulsatile flow, there is a need for sufficient perfusion in the area being monitored. In this case, if the baby has weak or absent peripheral pulse, the reading from the pulse oximetry will often not be preci. ...
https://www.qualifiedwriters.com/samples/identify-two-2-variables-needed-to-promote-the-accuracy-of-pulse-oximetry-results-in-the-newborn-discuss-why-these-variables-are-important-to-address/
Heart Disease the Silent Kiwi Killer - CellworksHeart Disease the Silent Kiwi Killer - Cellworks
At Cellworks we have developed the Executive Health Assessment- making use of the latest in pathology markers, genetic testing, and blood pressure pulse wave analysis.
https://www.cellworks.co.nz/heart-disease-the-silent-kiwi-killer/
The respiratory time and flow profile at volitional exercise termination. Gross cycling efficiency is not altered with and...The respiratory time and flow profile at volitional exercise termination. Gross cycling efficiency is not altered with and...
The respiratory time and flow profile at volitional exercise termination. Gross cycling efficiency is not altered with and without toe-clips
http://www.readabstracts.com/Sports-and-fitness/The-respiratory-time-and-flow-profile-at-volitional-exercise-termination.html
Sponsors and Links - VBPS
We are proud to announce an annual award, given by S+BmedVET: We would like to encourage interested veterinarians from all over the world to contribute to a better understanding of blood pressure and pulse wave analysis (PWA) including but not limited to pharmacologic modelling.(read more ,,) ...
https://www.vbps-online.com/sponsors-and-links/
Return to the www.schiller.ch home pageReturn to the www.schiller.ch home page
The first 300 units CARDIOVIT AT-102 G2 have already been shipped. The instructions are taking place, as here in Finland with some of the Mehiläinen nurses. The Mehiläinen decision makers reveal the devices key qualities they wanted to adopt in their nationwide institution.. ...
https://www.schiller.ch/sy/en
Monitoring of Pressure Pulsations in the Hydraulic System of the Stator Current Signature Induction Machine | BUT Digital...Monitoring of Pressure Pulsations in the Hydraulic System of the Stator Current Signature Induction Machine | BUT Digital...
This paperis focused on monitoring and evaluation of pressure pulsations in the hydraulic system, which includes a hydrodynamic pump. The entire system is driven by an induction machine. The goal of this paper is to accurately determine pressure pulsations by measurement of elecrical variables of an induction machine ...
https://dspace.vutbr.cz/handle/11012/43007?show=full
PULSE WAVE MEASURING APPARATUS MANUFACTURED WITH SUPPRESSED COST - OMRON HEALTHCARE Co., Ltd.PULSE WAVE MEASURING APPARATUS MANUFACTURED WITH SUPPRESSED COST - OMRON HEALTHCARE Co., Ltd.
A pulse wave measuring apparatus includes a pump (|b|9|/b|) and a three-port valve (|b|10|/b|). The pump (|b|9|/b|) includes an exhaust port (|b|91|/b|) and an intake port (|b|92|/b|), and performs an
https://www.freepatentsonline.com/y2009/0030329.html
How Does Perfusion Affect The Body? - laconsultoracorp.com
PI is an indicator of the relative strength of the pulsatile signal from pulse oximetry and has been found to be a reliable indicator of peripheral perfusion. PI is calculated by dividing the pulsatile signal (AC) by the nonpulsatile signal (DC) times 100, and is expressed as a percent ranging from 0.02% to 20 ...
https://laconsultoracorp.com/qa/how-does-perfusion-affect-the-body.html
A modelling study of evolving particle-laden turbulent pipe-flowA modelling study of evolving particle-laden turbulent pipe-flow
An Eulerian turbulent two phase flow model in cylindrical coordinates was developed in order to study evolving turbulent gas particle flows in a downward pipe flow. The model takes the feedback of the particles into account. Simulations shows good agreement with experiments and showed that the pipe length required for particle laden turbulent pipe flow to become fully developed is four times longer than for unladen flows, even for rather low mass loadings. The accumulation of particles in the near wall region showed a nonmonotonic behaviour and was found to be strongest for St=0.5.. ...
http://kth.diva-portal.org/smash/record.jsf?pid=diva2:680524
Pulsatile flowPulsatile flow
In fluid dynamics, a flow with periodic variations is known as pulsatile flow, or as Womersley flow. The flow profiles was ... The cardiovascular system of chordate animals is a very good example where pulsatile flow is found, but pulsatile flow is also ... The pulsatile flow profile is given in a straight pipe by u ( r , t ) = R e { ∑ n = 0 N i P n ′ ρ n ω [ 1 − J 0 ( α n 1 / 2 i 3 ... The pressure gradient driving the pulsatile flow is decomposed in Fourier series, ∂ p ∂ x ( t ) = ∑ n = 0 N P n ′ e i n ω t ...
https://en.wikipedia.org/wiki/Pulsatile_flow
Ventricular assist deviceVentricular assist device
2007). "Comparisons of infection complications between continuous flow and pulsatile flow left ventricular assist devices". The ... and continuous-flow pumps. Pulsatile VADs use positive displacement pumps. In some pulsatile pumps (that use compressed air as ... less frequent adverse events and greater reliability with continuous flow LVADS compared to pulsatile flow devices. Of the 281 ... Continuous-flow VADs are smaller and have proven to be more durable than pulsatile VADs. They normally use either a centrifugal ...
https://en.wikipedia.org/wiki/Ventricular_assist_device
Berlin HeartBerlin Heart
EXCOR is a paracorporeal, pulsatile flow VAD. The device provides left ventricular, right ventricular or biventricular ... INCOR is an axial-flow pump for support of the left ventricle. In this system, the pump is implanted directly next to the heart ... The blood coming from the heart flows into the INCOR axial pump. The rotor in the pump has an active magnetic bearing while ... Like the heart, EXCOR blood pumps have valves which ensure that the blood only flows in one direction. The blood pumps are ...
https://en.wikipedia.org/wiki/Berlin_Heart
PhotoplethysmogramPhotoplethysmogram
In particular, wide-field imaging of pulsatile motion induced by blood flow can be measured on the thumb by digital holography ... Bencteux J, Pagnoux P, Kostas T, Bayat S, Atlan M (June 2015). "Holographic laser Doppler imaging of pulsatile blood flow". ... and achieve high temporal resolution and full-field imaging capability of pulsatile blood flow. Heart rate monitor Clitoral ... Because blood flow to the skin can be modulated by multiple other physiological systems, the PPG can also be used to monitor ...
https://en.wikipedia.org/wiki/Photoplethysmogram
Holographic interferometryHolographic interferometry
It can be used for pulsatile blood flow imaging. Electronic speckle pattern interferometry Holography Interferometry Powell RL ... "Pulsatile microvascular blood flow imaging by short-time Fourier transform analysis of ultrafast laser holographic ... "Holographic laser Doppler imaging of pulsatile blood flow". Journal of Biomedical Optics. 20 (6): 066006. arXiv:1501.05776. ... It can also be used to detect optical path length variations in transparent media, which enables, for example, fluid flow to be ...
https://en.wikipedia.org/wiki/Holographic_interferometry
Sigma approximationSigma approximation
Recktenwald, Steffen M.; Wagner, Christian; John, Thomas (2021-06-29). "Optimizing pressure-driven pulsatile flows in ...
https://en.wikipedia.org/wiki/Sigma_approximation
ThoratecThoratec
... and greater reliability with continuous-flow LVADs compared to pulsatile-flow devices. As of mid 2015, Thoratec has the only ... The material is currently[when?] used in the Thoratec PVAD pulsatile-flow biventricular device. By 2000, the Thoratec VAD ... In a two-year randomized controlled clinical trial published in 2009 comparing pulsatile and continuous-flow LVADs, survival ... The technology is for use in a minimally invasive, acute cardiac axial-flow pump that can be delivered percutaneously in a ...
https://en.wikipedia.org/wiki/Thoratec
Dimensionless numbers in fluid mechanicsDimensionless numbers in fluid mechanics
Bookbinder; Engler; Hong; Miller (May 2001). "Comparison of Flow Measure Techniques during Continuous and Pulsatile Flow". 2001 ... Petritsch, G.; Mewes, D. (1999). "Experimental investigations of the flow patterns in the hot leg of a pressurized water ... Science Applications International Corporation (2001). Performing Quality Flow Measurements at Mine Sites. Washington, DC: U.S ... flow speed, etc. As a general example of how dimensionless numbers arise in fluid mechanics, the classical numbers in transport ...
https://en.wikipedia.org/wiki/Dimensionless_numbers_in_fluid_mechanics
Murrays lawMurray's law
Painter, Page R; Edén, Patrik; Bengtsson, Hans-Uno (2006). "Pulsatile blood flow, shear force, energy dissipation and Murray's ... Since flow is leakless, the total flow rate into a junction must be the total flow rate out: ∑ in Q = ∑ out Q . {\displaystyle ... Although most derivations of Murray's law assume a steady state flow field, the same results apply for flow in tubes that have ... If network flow is smooth and leak-free, then systems that obey Murray's law minimize the resistance to flow through the ...
https://en.wikipedia.org/wiki/Murray's_law
Kleibers lawKleiber's law
doi:10.1111/j.1365-2435.2006.01136.x. Painter PR, Edén P, Bengtsson HU (August 2006). "Pulsatile blood flow, shear force, ... Because fluid flow through a tubule is determined by the volume thereof, the total fluid flow is proportional to the total ... metabolism should scale proportionally to nutrient flow (or, equivalently, total fluid flow) in this circulatory system and (2 ... Thus, if B denotes the basal metabolic rate, Q the total fluid flow, and N the number of minimal tubules, B ∝ Q ∝ N . {\ ...
https://en.wikipedia.org/wiki/Kleiber's_law
Samuel Z. CardonSamuel Z. Cardon
Iberall, Arthur S.; Cardon, Samuel Z.; Young, Ed, On Pulsatile and Steady Arterial Flow - The GTS Contribution., Upper Darby, ... Effect of oxygen on cyclic red blood cell flow in unanesthetized mammalian striated muscle as determined by spectroscopy. ...
https://en.wikipedia.org/wiki/Samuel_Z._Cardon
Tesla valveTesla valve
Nguyen, Quynh M.; Abouezzi, Joanna; Ristroph, Leif (17 May 2021). "Early turbulence and pulsatile flows enhance diodicity of ... the flow rate. The diodicity is then the ratio of the reversed flow resistance to the forward flow resistance: D i = R r R f {\ ... is the reverse flow pressure drop, and Δ p f {\displaystyle \Delta p_{\rm {f}}} the forward flow pressure drop for flow rate Q ... This difference in flow resistance causes a net directional flow rate in the forward direction in oscillating flows. The ...
https://en.wikipedia.org/wiki/Tesla_valve
Pipe flowPipe flow
Nguyen, Quynh M.; Abouezzi, Joanna; Ristroph, Leif (17 May 2021). "Early turbulence and pulsatile flows enhance diodicity of ... Flow through pipes can roughly be divided into two: Laminar flow - see Hagen-Poiseuille flow Turbulent flow - see Moody diagram ... Pipe flow does not have a free surface which is found in open-channel flow. Pipe flow, being confined within closed conduit, ... In fluid mechanics, pipe flow is a type of liquid flow within a closed conduit, such as a pipe or tube. The other type of flow ...
https://en.wikipedia.org/wiki/Pipe_flow
FluidicsFluidics
"Early turbulence and pulsatile flows enhance diodicity of Tesla's macrofluidic valve". Nature Communications. 12 (12): 2884. ... It's a leaky diode, i.e. the reverse flow is non-zero for any applied pressure difference. Tesla valve also has non-linear ... In thrust vectoring, in jet engine nozzles, swiveling parts are replaced by slots which inject fluid flows into jets. Such ... Scanned article available online from Google Books: Popular Science June 1967 Visualization of the flow field of a fluidic ...
https://en.wikipedia.org/wiki/Fluidics
ChorioangiomaChorioangioma
Doppler examination shows anechoic cystic areas, with pulsatile flow in spectral analysis. Some chorioangiomas may be solid ... When chorioangiomas have deceased blood flow, fetal hemodynamics and clinical outcome are found to be improved. It is the most ... Large chorioangiomas with decreased echogenicity, decreased tumor volume and decreased blood flow in colour doppler images are ...
https://en.wikipedia.org/wiki/Chorioangioma
Impedance pumpImpedance pump
Rinderknecht, Derek Gresham (2008). "Development of a microimpedance pump for pulsatile flow transport : Part 1: Flow ... Tapping the end of a tube will cause flow of liquid inside the system. Very small versions of an impedance pump -- a micro ... Part 2: A systematic study of steady and pulsatile transport in microscale cavities.". Dissertation (Ph.D.), California ...
https://en.wikipedia.org/wiki/Impedance_pump
Axel Radlach PriesAxel Radlach Pries
Pulsatile shear and Gja5 modulate arterial identity and remodeling events during flow-driven arteriogenesis. Buschmann I*, ... Resistance to blood flow in microvessels in vivo. Pries AR, Secomb TW, Gessner T, Sperandio MB, Gross JF, Gaehtgens P. Circ Res ... Blood flow in microvascular networks. Pries AR and Secomb TW. In: Handbook of Physiology: Microcirculation, edited by Tuma RF, ...
https://en.wikipedia.org/wiki/Axel_Radlach_Pries
Aortic aneurysmAortic aneurysm
Before rupture, an AAA may present as a large, pulsatile mass above the umbilicus. A bruit may be heard from the turbulent flow ...
https://en.wikipedia.org/wiki/Aortic_aneurysm
Earl WoodEarl Wood
After his work on the G-Suit, Wood worked on techniques for measuring cardiac blood flow. He was granted a patent for the ear ... The water-filled, pulsatile pressure suits were developed to effect venous return. However, Wood and colleagues' detailed ... Grace, JB; Fox, IJ; Crowley, WP Jr; Wood, EH (November 1957). "Thoracic-aorta flow in man". J Appl Physiol. 11 (3): 405-418. ... Smith, HC; Sturm, RE; Wood, EH (August 1973). "Videodensitometric system for measurement of vessel blood flow, particularly in ...
https://en.wikipedia.org/wiki/Earl_Wood
Atrium (heart)Atrium (heart)
But without functioning atria, venous flow becomes pulsatile, and the overall circulation rate decreases significantly. Atria ... to be able to accept venous flow without interruption. By preventing the inertia of interrupted venous flow that would ... In an adult, an atrial septal defect results in the flow of blood in the reverse direction - from the left atrium to the right ... At birth, when the first breath is taken fetal blood flow is reversed to travel through the lungs. The foramen ovale is no ...
https://en.wikipedia.org/wiki/Atrium_(heart)
Womersley numberWomersley number
It is a dimensionless expression of the pulsatile flow frequency in relation to viscous effects. It is named after John R. ... In a flow distribution network that progresses from a large tube to many small tubes (e.g. a blood vessel network), the ... The Womersley number of human blood flow can be estimated as follows: α = L ( ω ρ μ ) 1 2 . {\displaystyle \alpha =L\left({\ ... In these regions the inertia force becomes less important and the flow is determined by the balance of viscous stresses and the ...
https://en.wikipedia.org/wiki/Womersley_number
Norwood procedureNorwood procedure
Direct canalization to the right ventricle provides pulsatile blood flow compared to the Blalock-Taussig conduit. The Single ... In both cases a conduit is used to direct blood flow into the lungs, however anatomic anchoring varies. There are two different ... To accomplish this, blood flow to the lungs is disrupted, and therefore an alternative path must be created to provide blood ... Second step of the procedure establishes blood flow to the lungs. Variations to this step have been proposed over the years, ...
https://en.wikipedia.org/wiki/Norwood_procedure
Cerebrospinal fluid flow MRICerebrospinal fluid flow MRI
Cerebrospinal fluid (CSF) flow MRI is used to assess pulsatile CSF flow both qualitatively and quantitatively. Time-resolved 2D ... CSF Fluid Flow MRI detects back and forth flow of Cerebrospinal fluid that corresponds to vascular pulsations from mostly the ... However, overestimating the VENC value leads to a lower acquired flow signal and a lower SNR. Typical CSF flow is 5-8 cm/s; ... The study of CSF flow became one of Phase-contrast MRI's major applications. The key to Phase-contrast MRI (PC-MRI) is the use ...
https://en.wikipedia.org/wiki/Cerebrospinal_fluid_flow_MRI
Cardiac outputCardiac output
Bernstein, Donald P (2010). "Impedance cardiography: Pulsatile blood flow and the biophysical and electrodynamic basis for the ... This flow data can be used in a flow-versus-time graph. The area under the flow-versus-time curve for one cardiac cycle is the ... Cardiac output is a global blood flow parameter of interest in hemodynamics, the study of the flow of blood. The factors ... which is then multiplied by the VTI of the Doppler flow profile across the aortic valve to determine the flow volume per beat ( ...
https://en.wikipedia.org/wiki/Cardiac_output
Diabetic foot ulcerDiabetic foot ulcer
Endothelial cell specific nitric oxide synthase (EcNOS) is activated by the pulsatile flow of blood through vessels. Nitric ... Continuous diffusion of oxygen (CDO) - CDO delivers continuous oxygen to an occluded, moist wound site at much lower flow rates ... and arms due to distal nerve damage and low blood flow. Autonomic neuropathy causes Sudomotor dysfunction and dryness of the ... oxide produced by EcNOS, maintains the diameter of blood vessels and proper blood flow to tissues. In addition to this, nitric ...
https://en.wikipedia.org/wiki/Diabetic_foot_ulcer
Inferior tympanic arteryInferior tympanic artery
This can result in pulsatile tinnitus. The resulting Aberrant Carotid artery can mimic neoplasm on CT. This article ... the Inferior tympanic artery can provide collateral ICA circulation by reversing flow of the caroticotympanic artery ( ...
https://en.wikipedia.org/wiki/Inferior_tympanic_artery
In vitro models for calcificationIn vitro models for calcification
Lim, W. L.; Chew, Y. T.; Chew, T. C.; Low, H. T. (2001-11-01). "Pulsatile flow studies of a porcine bioprosthetic aortic valve ... These models can combine the constant supersaturation principle together with pulsatile flow, which is characteristic of the ... This model does not provide the flow or the mechanical stimuli to the tissue. Both flow and mechanical stimuli affect the ... Dynamic models can vary in terms of the means of providing the flow in the system, as well as in terms of the dynamic ...
https://en.wikipedia.org/wiki/In_vitro_models_for_calcification
Melissa SkalaMelissa Skala
Skala has developed organ-on-a-chip devices to study pulsatile flow and how it impacts cardiovascular disease. She is ... Mohns, Mariel (2020-11-16). "Measuring blood flow with a beating "heart-on-a-chip"". Morgridge Institute for Research. ...
https://en.wikipedia.org/wiki/Melissa_Skala
Aortic valve area calculationAortic valve area calculation
Agarwal, R. K.; Okpara, E (2010). "Numerical Study of Pulsatile Flow through Models of Vascular and Aortic Valve Stenoses and ... In practical terms, the flow from the left ventricular outflow tract (LVOT) is compared to the flow at the level of the aortic ... The continuity equation states that the flow in one area must equal the flow in a second area if there are no shunts between ... The flow through the LVOT, or LV stroke volume (in cm3), can be calculated by measuring the LVOT diameter (in cm), squaring ...
https://en.wikipedia.org/wiki/Aortic_valve_area_calculation
Dinker Belle RaiDinker Belle Rai
He discovered that venous blood flow is pulsatile which, prior to Rai's discovery, was described only as linear flow. He is ...
https://en.wikipedia.org/wiki/Dinker_Belle_Rai
O. H. FrazierO. H. Frazier
... the pulsatile HeartMate I in 1986, and the replacement of a diseased heart with a continuous flow device using two HeartMate II ... His most significant achievements have been in the development of the non-pulsatile implantable LVADs, the Jarvik, HeartMate II ... Throughout the 1970s and 1980s, he continued experimental work toward the development of the implantable long-term pulsatile ... also a continuous flow pump. By the end of 2013, Frazier and his THI team had implanted their 1,000th LVAD, more than fifty ...
https://en.wikipedia.org/wiki/O._H._Frazier
PheochromocytomaPheochromocytoma
The normal blood vessel is open, allowing for adequate blood flow. When catecholamines activate the alpha receptor, the vessel ... and can result in pulsatile tinnitus (ringing of the ear), hearing loss, aural fullness, dyspnea (difficulty breathing), and ... Norepinephrine (a catecholamine) is hypothesized to result in damaged cardiac tissue by inhibiting coronary blood flow and ... Norepinephrine causes vessels to narrow, thereby limiting blood flow and inducing ischemia. Multiple organ dysfunction syndrome ...
https://en.wikipedia.org/wiki/Pheochromocytoma
Cold-stimulus headacheCold-stimulus headache
Another theory into the cause of cold-stimulus headaches is explained by increased blood flow to the brain through the anterior ... and pulsatile (throbbing pain) phases of migraines. It is possible to have a cold-stimulus headache in both hot and cold ... so the blood flow could raise the pressure inside the skull and induce pain that way. As the intracranial pressure and ...
https://en.wikipedia.org/wiki/Cold-stimulus_headache
Biofluid dynamicsBiofluid dynamics
As velocity increases, flow can become disorganized and chaotic. This is known as turbulent flow. Laminar flow occurs in flow ... The heart can be thought of as a muscular pump, consisting of four chambers, and pulsatile muscles which pump and circulates ... Internal flows such as cardiovascular blood flow and respiratory airflow, and external flows such as flying and aquatic ... Most blood flow in humans is laminar, having a Re of 300 or less, it is possible for turbulence to occur at very high flow ...
https://en.wikipedia.org/wiki/Biofluid_dynamics
Vascular remodelling in the embryoVascular remodelling in the embryo
... however after three days the flow becomes pulsatile. Pulsatile flow plays an important role in vascular remodelling, as flow ... April, 2010). Pulsatile shear and Gja5 modulate arterial identity and remodelling events during flow-driven arteriogenesis. ... The shear stress applied to vessel walls is proportional to the viscosity and flow patterns of the fluid. Disturbed flow ... blood vessels in the developing embryo are much more resistant to flow. This means that increases in flow or pressure can only ...
https://en.wikipedia.org/wiki/Vascular_remodelling_in_the_embryo
ImpellaImpella
... the circulatory system transitions from a pulsatile mechanism to continuous flow. Cellular response to cardiogenic shock is ... Meyns, B; Stolinski, J; Leunens, V; Verbeken, E; Flameng, W (2003). "Left ventricular support by catheter-mounted axial flow ... Lastly, augmented cardiac output and forward flow from the left ventricle decreases pulmonary capillary wedge pressure and ... poorly described by either method (counterpulsation or continuous flow). Control of directional flow of the device (magnetic ...
https://en.wikipedia.org/wiki/Impella
Follicle-stimulating hormoneFollicle-stimulating hormone
... day one is the first day of menstrual flow). The cohort of small antral follicles is normally sufficient in number to produce ... factor produced by small follicles during the first half of the follicle phase also exerts a negative feedback on pulsatile ...
https://en.wikipedia.org/wiki/Follicle-stimulating_hormone
Artificial heart valveArtificial heart valve
... which can impede the flow of blood through the valve (stenosis) and/or let blood flow backwards through the valve ( ... "Assessment of a novel stentless mitral valve using a pulsatile mitral valve simulator". The Journal of Heart Valve Disease. 21 ... The metal ring holds, by means of two metal supports, a disc that opens when the heart beats to let blood flow through, then ... Their main purpose is to keep blood flowing in the proper direction through the heart, and from the heart into the major blood ...
https://en.wikipedia.org/wiki/Artificial_heart_valve
Artificial heartArtificial heart
... provide continuous flow. These pumps (which may be centrifugal or axial flow) are smaller and potentially more durable and last ... Imachi K, Chinzei T, Abe Y, Mabuchi K, Imanishi K, Yonezawa T, Kouno A, Ono T, Atsumi K, Isoyama T (1991). "A new pulsatile ... Several continuous-flow ventricular assist devices have been approved for use in the European Union, and, as of August 2007, ... A centrifugal pump or an axial-flow pump can be used as an artificial heart, resulting in the patient being alive without a ...
https://en.wikipedia.org/wiki/Artificial_heart
ArterioleArteriole
Blood pressure in the arteries supplying the body is a result of the work needed to pump the cardiac output (the flow of blood ... The up and down fluctuation of the arterial blood pressure is due to the pulsatile nature of the cardiac output and determined ... The greatest change in blood pressure and velocity of blood flow occurs at the transition of arterioles to capillaries.This ... The decreased velocity of flow in the capillaries increases the blood pressure, due to Bernoulli's principle. This induces gas ...
https://en.wikipedia.org/wiki/Arteriole
Dural arteriovenous fistulaDural arteriovenous fistula
Pulsatile tinnitus Occipital bruit Headache Visual impairment Papilledema Pulsatile tinnitus is the most common symptom in ... The flow within the draining vein or venous sinus is anterograde. Type Ia - simple dural arteriovenous fistulas have a single ... Carotid-cavernous DAVFs, on the other hand, are more closely associated with pulsatile exophthalmos. DAVFs may also be ... The high pressure within a Type II dural AV fistula causes blood to flow in a retrograde fashion into subarachnoid veins which ...
https://en.wikipedia.org/wiki/Dural_arteriovenous_fistula
Venous humVenous hum
It may be loud enough to result in audible pulsatile tinnitus. It is by far the most common type of normal continuous murmur, ... Venous hum is a benign auscultatory phenomenon caused by the normal flow of blood through the jugular veins. At rest, 20% of ... Though the exact mechanism is still unclear, it has been suggested that the hum occurs when otherwise silent laminar flow ... Abnormal and potentially serious conditions such as thyrotoxicosis and anemia, by augmenting blood flow through the jugular ...
https://en.wikipedia.org/wiki/Venous_hum
DiastoleDiastole
... and hemodialysis that replace pulsatile flow with continuous blood flow. Examining diastolic function during a cardiac stress ... The ventricular filling flow (or flow from the atria into the ventricles) has an early (E) diastolic component caused by ... The atrial kick does not supply the larger amount of flow (during the cardiac cycle) as about 80 percent of the collected blood ... The open mitral valve allows blood in the atrium (accumulated during atrial diastole) to flow into the ventricle (see graphic ...
https://en.wikipedia.org/wiki/Diastole
NASA spinoff technologiesNASA spinoff technologies
The pump is approximately one-tenth the size of other currently marketed pulsatile VADs. Because of the pump's small size, ... Langley Research Center's wind tunnel testing facilities and fluid flow analysis software supported Speedo's design of a space ...
https://en.wikipedia.org/wiki/NASA_spinoff_technologies
Cerebrospinal fluidCerebrospinal fluid
Fluid movement is pulsatile, matching the pressure waves generated in blood vessels by the beating of the heart. Some authors ... The pathway and extent are currently not known, but may involve CSF flow along some cranial nerves and be more prominent in the ... This continuous flow into the venous system dilutes the concentration of larger, lipid-insoluble molecules penetrating the ... CSF also serves a vital function in the cerebral autoregulation of cerebral blood flow. CSF occupies the subarachnoid space ( ...
https://en.wikipedia.org/wiki/Cerebrospinal_fluid
Gunshot woundGunshot wound
Hard signs include active bleeding, expanding or pulsatile hematoma, bruit/thrill, absent distal pulses and signs of extremity ... Those with signs of a tension pneumothorax (asymmetric breathing, unstable blood flow, respiratory distress) should immediately ...
https://en.wikipedia.org/wiki/Gunshot_wound
List of MeSH codes (H01)List of MeSH codes (H01)
... pulsatile flow MeSH H01.671.868 - temperature MeSH H01.671.868.272 - cold MeSH H01.671.868.272.437 - freezing MeSH H01.671. ...
https://en.wikipedia.org/wiki/List_of_MeSH_codes_(H01)
Vascular resistanceVascular resistance
Measurement of real pulsatile blood flow using X-ray PIV technique with CO2 microbubbles, Hanwook Park, Eunseop Yeom, Seung-Jun ... According to very recent results showing the sheath flow surrounding the plug flow in a vessel, the sheath flow size is not ... will result in an increased flow to tissues and an increased venous flow back to the heart. An increased SVR will decrease flow ... Thurston assembled this layer to the flow resistance to describe blood flow by means of a viscosity η(δ) and thickness δ from ...
https://en.wikipedia.org/wiki/Vascular_resistance
Heart soundsHeart sounds
Heart murmurs are generated by turbulent flow of blood and a murmur to be heard as turbulent flow must require pressure ... a metre in poetry that follows a similar rhythm to the human heartbeat Pulsatile tinnitus - hearing a heartbeat sound in one or ... Aortic blood flow quickly reverses back toward the left ventricle, catching the pocket-like cusps of the aortic valve, and is ... The term murmur only refers to a sound believed to originate within blood flow through or near the heart; rapid blood velocity ...
https://en.wikipedia.org/wiki/Heart_sounds
History of continuous noninvasive arterial pressureHistory of continuous noninvasive arterial pressure
... pulsatile, calibrated blood pressure measurement from a finger. J Clin Monit, 1, 17-27 (1985). Wesseling KH, Settels JJ, De Wit ... volume and flow in the finger. Digest of the 10th international conference on medical and biological engineering - Dresden ( ...
https://en.wikipedia.org/wiki/History_of_continuous_noninvasive_arterial_pressure
ThyroidThyroid
TSH release in turn is stimulated by thyrotropin releasing hormone (TRH), released in a pulsatile manner from the hypothalamus ... Combined, these factors increase blood flow and the body's temperature. Developmental. Thyroid hormones are important for ...
https://en.wikipedia.org/wiki/Thyroid
OptogeneticsOptogenetics
January 2014). "Flow of cortical activity underlying a tactile decision in mice". Neuron. 81 (1): 179-194. doi:10.1016/j.neuron ... In addition, a rapid negative feedback loop in the RAF-MEK-ERK pathway was discovered using pulsatile activation of a ... and Büldt in 1994 had already shown functional heterologous expression of a bacteriorhodopsin for light-activated ion flow in ...
https://en.wikipedia.org/wiki/Optogenetics
CollateralizationCollateralization
This is initiated by deformation of the endothelial cells through increased pulsatile fluid shear stress (FSS) caused by the ... Freedman SB, et al., "Influence of coronary collateral blood flow on the development of exertional ischemia and Q wave ... of coronary blood flow to an otherwise-occluded blood vessel, and, while not capable of preventing ischemia in the event of ... great cardiac vein flow that was significantly greater in those with collaterals than in those without them. Spasm resulted in ...
https://en.wikipedia.org/wiki/Collateralization
pulsatile flow - CFD Online Discussion Forums - Threads Tagged with pulsatile flowpulsatile flow - CFD Online Discussion Forums - Threads Tagged with pulsatile flow
APS -70th Annual Meeting of the APS Division of Fluid Dynamics - Event - Pulsatile flow-induced shear stress in large vessels...APS -70th Annual Meeting of the APS Division of Fluid Dynamics - Event - Pulsatile flow-induced shear stress in large vessels...
Abstract: A5.00008 : Pulsatile flow-induced shear stress in large vessels affects VE-Cadherin and Neuregulin-1 expression in ... It is well known that endothelial cell behavior is modulated by flow-induced shear stress. In smaller vessels, where Reynolds ... shear stress is pulsatile. We investigated the effect of realistic healthy and unhealthy large vessel shear stresses on the ... Western blots were performed to quantify the amount of VE-Cad and NRG-1 expressed by HUVECs after exposure to flow-induced ...
https://meetings.aps.org/Meeting/DFD17/Session/A5.8
Pulsatile blood flow effects on temperature distribution and heat transfer in rigid vessels. | Scholars@DukePulsatile blood flow effects on temperature distribution and heat transfer in rigid vessels. | [email protected]
Pulsatile blood flow effects on temperature distribution and heat transfer in rigid vessels. ... Pulsatile blood flow effects on temperature distribution and heat transfer in rigid vessels. Journal Article (Journal Article) ... A simple model of a straight rigid blood vessel with unsteady periodic flow is considered. A numerical solution that considers ... The results show that: the pulsating axial velocity produces a pulsating temperature distribution; reversal of flow occurs in ...
https://scholars.duke.edu/display/pub665637
Pulsatile flowPulsatile flow
... a pulsatile flow phantom study Passive paramagnetic markers on magnetic resonance imaging (MRI)-compatible endovascular devices ...
https://www.nano4imaging.com/tag/pulsatile-flow/
Pulsatile flow; Flow, Pulsating; Perfusion, PulsatilePulsatile flow; Flow, Pulsating; Perfusion, Pulsatile
Flow, Pulsating; Perfusion, Pulsatile. On-line free medical diagnosis assistant. Ranked list of possible diseases from either ... Pulsatile flow (Flow, Pulsating; Perfusion, Pulsatile). Rhythmic, intermittent propagation of a fluid through a blood VESSEL or ... piping system, in contrast to constant, smooth propagation, which produces laminar flow. ...
https://lookfordiagnosis.com/mesh_info.php?term=pulsatile%20flow&lang=1
PULSATILE VENOUS FLOW IN LEGS, Perforated veins
Sclerotherapy supposes the use of a sclerosing agent, which scars the inflamed tissue, thus reducing the blood flow towards the ...
http://realkafka.ro/3512-perforated-veins.php
IMSEAR at SEARO: Comparative study of pulsatile and nonpulsatile flow during cardio-pulmonary bypass.
Pulsatile CPB is considered to be more physiological than nonpulsatile flow as the pulsatile energy ensures the patency of the ... Comparative study of pulsatile and nonpulsatile flow during cardio-pulmonary bypass.. Authors: Poswal, Pardeep. Mehta, Yatin. ... The purpose of this study was to compare the effect of pulsatile and nonpulsatile flow on the coagulation profile, liver and ... Poswal P, Mehta Y, Juneja R, Khanna S, Meharwal ZS, Trehan N. Comparative study of pulsatile and nonpulsatile flow during ...
https://imsear.searo.who.int/handle/123456789/1474
Assessment of turbulent viscous stress using ICOSA 4D Flow MRI for prediction of hemodynamic blood damage | Scientific ReportsAssessment of turbulent viscous stress using ICOSA 4D Flow MRI for prediction of hemodynamic blood damage | Scientific Reports
... in stenotic turbulent blood flow. The results showed that 4D Flow MRI underestimates the maximum principal shear stress of ... In conclusion, this study demonstrated the feasibility of 4D Flow MRI based quantification of TVSS and BDI which are closely ... This study evaluated the novel application of turbulence tensor measurements using simulated 4D Flow MRI data with six- ... which are dominated by shear stresses in highly fluctuating turbulent flow, has not been feasible. ...
https://www.nature.com/articles/srep39773/?error=cookies_not_supported&code=6034897e-516b-43a2-b4b9-c85a774acaa0
MoviesMovies
Pulsatile flow in curved tube Results of Laser-Doppler-Anemometry of pulsatile flow in a curved tube of a Newtonian (left) and ... Flow past a confined excentric cylinder and in our cross-slot device Flow past a confined cylinder and in our real 2D cross- ... Foam drop in shear flow (4 drops) Foam drop containing 4 equal-sized inner drops at volume fraction 95% in simple shear flow (u ... Drop deformation and breakup in shear flow (u=y) at Ca=0.45 and viscosity ratio 1. After the initial deformation the flow stops ...
https://www.tue.nl/en/research/research-institutes/top-research-groups/materials-technology/research/group-publications/movies/
Pulsatile Flow Promotes Adhesion in Sickle Cell Disease: Clinical Application of a Microfluidic Bioassay.Pulsatile Flow Promotes Adhesion in Sickle Cell Disease: Clinical Application of a Microfluidic Bioassay.
Pulsatile and non-pulsatile flow conditions. Flow adhesion assays were performed under non-pulsatile (0 Hz) and pulsatile flow ... Pulsatile Flow Promotes Adhesion in Sickle Cell Disease: Clinical Application of a Microfluidic Bioassay.. Pulsatile Flow ... Despite pulsatile flow adaptability most microfluidic flow adhesion assays use flow delivery systems that drive continuous ... Adhesion was significantly increased in the context of pulsatile blood flow compared to non-pulsatile blood flow (Fig. 3A, ...
https://www.functionalfluidics.com/publications/pulsatile-flow-promotes-adhesion-in-sickle-cell-disease-clinical-application-of-a-microfluidic-bioassay
Non-Newtonian pulsatile flow through an artery with two stenosis<...
Non-Newtonian pulsatile flow through an artery with two stenosis. Gaurav Kumar*, Hitesh Kumar, Kabir Mandia, M. Zunaid, N. A. ... Non-Newtonian pulsatile flow through an artery with two stenosis. In: Materials Today: Proceedings. 2021 ; Vol. 46. pp. 10793- ... title = "Non-Newtonian pulsatile flow through an artery with two stenosis",. abstract = "The purpose of this work is to ... Non-Newtonian pulsatile flow through an artery with two stenosis. / Kumar, Gaurav; Kumar, Hitesh; Mandia, Kabir et al. ...
https://squ.pure.elsevier.com/en/publications/non-newtonian-pulsatile-flow-through-an-artery-with-two-stenosis
Cécile.Daversin-Catty | Simula Research LaboratoryCécile.Daversin-Catty | Simula Research Laboratory
Geometrically reduced modelling of pulsatile flow in perivascular networks. Frontiers in Physics 10 (2022). ...
https://www.simula.no/people/cecile?f%5Bauthor%5D=9615
Aortic Dissection: Practice Essentials, Background, AnatomyAortic Dissection: Practice Essentials, Background, Anatomy
Hypertension or pulsatile blood flow can propagate the dissection.. Pregnancy can be a risk factor for aortic dissection, ... Typically, flow in the false lumen is slower than in the true lumen, and the false lumen often becomes aneurysmal when ... The volume of blood ejected into the aorta, the compliance of the aorta, and resistance to blood flow are responsible for the ... The aortic wall is exposed to high pulsatile pressure and shear stress (the steep slope of the pressure curve; ie, the water ...
https://www.medscape.com/answers/2062452-68511/what-is-the-role-of-the-aorta
A Fluid-Structure Interaction Finite Element Analysis of Pulsatile Blood Flow Through a Compliant Stenotic Artery | J. Biomech...A Fluid-Structure Interaction Finite Element Analysis of Pulsatile Blood Flow Through a Compliant Stenotic Artery | J. Biomech...
A Fluid-Structure Interaction Finite Element Analysis of Pulsatile Blood Flow Through a Compliant Stenotic Artery M. Bathe, M. ... Blood flow, Finite element analysis, Fluid structure interaction, Flow (Dynamics), Fluids, Pressure drop, Stress, Compressive ... A new model is used to analyze the fully coupled problem of pulsatile blood flow through a compliant, axisymmetric stenotic ... Bathe, M., and Kamm, R. D. (August 1, 1999). "A Fluid-Structure Interaction Finite Element Analysis of Pulsatile Blood Flow ...
https://offshoremechanics.asmedigitalcollection.asme.org/biomechanical/article-abstract/121/4/361/398083/A-Fluid-Structure-Interaction-Finite-Element?searchresult=1
Pulsatile shear and Gja5 modulate arterial identity and remodeling events during flow-driven arteriogenesis | FOLIA - Fribourg...Pulsatile shear and Gja5 modulate arterial identity and remodeling events during flow-driven arteriogenesis | FOLIA - Fribourg...
Blood flow Pulsatile shear Chick Mouse English In the developing chicken embryo yolk sac vasculature, the expression of ... Pulsatile shear and Gja5 modulate arterial identity and remodeling events during flow-driven arteriogenesis. * Buschmann, Ivo ... The expression of Gja5 correlated with arterial flow patterns: the redistribution of arterial flow provoked by vitelline artery ... We conclude that pulsatile shear patterns may be central for supporting arterial identity, and that arterial Gja5 expression ...
https://folia.unifr.ch/unifr/documents/301757
Choroid Plexus Papilloma Imaging: Practice Essentials, Pathophysiology, EpidemiologyChoroid Plexus Papilloma Imaging: Practice Essentials, Pathophysiology, Epidemiology
Doppler ultrasonographic studies have shown pulsatile intratumoral vascular channels with biphasic flow. Occasionally, ... Flow voids are seen, indicating active blood flow. Lesions are brilliantly enhancing because of rich vascularity. Use of ... This lesion continues to demonstrate bidirectional flow throughout the diastole, indicating blood flow through vessels arranged ... Clinical symptoms are predominantly due to hydrocephalus, which results from direct mechanical obstruction to the flow of ...
http://emedicine.medscape.com/article/339299-overview
David N. Loy, MD | Neuroradiology | UVADavid N. Loy, MD | Neuroradiology | UVA
... pulsatile tinnitus; endovascular flow-diversion; brain and spinal cord arteriovenous malformations (AVM); dural AV fistula; ...
https://uvahealth.com/findadoctor/profile/david-n-loy
Tinnitus treatment. Relief from ringing in the ears | PhonakTinnitus treatment. Relief from ringing in the ears | Phonak
Your circulatory system (blood flow) and somatic movements (musculo-skeletal) produce the sounds. It is very rare; less than 1 ...
https://www.phonak.com/us/en/phonak-landing-pages/hearing-loss/tinnitus.html
General Engineering & Skills - Oxford University PressGeneral Engineering & Skills - Oxford University Press
Examples include flow through blood vessels, pulsatile flow, and pattern formation. The book includes popular vignettes and ... This is a readable and attractively presented overview of fluid flow in biological systems. ...
https://global.oup.com/ukhe/disciplines/engineering/general-engineering-and-skills/?cc=gb&lang=en?cc&facet_narrowbyprice_facet=over50&cc=gb&lang=en?cc
MAUDE Adverse Event Report: MEDTRONIC NEUROSURGERY UNKNOWN CATHETER SHUNT, CENTRAL NERVOUS SYSTEM AND COMPONENTS
An infusion study performed revealed that the baseline pressure was low and non-pulsatile. After the start of infusion, icp ... Icp stabilised at 10 mm hg showing low resistance to distal flow. These results indicated intermittent blockage of the ... a manoeuvre which blocks distal flow. After the use of this technique, both patients¿ symptoms improved and they have remained ... s lactate solution was injected into the shunt prechamber of the patient while distal flow was blocked by temporary compression ...
https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=8183284&pc=JXG
McNamee P - Search Results - PubMedMcNamee P - Search Results - PubMed
Analysis of spin-echo rephasing with pulsatile flow in 2D FT magnetic resonance imaging. Katz J, Peshock RM, McNamee P, ...
https://pubmed.ncbi.nlm.nih.gov/?term=McNamee+P&cauthor_id=2768713
Find Research outputs - the University of Bath's research portal
PULSATILE FLOW IN VADS: CFD ANALYSIS OF VELOCITY FIELDS AROUND THE PRESSURE-FLOW LOOP. Fraser, K. & Khoo, D. P. Y., 12 Sep 2018 ... Pulsatile Flow in Ventricular Assist Devices: CFD Analysis of Velocity Fields around the Pressure-Flow Loop. Fraser, K. & Khoo ...
https://researchportal.bath.ac.uk/en/publications/?ordering=publicationYearThenTitle&descending=true&showAdvanced=false&allConcepts=true&inferConcepts=false&originalSearch=&improvedLayoutOrganisationUuid=&format=&page=327
Frontiers | Transit Time Measurement in Indicator Dilution Curves: Overcoming the Missing Ground Truth and Quantifying the ErrorFrontiers | Transit Time Measurement in Indicator Dilution Curves: Overcoming the Missing Ground Truth and Quantifying the Error
Previous approaches show that the measured flow has a significant deviation compared to the gold standard reference (ultrasonic ... Previous approaches show that the measured flow has a 8 significant deviation compared to the gold standard reference ( ... ultrasonic flow meter). In order 9 to systematically address the possible sources of error, we investigated the error in ... we first computed many diverse indicator dilution curves using an in silico simulation of the indicators flow. Second, we post ...
https://www.frontiersin.org/articles/10.3389/fphys.2021.588120/full
Anders EklundAnders Eklund
Can pulsatile CSF flow across the cerebral aqueduct cause ventriculomegaly?: A prospective study of patients with communicating ... 4D flow MRI: automatic assessment of blood flow in cerebral arteries Biomedical Engineering & Physics Express, Institute of ... Accuracy of blood flow assessment in cerebral arteries with 4D flow MRI: Evaluation with three segmentation methods ... Assessing cerebral arterial pulse wave velocity using 4D flow MRI Journal of Cerebral Blood Flow and Metabolism, Sage ...
https://www.umu.se/personal/anders-eklund/
francis-99-as-a-reference-study - NTNU
Small amplitude pulsatile flow in hydraulic transmission lines. 8247102935. Stuksrud, DB. 1998. System dynamics in hydropower ... Secondary flow fields in Francis turbines: mapping and analyzing dynamics in rotor-stator interaction and draft tube flow with ... Analysis of non-stationary flow in turbine runners. 8271197460. Berntsen, G. 2003. Numerical analysis of the two-phase Pelton ... Unsteady flow in wicket gate and runner with focus on static and dynamic load on runner. 9788247134085. ...
https://www.ntnu.edu/nvks/literature-publications/postdocs-and-phd
NIOSHTIC-2 Search Results - Full View
Flow measurements were made for inspiratory flow and pulsatile inspiratory flow. Pulsatile inspiratory flow was found to be ... steady inspiratory flow and pulsatile inspiratory flow. The differences and similarities between deposition patterns in the ... more realistic than steady flow in this model. The hollow airway cast system was evaluated for use in investigations of ...
http://www2a.cdc.gov/nioshtic-2/BuildQyr.asp?s1=aerosol+or+aerosols&f1=TI&s2=&PageNo=259&RecNo=2589&View=f&
Radiological Imaging of Nail Disorders (PART II) - Radiologi... : Indian Dermatology Online JournalRadiological Imaging of Nail Disorders (PART II) - Radiologi... : Indian Dermatology Online Journal
USD may show low resistance and pulsatile flow within the lesion. MRI shows a lesion that is hypointense on T1-weighted and ... A specific finding is hypervascular appearance on USD, due to a high-velocity flow in intramural shunt vessels.[21] CT imaging ... Activity of psoriatic onychopathy also correlates with USG-based blood flow evaluation. Regardless of coexistent nail changes, ... myxoid cyst is seen as a round or oval shaped anechoic structure with posterior acoustic reinforcement and absence of flow. MRI ...
https://journals.lww.com/idoj/Fulltext/2022/13060/Radiological_Imaging_of_Nail_Disorders__PART_II___.2.aspx
reddit tinnitus cure tinnitus ireland cure | pulsatile tinnitus cure uk tinnitus cure in 10 minutes
This kind of tinnitus is most often caused by problems with blood flow in the head or neck. Pulsatile tinnitus also may be ... Pulsatile tinnitus is a rare type of tinnitus that sounds like a rhythmic pulsing in the ear, usually in time with your ... An ultrasound can reveal how blood flows within vessels, but is only useful for accessible vessels. It is not helpful for blood ... People without warning signs in whom tinnitus recently developed should call their doctor, as should people with pulsatile ...
https://banishtinnitus.net/hissing-tinnitus-cure-tinnitus-cure-ginkgo-biloba.html
Pulsatile TinnitusPulsatile Tinnitus
... is usually from blood vessels close to your ear ... Anything that increases blood flow or turbulence such as hyperthyroidism, low blood viscosity (e.g. anemia), or tortuous blood ... Testing for pulsatile tinnitus:. It is common for persons with pulsatile tinnitus to have some sort of procedure done in the ... In pulsatile tinnitus, people hear something resembling their heartbeat in their ear.. *Pulsatile tinnitus is usually due to a ...
https://dizziness-and-balance.com/disorders/hearing/tinnitus/pulsatile.html
TinnitusPerfusionArterialVenousBloodCerebrospinal fluidArteryVitroIntermittentTime-averagedEndovascularVesselsBoundary conditionsWaveformVersusEndothelialVelocityIncompressibleContinuous flowLaminarVascularShear stressVADsObstructionMetricsOcclusionMeasurements were madeVivoAssessmentPumpComparativeMagneticArteriesQuantificationSteady flowParametersComplexUrinePatients20222016PatternsHemodynamicsPressureVesselFluid flowVentricularClinicalStudyBiological
Tinnitus17
  • This is known as pulsatile tinnitus). (phonak.com)
  • People without warning signs in whom tinnitus recently developed should call their doctor, as should people with pulsatile tinnitus. (banishtinnitus.net)
  • In pulsatile tinnitus, people hear something resembling their heartbeat in their ear. (dizziness-and-balance.com)
  • Pulsatile tinnitus is usually due to a small blood vessel that is coupled by fluid to your ear drum. (dizziness-and-balance.com)
  • Rarely pulsatile tinnitus can be caused by more serious problems -- aneurysms, increased pressure in the head ( hydrocephalus ), and hardening of the arteries. (dizziness-and-balance.com)
  • Inner ear disorders that increase hearing sensitivity ( such as SCD ) can cause pulsatile tinnitus. (dizziness-and-balance.com)
  • As this condition can be corrected surgically, it is one of the few 'fixable' causes of pulsatile tinnitus. (dizziness-and-balance.com)
  • An enlarged jugular bulb on the involved side is common in persons with venous type pulsatile tinnitus. (dizziness-and-balance.com)
  • Anything that increases blood flow or turbulence such as hyperthyroidism, low blood viscosity (e.g. anemia), or tortuous blood vessels may cause pulsatile tinnitus. (dizziness-and-balance.com)
  • It is common for persons with pulsatile tinnitus to have some sort of procedure done in the Radiology department, looking for something that can be fixed. (dizziness-and-balance.com)
  • Other entities than the ones listed above that can sometimes be seen on radiological testing and that can cause pulsatile tinnitus, include AVM's, aneurysms, carotid artery dissection, fibromuscular dysplasia, venous hums from the jugular vein (found in half the normal population), vascular tumors such as glomus, ossifying hemangiomas of the facial nerve, osseous dysplasias such as otosclerosis and Paget's, and elevated intracranial pressure. (dizziness-and-balance.com)
  • Practically, MRI/MRA or CT is often suggested in younger patients with unilateral pulsatile tinnitus. (dizziness-and-balance.com)
  • In older patients, pulsatile tinnitus is often due to atherosclerotic disease and it is less important to get an MRI/MRA. (dizziness-and-balance.com)
  • Some people hear their heartbeat inside the ear - a phenomenon called pulsatile tinnitus. (harvard.edu)
  • Pulsatile tinnitus may be more noticeable at night, when you're lying in bed and there are fewer external sounds to mask the tinnitus. (harvard.edu)
  • If you notice any new pulsatile tinnitus, you should consult a clinician, because in rare cases it is a sign of a tumor or blood vessel damage. (harvard.edu)
  • Pulsatile tinnitus is different to regular tinnitus in that you may hear rhythmical noises that beat in time with your pulse. (amplifon.com)
Perfusion2
  • Although heart-lung machines and cardiac assist devices have been used successfully for acute and chronic cardiac support for decades, controversies still remain concerning the benefits of pulsatile and non-pulsatile perfusion. (elsevier.com)
  • Using these critical parameters may explain how excess energy is created by pulsatile flow and maintains perfusion through the microcirculation by ensuring capillary patency. (elsevier.com)
Arterial9
  • We hypothesize that arterial flow must provide a unique signal that is relevant for supporting arterial identity gene expression and is absent in veins. (unifr.ch)
  • Arterial endothelial cells exposed to pulsatile shear in vitro augmented arterial marker expression as compared with exposure to constant shear. (unifr.ch)
  • The expression of Gja5 correlated with arterial flow patterns: the redistribution of arterial flow provoked by vitelline artery ligation resulted in flow-driven collateral arterial network formation and was associated with increased expression of Gja5. (unifr.ch)
  • In the adult, increased flow drives arteriogenesis and the formation of collateral arterial networks in peripheral occlusive diseases. (unifr.ch)
  • We conclude that pulsatile shear patterns may be central for supporting arterial identity, and that arterial Gja5 expression plays a functional role in flow-driven arteriogenesis. (unifr.ch)
  • Colour should not be relied on alone to determine arterial or venous flow due to the colour scale setting can be flipped or reversed, or aliasing can occur. (openaccessgovernment.org)
  • Arterial flow is more pulsatile than venous. (openaccessgovernment.org)
  • AVF introduces pulsatile arterial blood flow into its venous limb and produces high luminal pressure gradient, which may have adverse effect on vascular remodeling. (elsevier.com)
  • In 1972, Aoyagi was investigating a noninvasive cardiac output device and discovered that arterial pulsatile "noise" interfering with the accurate dye dilution curve contains important information about the oxygenation of blood in a person's arteries. (ieee.org)
Venous1
  • Venous flow may require distal augmentation (by squeezing the forearm distal to the probe) to appreciate the blush of colour. (openaccessgovernment.org)
Blood38
  • Pulsatile blood flow effects on temperature distribution and heat transfer in rigid vessels. (duke.edu)
  • A simple model of a straight rigid blood vessel with unsteady periodic flow is considered. (duke.edu)
  • Rhythmic, intermittent propagation of a fluid through a blood VESSEL or piping system, in contrast to constant, smooth propagation, which produces laminar flow. (lookfordiagnosis.com)
  • Sclerotherapy supposes the use of a sclerosing agent, which scars the inflamed tissue, thus reducing the blood flow towards the haemorrhoid and attenuating both the cause and the symptoms of the haemorrhoids. (realkafka.ro)
  • Flow-induced blood damage plays an important role in determining the hemodynamic impact of abnormal blood flow, but quantifying of these effects, which are dominated by shear stresses in highly fluctuating turbulent flow, has not been feasible. (nature.com)
  • This study evaluated the novel application of turbulence tensor measurements using simulated 4D Flow MRI data with six-directional velocity encoding for assessing hemodynamic stresses and corresponding blood damage index (BDI) in stenotic turbulent blood flow. (nature.com)
  • In conclusion, this study demonstrated the feasibility of 4D Flow MRI based quantification of TVSS and BDI which are closely linked to blood damage. (nature.com)
  • Therefore, quantifying flow-induced blood damage can be useful for assessing the hemodynamic effects caused by obstructed blood flow, and could guide subsequent treatment or surgical interventions for patients. (nature.com)
  • Flow-induced blood damage is caused by hemodynamic stresses. (nature.com)
  • However, neither the rotational viscometer nor the stenotic nozzle flow can successfully recreate the hemodynamic environments for turbulent blood flow in the cardiovascular system. (nature.com)
  • Adhesion of isolated SSRBCs and whole blood during pulsatile flow was unaffected by protein kinase A (PKA) inhibition, and exposure of SSRBCs to pulsatile flow did not affect the intrinsic adhesive properties of SSRBCs. (functionalfluidics.com)
  • We conclude that low flow periods of the pulse cycle allow more adhesive interactions between sickle erythrocytes and VCAM-1, and sickle erythrocyte adhesion in the context of whole blood may better reflect physiologic cellular interactions. (functionalfluidics.com)
  • Despite pulsatile flow adaptability most microfluidic flow adhesion assays use flow delivery systems that drive continuous blood flow, similar to the earlier PPFA assays on which most of our understanding of SSRBC adhesive interactions is based. (functionalfluidics.com)
  • Additionally, the microvascular blood flow in patients with SCD has been shown to have a more pulsatile or periodic flow pattern compared to unaffected control patients [ 31, 35 ]. (functionalfluidics.com)
  • Pulsatile blood flow has been shown to have specific influences on cell behavior, such as increasing platelet adhesion to immobilized collagen and increasing cell-surface exposure of P-selectins [ 49 ]. (functionalfluidics.com)
  • Therefore, it is plausible that pulsatile blood flow may similarly augment adhesive interactions of SSRBCs and other cellular components of whole blood. (functionalfluidics.com)
  • We used three-dimensional modelling and simulation of blood flow through two arteries consisting of two stenosis each, one with the same radius for both the cases and the other with different radii for each case. (elsevier.com)
  • The type of blood flow was considered to be simple pulsatile in order to mimic the rhythmic pulses of the human heart. (elsevier.com)
  • This study considered blood flow models which is non-newtonian and solved the 3D laminar and unsteady NS Equations to extracted velocity profiles at 6 different locations in a blood vessel and shear strain rate for both cases. (elsevier.com)
  • This lesion continues to demonstrate bidirectional flow throughout the diastole, indicating blood flow through vessels arranged chaotically. (medscape.com)
  • A new model is used to analyze the fully coupled problem of pulsatile blood flow through a compliant, axisymmetric stenotic artery using the finite element method. (asme.org)
  • Your circulatory system (blood flow) and somatic movements (musculo-skeletal) produce the sounds. (phonak.com)
  • Examples include flow through blood vessels, pulsatile flow, and pattern formation. (oup.com)
  • Although FA is the state of the art in proving the existence of blood flow during interventions such as bypass surgery, it still lacks a quantitative blood flow measurement that could decrease the recurrence rate and postsurgical mortality. (frontiersin.org)
  • A current clinical routine for blood volume flow assessment involves the usage of an ultrasonic flow probe. (frontiersin.org)
  • Effect of trabeculectomy on pulsatile ocular blood flow. (bmj.com)
  • White matter damage due to pulsatile versus steady blood pressure differs by vascular territory: a cross-sectional analysis of the UK Biobank cohort study. (ox.ac.uk)
  • By measuring changes in light absorption at characteristic wavelengths during pulsatile blood flow generated by the heartbeat. (utwente.nl)
  • As suggested by clinical experience and pilot data, PPG can reliably detect the absence of pulsatile blood flow. (utwente.nl)
  • It's more likely to happen in older people, because blood flow tends to be more turbulent in arteries whose walls have stiffened with age. (harvard.edu)
  • Lymphatic vessels are highly analogous to blood vessels, although lymphatic flow characteristics and its effect on lymphatic endothelial cells (LECs) via mechanotransduction have been comparatively less examined. (umass.edu)
  • Mehra attributed this to the switch to a magnetically-levitated pump that reduces shear stress on blood cells and permits pulsatile flow. (medpagetoday.com)
  • The advantages of the percutaneous devices include speed of implant and no requirement for surgery, while the surgical devices provide more blood flow and likely more rapid recovery of organ function from shock. (medscape.com)
  • This allows blood to leak (hemorrhage) into the brain or surrounding tissues and reduces blood flow to the brain. (medlineplus.gov)
  • This stops the blood flow in the AVM and reduces the risk of bleeding. (medlineplus.gov)
  • This condition is often attributed to blood flow changes in the vessels near the ear, or to a specific condition such as a perforated eardrum or atherosclerosis. (amplifon.com)
  • MRI is also able to quantify the blood volume flow in the great vessels, the shunt volumes between the circularity sides and the function of the cardiac valves. (bme.hu)
  • Because the right coronary artery originates from the aorta, decreased LV output causes decreased right coronary blood flow and ischemia to the RV wall. (medscape.com)
Cerebrospinal fluid4
  • Clinical symptoms are predominantly due to hydrocephalus, which results from direct mechanical obstruction to the flow of cerebrospinal fluid (CSF) caused by an arachnoid granulation blockage from hemorrhage or CSF overproduction. (medscape.com)
  • Note the associated hydrocephalus and transependymal cerebrospinal fluid flow. (medscape.com)
  • Characterising spinal cerebrospinal fluid flow in the pig with phase-contrast magnetic resonance imaging. (bvsalud.org)
  • Detecting changes in pulsatile cerebrospinal fluid (CSF) flow may assist clinical management decisions, but spinal CSF flow is relatively understudied. (bvsalud.org)
Artery2
  • The purpose of this study was to compare the effect of pulsatile and nonpulsatile flow on the coagulation profile, liver and kidney function and also on the haemodynamics in patients undergoing coronary artery bypass grafting on CPB. (who.int)
  • Colour or Power Doppler may be utilised to determine if the pulsatile flow is consistent with an artery or vein. (openaccessgovernment.org)
Vitro3
  • Most in vitro flow adhesion assays measure SSRBC adhesion during continuous flow, although in vivo SSRBC adhesive interactions occur during pulsatile flow. (functionalfluidics.com)
  • In the current study, fluid flow was characterized in murine lymphatic collecting vessels using fluorescent microparticles to examine the phenotypic difference of LECs exposed to physiological flow conditions in vitro. (umass.edu)
  • LECs were exposed in vitro to pulsatile or steady static pressure conditions without flow. (umass.edu)
Intermittent1
  • Does a combination of fluid restriction and the use of oxytocin in a pulsatile fashion (intermittent boluses) for women requiring an induction, result in a reduction in the duration of labour, defined by the commencement of oxytocin until the birth of the neonate, when compared to a regime of fluid restriction with continuous oxytocin? (who.int)
Time-averaged3
  • The best discrimination between arteries and veins was obtained by calculating the maximal pulsatile increase in shear rate relative to the time-averaged shear rate in the same vessel: the relative pulse slope index (RPSI). (unifr.ch)
  • Although varying degrees of flow pulsatility have been observed in vivo, non-pulsatile (time-averaged) boundary conditions have traditionally been assumed in hemodynamic modeling, and only recently have pulsatile conditions been incorporated without completely characterizing their effect or importance. (emory.edu)
  • 30%, the relative error in hemodynamic predictions using time-averaged boundary conditions was less than 10% compared to pulsatile simulations. (emory.edu)
Endovascular1
  • Optimised passive marker device visibility and automatic marker detection for 3-T MRI-guided endovascular interventions: a pulsatile flow phantom study Passive paramagnetic markers on magnetic resonance imaging (MRI)-compatible endovascular devices induce susceptibility artifacts, enabling MRI-visibility and real-time MRI-guidance. (nano4imaging.com)
Vessels6
  • Pulsatile flow-induced shear stress in large vessels affects VE-Cadherin and Neuregulin-1 expression in endothelial cells. (aps.org)
  • however, in the larger vessels, shear stress is pulsatile. (aps.org)
  • reversal of flow occurs in the aorta and in large vessels, which produces significant time variation in the temperature profile. (duke.edu)
  • Summary: Flow dynamics in intracranial aneurysms and their adjacent parent vessels play important roles in the development and rupture of intracranial aneurysms. (ajnr.org)
  • Flow dynamics in intracranial aneurysms and their adjacent parent vessels are believed to play an important role in the development and rupture of intracranial aneurysms ( 3 ). (ajnr.org)
  • The most significant geometric features that influence fluid flow in lymphatic vessels are bi-leaflet valves present in each lymphangion. (umass.edu)
Boundary conditions2
  • In this study, 3D numerical simulations with both pulsatile and non-pulsatile boundary conditions were performed for 24 patients with different anatomies and flow boundary conditions from Georgia Tech database. (emory.edu)
  • It was found that flow pulsatility is the primary factor in determining the appropriate choice of boundary conditions, whereas the anatomic configuration and cardiac output had secondary effects. (emory.edu)
Waveform1
  • LECs were exposed to the midlymphangion flow waveform in a parallel plate flow chamber system and compared to cells cultured in static conditions. (umass.edu)
Versus2
  • Using a well-plate microfluidic flow adhesion system, we demonstrate that isolated SSRBCs adhere to vascular cell adhesion molecule (VCAM-1) at greater levels during pulsatile versus continuous flow. (functionalfluidics.com)
  • The effects of exposing LECs to steady versus pulsatile pressure of similar mean values have not previously been examined. (umass.edu)
Endothelial3
  • It is well known that endothelial cell behavior is modulated by flow-induced shear stress. (aps.org)
  • Fluid flow in the cardiovascular and lymphatic systems influences the phenotype of endothelial cells that line the interior to the vessel via mechanotransduction. (umass.edu)
  • Geometric features in a vessel such as curvature, bifurcation, and valves promote heterogeneous fluid flow profiles, inducing a heterogeneous endothelial phenotype within a vessel region. (umass.edu)
Velocity5
  • The other was to apply particle image velocimetry (PIV) software ( 5 , 6 ) to tagged MR images and to investigate whether this new technique, named tagged MR image velocimetry, could be used to calculate the flow velocity, vorticity, and shear strain in the replica. (ajnr.org)
  • We changed the flow volume of the pulsatile pump by using its control unit and measured the flow velocity several times by using the MR machine. (ajnr.org)
  • CSF flow and velocity were determined throughout a cardiac cycle. (bvsalud.org)
  • Linear mixed-effects models, with post-hoc comparisons, were used to identify differences in peak systolic/diastolic flow, and maximum velocity (cranial/caudal), across spinal levels and dorsal/ventral SAS. (bvsalud.org)
  • In anaesthetised and ventilated domestic pigs , spinal CSF has lower pulsatile flow and slower velocity wave propagation, compared to humans . (bvsalud.org)
Incompressible1
  • 1995 , " Finite Element Analysis of Incompressible and Compressible Fluid Flows With Free Surfaces and Structural Interactions ," Computers and Structures , Vol. (asme.org)
Continuous flow7
  • Pulsatile volume displacement pumps have evolved to continuous flow pumps, a whole new type of design for the long-term pumps(Slide 1). (medscape.com)
  • Pulsatile vs Continuous Flow VADs. (medscape.com)
  • The large volume displacement type of LVAD is the prototype of the first generation pumps, while an example of the newer second generation of continuous flow pump is the Heartmate II pump on the right.The HM II pump allows instantaneous adjustment of pump speed and LV unloading. (medscape.com)
  • Matching the individual patient to the optimal VAD can be challenging at times, but the new second generation of continuous flow pumps have proven to be quite versatile and can effectively support nearly any type of patient for any indication (Slide 5). (medscape.com)
  • The current lower limits of body surface area for VAD candidates has been reduced from 1.5 to 1.3 meters 2 with the continuous flow pumps. (medscape.com)
  • thus, newer "continuous-flow" devices have taken the place of pulsatile-flow VADs. (bvsalud.org)
  • Our analysis focusses on the two continuous-flow VADs that are the most relevant to the Quebec context: HeartMate II®, the device that is the most often used in Quebec, and HeartWare®, an emerging technology in Europe. (bvsalud.org)
Laminar4
  • The results showed that 4D Flow MRI underestimates the maximum principal shear stress of laminar viscous stress (PLVS), and overestimates the maximum principal shear stress of Reynolds stress (PRSS) with increasing voxel size. (nature.com)
  • Pressure drop results are found to compare well to an experimentally based theoretical curve, despite the assumption of laminar flow. (asme.org)
  • Laminar flow tube based flow gauge even capable of measuring pulsatile flow. (cens.com)
  • Propagación rítmica e intermitente de un fluido a través de un VASO SANGUÍNEO o un sistema de conductos, en contraposición a la propagación suave y constante de un flujo laminar. (bvsalud.org)
Vascular3
  • Pulsatile CPB is considered to be more physiological than nonpulsatile flow as the pulsatile energy ensures the patency of the vascular bed and mechanical motion of tissue fluid around the cell membrane, improves microcirculation and enhances diffusion. (who.int)
  • We placed the vascular model into the gantry of the MR machine and connected it with the pulsatile pump system by means of a silicon tube. (ajnr.org)
  • Certain flow conditions are associated with vascular dysfunction, and diseases such as atherosclerosis preferentially develop in areas of flow disturbance. (umass.edu)
Shear stress1
  • Western blots were performed to quantify the amount of VE-Cad and NRG-1 expressed by HUVECs after exposure to flow-induced shear stress. (aps.org)
VADs1
  • In 2011, the Ministry of Health and Social Services (MSSS) gave the Institut national d'excellence en santé et en services sociaux (INESSS) the mandate to perform an evaluation of implantable VADs. (bvsalud.org)
Obstruction1
  • Traumatic spinal cord injuries (SCI) often cause spinal cord swelling and subarachnoid space (SAS) obstruction, potentially causing pulsatile CSF flow changes. (bvsalud.org)
Metrics1
  • A correlation was introduced to relate wPI to the relative error in predicting the flow metrics with non-pulsatile flow conditions. (emory.edu)
Occlusion1
  • At the end of the infusion test, 2 ml of ringer¿s lactate solution was injected into the shunt prechamber of the patient while distal flow was blocked by temporary compression of the occlusion chamber that is distal to the valve. (fda.gov)
Measurements were made1
  • Flow measurements were made for inspiratory flow and pulsatile inspiratory flow. (cdc.gov)
Vivo2
  • To simulate in vivo flow conditions, laboratory-designed parallel plate flow adhesion (PPFA) assays were utilized to study sickle erythrocyte adhesion under physiologic flow conditions [ 2, 15, 46 ]. (functionalfluidics.com)
  • We analyzed factors related to flow, pressure and oxygenation in the chicken embryo vitelline vasculature in vivo. (unifr.ch)
Assessment1
  • The microfluidic flow adhesion bioassay used in this study may have applications for clinical assessment of sickle erythrocyte adhesion during pulsatile flow. (functionalfluidics.com)
Pump2
  • The replica also had a pulsatile flow pump system (Shelley Medical Imaging Technologies). (ajnr.org)
  • Pump replacement as a secondary endpoint also remained significantly lower than with the older, axial flow device (12 patients vs 57, 2.3% vs 11.3%, RR 0.21), Mandeep Mehra, MD, of Brigham and Women's Hospital in Boston, reported here at the American College of Cardiology meeting and simultaneously in the New England Journal of Medicine . (medpagetoday.com)
Comparative3
  • IMSEAR at SEARO: Comparative study of pulsatile and nonpulsatile flow during cardio-pulmonary bypass. (who.int)
  • Poswal P, Mehta Y, Juneja R, Khanna S, Meharwal ZS, Trehan N. Comparative study of pulsatile and nonpulsatile flow during cardio-pulmonary bypass. (who.int)
  • The comparative maximum flow ranges from 2.5 to 3.5 liters with the percutaneous devices and 5 to 6 liters with the surgically implanted temporary devices. (medscape.com)
Magnetic1
  • Analysis of spin-echo rephasing with pulsatile flow in 2D FT magnetic resonance imaging. (nih.gov)
Arteries1
  • In situ hybridization in normal and ligation embryos confirmed that Gja5 expression is confined to arteries and regulated by flow. (unifr.ch)
Quantification1
  • The accurate determination of the transit time and the quantification of the error allow the calculation of the error propagation onto the flow measurement. (frontiersin.org)
Steady flow2
  • Pulsatile inspiratory flow was found to be more realistic than steady flow in this model. (cdc.gov)
  • This study demonstrated that LECs showed increased intercellular gap formation when exposed to steady pressure and steady flow, but not pulsatile pressure and pulsatile flow of similar mean values. (umass.edu)
Parameters2
  • Further reductions in stenosis cross-sectional area, however, produce relatively little additional change in these parameters due to a concomitant reduction in flow rate caused by the losses in the constriction. (asme.org)
  • Participants received early postoperative ultrasound 5-7 days after surgery to collect parameters including diameters, flow rates, and volume at inflow and outflow sites. (elsevier.com)
Complex2
  • 2020) Adaptive feeding in the American oyster Crassostrea virginica: complex impacts of pulsatile flow during pseudofecal ejection events . (morgan.edu)
  • The resulting anatomy has complex and unsteady hemodynamics characterized by flow mixing and flow separation. (emory.edu)
Urine1
  • In conclusion we did not find any significant difference between pulsatile and nonpulsatile flow during CPB except the creatinine clearance and urine output were better in pulsatile group. (who.int)
Patients2
  • One hundred patients between 35 and 65 years of age with normal left ventricular function were randomly divided into two equal groups: Pulsatile (P) and nonpulsatile (NP). (who.int)
  • Unfortunately, less than 50% of patients with ruptured AAA present with the classic triad of syncope followed by back, flank, or abdominal pain and a pulsatile abdominal mass.[16] Up to 30-60% of patients with AAA are initially misdiagnosed. (medscape.com)
20221
  • Método: revisión integrativa, con búsqueda realizada en febrero de 2022 en cuatro bases de datos. (bvsalud.org)
20161
  • 2016) Restricted Gene Flow for Gadus macrocephalus from Yellow Sea Based on Microsatellite Markers: Geographic Block of Tsushima Current . (morgan.edu)
Patterns1
  • Gas and aerosol deposition efficiency in lung airways of humans and animals were investigated under two different airflow patterns: steady inspiratory flow and pulsatile inspiratory flow. (cdc.gov)
Hemodynamics1
  • Results show that the hemodynamics can be strongly influenced by the presence of pulsatile flow. (emory.edu)
Pressure3
  • An infusion study performed revealed that the baseline pressure was low and non-pulsatile. (fda.gov)
  • Pulsatile and steady pressure chambers were constructed to emulate normal lymphatic pressure and lymphedema-like pressure waveforms, respectively. (umass.edu)
  • Flow structures, energy dissipation rates and pressure drops were compared under rest and simulated exercise conditions. (emory.edu)
Vessel2
  • To confirm placement, either a 'bubble study' with agitated saline may be performed or Colour (or Power) Doppler utilised to visualise saline flow through the cannulated vessel. (openaccessgovernment.org)
  • Characterization of the flow field in a vessel affected by lymphedema in a CLEC2-deficient mouse was found to be quasi-steady with loss of pulsatility. (umass.edu)
Fluid flow3
  • This is a readable and attractively presented overview of fluid flow in biological systems. (oup.com)
  • Fluid flow adjacent to the valve sinus was virtually static, while the wall of the midlymphangion experienced net-antegrade pulsatile flow with a small degree of retrograde flow. (umass.edu)
  • Lymphedema is a notable condition that may result from valvular dysfunction and can significantly alter fluid flow and likely cause phenotypic changes in LECs via mechanotransduction. (umass.edu)
Ventricular1
  • Retrograde flush of the ventricular catheter was performed during temporary compression of the siphon-control device, a manoeuvre which blocks distal flow. (fda.gov)
Clinical3
  • Pulsatile Flow Promotes Adhesion in Sickle Cell Disease: Clinical Application of a Microfluidic Bioassay. (functionalfluidics.com)
  • As a result, microfluidic-based flow adhesion assays provide a platform for clinical bioassays measuring SSRBC adhesive properties during physiologic flow conditions. (functionalfluidics.com)
  • The accuracy of the latest state-of-the-art clinical flow probe is ±10% ( Transonic, 2019 ). (frontiersin.org)
Study1
  • This study provides baseline CSF flow at spinal levels relevant for future SCI research in this animal model . (bvsalud.org)
Biological1
  • Biorheology is an international interdisciplinary journal that publishes research on the deformation and flow properties of biological systems or materials. (semcs.net)