1,721,024 research outputs found
Intravascular Lithoplasty for the Treatment of Calcified Plaques: A New Tool for the Interventionist
No full textPatient selection, procedural planning and interventional guidance for non-valvular structural intervention
No full textPercutaneous non-valvular structural interventions, encompassing patent foramen ovale, atrial or ventricular septal defect closure and left atrial appendage closure, are usually performed in young and healthy patients and represent a valid alternative to pharmacological or surgical interventions. In order to minimize procedural and device related complications, a careful pre-procedural planning together with an accurate intra-procedural imaging are crucial to improve patient’s outcome. In this article, we review currently available evidence on patient selection, procedural planning and interventional guidance helping physician to determine who will derive the most benefit from the procedure
Cerebral protection during transcatheter aortic valve implantation: An updated systematic review and meta-analysis
No full textBackground--The use of embolic protection devices (EPD) may theoretically reduce the occurrence of cerebral embolic lesions during transcatheter aortic valve implantation. Available evidence from single studies is inconclusive. The aim of the present metaanalysis was to assess the safety and efficacy profile of current EPD. Methods and Results--Major medical databases were searched up to December 2017 for studies that evaluated patients undergoing transcatheter aortic valve implantation with or without EPD. End points of interest were 30-day mortality, 30-day stroke, the total number of new lesions, the ischemic volume per lesion, and the total volume of lesions. Eight studies involving 1285 patients were included. The EPD delivery success rate was reported in all studies and was achieved in 94.5% of patients. The use of EPD was not associated with significant differences in terms of 30-day mortality (odds ratio 0.43 [0.18-1.05], P=0.3) but it was associated with a lower rate of 30-day stroke (odds ratio 0.55 [0.31-0.98], P=0.04). No differences were detected with respect to the number of new lesions (standardized mean difference -0.19 [-0.71 to 0.34], P=0.49). The use of EPD was associated with a significantly smaller ischemic volume per lesion (standardized mean difference, -0.52 [-0.85 to -0.20], P=0.002) and smaller total volume of lesions (standardized mean difference, -0.23 [-0.42 to -0.03], P=0.02). Conclusions--The use of EPD is not associated with a reduced rate of mortality and new ischemic cerebral lesions. The use of EPD during transcatheter aortic valve implantation seems to be associated with a lower 30-day stroke rate, although this result is driven by a single nonrandomized study. The use of EPD is associated with a smaller volume of ischemic lesions, and smaller total volume of ischemic lesions
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
What role for transcatheter mitral valve replacement?
No full textDespite the safety and efficacy of transmitral valve repair techniques, transcatheter mitral valve replacement (TMVR) has emerged as a potential treatment option for patients with severe mitral regurgitation at high or prohibitive surgical risk. To date, over 250 high-risk patients with severe mitral regurgitation have been treated with 10 different TMVR devices, demonstrating the feasibility of this technique. Parallel to the potential advantages of this procedure (reproducible mitral regurgitation reduction, possibility of targeting all potential anatomic variations), many challenges has emerged during the design and implantation phases. Further larger studies with longer follow-up are needed to evaluate safety and efficacy of TMV
Cerebrovascular events
No full textOne of the most important complications of transcatheter aortic valve implantation (TAVI) is represented by cerebrovascular events, often associated with a significant increase of postprocedural mortality and disability. This chapter describes incidence, predictors and possible preventive strategies of cerebrovascular events during TAVI. It is well known that TAVI is associated with an inevitable risk of neurological complications and their incidence has been studied and compared to the one related to surgical aortic valve replacement (SAVR) in many studies. In a study enrolling intermediate‐risk populations, stroke incidence after TAVI was inferior to the one after SAVR. Postprocedural stroke incidence follows a bimodal distribution. Cerebral debris embolization during TAVI is frequent and, if searched by neuroimaging modalities, almost constant. However, initial study data have shown that it is easily preventable with the use of embolic protection devices
A patient-specific algorithm to achieve commissural alignment with Acurate Neo: The sextant technique
No full textAims: The aim of this proof-of-concept study was to investigate safety and efficacy of a CT-scan based patient-specific algorithm to maximize coronary clearance and secondarily to achieve anatomically correct commissural alignment with the Acurate Neo device. Method and results: A total of 45 consecutive patients undergoing TAVR with the Acurate Neo THV were prospectively enrolled in the study. Mean age was 81.6 ± 5.5 years, mean STS score was 6.1 ± 3.7. Device success rate was 100%. Aim of the technique was to rotationally deploy the TAVR device with a commissure lying on the bisector between the coronary ostia as calculated on the pre-procedural CT-scan. At post-TAVR CT-scan, coronary clearance was achieved in 98% of patients with no cases of severe coronary artery overlap. In 42 out of 45 patients, THV was aligned or, at most, mildly misaligned; there were 2 cases of moderate misalignment without any case of severe misalignment. Post-TAVR selective coronary artery engagement was attempted and succeeded in all patients (100%). Conclusion: Our CT-scan based patient-specific algorithm is safe and proven to be effective in avoiding coronary artery overlap and providing commissural alignment with Acurate Neo in all treated patients
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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