As a contribution to the FIMH conference, using simulations, we investigated abnormal excitation patterns in the atrium and their electrograms. In contrast to existing studies, we here considered the curvature, different wall thicknesses, as well as electric heterogeneity in a realistic right-atrial geometry.

Extra heartbeats from the main chambers of the heart, so-called ventricular extrasystoles, can be related to serious diseases. Researchers at the Karlsruhe Institute of Technology (KIT) use machine learning to determine the origin of the extrasystoles non-invasively.

Our latest paper describes a methodology to generate anatomical and functional atrial digital twins personalized models from imaging data and/or electroanatomical maps.

The reproducible and automated framework processes geometries derived from clinical data.

The IBT was represented in the tent of the new KIT Center Health Technologies at the Open Day and was happy to welcome many of the about 25,000 visitors about personalized and digital medicine, optical methods in medicine as well as the study course medical engineering.

In cooperation with researchers from the Institute for Medical Informatics and Oral and Maxillofacial Surgery at Heidelberg University Hospital, IBT employees have developed a method to display the 3D geometry of the head as 2D images, which enables a CNN-based classification of head deformities.

The foundation Familie Klee and the German Society for Biomedical Engineering (DGBMT) within the Association for Electrical, Electronic & Information Technologies (VDE) annually give out an award for practically oriented research and development in medical technology. This year’s jury chose Dr.-Ing. Laura Anna Unger and her dissertation on multimodal characterization of the atrial substrate as the winner. Completed with honors at IBT in 2022, the particularly intense collaboration with cardiologists contributed significantly to the success of the project.

The German Research Foundation (DFG) funds the Collaborative Research Center "Wave Phenomena" for 4 more years after intensive review. We are happy to contribute with the use case propagation waves in the heart!

The recently published 2nd edition of the special issue of the journal Frontiers in Physiology highlights the latest developments for technology to diagnose, monitor and treat atrial fibrillation. The collection of 16 articles is co-edited by IBT researcher Axel Loewe.

Assessing the radiosensitivity of tumoral cells is of paramount importance for understanding the efficacy of radiotherapy treatments and design the proper dose delivery scheme. In this work we showed that the topology of 2D cancer-cell graphs is influenced by ionizing radiation and can be capture by microscopy mage analysis.

Following our previous Radiomics based study, we tailored a Deep Learning (3D ResNet) to predict the Overall Survival of patients with PCNSL. The aim was to overcome the limitation of feature selection and engineering by self-learning relevant image features. Gradient-weighted class activation mapping was applied to interpret the results.

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In collaboration with the Biomedical Physics group at the MPI for Dynamics and Self-Organization, we investigated time series of the success rates for cardiac defibrillation. Using a simplified 2D model for chaotic excitation dynamics, we got some interesting insights, especially for the success of low-energy pulses.

In the latest episode of the Signals for Life podcast of the German Society for Biomedical Engineering (DGBMT) in the VDE, Laura Unger from IBT and Armin Luik from the Karlsruhe Municipal Hospital present their joint research on atrial fibrillation. Another episode will follow soon!

Together with researchers from the Università degli Studi di Milano and the Municipal Hospital Karlsruhe, we present a recommendation system for the ablation treatment of atrial flutter. Based on graph theoretic methods, the optimal configuration of the ablation scars to be applied is automatically determined with the help of optimization algorithms.

With the title "Together we are strong! Collaboration between clinicians and engineers as an enabler for better diagnosis and therapy of atrial arrhythmias", a special issue of the journal "Medical & Biological Engineering & Computing" was published that contains works presented at the Atrial Signals conference in Karlsruhe. The editorial furthermore highlights the lifework of Olaf Dössel and Claus Schmitt.

In an invited editorial, Axel Loewe (IBT) and Amir Jadidi (University Heart Center Freiburg Bad Krozingen) discuss the recent article by Boyle et al. in the Journal of Cardiovascular Electrophysiology on predicting the success of pulmonary vein isolation using magnetic resonance imaging.

How do different numerical splitting schemes for solving the monodomain equation of cardiac electrophysiology compare in terms of convergence, accuracy and efficiency? We answer this question collaboratively with mathematicians (CRC 1173 - Wave phenomena) in a study published in the "International Journal of Numerical Methods in Biomedical Engineering".

Together with a team from the University of Szeged, IBT researchers have studied the reverse mode of the sodium-calcium exchanger for the function of the sinus node, the natural pacemaker of the heart. By combining biological experiments and computer simulations, evidence for a crucial role could be demonstrated.

Together with the National Centre for the Replacement, Refinement and Reduction of Animals in Research, the University of Oxford held a symposium on Dec 5 and 6. IBT and its clinical collaborators from Freiburg University presented their work and views on the synergy between computational modeling and machine learning and its clinical translation.

IBT researchers present the first functional 3D computer model of the human sinus node in the renowned Biophysical Journal. 
The structure of this natural pacemaker is crucial for successfully exciting the surrounding heart tissue.

The „Modeling the Cardiac Function“ conference hosted by the iHeart project took place in Cetraro from 30.9 to 2.10. An IBT member was there and presented our studies on the influence of boundary conditions on fluid dynamics simulations.

IBT members and collaborators from the Medical University of Graz investigated if and to what extent simplified methods and models can yield physiologically accurate results in electrophysiological atrial simulations regarding activation times and electrocardiograms (ECG) while reducing computational cost markedly at the same time. These analyses form the basis for extensive ECG-based simulation studies to e.g., generate large-scale datasets for machine learning approaches.

44th International Engineering in Medicine and Biology Conference (EMBC) was held in Glasgow, Scotland,  from 11-15 July 2022.
Four representatives from the Institute of Biomedical Engineering (IBT) participated in EMBC 22, with 3 full paper and one absract presentations.

The machine learning method to predict atrial fibrillation therapy success noninvasively from the ECG is one of the first approaches trained exclusively on data from computational models and benchmarked on real world clinical data.
[report] [paper]

The wish and application of the division and faculty management to appoint the recently retired Prof. Dössel as a Distinguished Senior Fellow was positively approved by the KIT. Prof. Dössel is involved, among other things, in 3 academies of science and in international professional societies as well as an expert in his field of medical technology.
Prof. Dössel and Prof. Ivers-Tiffée are highly regarded in science nationally and internationally and contribute significantly to the visibility of KIT.
Congratulations on these two special awards!

In cooperation with physicians from the St. Anne’s University Hospital, Brno, researchers at IBT showed that a dyssynchronous activation of the left ventricle is insufficient to result in a breakdown of the typical torsional contraction pattern in patients diagnosed with heart failure.

Olaf Dössel was appointed Fellow of the International Union for Physical and Engineering Sciences in Medicine (IUPESM) in recognition of his outstanding contribution to the international development of physical and engineering sciences in medicine.
The IUPESM is the worldwide umbrella organization of all scientific societies for biomedical engineering and medical physics.

Deborah Nairn successfully defended her PhD thesis „Multi-Modality Correspondence to Enhance Arrhythmogenic Atrial Substrate Identification - Guiding Persistent Atrial Fibrillation Ablation Therapy“ on April 14th, 2022.
Our heartfelt congratulations!

Carmen Martinez, scientist in the IBT, presented her research results in the EHRA Congress 2022 poster sessions under the title: “Impact of contact force on local impedance measurements in different atrial locations“. The conference took place in Copenhage between the 3rd and the 5th of April. The scientific program of this year was focused on “Getting back to the rhythm!”, referring also to the recovering of on-site conferences after the pandemic.

Laura Unger successfully defended her PhD thesis „Multimodal Characterization of the Atrial Substrate – Risks and Rewards of Electrogram and Impedance Mapping“ on February 22nd, 2022 and passed the doctoral examination with distinction. Our heartfelt congratulations!

Together with physicians at Freiburg University Hospital, IBT researchers present a method to non-invasively identify those atrial fibrillation patients at increased risk of heart failure. The method is based on machine learning on the electrocardiogram.

On April 11th and 12th 2022, the Institute of Biomedical Engineering is hosting a workshop which aims at teaching foundational coding to researchers, open to registration for all KIT members.

In the days of Otto Hahn and Lise Meitner, scientific life was characterized solely by laboratory experiments, observations of nature and theoretical considerations, scientific essays and discourses. What has changed in the last 100 years? Nowadays, there is hardly a field in which research can be carried out without software.

Researchers of the IBT and the ISTM (Institute of Fluid Mechanics, KIT) have implemented a sequential coupling approach and found that the influence of the blood flow only slightly changes the deformation of the heart wall.

The solution of the inverse problem for ECG imaging (ECGI) is prone to detection of artifacts. A team around IBT researcher Steffen Schuler presented a method to avoid line-of-block artifacts to improve ECGI as a noninvasive diagnostic tool.

Using an electromechanical computational model, researchers at IEKM in Freiburg and IBT could quantify the effect that cardiac motion has on the ECG. This work is an important basis for faster ECG simulations in the future.

With the colloquium "Machine Learning for Medicine and the Role of Simulated Data", Dr.-Ing. Axel Loewe qualified as a university lecturer for the field "Modeling and Simulation for Medicine".

Last week, Steffen Schuler from our group successfully defended his thesis “Novel Methods to Incorporate Physiological Prior Knowledge into the Inverse Problem of Electrocardiography” Congratulations to our newest PhD! #phdlife #CardioTwitter.

Claudia Nagel participated at the Cardiac Physiome Workshop and at the annual meeting of the American heart association. She presented her latest results regarding the influence of the ventricular shape on simulated QRS complexes in the ECG and showed that an estimation of the left atrial fibrotic volume fraction based on simulated P waves was possible with an average error of 8.7%.

Olaf Dössel and Claudia Nagel participated in the first international workshop on metrology for virtual measuring instruments. Olaf Dössel held a keynote lecture about digital twins in medicine and Claudia Nagel talked about how fidelity of simulated ECGs can be assessed for a successful and meaningful application of simulated signals to clinical use cases.

The biannual Atrial Signals conference convened at KIT in September. More than 200 experts from both engineering and clinical communities joined discussions and presented the latest research.

We welcome Miriam Weiß as a new research scholarship holder in the group "Optical Technologies in Medicine".

On October 28th and 29th 2021, the Institute of Biomedical Engineering is hosting a workshop which aims at teaching foundational coding to researchers, open to registration for all KIT members.

IAMO Policy Brief 42 focuses on the needs and strategies for sustainable research software practices based on a position paper.

Hypertrophic cardiomyopathy impairs cardiac mechanics but the differential effects of a thicker wall, reduced active force, fiber disarray and increased tissue stiffness are not clear. IBT researchers could elucidate their contribution to deformation, strain, strain rate and wall thickening using a computational model of the heart.

On the 8th of July Ekaterina Kovacheva completed her PhD with the title “Model Based Estimation of the Elastomechanical Properties of the Human Heart.” Congratulations from everyone at IBT.

In cooperation with the IANM (KIT) and the IEKM (University Heart Center Freiburg), researchers at IBT proposed an electro-mechanically coupled computer model of a personalized human heart. The manuscript was published in the Journal Mathematics.

Researchers at IBT investigated how many cameras are needed so that a microsurgical operating channel can be reconstructed as completely as possible in 3D.
The work was published in the Journal of Imaging (MDPI): https://doi.org/10.3390/jimaging7050087

Researchers at IBT investigated whether the amount of diseased fibrotic tissue in the atria can be estimated non-invasively and quantitatively with features extracted from P waves of the 12-lead ECG.
The work was published in the Journal of Clinical Medicine (MDPI).

We welcome Mr. Simon Hoffmann as a research assistant. His work will focus on data processing in ophthalmology.

IBT researcher Giorgio Luongo and colleagues presented a machine learning-based classification of 12-lead ECG to discriminate between patients with pulmonary vein drivers vs. those with extra-pulmonary vein drivers of atrial fibrillation.
The paper is published in the Cardiovascular Digital Health Journal.

KIT's Institute of Biomedical Engineering develops, based on mathematical equations, a computational heart model to enable targeted therapy of cardiac arrhythmias. The model supports medical research and development in the fields of diagnostic and therapeutic approaches.

Researchers at IBT showed that the statistical analysis of cycle lengths during atrial fibrillation allows to estimate refractory periods of the underlying substrate. The study combines a broad set of simulations with clinical acquisitions and was published in Europace EP.

The Paper describes the environment for the development of sustainable research software in Germany, identifies challenges and calls for action.

To the article

IBT researches in collaboration with the University Heart Centre Freiburg have published a paper comparing unipolar and bipolar voltage mapping for localisation of atrial substrate.

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A scientist of the IBT presented and discussed his results on the simulation of the propagation of photons in a blood vessel.

Researches of IBT, together with researchers from Bologna, Milan, and New York, published a review article on the current state of ECG-based potassium and calcium blood concentration measurements.

Publication of the investigation of the discretization error and its reduction in the geodesic length measurement.

Contributions by the university medical center Freiburg and IBT resulted in a paper on the identification of intraatrial arrhythmogenic sources using intracardiac electrogram characteristics.

IBT researchers published two novel methods for a non-invasive atrial flutter characterization together with physicians from the University of Leicester, the ABC Federal University, and the clinicians form the Städtisches Klinikum Karlsruhe in the journal “IEEE Transactions on Biomedical Engineering”. Spatio-temporal recurrence quantification analysis methods were used to characterize and discriminate several atrial flutter mechanisms from the 12-lead ECG in a computational framework. Thanks to these methods, the duration of the invasive atrial mapping and ablation procedure might shorten significantly. The computational study was complemented and fortified by a clinical case used as a proof of concept.

Together with researchers from the University of Szeged, IBT researchers have published a review article on the role of the sodium calcium exchanger for the activity of natural pacemaker cells. These cells are located in the so-called sinus node of the heart and make for the rhythmic beating of our hearts. The review article integrates findings from experimental studies with computational modeling. It was published in the Frontiers in Pharmacology journal and is freely available (open access).

openCARP is an open cardiac electrophysiology simulator for in-silico experiments. Its source code is public and the software is freely available for academic purposes. openCARP is easy to use and offers single cell as well as multiscale simulations from ion channel to organ level. Additionally, openCARP includes a wide variety of functions for pre- and post-processing of data as well as visualization. The python-based CARPutils framework enables the user to develop and share simulation pipelines, i.e. automating in-silico experiments including all modeling/simulation steps.
openCARP is a joint effort of the Medical University of Graz (Gernot Plank), LIRYC Bordeaux (Ed Vigmond), U Freiburg (Gunnar Seemann) and KIT (Axel Loewe).

The sinus node is the natural pacemaker of the heart initiating each heart beat. Its pacemaking function results from the interplay of to cooperating systems: the so-called membrane clock and the calcium clock. The precise role of these two mechanisms is incompletely understood. Together with a group of experimental researchers from Szeged (Hungrary), the Cardiac Modeling group could now further elucidate the role of the calcium clock. A novel pharmacological agent allows to specifically block the sodim-calcium exchanger. IBT researcher could reproduce and further investigate this effect mechanistically in a computational model. By combining experiment and computer simulation, the crucial role of the sodium-calcium exchanger and the interplay with the membrane clock could be consolidated. The study explains how the natural pacemaker of the heart becomes robust and reliable through the interplay of the two systems calcium clock and membrane clock.

Axel Loewe from IBT was invited to present at the 10th "TRM Forum on the Computer Simulation of Cardiac Function“. The meeting brings together leading experts on computational modeling, experimental assessment, and clinical research in the field of cardiac arrhythmias. We contributed to this year’s theme „Towards the Digital Twin“ by presenting work that allows to build a biomechanical twin of an individual patient. In addition, the session "Atrial modeling & experimental data" was chaired by the IBT researcher.

On November 7 and 8, 40 members of the German research software community met at the Robert Koch institute in Berlin to work on a position paper on „Sustainability of Research Software in Germany“. On invitation of the DFG, the topics motivation for and selection of research software, funding, best practices, policies, and infrastructure were discussed. The respective demands, challenges, ideas for solutions were formulated and phrases as central recommendations for decision makers. After internal revision, the document will be made available to the public for discussion as part of the process for position papers of the German Society for Research Software Engineering (deRSE).

On October 8th, approximately 15 freshmen seized the opportunity of getting to know IBT during the institute tour in their orientation week. Presentations on three topics of current interest in biomedical research gave them an outlook to possible fields of application of their studies in electrical engineering and information technology starting this October. The event concluded with live demonstrations of different medical devices.

The VDE "Praxisnetz Digitale Technologien“ and the "Deutsche Gesellschaft für Biomedizinische Technik" (DGBMT) published a future scenario under participation of IBT experts:

„In the year 2035, digital technology and in particular artificial intelligence have overcome most regulatory obstacles. They expanded into virtually all areas of the public health sector and markedly changed the working environment of physicians. Similar to earlier developments in other professions like pilots, physicians experience a symbiotic collaboration with technology in their daily routine...“

Dialysis patients have an unexplained high risk to suffer sudden cardiac death: up to 100x higher than patients with normal kidney function. A simulation study of IBT suggests a potential reason: the natural pacemaker of the heart, the sinus node, reacts very sensitive to changes of the calcium concentration in the blood. In collaboration with researchers in Bologna (Italy), Szeged (Hungary), Monza (Italy), and New York City (USA), we could show that the heart beat slows down upon a decrease of the calcium concentration. In extreme cases, the heart beat stops. As calcium and other ion concentrations (such as potassium) undergo massive fluctuations in dialysis patients, this could be a relevant reason for the extreme risk of sudden cardiac death in these patients.

Ende August fand in Kassel ein dreitägiges Kolloquium der GACM zum Thema „Mechanik“ statt. Auch die Arbeitsgruppe Herzmodellierung war im Rahmen des Minisymposiums „Numerical methods in biomechanics“ vertreten. Der Vortrag mit dem Titel „Estimating Cardiac Active Tension from Wall Motion – The Inverse Problem of Cardiac Mechanics“ vermittelte einen Einblick in den aktuellen Stand der Forschung hinsichtlich der Entwicklung eines Verfahrens zur nichtinvasiven Bestimmung der Kraftentwicklung im menschlichen Herzen.

We welcome Mr. Anees Qumar Abbasi as a research assistant at the Institute of Biomedical Engineering, started at August 1st, 2019.
  As member of the Optics group, his research will focus on developing a marker-free video-based human gait analysis system, under real-world conditions. The idea is to provide a system, which can automatically assess human gait parameters based on self-made smartphone videos. The system should be capable of detecting the relevant gait phases and calculating the crucial gait parameters out of it.  Advanced Machine Learning/Deep Learning methods will be used in order to extract the relevant gait features from the video. These features will be used for better classification of diseased and normal subjects as well as for early diagnosis of any gait related problem and monitoring of patient’s progress.
  Mr. Abbasi has completed his Bachelor’s and Master’s degree in Computer Science at University of Azad Jammu and Kashmir Muzaffarabad, Pakistan.  His research topics were focused on the human gait analysis and time series processing. He has been awarded scholarship for his PhD from DAAD and Higher Education Commission of Pakistan.

The Institute of Biomedical Engineering welcomes Mr. Alexander Anton as a new researcher. He joined the team in September 2019 and his research focus will be on the intraoperative visualization of nerve fibers of the human brain. Due to its birefringent properties, the orientation of nerve fibers can be detected optically using polarized light. The goal of this research is to develop an appropriate polarization-sensitive image capturing and processing system for intraoperative optical fiber tracking. Such a system would be a great advance for neurosurgery and could bring further benefits in the field of intraoperative diagnostics.
  Mr. Anton completed his master studies in medical technology at the University of Stuttgart. His research interests were in the field of optical methods and systems for medical technology as well as in biomechanics and bionics.

Fifteen participants represented the Institute of Biomedical Engineering from July 23rd to 27th 2019 at the 41st International Engineering in Medicine and Biology Conference in Berlin. Eight posters, five oral presentations and numerous session chairmanships showed Karlsruhe to be a strong competence in the field at the conference edition in Germany. Program chair Olaf Dössel gave the meeting a special character. The broad spectrum of discussed topics amongst scientists from all around the world impressed and motivated the delegation of IBT.

The conference took place in June in Sendai City, Japan. The Cardiac Modeling Group of IBT presented their work "The Inverse Problem of Cardiac Mechanics Estimation of Cardiac Active Stress from Endocardial Motion Tracking“ as an invited talk in the minisymposium „Mathematical and Numerical Modeling of the Heart Function“.

The grant committee of the Deutsche Forschungsgemeinschaft (DFG) decided to extend the funding for the collaborative research centre 1173 „wave phenomena: analysis and numerics“ for 4 more years. Together with our mathematics partners, we work on project B7 "Dynamics of electro-cardiac depolarization waves“. An new aspect to be tackled during the second funding period starting in July will be the coupling of the heart’s natural pacemaker, the sinus node, with the surrounding cardiac tissue.

The PhD students Laura Unger and Mark Nothstein from the IBT participated in the annual congress of the German Society for Cardiology (DGK) in Mannheim together with Prof. Olaf Dössel. The pronounced clinical focus of the congress presented a perfect opportunity to gain insight into the open questions and problems of clinicians. While Laura Unger attended several project meetings as part of the congress Mark Nothstein represented the association project (KIT, Universitäts-Herzzentrum Freiburg / Bad Krozingen, Städtisches Klinikum Karlsruhe) with a poster presentation giving him the chance to discuss his approach towards quantifying pathological substrate with the clinical experts in the field. His contribution was selected to be published as an interview on the online platform “esanum”.

Three members of the IBT (Luca Azzolin, Axel Loewe, Giorgio Luongo) participated in the Gordon Research Seminar and Conference on Cardiac Arrhythmia Mechanisms in Lucca (Barga), Italy. They contributed with poster each and discussed their research with other leading experts in various fields connected with heart rhythm disorders: from computational modellers to electrophysiologists and experimentalists. It was a unique opportunity to listen to cutting-edge talks given by outstanding scientists reporting unpublished discoveries. Our member Luca Azzolin had the honour of winning one of the Deutsche Herzstiftung travel grants for his abstract and Axel Loewe co-chaired the Gordon Research Seminar together with Mathilde Rivaud from the Amsterdam Medical Center.

At the international conference SPIE Photonic West in San Francisco, CA, USA Andreas Wachter presents his currents results. The paper "Development of a real-time virtual reality environment for visualization of fully digital microscope datasets” was presented during the poster session.

Axel Loewe was credited during the Honorable Reception of the KIT president for his success in the Gips-Schüle junior scientist award. Around 80 invited guests experienced a 3 hour program together with a gala dinner in the casino of KIT campus north. Besides the presentation of the KIT doctoral prizes, those KIT members who won important prizes and grants were honored.

Researchers at IBT in collaboration with clinicians from Städtisches Klinikum Karlsruhe have developed a method to estimate an individual’s risk to suffer from atrial flutter using computational models. The novel method has lately been published in the journal „Frontiers in Physiology“ and allows to identify all pathways along which atrial flutter can be sustained in a personalized model of the patient. In this way, the effect of therapeutic interventions like catheter ablation or drugs can be assessed in advance.

How does left atrial size affect the electrocardiogram (ECG)? If a robust recognition of left atrial enlargement would be possible using only the ECG, physicians would be provided with a cheap means to identify an important predictor for atrial fibrillation. In an effort to answer this question, scientists of the IBT have designed and performed a study to virtually enlarge the left atrium and simulate the corresponding ECG. Results of this study show how different types and degrees of left atrial enlargement influence the ECG and how they could potentially be detected in clinical practice. A particularly interesting results is that the frequently used clinical marker „PTF-V1“ is rather an indicator for a thicker atrial wall than for an enlarged atrium.

The annual conference of the Society of Biomedical Engineering (DGBMT) 2018 took place in Aachen.
Among a lot of scientific contributions, the IBT was represented with 16 contributions and was one of the strongest groups at the annual conference. Furthermore, Armin Müller and Tamara Wirth won the 7th and 8th prize in the student competition of the DGBMT.

IBT scientists Axel Loewe and Olaf Dössel won the Patient Safety Award (2nd place) together with clinical collaborators from University Heart Center Freiburg-Bad Krozingen. The honored study introduces two novel ECG-based approaches for real-time assessment of success of catheter ablation to terminate perimitral flutter. Perimitral flutter is an atrial arrhythmia, which occurs frequently subsequent to ablation for atrial fibrillation. The methods were thoroughly evaluated using medical engineering simulations and put to test in a clinical study comprising a validation cohort. In the future, the methods can be implemented in clinical mapping devices. The suggested measures to assess success of ablation have great potential to significantly increase patient safety through shorter invasive procedures as well as higher success rates and therefore a smaller number of redo procedures.

Members of IBT presented 3 scientific contributions at the CinC conference in Maastricht, Netherlands. The contribution "Electro-Mechanical Delay in the Human Heart: A Study on a Simple Geometry" was honored with a price for the poster presentation. Furthermore, members of IBT were involved in the organisation of the conference being session chairs and organizers of the hackathon for inverse problem at this conference.

Every spread of electrical excitation in the heart creates a characteristic spatio-temporal pattern of potentials on the surface of the body.
At IBT, a new method for ECG imaging has now been developed, which utilizes this spatio-temporal relationship by representing measured body surface potentials as superposition of basic potential patterns, for which the corresponding excitation pattern is known. The novel method has been published in the journal „Frontiers in Physiology“.
It could be shown that the origin of simulated atrial extrasystoles can be reconstructed more robustly and more accurately from noisy measurement data than with a commonly used reference method.

We would like to welcome Mr. Luca Azzolin as a research assistant at the Institute of Biomedical Engineering, started at July 1st, 2018. Within the framework of the MY-ATRIA Innovative Training Network (ITN), funded by the European Commission’s Horizon 2020 Marie Sklodowska-Curie programme, Mr. Azzolin is working in the cardiac modeling group at IBT at the development of an integrated and personalized computational model of the atria for an efficient ablation therapy for atrial fibrillation. The final expected result will be a tool helping the cardiologist to predict the ablation outcome.

Mr. Azzolin completed his Bachelor’s and Master’s degree in Computational Science and Engineering (Mathematical Engineering) at Politecnico di Milano. His research topics were focused on the electromechanical modelling and computer simulation of the human ventricles.

In 2018, the international conference celebrated its 15th birthday in Magdeburg, Germany. Following the conference series motto “Bringing together international PhD and MD experts”, Yannick Lutz presented his work concerning the development of a numerical model of brain and systemic temperature during local hypothermia for ischemic stroke treatment. The usage of a novel cooling catheter enables the possibility for fast local inducement of therapeutic hypothermia while reducing systemic side effects.

Michael Kircher was awarded the “Best student paper award” of the 19th International Conference on Biomedical Applications of Electrical Impedance Tomography sponsored by the Institute of Physics (IOP) society. The Conference took place in Edinburgh from June 11th to June 13th.

IBT researchers published a novel method for the immediate assessment of successful treatment together with physicians from the University Heart Centre Freiburg · Bad Krozingen in the journal "JACC Clinical Electrophysiology". The ECG-based method is used to evaluate the completeness of an anterior mitral line during ablation for atrial flutter in the left atrium. Thanks to this new method, the duration of the invasive procedure might shorten markedly and the success rate might increase in future. The clinical study was complemented and fortified by computer simulations performed at IBT.

Health care technology and application are focus areas of the Zeiss-KIT joint Robotics Innovation Competition.

Technologies (Health Care)
• Tracking and referencing
• Smart instruments as control module
• Real-time control with sensor feedback
• Reinforcement Learning
 
Application (Health Care)
• Microsurgery, e.g. Resection of tumorous tissue
• Ophtalmology, e.g. Interventions on the retina
• Surgery process, e.g. Recognition of persons, role and situations

Prof. Dr. Olaf Dössel was appointed Fellow of the European Alliance for Medical and Biological Engineering and Science.
In the document it says: „In recognition of distinguished leadership and important contributions to research and advocacy of Medical and Biological Engineering and Science“.
The document was given on the occation of a meeting on 13rd of March 2017 in London.

Atrial tachycardia still poses a major challenge in catheter ablation. Researchers at IBT have developed a method to automatically analyze intracardiac signals leveraging spatio-temporal relationships. Using this method, reentry mechanisms and critical sites in the atria can be automatically identified. Such automatic interpretation of intracardiac mapping data could help to improve the treatment strategy in complex cases of atrial tachycardia. The study was published in the scientific journal "IEEE Transactions on Biomedical Engineering".

IBT researchers have published a commentary on an article recently published in the journal "Frontiers in Physiology". Axel Loewe and Olaf Dössel highlight the achievement of Shim et al., who used computational models to guide cateheter ablation for atrial fibrillation. On the other hand, the commentary points out potential for further optimization of computer-guided personalized therapy. Exploitation of computational models for a better treatment of atrial fibrillation is one of the research focusses at IBT.

Researcher from IBT together with electrophysiologists at Klinikum Karlsruhe have published an paper introducing a novel method to determine the conduction velocity within the heart. The approach is based on triangulation and provides a means to compute the conduction velocity of  cardiac depolarization waves based in intracardiac catheter measurements. Both computer simulations and clinical measurements werd used to validate the novel method.

Together with our collaborators Prof. Schmitt and Dr. Luik from Städtisches Klinikum Karlsruhe, Prof. Dössel discusses cardiac arrhythmias in the show "Klinik Talk". The show is broadcasted on the channel BadenTV and is available online (in German).

Members of IBT presented 8 scientific contributions at the CinC conference in Rennes, France. Two contributions were awarded prizes: The work "ECG as a tool to estimate potassium and calcium concentrations in the extracellular space“ entered the semi-final of the Young Investigators Award. The work "An Interactive Virtual Reality Environment for the Analysis of Clinical Atrial Arrhythmias and Ablation Planning" was honoured with a poster award. Furthermore, members of IBT were involved in the organisation of the conference being session chairs and organisators of the hackathon for inverse problem at this conference.

Sep/01/2017

We welcome Mr. Tobias Gerach as a new member at the Institute of Biomedical Engineering. Inside the framework of the Collaborative Research Centre 1173: Wave phenomena, Mr. Gerach is working with the cardiac modeling group at IBT on the dynamics of electro-cardiac depolarization waves.

Mr. Gerach received his bachelor and master degrees in geophysics from the Karlsruher Institute of Technology. His research topics at the Geophysical Institute were focused on the simulation of seismic wave fields and the full waveform inversion of seismic waves in maritime environments.

Hyperthermia during radiofrequency ablation causes reversible and irreversible changes of the electrophysiological properties of cardiac tissue. In a recent published study, we investigated changes of conduction velocity in rat myocardium under hyperthermic conditions from macroscopic to microscopic scale by using simultaneous optical mapping and a miniaturized electrode array. The findings of this study may be used to develop further computational models of acute ablation lesions.

July/01/2017

The next issue of the journal "Zeitschrift für Medizinische Physik“ features a review article on „Computerized modeling of the human heart“ by Olaf Dössel and Axel Loewe from IBT. The „Forum“ paper summarizes the state-of-the-art regarding modeling of cardiac electrophysiology, elasto-mechanics, fluid dynamics, and the circulatory system. Both the potential and challenges of this complementary research approach are discussed.

27th of April 2017. The Girls’ Day took place and the IBT is pleased to introduce the world of Medical Technologie to the visiting girls. 19 girls signed in for our workshop on „Technology in the Hospital - visualizing heart and lung activities“. Content was the electric-impedancetomography, photoplethysmography and the electrocardiography. The short introduction into the methods and the fellowing experiments resulted in a phenomenal feedback. The active participation in our build-in questions and experiments made it a great and funny event. We’d like to thank the organizers, supporters, participants and we are looking forward to the next Girls’ Day 2018!

The so-called ST segment in the ECG plays an important role with the diagnosis of myocardial infarction. In a recent published study, the influence of different filtering methods on the ST segment in the ECG was analyzed. Realistic, simulated ECGs with a region of infarction und known noise were used for evaluation. It became apparent, that methods can influence the ST segment in such a manner that the diagnostic information can be falsified.

December/23/2016
IBT scientists in collaboration with cardiologists from Lund, Sweden identified mechanisms contributing to the ECG of the atria (P-wave). Results regarding the limited contribution of the left atrium and the influence of the site of earliest activation were published in the renowned journal "Europace“ of the European Society of Cardiology (ESC).

October/06/2016
With 19 participants and 17 scientific contributions, the IBT was one of the strongest groups at the annual meeting of the German Society for Biomedical Engineering (DGBMT). This year’s meeting was held together with the Austrian and Swiss societies in Basel, CH (D-A-CH). Furthermore, Robin Andlauer and Joachim Greiner did win the first and second prize in the student competition.

September/14/2016
IBT’s studies presented at the „Computing in Cardiology“ conference in Vancouver were well received and awarded several prizes. Axel Loewe won the Rosanna Degani Young Investigator Award (YIA) with the paper "Left Atrial Hypertrophy Increases P-Wave Terminal Force Through Amplitude but not Duration“. Moreover, IBT contributions were awarded 2 poster prizes, one YIA semi final participation, and 2 Mortara Fellowships.
 [More] [Conference website]

April/14/2016
The teaching prize of the faculty of electrical engineering and information technology was awarded to Gustavo Lenis (IBT) at the annual ceremony of the KIT for the creation of the video exercises for the class “Lineare Elektrische Netze”. [More]