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BACKGROUND AND AIMS: Myocardial perfusion imaging (MPI) and anatomical imaging with coronary computed tomography angiography (CCTA) can play an important role in the preprocedural planning of a chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We aimed to establish the feasibility of a novel dynamic computed tomography perfusion (CTP) analysis for the assessment of myocardial perfusion before and after a successful recanalization of CTO in patients undergoing CCTA as part of a standard preprocedural workup. METHODS: In a prospective observational study symptomatic patients underwent dynamic CTP on a dual-source CT scanner both before and 3 months after successful CTO PCI. RESULTS: Twenty-seven patients completed the study (63 ± 8 years old, 78% male). Following successful CTO PCI, there was a significant reduction in the ischemic burden (5 [5-7] versus 1 [0-2] segments, p < 0.001), and improvement in myocardial blood flow (85.3 [71.7-94.1] versus 134.6 [123.8-156.9] mL/min, p < 0.001) resulting in an increase in the relative flow reserve (0.49 [0.41-0.57] versus 0.88 [0.74-0.95], p < 0.001). CONCLUSIONS: CTP emerges as a robust and safe method for MPI in CTO patients. The single imaging session assessment of both coronary anatomy and perfusion with CT lends itself to precise disease phenotyping in the challenging population of CTO patients.
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Oclusión Coronaria , Imagen de Perfusión Miocárdica , Intervención Coronaria Percutánea , Enfermedades Vasculares , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Angiografía Coronaria/métodos , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos X , Angiografía por Tomografía Computarizada , Oclusión Coronaria/diagnóstico por imagen , Oclusión Coronaria/cirugía , Enfermedad Crónica , Imagen de Perfusión Miocárdica/métodos , Resultado del TratamientoRESUMEN
BACKGROUND: The Current European Society of Cardiology guidelines indicate specific target low-density lipoprotein cholesterol (LDL-C) levels for different cardiovascular risk categories in terms of prevention. However, the target for high-density lipoprotein cholesterol (HDL-C) and triglycerides has not been established. AIM: The study aims to investigate the associations betweenHDL-C,triglycerides, andcoronary plaque characteristics. METHODS: This was a prospective single-center study with enrolled consecutive patients with newly diagnosed significant (≥1stenosis ≥50%) CAD on computed tomography coronary angiography (CTCA). Patients had lipids andCTCA analysis, including high-risk plaque (HRP) features: low-attenuation plaque (LAP), napkin-ring sign (NRS), positive remodeling (PR), and spotty calcium (SC), type of the plaque (calcified, noncalcified, mixed), and their composition (calcified, fibrous, fibro-fatty, necrotic core). RESULTS: The study included 300 patients (191 men, 66 [8] years). Sixty-six percent of them had lipid-lowering therapy. HRPwas found in 208 patients. There was no association between LDL-C, plaque composition, and HRP presence. There was a negative correlation between HDL-C, fibro-fatty and necrotic core plaque components (P = 0.0002, P = 0.0009). There was a positive correlation between triglycerides and necrotic core (P = 0.038). There were differences in HDL-C and triglycerides in patients with and without NRS (47 vs. 53 mg/dl, P = 0.0002 and 128 vs. 109 mg/dl, P = 0.02). In logistic regression, HDL-C (odds ratio [OR], 0.95;95% confidence interval [CI], 0.93-0.98; P <0.001), triglycerides (OR, 1.00; 95% CI, 1.00-1.01; P = 0.02), and male sex (OR, 3.04; 95% CI, 1.41-6.52; P = 0.004) were NRS predictors. In multivariable regression, only HDL-C (OR, 0.96; 95% CI, 0.93-0.99; P = 0.02) was an independent predictor of NRS. CONCLUSION: Lower HDL-C and higher triglycerides were associated with NRS presence and more necrotic core plaque components in coronary plaques in patients with newly diagnosed CAD.
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Enfermedad de la Arteria Coronaria , Placa Aterosclerótica , Humanos , Masculino , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Angiografía Coronaria/métodos , Triglicéridos , HDL-Colesterol , Estudios Prospectivos , LDL-Colesterol , Placa Aterosclerótica/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Factores de RiesgoRESUMEN
ackground: The extent of myocardial ischemia is the crucial prognostic factor for interventional treatment decision making for coronary artery disease. The ability of computed tomography per-fusion (CTP) to provide the missing volumetric information and its clinical value remains unknown. AIMS: The study aimed to compare a novel ischemic volume quantification method based on dynamic computed tomography perfusion (VOL CTP) with other CT-based imaging modalities for revascularization prediction. METHODS: In this prospective study, 53 (25 females, 63.5 [8.5] years old) consecutive symptomatic patients with 50%-90% coronary artery stenosis (n ≥1) on coronary computed tomography angiography underwent computed-tomography-derived fractional flow reserve (CT-FFR) analysis and dynamic CTP. We calculated the percentage of myocardial ischemia on the CTP-derived images. A 10% cut-off was used to define functionally significant ischemia. The outcomes include coronary revas-cularization during the follow-up of 2.5 (interquartile range, 1.4-2.8) years. Physicians were blinded to the results of CTP and CT-FFR. RESULTS: Of the 53 patients in the study (68 arteries with 50%-90% stenosis), 16 underwent revascularization (12 elective, 4 event-driven). In the CTP quantitative analysis, 26 patients had ischemia. Overall, 18 patients had ischemia ≥10% on volumetric ischemia quantification based on dynamic computed tomography perfusion (VOL CTP), and 28 patients had CT-FFR <0.8. VOL CTP, standard CTP, CT-FFR, and computed tomography coronary angiography (CTA) ≥70% performed well for the prediction of total revascularization. Area under the curve was 0.973 vs. 0.865, vs. 0.793, vs. 0.668, respectively. The VOL CTP with ≥10% cut-off was superior to the CT-FFR, standard CTP, and CTA ≥70% (P <0.001; P = 0.002 and P <0.001 respectively). CONCLUSIONS: VOL CTP quantification is feasible and adds important, actionable information to that provided by standard CTP or CT-FFR in patients with 50%-90% coronary artery stenosis.
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Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Imagen de Perfusión Miocárdica , Niño , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Femenino , Humanos , Imagen de Perfusión Miocárdica/métodos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tomografía Computarizada por Rayos X/métodosRESUMEN
BACKGROUND: The CAT-CAD trial showed that coronary computed tomography angiography (CTA) in patients with a high prevalence of coronary artery disease (CAD) and indications for invasive coronary angiography (ICA) reduces the number of patients undergoing ICA by two-thirds and nearly eradicates non-actionable ICAs. However, the long-term benefits of this non-invasive strategy remain unknown. AIMS: To evaluate the long-term efficacy and safety of a non-invasive strategy employing coronary CTA vs. ICA as the first-line imaging test in stable patients with a high clinical likelihood of obstruc-tive CAD. METHODS: The long-term outcomes were evaluated for 36 months following randomization and included the efficacy outcome (analyzed as the composite of major adverse cardiovascular events (MACE): all-cause death, acute coronary syndrome, unplanned coronary revascularization, urgent hospitalization for a cardiovascular reason, a stroke) and the safety outcome (analyzed as a cumulative incidence of serious adverse events). RESULTS: One hundred and twenty participants at a mean age of 60.6 (7.9) years (female, 35.0%) were randomized with an allocation ratio of 1:1 to coronary CTA and direct ICA as the first-line anatomical test for suspected obstructive CAD. There were no significant differences between both diagnostic strategies neither in terms of the long-term efficacy (MACE occurrence: 15.5% in coronary CTA group vs. 16.7% in ICA group; log-rank P = 0.89) nor the long-term safety (cumulative number of serious adverse events: 36 vs. 38; P = 0.79, respectively). CONCLUSIONS: Long-term follow-up of the randomized CAT-CAD trial confirms that the strategy employing coronary CTA is an effective and safe, non-invasive, outpatient-based alternative to ICA for patients with a high clinical likelihood of obstructive CAD.
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Síndrome Coronario Agudo , Enfermedad de la Arteria Coronaria , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/efectos adversos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Femenino , Humanos , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos XRESUMEN
We aimed to establish the feasibility and safety of dynamic computed tomography perfusion (CTP) in patients with chronic total occlusion (CTO) undergoing percutaneous coronary intervention (PCI). Ten consecutive CTO patients with preserved left ventricular ejection fraction (≥50%) underwent regadenoson dynamic CTP prior to and at least 3 months after successful CTO recanalization. Quantitative absolute and indexed values of stress myocardial blood flow (MBF) were measured for each myocardial segment, and perfusion defect size was defined by the number of segments with indexed MBF ≤0.78. The control group comprised 10 subjects without ischemia on CTP. Out of 20 CTP studies with 320 segments, 311 segments (97.2%) were interpretable. The dose-length product for CTP was 589.5 â± â144.3 mGy cm, and no severe adverse reactions to either regadenoson or contrast were observed. Successful PCI resulted in a significant increase in stress MBF in CTO (101.8 [82.9-127.1] vs. 158.4 [132.6-172] ml/100ml/min, p â= â0.004). Overall, there were significant reductions in both CTO and total defect size post-PCI (5 [5-6] vs. 1 [0.3-2] and 6 [5-8.5] vs. 1.5 [1-3.8] segments, both p â= â0.002). In segment analysis, the indexed MBF was lowest in the pre-PCI CTO group (0.90 [0.53-1.0]), followed by post-PCI CTO group (0.96 [0.88-1.0]) and the control group (0.98 [0.94-1.0]). Dynamic CTP is feasible and safe, and shows large perfusion defects in patients with CTO. While ischemic burden can be significantly improved after successful CTO PCI, it is still larger as compared with normal myocardium. NCT04465526: The Influence of Coronary Chronic Total Occlusion on Myocardial Perfusion on Computed Tomography (COPACABANA).
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Oclusión Coronaria , Imagen de Perfusión Miocárdica , Intervención Coronaria Percutánea , Tomografía Computarizada por Rayos X , Humanos , Enfermedad Crónica , Angiografía Coronaria , Circulación Coronaria/fisiología , Oclusión Coronaria/diagnóstico por imagen , Oclusión Coronaria/terapia , Estudios de Factibilidad , Imagen de Perfusión Miocárdica/efectos adversos , Imagen de Perfusión Miocárdica/métodos , Valor Predictivo de las Pruebas , Volumen Sistólico , Tomografía Computarizada por Rayos X/efectos adversos , Resultado del Tratamiento , Función Ventricular IzquierdaAsunto(s)
Trasplante de Corazón , Isquemia Miocárdica , Imagen de Perfusión Miocárdica , Aloinjertos , Rechazo de Injerto/diagnóstico por imagen , Trasplante de Corazón/efectos adversos , Humanos , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/etiología , Imagen de Perfusión Miocárdica/métodos , Imagen de Perfusión , TomografíaRESUMEN
BACKGROUND: Catecholamines are recommended as first-line drugs to treat hemodynamic instability after out-of-hospital cardiac arrest (OHCA). The benefit-to-risk ratio of catecholamines is dose dependent, however, their effect on metabolism and organ function early after OHCA has not been investigated. METHODS: The Post-Cardiac Arrest Syndrome (PCAS) pilot study was a prospective, observational, multicenter study. The primary outcomes of this analysis were association between norepinephrine/cumulative catecholamines doses and neuron specific enolase (NSE)/lactate concentration over the first 72 hours after resuscitation. The association was adjusted for proven OHCA mortality predictors and verified with propensity score matching (PSM). RESULTS: Overall 148 consecutive OHCA patients; aged 18-91 (62.9 ± 15.27), 41 (27.7%) being female, were included. Increasing norepinephrine and cumulative catecholamines doses were significantly associated with higher NSE concentration on admission (r = 0.477, p < 0.001; r = 0.418, p < 0.001) and at 24 hours after OHCA (r = 0.339, p < 0.01; r = 0.441, p < 0.001) as well as with higher lactate concentration on admission (r = 0.404, p < 0.001; r = 0.280, p < 0.01), at 24 hours (r = 0.476, p < 0.00; r = 0.487, p < 0.001) and 48 hours (r = 0.433, p < 0.01; r = 0.318, p = 0.01) after OHCA. The associations remained significant up to 48 hours in non-survivors after PSM. CONCLUSIONS: Increasing the dose of catecholamines is associated with higher lactate and NSE concentration, which may suggest their importance for tissue oxygen delivery, anaerobic metabolism, and organ function early after OHCA.
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Doping and modification of TiO2 nanotubes were carried out using the hydrothermal method. The introduction of small amounts of cobalt (0.1 at %) into the structure of anatase caused an increase in the absorption of light in the visible spectrum, changes in the position of the flat band potential, a decrease in the threshold potential of water oxidation in the dark, and a significant increase in the anode photocurrent. The material was characterized by the SEM, EDX, and XRD methods, Raman spectroscopy, XPS, and UV-Vis reflectance measurements. Electrochemical measurement was used along with a number of electrochemical methods: chronoamperometry, electrochemical impedance spectroscopy, cyclic voltammetry, and linear sweep voltammetry in dark conditions and under solar light illumination. Improved photoelectrocatalytic activity of cobalt-doped TiO2 nanotubes is achieved mainly due to its regular nanostructure and real surface area increase, as well as improved visible light absorption for an appropriate dopant concentration.
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Cardiovascular disease is a model example of a preventable condition for which practice guidelines are particularly important. In 2016, the joint task force created by the European Society of Cardiology (ESC) together with 10 other societies released the new version of the European guidelines on cardiovascular disease prevention. To facilitate the implementation of the ESC guidelines, a dedicated prevention implementation committee has been established within the European Association of Preventive Cardiology. The paper will first explore potential barriers to the guidelines' implementation. It then develops a discussion that seeks to inform the future development of the committee's work, including a new definition of the guidelines' stakeholders (health policy-makers, healthcare professionals and health educators, patient organisations, entrepreneurs and the general public), future activities within four specific areas: strengthening awareness of the guidelines among stakeholders; supporting organisational changes to facilitate the guidelines' implementation; motivating stakeholders to utilise the guidelines; and present ideas on new implementation strategies. Providing multifaceted cooperation between healthcare professionals, healthcare management executives and health policy-makers, the novel approach proposed in this paper should contribute to a wider use of the 2016 ESC guidelines and produce desired effects of less cardiovascular disease morbidity and mortality. Furthermore, the solutions presented within the paper may constitute a benchmark for the implementation of practice guidelines in other medical disciplines.
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In this study, we present a novel strategy for enhancing polyaniline stability and thus obtaining an electrode material with practical application in supercapacitors. A promising (graphite foil/polyaniline/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) GF/PANI/PEDOT:PSS) electrode material was characterized and used in the construction of a symmetric supercapacitor that provides an outstanding high power density. For this purpose, the electropolymerization of PANI was carried out on a graphite foil and then a thin protective layer of PEDOT:PSS was deposited. The presence of the nanometer PEDOT:PSS layer made it possible to widen the electroactivity potential range of the electrode material. Moreover, the synergy between materials positively affected the amount of accumulated charge, and thus the thin PEDOT:PSS layer contributed to enhancing the specific capacity of the electrode material. The electrochemical performance of the GF/PANI/PEDOT:PSS electrode, as well as the symmetrical supercapacitor, was investigated by cyclic voltammetry and galvanostatic charge/discharge cycles in 1 M H2SO4 at room temperature. The fabricated electrode material shows a high specific capacitance (Csp) of 557.4 Fg-1 and areal capacitance (Careal) of 2600 mF·cm-2 in 1 M H2SO4 at a current density of 200 mA·cm-2 (~4 A·g-1). The supercapacitor performance was studied and the results show that a thin PEDOT:PSS layer enables cycling stability improvement of the device from 54% to 67% after 10,000 cycles, and provides a high specific capacity (159.8 F·g-1) and a maximum specific power (18,043 W·kg-1) for practical applications.
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BACKGROUND: The use of regadenoson in dynamic computed tomography perfusion (CTP) and magnetic resonance myocardial perfusion imaging (MR MPI) is offlabel. AIMS: The study aimed to assess the safety of regadenoson with theophylline reversal during CTP and MR MPI in patients with coronary artery disease (CAD). METHODS: In this prospective study, patients with 1 or more intermediate coronary artery stenoses on computed tomography angiography underwent CTP and MR MPI with 0.4 mg of regadenoson. After examinations, 200 mg of theophylline was given intravenously in 100 ml of saline. Changes in blood pressure (BP) and heart rate (HR) were repeatedly assessed. All side effects and adverse events were recorded. RESULTS: Out of 106 examinations in 53 patients (25 females, 63.5 [8.5] years), all were diagnostic. There were no deaths, myocardial infarctions, severe arrhythmias, highgrade atrioventricular blocks, or bronchospasms. The most common symptoms were palpitations (17%), hot flushing (8%), chest discomfort (4%), and mild dyspnea (3%). There were no differences between baseline and peak BP. There was an increase in median (interquartile range) peak HR after regadenoson as compared with baseline (MR MPI, 63 [59-75] bpm vs 93 [86-102] bpm; P <0.001; and CTP, 65 [60-70] bpm vs 95 [86-107] bpm; P <0.001). The hemodynamic response to regadenoson and its side effects were completely reversible by theophylline. CONCLUSIONS: Regadenoson may be a safe vasodilator for CTP and MR MPI in patients with CAD. The administration of theophylline after perfusion is safe and reverses side effects of regadenoson.
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Enfermedad de la Arteria Coronaria , Imagen de Perfusión Miocárdica , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Perfusión , Estudios Prospectivos , Purinas , Pirazoles , Teofilina/efectos adversos , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
The biomass of one type cultivated diatoms (Pseudostaurosira trainorii), being a source of 3D-stuctured biosilica and organic matter-the source of carbon, was thermally processed to become an electroactive material in a potential range adequate to become an anode in lithium ion batteries. Carbonized material was characterized by means of selected solid-state physics techniques (XRD, Raman, TGA). It was shown that the pyrolysis temperature (600 °C, 800 °C, 1000 °C) affected structural and electrochemical properties of the electrode material. Biomass carbonized at 600 °C exhibited the best electrochemical properties reaching a specific discharge capacity of 460 mAh g-1 for the 70th cycle. Such a value indicates the possibility of usage of biosilica as an electrode material in energy storage applications.
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Rechazo de Injerto/diagnóstico por imagen , Trasplante de Corazón/efectos adversos , Imagen de Perfusión Miocárdica , Tomografía Computarizada por Rayos X , Adulto , Biopsia , Estudios de Casos y Controles , Estudios de Factibilidad , Femenino , Rechazo de Injerto/etiología , Rechazo de Injerto/patología , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Valor Predictivo de las Pruebas , Vasodilatadores/administración & dosificaciónRESUMEN
BACKGROUND: Although the lungs are potentially highly susceptible to post-cardiac arrest syndrome injury, the issue of acute respiratory failure after out-of-hospital cardiac arrest has not been investigated. The objectives of this analysis were to determine the prevalence of acute respiratory failure after out-of-hospital cardiac arrest, its association with post-cardiac arrest syndrome inflammatory response and to clarify its importance for early mortality. METHODS: The Post-Cardiac Arrest Syndrome (PCAS) pilot study was a prospective, observational, six-centre project (Poland 2, Denmark 1, Spain 1, Italy 1, UK 1), studying patients resuscitated after out-of-hospital cardiac arrest of cardiac origin. Primary outcomes were: (a) the profile of organ failure within the first 72 hours after out-of-hospital cardiac arrest; (b) in-hospital and short-term mortality, up to 30 days of follow-up. Respiratory failure was defined using a modified version of the Berlin acute respiratory distress syndrome definition. Inflammatory response was defined using leukocytes (white blood cells), platelet count and C-reactive protein concentration. All parameters were assessed every 24 hours, from admission until 72 hours of stay. RESULTS: Overall, 148 patients (age 62.9±15.27 years; 27.7% women) were included. Acute respiratory failure was noted in between 50 (33.8%) and 75 (50.7%) patients over the first 72 hours. In-hospital and short-term mortality was 68 (46.9%) and 72 (48.6%), respectively. Inflammation was significantly associated with the risk of acute respiratory failure, with the highest cumulative odds ratio of 748 at 72 hours (C-reactive protein 1.035 (1.001-1.070); 0.043, white blood cells 1.086 (1.039-1.136); 0.001, platelets 1.004 (1.001-1.007); <0.005). Early acute respiratory failure was related to in-hospital mortality (3.172, 95% confidence interval 1.496-6.725; 0.002) and to short-term mortality (3.335 (1.815-6.129); 0.0001). CONCLUSIONS: An inflammatory response is significantly associated with acute respiratory failure early after out-of-hospital cardiac arrest. Acute respiratory failure is associated with a worse early prognosis after out-of-hospital cardiac arrest.
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Hipotermia Inducida/métodos , Inflamación/etiología , Unidades de Cuidados Intensivos/estadística & datos numéricos , Paro Cardíaco Extrahospitalario/terapia , Síndrome de Paro Post-Cardíaco/complicaciones , Insuficiencia Respiratoria/etiología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria/tendencias , Humanos , Incidencia , Inflamación/epidemiología , Masculino , Persona de Mediana Edad , Paro Cardíaco Extrahospitalario/complicaciones , Proyectos Piloto , Síndrome de Paro Post-Cardíaco/mortalidad , Estudios Prospectivos , Insuficiencia Respiratoria/epidemiología , Tasa de Supervivencia/tendencias , Adulto JovenRESUMEN
BACKGROUND: The purpose of this study was to assess the feasibility of low-dose dynamic regadenoson computed tomography perfusion (CTP) protocol, and to determine which parameters provide the best diagnostic yield for the presence and burden of ischemia in reference to the magnetic resonance myocardial perfusion imaging (MR MPI). METHODS: Fifty six patients with ≥1 intermediate (50-90%) coronary artery stenosis on CTA underwent dynamic stress CTP and MR MPI. The distribution of contrast agent in CTP was represented for each myocardial segment as either absolute or indexed: myocardial blood flow (MBF), myocardial blood volume (MBV), perfused capillary blood volume (PCBV), peak value (PV), time to peak (TTP), respectively. RESULTS: Of 56 patients (25 females, 63.5 ± 8.5y), 15 (27%) were diagnosed with reversible ischemia and 3 (5%) with fixed ischemia on the MR MPI. The median radiation dose for dynamic CTP scan was 352.00 [276.4-496.6] mGy*cm. The optimal cut-off point for the prediction of reversible ischemia on MR MPI for the absolute parameters were: MBF ≤156.49 (AUC=0.899), MBV ≤15.06 (AUC=0.901), PCBV ≤7.90 (AUC=0.880), PV ≤ 88.30 (AUC=0.766), TTP ≥22.58 (AUC=0.595); and for the indexed: indexed MBF ≤0.78 (AUC=0.926), indexed MBV ≤0.81 (AUC=0.924), indexed PCBV ≤0.70 (AUC=0.894); indexed PV ≤ 0.79 (AUC=0.869), indexed TTP ≤0.87 (AUC=0.685). The best parameters for ischemia detection were indexed MBF and indexed MBV, with sensitivities 91% and 89%, specificities 97% and 96%, NPV 99% and 99%, PPV 76% and 69%, and accuracies 96% and 95%, respectively. In per patient analysis, indexed MBF correlated significantly better with the ischemia burden than any of the absolute parameters (p < 0.01 for all comparisons). CONCLUSIONS: Regadenoson dynamic CTP using low-dose protocol is feasible while maintaining high diagnostic accuracy. The best diagnostic value may be provided by indexed parameters, of which indexed MBF and indexed MBV may provide best incremental value in identification of the presence and burden of ischemia.
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Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Circulación Coronaria , Estenosis Coronaria/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Purinas/administración & dosificación , Pirazoles/administración & dosificación , Vasodilatadores/administración & dosificación , Anciano , Velocidad del Flujo Sanguíneo , Enfermedad de la Arteria Coronaria/fisiopatología , Estenosis Coronaria/fisiopatología , Estudios de Factibilidad , Femenino , Humanos , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Dosis de Radiación , Reproducibilidad de los Resultados , Índice de Severidad de la EnfermedadRESUMEN
Studying the effect of high pressure (exceeding 10 kbar) on the structure of solids allows us to gain deeper insight into the mechanism governing crystal structure stability. Here, we report a study on the high-pressure behavior of zinc difluoride (ZnF2)-an archetypical ionic compound which at ambient pressure adopts the rutile (TiO2) structure. Previous investigations, limited to a pressure of 15 GPa, revealed that this compound undergoes two pressure-induced phase transitions, i.e., TiO2 â CaCl2 at 4.5 GPa and CaCl2 â HP-PdF2 at 10 GPa. Within this joint experimental-theoretical study, we extend the room-temperature phase diagram of ZnF2 up to 55 GPa. By means of Raman spectroscopy measurements we identify two new phase transitions, HP-PdF2 â HP1-AgF2 at 30 GPa and HP1-AgF2 â PbCl2 at 44 GPa. These results are confirmed by density functional theory calculations which indicate that in the HP1-AgF2 polymorph the coordination sphere of Zn2+ undergoes drastic changes upon compression. Our results point to important differences in the high-pressure behavior of ZnF2 and MgF2, despite the fact that both compounds contain cations of similar size. We also argue that the HP1-AgF2 structure, previously observed only for AgF2, might be observed at large compression in other AB2 compounds.
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This paper provides an update on the European Society of Cardiology task force report on the management of chest pain. Its main purpose is to provide an update on the decision algorithms and diagnostic pathways to be used in the emergency department for the assessment and triage of patients with chest pain symptoms suggestive of acute coronary syndromes.
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Síndrome Coronario Agudo/diagnóstico , Dolor en el Pecho/diagnóstico , Infarto del Miocardio/diagnóstico , Infarto del Miocardio con Elevación del ST/diagnóstico , Síndrome Coronario Agudo/epidemiología , Enfermedad Aguda , Algoritmos , Biomarcadores/metabolismo , Cardiología , Dolor en el Pecho/epidemiología , Toma de Decisiones , Servicio de Urgencia en Hospital/estadística & datos numéricos , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Manejo de Atención al Paciente/normas , Intervención Coronaria Percutánea/métodos , Medición de Riesgo , Infarto del Miocardio con Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/cirugía , Sociedades Médicas/organización & administración , Triaje , Troponina/sangreRESUMEN
Composites based on the titania nanotubes were tested in aqueous electrolyte as a potential electrode material for energy storage devices. The nanotubular morphology of TiO2 was obtained by Ti anodization. TiO2 nanotubes were covered by a thin layer of bismuth vanadate using pulsed laser deposition. The formation of the TiO2/BiVO4 junction leads to enhancement of pseudocapacitance in the cathodic potential range. The third component, the conjugated polymer PEDOT:PSS, was electrodeposited from an electrolyte containing the monomer EDOT and NaPSS as a source of counter ions. Each stage of modification and deposition affected the overall capacitance and allowed for an expansion of the potential range of electroactivity. Multiple charge/discharge cycles were performed to characterize the electrochemical stability of the inorganic-organic hybrid electrode. Capacitance values higher than 10 mF·cm-2 were maintained even after 10000 galvanostatic cycles (i c = i a = 0.5 mA·cm-2).