43 results on '"Kroener, Axel"'
Search Results
2. Classification with Runge-Kutta networks and feature space augmentation
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Giesecke, Elisa and Kröner, Axel
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Computer Science - Machine Learning ,Mathematics - Dynamical Systems ,65L06, 68T07 - Abstract
In this paper we combine an approach based on Runge-Kutta Nets considered in [Benning et al., J. Comput. Dynamics, 9, 2019] and a technique on augmenting the input space in [Dupont et al., NeurIPS, 2019] to obtain network architectures which show a better numerical performance for deep neural networks in point and image classification problems. The approach is illustrated with several examples implemented in PyTorch.
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- 2021
3. Existence, uniqueness, and stabilization results for parabolic variational inequalities
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Kröner, Axel, Rautenberg, Carlos N., and Rodrigues, Sérgio S.
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Mathematics - Optimization and Control ,Mathematics - Analysis of PDEs ,35K85, 93D15 - Abstract
In this paper we consider feedback stabilization for parabolic variational inequalities of obstacle type with time and space depending reaction and convection coefficients and show exponential stabilization to nonstationary trajectories. Based on a Moreau-Yosida approximation, a feedback operator is established using a finite (and uniform in the approximation index) number of actuators leading to exponential decay of given rate of the state variable. Several numerical examples are presented addressing smooth and nonsmooth obstacle functions., Comment: 55 subfigures
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- 2021
4. A priori error estimates for finite element approximations of regularized level set flows in higher norms
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Kröner, Axel and Kröner, Heiko
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Mathematics - Numerical Analysis ,35J66, 35J93, 65N15, 65N30 - Abstract
This paper proves error estimates for $H^2$ conforming finite elements for equations which model the flow of surfaces by different powers of the mean curvature (this includes mean curvature flow). for an adapted scheme originally proposed in [17] for the inverse mean curvature flow. The scheme is based on a known regularization procedure and produces different kinds of errors, a regularization error, a finite element discretization error for the regularized problems and a full error. While in the literature and own previous work different aspects of the aforementioned error types are treated, here, we solely and for the first time focus on the finite element discretization error in the $W^{2,\mu}$ norm for the regularized equation analyzing also the dependencies from the regularization parameter.
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- 2020
5. State constrained control-affine parabolic problems II: Second order sufficient optimality conditions
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Aronna, M. Soledad, Bonnans, J. -Frédéric, and Kröner, Axel
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Mathematics - Optimization and Control ,49J20, 49K20, 35J05, 35K58, 93C20 - Abstract
In this paper we consider an optimal control problem governed by a semilinear heat equation with bilinear control-state terms and subject to control and state constraints. The state constraints are of integral type, the integral being with respect to the space variable. The control is multidimensional. The cost functional is of a tracking type and contains a linear term in the control variables. We derive second order sufficient conditions relying on the Goh transform. The appendix provides an example illustrating the applicability of our results., Comment: This is the second part of a work on optimality conditions for a control problem of a semilinear heat equation. More precisely, the full version, available arXiv:1906.00237, has been divided in two, resulting in arXiv:1906.00237v2 (that corresponds to Part I) and the current manuscript (which is Part II)
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- 2019
6. State-constrained control-affine parabolic problems I: first and second order necessary optimality conditions
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Aronna, M. Soledad, Bonnans, J. Frédéric, and Kröner, Axel
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Mathematics - Optimization and Control ,49J20, 49K20, 35J05, 35K58, 93C20 - Abstract
In this paper we consider an optimal control problem governed by a semilinear heat equation with bilinear control-state terms and subject to control and state constraints. The state constraints are of integral type, the integral being with respect to the space variable. The control is multidimensional. The cost functional is of a tracking type and contains a linear term in the control variables. We derive second order necessary conditions relying on the concept of alternative costates and quasi-radial critical directions. The appendix provides an example illustrating the applicability of our results., Comment: This is the first part of a work on optimality conditions for a control problem of a semilinear heat equation. More precisely, the full version, available at arXiv:1906.00237v1, has been divided in two, resulting in the current manuscript (that corresponds to Part I) and arXiv:1909.05056 (which is Part II)
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- 2019
7. Galerkin approximations for the optimal control of nonlinear delay differential equations
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Chekroun, Mickaël D., Kröner, Axel, and Liu, Honghu
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Mathematics - Optimization and Control ,Mathematics - Dynamical Systems - Abstract
Optimal control problems of nonlinear delay differential equations (DDEs) are considered for which we propose a general Galerkin approximation scheme built from Koornwinder polynomials. Error estimates for the resulting Galerkin-Koornwinder approximations to the optimal control and the value function, are derived for a broad class of cost functionals and nonlinear DDEs. The approach is illustrated on a delayed logistic equation set not far away from its Hopf bifurcation point in the parameter space. In this case, we show that low-dimensional controls for a standard quadratic cost functional can be efficiently computed from Galerkin-Koornwinder approximations to reduce at a nearly optimal cost the oscillation amplitude displayed by the DDE's solution. Optimal controls computed from the Pontryagin's maximum principle (PMP) and the Hamilton-Jacobi-Bellman equation (HJB) associated with the corresponding ODE systems, are shown to provide numerical solutions in good agreement. It is finally argued that the value function computed from the corresponding reduced HJB equation provides a good approximation of that obtained from the full HJB equation., Comment: 29 pages. This is a sequel of the arXiv preprint arXiv:1704.00427
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- 2017
8. Galerkin approximations of nonlinear optimal control problems in Hilbert spaces
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Chekroun, Mickaël D., Kröner, Axel, and Liu, Honghu
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Mathematics - Optimization and Control ,Mathematics - Dynamical Systems - Abstract
Nonlinear optimal control problems in Hilbert spaces are considered for which we derive approximation theorems for Galerkin approximations. Approximation theorems are available in the literature. The originality of our approach relies on the identification of a set of natural assumptions that allows us to deal with a broad class of nonlinear evolution equations and cost functionals for which we derive convergence of the value functions associated with the optimal control problem of the Galerkin approximations. This convergence result holds for a broad class of nonlinear control strategies as well. In particular, we show that the framework applies to the optimal control of semilinear heat equations posed on a general compact manifold without boundary. The framework is then shown to apply to geoengineering and mitigation of greenhouse gas emissions formulated for the first time in terms of optimal control of energy balance climate models posed on the sphere $\mathbb{S}^2$., Comment: 41 pages
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- 2017
9. A priori error estimates for finite element approximations of regularized level set flows in higher norms
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Kröner, Axel and Kröner, Heiko
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- 2022
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10. Optimal control of PDEs in a complex space setting; application to the Schr\'odinger equation
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Aronna, M. Soledad, Bonnans, Frédéric, and Kröner, Axel
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Mathematics - Optimization and Control ,49J20, 49K20, 35J10, 93C20 - Abstract
In this paper we discuss optimality conditions for abstract optimization problems over complex spaces. We then apply these results to optimal control problems with a semigroup structure. As an application we detail the case when the state equation is the Schr\"{o}dinger one, with pointwise constraints on the "bilinear" control. We derive first and second order optimality conditions and address in particular the case that the control enters the state equation and cost function linearly., Comment: arXiv admin note: text overlap with arXiv:1602.06469
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- 2016
11. Optimal control of infinite dimensional bilinear systems: Application to the heat and wave equations
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Aronna, M. Soledad, Bonnans, Frédéric, and Kröner, Axel
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Mathematics - Optimization and Control ,49K20, 49K27 - Abstract
In this paper we consider second order optimality conditions for a bilinear optimal control problem governed by a strongly continuous semigroup operator, the control entering linearly in the cost function. We derive first and second order optimality conditions, taking advantage of the Goh transform. We then apply the results to the heat and wave equations., Comment: To appear in Mathematical Programming
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- 2016
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12. Numerical approximation of level set power mean curvature flow
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Kröner, Axel, Kröner, Eva, and Kröner, Heiko
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Mathematics - Numerical Analysis ,53A10, 65L60, 35D40 - Abstract
In this paper we investigate the numerical approximation of a variant of the mean curvature flow. We consider the evolution of hypersurfaces with normal speed given by $H^k$, $k \ge 1$, where $H$ denotes the mean curvature. We use a level set formulation of this flow and discretize the regularized level set equation with finite elements. In a previous paper we proved an a priori estimate for the approximation error between the finite element solution and the solution of the original level set equation. We obtained an upper bound for this error which is polynomial in the discretization parameter and the reciprocal regularization parameter. The aim of the present paper is the numerical study of the behavior of the evolution and the numerical verification of certain convergence rates. We restrict the consideration to the case that the level set function depends on two variables, i.e. the moving hypersurfaces are curves. Furthermore, we confirm for specific initial curves and different values of $k$ that the flow improves the isoperimetrical deficit.
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- 2015
13. Local minimization algorithms for dynamic programming equations
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Kalise, Dante, Kröner, Axel, and Kunisch, Karl
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Mathematics - Optimization and Control ,Computer Science - Systems and Control ,Mathematics - Numerical Analysis - Abstract
The numerical realization of the dynamic programming principle for continuous-time optimal control leads to nonlinear Hamilton-Jacobi-Bellman equations which require the minimization of a nonlinear mapping over the set of admissible controls. This minimization is often performed by comparison over a finite number of elements of the control set. In this paper we demonstrate the importance of an accurate realization of these minimization problems and propose algorithms by which this can be achieved effectively. The considered class of equations includes nonsmooth control problems with $\ell_1$-penalization which lead to sparse controls., Comment: 27 pages, 6 figures
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- 2015
14. Axillar or Aortic Cannulation for Aortic Repair in Patients With Stanford A Dissection?
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Sabashnikov, Anton, Heinen, Stephanie, Deppe, Antje-Christin, Zeriouh, Mohamed, Weymann, Alexander, Slottosch, Ingo, Eghbalzadeh, Kaveh, Popov, Aron-Frederik, Liakopoulos, Oliver-Johannes, Rahmanian, Parwis B., Madershahian, Navid, Kroener, Axel, Choi, Yeong-Hoon, Kuhn-Régnier, Ferdinand, Simon, André R., Wahlers, Thorsten, and Wippermann, Jens
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- 2016
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15. Existence, uniqueness, and stabilization results for parabolic variational inequalities
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Kroener, Axel, primary, Rodrigues, Sergio S., additional, and Rautenberg, Carlos, additional
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- 2023
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16. Semismooth Newton Methods for an Optimal Boundary Control Problem of Wave Equations
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Kröner, Axel, Kunisch, Karl, Vexler, Boris, Diehl, Moritz, editor, Glineur, Francois, editor, Jarlebring, Elias, editor, and Michiels, Wim, editor
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- 2010
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17. Risk factors associated with in-hospital mortality for patients with ECLS due to postcardiotomy cardiogenic shock after isolated coronary surgery
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Rustenbach, Christian Jorg, Djordjevic, Ilija, David, Lara, Ivanov, Borko, Gerfer, Stephen, Gaisendrees, Christopher, Wendt, Stefanie, Merkle, Julia, Seo, Joon, Sabashnikov, Anton, Rahmanian, Parwis, Kuhn, Elmar, Kroener, Axel, Bennink, Gerardus, Eghbalzadeh, Kaveh, Wahlers, Thorsten, Rustenbach, Christian Jorg, Djordjevic, Ilija, David, Lara, Ivanov, Borko, Gerfer, Stephen, Gaisendrees, Christopher, Wendt, Stefanie, Merkle, Julia, Seo, Joon, Sabashnikov, Anton, Rahmanian, Parwis, Kuhn, Elmar, Kroener, Axel, Bennink, Gerardus, Eghbalzadeh, Kaveh, and Wahlers, Thorsten
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Objectives Extracorporeal membrane oxygenation or extracorporeal life support (ECLS) in patients after cardiac surgery and postcardiotomy cardiogenic shock (PCS) is known to be associated with high mortality. Especially in patients after coronary artery bypass grafting (CABG) and PCS, ECLS is frequently established. The aim of this analysis was to evaluate factors associated with in-hospital mortality in patients treated with ECLS due to PCS after CABG. Methods Between August 2006 and January 2017, 92 consecutive patients with V-A ECLS due to PCS after isolated CABG were identified and included in this retrospective analysis. Patients were divided into survivors (S) and non-survivors (NS) and analyzed with risk factors of in-hospital mortality. Results In-hospital mortality added up to 61 patients (66%). Non-survivors were significantly older (60 +/- 812 (S) vs. 67 +/- 10 (NS); p = 0.013). Bilateral internal mammary artery graft was significantly more frequently used in S (23% (S) vs. 2% (NS); p = 0.001). After 24 h of ECLS support, median lactate levels were significantly higher in NS (1.9 (1.3; 3.5) mmol/L (S) vs. 3.5 (2.1; 6.3) mmol/L (NS); p = 0.001). NS suffered more often acute kidney injury requiring dialysis (42% (S) vs. 74% (NS); p = 0.002). Conclusion Mortality in patients with refractory PCS after CABG and consecutive ECLS support remains high. Failing end-organ recovery under ECLS despite optimized concomitant medical therapy is an indicator of adverse outcomes in this specific patient cohort. Moreover, total-arterial revascularization might be beneficial for cardiac recovery in patients suffering PCS after CABG and following ECLS.
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- 2022
18. Risk factors associated with in‐hospital mortality for patients with ECLS due to post cardiotomy cardiogenic shock after isolated coronary surgery
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Jörg Rustenbach, Christian, primary, Djordjevic, Ilija, additional, David, Lara, additional, Ivanov, Borko, additional, Gerfer, Stephen, additional, Gaisendrees, Christopher, additional, Wendt, Stefanie, additional, Merkle, Julia, additional, Seo, Joon, additional, Sabashnikov, Anton, additional, Rahmanian, Parwis, additional, Kuhn, Elmar, additional, Kroener, Axel, additional, Bennink, Gerardus, additional, Eghbalzadeh, Kaveh, additional, and Wahlers, Thorsten, additional
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- 2022
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19. Indications for and outcomes of interstage catheter interventions following the Norwood procedure: A single-institution study.
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Bouyaala, Yousra, Bindermann, Robert, Wendt, Stefanie, Kroener, Axel, Bennink, Gerardus, and Sreeram, Narayanswami
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CARDIAC catheterization ,CARDIAC surgery ,ECHOCARDIOGRAPHY ,AORTIC diseases ,DISEASE incidence ,RETROSPECTIVE studies ,ACQUISITION of data ,SURGERY ,PATIENTS ,TREATMENT effectiveness ,MEDICAL records ,CARDIOPULMONARY bypass - Abstract
Aims : The aim of this study was to document the incidence, types, and outcome of interstage catheter interventions following the Norwood surgical palliation. Patients and Methods : A retrospective single-center study of all patients surviving the Norwood operation was performed. All data concerning interstage catheter interventions up to the completion of the superior cavopulmonary shunt were collected. Results : Catheter interventions were performed in 62 of 94 patients (66%; 38 males). These included interventions on the aortic arch (n = 44), the branch pulmonary arteries (PAs) (n = 17), and the Sano shunt (n = 14). Multiple interventions and repeat interventions were common. The minimum aortic arch diameter (pre- versus posttreatment) increased from median 3.1 (2.3-3.3) mm to 5.1 (4.2-6.2) mm (P < 0.001). The catheter pullback gradient decreased from 40 (36-46) mmHg to 9 (5-10) mmHg (P < 0.001), and the echocardiographic gradient from 54 (45-64) mmHg to 12 (10-16) mmHg (P < 0.001). The branch PA diameters increased from 2.4 (2.1-3.0) mmHg to 4.7 (4.2-5.1) mmHg (P < 0.001). The minimum Sano shunt diameters increased from 2.0 (1.5-2.1) mm to 5.9 (5.8--6.0) mm (P < 0.001); this was associated with an improvement in systemic saturation from 63% (60%-65%) to 80% (79-82%) (P < 0.001). Unexpected interstage death at home occurred in two patients who had received no interventions. The remainder received a superior cavopulmonary shunt palliation. Conclusions : Catheter interventions were common. Systematic follow-up and a low threshold for reintervention are essential to the success of staged surgical palliation for this patient cohort. [ABSTRACT FROM AUTHOR]
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- 2023
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20. Reports about error estimators and data-driven adaptations for modelling and optimization errors
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Bärmann, Andreas, Martin, Alexander, Staszek, Jonasz, Ramlau, Ronny, Stadler, Bernadett, Gutiérrez Pérez, José Carlos, Dittmer, Sören, Kluth, Tobias, Maaß, Peter, Otero Baguer, Daniel, Kroener, Axel, Hintermüller, Michael, Benamou, Jean-David, Rukhaia, Giorgi, and IJzerman, Wilbert
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Optimization, Error estimators, Algorithms - Abstract
In the ROMSOC project, we develop specially-tailored algorithmic approaches to solve the practical problems of our industry partners. The mathematical fields involved in solving these problems are as diverse as the problems themselves. Thus, our project covers a very broad range within applied mathematics: from discrete optimization to inverse problems, from deep learning to optimal control. What all these fields have in common is that error estimation is an important topic in order to quantify the quality of a computed solution. Naturally, all of them their own error measures and different ways of computing and using them. This report summarizes the state of the art methods in the respective fields concerning error measures and their usefulness in solving real-world problems.
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- 2020
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21. Management of out-of hospital cardiac arrest patients with extracorporeal cardiopulmonary resuscitation in 2021
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Gaisendrees, Christopher, Vollmer, Matias, Walter, Sebastian G., Djordjevic, Ilija, Eghbalzadeh, Kaveh, Kaya, Suereyya, Elderia, Ahmed, Ivanov, Borko, Gerfer, Stephen, Kuhn, Elmar, Sabashnikov, Anton, Kahlert, Heike A., Deppe, Antje C., Kroener, Axel, Mader, Navid, Wahlers, Thorsten, Gaisendrees, Christopher, Vollmer, Matias, Walter, Sebastian G., Djordjevic, Ilija, Eghbalzadeh, Kaveh, Kaya, Suereyya, Elderia, Ahmed, Ivanov, Borko, Gerfer, Stephen, Kuhn, Elmar, Sabashnikov, Anton, Kahlert, Heike A., Deppe, Antje C., Kroener, Axel, Mader, Navid, and Wahlers, Thorsten
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Introduction Over the last decade, eCPR programs have become more and more popular, at least amongst high-volume centers. Despite its rise in popularity and promising outcome, strategies concerning pre- and post-implantation of VA-ECMO remain at least debatable. Besides, integrating the appropriate set-up, managing anticoagulation, implementing LV-venting, and predicting neurological outcome play important roles in caring for thise highly selective patient-collective. We sought to present our institutional ' s techniques for establishing an eCPR program and managing patients peri- and post implantation in eCPR-runs. Areas covered This manuscript covers the majority of clinical concerns and parameters for establishing an eCPR program and its recent advantages. We will describe a safe way of cannulation, setting anticoagulation goals, strategies for LV-venting and ICU-treatment. Also included, an elaboration on neurological and cardiac prognostication Expert Opinion We advocate ultrasound-guided cannula placement in eCPR patients. Also, we emphasize the importance of using stiffer wires and smaller arterial cannula sizes due to the different physiological parameters of OHCA patients. After cannulation, we aim for lower flow goals, the concept of 'partial VA-ECMO,' and lower anticoagulatory targets. LV-venting with Impella should remain an individual case to case decision.
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- 2021
22. Effect of Thawing on Nitric Oxide Synthase III and Apoptotic Markers in Cryopreserved Human Allografts
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Geissler, Hans J., Fischer, Uwe M., Foerster, Saskia, Krahwinkel, Andreas, Antonyan, Albert, Kroener, Axel, Addicks, Klaus, Mehlhorn, Uwe, and Bloch, Wilhelm
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- 2006
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23. Single-center experience with the frozen elephant trunk procedure in 111 patients with complex aortic disease
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Liakopoulos, Oliver J., primary, Kroener, Axel, additional, Sabashnikov, Anton, additional, Zeriouh, Mohamed, additional, Ahmad, Wael, additional, Choi, Yeong-Hoon, additional, and Wahlers, Thorsten, additional
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- 2020
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24. Percutaneous mitral annuloplasty device leaves free access to cardiac veins for resynchronization therapy
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Hoppe, Uta C., Brandt, Mathias C., Degen, Hubertus, Dodos, Fotini, Schneider, Thorsten, Stoepel, Carsten, Kroener, Axel, and Haude, Michael
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- 2009
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25. Daily Assessment of Organ Dysfunction and Survival in Intensive Care Unit Cardiac Surgical Patients
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Hekmat, Khosro, Kroener, Axel, Stuetzer, Hartmut, Schwinger, Robert H.G., Kampe, Sandra, Bennink, Gerardus B.W.E., and Mehlhorn, Uwe
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- 2005
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26. Early and long-term outcomes comparing neonates, infants, and preadolescents requiring extracorporeal membrane oxygenation for heart failure
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Sabashnikov, Anton, Merkle, Julia, Azizov, Farid, Djordjevic, Ilija, Eghbalzadeh, Kaveh, Tunggal, Irawati, Weber, Carolyn, Weixler, Viktoria, Rustenbach, Christian, Zeriouh, Mohamed, Kroener, Axel, Wahlers, Thorsten, Bennink, Gerardus, Sabashnikov, Anton, Merkle, Julia, Azizov, Farid, Djordjevic, Ilija, Eghbalzadeh, Kaveh, Tunggal, Irawati, Weber, Carolyn, Weixler, Viktoria, Rustenbach, Christian, Zeriouh, Mohamed, Kroener, Axel, Wahlers, Thorsten, and Bennink, Gerardus
- Abstract
Background: Application of extracorporeal membrane oxygenation in pediatric patients with severe heart failure steadily increases. Differentiation of outcomes and survival of diverse pediatric groups is of interest for adequate therapy. Methods: Between January 2008 and December 2016, a total of 39 pediatric patients needed veno-arterial extracorporeal membrane oxygenation support in our department. Patients were retrospectively divided into three groups: neonates (<30 days), infants (>30 days/<1 year), and toddlers/preadolescents (>1 year). Early outcomes as well as mid- and long-term survival up to 7-year follow-up were analyzed. Results: Basic demographics significantly differed in terms of age, height, and weight among the groups in accordance with the intended group categorization (p < 0.05). Survival after 30 days of extracorporeal membrane oxygenation application was equally distributed among the groups, and 44% of all patients survived. In terms of survival to discharge, no significant differences were found among groups. In total, 28% of patients survived up to 7 years. Infants were significantly more likely to undergo elective surgery (p < 0.001) and were predominantly weaned off extracorporeal membrane oxygenation, whereas need for urgent surgery (p < 0.001) was significantly higher in neonate group in comparison to other groups. Multinominal logistic regression analysis revealed significantly higher odds for need for re-exposure in infant group in comparison to toddler/preadolescent group as well as for incidence of neurological impairment of toddler/preadolescent group in comparison to neonate group (odds ratio = 14.67, p = 0.009 and odds ratio = 34.67, p = 0.004, respectively). Kaplan-Meier survival estimation analysis revealed no significant differences in terms of mid- and long-term survival among the groups (Breslow p = 0.198 and log-rank p = 0.213, respectively). Conclusion: Veno-arterial extracorporeal membrane oxygenation is a lifesaving therapeu
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- 2020
27. Single-center experience with the frozen elephant trunk procedure in 111 patients with complex aortic disease
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Liakopoulos, Oliver J., Kroener, Axel, Sabashnikov, Anton, Zeriouh, Mohamed, Ahmad, Wael, Choi, Yeong-Hoon, Wahlers, Thorsten, Liakopoulos, Oliver J., Kroener, Axel, Sabashnikov, Anton, Zeriouh, Mohamed, Ahmad, Wael, Choi, Yeong-Hoon, and Wahlers, Thorsten
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Background: The frozen elephant trunk (FET) technique is increasingly used for the treatment of acute and chronic aortic arch disease. This study reports our single center experience with the FET technique in patients with complex aortic disease. Methods: Between 2009 and 2019, 111 consecutive patients underwent aortic arch surgery in our institution using the FET technique for acute type A dissection (AAD group; n=75) or non-acute type A dissection (non-AAD group; n=36; 10 patients with chronic type A dissection; 26 patients with aneurysm), respectively. Relevant perioperative data, including 30-day mortality and neurological complications, were retrospectively obtained from our electronic patients records, including follow-up (FU) data of outpatient clinical visits and computed tomography (CT). Results: Thirty-day mortality in the entire FET cohort was 16.2% (AAD 18.7% vs. non-AAD 11.1%; n=0.414). Severe brain injury was the leading cause of death in AAD patients (12.0% vs. 0% non-AAD; P=0.030). Overall permanent stroke and spinal cord injury was 12.6% and 3.6%. Four patients in the AAD group developed paraplegia and permanent stroke rate was significantly higher in AAD compared to non-AAD patients (17.3% vs. 2.8%; P=0.034). One, 3- and 5-year survival rates were 78.7%+/- 4.0%, 72.2%+/- 4.8%, and 64.3%+/- 6.8% for the total cohort; survival at 1-, 3- and 5-year was 76.7%+/- 5.0%, 71.0%+/- 6.1%, and 64.5%+/- 8.3% for the AAD cohort compared to 83.1%+/- 6.3%, 75.0%+/- 7.9% and 66.7% for non-AAD patients (P=0.579), respectively. Conclusions: Our single-center experience confirms good early and mid-term survival after the FET procedure in patients presenting with AAD, CAD and aneurysm. Future efforts should focus on reduction of severe neurological complication.
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- 2020
28. Outcomes and factors associated with early mortality in pediatric and neonatal patients requiring extracorporeal membrane oxygenation for heart and lung failure
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Azizov, Farid, primary, Merkle, Julia, additional, Fatullayev, Javid, additional, Eghbalzadeh, Kaveh, additional, Djordjevic, Ilija, additional, Weber, Carolyn, additional, Saenko, Sergey, additional, Kroener, Axel, additional, Zeriouh, Mohamed, additional, Sabashnikov, Anton, additional, Bennink, Gerardus, additional, and Wahlers, Thorsten, additional
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- 2019
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29. Outcomes and factors associated with early mortality in pediatric and neonatal patients requiring extracorporeal membrane oxygenation for heart and lung failure
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Azizov, Farid, Merkle, Julia, Fatullayev, Javid, Eghbalzadeh, Kaveh, Djordjevic, Ilija, Weber, Carolyn, Saenko, Sergey, Kroener, Axel, Zeriouh, Mohamed, Sabashnikov, Anton, Bennink, Gerardus, Wahlers, Thorsten, Azizov, Farid, Merkle, Julia, Fatullayev, Javid, Eghbalzadeh, Kaveh, Djordjevic, Ilija, Weber, Carolyn, Saenko, Sergey, Kroener, Axel, Zeriouh, Mohamed, Sabashnikov, Anton, Bennink, Gerardus, and Wahlers, Thorsten
- Abstract
Background: Mortality and morbidity after surgical repair for complex congenital heart defects and severe cardiopulmonary failure on extracorporeal membrane oxygenation (ECMO) support remain high despite significant advances in medical management and technological improvements. We report on outcomes and factors after using ECMO in our surgical pediatric population including short- and long-term survival. Methods: A total of 45 neonatal and pediatric patients were identified who needed ECMO in our department between January 2008 and December 2016. In 41 cases (91%) a vaECMO (ECLS) was implemented, whereas 4 patients (9%) received vvECMO treatment for respiratory failure. In 33 cases vaECMO was implanted following cardiac surgery for congenital heart disease (CHD), whereas in 8 patients ECMO was utilized by means of extracorporeal cardiopulmonary resuscitation (eCPR) following refractory cardiac arrest. The primary endpoint of the present study was survival to discharge and long-term survival free from neurological impairments. Univariate and bivariate analysis was performed to address predictors for outcome. Kaplan-Meier survival analysis was used to address mid- and long-term survival. Results: Median [IQR] duration of ECMO support was 3 [2, 5] days (range, 1-17 days). Median age at ECMO implantation was 128 [14, 1,813] days, median weight of patients was 5.4 [3.3, 12] kg. Totally 10 patients included in this study were diagnosed with concomitant genetic conditions. A total of 20 (44%) patients were successfully weaned off ECMO (survived >24 h after ECMO explantation), whereas 15 (33%) of them survived to discharge. Single ventricle (SV) repair was performed in 14, biventricular repair in 19 patients. Neonates (<30 days of age), female patients, patients with genetic conditions, SV repair patients, and eCPR patient cohort showed lower odds of survival on ECMO. Failed myocardial recovery (P=0.001), profound circulatory failure despite a high dose of catecholamines (P
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- 2019
30. Pediatric patients requiring extracorporeal membrane oxygenation in heart failure: 30-day outcomes; mid- and long-term survival. A single center experience
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Merkle, Julia, Azizov, Farid, Sabashnikov, Anton, Weixler, Viktoria, Weber, Carolyn, Djordjevic, Ilija, Eghbalzadeh, Kaveh, Kroener, Axel, Zeriouh, Mohamed, Wahlers, Thorsten, Bennink, Gerardus, Merkle, Julia, Azizov, Farid, Sabashnikov, Anton, Weixler, Viktoria, Weber, Carolyn, Djordjevic, Ilija, Eghbalzadeh, Kaveh, Kroener, Axel, Zeriouh, Mohamed, Wahlers, Thorsten, and Bennink, Gerardus
- Abstract
Nowadays, an increasing number of neonatal and pediatric patients with severe heart failure benefits from extracorporeal membrane oxygenation (ECMO) support. A total of 39 pediatric patients needed venoarterial ECMO (vaECMO) support in our department between January 2008 and December 2016. Patients were retrospectively divided in two groups: 30-day survivor group (17 patients) and 30-day nonsurvivor group (22 patients). Outcome and factors predictive for 30-day mortality and mid- as well as long-term survival up to 7-year follow-up were analyzed by univariate analysis and Kaplan-Meier survival estimation. Basic demographics and preoperative characteristics did not differ between groups (P > 0.05). 67% of patients were successfully weaned off ECMO and 44% survived 30-day after ECMO application. After 7-year follow-up 28% of pediatric patients were alive. Thirty-day survivors were significantly more likely to undergo elective cardiac surgery (P = 0.001), whereas significantly more 30-day nonsurvivors underwent urgent surgery (P = 0.004). Odds of incidence of catecholamine refractory circulatory failure, failed myocardial recovery, and cerebral edema was significantly higher in 30-day nonsurvivor group (41.6-fold, 16-fold, and 2.5-fold, respectively). Kaplan-Meier survival estimation analysis revealed significant differences in terms of mid- and long-term survival among neonates, infants, toddlers, and preadolescents (Breslow P = 0.037 and Log-Rank P = 0.028, respectively). vaECMO provides an efficient therapy option for life-threatening heart disorders in neonates and pediatric patients being at high risk for myocardial failure leading to circulatory arrest. Urgency of surgery effected on higher mortality, but there was no difference in terms of mortality in 30-day survivor group in comparison to 30-day nonsurvivor group among neonates, infants, toddlers, and preadolescents.
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- 2019
31. Impact of hypertension on early outcomes and long-term survival of patients undergoing aortic repair with Stanford A dissection
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Merkle, Julia, primary, Sabashnikov, Anton, additional, Deppe, Antje-Christin, additional, Zeriouh, Mohamed, additional, Eghbalzadeh, Kaveh, additional, Weber, Carolyn, additional, Rahmanian, Parwis, additional, Kuhn, Elmar, additional, Madershahian, Navid, additional, Kroener, Axel, additional, Choi, Yeong-Hoon, additional, Kuhn-Régnier, Ferdinand, additional, Liakopoulos, Oliver, additional, and Wahlers, Thorsten, additional
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- 2018
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32. Angiosarcoma of the Left Atrium: A Case Report
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Schlachtenberger, Georg, Gerfer, Stephen, Kroener, Axel, Wahlers, Thorsten, Schlachtenberger, Georg, Gerfer, Stephen, Kroener, Axel, and Wahlers, Thorsten
- Abstract
Background Primary cardiac tumors are rare, andmany diagnosed tumors are benign with an incidence of 0.001% to 0.03%. The primary angiosarcoma is one of the malignant entities. Discussion We discuss a case report of a 76-year-old male who underwent a preoperative diagnosis for an upcoming shoulder operation when his cardiologist diagnosed a large cardiac tumor. The patient was referred to our department where he received further diagnostics. The transesophageal echocardiography and the cardiac-magnetic resonance imaging showed a massive tumor with a dimension of 8.6 x 5.6 cm with no signs of malignity. Method The operation was performed by standard median sternotomy. The tumor was adherent to the septum and the left atrium, and we were able to remove the specimen in toto. Pathological examinations showed an angiosarcoma with neovascularization and core expression of ERG+ and cytoplasmic expression of CD31+/CD34+, due to the size of the mass. The resection of primary cardiac tumors is mostly the therapy of choice, but in this case concerning an angiosarcoma the prognosis is poor, considering that the angiosarcoma responds very badly to chemotherapy and radiotherapy.
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- 2018
33. Impact of hypertension on early outcomes and long-term survival of patients undergoing aortic repair with Stanford A dissection
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Merkle, Julia, Sabashnikov, Anton, Deppe, Antje-Christin, Zeriouh, Mohamed, Eghbalzadeh, Kaveh, Weber, Carolyn, Rahmanian, Parwis, Kuhn, Elmar, Madershahian, Navid, Kroener, Axel, Choi, Yeong-Hoon, Kuhn-Regnier, Ferdinand, Liakopoulos, Oliver, Wahlers, Thorsten, Merkle, Julia, Sabashnikov, Anton, Deppe, Antje-Christin, Zeriouh, Mohamed, Eghbalzadeh, Kaveh, Weber, Carolyn, Rahmanian, Parwis, Kuhn, Elmar, Madershahian, Navid, Kroener, Axel, Choi, Yeong-Hoon, Kuhn-Regnier, Ferdinand, Liakopoulos, Oliver, and Wahlers, Thorsten
- Abstract
Introduction: Stanford A acute aortic dissection (AAD) is a life-threatening emergency, typically occurring in hypertensive patients, requiring immediate surgical repair. The aim of this study was to evaluate early outcomes and long-term survival of hypertensive patients in comparison to normotensive patients suffering from Stanford A AAD. Methods: In our center, 240 patients with Stanford A AAD underwent aortic surgical repair from January 2006 to April 2015. After statistical and logistic regression analysis, Kaplan-Meier survival estimation was performed, with up to 9-year follow-up. Results: The proportion of hypertensive patients suffering from Stanford A AAD was 75.4% (n=181). There were only few statistically significant differences in terms of basic demographics, comorbidities, preoperative baseline and clinical characteristics of hypertensive patients in comparison to normotensive patients. Hypertensive patients were significantly older (p=0.008), more frequently received hemi-arch repair (p=0.028) and selective brain perfusion (p=0.001). Our study showed similar statistical results in terms of 30-day mortality (p=0.196), long-term overall cumulative survival of patients (Log-Rank p=0.506) and survival of patients free from cerebrovascular events (Log-Rank p=0.186). Furthermore, subgroup analysis for long-term survival in terms of men (Log-Rank p=0.853), women (Log-Rank p=0.227), patients under and above 65 years of age (Log-Rank p=0.188 and Log-Rank p=0.602, respectively) and patients undergoing one of the three types of aortic repair surgery showed similar results for normotensive and hypertensive patient groups. Subgroup analysis for long-term survival of patients free from cerebrovascular events for women, patients under 65 years of age and patients undergoing aortic arch repair showed significant differences between the two groups in favor of hypertensive patients. Conclusions: Hypertensive patients suffering from Stanford A AAD were older, more freque
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- 2018
34. Impact of gender on long-term outcomes after surgical repair for acute Stanford A aortic dissection: a propensity score matched analysis
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Sabashnikov, Anton, Heinen, Stephanie, Deppe, Antje Christin, Zeriouh, Mohamed, Weymann, Alexander, Slottosch, Ingo, Eghbalzadeh, Kaveh, Popov, Aron-Frederik, Liakopoulos, Oliver, Rahmanian, Parwis B., Madershahian, Navid, Kroener, Axel, Choi, Yeong-Hoon, Kuhn-Regnier, Ferdinand, Simon, Andre R., Wahlers, Thorsten, Wippermann, Jens, Sabashnikov, Anton, Heinen, Stephanie, Deppe, Antje Christin, Zeriouh, Mohamed, Weymann, Alexander, Slottosch, Ingo, Eghbalzadeh, Kaveh, Popov, Aron-Frederik, Liakopoulos, Oliver, Rahmanian, Parwis B., Madershahian, Navid, Kroener, Axel, Choi, Yeong-Hoon, Kuhn-Regnier, Ferdinand, Simon, Andre R., Wahlers, Thorsten, and Wippermann, Jens
- Abstract
OBJECTIVES: Previous research suggests that female gender is associated with increased mortality rates after surgery for Stanford A acute aortic dissection (AAD). However, women with AAD usually present with different clinical symptoms that may bias outcomes. Moreover, there is a lack of long-term results regarding overall mortality and freedom from major cerebrovascular events. We analysed the impact of gender on long-term outcomes after surgery for Stanford A AAD by comparing genders with similar risk profiles using propensity score matching. METHODS: A total of 240 patients operated for Stanford A AAD were included in this study. To control for selection bias and other con-founders, propensity score matching was applied to gender groups. RESULTS: After propensity score matching, the gender groups were well balanced in terms of risk profiles. There were no statistically significant differences regarding duration of cardiopulmonary bypass (P = 0.165) and duration of aortic cross-clamp time (P = 0.111). Female patients received less fresh frozen plasma (P = 0.021), had shorter stays in the intensive care unit (P = 0.031), lower incidence of temporary neurological dysfunction (P < 0.001) and lower incidence of dialysis (P = 0.008). There were no significant differences regarding intraoperative mortality (P = 1.000), 30-day mortality (P = 0.271), long-term overall cumulative survival (P = 0.954) and long-term freedom from cerebrovascular events (P = 0.235) with up to a 9-year follow-up. CONCLUSIONS: Considering patients with similar risk profiles, female gender per se is not associated with worse long-term survival and freedom from stroke after surgical aortic repair. Moreover, female patients might even benefit from a smoother early postoperative course and lower incidence of early postoperative complications.
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- 2017
35. Six-years survival and predictors of mortality after CABG using cold vs. warm blood cardioplegia in elective and emergent settings
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Zeriouh, Mohamed, Heider, Ammar, Rahmanian, Parwis B., Choi, Yeong-Hoon, Sabashnikov, Anton, Scherner, Maximillian, Popov, Aron-Frederik, Weymann, Alexander, Ghodsizad, Ali, Deppe, Antje-Christin, Kroener, Axel, Kuhn-Regnier, Ferdinand, Wippermann, Jens, Wahlers, Thorsten, Zeriouh, Mohamed, Heider, Ammar, Rahmanian, Parwis B., Choi, Yeong-Hoon, Sabashnikov, Anton, Scherner, Maximillian, Popov, Aron-Frederik, Weymann, Alexander, Ghodsizad, Ali, Deppe, Antje-Christin, Kroener, Axel, Kuhn-Regnier, Ferdinand, Wippermann, Jens, and Wahlers, Thorsten
- Abstract
Background: The aim of this study was to determine whether intermittent warm blood cardioplegia (IWC) is associated with comparable myocardial protection compared to cold blood cardioplegia (ICC) in patients undergoing elective vs. emergent CABG procedures. Methods: Out of 2292 consecutive patients who underwent isolated on-pump CABG surgery using cardioplegic arrest either with ICC or IWC between January 2008 and December 2010, 247 consecutive emergent patients were identified and consecutively matched 1: 2 with elective patients based on gender, age (<50 years, 50-70 years, >70 years) and ejection fraction (<40 %, 40-50 %, >50 %). Perioperative outcomes and long-term mortality were compared between ICC and IWC strategies and predictors for 30-day mortality and perioperative myocardial injury were identified in both elective and emergent subgroups of patients. Results: Preoperative demographics and baseline characteristics, logistic Euroscore, CPB-time, number of distal anastomoses and LIMA-use were comparable. Aortic cross clamp time was significantly longer in the IWC-group regardless of the urgency of the procedure (p = 0.05 and p = 0.015 for emergent and elective settings). There were no significant differences regarding ICU-stay, ventilation time, total blood loss and need for dialysis. The overall 30-day, 1-, 3- and 6-year survival of the entire patient cohort was 93.7, 91.8, 90.4 and 89.1 %, respectively, with significantly better outcomes when operated electively (p < 0.001) but no differences between ICC and IWC both in elective (p = 0.857) and emergent (p = 0.741) subgroups. Multivariate analysis did not identify the type of cardioplegia as a predictor for 30-day mortality and for perioperative myocardial injury. However, independent factors predictive of 30-day mortality were: EF < 40 % (OR 3.66; 95 % CI: 1.79-7.52; p < 0.001), atrial fibrillation (OR 3.33; 95 % CI: 1.49-7.47; p < 0.003), peripheral artery disease (OR 2.51; 95 % CI: 1.13-5.55; p < 0.023)
- Published
- 2015
36. Evaluation of risk factors for transient neurological dysfunction and adverse outcome after repair of acute type A aortic dissection in 122 consecutive patients
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Haldenwang, Peter L., Wahlers, Thorsten, Himmels, Anja, Wippermann, Jens, Zeriouh, Mohamed, Kroener, Axel, Kuhr, Kathrin, Strauch, Justus T., Haldenwang, Peter L., Wahlers, Thorsten, Himmels, Anja, Wippermann, Jens, Zeriouh, Mohamed, Kroener, Axel, Kuhr, Kathrin, and Strauch, Justus T.
- Abstract
The aim of this retrospective study was to assess pre- and intraoperative factors leading to neurological complications and early death following repair of acute type A aortic dissection (ATAAD). There were 122 patients (85 male, age: 58.6 +/- 12.5 years) with ATAAD, treated consecutively from August 2003 to August 2010. Pre- and intraoperative variables were analysed using a logistic regression model in order to identify risk factors for temporary neurological dysfunction (TND) and adverse outcome (AO), defined as stroke and 30-day mortality. The 30-day mortality rate was 16.4%. Forty-one patients (33.6%) suffered transient neurological dysfunction and 20 (16.4%) had a postoperative stroke. Mean hypothermic circulatory arrest (HCA) temperature was 24 +/- 4 degrees C. Selective cerebral perfusion (SCP) was performed in 99 (82%) patients, with a mean SCP flow rate of 10.3 ml/kg/min. The duration of lower body ischaemia (LBI) was 36 +/- 27 min, of HCA 8.7 +/- 15.5 min and of SCP 34 +/- 28 min, respectively. Male gender [odds ratio (OR): 3.30, 95% confidence interval (CI): 1.15-9.47], diabetes (OR: 3.95, 95% CI: 1.18-13.24), compromised consciousness (OR: 6.65, 95% CI: 1.41-31.48) and manifest arterial atherosclerosis (OR: 6.68, 95% CI: 1.31-34.09) were detected as risk factors for TND, whereas a high body mass index (OR: 1.14, 95% CI: 1.01-1.3), a preoperative malperfusion syndrome (OR: 2.28, 95% CI: 0.84-6.18) and left ventricular ejection fraction < 50% (OR: 3.84, 95% CI: 1.41-10.43) were detected as independent predictors for an AO. A dissection entry localized in the aortic arch or the descending aorta independently increased the risk for a postoperative stroke. A prolonged LBI increased the risk for AO (OR: 1.02, 95% CI: 1.00-1.04), whereas femoral cannulation showed a trend to an increased stroke incidence (OR: 4.2, 95% CI: 0.8-21.3). Regardless of standardized neuroprotective techniques, treatment of ATAAD remains a high-risk operation. Preoperatively, the pres
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- 2012
37. Preoperative risk stratification models fail to predict hospital cost of cardiac surgery patients
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Badreldin, Akmal MA, primary, Doerr, Fabian, additional, Kroener, Axel, additional, Wahlers, Thorsten, additional, and Hekmat, Khosro, additional
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- 2013
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38. Prediction of mortality in intensive care unit cardiac surgical patients☆☆☆
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Hekmat, Khosro, primary, Doerr, Fabian, additional, Kroener, Axel, additional, Heldwein, Matthias, additional, Bossert, Torsten, additional, Badreldin, Akmal M.A., additional, and Lichtenberg, Artur, additional
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- 2010
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39. Effect of clopidogrel on perioperative blood loss and transfusion in coronary artery bypass graft surgery
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Badreldin, Akmal, primary, Kroener, Axel, additional, Kamiya, Hiroyuki, additional, Lichtenberg, Artur, additional, and Hekmat, Khosro, additional
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- 2010
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40. Reports about error estimators and data-driven adaptations for modelling and optimization errors
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Bärmann, Andreas, Martin, Alexander, Staszek, Jonasz, Ramlau, Ronny, Stadler, Bernadett, Gutiérrez Pérez, José Carlos, Dittmer, Sören, Kluth, Tobias, Maaß, Peter, Otero Baguer, Daniel, Kroener, Axel, and Hintermüller, Michael
- Subjects
Optimization, Error estimators, Algorithms ,3. Good health - Abstract
In the ROMSOC project, we develop specially-tailored algorithmic approaches to solve the practical problems of our industry partners. The mathematical fields involved in solving these problems are as diverse as the problems themselves. Thus, our project covers a very broad range within applied mathematics: from discrete optimization to inverse problems, from deep learning to optimal control. What all these fields have in common is that error estimation is an important topic in order to quantify the quality of a computed solution. Naturally, all of them their own error measures and different ways of computing and using them. This report summarizes the state of the art methods in the respective fields concerning error measures and their usefulness in solving real-world problems.
41. Reports about error estimators and data-driven adaptations for modelling and optimization errors
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Bärmann, Andreas, Martin, Alexander, Staszek, Jonasz, Ramlau, Ronny, Stadler, Bernadett, Gutiérrez Pérez, José Carlos, Dittmer, Sören, Kluth, Tobias, Maaß, Peter, Otero Baguer, Daniel, Kroener, Axel, and Hintermüller, Michael
- Subjects
Optimization, Error estimators, Algorithms ,3. Good health - Abstract
In the ROMSOC project, we develop specially-tailored algorithmic approaches to solve the practical problems of our industry partners. The mathematical fields involved in solving these problems are as diverse as the problems themselves. Thus, our project covers a very broad range within applied mathematics: from discrete optimization to inverse problems, from deep learning to optimal control. What all these fields have in common is that error estimation is an important topic in order to quantify the quality of a computed solution. Naturally, all of them their own error measures and different ways of computing and using them. This report summarizes the state of the art methods in the respective fields concerning error measures and their usefulness in solving real-world problems., Project deliverable D4.1
42. Heart surgery and simultaneous carotid endarterectomy-10-years single-center experience
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Gerfer, Stephen, Ivanov, Borko, Krasivskyi, Ihor, Djordjevic, Ilija, Gaisendrees, Christopher, Avgeridou, Soi, Kuhn-Regnier, Ferdinand, Mader, Navid, Rahmanian, Parwis, Kroener, Axel, Kuhn, Elmar, Wahlers, Thorsten, Gerfer, Stephen, Ivanov, Borko, Krasivskyi, Ihor, Djordjevic, Ilija, Gaisendrees, Christopher, Avgeridou, Soi, Kuhn-Regnier, Ferdinand, Mader, Navid, Rahmanian, Parwis, Kroener, Axel, Kuhn, Elmar, and Wahlers, Thorsten
- Abstract
Background Patients with coronary artery heart disease frequently suffer concomitant carotid vascular disease and are at high perioperative risk for neurological adverse events. Several concepts regarding the timing and modality of carotid revascularization are controversially discussed in patients with heart disease. Current guidelines recommendations on myocardial revascularization recommend a concomitant carotid endarterectomy (CEA) in patients with a history of stroke/transient ischemic attack (TIA) or 50-99% grade of the carotid stenosis. Our study aimed to analyze early outcome parameters of patients undergoing coronary artery bypass grafting (CABG), but also including concomitant heart valve surgery and simultaneous CEA. Methods This study retrospectively analyzed a cohort of 111 patients from our institutional database undergoing heart surgery with CABG or heart-valve surgery between 2010 and 2020 with concomitant carotid surgery due to significant carotid stenosis. Results Patients undergoing heart and simultaneous carotid surgery were 77 +/- 8.0 years of age with a body mass index of 28 +/- 1.7 kg/m(2) and a mean EuroSCORE II of 6.5 +/- 2.3. Most patients (61%) had a smoking history and arterial hypertension (97%). The preoperative mean grade of internal carotid stenosis was 87 +/- 4.2%, 13% of patients suffered from internal carotid artery stenosis on both sites. In total, 4.5% of patients had previously undergone internal carotid artery intervention before and 6.3% had a history of stroke with a persistent neurologic disorder in 1.8%, 8.9% of cases had prior TIA. Thirty-day all-cause mortality was 6.3% and postoperative neurologic events occurred with 7.2% TIA and 4.5% of disabling stroke. Conclusion Within the reported patient population of coronary artery heart disease and significant internal carotid stenosis, a one-time approach with CABG or heart-valve surgery and CEA is safe and feasible as justified by clinical and neurological postoperative outco
43. Impact of gender on long-term outcomes after surgical repair for acute Stanford A aortic dissection: a propensity score matched analysis.
- Author
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Sabashnikov A, Heinen S, Deppe AC, Zeriouh M, Weymann A, Slottosch I, Eghbalzadeh K, Popov AF, Liakopoulos O, Rahmanian PB, Madershahian N, Kroener A, Choi YH, Kuhn-Régnier F, Simon AR, Wahlers T, and Wippermann J
- Subjects
- Aged, Female, Follow-Up Studies, Germany epidemiology, Humans, Incidence, Male, Middle Aged, Retrospective Studies, Risk Factors, Sex Distribution, Sex Factors, Survival Rate trends, Time Factors, Aortic Dissection surgery, Aortic Aneurysm, Thoracic surgery, Postoperative Complications epidemiology, Propensity Score, Vascular Surgical Procedures methods
- Abstract
Objectives: Previous research suggests that female gender is associated with increased mortality rates after surgery for Stanford A acute aortic dissection (AAD). However, women with AAD usually present with different clinical symptoms that may bias outcomes. Moreover, there is a lack of long-term results regarding overall mortality and freedom from major cerebrovascular events. We analysed the impact of gender on long-term outcomes after surgery for Stanford A AAD by comparing genders with similar risk profiles using propensity score matching., Methods: A total of 240 patients operated for Stanford A AAD were included in this study. To control for selection bias and other confounders, propensity score matching was applied to gender groups., Results: After propensity score matching, the gender groups were well balanced in terms of risk profiles. There were no statistically significant differences regarding duration of cardiopulmonary bypass ( P = 0.165) and duration of aortic cross-clamp time ( P = 0.111). Female patients received less fresh frozen plasma ( P = 0.021), had shorter stays in the intensive care unit ( P = 0.031), lower incidence of temporary neurological dysfunction ( P < 0.001) and lower incidence of dialysis ( P = 0.008). There were no significant differences regarding intraoperative mortality ( P = 1.000), 30-day mortality ( P = 0.271), long-term overall cumulative survival ( P = 0.954) and long-term freedom from cerebrovascular events ( P = 0.235) with up to a 9-year follow-up., Conclusions: Considering patients with similar risk profiles, female gender per se is not associated with worse long-term survival and freedom from stroke after surgical aortic repair. Moreover, female patients might even benefit from a smoother early postoperative course and lower incidence of early postoperative complications., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
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