bluuebunny/crossref_metadata_2025 huggingface dataset:
Mineralogy-based brittleness prediction from surface seismic data: Application to the Barnett Shale
Authors: Perez Altamar Roderick , Marfurt Kurt
Published: August 2014

Differentiating brittle and ductile rocks from surface seismic data is the key to efficient well location and completion. Brittleness average estimates based only on elastic parameters are easy to use but require empirical calibration. In contrast, brittleness index (BI) estimates are based on mineralogy laboratory measurements and, indeed, cannot be directly measured from surface seismic data. These two measures correlate reasonably well in the quartz-rich Barnett Shale, but they provide conflicting estimates of brittleness in the calcite-rich Viola, Forestburg, Upper Barnett, and Marble Falls limestone formations. Specifically, the BI accurately predicts limestone formations that form fracture barriers to be ductile, whereas the brittleness average does not. We used elemental capture spectroscopy and elastic logs measured in the same cored well to design a 2D [Formula: see text] to brittleness template. We computed [Formula: see text] and [Formula: see text] volumes through prestack seismic inversion and calibrate the results with the [Formula: see text] template from well logs. We then used microseismic event locations from six wells to calibrate our prediction, showing that most of the microseismic events occur in the brittle regions of the shale, avoiding more ductile shale layers and the ductile limestone fracture barriers. Our [Formula: see text] to brittleness template is empirical and incorporates basin- and perhaps even survey-specific correlations of mineralogy and elastic parameters through sedimentation, oxygenation, and diagenesis. We do not expect this specific template to be universally applicable in other mudstone rock basins; rather, we recommend interpreters generate similar site-specific templates from logs representative of their area, following the proposed workflow.
Short-Selling Attacks and Creditor Runs
Authors: Liu Xuewen
Published: August 2014

This paper investigates the mechanism through which short selling of a bank's stocks can trigger the failure of the bank. In the model, creditors, who learn information from stock prices, will grow increasingly unsure about the bank's true fundamentals in facing noisier stock prices; thus a run on the bank is more likely because of creditors' concave payoff. Understanding this, speculators conduct short selling beforehand to amplify (il)liquidity and add noise to stock prices, triggering a bank run, and subsequently profit from the bank's failure. We show that short-selling attacks on a bank involve two runs: the aggressive run among speculators and the conservative run among creditors. These two runs interact and reinforce each other, with compound feedback loops that drastically increase the probability of the collapse of the bank. We discuss policy implications of the model.

This paper was accepted by Wei Jiang, finance.
Clarke Subgradients for Directionally Lipschitzian Stratifiable Functions
Authors: Drusvyatskiy Dmitriy , Ioffe Alexander D. , Lewis Adrian S.
Published: August 2014

Using a geometric argument, we show that under a reasonable continuity condition, the Clarke subdifferential of a semi-algebraic (or more generally stratifiable) directionally Lipschitzian function admits a simple form: The normal cone to the domain and limits of gradients generate the entire Clarke subdifferential. The characterization formula we obtain unifies various apparently disparate results that have appeared in the literature. Our techniques also yield a simplified proof that closed semialgebraic functions on Rn have a limiting subdifferential graph of uniform local dimension n.
Education in geriatric medicine for community hospital staff
Authors: O'Hanlon Shane , Liston Richard
Published: August 2014

Community hospitals provide many services for older people. They are mainly managed by nursing staff, with some specialist input. Little is known about education provided in these facilities. Most education in geriatric medicine is provided in hospitals, despite most elderly care being provided in the community. The authors surveyed senior nursing staff in Irish community hospitals to examine this area in more detail. Staff in all 18 hospitals in the Health Service Executive (South) area were invited to participate. The response rate was 100%. Sixteen of the 18 respondents (89%) felt staff did not have enough education in geriatric medicine. Just over half of hospitals had regular staff education sessions in the area, with a minority of sessions led by a geriatrician, and none by GPs. Geriatrician visits were valued, but were requested only every 1-3 months. Staff identified challenging behaviour and dementia care as the areas that posed most difficulty.
Exploring the concept of quality care for the person who is dying
Authors: Stefanou Nichola , Faircloth Sandra
Published: August 2014

The concept of good quality care for the patient who is dying is diverse and complex. Many of the actions that are being taken to increase the quality of care of the dying patient are based around outcome, uniformity of service and standardization of process. There are two main areas that are referred to when dealing with care of the dying patient; end-of-life care and palliative care.

High quality end-of-life care is increasingly recognized as an ethical obligation of health-care providers, clinicians and organizations, and yet there appears little evidence from the patients’ perspective. There are many national and local initiatives taking place to improve the quality of care people receive towards the end of their life. This being said initiatives alone will not achieve good quality care and deliver good patient experiences. Only clinicians working at the front line can truly influence the way in which quality is improved and good experiences delivered.
Reflect for success: recommendations for mentors managing failing students
Authors: Carr Jacqui , Heggarty Heather , Carr Marcia , Fulwood Deb , Goodwin Clare , Walker Wendy , Whittingham Katharine
Published: August 2014

Failing a student nurse for not meeting clinical competency on a practice placement can be a distressing and traumatic event for both student and community nurse mentor. This paper describes how a reflective model can be used to support practitioners’ to come to terms with the decision and action of failing a student and dealing with the aftermath of the final interview.
Decision making within a community provider organization
Authors: Berggren Ingela , Carlstrom Eric
Published: August 2014

Aim:

To explore community nurses’ experiences of decision making within the community provider organization.

Background:

Recent changes in health care with an increasing number of patients being cared for outside of institutions can put considerable pressure on the nurse with respect to decision making.

Methods:

In-depth interviews were performed with 6 registered nurses in two communities. The interviews were analysed by means of phenomenological hermeneutics.

Results:

The community nurses’ experiences of decision making were interpreted as spiders or octopuses, consultants and troubleshooters. The subthemes were; networking and structuring, responsibility, availability and knowledge, assessment power, information selection, avoiding rules and bypassing managers. In accordance with hermeneutical phenomenology, the findings were discussed and explained with reference to Ofstad's philosophy of freedom to make decisions.

Conclusion:

In their decision making, community nurses are committed to finding administrative solutions that satisfy patient needs.
Developing an online community of practice to empower health visitors: Findings from a pilot study
Authors: Ikioda Faith , Kendall Sally , Brooks Fiona , Reidy Claire
Published: August 2014

The Burdett Trust for Nursing funded a 2-year project to pilot an online community of practice to enable health visitors to share, manage and co-produce knowledge in a virtual space. The aim of the project was to develop a robust web-based tool to allow practitioners to share expertise and promote learning to empower them to exchange professional knowledge and best practice with other practitioners across organisational boundaries. In this paper, the authors reflect on the process of developing an online community of practice for health visiting, and report some initial findings and challenges from the pilot study.
Librarian as Futurist: Changing the Way Libraries Think About the Future
Authors: Mathews Brian
Published: August 2014

Are librarians preoccupied with the future? There are countless books, articles, blog posts, webinars, and conference presentations filled with speculation about what libraries will become. This is understandable with the emergence of new roles for libraries and librarians as we determine our identity across the digital landscape. This essay offers guidance for thinking about the future. By adopting the cognitive tools and mindsets used by practitioners of strategic foresight, library leaders can position their organizations for greater impact and value. Knowing how to discover, design, assess, and address possible future scenarios is becoming increasingly critical, and this skill should become part of our professional fluency.
Start a New Fire: Measuring the Value of Academic Libraries in Undergraduate Learning
Authors: Menchaca Frank
Published: August 2014

In the last two decades, fundamental changes in information distribution, in the general economy, and in the behaviors of faculty, students, and library staff have problematized the question of an academic library’s value and how it can be measured. This article reviews those changes and, drawing on research linked to the Collegiate Learning Assessment exam and Project Information Literacy, identifies undergraduate learning outcomes as an educational "pain point" that libraries are well-positioned to address. It argues that measuring libraries’ value in terms of supporting improved undergraduate learning outcomes will lead increased funding prospects and greater relevancy.
ELF awareness as an opportunity for change: a transformative perspective for ESOL teacher education
Authors: Sifakis Nicos C.
Published: August 2014

The paper discusses the challenges and opportunities that the English as a lingua franca (ELF) paradigm raises for ESOL teacher education. I argue that one of the prominent implications of the ELF paradigm for ESOL teachers is the need to review and ultimately change their convictions about key aspects of foreign language teaching, such as normativity, the role of native/non-native speakers, and the function of teacher feedback in the foreign language classroom. I review evidence from the ELF literature that supports such a perspective and discuss the kind of reflective reviewing that teachers need to engage in. I argue that, while the critical approach is certainly the right way to go, it is not enough. What is necessary is a more rigorous approach that would go beyond merely exposing teachers to the principles and criteria of ELF and prompt them to critically consider and ultimately transform their deeper convictions about these issues. I present a framework for such a transformative perspective that aims at educating the ELF-aware teacher.
Explanatory strategies in university courses taught in ELF
Authors: Gotti Maurizio
Published: August 2014

In the last few years many universities have internationalised their courses by offering them in English. Very often the lecturers remain the local ones, who adopt English as a means of instruction although they are not native speakers of that language. In many cases the teaching of such courses is assigned to foreign lecturers, who are not chosen specifically for their language competence but rather according to their expertise in the subject they are supposed to be teaching. As they are taught in English, these courses attract many students from other countries. The result is a typical ELF situation in which most lecturers and students – although they are not native speakers of English – use this language as a common means of communication and instruction.

The present paper examines communicative interactions taking place in such contexts. The data are taken from “international” courses on specialised disciplines offered by the University of Bergamo, recorded and transcribed according to the conventions adopted in the compilation of the ELFA Corpus (Mauranen et al. 2010). In particular, the first part of the paper examines the most common strategies employed by lecturers to explain the main specialised terms and technical concepts concerning the specific courses they are teaching, as well as those adopted to overcome the difficulties of comprehension experienced by their students. The second part of the paper takes into consideration the cooperative work carried out by both learners and teachers in the explanation/comprehension of specific topics in order to facilitate the achievement of the teaching/learning objectives of the courses.
EFL and ELF college students' perceptions toward Englishes
Authors: Tsou Wenli , Chen Fay
Published: August 2014

English as a Lingua Franca (ELF) is today a research area which has attracted a lot of attention. This paper builds on recent research in this field and explores Taiwanese English as a foreign language (EFL) and international students' (FLF) perceptions toward Englishes. The participants were (i) EFL sophomores who took college English courses (n = 1965) and (ii) ELF graduate students in an international MBA (IMBA) program (n = 97) in Taiwan. Comparing the survey results enables the researchers to investigate English learning perceptions between undergraduate students, who learn English as a foreign language, and IMBA students, who study in ELF classrooms and use English for academic learning to communicate with instructors and fellow students. In addition to survey, interview data were collected from 13 ELF students so that qualitative data were available for analysis. The result of this study suggests the need to reformulate English education in Taiwan so that English becomes an effective tool for learning and communication in academic ELF settings. This will involve raising awareness of English varieties, fostering cross-cultural understanding, and developing accommodation strategies to facilitate international communication.
Grammaticalization of reciprocal pronouns in Indo-Aryan: Evidence from Sanskrit and Indo-European for a diachronic typology of reciprocal constructions
Authors: Kulikov Leonid
Published: August 2014

This paper focuses on the evolution of the Old Indo-Aryan reciprocal pronoun anyo'nya- as well as some related forms, tracing its grammaticalization from the early Vedic period onwards until the beginning of the Middle Indic period. On the basis of a comparison of the history of this formation with similar processes documented in some other Indo-European branches (Greek, Slavic etc.), I uncover some basic mechanisms and scenarios of the evolution of reciprocal constructions attested in the history of Indo-Aryan languages in a diachronic typological context, offering a number of typological generalizations on the diachrony of reciprocals.
Preparation and characterization of nano biphasic calcium phosphate/poly-L-lactide composite scaffold
Authors: Yang Weizhong , Yi Yong , Ma Yuan , Zhang Li , Gu Jianwen , Zhou Dali
Published: August 2014

Nano biphasic calcium phosphate (BCP) particles were synthesized using the sol-gel method. As-prepared BCP particles were combined with poly-L-lactide (PLLA) to fabricate nano-BCP/PLLA composite scaffold through a series of processing steps containing solvent self-diffusion, hot-pressing, and particulate leaching. The composite had a suitable porous structure for bone tissue engineering scaffold. In comparison, micro-BCP/PLLA scaffold was studied as well. Nano-BCP particles were distributed homogeneously in the PLLA matrix, and much more tiny crystallites exposed on the surface of the pore wall. Due to the finer inorganic particle distribution in the PLLA phase and the larger area of the bioactive phase exposed in the pore wall surface, nano-BCP/PLLA scaffold had enhanced compressive strength, good bioactivity, and superior cell viability. A nonstoichiometric apatite layer could be rapidly formed on the surface of nano- BCP/PLLA when soaked in simulated body fluid. The MG-63 cell viability of nano-BCP/PLLA scaffold is significantly higher than that of micro-BCP/PLLA scaffold. Therefore, nano-BCP/PLLA composite may be a suitable alternative for bone tissue engineering scaffold.
Gas Turbine Fault Diagnosis Using Probabilistic Neural Networks
Authors: Loboda Igor , Olivares Robles Miguel Angel
Published: August 2014

Efficiency of gas turbine monitoring systems primarily depends on the accuracy of employed algorithms, in particular, pattern classification techniques for diagnosing gas path faults. In recent investigations many techniques have been applied to classify gas path faults, but recommendations for selecting the best technique for real monitoring systems are still insufficient and often contradictory. In our previous work, three classification techniques were compared under different conditions of gas turbine diagnosis. The comparative analysis has shown that all these techniques yield practically the same accuracy for each comparison case. The present contribution considers a new classification technique, Probabilistic Neural Network (PNN), and we compare it with the techniques previously examined. The results for all comparison cases show that the PNN is not inferior to the other techniques. We recommend choosing the PNN for real monitoring systems because it has an important advantage of providing confidence estimation for every diagnostic decision made.
Os códigos lingüísticos da rede e a paisaxe lingüística galega
Authors: Mosquera Castro Estefanía , Wellings Matthew P.
Published: August 2014

Neste artigo analízase a proxección social dos novos códigos lingüísticos xurdidos na esfera tecnolóxica e nomeadamente a través dos sistemas de comunicación mediatizada por computador. En particular, tenciona verificar, por unha parte, a súa presenza na linguaxe pu­blicitaria, esfera onde estas prácticas son cada vez máis habituais e, por outra, as súas repercusións na paisaxe lingüística, que manifesta unha moi alta concentración de textos publicitarios e onde estes novos sistemas de escrita están a gañar cada vez maior visibilidade. Os obxectivos que se perseguen son varios: primeiramente, constatar o grao de expansión dos sistemas de escrita xerados na Rede e describirmos a súa orixe, os condicio­nantes que impulsaron a súa creación e a súa conside­ración social; en segundo lugar, demostrarmos o grande potencial destes códigos en determinados ámbitos que exceden a esfera lingüística ou comunicativa en que se xeraron,concretamente na paisaxe lingüística galega. Para alén da dicotomía entre o galego e o español e a presenza das linguas estranxeiras, xulgamos relevante in­corporarmos estes usos gráficos, pois constitúen tamén un indicador de vitalidade lingüística. Compilamos un corpus representativo de datos para nos aproximarmos deste fenómeno desde unha perspectiva cualitativa, mais tamén cuantitativa. A través de exemplos concretos examinaremos as súas manifestacións, as motivacións que están detrás do seu uso e a súa transcendencia social. Os resultados obtidos subscriben as nosas hipóteses ini­ciais e evidencian, igualmente, a necesidade de adoptar­mos enfoques multidisciplinares que reflexionen sobre as novidades lingüísticas e que, deste modo, poñan de manifesto a realidade (socio)lingüística da Galiza.
Radionuclide Imaging for Assessment of Patients with Atrial Fibrillation
Authors: Miller Todd D , Askew J Wells ,   Division of Cardiovascular Diseases, Department of Internal Medicine, Gonda 5, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, US. E: miller.todd@mayo.edu,   Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic, Rochester
Published: August 2014

Atrial fibrillation is a common arrhythmia affecting more than 2 million adults in the US. There is a well-recognized association between atrial fibrillation and cardiovascular disease. Associated cardiovascular conditions include coronary artery disease (CAD), hypertension, left ventricular dysfunction (systolic and/or diastolic), valvular heart disease, pericardial disease, congenital heart disease and pulmonary embolus. Single-photon-emission computed tomography (SPECT) myocardial perfusion imaging (MPI) can be useful for assessment of underlying CAD in patients with atrial fibrillation. The decision to employ SPECT MPI in an individual patient with atrial fibrillation should depend on the clinical characteristics of the patient that generally would warrant the use of a SPECT study and not solely on the presence of atrial fibrillation.
The Future of European Electrophysiology – How to Improve the Quality of Care in Europe
Authors: Merino Jose L ,   Director, Arrhythmia–Electrophysiology Research Unit, La Paz University Hospital, Unidad de Investigación de Arritmias y Electrofisiología, Hospital General La Paz, P Castellana 261, 28046 Madrid, Spain. E: jlmerino@arritmias.net
Published: August 2014

Invasive management of heart rhythm disorders by catheter ablation and device implantation has been established as the therapy of choice for most cardiac arrhythmias, and the number of patients and complex procedures has increased dramatically. However, these procedures have an associated risk of serious complications and require fluoroscopy, which entails additional risks for both the patient and the operating personnel. All of these considerations justify the implementation of actions to guarantee quality and the creation of qualifications for the practice of these techniques in the interest of obtaining the greatest efficacy with the minimum possible risk to the patient and operating personnel. Attempts at quality improvement of electrophysiology in Europe should utilise a systematic approach incorporating various actions, including setting standards via guidelines and consensus recommendations, establishing the basal situation using registries and surveys, introducing pathways for common education with core curriculum documents, fostering motivation by promoting research, recognising excellence through accreditation systems and raising public awareness and public resources using public foundations and patient associations.
Surgical Management of Pulmonary Embolus
Authors: Large Stephen Ralph , Jenkins David Philip ,   Surgical Unit, Papworth Hospital, Papworth Everard, Cambridge, CB3 8RE, UK. E: stephen.large@papworth.nhs.uk,   Papworth Hospital, Cambridge
Published: August 2014

There is mounting evidence to guide the clinician in the management of both the acute presentation of pulmonary embolus and its chronic state. In this article we will review the role of surgery in both. Its role in acute presentation is not so clear despite 85 years passing since the first reported case of surgical pulmonary embolectomy. Pulmonary embolus is a particularly life-threatening complication when combined with shock, hypotension or right ventricular dysfunction. Essentially, surgical embolectomy has been reserved for high-risk patients. The current survival rate is around 70%. The treatment of choice for most patients with symptomatic chronic thromboembolic pulmonary hypertension is surgical disobliteration by pulmonary endarterectomy, a comparatively novel surgical procedure. This is the only treatment proved to offer significant symptomatic and prognostic benefit and should be distinguished from pulmonary embolectomy for acute embolus. The in-hospital survival rate (95%) for pulmonary endarterectomy in specialist centres is excellent, and patients enjoy a significant reduction in symptoms and increased life expectancy.
Radiation Minimisation and Outcome Maximisation in Cardiac Computed Tomograpy
Authors: Earls James P , Leipsic Jonathon A ,   Director, Cardiovascular Computed Tomography and Magnetic Resonance Imaging, Fairfax Radiology Consultants, 2272 Merrilee Dr, Fairfax, VA 22031, US. E: jpearls@yahoo.com,   Chairman, Department of Radiology, University of British Columbia, Vancouver
Published: August 2014

Recent reports have raised general awareness that cardiac computed tomography (CT) has the potential for relatively high effective radiation doses. While the actual amount of risk this poses to the patient is controversial, the increasing concern has led to a great deal of research on new CT techniques capable of imaging the heart at substantially lower radiation doses than was available only a few years ago. Methods of dose reduction include optimised selection of user-defined parameters, such as tube current and voltage, as well as use of new technologies, such as prospective triggering and iterative reconstruction. These techniques have each been shown to lead to substantial reduction in radiation dose without loss of diagnostic accuracy. This article will review the most frequently used and widely available methods for radiation dose reduction in cardiac CT and give practical advice on their use and limitations.
Evaluation of Diastolic Dysfunction Using Cardiac Magnetic Resonance Imaging
Authors: Pandey Tarun , Jambhekar Kedar ,   Department of Radiology, University of Arkansas for Medical Sciences, 159 Blackburn Drive, Little Rock, AR 72211, US. E: drtarunpandey@gmail.com,   Department of Radiology, University of Arkansas for Medical Sciences
Published: August 2014

Left ventricular (LV) diastolic dysfunction and diastolic heart failure (DHF) account for approximately 40–50% of all patients with congestive heart failure (CHF). Diastolic dysfunction can be evaluated directly by invasive cardiac catheterisation techniques or non-invasively by transthoracic echocardiography (TTE) or cardiac magnetic resonance (CMR) imaging. Due to its high spatial and temporal resolution, CMR is the accepted gold standard for evaluating ventricular systolic function. Using the cine-phase contrast technique, CMR can interrogate inflow through the mitral valve and pulmonary veins towards evaluation of diastolic dysfunction and has shown good correlation with TTE. Additionally, CMR can evaluate direct myocardial diastolic parameters that have no echo correlate, such as diastolic torsion rate. As CMR has the ability to characterise a range of diastolic impairments, it will likely become an important diagnostic test in the future, capable of comprehensive LV function evaluation. In this article, we focus on LV diastology, and review CMR methodology and parameters for the diagnosis of diastolic dysfunction.
Imaging Strategies for Coronary Sinus Annuloplasty
Authors: Messika-Zeitoun David , Jean-Michel Serfaty , Himbert Dominique , Vahanian Alec ,   Bichat Hospital, Cardiology Department, 46 rue Henri Huchard, 75018 Paris, France. E: david.messika-zeitoun@bch.aphp.fr; INSERM U698,   Radiology Department, Bichat Hospital, Paris,   Cardiology Department,   Cardiology Department
Published: August 2014

Percutaneous mitral annuloplasty has been introduced as a potential alternative to mitral valve surgery. Appropriate evaluation of the coronary venous system and patient selection are key factors for successful device implantation and for avoiding procedural complications. Computed tomography plays a key role and should be systematically performed as a screening test in patients considered for the procedure. It allows precise assessment of the venous system anatomy and its relationship with the coronary arteries and with the mitral annulus. Venous angiography, performed during the procedure, provides useful complementary information. It confirms computed tomography’s findings, provides final measurements based on the size of the device that should be implanted and guides and monitors the procedure.
Challenges in Oral Antiplatelet Therapy
Authors: Wong Pat , Shafique Umair ,   Senior Medical Writers, Touch Briefings,   Senior Medical Writers, Touch Briefings
Published: August 2014

The positive impact of oral antiplatelet therapy on the prevention and treatment of cardiovascular events is well-documented, especially in terms of reducing the risk of thrombotic complications in patients with acute coronary syndromes and those undergoing percutaneous coronary intervention. The oral antiplatelet agents aspirin and clopidogrel have become the mainstay of therapy. However, a major challenge still exists in the need to determine the optimal level of platelet inhibition that is required to obtain a balance between the prevention of ischaemic events and minimisation of the risk of bleeding in various clinical settings. In addition, clopidogrel is associated with inter-individual variability of platelet response and delayed onset and offset of action, which can influence the safety and/or efficacy of the treatment. These pharmacological limitations have led to the development of new oral antiplatelets, such as prasugrel, which has recently been approved, and ticagrelor, which is in late-stage clinical development. These newer agents are associated with improved rates of onset and/or offset of action, and offer more consistent antiplatelet effects.
Atrial Fibrillation in the Failing Heart – A Clinical Review
Authors: McMullan Lori L , Vergara Gaston , Marrouche Nassir F ,   Comprehensive Arrhythmia Research and Management Center, Division of Cardiology, School of Medicine, University of Utah,   Comprehensive Arrhythmia Research and Management Center, Division of Cardiology, School of Medicine, University of Utah,   Comprehensive Arrhythmia Research and Management Center, Division of Cardiology, School of Medicine, Director, Cardiac Electrophysiology Laboratory, Department of Internal Medicine, University of Utah Health Sciences Center, 30 North 1900 East, Salt Lake City, UT 84132, US. E: nassir.marrouche@hsc.utah.edu
Published: August 2014

Not only are atrial fibrillation (AF) and heart failure (HF) the most commonly encountered disease conditions in clinical practice, they are also associated with an increased risk of both morbidity and mortality. Both diseases are affiliated with maladaptive neurohormonal changes and remodelling of the heart. Treatment of AF has focused on prevention of thromboembolism, rate control and rhythm maintenance. Rhythm maintenance with anti-arrhythmic drugs has been relatively ineffective in maintaining patients in sinus rhythm, with the addition of increased adverse side effects. Rhythm control of AF via catheter radiofrequency ablation is a viable treatment option, with several studies showing improvement in ejection fraction, quality of life and the six-minute-walk test. Future multicentre randomised controlled trials are pending, the first being Catheter Ablation Versus Standard Conventional Treatment in Patients With Left Ventricular Dysfunction and Atrial Fibrillation (CASTLE-AF), to determine whether catheter ablation of AF is superior to conventional therapy for patients suffering from AF and HF.
3D Echocardiography in Mitral Valve Heart Disease – Is It the New Gold Standard?
Authors: Rana Bushra S , Lee Justin MS , Nihoyannopoulos Petros ,   Papworth Hospital NHS Foundation Trust, Cambridge, Consultant Cardiologist, Papworth Hospital NHS Foundation Trust, Papworth Everard, Cambridge, CB23 3RE, UK. E: bushra.rana@papworth.nhs.uk,   Papworth Hospital NHS Foundation Trust, Cambridge,   Imperial College Healthcare NHS Trust, London
Published: August 2014

Although cardiac structures exist in three dimensions, 2D echocardiography only provides information in a single tomographic plane, the orientation of which is determined by the ultrasound window. Accordingly, the use of geometrical assumptions and mental integration of information from multiple 2D images are needed to assess cardiac structures such as the mitral valve. Advances in ultrasound technology, improvements in terms of realtime 3D imaging and the development of 3D transoesophageal echocardiography probes have opened up further applications, such as pre-operative planning of mitral valve repair and intraoperative guidance of percutaneous valve interventions. This article aims to provide an overview of the applications of 3D echocardiography in the assessment and treatment of mitral valve disease in adults in current clinical practice.
Moving Towards Biomimicry – The Development of the Novel BioMime™ Sirolimus-eluting Coronary Stent System
Authors: Seth Ashok ,   Chairman, Chief Cardiologist, and Chairman, Cardiology Council, Fortis Group of Hospitals, Escorts Heart Institute and Research Centre, Okhla Road, New Delhi 110025, India. E: ashok.seth@fortishealthcare.com
Published: August 2014

Since the first reported use of percutaneous transluminal coronary angioplasty (PTCA), advances in the interventional cardiology arena have been fast-paced. Within the last 10 years, these developments have been exponential. Developers and clinicians are fast adapting from the learning curve awarded by the time-course of drug-eluting stent (DES) evolution. The BioMime™ sirolimus-eluting coronary stent is a new step towards a biomimicry concept. The stent is built on an ultra-low strut thickness (65µm) cobalt–chromium stent platform using an intelligent hybrid of close and open cells allowing for morphology-mediated expansion, and employs a well-known antiproliferative – sirolimus – that elutes from a biodegradable co-polymer formulation in 30 days and ensures high coating integrity and a low coating thickness of 2µm. The resultant stent demonstrated almost 100% endothelialisation at 30 days in pre-clinical models and 0% major adverse cardiac events (MACE) at six months in the primary efficacy and safety clinical study.
Drug–Device Interactions
Authors: Aliot Etienne , Brugada Josep ,   Department of Cardiology, University of Nancy, Hôpital Le Brabois, Vandoeuvre les Nancy, France. E: e.aliot@chu-nancy.fr,   Arrhythmia Section, Cardiovascular Institute, Hospital Clinic, University of Barcelona, Villarroel 170, 08036 Barcelona, Spain. E: jbrugada@clinic.ub.es
Published: August 2014

Implantable cardioverter-defibrillators (ICDs) have demonstrated utility in the prevention of sudden cardiac death. However, a fair proportion of ICD recipients commonly present with atrial fibrillation (AF), which necessitates antiarrhythmic drug (AAD) therapy to restore/maintain sinus rhythm and prevent further exacerbation of AF, which may result from the frequent co-existence of congestive heart failure. The use of AADs as an adjunctive therapy in ICD patients presents both benefits and drawbacks. Several studies have shown that AADs can reduce the incidence of inappropriate ICD discharges by modulating arrhythmias, thereby reducing symptomology and mortality rates. In these terms, some AADs may be more effective than others. It is always important to consider safety and tolerability in AAD therapy. In addition to known risks associated with sotalol in β-blocker-refractory patients and long-term amiodarone therapy, there are adverse side effects associated with AADs that can promote ICD discharge and even prevent proper ICD functioning through poor arrhythmia detection. Interest in the role of catheter ablation in ICD therapy and/or AADs is increasing owing to promising results from recent studies. However, there are many factors to consider and the potential for drug–device interactions and the resulting clinical implications must always be considered when selecting a therapeutic regimen.
Clinical Experience with a Novel, Irrigated, Flexible Tip Ablation Catheter to Optimise Therapy Delivery
Authors: Pappone Carlo , Giannelli Luigi , Santinelli Vincenzo ,   Department of Arrhythmology, Maria Cecilia Hospital, Via Corriera 1, 48010 Cotignola, (Ravenna), Italy. E: cpappone@gvm-vmc.it,   Department of Arrhythmology, Maria Cecilia Hospital, Cotignola, Ravenna,   Department of Arrhythmology, Maria Cecilia Hospital, Cotignola, Ravenna
Published: August 2014

Innovative technologies are being developed to make current ablation procedures safer and easier. Sometimes conventional ablation catheters cannot easily adapt to anatomical targets, making radiofrequency applications challenging, time consuming or even ineffective. The Cool Flex is a novel, flexible and fully-irrigated tip catheter with an innovative design and various angular orientations to better adapt the ablation tip to the surrounding tissue. Here, peliminary experience with this new ablation catheter is reported in the treatment of different tachyarrhythmias, including slow and accessory pathway ablation, cavotricuspid isthmus-dependent atrial flutter and atrial fibrillation. One or two radiofreqency applications may be sufficient to eliminate the arrhythmogenic substrate in most patients without complications.
Managing Cardiovascular Risk in Patients with Type 2 Diabetes – Challenges and Opportunities
Authors: Rydén Lars , Mellbin Linda , Malmberg Klas ,   Cardiology Unit, Department of Medicine, Karolinska Institutet, Department of Cardiology, Karolinska University Hospital, 171 76 Stockholm, Sweden. E: lars.ryden@ki.se,   Cardiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden,   Cardiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
Published: August 2014

The prevalence of diabetes and its associated complications, such as cardiovascular disease (CVD), has increased over recent years and is expected to continue to rise dramatically. People with diabetes have a poor prognosis, with a substantially increased risk of coronary heart disease, coronary death, non-fatal myocardial infarction, stroke, and other vascular deaths compared with non-diabetic subjects. Conversely, studies have also shown that many patients with CVD have undiagnosed dysglycaemia and that already impaired glucose tolerance and newly detected diabetes are associated with an impaired prognosis. Thus, screening for such conditions, preferably with oral glucose tolerance testing, should be performed in all patients with CVD. Guidelines advocate a multifactorial approach to the management of prediabetes, diabetes and CVD. This includes lifestyle modifications as well as targets for glycaemic control, blood pressure, lipids, and other cardiometabolic risk factors. Although clinical trial data have demonstrated that target-driven strategies can improve outcomes in patients with diabetes, the implementation and execution of these regimens in clinical practice needs to improve.
Choosing the Proper Candidate and Technique for Atrial Fibrillation Ablation
Authors: Shah Dipen ,   Service de Cardiologie, Hopital Cantonal de Geneve, Rue Gabriel-Perret-Gentil, 4, 1211 Geneve 14, Switzerland. E: dipen.shah@hcuge.ch
Published: August 2014

The increasing popularity of catheter ablation for atrial fibrillation has been associated with a variety of techniques and ablation strategies as well as widening indications. A critical analysis of outcomes after catheter ablation is necessary to discern those patients unlikely to benefit from catheter ablation in order to propose rate control strategies with confidence. Left atrial size, advanced age, long standing mitral valve disease, duration of atrial fibrillation as well as left atrial fibrosis are currently thought to be important parameters associated with poorer outcomes. Determining the best suited ablation techniques from amongst different strategies of pulmonary vein (PV) isolation, atrial and coronary sinus ablation for specific subgroups of patients may avoid unnecessary ablation and preserve contractile atrial myocardium.
Chronic Mechanical Circulatory Support for Patients with End-stage Heart Failure as a Definitive Treatment Option
Authors: Ganslmeier Patrycja , Schmid Christof ,   Department of Cardiothoracic Surgery, University Medical Center, Regensburg,   Department of Cardiothoracic Surgery, University Medical Center, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany. E: christof.schmid@klinik.uni-regensburg.de
Published: August 2014

Mechanical circulatory support for end-stage heart failure has become routine and is now increasingly used as definitive treatment. Several small devices qualify for this purpose, but only a few have gained US Food and Drug Administration (FDA) approval as yet. Several studies, including the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) study, the Investigation of Non-transplant-Eligible Patients Who Are Inotrope Dependent (INTrEPID) and the HeartMate (HM) II trial have confirmed a significantly improved quality of life and functional capacity after device placement. However, cerebrovascular events, infection and device malfunction still pose a considerable risk to patients and hinder widespread use.
Drug Release Profiles of Different Drug-coated Balloon Platforms
Authors: Heilmann Torsten , Richter Christian , Noack Heiko , Post Sabine , Mahnkopf Dirk , Mittag Antje , Thiele Holger , Hans-Reiner Figulla ,   AVIDAL Vascular GmbH, Halle,   VP Corporate Development & Clinical Research, AVIDAL Vascular GmbH, Heinrich-Damerow-Str. 4, Berlin, Germany. E: Christian.Richter@avidal.net,   AVIDAL Vascular GmbH, Halle,   AVIDAL Vascular GmbH, Halle,   IMTR GmbH, Rottmersleben,   IMTR GmbH, Rottmersleben,   University Leipzig, Heart Centre,   University Hospital Jena
Published: August 2014

Drug-coated balloons are a new tool for the treatment of de novo or in-stent stenosis; as yet little is known about the principle by which these devices apply their therapeutic agents during intervention. Concerns remain regarding clinical safety and efficacy of different coatings, mainly influenced by the amount of drug transferred into the arterial tissue and lost into the bloodstream. To assess whether the chemical or mechanical set-up influences drug migration and wash-off, we compared four paclitaxel-coated balloon platforms differing in surface structure (folded versus non-folded) and coating compounds (pure paclitaxel versus paclitaxel plus excipient) in a porcine coronary model. The study revealed high wash-off rates for all devices, exceeding 54.4% of the initial coating contents. In terms of tissue concentration significant differences could be observed between the coating compounds independently from the device platform. For the paclitaxel versus paclitaxel plus excipient balloons tissue concentrations of 0.02 and 0.33μg/mm2, respectively (p<0.01), were detected; for the paclitaxel versus paclitaxel plus excipient-wrapped balloons tissue concentrations were 0.13 and 0.53μg/mm2, respectively (p=0.04). The main driver of drug migration from drug-coated balloon surfaces into arterial tissue is the chemical set-up of the coating. Hydrophilic excipients allow higher tissue concentrations of paclitaxel independent from the mechanical platform. The wash-off from the surface coating remains an unsolved safety issue and may be solved by mechanical modifications of these devices.
Acute Digital Ischaemia – What the Radiologist Needs to Know
Authors: Edjlali-Goujon Myriam , Alison Daniel ,   Centre d’Innovation Technologique, Centre Hospitalier Régional et Universitaire Tours, Hôpital Bretonneau, 2 Boulevard Tonnellé, 37044 Tours, France. E: myriam.edjlali@gmail.com,   Centre d’Innovation Technologique, Centre Hospitalier Régional et Universitaire Tours
Published: August 2014

Digital ischaemia is an uncommon pathology with multiple aetiologies, many of which are poorly understood. Imaging plays an important part in diagnosing curable causes. Digital substraction angiography (DSA) remains the gold standard for the study of the pathology of digital ischaemia. However, the improved spatial resolution and 3D image-processing tools of computed tomographic angiography (CTA) have led to its more recent application in the analysis of small and distal vessels. CTA is advantageous in that it provides both luminal and soft tissue imaging. It also yields a precise anatomical depiction of the vascularisation of the hand: the structure of the palmar arch is highly variable, an understanding of which is crucial when considering the source of blood supply to the arteries of the fingers. Here, we present a retrospective study of 32 patients with typical cases of the main aetiologies of digital ischaemia, all of whom underwent DSA. Eight patients suspected of hypothenar hammer syndrome additionally underwent CTA. In this study, we promote the use of CTA as a minimally invasive technique to clearly describe the localisation and extent of vessel injury.
Persistent Chest Pain in Absence of Angiographic Significant Coronary Artery Disease is Associated with Permanent Myocardial Perfusion Defects in Magnetic Resonance Imaging in Post-menopausal Women
Authors: Modena Maria Grazia , Nuzzo Annachiara , Rossi Rosario , Lammirato Anna , Fiocchi Federica , Ligabue Guido , Torricelli Pietro , Romagnoli Renato ,   Institute of Cardiology, Policlinico Hospital, University of Modena and Reggio Emilia, Via del Pozzo, 71. 41100 Modena, Italy. E: mariagrazia.modena@unimore.it,   Institute of Cardiology,   Institute of Cardiology,   Institute of Cardiology,   Institute of Radiology, University of Modena and Reggio Emilia, Policlinico Hospital, Modena,   Institute of Radiology, University of Modena and Reggio Emilia, Policlinico Hospital, Modena,   Institute of Radiology, University of Modena and Reggio Emilia, Policlinico Hospital, Modena,   Institute of Radiology, University of Modena and Reggio Emilia, Policlinico Hospital, Modena
Published: August 2014

We studied a population of post-menopausal women with persistent chest pain (PChP) in order to investigate the relationship between myocardial perfusion at rest and during a stress test using magnetic resonance imaging (MRI). Our goals were to document whether transient myocardial perfusion is induced by dipyridamole infusion and if perfusion defects are also present at rest. The study population consisted of 45 consecutive women (mean age 57.6±8.7 years), who reported chest pain symptoms. PChP was defined as self-reported continuing chest pain after one year. We compared the results of the perfusion MRI studies in subgroups with and without obstructive coronary artery disease (CAD). The latest tools and technologies of Synapse™ Cardiovascular – Fujifilm’s cardiovascular (CV) image and information management system – helped us to achieve clear and comprehensive outcomes. In the group of women with PChP and non-obstructive CAD, 16 of 34 (48%) showed a well-evident left ventricular perfusion defect at baseline (four in one segment; eight in two segments and four in three or more segments). The localisation of the perfusion defects – seen using Synapse Cardiovascular – were anteroapical (n=6); septal (n=10); and inferoor inferolateral (n=4). These defects were ‘permanent’ or ‘fixed’, i.e. were present at rest and were neither induced nor modified by the administration of dipyridamole. In any of the women with CAD we found these anomalies. ‘Fixed’ perfusion defects at MRI – probably due to permanent damage of the coronary microcirculation – suggest a disease state typical for post-menopausal women with PChP.