It is well known that the angiographic no-reflow phenomenon occurs after intervention in degenerated saphenous vein grafts. In these cases, distal embolization of plaque or thrombus from the lesion site is the likely mechanism.11,12⇓ Webb et al13 reported the presence of particulate material in 21 of 23 distal protection device procedures, in which pathological examination revealed the presence of particles with a necrotic core of cholesterol clefts, lipid-rich macrophages, and fibrins.. In patients with AMI, Sutsch et al14 have reported that plaque debris consisting of a necrotic core, inflammatory cells, cholesterol debris, and old and fresh thrombi are often retrieved from the distal portions of infarct-related arteries after direct angioplasty.. In the present study, we demonstrate that the angiographic no-reflow phenomenon after primary angioplasty or stenting in patients with AMI correlates with lesion IVUS morphology. The morphological features of the lipid pool-like image are similar ...
Background: It was reported that patients with acute coronary syndrome (ACS) frequently have vulnerable plaques in the remote coronary arteries, suggesting ACS is a part of the pan-coronary process and systemic inflammation. MDCT allows us to assess not only culprit lesion but also whole coronary trees. However in patients with ACS, the impact of plaque morphology in remote coronary arteries and C-reactive protein (CRP) on the occurrence of slow flow phenomenon (SF) during PCI is still unclear.. Methods: Consecutive 116 patients (69±9 years, 78% males) with acute coronary syndrome diagnosed by 128-slice dual source MDCT before coronary interventions were enrolled. Non-culprit lesions were defined as plaques with more than 25% diameter stenosis measured by quantitative angiography that had not been treated. The CT value of plaque and plaque morphology in culprit and non-culprit lesions and serum CRP level were compared between patients with and without SF during PCI.. Results: Thirty six ...
p,For patients with acute myocardial infarction (MI), the immediate therapeutic goal is to establish the patency of the infarct-related artery. Prolonged myocardial ischemia, however, often breaks down the coronary microvasculature, and the flow to the infarct myocardium may be markedly reduced. This is called the no-reflow phenomenon. This phenomenon is important not solely because it correlates with infarct size but because it provides additional prognostic information. With recent advances in imaging modalities, the no-reflow phenomenon is observed more frequently than when clinical judgment alone is used. Patients with this phenomenon are associated with poor functional and clinical outcomes. Now, the no-reflow phenomenon can be a parameter with which to predict high-risk patients. The focus of reperfusion therapy has shifted toward the improvement of myocardial perfusion. The improvement of myocardial perfusion could promote the functional recovery of viable muscle and reduce infarct ...
The underlying mechanisms behind the effect of atorvastatin on patients with coronary slow flow (CSF) remain largely unknown. To investigate the possible underlying molecular mechanisms 108 patients were divided into atorvastatin group and control group. Coronary flow was quantified according to corrected TIMI frame count (CTFC). Serum high sensitivity C-reactive protein (hs-CRP), lipids, ET-1, interleukin (IL)-6, NO, circulating endothelial progenitor cell (cEPC) count, adhesion, migration and proliferation were measured in pretreatment and post-treatment. After respective treatment, the atorvastatin group had significantly decreased levels of TC, TG, LDL-C, hs-CRP, ET-1 and IL-6 and increased NO compared to the control group. The atorvastatin group had a more significant improvement of CTFC, effective rate, cEPC number, EPC adhesion, migration and proliferation compared to the control group. In conclusion, atorvastatin can be used in treatment of CSF by suppressing inflammation and improving ...
Liu, Yong, Islam, Shariful, Chow, Clara K., Chen, Shiqun, Siddiqui, Muhammad Umer, Li, Qiang, Lin, Kai-yang, Wang, Kun, Sun, Guoli, Zhou, Ying-Ling, Chen, Jiyan and Brieger, David 2017, Immediate versus deferred stenting for patients undergoing primary or emergent percutaneous coronary intervention: Protocol for a systematic review and meta-analysis, Medicine, vol. 96, no. 47, pp. 1-5, doi: 10.1097/MD.0000000000008477. ...
The First Symposium on Turbulence and Shear Flow Phenomena was held September 12-15, 1999 in Santa Barbara, California. This new symposium series is the successor to the highly regarded series of Symposia on Turbulent Shear Flows, which concluded with the 11th biennial conference in 1997. The Symposium aims to be the premier forum for presentation of fundamental and applied research in turbulence. Submissions were solicited in traditional turbulence research areas along with five areas selected for special emphasis: biological and medical flows, multiphase flows, reacting turbulent flows, geophysical and environmental flows, and flow control/MEMS. Five speakers were invited to give review talks covering some aspect of these areas. Over 320 extended abstracts were submitted in response to the call for papers. Each abstract was evaluated by two members of the Advisory and Executive Committees and two members of the Papers Committee. Most of the abstracts were of high quality, requiring many difficult
TY - GEN. T1 - Computer simulation of flow phenomena in distensible arterial bifurcation models. AU - Perktold, Karl. AU - Peter, Reinfried Odo. AU - Gürtl, Raimund. PY - 1992. Y1 - 1992. M3 - Conference contribution. SN - 88-7958-001-9. SP - 377. EP - 381. BT - Proceedings - MEDICON. PB - CNR. CY - Pisa. ER - ...
Chronic inhibition of cyclic GMP phosphodiesterase 5A prevents and reverses endothelial dysfunction and oxidative stress associated with the metabolic syndrome. Delphine, Behr-Roussel; Oudot, Alexandra; Caisey, Stephanie; Le Coz, Olivier; Gorny, Diane; Bernabé, Jaques; Wayman, Chris; Alexandre, Laurent; Giuliano, Francois // BMC Pharmacology;2007 Supplement 1, Vol. 7, pS28 An abstract of the paper "Chronic Inhibition of Cyclic GMP Phosphodiesterase 5A Prevents and Reverses Endothelial Dysfunction and Oxidative Stress Associated With the Metabolic Syndrome," by Behr-Rousse Delphine, Alexandra Oudot, and colleagues is presented. ...
TY - JOUR. T1 - Tissue Inflammation Impairs Tissue-Level Perfusion and Promotes Left Ventricular Remodeling in Patients With Acute Myocardial Infarction. AU - Nishida, Yuya. AU - Itoh, Hiroshi. AU - Iwakura, Katsuomi. AU - Tanaka, Kouji. AU - Kawano, Shigeo. AU - Okamura, Atsunori. AU - Maekawa, Yoshinori. AU - Inoue, Kouichi. AU - Fujii, Kenshi. AU - Hori, Masatsugu. PY - 2005. Y1 - 2005. N2 - Background. C-reactive protein (CRP) level and monocytosis are associated with left ventricular (LV) remodeling in patients with AMI. Methods. One hundred twenty-nine consecutive patients with the first acute myocardial infarction (AMI) underwent myocardial contrast echocardiography (MCE) 2 weeks after successful reperfusion. Results. LV end-diastolic volume index (LVEDVI) at pre-discharge was significantly higher in the no-reflow group than the reflow group (64±17 vs. 58±11 mL/m2, p, 0.01). The no-reflow group had a higher CRP level and peak monocyte counts than the reflow group (9.5±5.2 vs. 5.8±3.5 ...
A 41 year old male hypertensive smoker presented with acute abdominal pain and transient widespread ST elevation on the ECG. Coronary angiography (panel A) revealed a mobile opacity in the proximal left main stem (arrow) and a slow flow phenomenon in the left anterior descending artery. Treatment was given with aspirin, clopidogrel, low molecular weight heparin and a tirofiban infusion over three days. Repeat angiography showed identical appearances in the left main stem with normal flow in the left anterior descending artery. Intravascular ultrasound of the left main stem (panel B) showed a non-occlusive atherosclerotic plaque (X) with adherent thrombus (Y). An attempt to aspirate the thrombus using the Rescue thrombosis management system failed. The lesion was therefore treated with stenting using a 4.5 × 13 mm Ultra bare metal stent, post-dilated to 5 mm (panels C and D). The patient made an uneventful recovery. Repeat angiography is planned at four months.. ...
One of the major limitations of reperfusion therapy in acute myocardial infarction (AMI) is the presentation of no-reflow phenomenon. In 25 to 30% of patients with AMI, myocardial blood flow is occasionally profoundly reduced, even after coronary recanalisation, because of microvascular dysfunction - so-called no-reflow phenomenon. Patients with this phenomenon are regarded as a high risk group among patients with reperfused AMI. Clinical studies using myocardial contrast echocardiography have demonstrated that intracoronary injection of calcium antagonists or potassium channel agonists in conjunction with coronary reperfusion can augment myocardial blood flow and that this was associated with better functional and clinical outcomes than with percutaneous transluminal coronary angioplasty alone. Thus, it is possible to prevent reperfusion injury and improve cardiac function using a adjunctive pharmacological intervention, either intravenously or by infusion directly into the coronary artery ...
A detailed aerodynamic study of a transonic, high-throughflow, single-stage compressor is presented. The compressor stage was comprised of a low-aspect-ratio rotor combined alternately with two different stator designs. Both experimental and numerical studies are conducted to understand the details of the complex flow field present in this stage. Aerodynamic measurements using high-frequency, Kulite pressure transducers and conventional probes are compared with results from a three-dimensional viscous flow analysis. A steady multiple blade row approach is used in the numerical technique to examine the detailed flow structure inside the rotor and the stator passages. The comparisons indicate that many flow field features are correctly captured by viscous flow analysis, and therefore unmeasured phenomena can be studied with some level of confidence.. ...
A series of large eddy simulations of plane Couette flow has been performed for Reynolds numbers between 750 and 3750. Three different models were used for the sub-grid scale stresses, and the results were found to be in reasonable agreement with existing data. The results were used to calculate Cμ, the coefficient in the standard k−ε turbulence model. It was found that in the near-wall region, significantly lower values of this coefficient were predicted, compared to correlations based on channel flow. One possible explanation could be that the boundary has a greater influence on the turbulence in the case of Couette flow in which there is no mean pressure gradient.. ...
The slow coronary flow phenomenon (SCF), a condition described by the presence of inappropriate delay in the progression of intracoronary contrast during angiography in the absence of stenoses, has been shown in some patients presenting with chest pa
Baseline and procedural characteristics are described in the table below. Perforation occurred in 0.9% (n=1), dissection occurred in 1.8% (n=2), and no-reflow phenomenon occurred in 0.9% of cases (n=1). There were no cases of bleeding complications, emergent bypass, 30-day MI, 30-day TVR, or stent thrombosis. 1 (0.9%) patient had a stroke within 30 days of PCI. Restenosis occurred in 3.6% of patients (n=4). 30 day mortality occurred in 1.8% of patients (n=2) due to non-cardiac causes from post-operative complications from non-cardiac surgery. ...
The performance of a centrifugal pump or compressor system has often been investigated on an overall basis for a wide range of operations and these investigations have, in the past, resulted in some remarkable technical advances. Detailed and penetrating studies of both the rotor and the components up and downstream are essential to obtain a knowledge of the critical areas and to increase further the efficiency of the system. In this study one problem area, the flow in radial diffusers in the absence of unsteady flow, is isolated and an extensive analytical and experimental study concerning this has been undertaken. In the absence of wakes from the impeller or other unsteady flow phenomena, the formation of a boundary layer on the side walls of the diffuser is the main cause of a loss in diffuser efficiency. The boundary layers which are three dimensional in character are investigated for several inlet conditions, and the theoretical results are compared with those of the experiments; the ...
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Date: Thu, 6 Jul 95 10:43:16 EDT From: dipalma at sky.com (Jim Dipalma) Subject: Re: Lauter Flow, Brewing 2 batches Hi All, In HBD#1774, Dave Bradley asks: ,What is the affect of starting and stopping the flow from the lauter , tun during the initial recirculation period? , ,My technique has been to stop the slow flow while returning the , still cloudy sweet wort already collected back the top of , the grain bed, and pseudo-clarity seems to take more time , for me to achieve than for others (all-grain time thread). FWIW, what I do is place a 3 quart saucepan inside a 5 gallon pot, and run the wort into the saucepan. When theres about 2 quarts in the saucepan, I return the cloudy wort to the top of the tun, taking care to disturb the grainbed as little as possible, while the wort continues to run into the larger pot. When the runoff starts to clear, I return whatever wort is in the larger pot to the top of the tun. While the wort is being runoff, pressure is generated inside the lauter tun ...
Methods and results In 90-min ischaemia and 3-h reperfusion model, Minipigs were randomly assigned to four groups (n=8 in each group): (1) Sham; (2) Control; (3) TXL: 0.05 g·kg−1 of TXL was gavaged 1 h prior myocardial ischaemia; (4) TXL+H-89 (1.0 μg·kg−1·min−1, an inhibitor of PKA). TXL significantly decreased creatine kinase (CK) activity, reduced the infarct size from 78.5% to 59.2% and no-reflow area from 48.6% to 9.5% (p,0.05), while H-89 completely abolished the reduction of CK activity and necrosis size, and partially diminished the reduction of no-reflow size. TXL enhanced the PKA activity in ischaemic myocardium, increased the expression of PKA, Thr 198 p-PKA and Ser 635 p-eNOS in no-reflow area, and upregulated the expression of eNOS and Ser 1179 p-eNOS in reflow area. H-89 repressed the enhancement of PKA activity and the upregulation of eNOS and Ser 635 p-eNOS, but without great inhibition on the expression of PKA and Thr 198 p-PKA in no-reflow area, and even stimulated the ...
Objective: SCUBE1 [signal peptide-CUB (complement C1r/C1 s)-EGF (epidermal growth factor)-like domain-containing protein 1] might function as a novel platelet-endothelial adhesion molecule and play pathological roles in cardiovascular biology. Acute myocardial infarction is one of the most common causes of death in modern society. The concept of no reflow (NR) refers to a state of myocardial tissue hypoperfusion in the presence of a patent epicardial coronary artery. The main mechanisms of this phenomenon are thought to be high platelet activity and much thrombus burden. So, we researched the role of SCUBE1 in the pathogenesis of NR ...
Boob Scoop: When a baby breastfeeds, she can comfort suck after a feeding to help herself settle. However, with a bottle she may appear to still be hungry when all she really needs is more sucking time. A slow flow bottle nipple helps with this because it offers the baby an opportunity for additional sucking time and a chance for the baby to realize that she is full. A slow flow bottle can be particularly helpful when a baby is in daycare: a mom may begin to doubt her milk supply if her baby is drinking more than the she is pumping at work. But it may not be that the baby needs more breastmilk in the bottle but rather that she needs more sucking time. Besides using a slow flow bottle nipple, a pacifier or other soothing methods, like being carried in a sling or carrier, can help a baby to settle after a feeding.. Sharen Medrano, Yummy Mummy Support Group IBCLC (www.nycbreastfeeding.com) ...
During the initial development of microvascular tissue transfer techniques, several vasodilating agents first used with axial flaps for salvage or "pharmacologic delay"44,45 (i.e., attempting pharmacologically to induce resistance to acute ischemia), were used for similar purposes in free tissue transfer.9 Use of these drugs (e.g., isoxuprine) has decreased with increasing experience with microsurgical procedures. Evidence has accumulated demonstrating that success in uncomplicated procedures does not depend on the use of systemic vasodilators. 30,31 Experience with tissues subjected to trauma and prolonged or repeated ischemia, as in cases of multiple anastomotic revisions, led to recognition of the "no-reflow phenomenon" as a microsurgical complication.10 This phenomenon had been reported earlier in ischemic organ transplants. Functionally, the no-reflow phenomenon is a state in which the microcirculation distal to a microvascular arterial anastamosis no longer functions as a patent bed. ...
Longitudinal extent of lipid pool assessed by optical coherence tomography predicts microvascular no-reflow after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction
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Electrostatic precipitators (ESPs) are now being tasked with simultaneously removing particulate matter (PM) and trace gas-phase pollutants such as mercury released during coal combustion. This represents a significant expansion of their original operational mission, one which is not captured by decades old quasi-1-D analytical expressions developed from first principles for predicting PM removal alone. At the same time, technological advances in ESP power supplies have led to steady increases over the years in the applied voltage achievable in new or refurbished ESPs. In light of these industry trends, the present study extends our previous study to examine the multiphase flow phenomena that may occur during such ESP operations, specifically the effects of electrohydrodynamic (EHD) fluid flow phenomena that can emerge when electrical current densities are high and/or fluid velocities are low. The results show good agreement at low current densities between the present numerical simulation results and
Transcriptional activity of tumor necrosis factor-alpha gene in peripheral blood mononuclear cells in patients with coronary slow flow
The presence of no-reflow in patients with acute myocardial infarction has been found to be a predictor of adverse events, with higher incidence of left ventricular (LV) remodelling, congestive heart failure, and death. An initial study by Wu et al. (n. 44; follow-up 16 months) demonstrated that patients with MVO had more cardiovascular events (45% versus 9%, P 0.016) independently of the total infarct size (6). Since then, several studies have succeeded in demonstrating such a correlation. A larger study by Hombach et al. (20) found that infarct size, MVO, LV end-diastolic volume, and EF predicted major adverse cardiac events (MACE), with MVO being the strongest predictor (13.2% more events). Cochet et al (21) showed that MVO and the Global Registry of Acute Coronary Events (GRACE) score were significant predictors of MACE (odds ratio [OR], 8.7; CI, 3.6 to 21.1; P,0.001; OR, 2.8; CI, 1.3 to 6; P,0.01, respectively). Nijveldt et al. (22) examined the relation between angiographic, ...
The ability to accurately model flow in subsurface formations enables the efficient production and optimal management of key resources such as oil and natural gas. Reliable subsurface flow models will also be required for the design and operation of geologic CO2 storage processes. My students and I pursue a number of research areas involving the simulation of multiphase subsurface flow phenomena. Some of the specific areas we study are the optimization of well placement and well settings, the upscaling (or coarse-graining) of detailed geological descriptions for flow simulation, reduced-order modeling, flow in fractured or faulted systems, CO2 sequestration modeling, and general numerical discretization and gridding issues. Many of our studies involve the development of new computational methods able to accurately and efficiently represent the effects of geological complexity on subsurface flow. Another main focus is "closed-loop" reservoir modeling, in which we employ computational optimization ...
6 Easy Ways To Lower Your Blood Pressure Nicholls said. We also saw a bit of a trend toward regression in atherosclerosis. But our primary endpoint -- a decrease in the volume of disease in the artery -- did not meet statistical significance. Although not a primary endpoint, the researchers did identify a decrease in…