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Minimally invasive videoassisted surgery for iatrogenic aortic root to right atrium fistula after incomplete percutaneous occlusion of patent foramen ovale: case report and review of the literature.
No full textSurgical management of aortic prosthetic valve endocarditis
No full textBackground: Infective endocarditis (IE) is still associated with high mortality and morbidity despite advances in diagnostic, medical and surgical management.
Aims: I. To report short- and mid-term results after surgical treatment of IE in the current era and to compare the results between native valve endocarditis (NVE) and prosthetic valve endocarditis (PVE). II. To prospectively compare the ability of electrocardiogram (ECG)-gated computer tomography (CT) and transoesophageal echocardiography (TEE) to diagnose aortic PVE. III. To report our experience with implantation of aortic homografts in patients with aortic PVE or NVE with abscess. IV. To report the outcome of all patients operated for aortic PVE at our institution over the past 20 years and to examine whether the results have improved over time.
Methods and methods: In Study I, outcome after all consecutive patients operated for IE from 2008 to 2015 (n=254) was analysed. In Study II, 27 consecutive patients with aortic PVE underwent 64-sliced ECG-gated CT and TEE, and the results were compared and related to surgical findings. In Study III, outcome and Quality of life (QoL) in patients (n=62) with aortic PVE or NVE with abscess operated with implantation of an aortic homograft were analysed. In Study IV, outcome after all consecutive patients operated (n=87) for aortic PVE from 1993 to 2013 was analysed.
Results: In Study I, overall 30-day mortality was 8.7% and there was no statistically significant difference in 30-day mortality between patients with NVE and PVE (7.7% vs 11.1%, p=0.31). Thirty-nine percent of the patients had severe perioperative complications. Overall survival at one and five years was 86% and 75%, respectively. In Study II, agreement was good between surgical findings and imaging with ECG-gated CT and TEE and very good for the combination of CT and TEE. ECG-gated CT identified more abscesses and thickened aortic root wall while TEE detected more valvular dehiscence and vegetations. In Study III, overall 30-day mortality was 15%. Thirty-five percent of the patients had severe perioperative complications. Cumulative survival was 82%, 78%, 75%, and 67% at one, three, five and ten years, respectively. QoL did not differ significantly between the homograft patients and an age- and gender-matched normal control group. In Study IV, overall 30-day mortality was 10%. Forty-one percent of the patients had severe perioperative complications. Cumulative survival was 81% at five years and 75% at ten years. Thirty-day mortality was higher (22% vs 3.6%, p=0.007) and five-year cumulative survival was lower (66% vs. 88% p=0.013) during the first decade.
Conclusions: Surgery for infective endocarditis was associated with high early mortality and a considerable complication rate. Long-term outcome was acceptable. Morbidity and mortality were comparable in NVE and PVE patients. ECG-gated CT had comparable diagnostic performance to TEE in patients with aortic PVE and may be a complement to TEE. Acute aortic PVE and NVE with abscess formation treated with aortic homograft had substantial early complication rate and mortality. Long-term survival and QoL were satisfactory in patients surviving the immediate postoperative period. Aortic PVE was associated with a high rate of early complications and substantial early mortality. Long-term survival was satisfactory. The results have improved markedly during the past decade
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
In patients undergoing surgical repair of post-infarction ventricular septal defect, does concomitant revascularization improve prognosis?
No full textA best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'In patients undergoing surgical repair of post-infarction ventricular septal defect (VSD), does concomitant revascularization improve prognosis?'. The scientific literature was reviewed by searching Medline, using Ovid interface, from 1950 to April 2009. Four hundred and five papers were found, of which 18 were deemed relevant to the topics. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes, and results of these papers were tabulated. Seven out of 18 papers showed statistical evidence of benefit of concomitant coronary artery bypass grafting (CABG) in patients undergoing surgical repair of VSD. They showed a benefit especially with complete revascularization. Another five papers recommended CABG with VSD even in the absence of statistical evidence. The reported papers showed a mortality benefit from 26.3% without revascularization down to 21.2% with revascularization and an actuarial survival at five years from 29 up to 72%. However, six out of 18 papers did not find any difference. The largest study in this area was by Jeppsson et al. where 119 patients underwent VSD repair with revascularization and 70 underwent VSD repair only, the mortality was 38% vs. 46% (P=0.29). Barker et al. compared a group of 23 patients undergoing repair of VSD only and 42 patients undergoing concomitant CABG. The in-hospital mortality was 39.2% vs. 26.2%, and the four-year survival rate was 33.2% and 88.2%, respectively. Lundblad et al. found that in 66 patients undergoing concomitant CABG out of 102 undergoing repair of VSD, complete revascularization and revascularization of the culprit artery, both resulted in improved 30-day survival and long-term survival. Muehrcke et al. reported on 75 patients undergoing surgical repair of post-infarction VSD. Out of those, 33 (44%) had a concomitant CABG. The authors found that concomitant CABG increases long-term survival when compared with patients with unbypassed coronary artery disease (CAD) (P=0.0015). We conclude that patients undergoing concomitant CABG to all the stenotic coronary arteries, supplying the non-infarcted area, fare better both in improved 30-day survival and long-term survival. The improvement of the collateral flow to the myocardium contributes to its better recovery
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