Transapical aortic valve implantation in patients with severely depressed left ventricular function

ObjectivesTransapical aortic valve implantation significantly reduces operative risk in elderly patients with aortic valve stenosis and comorbidities. However, it is unknown whether this procedure is feasible in patients with advanced heart failure.MethodsBetween April 2008 and July 2010, 258 patients underwent transapical aortic valve implantation. Twenty-one patients had advanced heart failure with decompensation and a left ventricular ejection fraction of 10% to 25%. The mean age of these patients was 74 ± 11 years (range, 36-88 years). The mean left ventricular ejection fraction was 20% ± 5% (range, 10%-25%). Mean logistic EuroSCORE was 66% ± 21% (range, 27%-97%) and mean Society of Thoracic Surgeons score 33% ± 25% (range, 4%-90%). Nine patients were operated on using femorofemoral cardiopulmonary bypass and 12 without.ResultsTechnical success of the procedure was 100% with no conversion to conventional surgery. The mean time of cardiopulmonary bypass was 27 ± 25 minutes (range, 6-81 minutes). Postoperatively, the left ventricular ejection fraction increased to 38% ± 12% (range, 20%-60%). There were no postoperative neurologic complications. A new pacemaker implantation was needed in 2 (10%) patients. The 30-day mortality was 4.8%. Survival at 1, 3, 12, and 24 months was 95%, 81%, 76%, and 62%, respectively.ConclusionsTransapical aortic valve implantation can be performed safely in patients with decompensated heart failure or even in the presence of cardiogenic shock

Transapical mitral valve implantation for treatment of symptomatic mitral valve disease: a real-world multicentre experience.

AIMS Transcatheter mitral valve implantation (TMVI) is a new treatment option for patients with symptomatic mitral valve (MV) disease. Real-world data have not yet been reported. This study aimed to assess procedural and 30-day outcomes of TMVI in a real-world patient cohort. METHOD AND RESULTS All consecutive patients undergoing implantation of a transapically delivered self-expanding valve at 26 European centres from January 2020 to April 2021 were included in this retrospective observational registry. Among 108 surgical high-risk patients included (43% female, mean age 75 ± 7 years, mean STS-PROM 7.2 ± 5.3%), 25% was treated for an off-label indication (e.g. previous MV intervention or surgery, mitral stenosis, mitral annular calcification). Patients were highly symptomatic (New York Heart Association [NYHA] functional class III/IV in 86%) and mitral regurgitation (MR) was graded 3+/4+ in 95% (38% primary, 37% secondary, and 25% mixed aetiology). Technical success rate was 96%, and MR reduction to ≤1+ was achieved in all patients with successful implantation. There were two procedural deaths and 30-day all-cause mortality was 12%. At early clinical follow-up, MR reduction was sustained and there were significant reductions of pulmonary pressure (systolic pulmonary artery pressure 52 vs. 42 mmHg, p < 0.001), and tricuspid regurgitation severity (p = 0.013). Heart failure symptoms improved significantly (73% in NYHA class I/II, p < 0.001). Procedural success rate according to MVARC criteria was 80% and was not different in patients treated for an off-label indication (74% vs. 81% for off- vs. on-label, p = 0.41). CONCLUSION In a real-world patient population, TMVI has a high technical and procedural success rate with efficient and durable MR reduction and symptomatic improvement

Gammapy: A Python package for gamma-ray astronomy

In this article, we present Gammapy, an open-source Python package for the analysis of astronomical $\gamma$-ray data, and illustrate the functionalities of its first long-term-support release, version 1.0. Built on the modern Python scientific ecosystem, Gammapy provides a uniform platform for reducing and modeling data from different $\gamma$-ray instruments for many analysis scenarios. Gammapy complies with several well-established data conventions in high-energy astrophysics, providing serialized data products that are interoperable with other software packages. Starting from event lists and instrument response functions, Gammapy provides functionalities to reduce these data by binning them in energy and sky coordinates. Several techniques for background estimation are implemented in the package to handle the residual hadronic background affecting $\gamma$-ray instruments. After the data are binned, the flux and morphology of one or more $\gamma$-ray sources can be estimated using Poisson maximum likelihood fitting and assuming a variety of spectral, temporal, and spatial models. Estimation of flux points, likelihood profiles, and light curves is also supported. After describing the structure of the package, we show, using publicly available $\gamma$-ray data, the capabilities of Gammapy in multiple traditional and novel $\gamma$-ray analysis scenarios, such as spectral and spectro-morphological modeling and estimations of a spectral energy distribution and a light curve. Its flexibility and power are displayed in a final multi-instrument example, where datasets from different instruments, at different stages of data reduction, are simultaneously fitted with an astrophysical flux model.Comment: 26 pages, 16 figure

Human Practice. Digital Ecologies. Our Future. : 14. Internationale Tagung Wirtschaftsinformatik (WI 2019) : Tagungsband

Erschienen bei: universi - Universitätsverlag Siegen. - ISBN: 978-3-96182-063-4Aus dem Inhalt: Track 1: Produktion & Cyber-Physische Systeme Requirements and a Meta Model for Exchanging Additive Manufacturing Capacities Service Systems, Smart Service Systems and Cyber- Physical Systems—What’s the difference? Towards a Unified Terminology Developing an Industrial IoT Platform – Trade-off between Horizontal and Vertical Approaches Machine Learning und Complex Event Processing: Effiziente Echtzeitauswertung am Beispiel Smart Factory Sensor retrofit for a coffee machine as condition monitoring and predictive maintenance use case Stakeholder-Analyse zum Einsatz IIoT-basierter Frischeinformationen in der Lebensmittelindustrie Towards a Framework for Predictive Maintenance Strategies in Mechanical Engineering - A Method-Oriented Literature Analysis Development of a matching platform for the requirement-oriented selection of cyber physical systems for SMEs Track 2: Logistic Analytics An Empirical Study of Customers’ Behavioral Intention to Use Ridepooling Services – An Extension of the Technology Acceptance Model Modeling Delay Propagation and Transmission in Railway Networks What is the impact of company specific adjustments on the acceptance and diffusion of logistic standards? Robust Route Planning in Intermodal Urban Traffic Track 3: Unternehmensmodellierung & Informationssystemgestaltung (Enterprise Modelling & Information Systems Design) Work System Modeling Method with Different Levels of Specificity and Rigor for Different Stakeholder Purposes Resolving Inconsistencies in Declarative Process Models based on Culpability Measurement Strategic Analysis in the Realm of Enterprise Modeling – On the Example of Blockchain-Based Initiatives for the Electricity Sector Zwischenbetriebliche Integration in der Möbelbranche: Konfigurationen und Einflussfaktoren Novices’ Quality Perceptions and the Acceptance of Process Modeling Grammars Entwicklung einer Definition für Social Business Objects (SBO) zur Modellierung von Unternehmensinformationen Designing a Reference Model for Digital Product Configurators Terminology for Evolving Design Artifacts Business Role-Object Specification: A Language for Behavior-aware Structural Modeling of Business Objects Generating Smart Glasses-based Information Systems with BPMN4SGA: A BPMN Extension for Smart Glasses Applications Using Blockchain in Peer-to-Peer Carsharing to Build Trust in the Sharing Economy Testing in Big Data: An Architecture Pattern for a Development Environment for Innovative, Integrated and Robust Applications Track 4: Lern- und Wissensmanagement (e-Learning and Knowledge Management) eGovernment Competences revisited – A Literature Review on necessary Competences in a Digitalized Public Sector Say Hello to Your New Automated Tutor – A Structured Literature Review on Pedagogical Conversational Agents Teaching the Digital Transformation of Business Processes: Design of a Simulation Game for Information Systems Education Conceptualizing Immersion for Individual Learning in Virtual Reality Designing a Flipped Classroom Course – a Process Model The Influence of Risk-Taking on Knowledge Exchange and Combination Gamified Feedback durch Avatare im Mobile Learning Alexa, Can You Help Me Solve That Problem? - Understanding the Value of Smart Personal Assistants as Tutors for Complex Problem Tasks Track 5: Data Science & Business Analytics Matching with Bundle Preferences: Tradeoff between Fairness and Truthfulness Applied image recognition: guidelines for using deep learning models in practice Yield Prognosis for the Agrarian Management of Vineyards using Deep Learning for Object Counting Reading Between the Lines of Qualitative Data – How to Detect Hidden Structure Based on Codes Online Auctions with Dual-Threshold Algorithms: An Experimental Study and Practical Evaluation Design Features of Non-Financial Reward Programs for Online Reviews: Evaluation based on Google Maps Data Topic Embeddings – A New Approach to Classify Very Short Documents Based on Predefined Topics Leveraging Unstructured Image Data for Product Quality Improvement Decision Support for Real Estate Investors: Improving Real Estate Valuation with 3D City Models and Points of Interest Knowledge Discovery from CVs: A Topic Modeling Procedure Online Product Descriptions – Boost for your Sales? Entscheidungsunterstützung durch historienbasierte Dienstreihenfolgeplanung mit Pattern A Semi-Automated Approach for Generating Online Review Templates Machine Learning goes Measure Management: Leveraging Anomaly Detection and Parts Search to Improve Product-Cost Optimization Bedeutung von Predictive Analytics für den theoretischen Erkenntnisgewinn in der IS-Forschung Track 6: Digitale Transformation und Dienstleistungen Heuristic Theorizing in Software Development: Deriving Design Principles for Smart Glasses-based Systems Mirroring E-service for Brick and Mortar Retail: An Assessment and Survey Taxonomy of Digital Platforms: A Platform Architecture Perspective Value of Star Players in the Digital Age Local Shopping Platforms – Harnessing Locational Advantages for the Digital Transformation of Local Retail Outlets: A Content Analysis A Socio-Technical Approach to Manage Analytics-as-a-Service – Results of an Action Design Research Project Characterizing Approaches to Digital Transformation: Development of a Taxonomy of Digital Units Expectations vs. Reality – Benefits of Smart Services in the Field of Tension between Industry and Science Innovation Networks and Digital Innovation: How Organizations Use Innovation Networks in a Digitized Environment Characterising Social Reading Platforms— A Taxonomy-Based Approach to Structure the Field Less Complex than Expected – What Really Drives IT Consulting Value Modularity Canvas – A Framework for Visualizing Potentials of Service Modularity Towards a Conceptualization of Capabilities for Innovating Business Models in the Industrial Internet of Things A Taxonomy of Barriers to Digital Transformation Ambidexterity in Service Innovation Research: A Systematic Literature Review Design and success factors of an online solution for cross-pillar pension information Track 7: IT-Management und -Strategie A Frugal Support Structure for New Software Implementations in SMEs How to Structure a Company-wide Adoption of Big Data Analytics The Changing Roles of Innovation Actors and Organizational Antecedents in the Digital Age Bewertung des Kundennutzens von Chatbots für den Einsatz im Servicedesk Understanding the Benefits of Agile Software Development in Regulated Environments Are Employees Following the Rules? On the Effectiveness of IT Consumerization Policies Agile and Attached: The Impact of Agile Practices on Agile Team Members’ Affective Organisational Commitment The Complexity Trap – Limits of IT Flexibility for Supporting Organizational Agility in Decentralized Organizations Platform Openness: A Systematic Literature Review and Avenues for Future Research Competence, Fashion and the Case of Blockchain The Digital Platform Otto.de: A Case Study of Growth, Complexity, and Generativity Track 8: eHealth & alternde Gesellschaft Security and Privacy of Personal Health Records in Cloud Computing Environments – An Experimental Exploration of the Impact of Storage Solutions and Data Breaches Patientenintegration durch Pfadsysteme Digitalisierung in der Stressprävention – eine qualitative Interviewstudie zu Nutzenpotenzialen User Dynamics in Mental Health Forums – A Sentiment Analysis Perspective Intent and the Use of Wearables in the Workplace – A Model Development Understanding Patient Pathways in the Context of Integrated Health Care Services - Implications from a Scoping Review Understanding the Habitual Use of Wearable Activity Trackers On the Fit in Fitness Apps: Studying the Interaction of Motivational Affordances and Users’ Goal Orientations in Affecting the Benefits Gained Gamification in Health Behavior Change Support Systems - A Synthesis of Unintended Side Effects Investigating the Influence of Information Incongruity on Trust-Relations within Trilateral Healthcare Settings Track 9: Krisen- und Kontinuitätsmanagement Potentiale von IKT beim Ausfall kritischer Infrastrukturen: Erwartungen, Informationsgewinnung und Mediennutzung der Zivilbevölkerung in Deutschland Fake News Perception in Germany: A Representative Study of People’s Attitudes and Approaches to Counteract Disinformation Analyzing the Potential of Graphical Building Information for Fire Emergency Responses: Findings from a Controlled Experiment Track 10: Human-Computer Interaction Towards a Taxonomy of Platforms for Conversational Agent Design Measuring Service Encounter Satisfaction with Customer Service Chatbots using Sentiment Analysis Self-Tracking and Gamification: Analyzing the Interplay of Motivations, Usage and Motivation Fulfillment Erfolgsfaktoren von Augmented-Reality-Applikationen: Analyse von Nutzerrezensionen mit dem Review-Mining-Verfahren Designing Dynamic Decision Support for Electronic Requirements Negotiations Who is Stressed by Using ICTs? A Qualitative Comparison Analysis with the Big Five Personality Traits to Understand Technostress Walking the Middle Path: How Medium Trade-Off Exposure Leads to Higher Consumer Satisfaction in Recommender Agents Theory-Based Affordances of Utilitarian, Hedonic and Dual-Purposed Technologies: A Literature Review Eliciting Customer Preferences for Shopping Companion Apps: A Service Quality Approach The Role of Early User Participation in Discovering Software – A Case Study from the Context of Smart Glasses The Fluidity of the Self-Concept as a Framework to Explain the Motivation to Play Video Games Heart over Heels? An Empirical Analysis of the Relationship between Emotions and Review Helpfulness for Experience and Credence Goods Track 11: Information Security and Information Privacy Unfolding Concerns about Augmented Reality Technologies: A Qualitative Analysis of User Perceptions To (Psychologically) Own Data is to Protect Data: How Psychological Ownership Determines Protective Behavior in a Work and Private Context Understanding Data Protection Regulations from a Data Management Perspective: A Capability-Based Approach to EU-GDPR On the Difficulties of Incentivizing Online Privacy through Transparency: A Qualitative Survey of the German Health Insurance Market What is Your Selfie Worth? A Field Study on Individuals’ Valuation of Personal Data Justification of Mass Surveillance: A Quantitative Study An Exploratory Study of Risk Perception for Data Disclosure to a Network of Firms Track 12: Umweltinformatik und nachhaltiges Wirtschaften Kommunikationsfäden im Nadelöhr – Fachliche Prozessmodellierung der Nachhaltigkeitskommunikation am Kapitalmarkt Potentiale und Herausforderungen der Materialflusskostenrechnung Computing Incentives for User-Based Relocation in Carsharing Sustainability’s Coming Home: Preliminary Design Principles for the Sustainable Smart District Substitution of hazardous chemical substances using Deep Learning and t-SNE A Hierarchy of DSMLs in Support of Product Life-Cycle Assessment A Survey of Smart Energy Services for Private Households Door-to-Door Mobility Integrators as Keystone Organizations of Smart Ecosystems: Resources and Value Co-Creation – A Literature Review Ein Entscheidungsunterstützungssystem zur ökonomischen Bewertung von Mieterstrom auf Basis der Clusteranalyse Discovering Blockchain for Sustainable Product-Service Systems to enhance the Circular Economy Digitale Rückverfolgbarkeit von Lebensmitteln: Eine verbraucherinformatische Studie Umweltbewusstsein durch audiovisuelles Content Marketing? Eine experimentelle Untersuchung zur Konsumentenbewertung nachhaltiger Smartphones Towards Predictive Energy Management in Information Systems: A Research Proposal A Web Browser-Based Application for Processing and Analyzing Material Flow Models using the MFCA Methodology Track 13: Digital Work - Social, mobile, smart On Conversational Agents in Information Systems Research: Analyzing the Past to Guide Future Work The Potential of Augmented Reality for Improving Occupational First Aid Prevent a Vicious Circle! The Role of Organizational IT-Capability in Attracting IT-affine Applicants Good, Bad, or Both? Conceptualization and Measurement of Ambivalent User Attitudes Towards AI A Case Study on Cross-Hierarchical Communication in Digital Work Environments ‘Show Me Your People Skills’ - Employing CEO Branding for Corporate Reputation Management in Social Media A Multiorganisational Study of the Drivers and Barriers of Enterprise Collaboration Systems-Enabled Change The More the Merrier? The Effect of Size of Core Team Subgroups on Success of Open Source Projects The Impact of Anthropomorphic and Functional Chatbot Design Features in Enterprise Collaboration Systems on User Acceptance Digital Feedback for Digital Work? Affordances and Constraints of a Feedback App at InsurCorp The Effect of Marker-less Augmented Reality on Task and Learning Performance Antecedents for Cyberloafing – A Literature Review Internal Crowd Work as a Source of Empowerment - An Empirical Analysis of the Perception of Employees in a Crowdtesting Project Track 14: Geschäftsmodelle und digitales Unternehmertum Dividing the ICO Jungle: Extracting and Evaluating Design Archetypes Capturing Value from Data: Exploring Factors Influencing Revenue Model Design for Data-Driven Services Understanding the Role of Data for Innovating Business Models: A System Dynamics Perspective Business Model Innovation and Stakeholder: Exploring Mechanisms and Outcomes of Value Creation and Destruction Business Models for Internet of Things Platforms: Empirical Development of a Taxonomy and Archetypes Revitalizing established Industrial Companies: State of the Art and Success Principles of Digital Corporate Incubators When 1+1 is Greater than 2: Concurrence of Additional Digital and Established Business Models within Companies Special Track 1: Student Track Investigating Personalized Price Discrimination of Textile-, Electronics- and General Stores in German Online Retail From Facets to a Universal Definition – An Analysis of IoT Usage in Retail Is the Technostress Creators Inventory Still an Up-To-Date Measurement Instrument? Results of a Large-Scale Interview Study Application of Media Synchronicity Theory to Creative Tasks in Virtual Teams Using the Example of Design Thinking TrustyTweet: An Indicator-based Browser-Plugin to Assist Users in Dealing with Fake News on Twitter Application of Process Mining Techniques to Support Maintenance-Related Objectives How Voice Can Change Customer Satisfaction: A Comparative Analysis between E-Commerce and Voice Commerce Business Process Compliance and Blockchain: How Does the Ethereum Blockchain Address Challenges of Business Process Compliance? Improving Business Model Configuration through a Question-based Approach The Influence of Situational Factors and Gamification on Intrinsic Motivation and Learning Evaluation von ITSM-Tools für Integration und Management von Cloud-Diensten am Beispiel von ServiceNow How Software Promotes the Integration of Sustainability in Business Process Management Criteria Catalog for Industrial IoT Platforms from the Perspective of the Machine Tool Industry Special Track 3: Demos & Prototyping Privacy-friendly User Location Tracking with Smart Devices: The BeaT Prototype Application-oriented robotics in nursing homes Augmented Reality for Set-up Processe Mixed Reality for supporting Remote-Meetings Gamification zur Motivationssteigerung von Werkern bei der Betriebsdatenerfassung Automatically Extracting and Analyzing Customer Needs from Twitter: A “Needmining” Prototype GaNEsHA: Opportunities for Sustainable Transportation in Smart Cities TUCANA: A platform for using local processing power of edge devices for building data-driven services Demonstrator zur Beschreibung und Visualisierung einer kritischen Infrastruktur Entwicklung einer alltagsnahen persuasiven App zur Bewegungsmotivation für ältere Nutzerinnen und Nutzer A browser-based modeling tool for studying the learning of conceptual modeling based on a multi-modal data collection approach Exergames & Dementia: An interactive System for People with Dementia and their Care-Network Workshops Workshop Ethics and Morality in Business Informatics (Workshop Ethik und Moral in der Wirtschaftsinformatik – EMoWI’19) Model-Based Compliance in Information Systems - Foundations, Case Description and Data Set of the MobIS-Challenge for Students and Doctoral Candidates Report of the Workshop on Concepts and Methods of Identifying Digital Potentials in Information Management Control of Systemic Risks in Global Networks - A Grand Challenge to Information Systems Research Die Mitarbeiter von morgen - Kompetenzen künftiger Mitarbeiter im Bereich Business Analytics Digitaler Konsum: Herausforderungen und Chancen der Verbraucherinformati

strategies for excellent initial and long-term results

Die kathetergestützte Aortenklappenimplantation (TAVI) hat sich als eine echte Alternative zum chirurgischen Aortenklappenersatz etabliert. Bereits heute sind mit der Variation an verfügbaren Zugangswegen und Prothesentypen technisch nahezu alle Patienten mit hochgradiger und symptomatischer Aortenklappenstenose mit diesem neuen Verfahren therapierbar. Unsichere Langzeitergebnissen, TAVI-spezifische Komplikationen und Imperfektionen des Implantationsergebnisses der Prothese sind Nachteile, die gegen eine generelle Anwendung, insbesondere bei jungen Patienten mit niedrigem Risikoprofil nach derzeitigem Kenntnisstand sprechen. Das Streben nach dem Idealziel, die erkrankte Aortenklappe vollständig und ohne operatives Trauma therapieren zu können, ist die treibende Kraft für die zu erwartende weitere Ausdehnung des Indikationsspektrums. Dieser Herausforderung müssen sich die moderne Kardiochirurgie und Kardiologie stellen, was zweifelsohne beide Disziplinen grundlegend verändern und stärker aneinander binden wird. Insbesondere bei Patienten mit einem hohen chirurgischen Risiko erlaubt das TAVI-Verfahren eine sichere Elimination von Aortenklappenstenose, wobei unsere Studien an einer großen Patientenkohorte, die mit einer einheitlichen Strategie behandelt wurde, eine erhebliche Reduktion der erwarteten Sterblichkeit aufzeigen. Mit Anwendung eines strukturierten Trainingsprogramms war es möglich, auch die technisch komplexere TA-Implantationstechnik ohne nachteilige Effekte in der Initialphase der Lernkurve zu etablieren und reproduzierbar eine sehr niedrige periprozedurale Letalität zu erzielen. In der statistischen Analyse konnten wir drei wesentliche Gründe für Sterblichkeit nach TAVI identifizieren: (1) Komorbidität, (2) fortgeschrittene Stadien der Herzinsuffizienz und (3) periprozedurale Komplikationen. Nach Elimination der Aortenklappenstenose versterben die Patienten an nichtkardialen Begleiterkrankungen (wie Niereninsuffizienz oder chronischen Lungenerkrankungen) und an kardialen Begleiterkrankung, die nicht unbedingt Folge der Aortenklappenstenose sind (wie koronare Herzerkrankung oder Vorhofflimmern). Klassische, in der Kardiochirurgie angewendete Modelle der arithmetischen Risikobestimmung (additiver und logistischer EuroSCORE, EuroSCORE II, STS-PROM) sind starke Determinanten der Sterbewahrscheinlichkeit auch nach TAVI-Prozeduren wenngleich sie hier keine Absolutwerte der Sterbewahrscheinlichkeit ausdrücken. Darüber hinaus sind das Stadium der Herzinsuffizienz, gemessen in NYHA-Stadium oder im N-terminalen-pro-Brain-natriuretischen-Peptid-Spiegel, ausgedrückt in dem Grad der Verminderung der linksventrikulären Funktion oder einer akuten Dekompensation bis hin zum kardiogenen Schock prädiktiv für postprozedurale Letalität, was die Bedeutsamkeit einer frühzeitigen Versorgung der Aortenklappenstenose unterstreicht. Neben diesen patientenintrinsischen Faktoren sind prozedurassoziierte extrinsische Faktoren insbesondere für die Frühsterblichkeit bedeutsam, wobei dieser Einfluss auch im Langzeitverlauf erkennbar bleibt. Mit TAVI zeichnen sich bereits heute neue Behandlungshorizonte ab. Insbesondere werden hiermit Patienten therapierbar, die bei sehr schlechter linksventrikulärer Funktion oder im kardiogenen Schock davon profitieren, dass TAVI eine vollständige Elimination der Aortenklappenstenose ohne zusätzliches myokardiales Trauma ermöglicht. Eine rasche Restitution der Myokardfunktion konnten wir in diesen Patientengruppen nachweisen. Zudem sehen wir die Möglichkeit, TAVI mit klassischen Methoden der interventionellen Kardiologie und klassischen Kardiochirurgie zu kombinieren und somit wesentlich schonendere, individuelle Therapiekonzepte insbesondere für die Gruppe der Patienten mit kritischen Risiken verfügbar zu haben. Die wesentliche Prämisse für ein exzellentes Langzeitresultat ist in der Erzielung eines perfekten Implantationsergebnisses zu sehen. Das Vermeiden von Leckagen ist aufgrund der nachgewiesenen langfristig erhöhten Letalität bedeutsam; die Prävention von Anulusrupturen ist für die instantane Sicherheit des TAVI- Verfahrens unabdingbar. Es lassen sich starke morphologische Substrate für das Risiko der postprozeduralen Leckage aus der prä- und intraprozeduralen Diagnostik ableiten, deren Kenntnis für den Therapieerfolg entscheidend ist. Unsere Analysen konnten im Verkalkungsgrad der Landungszone und insbesondere im Nachweis subanulärer Kalkformationen, einer asymmetrischen Kalziumdistribution oder einer starken Exzentrizität der virtuellen Anulusellipse bestimmende Einflussgrößen der postprozeduralen Regurgitation offenbaren. Zudem hat die Auswahl der Prothesengröße und der Grad der Überdimensionierung Einfluss auf das Risiko für Leckage und Ruptur. Unsere Studien belegen, dass mit einer präzisen Wahl der Implantationshöhe durch eine verbesserten Implantationstechnik, einer multimodalen Vermessung der Prothesenlandungszone, deren Morphologie und Verkalkungsgrad und dies verbunden mit dem Anspruch, relevante Insuffizienzgrade nicht zu akzeptieren, mittel- oder schwergradige Protheseninsuffizienzen komplett eliminiert werden können. Geringgradige und triviale Insuffizienzgrade haben in unseren Analysen keinen nachteiligen Einfluss auf das langfristige Überleben nach TAVI. Die wesentliche Voraussetzung zur Erzielung eines optimalen Implantationsergebnisses ist in der Erfahrung des interdisziplinären Implantationsteams zu sehen, welches in der Lage ist, jegliche, aber insbesondere schwerwiegende Komplikationen sofort zu erkennen, diese interventionell und chirurgisch behandeln zu können und insbesondere das Risiko für deren Entstehung in der präprozeduralen Evaluation des Patienten abzuschätzen und mit Adaptation der Implantationsstrategie zu vermeiden. Im optimalen Initialergebnis sehen wir den Schlüssel für das langfristig exzellente Resultat nach TAVI-Eingriffen.Transcatheter aortic valve implantation (TAVI) was introduced into clinical practice as a true alternative to surgical aortic valve replacement. Today, with the different established access sites and the variety of TAVI devices available, almost all patients with high-grade and symptomatic aortic valve stenosis can be treated by applying this new hybrid technique. The absence of long-term results, TAVI-specific procedural complications and imperfections in terms of the implantation result are known limitations. Based on the current scientific knowledge, TAVI should not be applied as a first-line strategy, especially in younger patients with a low surgical risk profile. The ultimate goal of eliminating aortic valve stenosis without any surgical trauma is the driving force for methodological progress as a prerequisite to expand the indication beyond the limits defined in current guidelines. Furthermore, transcatheter treatment of heart valve disease represents a paradigm shift in contemporary heart medicine. It indicates the challenging process of closer interaction and prospective blending between cardiac surgery and cardiology. In patients with a high surgical risk profile, in particular, TAVI offers a safe therapeutic option to eliminate aortic valve stenosis. Based on the dataset of a large cohort treated with a consistent strategy, our analyses demonstrate a marked reduction in predicted mortality in high-risk patients. By applying a structured training program, even the more complex transapical method has been established at our institution without any disadvantages and with a reproducible very low mortality rate even during the initial phase of our institutional learning curve. In our studies, three main factors of mortality after TAVI were identified: (1) the patient’s comorbidity profile, (2) the presence of advanced stages of heart failure, and (3) the occurrence of periprocedural complications. After elimination of aortic valve stenosis, patients die from non-cardiac comorbidity (such as renal failure or chronic lung diseases) or cardiac comorbidity not directly in consequence of aortic valve disease (coronary artery disease or chronic atrial fibrillation). Classic arithmetic risk estimators in cardiac surgery (additive/logistic EuroSCORE, EuroSCORE II, and STS PROM score) are strong determinants of prognostic probability but overestimate mortality in absolute values after TAVI procedures. Furthermore, the stage of heart failure, as expressed in NYHA functional class, in NT-pro-BNP-level and in the manifestation of acute decompensation up to profound cardiogenic shock, was found to be predictive for follow-up mortality. This emphasizes the priority of treating severe aortic valve stenosis at early stages. In addition to intrinsic factors, extrinsic procedural factors influence early and long-term mortality. TAVI opens up the possibility to explore new horizons. In patients with cardiogenic shock and very poor left ventricular performance, TAVI offers complete elimination of aortic valve stenosis without the additional trauma of cardioplegic arrest. Furthermore, we observed instant myocardial recovery after treatment in these patients. For patients with complex cardiac diseases and extreme risks, more gentle concepts combining TAVI and other classical therapeutic strategies from cardiac surgery or interventional cardiology have emerged. Achieving a perfect result during the implantation process is the prerequisite to reaching an excellent long-term outcome. It is mandatory to avoid paravalvular leakage, known to be associated with increased follow-up mortality. The prevention of annular rupture is also essential for the safety of TAVI procedures. There are strong predictors in terms of device landing zone morphology for paravalvular leakage, the “Achilles’ heel” of TAVI. These risk factors may be assessed by preprocedural and intraprocedural multimodal diagnostic tools. Device landing zone calcification in general, but most importantly in the subvalvular outflow tract, asymmetric cusp calcification and eccentricity of the aortic annulus were found to be predictive for regurgitation after valve deployment in our multivariable analyses. Especially in borderline morphologies, choosing the appropriate prosthesis size and the grade of oversizing may be a dilemma of navigating between Scylla and Charybdis to avoid leakage and annular rupture. Our studies indicate the relevance of precise definition of the implantation height based on comprehensive multimodal evaluation of the device landing zone anatomy and calcification. Adopting the “surgical way of thinking”, moderate or severe regurgitation should be abolished in TAVI procedures. Trace or mild postprocedural leakage was found to be without adverse effects on long-term survival in our studies. The key factor in achieving optimal initial results is the experience of the implanting team. It is emphasized that all team members should be aware of severe complications, able to recognize individual risk factors, flexible to adapt to the best implantation strategy and capable of treating all complications by applying interventional and surgical techniques. Initial perfection is the secret of success to achieve excellent long-term results after TAVI procedures

Die vegetative Kontrolle der Herzfrequenz und ihre Koordination mit dem respiratorischen System untersucht im Schlafen und Wachen nnerhalb der Pubertaet: Eine zeitreihenanalytische Studie

Die Atmung und das Herz-Kreislauf-System interagieren als zwei in Reihe angeordnete funktionelle Einheiten. Die gleichsinnige Kontrolle beider Systeme bildet die Grundlage homöostatischer Bedingungen im Organismus. Neurophysiologische Studien geben Hinweise auf die Existenz eines gemeinsamen neuronalen kardiorespiratorischen Netzwerkes, welches im ventrolateralen Teil der Medulla oblongata gelegen ist. Da zentrale Mechanismen der Regulation einer direkten Untersuchung nicht zugänglich sind, erweisen sich die linearen und nichtlinearen Verfahren der Zeitreihenanalyse als hilfreich, um Erkenntnisse von der Arbeitsweise des kardiorespiratorischen Kontrollsystems zu gewinnen. Grundlage der Studie bildet eine Datenbank polygraphischer Messungen (einschließlich EKG, thorakales und abdominales Respirogramm, Elektrookulogramm und Aktogramm), die an 42 gesunden Kindern, 11 Mädchen und 31 Knaben im Alter von 12 bis 15 Jahren erhoben wurde. Die Messungen erfolgten über 24 Stunden hinweg, während folgender Vigilanzstadien: ruhiger Wachzustand, REM- und nonREM-Schlaf. Die spektralen Charakteristika der Herzfrequenzvariabilität wurden berechnet, um die sympatho-vagale Einflußnahme auf den Nodus sinusoidalis kennzeichnen zu können. Die lineare Intensität der kardiorespiratorischen Beziehung wurde aus den Kohärenzspektren abgeleitet. Um nichtlineares Verhalten erfassen zu können, wurden der größte Lyapunov-Exponent und die Korrelationsdimension der Herzfrequenz, sowie die Korrelationsdimension des Atemsignals bestimmt. Die Analyse der Herzfrequenzvariabilität ergab für die Gesamtleistung die höchsten Werte innerhalb der REM-Phasen, im Wachzustand lagen diese deutlich niedriger und während des nonREM-Schlafes waren sie am kleinsten. Dieses Verhalten wurde im wesentlichen bestimmt von Änderungen der Spektralleistung im niederfrequenten Bereich. Die Komplexität der Herzfrequenz, die sich mit der Korrelationsdimension schätzen läßt, zeigte eine deutliche Abnahme im Schlaf. Dagegen erwies sich der Lyapunov-Exponent als weniger sensitiv bezüglich der Vigilanz. Die kardiorespiratorische Kohärenz ließ eine strenge Abhängigkeit vom Vigilanzstadium erkennen mit hohen Werten im nonREM-Schlaf und dem Minimum innerhalb der REM-Phasen. Im Gegensatz zur Komplexität der Herzfrequenz erreichte die Komplexität der Atmung die niedrigsten Werte in den REM-Phasen. Mit den Ergebnissen der Spektralanalyse lassen sich vigilanzstadienspezifische Einstellungen in der vegetativen Kontrolle der Herzfrequenz abgrenzen. Die nichtlinearen Verfahren offenbaren niederdimensionale deterministisch-chaotische Strukturen der Herzfrequenz. Die Zahl unabhängiger Mechanismen, die Anteil an der kardiorespiratorischen Regulation haben, ist im Wachzustand am größten. Diese Änderungen lassen das Gesamtsystem in Abhängigkeit von der Vigilanz verschiedene Arbeitspunkte einnehmen.Breathing and blood flow interact as two, in series coupled units. To adapt heart beat and oxygen supply, a common coordination is required. Concluded from neurophysiological investigations, there is evidence for the existence of one cardiorespiratory network located in the ventrolateral part of the medulla. Since the physiological mechanisms inside the complex regulatory network are not readily accessible, linear and non-linear methods of time series analysis are a useful approach to investigate cardiorespiratory control. To study normal regulation, 42 healthy children, 11 girls and 31 boys (12-15 yr.), were investigated throughout 24 hours under different states of vigilance: wakefulness at rest, REM, and nonREM-sleep. All participants underwent polygraphic measurements, including ECG, thoracic and abdominal respirograms, electrooculogram, and actogram. To estimate the sympatho-vagal drive to the sinus node, the parameters of heart rate power spectra were calculated. The linear intensity of cardiorespiratory coupling was concluded from the coherence spectra. As to non-linear properties of heart rate, the largest Lyapunov exponents as well as the correlation dimension were determined. Similarly, the correlation dimension of the respiratory signals was evaluated. The total power of the heart rate spectrum was found to be greatest during REM, it decreased during wakefulness and was low in nonREM-sleep. These variations are mainly accounted for by low frequency power. The "complexity" of heart rate, as indicated by the correlation dimension, is diminished during sleep phases, whereas the Lyapunov exponents are less affected. The cardiorespiratory coherence is strongly modulated by vigilance with an increase during nonREM and lowest values during REM. The complexity of respiration was also affected by vigilance. A different behavior of heart rate complexity was found during REM-phases. Concluded from spectral analysis, a specific setting of autonomic heart rate regulation for each vigilance stage can be suggested. A low dimensional deterministic chaos is present in heart rate time series. More independent control loops were found to be active during wakefulness. Revealed by parameters of the non-linear dynamics, different stages of vigilance determine different operating points in the cardiorespiratory coordination

Which patients with aortic stenosis should be referred to surgery rather than transcatheter aortic valve implantation?

Transcatheter aortic valve implantation (TAVI) has matured into a standard treatment option for patients with severe symptomatic aortic valve stenosis (AS) across the whole spectrum of risk. The advances in the interventional treatment of AS raise the question of which patients with severe AS should be referred to surgery. The myriad of clinical permutations does not allow providing a single, uniform treatment strategy. Rather, the advent of TAVI along with established surgical aortic valve replacement (SAVR) fundamentally enforces the role of the multidisciplinary heart team for decision-making recommending the best individual choice of the two options based on a thorough review of clinical and anatomical factors as well as lifetime management considerations. Involvement of the informed patient expressing treatment preferences is a key for a shared decision-making process. Herein, we provide an in-depth review of evidence informing the decision-making process between TAVI and SAVR and key elements for treatment selection. Special attention is given to the populations that have been excluded from randomized clinical trials, and also lifetime management strategies of patients with severe AS are proposed