1,720,971 research outputs found
Perforated Aneurysms of left side Valves During active infective Endocarditis Complicating hipertrophic obstructive cardiomyopathy
No full textThe most frequent site of vegetative lesion in patients with hypertrophic cardiomyopathy is anterior mitral leaflet, due to chronic endocardial trauma arising from systolic anterior motion. We describe three cases of serious infective endocarditis complicated lesions (vegetation, aneurysm and perforation) on aortic and mitral valves, in patients with obstructive hypertrophic cardiomyopathy. In particular, we observed how severe valvular damage and dysfunction, combined with particular hemodynamic conditions, are followed by adverse clinical outcome. We performed transthoracic echocardiogram and transoesophageal echocardiography studies to define morphologic and hemodynamic features of infection, deciding the proper therapy and we planned the echocardiographic follow-up
Epicardial Real Time 3D Echocardiography with the Use of a Pediatric Transthoracic Probe: Proposal for a Technical Approach
No full textObjective: The aim of the present study was to suggest a
simple and comprehensive method for performing real-time
3-dimensional (3D) epicardial echocardiography with a pediatric
probe small enough for the surgical field. Intraoperative
echocardiography is a necessary tool for planning and
performing cardiac surgery. Although epicardial intraoperative
echocardiography is intended for few patients, it is a
part of an exhaustive approach to intraoperative echocardiography.
Design: An observational feasibility study.
Setting: A community hospital, single-institutional study.
Participants: Eighty consecutive adult patients undergoing
cardiac surgery.
Interventions: All patients were examined with 3D epicardial
echocardiography before and after cardiopulmonary bypass;
x-plane, live 3D, and 3D full-volume imaging modalities
were systematically recorded. Feasibility and acquisition
time were assessed. The image quality was evaluated by 3
independent surgeons.
Measurements and Main Results: Four sequential positions
were determined to achieve a complete 3D heart
examination focused on the structure of most interest.
Acquisition plus elaboration did not require more than 20
minutes.
Conclusions: Three-dimensional epicardial echocardiography
is feasible, and in the x-plane modality it is quicker than
standard epicardial 2-dimensional examination. According
to the judgment of independent observers, it provides highquality
and reproducible images, which are particularly valuable
for mitral valve repair
Use of Nuclear Magnetic Resonance Imaging Angiography to Follow-Up Arterial Remodeling in an Animal Model
Full text linkAppropriately sized arteries in small animals may be possible models for studying the remodeling process as occurs after arterial balloon injury in humans. Magnetic resonance imaging (MRI) is able to noninvasively image tissue in vivo. To date, small animal angiog raphy models have mostly used research-dedicated instruments and resolution, which are not universally available.Experiments were carried out on a rat aorta model of remodeling in vivo (n=40). Arteries were injured by oversized balloon dilation; control arteries were uninjured. Angiography imaging was performed immediately before sacrifice with an unmodified clinical MRI unit, a 1.5 Tesla MR tomograph with a 20-cm-diameter coil. Longitudinal MRI pictures of the aorta and morphometry of tissue sections to measure luminal and arterial wall areas were analyzed with use of computer-assisted techniques.Comparison of dimensions demonstrated correlation between MRI and histology measurements of the lumen. MRI and morphometry showed a gradual increase in mean luminal area over 6 weeks following injury. The lumen increase correlated with total arterial area and thickness.In this rat aorta model, remodeling documented at histology was followed-up in vivo. The use of such clinical MRI scanners has potential to reduce animal numbers needed to follow-up the remodeling process after therapeutic intervention
Role of transthoracic and transesophagealechocardiography in predicting embolic events in patients with active infective endocarditis involving native cardiac valves
No full textSome studies describe an increased risk for emboli in infective endocarditis patients with large (>10 mm) and mobile vegetations. Other studies fail to demonstrate the above relation. Most studies have been performed using transthoracic echocardiography or with a monoplane transesophageal approach. The present study examines whether distinctive characteristics of vegetative lesions detected by transthoracic and multiplane transesophageal echocardiography are predictive of embolic risk. We reviewed both transthoracic and transesophageal echocardiograms of 57 patients with diagnosis of acute infective endocarditis and no documented or suspected previous embolic events. We evaluated site, length, width, mobility, and echodensity of vegetations. Twenty-five patients (44%) had embolic events. No statistical differences in age, sex distribution, location of endocarditis, or offending pathogens between embolic (n = 25) and nonembolic (n = 32) patients were found. There were no differences in any of the echo characteristics of vegetations detected by transthoracic and transesophageal approach in embolic and nonembolic groups. Thus, transthoracic and transesophageal characteristics of vegetations are not helpful in defining embolic risk in patients with infective endocarditi
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
Left Atrial Minimum Volume Is The Most Powerful Predictor Of Adverse Cardiovascular Events
No full textDifferentiation of hypertrophic cardiomyopathy from other forms of left ventricular hypertrophy by means of three-dimensional echocardiography.
No full textVariations 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
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