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Percutaneous left atrial appendage (LAA) closure (LAAC) was developed as a nonpharmacologic alternative to oral anticoagulants (OACs) in patients with atrial fibrillation (AF) who are at an increased risk for stroke or systemic embolism. The Watchman device permanently seals off the LAA to prevent thrombi from escaping into the circulation. Previous randomized trials have established the safety and efficacy of LAAC compared to warfarin. However, direct OACs (DOACs) have become the preferred pharmacologic strategy for stroke prevention in patients with AF, and there is limited data comparing Watchman FLX to DOACs in a broad AF patient population. CHAMPION-AF is designed to prospectively determine whether LAAC with Watchman FLX is a reasonable first-line alternative to DOACs in patients with AF who are indicated for OAC therapy. A total of 3,000 patients with a CHA2DS2-VASc score ≥2 (men) or ≥3 (women) were randomized to Watchman FLX or DOAC in a 1:1 allocation at 142 global clinical sites. Patients in the device arm were to be treated with DOAC and aspirin, DOAC alone, or DAPT for at least 3 months postimplant followed by aspirin or P2Y12 inhibitor for 1-year. Control patients were required to take an approved DOAC for the duration of the trial. Clinical follow-up visits are scheduled at 3- and 12-months, and then annually through 5 years; LAA imaging is required at 4 months in the device group. Two primary end points will be evaluated at 3 years: (1) composite of stroke (ischemic/hemorrhagic), cardiovascular death, and systemic embolism compared for noninferiority, and (2) nonprocedural bleeding (International Society on Thrombosis and Haemostasis [ISTH] major and clinically relevant nonmajor bleeding) tested for superiority in the device arm against DOACs. The third primary noninferiority end point is the composite of ischemic stroke and systemic embolism at 5 years. Secondary end points include 3- and 5-year rates of (1) ISTH-defined major bleeding and (2) the composite of cardiovascular death, all stroke, systemic embolism, and nonprocedural ISTH bleeding. This study will prospectively evaluate whether LAAC with the Watchman FLX device is a reasonable alternative to DOACs in patients with AF. NCT04394546 [ABSTRACT FROM AUTHOR]

Intracardiac echocardiography (ICE) is increasingly used to guide left atrial appendage closure (LAAC). The aim of this study was to investigate the efficacy and safety of ICE-guided LAAC with the Watchman FLX device. The ICE LAA (I Can See Left Atrial Appendage) study was a prospective, multicenter study with independent adjudication of echocardiographic data by a core laboratory and clinical events by a clinical events committee. Patients with atrial fibrillation with CHA 2 DS 2 -VASc scores ≥2 and clinical indications for LAAC were eligible. Preplanning with either cardiac computed tomography or transesophageal echocardiography (TEE) within 7 days prior to LAAC was mandatory. Intraprocedural ICE was carried out from the left atrium. The primary outcome was the rate of significant peridevice leaks (>5 mm) at 45-day TEE. A total of 100 patients were enrolled. The mean age was 76 ± 8 years, the mean CHA 2 DS 2 -VASc score was 4.0 ± 1.5, and the mean HAS-BLED score was 2.5 ± 0.9. The incidence of the primary outcome of significant peridevice leak (>5 mm) was 0%; all patients evaluated by TEE at 45 days had effective LAAC. All patients received Watchman FLX devices, and technical success was 100%. The number of devices per case was 1.0 ± 0.1. ICE successfully guided the assessment of device release criteria, including device compression (19.2% ± 7.1%; recommended range: 10%-30%). No subject required conversion to TEE. Procedural complications were 4 access-site bleeds. There was no stroke, transient ischemic attack, systemic embolization, pericardial effusion, device embolization, or device-related thrombus during the procedure or 45-day follow-up. ICE can be used to successfully guide LAAC with the Watchman FLX, with excellent procedural success, a high rate of effective LAAC, and minimal periprocedural complications. (I Can See Left Atrial Appendage [ICELAA] Clinical Study; NCT04196335) [Display omitted] [ABSTRACT FROM AUTHOR]

Background: While extended dual antiplatelet therapy (DAPT) with aspirin and a platelet (P2Y12) inhibitor after percutaneous coronary intervention (PCI) reduces the risk of stent thrombosis (ST) and myocardial infarction (MI), it also increases bleeding. Newer generation drug-eluting stents with bioabsorbable polymer coatings may reduce thrombotic events and allow abbreviated DAPT in selected patients. The EVOLVE Short DAPT study is designed to evaluate the safety of 3-month DAPT in high bleeding risk subjects treated with the SYNERGY bioabsorbable polymer everolimus-eluting stent.Trial Design: EVOLVE Short DAPT is a prospective, single-arm, international study that enrolled 2009 high risk bleeding subjects (defined as age ≥75 years, chronic anticoagulation, major bleeding within 12 months, history of stroke, renal insufficiency/failure, or thrombocytopenia) who underwent PCI with the SYNERGY stent. Subjects presenting with acute MI or complex lesions were excluded. After 3 months treatment with DAPT (except those on anticoagulant in whom aspirin is optional), subjects free from stroke, MI, revascularization or ST will be eligible to discontinue P2Y12 inhibitor, but continue aspirin. Co-primary endpoints assessed between 3-15 months are: i) death/MI compared for non-inferiority with propensity-adjusted historical group receiving 12-month DAPT, and ii) definite/probable ST compared to a performance goal. The secondary endpoint is the rate of bleeding in subjects not receiving chronic anticoagulation compared for superiority against a propensity-adjusted historical control.Conclusion: The EVOLVE Short DAPT study will prospectively define the safety of DAPT discontinuation at 3 months in high bleeding risk patients treated with the SYNERGY stent. [ABSTRACT FROM AUTHOR]

This white paper provides a summary of presentations, discussions and conclusions of a Thinktank entitled "The Role of Endpoint Adjudication in Medical Device Clinical Trials". The think tank was cosponsored by the Cardiac Safety Research Committee, MDEpiNet and the US Food and Drug Administration (FDA) and was convened at the FDA's White Oak headquarters on March 11, 2016. Attention was focused on tailoring best practices for evaluation of endpoints in medical device clinical trials, practical issues in endpoint adjudication of therapeutic, diagnostic, biomarker and drug-device combinations, and the role of adjudication in regulatory and reimbursement issues throughout the device lifecycle. Attendees included representatives from medical device companies, the FDA, Centers for Medicare and Medicaid Services (CMS), end point adjudication specialist groups, clinical research organizations, and active, academically based adjudicators. The manuscript presents recommendations from the think tank regarding (1) rationale for when adjudication is appropriate, (2) best practices establishment and operation of a medical device adjudication committee and (3) the role of endpoint adjudication for post market evaluation in the emerging era of real world evidence. [ABSTRACT FROM AUTHOR]

We determine the electron and hole mobility edges in amorphous polyethylene (PE) by calculating the boundary between localized and delocalized states in energy space. First, the molecular structure is simulated with molecular dynamics simulations. Then, the electronic structure is calculated with density functional theory. For the calculation of the mobility edge, we use two approaches, the Inverse Participation Ratio, and a new method based on percolation theory. They turn out to provide the same results; the electron and hole mobility edges are <0.05 eV and 0.25 eV away from the respective band edge, respectively. [ABSTRACT FROM AUTHOR]

Objectives: The current study tested the hypothesis that glucose utilization differs between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), and investigated potential mechanisms for such a finding. Background: VAT burden correlates better with cardiovascular risk than does SAT burden. Beyond volumetric measurement, glucose uptake in adipose tissue (AT) might reflect metabolic activity and provide pathophysiologic insight and aid risk stratification. Methods: We retrospectively studied tissue-specific glucose uptake in vivo in clinically obtained whole-body fluorodeoxyglucose positron emission tomography (FDG-PET) scans in humans. We also assessed glucose uptake in vitro, using stromal vascular cells isolated from SAT and VAT of diet-induced obese C57BL/6 mice. Quantitative polymerase chain reaction (PCR) evaluated the expression of multiple genes involved in cellular glucose metabolism, including glucose transporters (GLUT-1, -3, and -4) and hexokinases (HK-1 and -2) in SAT and VAT of obese C57BL/6 mice. Results: We analyzed whole-body FDG-PET scans from 31 obese and 26 lean patients. VAT exhibited higher FDG uptake compared with SAT (p < 0.0001) independent of age, sex, body mass index, comorbidities, and medications. To investigate mechanisms underlying this observation, we studied glucose uptake in the stromal vascular cell fraction of AT, which is rich in inflammatory cells. Stromal vascular cells from VAT of diet-induced obese C57BL/6 mice exhibited higher glucose uptake than those from SAT (p = 0.01). Evaluation of expression of glucose transporters (GLUT-1, -3, and -4) and hexokinases (HK-1 and -2), revealed increased expression of HK-1 in VAT-derived compared with SAT-derived stromal vascular cells, and also in visceral versus subcutaneous unfractionated AT. Conclusions: In humans in vivo, VAT has increased glucose uptake compared with SAT, as determined noninvasively with FDG PET imaging. Differential stromal metabolic activity may be 1 mechanism underlying differences in metabolic activity of visceral and subcutaneous AT. [Copyright &y& Elsevier]

Abstract: In the framework of a two-moment photo-hydrodynamic modelling of radiation transport, we introduce a concept for the determination of effective radiation transport coefficients based on the minimization of the local entropy production rate of radiation and (generally nongrey) matter. The method provides the nonequilibrium photon distribution from which the effective (variable) absorption coefficients and the variable Eddington factor (VEF) can be calculated. For a single band model, the photon distribution depends explicitly on the frequency dependence of the absorption coefficient. Without introducing artificial fit parameters, multi-group or multi-band concepts, our approach reproduces the exact results in both limits of optically thick (Rosseland mean) and optically thin (Planck mean) media, in contrast to the maximum entropy method. Also the results for general nonequilibrium radiation between the limits of diffusive and ballistic photons are reasonable. We conjecture that the reason for the success of our approach lies in the linearity of the underlying Boltzmann equation of the photon gas. The method is illustrated and discussed for grey matter and for a simple example of nongrey matter with a two-band absorption spectrum. The method is also briefly compared with the maximum entropy concept. [Copyright &y& Elsevier]

Abstract: A C1019T polymorphism in the human connexin37 (hCx37) gene has been associated with cardiovascular risk, but it remains debatable whether the 1019C or the 1019T allele carries this risk. Here, we investigated whether these allelic variants are differentially predictive of increased risk for coronary artery disease (CAD) and myocardial infarction (MI). A total of 781 Swiss participants, including 597 patients diagnosed with CAD, 50% who reported previous MI, and 184 control subjects were genotyped. Patients in the +CAD group had a higher frequency of the Cx37-1019C allele (70.3% versus 65.0%, p =0.004). Multivariate analysis showed that the hCx37-C1019T polymorphism is an independent predictor of CAD (odds ratio=2.13, confidence interval=1.31–3.46 and p <0.01). Moreover, this polymorphism is not associated with any of the other characteristics examined, including gender, age, body-mass-index, diabetes, total/HDL/LDL-cholesterol, triglycerides, apoA-I, apoB, hypertension and cigarette smoking. In comparison with the −CAD group, we observed an increase of the Cx37-1019C allele in the +MI +CAD subgroup (71.2% versus 65.0%, p =0.002) but not in the −MI +CAD subgroup. Allelic frequency comparisons of these three subgroups predicted that this polymorphism is also an independent risk factor for MI. In conclusion, our results reveal the importance of screening the Cx37-1019C allele for both CAD and MI risk assessments. [Copyright &y& Elsevier]

The prevalence of and outcomes associated with different antithrombotic strategies after left atrial appendage occlusion (LAAO) are not well described. This study sought to evaluate patterns of antithrombotic medication strategies at discharge following LAAO with the Watchman FLX device in real-world practice and to compare the risk of adverse events among the different antithrombotic regimens. The authors evaluated patients in the NCDR (National Cardiovascular Data Registry) LAAO Registry who underwent LAAO with the second-generation LAA closure device between 2020 and 2022. They grouped patients by mutually exclusive discharge antithrombotic strategies and compared the rates of adverse events at 45 days and 6 months using multivariable Cox proportional hazards regression. Among 53,878 patients undergoing successful LAAO with the second-generation LAA closure device, the most common antithrombotic discharge regimens were direct oral anticoagulant (DOAC) plus aspirin (48.3%), DOAC alone (22.6%), dual antiplatelet therapy (8.1%), warfarin plus aspirin (7.7%), and DOAC plus P2Y 12 inhibitor (4.9%). In multivariate analysis, DOAC alone had a lower rate of major adverse events and major bleeding at 45 days of follow-up compared with DOAC plus aspirin (major adverse events: HR: 0.78; 95% CI: 0.68-0.91; major bleeding: HR: 0.69; 95% CI: 0.60-0.80). These differences persisted at 6 months. Warfarin without aspirin also showed lower rates of major bleeding at both time points. No differences were seen in stroke/transient ischemic attack or device-related thrombus. In real-world U.S. practice, discharge on DOAC alone or warfarin alone was associated with a lower rate of adverse events compared with DOAC plus aspirin. [ABSTRACT FROM AUTHOR]

Highlights • rs-fMRI benefits enormously from sampling above the cardiac cycle Nyquist frequency. • Broadening the spectral width significantly improves SNS and TRT for rs-fMRI data. • Filtering the cardiac and respiratory bands significantly improves the ICA analysis. • 3 min SMS-EPI scan provides comparable levels of SNS and TRT as that of a 10 min EPI. Abstract Background Recent advancements in simultaneous multi-slice (SMS) imaging techniques have enabled whole-brain resting-state fMRI (rs-fMRI) scanning at sub-second temporal resolution, providing spectral ranges much wider than the typically used range of 0.01–0.1 Hz. However, the advantages of this accelerated acquisition for rs-fMRI have not been evaluated. New method In this study, we used SMS Echo Planar Imaging (EPI) to probe whole-brain functional connectivity with a short repetition time (TR = 350 ms) and compared it with standard EPI with a longer TR of 2000 ms. We determined the effect of scan length and investigated the temporal filtration strategies that optimize results based on metrics of signal-noise separation and test-retest reliability using both seed-based and independent component analysis (ICA). Results We found that use of either the entire frequency range of 0.01–1.4 Hz or the entire frequency range with the exclusion of typical cardiac and respiratory frequency values tended to provide the best functional connectivity maps. Comparison with existing methods We found that the SMS-acquired rs-fMRI scans had improved the signal-noise separation, while preserving the same level of test-retest reliability compared to conventional EPI, and enabled the detection of reliable functional connectivity networks with scan times as short as 3 min. Conclusions Our findings suggest that whole-brain rs-fMRI studies may benefit from the increased temporal resolution enabled by the SMS-EPI acquisition, leading to drastic scan time reductions, which in turn should enable the more widespread use of rs-fMRI in clinical research protocols. [ABSTRACT FROM AUTHOR]

Purpose: Synchrotron microbeam radiation therapy (MRT) is an innovative irradiation modality based on spatial fractionation of a high-dose X-ray beam into lattices of microbeams. The increase in lifespan of brain tumor-bearing rats is associated with vascular damage but the physiological consequences of MRT on blood vessels have not been described. In this manuscript, we evaluate the oxygenation changes induced by MRT in an intracerebral 9L gliosarcoma model. Methods: Tissue responses to MRT (two orthogonal arrays (2×400Gy)) were studied using magnetic resonance-based measurements of local blood oxygen saturation (MR_SO2) and quantitative immunohistology of RECA-1, Type-IV collagen and GLUT-1, marker of hypoxia. Results: In tumors, MR_SO2 decreased by a factor of 2 in tumor between day 8 and day 45 after MRT. This correlated with tumor vascular remodeling, i.e. decrease in vessel density, increases in half-vessel distances (×5) and GLUT-1 immunoreactivity. Conversely, MRT did not change normal brain MR_SO2, although vessel inter-distances increased slightly. Conclusion: We provide new evidence for the differential effect of MRT on tumor vasculature, an effect that leads to tumor hypoxia. As hypothesized formerly, the vasculature of the normal brain exposed to MRT remains sufficiently perfused to prevent any hypoxia. [ABSTRACT FROM AUTHOR]

The PROMUS Element Plus US Post-Approval Study (PE-Plus PAS) was a prospective, open-label, multicenter, observational study designed to examine outcomes in everyday clinical practice in patients treated with everolimus-eluting, platinum-chromium PROMUS Element Plus stents at 52 centers in the United States. This is the first report of results from this large study. The primary end point of the PE-Plus PAS was 12-month cardiac death or myocardial infarction in the more restricted population of "PLATINUM-like" patients pooled from the PE-Plus PAS, PE-PROVE (PROMUS Element European post-approval study), and PLATINUM Workhorse/Small Vessel trials. Additional clinical end points were tested in the overall PE-Plus PAS patient population. Of the 2,683 patients enrolled in PE-Plus PAS, 70% were men, mean age was 64 years, 33% had diabetes, and 29% were "PLATINUM-like." Among the PLATINUM-like patients, 12-month cardiac death or myocardial infarction was 1.8% (33 of 1,855) with an upper 1-sided 95% confidence interval of 2.3%, which was significantly less than the prespecified performance goal of 3.2% (pnoninferiority <0.001). In the overall PE-Plus population, 12-month target vessel failure (defined as death, MI, or revascularization related to the target vessel) was 6.7% (170 of 2,554), cardiac death was 1.4% (37 of 2,554), MI was 1.1% (28 of 2,554), and ARC-definite/probable stent thrombosis was 0.7% (19 of 2,554). A prespecified secondary end point of 12-month target vessel failure in diabetic patients demonstrated a rate of 4.2% (14 of 332) with an upper 1-sided 95% confidence interval of 6.03%, which was significantly less than the performance goal of 12.6% (pnoninferiority <0.001). In conclusion, in this large registry of unselected patients, coronary artery revascularization with the PROMUS Element Plus everolimus-eluting stent demonstrates favorable results with low 1-year clinical event rates. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the regulation of glucose uptake in cells that participate in atherogenesis by stimuli relevant to this process, to gain mechanistic insight into the origin of the (18)fluorine-labeled 2-deoxy-D-glucose (FdG) uptake signals observed clinically. Background: Patient studies suggest that positron emission tomography (PET) using FdG can detect "active" atherosclerotic plaques, yet the mechanism giving rise to FdG signals remains unknown. Methods: We exposed cells to conditions thought to operate in atheroma and determined rates of glucose uptake. Results: Hypoxia, but not pro-inflammatory cytokines, potently stimulated glucose uptake in human macrophages and foam cells. Statins attenuated this process in vitro, suggesting that these agents have a direct effect on human macrophages. Immunohistochemical study of human plaques revealed abundant expression of proteins regulating glucose utilization, predominantly in macrophage-rich regions of the plaques-regions previously proved hypoxic. Smooth-muscle cells and endothelial cells markedly increased rates of glucose uptake when exposed to pro-inflammatory cytokines. Conclusions: Glucose uptake and, probably, FdG uptake signals in atheroma may reflect hypoxia-stimulated macrophages rather than mere inflammatory burden. Cytokine-activated smooth-muscle cells also may contribute to the FdG signal. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the regulation of glucose uptake in cells that participate in atherogenesis by stimuli relevant to this process, to gain mechanistic insight into the origin of the 18fluorine-labeled 2-deoxy-D-glucose (FdG) uptake signals observed clinically. Background: Patient studies suggest that positron emission tomography (PET) using FdG can detect “active” atherosclerotic plaques, yet the mechanism giving rise to FdG signals remains unknown. Methods: We exposed cells to conditions thought to operate in atheroma and determined rates of glucose uptake. Results: Hypoxia, but not pro-inflammatory cytokines, potently stimulated glucose uptake in human macrophages and foam cells. Statins attenuated this process in vitro, suggesting that these agents have a direct effect on human macrophages. Immunohistochemical study of human plaques revealed abundant expression of proteins regulating glucose utilization, predominantly in macrophage-rich regions of the plaques—regions previously proved hypoxic. Smooth-muscle cells and endothelial cells markedly increased rates of glucose uptake when exposed to pro-inflammatory cytokines. Conclusions: Glucose uptake and, probably, FdG uptake signals in atheroma may reflect hypoxia-stimulated macrophages rather than mere inflammatory burden. Cytokine-activated smooth-muscle cells also may contribute to the FdG signal. [ABSTRACT FROM AUTHOR]

• High coercivity is required only at the magnet's edges in wind turbine generators. • Several NdFeB materials with distinct properties can be arranged in a single magnet. • Conventional and SPS sintering are viable for preparation of multicomponent magnets. • Nonuniform distribution of magnetization is favorable for the target applications. Magnetic remanence (B r) and coercivity (H c) of hard magnets play a crucial role in electro-mechanical devices like electrical motors or generators. Elevated remanence ensures high efficiency of the device, and large coercivity protects the magnet from demagnetization. Usually, the increase of one comes at the cost of the other, such that the material optimization has a trade-off character. In this work, we demonstrate that in many electrical machines which use permanent magnets, high coercivity is required mainly at the edges of the magnet. This enables us to design a novel form of a permanent magnet, called a multicomponent magnet, where the sides of the magnet have high coercivity, while the central part is characterized by high remanence. Such multicomponent magnets are realized by two independent methods, namely, conventional high-temperature sintering and Spark Plasma Sintering (SPS). The magnetic and mechanical performances are suitable for applications, and simulation results using the magnetic characteristics of the multicomponent geometry predict its benefit on the device functionality. Further tuning of the geometry of the multicomponent permanent magnets opens avenues for promising applications, particularly in electrical motors for electrical vehicles. [ABSTRACT FROM AUTHOR]