Project B10 - Magnetoelectric Sensor Systems for Cardiologic Applications

Current standard electrocardiography is a useful and easily applicable method that has been in clinical use for more than hundred years. However, it is hampered by low spatial resolution. Thus, precise electro-anatomical mapping of arrhythmias still has to be conducted by invasive catheterization. The main long-term objective of this project is to answer the question whether invasive mapping of arrhythmic substrates (current standard) can be replaced by a non-invasive alternative, namely analyses using signals obtained from ME sensors combined with electric measurements.

We will thus investigate if a multi-channel combined ECG/MCG (electrocardiogram/magnetocardiogram) approach allows for reliable non-invasive localization of the origin of cardiac arrhythmias. This is becoming even more important, as recently stereotactic body radiation therapy was successfully applied for ablation of ventricular tachycardia, promising a completely non-invasive way to cure arrhythmias in the future.

To perform the required measurements with a multitude of magnetic (both ME sensors originating from this CRC and already established systems) as well as electric sensors, individual real-time signal-to-noise ratio estimations of all involved sensors will be investigated that permit optimal sensor placement, sensor signal combination, and parameter extraction. An appropriate automatic signal quality analysis should guarantee a minimum recording time for patients. To answer these research questions, forward modelling and a solution of the inverse problem is necessary. Here the results of the former CRC project B3 will be used and further extended. To evaluate the accuracy and clinical utility of this approach, we plan to compare it with results from electrophysiological studies (current standard) in 3 different groups of patients:

  • premature ventricular contractions,
  • idiopathic ventricular tachycardia,
  • ischemic ventricular tachycardia.

For each patient, magnetic resonance imaging (MRI) and computed tomography (CT) for anatomy and electric and magnetic measurements will be performed.

 

Involved Researchers

Person Role
Prof. Dr. Norbert Frey
Medicine
Cardiology (Heidelberg)
Project lead
Prof. Dr.-Ing. Gerhard Schmidt
Electrical Engineering
Digital Signal Processing
Project lead
M.Sc. Erik Engelhardt
Electrical Engineering
Digital Signal Processing and System Theory
Doctoral researcher
M.Sc. Adrian Zaman
Medicine
Cardiology (Kiel)
Medical doctor

 

Role within the Collaborative Research Centre

Close cooperation is planned with the following partners:

Collaborations
A8 (Modelling of Magnetoelectric Sensors) The sensor models that are investigated in A8, will be incorporated in the forward. A first sensor model version available in 2021 will be replaced with extended versions in 2023.
B1, Z2 B10 will benefit from B1 adapting system front-ends and small sensor arrays to the requirements of B10. In turn, we will communicate test results back to B1 to facilitate the development of suit- able measurement systems after transfer of mature sub-systems to Z2.
B2, B9 The project will use the same real-time framework as B2 and B9. Thus, all extensions made in either one of the projects will benefit the other and immediately speed up development.
Z1 (MEMS Magnetoelectric Sensor Fabrication) This project is closely interlinked with the ME sensor projects, especially those that allow for low frequency (5 to 30 Hz) measurements.

 

Project-related Publications

E. Engelhardt, E. Elzenheimer, J. Hoffmann, C. Meledeth, N. Frey, G. Schmidt: Non-Invasive Electroanatomical Mapping: A State-Space Approach for Myocardial Current Density Estimation, Bioengineering, 10(12), 1432, 2023. 
E. Engelhardt, E. Elzenheimer, J. Hoffman, T. Schmidt, A. Zaman, N. Frey, G. Schmidt: A Concept for Myocardial Current Density Estimation with Magnetoelectric Sensors, Current Directions in Biomedical Engineering, vol. 9, no. 1, 89-92, 2023. 
E. Elzenheimer, P. Hayes, L. Thormählen, E. Engelhardt, A. Zaman, E. Quandt, N. Frey, M. Höft, G. Schmidt: Investigation of Converse Magnetoelectric Thin Film Sensors for Magnetocardiography, IEEE Sensors Journal Print ISSN, pp. 5660-5669, 2023. 
E. Engelhardt, A. Zaman, E. Elzenheimer, N. Frey, G. Schmidt: Towards Analytically Computable Quality Classes for MCG Sensor Systems, BMT 2022, Joint Annual Conference of the Austrian, German and Swiss Societies for Biomedical Engineering, 2022. 
E. Elzenheimer, C. Bald, E. Engelhardt, J. Hoffmann, P. Hayes, J. Arbustini, A. Bahr, E. Quandt, M. Höft, G. Schmidt: Quantitative Evaluation for Magnetoelectric Sensor Systems in Biomagnetic Diagnostics, MDPI Sensors, vol. 22, no. 3, 1018, 2022.
C. Enzingmüller, CS. Broß, D. Laumann, I. Parchmann, G. Schmidt: Magnetfelder am Herzen messen, MNU Journal, no. 2, pp. 149-153, 2021.
J. Reermann, E. Elzenheimer, G. Schmidt: Real-Time Biomagnetic Signal Processing for Uncooled Magnetometers in Cardiology, IEEE Sensors Journal, vol. 15, issue 11, pp. 4237-4249, 2019.