1,720,979 research outputs found

    [Does a woman's heart beat faster?]

    No full text
    Recent publications have identified a different epidemiological prevalence related to sex in some of the most common supraventricular and ventricular arrhythmias. This fact is attributed to the effect of sex hormones on myocardial cell electrophysiology. Women, in particular, have a higher prevalence than males with regard to intranodal reentrant tachycardia, idiopathic monomorphic ventricular tachycardia and ventricular arrhythmias in congenital or acquired long QT syndrome. A higher incidence in females with regard to complications during atrial fibrillation has also been reported. This paper examines data from the literature regarding gender differences in the prevalence of the most common arrhythmias, the causes of these differences, and some discriminating aspects related to female sex in the architecture of published clinical studies

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    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

    A Questionable Indication For ICD Extraction After Successful VT Ablation

    No full text
    Sustained ventricular tachyarrhythmias represent a kind of complication shared by a number of clinical presentations of heart disease, sometimes leading to sudden cardiac death. Many efforts have been made in the fight against such a complication, mainly being represented by the implantable cardioverter defibrillator (ICD). In recent years, catheter ablation has grown as a means to effectively treat patients with sustained ventricular arrhythmias, in the contest of different cardiac substrates. Since carrying an ICD is associated with a potential risk deriving from its possible infective or malfunctioning complications, and given the current effectiveness of lead extraction procedures, it has been thought not to be unreasonable to ask ourselves about how to deal with ICD patients who have been successfully treated by means of ablation of their ventricular arrhythmias. To date, no control data have been published on transvenous lead extraction in the setting of VT ablation. In this paper we will review the current evidence about ICD therapy, catheter ablation of ventricular arrhythmias and lead extraction, trying to outline some considerations about how to face this new clinical issue

    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 link
    We 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

    Prevention of sudden cardiac death: from wearable to subcutaneous cardioverter defibrillator

    No full text
    The implantable cardioverter defibrillator (ICD) is today an indisputable evidence-based treatment for cardiac sudden death both in primary and secondary prevention. However many clinical conditions that would represent an indication to ICD implantation, according to guidelines, may be potentially reversible or may be accompanied by temporary contraindications to the implant. Moreover transvenous cardioverter defibrillator implantation still carries a not negligible risk of complications both acutely and at follow-up. The Wearable Cardioverter Defibrillator and the Subcutaneous Defibrillator are two recently developed technologies that can potentially overcome the aforementioned limitations of traditional transvenous ICDs. This review will discuss the main aspects of these 2 technologies, the data coming from clinical experiences and future perspectives

    Large, single-center experience in transvenous coronary sinus lead extraction: procedural outcomes and predictors for mechanical dilatation

    No full text
    Background: The aim of this study was to evaluate procedural outcomes of coronary sinus (CS) lead extraction, focusing on predictors and need for mechanical dilatation (MD) in the event that manual traction (MT) is ineffective.Methods: The study assessed results in 145 consecutive patients (age 69 +/- 10 years; 121 men)-a total of 147 CS pacing leads-who underwent transvenous CS lead removal between January 2000 and March 2010.Results: All leads but one (99%) (implantation time 29 +/- 25 months) were successfully removed. MT was effective in 103 (70%), and MD was necessary in the remaining 44 (30%) procedures. In multivariate analyses, unipolar design (odds ratio [OR] 3.22, 95% confidence interval [CI] 1.43-7.7; P = 0.005) and noninfective indication (OR 4.8, 95% CI 1.8-13, P = 0.002) were independent predictors for MD (P < 0.0001), with a predictive trend for prior cardiac surgery (OR 2.2, 95% CI 0.98-5.26; P = 0.06). Five (3.4%) complex procedures required a transfemoral vein approach (TFA) or repeat procedure. No deaths occurred, and there was one major complication (0.7%), cardiac tamponade, after MT. No complication predictors were identified.Conclusions: CS leads were safely and effectively removed in nearly all patients, and 70% were removed with MT alone; 30% required MD. Preoperative predictors suggesting the need for MD or TFA were noninfective indication and unipolar lead design. Complications were rare, and there was no predictable pattern among MT or MD removal techniques. (PACE 2012; 35:215-222

    Where is the future of cardiac lead extraction heading?

    No full text
    Introduction: Transvenous lead extraction (TLE) is the gold standard for lead removal. The increasing rate of cardiac implantable electronic device (CIED) implantations and of CIED related complications highlight the importance of transvenous lead extraction.Areas covered: The TLE scenario is constantly changing. Optimizing lead related technology and improving TLE practice across the world are the cornerstones to improving safety and efficacy. We review the state of the art in TLE, focusing on potential future implications and improvements in terms of skills and technologies.Expert commentary: The increased number of extractions will increase the necessity of safe and effective TLE. New technologies, techniques and appropriate training is warranted across the world

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    We 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
    corecore