Marianne Schmid Daners


Last Name

Schmid Daners

First Name

Marianne

ORCID

0000-0002-6411-8871

Organisational unit

09563 - Zeilinger, Melanie / Zeilinger, Melanie

Search Results

Publications 1 - 10 of 158
  • The impact of right ventricular hemodynamics on the performance of a left ventricular assist device in a numerical simulation model
    Item type: Journal Article
    Thut, Titus L.Z.; Petrou, Anastasios; Meboldt, Mirko; et al. (2023)
    Biomedical Engineering / Biomedizinische Technik
    Objectives Left ventricular assist devices (LVADs) have been established as alternative to heart transplantation for patients with end-stage heart failure refractory to medical therapy. Right heart failure (RHF) after LVAD implantation is associated with inferior outcome. Its preoperative anticipation may influence the selection between a pure left ventricular and a biventricular device type and, thus, improve outcomes. Reliable algorithms to predict RHF are missing. Methods A numerical model was used for simulation of a cardiovascular circulation. The LVAD was placed as parallel circuit between left ventricle and aorta. In contrast to other studies, the dynamic hydraulic behavior of a pulsatile LVAD was replaced by that of a continuous LVAD. A variety of hemodynamic states was tested mimicking different right heart conditions. Adjustable parameters included heart rate (HR), pulmonary vascular resistance (PVR), tricuspid regurgitation (TR), right ventricular contractility (RVC) and pump speed. Outcome parameters comprised central venous pressure (CVP), mean pulmonary artery pressure (mPAP), cardiac output (CO) and occurrence of suction. Results Alteration of HR, PVR, TR, RVC and pump speed resulted in diverse effects on CO, CVP and mPAP, resulting in improvement, impairment or no change of the circulation, depending on the degree of alteration. Conclusions The numerical simulation model allows prediction of circulatory changes and LVAD behaviour following variation of hemodynamic parameters. Such a prediction may be of particular advantage to anticipate RHF after LVAD implantation. It may help preoperatively to choose the appropriate strategy of only left ventricular or both left and right ventricular support.
  • In-vitro investigation of endothelial monolayer retention on an inflow VAD cannula inside a beating heart phantom
    Item type: Journal Article
    Magkoutas, Konstantinos; Chala, Nafsika; Wu, Xi; et al. (2023)
    Biomaterials Advances
    Ventricular assist devices (VADs) provide an alternative solution to heart transplantation for patients with end-stage heart failure. Insufficient hemocompatibility of VAD components can result in severe adverse events, such as thromboembolic stroke, and readmissions. To enhance VAD hemocompatibility, and avoid thrombus formation, surface modification techniques and endothelialization strategies are employed. In this work, a free form patterning topography is selected to facilitate the endothelialization of the outer surface of the inflow cannula (IC) of a commercial VAD. An endothelialization protocol for convoluted surfaces such as the IC is produced, and the retainment of the endothelial cell (EC) monolayer is evaluated. To allow this evaluation, a dedicated experimental setup is developed to simulate realistic flow phenomena inside an artificial, beating heart phantom with a VAD implanted on its apex. The procedural steps of mounting the system result to the impairment of the EC monolayer, which is further compromised by the developed flow and pressure conditions, as well as by the contact with the moving inner structures of the heart phantom. Importantly, the EC monolayer is better maintained in the lower part of the IC, which is more susceptible to thrombus formation and may therefore aid in minimizing the hemocompatibility related adverse events after the VAD implantation.
  • CSFsim: A Simulation Framework for Cerebrospinal Fluid Dynamics and Hydrocephalus Shunt Systems
    Item type: Conference Paper
    Ohnemus, Jonas; Flürenbrock, Fabian; Podgoršak, Anthony; et al. (2025)
    This paper introduces a unified and open-source simulation framework for lumped-parameter models of cerebrospinal fluid (CSF) dynamics and hydrocephalus shunt systems. The framework enables the estimation of the underlying parameters of CSF models from physiological time series data to create a subject-specific model. A synthetic forcing generator is used to create customizable but realistic cardiovascular forcing signals as inputs to CSF models. Additionally, shunt systems with different physical properties and control strategies can be designed and integrated for closed-loop shunt simulations. The framework is based on a modular design, which allows for seamless adaptation and continuous improvement of the individual components in the simulation pipeline. To promote reproducibility and collaboration, we open-source the framework and provide the code at: https://gitlab.ethz.ch/ics/csfsim.
  • Does Size Matter for Female Continuous-flow LVAD Recipients? A Translational Approach to a Decade Long Question
    Item type: Journal Article
    Dual, Seraina A.; Nayak, Aditi; Hu, Yingtian; et al. (2022)
    ASAIO Journal
    Females have increased risk of right-ventricular failure (RVF) and 3 month mortality after left-ventricular assist device (LVAD) implantation. In this translational study, we tested the hypothesis that sex differences in outcomes are driven by pump-induced LV size-volume mismatch, due to a negative impact on interventricular septal (IVS) interdependence. Adult continuous-flow LVAD recipients from the International Society For Heart And Lung Transplantation Mechanically Assisted Circulatory Support registry (n = 15,498) were studied to determine association of female sex with outcomes of 3 month mortality and RVF. Female sex was associated with smaller preimplant left-ventricular end-diastolic diameter (6.5 vs. 6.9 cm, p < 0.001), increased 3 month mortality (odds ratio [OR]: 1.42, p < 0.001) and RVF (OR: 1.18, p = 0.005). Smaller left-ventricular end-diastolic diameter was associated with worse outcomes after LVAD implantation (OR for mortality: 1.20, p < 0.001; RVF: 1.09, p < 0.001), and attenuated the association of female sex with these outcomes. In test bench heart phantoms (n = 4), the IVSs of smaller hearts demonstrated abnormal leftward shift earlier than larger hearts (volume change at IVS shift: 40 [95% confidence interval: 30–52] vs. 50 [95% confidence interval: 48–69] ml). Smaller LV size partially mediates worse post-LVAD outcomes for female patients, due to lower volume thresholds for adverse IVS shifting.
  • Respiratory motion prediction filters for real time tumor tracking during radiation treatment
    Item type: Conference Poster
    Jöhl, Alexander; Schmid Daners, Marianne; Ehrbar, Stefanie; et al. (2015)
    Radiotherapy & Oncology
  • Control of the fluid viscosity in a mock circulation
    Item type: Journal Article
    Boës, Stefan; Ochsner, Gregor; Amacher, Raffael; et al. (2018)
    Artificial Organs
  • Craniospinal Pressure–Volume Dynamics in Phantom Models
    Item type: Journal Article
    Schmid Daners, Marianne; Bottan, Simone; Guzzella, Lino; et al. (2012)
    IEEE Transactions on Biomedical Engineering
  • The Depolarization Amplitude of the Electromyogram is a Measure of End-Diastolic Ventricular Volume
    Item type: Other Journal Item
    Dual, Seraina A.; Hall, S.; Sauer, Mareike; et al. (2020)
    The Journal of Heart and Lung Transplantation
  • Building an interdisciplinary program of cardiovascular research at the Swiss Federal Institute of Technology– the ETHeart story
    Item type: Journal Article
    Kourouklis, Andreas P.; Wu, Xi; Geyer, Robin C.; et al. (2022)
    iScience
    In this backstory, researchers from Swiss Federal Institute of Technology (ETH Zurich) who initiated an interdisciplinary program to generate innovative solutions for different cardiovascular diseases, such as myocardial infarction, valvular replacement, and movement-based rehabilitation therapy, discuss the benefits and challenges of interdisciplinary research.
  • The Effect of Preload Change on QRS Amplitude in Advanced Heart Failure Patients
    Item type: Other Journal Item
    Pergantis, Panagiotis; Dual, Seraina A.; Schmid Daners, Marianne; et al. (2019)
    The Journal of Heart and Lung Transplantation
Publications 1 - 10 of 158