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    How to evaluate the outflow tract of LVAD after minimally invasive implantation by 3D CT-scan

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    During a minimally invasive implantation technique, the outflow graft of left ventricular assist device (LVAD) is tunnelled blindly through the pericardium or left pleura, with an inability to assess for twisting or malposition. Three-dimensional computed tomography scan (CT-scan) has a role in qualitative evaluation of the different outflow tract configurations. The different surgical minimally invasive approaches include: (a) mini-sternotomy and left mini-thoracotomy, (b) right mini-thoracotomy and left mini-thoracotomy, (c) subclavian artery access and left mini-thoracotomy. The outflow graft could be anastomosed to the left axillary artery or the ascending aorta. CT-scan reconstruction using syngo InSpace4D (Siemens, Muenchen, Germany) was used to provide fast segmentation and high-resolution images. The 3D reconstructions permit an evaluation of different anastomosis configurations and to assess the route of outflow graft

    Valve surgery in octogenarians: does it prolong life?

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    Objectives: Age-related degenerative heart-valve disease is a health issue in the present era. Octogenarians are frequently affected by concomitant diseases and, with the present lack of resources, the risk/benefit of valvular replacement therapy poses serious medical, economical and political challenge. We analysed the long-term survival of 346 octogenarians who underwent 352 operations between 1 January 1987 and 1 January 2009 and we compared it with the survival of the general population, matched for age, sex and operative year. Methods: The total follow-up was of 1352 years, maximum 15.7 years and was nearly complete except for a single foreigner. Heart diseases, concomitant pathologies, complications and actuarial survival of this study group were compared with 4649 younger counterparts, who received 5416 operations during the same time frame. Octogenarians were sorted by age, sex and operative year and the expected survival was calculated by applying US survival rate and added to the Kaplan-Meier plot for visual comparison. Results: A total of 279 aortic, 38 mitral and 35 mitro-aortic valves were replaced or repaired using 357 bioprostheses, 18 mechanical prostheses, 12 reparative operations and 24 re-operations. A total of 75% of patients were younger than 84 years, 95% were younger than 87 years and 99% younger than 90 years. Sex prevalence was 215 female versus 131 male. Operative (30 days) mortality was 5.5% and overall survival was 84.3% at 1 year, 65.4% at 5 years, 27.3% at 10 years and 5.4% at 15 years. The expected survival of the age-, sex-, operative year-matched population was 26.9% at 10 years and 7.9% at 15 years. Female operative mortality was 5.9% and survival was respectively 86.3%, 70.2%, 27.5% and 9.1%, male mortality was 4.5% and survival was respectively 81%, 56.7%, 28.8% and 0% (p = 0.16). Expected female survival was 30% at 10 years and 10% at 15 years versus 22% and 5.6%, respectively, in males. Six octogenarians underwent re-operation, with one death. Conclusions: Despite the highest prevalence of concomitant diseases and the requirement of additional resources for the detection and neutralisation of risk factors, heart-valve operations in octogenarians offer excellent results that compare favourably with the expected survival of the age-, sex- and operative year-matched population, particularly after primary operations. © 2009 European Association for Cardio-Thoracic Surgery

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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
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