A practical clinical score

Copyright © 2022 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.INTRODUCTION AND OBJECTIVES: Obstructive coronary artery disease (CAD) remains the most common etiology of heart failure with reduced ejection fraction (HFrEF). However, there is controversy whether invasive coronary angiography (ICA) should be used initially to exclude CAD in patients presenting with new-onset HFrEF of unknown etiology. Our study aimed to develop a clinical score to quantify the risk of obstructive CAD in these patients. METHODS: We performed a cross-sectional observational study of 452 consecutive patients presenting with new-onset HFrEF of unknown etiology undergoing elective ICA in one academic center, between January 2005 and December 2019. Independent predictors for obstructive CAD were identified. A risk score was developed using multivariate logistic regression of designated variables. The accuracy and discriminative power of the predictive model were assessed. RESULTS: A total of 109 patients (24.1%) presented obstructive CAD. Six independent predictors were identified and included in the score: male gender (2 points), diabetes (1 point), dyslipidemia (1 point), smoking (1 point), peripheral arterial disease (1 point), and regional wall motion abnormalities (3 points). Patients with a score ≤3 had less than 15% predicted probability of obstructive CAD. Our score showed good discriminative power (C-statistic 0.872; 95% CI 0.834-0.909: p<0.001) and calibration (p=0.333 from the goodness-of-fit test). CONCLUSIONS: A simple clinical score showed the ability to predict the risk of obstructive CAD in patients presenting with new-onset HFrEF of unknown etiology and may guide the clinician in selecting the most appropriate diagnostic modality for the assessment of obstructive CAD.proofepub_ahead_of_prin

Coronary computed tomography angiography-adapted Leaman score as a tool to noninvasively quantify total coronary atherosclerotic burden

To describe a coronary computed tomography angiography (CCTA)-adapted Leaman score (CT-LeSc) as a tool to quantify total coronary atherosclerotic burden with information regarding localization, type of plaque and degree of stenosis and to identify clinical predictors of a high coronary atherosclerotic burden as assessed by the CT-LeSc. Single center prospective registry including a total of 772 consecutive patients undergoing CCTA (Dual-source CT) from April 2011 to March 2012. For the purpose of this study, 581 stable patients referred for suspected coronary artery disease (CAD) without previous myocardial infarction or revascularization procedures were included. Pre-test CAD probability was determined using both the Diamond-Forrester extended CAD consortium method (DF-CAD consortium model) and the Morise score. Cardiovascular risk was assessed with the HeartScore. The cut-off for the 3rd tercile (CT-LeSc ≥8.3) was used to define a population with a high coronary atherosclerotic burden. The median CT-LeSc in this population (n = 581, 8,136 coronary segments evaluated; mean age 57.6 ± 11.1; 55.8 % males; 14.6 % with diabetes) was 2.2 (IQR 0-6.8). In patients with CAD (n = 341), the median CT-LeSc was 5.8 (IQR 3.2-9.6). Among patients with nonobstructive CAD, most were classified in the lowest terciles (T1, 43.0 %; T2, 36.1 %), but 20.9 % were in the highest tercile (T3). The majority of the patients with obstructive CAD were classified in T3 (78.2 %), but 21.8 % had a CT-LeSc in lower terciles (T1 or T2). The independent predictors of a high CT-LeSc were: Male sex (OR 1.73; 95 % CI 1.04-2.90) diabetes (OR 2.91; 95 % CI 1.61-5.23), hypertension (OR 2.54; 95 % CI 1.40-4.63), Morise score ≥16 (OR 1.97; 95 % CI 1.06-3.67) and HeartScore ≥5 (OR 2.42; 95 % CI 1.41-4.14). We described a cardiac CT adapted Leaman score as a tool to quantify total (obstructive and nonobstructive) coronary atherosclerotic burden, reflecting the comprehensive information about localization, degree of stenosis and type of plaque provided by CCTA. Male sex, hypertension, diabetes, a HeartScore ≥5 % and a Morise score ≥16 were associated with a high coronary atherosclerotic burden, as assessed by the CT-LeSc. About one fifth of the patients with nonobstructive CAD had a CT-LeSc in the highest tercile, and this could potentially lead to a reclass

Propriedades à flexão dos compósitos híbridos em placas enrugadas

The traditional carbon fibre-reinforced composites offer excellent mechanical properties while having a low density, which makes them an ideal solution for the applications where weight is a major concern. The self-reinforced composites (SRC’s) consist of polymer fibres reinforcing a matrix made from the same material. In fact, it is by partially melting the fibres that the matrix is created. This type of composites provide a high toughness but lack the high stiffness and strength needed in structural applications. Hybrid composites are a combination of at least two types of fibres in a matrix. By hybridizing self-reinforced polypropylene (SRPP) with unidirectional (UD) carbon fibre reinforced polypropylene (CFRPP), it is expected to combine properties of both composite types. The goal is to have a stiff and strong composite while maintaining a high toughness. This thesis aims to understand how the material properties of a hybrid composite influence the flexural properties in a corrugated plate. The flexural properties of hybrid composites have been studied but always in flat surfaces. Also, the low compressive properties of polymer fibres make it difficult to capture the flexural properties. By using this type of surface, the flexural properties should not be as highly dependent on the position of the carbon fibre (CF) laminae in relation to the neutral plane as they are for flat laminates. Experimental work has been performed to understand the dependence of the flexural properties of hybrid composite materials on the carbon fibre volume fraction (Vf) and position. The experimental work was supported by a numerical modelling study. This study established preliminary knowledge needed for further developments of the model. In combination with the experimental work, the limitations of the current model are pointed out. The achievement of a more advanced model in the future, that can predict the behaviour of these hybrid composite materials when subjected to bending, is possible. The main conclusions of this work were that the stiffness of a corrugated hybrid composite plate is not influenced by the position of the UD CFRPP layers. This property only changes with the CF Vf. The maximum flexural load and displacement at this point are also influenced by the CF content and by the thickness of the UD CFRPP layers. The other work we ever did together. Without the experience of working with him, there would be a lot of things I would not have learned. To Carlos Lavoura and José Canhola, my mentors in my rowing experience. They were the ones who guided me throughout ten years of rowing, making me a better athlete and a better person. For giving me the will to never give up on my goals and dreams, thank you.Os tradicionais materiais compósitos reforçados com fibras de carbono oferecem excelentes propriedades mecânicas enquanto mantêm uma baixa densidade, o que faz deles uma solução ideal para aplicações nas quais o peso é um fator a considerar. Os materiais compósitos auto-reforçados consistem em fibras poliméricas que reforçam uma matriz do mesmo material. De fato, é ao fundir parcialmente as fibras que se obtém a matriz. Este tipo de materiais compósitos proporciona uma elevada tenacidade mas não tem a alta rigidez e resistência mecânica necessária em aplicações estruturais. Os materiais compósitos híbridos resultam da combinação de dois tipos de fibras numa matriz. Ao hibridizar polipropileno auto-reforçado com polipropileno reforçado com fibras de carbono unidirecionais, é esperada a combinação das propriedades dos dois tipos de compósitos. O objetivo é que se tenha um compósito rígido e resistente enquanto se mantém uma alta tenacidade. Esta dissertação tem como objetivo a compreensão de como as propriedades materiais de um compósito híbrido influenciam as propriedades à flexão numa placa enrugada. As propriedades à flexão de compósitos híbridos já foram estudadas, mas sempre em superfícies planas. Além disso, as fracas propriedades compressivas das fibras poliméricas tornam difícil capturar as propriedades à flexão destas. Ao usar este tipo de superfície, as propriedades à flexão não deverão ser tão dependentes da posição das camadas de fibras de carbono em relação ao plano neutro como se verifica para laminados. O trabalho experimental foi realizado para entender a dependência das propriedades à flexão de um material compósito híbrido com a variação da fração volúmica e posição das fibras de carbono. O trabalho experimental foi suportado por um estudo de modelação numérica. Este estudo estabeleceu conhecimentos preliminares necessários para desenvolvimentos futuros do modelo. Em combinação com o trabalho experimental, as limitações do modelo atual são enunciadas. O desenvolvimento de um modelo mais avançado no futuro, que possa prever o comportamento destes materiais compósitos híbridos quando sujeitos a flexão, é possível. As principais conclusões deste trabalho são que a rigidez dos compósitos híbridos em placas enrugadas não é influenciada pela posição das camadas de fibras de carbono. Esta propriedade apenas varia com a fração volúmica de fibras de carbono. A carga de flexão máxima e deslocamento também são influenciados pelo conteúdo de fibras de carbono e pela espessura das camadas de fibras de carbono unidirecionais. O trabalho de modelação confirmou o comportamento da rigidez mas o modelo não é capaz de prever as outras propriedades. Ainda é possivel fazer um grande desenvolvimento do modelo

Direct comparison of the fibre break development in unidirectional carbon fibre composites under tension predicted by statistical models and measured using 4D in-situ SRCT

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State-of-the-art models for mechanical performance of carbon-glass hybrid composites in wind turbine blades

Wind turbine blades are a key growth market for fibre-hybrid composites, as they offer the potential for higher turbine efficiency at a reduced cost. This paper therefore overviews the developments of KU Leuven models for mechanical properties relevant to wind turbine blades, including fibre-hybridisation, size scaling effects, flexure, transverse cracking, stress relaxation and fatigue. The strengths and limitations of the models will be highlighted with a particular focus on relevance for wind turbine blades. While significant steps forward have been made, the various developments still need to be incorporated in one all-encompassing model, and further work is needed on gathering the required input data and detailed experimental validation studies.status: Published onlin

SARS-CoV-2 and Stroke Characteristics: A Report From the Multinational COVID-19 Stroke Study Group

International audienceBackground and Purpose: Stroke is reported as a consequence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in several reports. However, data are sparse regarding the details of these patients in a multinational and large scale. Methods: We conducted a multinational observational study on features of consecutive acute ischemic stroke, intracranial hemorrhage, and cerebral venous or sinus thrombosis among SARS-CoV-2–infected patients. We further investigated the risk of large vessel occlusion, stroke severity as measured by the National Institutes of Health Stroke Scale, and stroke subtype as measured by the TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria among patients with acute ischemic stroke. In addition, we explored the neuroimaging findings, features of patients who were asymptomatic for SARS-CoV-2 infection at stroke onset, and the impact of geographic regions and countries’ health expenditure on outcomes. Results: Among the 136 tertiary centers of 32 countries who participated in this study, 71 centers from 17 countries had at least 1 eligible stroke patient. Of 432 patients included, 323 (74.8%) had acute ischemic stroke, 91 (21.1%) intracranial hemorrhage, and 18 (4.2%) cerebral venous or sinus thrombosis. A total of 183 (42.4%) patients were women, 104 (24.1%) patients were <55 years of age, and 105 (24.4%) patients had no identifiable vascular risk factors. Among acute ischemic stroke patients, 44.5% (126 of 283 patients) had large vessel occlusion; 10% had small artery occlusion according to the TOAST criteria. We observed a lower median National Institutes of Health Stroke Scale (8 [3–17] versus 11 [5–17]; P =0.02) and higher rate of mechanical thrombectomy (12.4% versus 2%; P <0.001) in countries with middle-to-high health expenditure when compared with countries with lower health expenditure. Among 380 patients who had known interval onset of the SARS-CoV-2 and stroke, 144 (37.8%) were asymptomatic at the time of admission for SARS-CoV-2 infection. Conclusions: We observed a considerably higher rate of large vessel occlusions, a much lower rate of small vessel occlusion and lacunar infarction, and a considerable number of young stroke when compared with the population studies before the pandemic. The rate of mechanical thrombectomy was significantly lower in countries with lower health expenditures