1,720,960 research outputs found
TAVI between a rock and a hard place in a transplanted heart
No full textWe describe a 61-year-old male patient at our institution who was being reviewed by the heart team for consideration of transcatheter aortic valve intervention. Gated cardiac computed tomography revealed extensive eccentric calcification of the left ventricular outflow tract (LVOT) extending into the mitral valve leaflet and a large aortic annulus (33 mm; mean annular diameter/area, 854 mmsup2;). This is larger than all recommended manufacturer annular size limits, although observational data support the use of both Edwards Sapien 3 and Medtronic Evolut R in such annuli
Sex differences in computed tomography coronary stenosis severity versus flow impairment and impact on revascularization, clinical events and healthcare costs: a FORECAST substudy
No full textBackground: the impact of sex related differences in coronary atheroma and flow impairment severity on clinical events and costs remains unclear.Methods and Results: this is a secondary analysis of patients with stable coronary artery disease (CAD) who underwent both coronary computed tomography angiography (CCTA) and fractional flow reserve derived from computed tomography (FFRCT) as part of the FORECAST trial, investigating: (a) the relationship between coronary stenosis severity on CCTA and FFRCT by sex and (b) the association with revascularization, resource utilization and adverse clinical events. 212 patients (64 female participants, 32.1%) and 1245 vessels were included. There was no significant sex difference in the frequencies of significant (38.2% of females vs 51.3% of males, p=0.073) but female participants had significantly less coronary flow impairment, according to the presence of at least one FFRCT≤0.8 (47.0% vs 71.5%, p=0.008). Female subjects underwent fewer revascularization procedures (23.5% vs 42.3%, p=0.014), less CABG (2.9% vs 13.1%, p=0.025) and were less likely to be on statin treatment (72.0% vs 84.7%, p=0.022) by 9-month follow-up. This resulted in lower overall healthcare costs for female participants compared with male counterparts (median total cost £1276 vs £2051, p=0.014). In multivariable Cox analysis the presence of significant CAD (HR 2.91; 95% confidence interval [CI] 1.30-6.51) and having a positive FFRCT (HR 4.11; 95% CI 1.15-14.69) were independent predictors of MACE at 9-months, whereas sex was not statistically significant (p=0.13).Conclusions: there are significant sex differences in the anatomico-functional assessment of coronary artery disease leading to differences in clinical management, costs and adverse events. <br/
Frequency and impact of incidental findings on computed tomography during work-up for transcatheter aortic valve implantation: single centre experience and review of the literature
No full textOBJECTIVE: To assess the frequency and impact of incidental findings (IF) on CT during work-up for transcatheter aortic valve intervention (TAVI).METHODS: A consecutive cohort of patients referred for consideration of TAVI who underwent a CT scan between 2009 and 2018 were studied retrospectively. CT reports were reviewed for the presence of IFs and categorised based upon their clinical significance: (a) insignificant-findings that did not require specific treatment or follow-up; (b) intermediate-findings that did not impact on the decision-making process but required follow-up; (c) significant-findings that either required urgent investigation or meant that TAVI was clinically inappropriate.RESULTS: A total of 652 patients were included, whose median age was 82 years. One or more insignificant IF was found in 95.6% of patients. Intermediate IFs were documented in 5.4%. 91 (14%) patients had at least one significant IF. These included possible malignancy in 67 (74%). The ultimate decision to offer aortic valve intervention was only changed by the presence of an IF in 3.5% of cases.CONCLUSION: Clinically significant IFs are detected in more than 1 in 10 of patients undergoing CT as part of a TAVI work-up, although just over half of these patients still receive aortic valve intervention.ADVANCES IN KNOWLEDGE: This study is the largest UK cohort, which, when combined with a review of existing literature, provides a clear picture of the frequency and clinical impact of IFs found at CT for TAVI assessment.</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
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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