1,721,017 research outputs found
Prediction of incident cardiovascular events using machine learning and CMR radiomics
No full textObjectives: evaluation of the feasibility of using cardiovascular magnetic resonance (CMR) radiomics in the prediction of incident atrial fibrillation (AF), heart failure (HF), myocardial infarction (MI), and stroke using machine learning techniques.Methods: we identified participants from the UK Biobank who experienced incident AF, HF, MI, or stroke during the continuous longitudinal follow-up. The CMR indices and the vascular risk factors (VRFs) as well as the CMR images were obtained for each participant. Three-segmented regions of interest (ROIs) were computed: right ventricle cavity, left ventricle (LV) cavity, and LV myocardium in end-systole and end-diastole phases. Radiomics features were extracted from the 3D volumes of the ROIs. Seven integrative models were built for each incident cardiovascular disease (CVD) as an outcome. Each model was built with VRF, CMR indices, and radiomics features and a combination of them. Support vector machine was used for classification. To assess the model performance, the accuracy, sensitivity, specificity, and AUC were reported.Results: AF prediction model using the VRF+CMR+Rad model (accuracy: 0.71, AUC 0.76) obtained the best result. However, the AUC was similar to the VRF+Rad model. HF showed the most significant improvement with the inclusion of CMR metrics (VRF+CMR+Rad: 0.79, AUC 0.84). Moreover, adding only the radiomics features to the VRF reached an almost similarly good performance (VRF+Rad: accuracy 0.77, AUC 0.83). Prediction models looking into incident MI and stroke reached slightly smaller improvement.Conclusions: radiomics features may provide incremental predictive value over VRF and CMR indices in the prediction of incident CVDs.Key points: • Prediction of incident atrial fibrillation, heart failure, stroke, and myocardial infarction using machine learning techniques. • CMR radiomics, vascular risk factors, and standard CMR indices will be considered in the machine learning models. • The experiments show that radiomics features can provide incremental predictive value over VRF and CMR indices in the prediction of incident cardiovascular diseases.</p
Surgical feasibility of ascending aorta manipulation after transcatheter aortic valve implantation:A computed tomography theoretical analysis
No full textAims: The expansion of TAVI will involve an increase in the frequency of emergent or late cardiac surgery after THV implantation. This study was designed to investigate the anatomical feasibility of surgical cross-clamp and aortotomy after TAVI through a post-TAVI CT-scan assessment. Methods and results: We retrospectively analysed 117 CTs acquired after TAVI procedures with high stent prostheses in three high-volume centres between October 2008 and May 2017. The mean distance observed between the innominate artery and the top of the transcatheter heart valve was 45±11 mm, being <30 mm in 8/117 (6.8%) patients and <20 mm in none. The mean distance between the sinotubular junction and the first free site for aortotomy was 22±7 mm (>20 mm in 78/117 [66.7%] cases). A total of 56/117 (47.9%) patients showed a complete continuous contact between the anterior aortic wall and the anterior part of the valve stent. Conclusions: Aortic cross-clamp appears not to be an issue when cardiac surgery is needed after TAVI; however, a careful and possibly higher aortotomy may be required. CT should be performed prior to planned cardiac surgery after TAVI to determine a safe positioning for aortic cross-clamp and aortotomy.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
EACVI survey on burnout amongst cardiac imaging specialists during the 2019 coronavirus disease pandemic
No full textAims The European Association of Cardiovascular Imaging Scientific Initiatives Committee conducted a global survey to evaluate the impact of the 2019 coronavirus disease (COVID-19) pandemic on the mental well-being of cardiac imaging specialists. Methods and results In a prospective international survey performed between 23 July 2021 and 31 August 2021, we assessed the mental well-being of cardiac imaging specialists similar to 18 months into the COVID-19 pandemic. One-hundred-and-twenty-five cardiac imaging specialists from 34 countries responded to the survey. More than half described feeling anxious during the pandemic, 34% felt melancholic, 27% felt fearful, and 23% respondents felt lonely. A quarter of respondents had increased their alcohol intake and more than half reported difficulties in sleeping. Two-thirds of respondents described worsening features of burnout during the past 18 months, 44% considered quitting their job. One in twenty respondents had experienced suicidal ideation during the pandemic. Despite these important issues, the majority of participants (57%) reported having no access to any formal mental health support at work. Conclusion The survey has highlighted important issues regarding the mental well-being of cardiac imaging specialists during the COVID-19 pandemic. This is a major issue in our sub-specialty, which requires urgent action and prioritization so that we can improve the mental health of cardiovascular imaging specialists
Light to moderate coffee consumption is associated with lower risk of death: a UK Biobank study
Full text linkAims: To study the association of daily coffee consumption with all-cause and cardiovascular (CV) mortality and major CV outcomes. In a subgroup of participants who underwent cardiovascular magnetic resonance (CMR) imaging, we evaluated the association between regular coffee intake and cardiac structure and function.Methods: UK Biobank participants without clinically manifested heart disease at the time of recruitment were included. Regular coffee intake was categorized into 3 groups: zero, light-to-moderate (0.5-3 cups/day) and high (>3 cups/day). In the multivariate analysis, we adjusted for the main CV risk factors.Results: We included 468,629 individuals (56.2 ± 8.1 years, 44.2% male), 22.1% did not consume coffee on a regular basis, 58.4% had 0.5-3 cups per day and 19.5% had >3 cups per day. Compared to non-coffee drinkers, light-to-moderate (0.5-3 cups per day) coffee drinking was associated with lower risk of all-cause mortality (multivariate HR = 0.88, 95%CI : 0.83-0.92; p < 0.001) and CV mortality (multivariate HR = 0.83, 95%CI : 0.74-0.94; p = 0.006), and incident stroke (multivariate HR = 0.79, 95%CI : 0.63-0.99 p = 0.037) after a median follow-up of 11 years. CMR data were available in 30,650 participants. Both light-to-moderate and high coffee consuming categories were associated with dose-dependent increased left and right ventricular end-diastolic, end-systolic and stroke volumes, as well as greater left ventricular mass. Conclusion: Coffee consumption of up to 3 cups per day was associated with favorable CV outcomes. Regular coffee consumption was also associated with a likely healthy pattern of CMR metrics in keeping with the reverse of age-related cardiac alterations
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Radiation safety for cardiovascular computed tomography imaging in paediatric cardiology: a joint expert consensus document of the EACVI, ESCR, AEPC, and ESPR
Full text linkChildren with congenital and acquired heart disease may be exposed to relatively high lifetime cumulative doses of ionizing radiation from necessary medical invasive and non-invasive imaging procedures. Although these imaging procedures are all essential to the care of these complex paediatric population and have contributed to meaningfully improved outcomes in these patients, exposure to ionizing radiation is associated with potential risks, including an increased lifetime attributable risk of cancer. The goal of this manuscript is to provide a comprehensive review of radiation dose management and cardiac computed tomography performance in the paediatric population with congenital and acquired heart disease, to encourage informed imaging to achieve indication-appropriate study quality at the lowest achievable dose
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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