At the Gebhard Lab, we bring together a diverse and interdisciplinary team of experienced cardiologists, intensivists, oncologists, (molecular) biologists, and imaging experts. We also host a wide range of master and doctoral students with backgrounds in medicine and the life sciences. We commit to providing equal opportunities while training the next generation of clinicians and researchers.

Group Leaders

Cathérine Gebhard, MD, PhD

Senior Physician/Group Leader

Cathérine’s key areas of expertise include cardiac imaging, interventional cardiology as well as basic and transla­tional research in cardiovascular gender medicine. Cathérine studied medicine and obtained her MD degree at the University of Tübingen (DE) and the University of Western Ontario (CA). She completed her training in Internal Medicine and Cardiology in Switzerland and then specialized in Interventional Cardiology and Cardiac Imaging at the Imperial College London (UK) and the Montreal Heart Institute (CA) where she also completed her PhD in molecular imaging. In 2016 she started her own research group as an SNSF Professor at the University of Zurich. In 2022 Catherine took on a new position as an interventional cardiologist and head of the Women's Heart Center at the University Hospital Inselspital Bern, where she currently focuses on implementing gender-specific medicine into clinical routine. 

ORCID 0000-0001-7240-5822

Caroline Gebhard, MD

Senior Physician/Group Leader

Caroline Gebhard is a board-certified intensive care physician and anesthesiologist at the University Hospital and the University of Basel. She studied medicine and obtained her MD degree at the University of Guadalajara (Mexico), the Stellenbosch University (South Africa), and the University of Tübingen (DE) and underwent clinical training in cardiac anesthesiology, echocardiography, and intensive care medicine at the Montreal Heart Institute (CA), the Charité University Hospital Berlin (DE), the Triemli Hospital Zurich (CH) and the University Hospital Basel (CH). During her training, she obtained board certification in advanced adult perioperative transesophageal echocardiography and transthoracic echocardiography. Her research focuses on personalized medicine in intensive care medicine. This includes ultrasound and hemodynamic monitoring, as well as sex and gender differences in the treatment and outcomes of the critically ill.


The Gebhard Group


Ahmed Haider, PhD

Senior Scientist / Radio-Pharmacy

Achi (Ahmed) studied pharmacology and obtained his PhD degree in neuroimaging at the Swiss Federal Institute of Technology Zurich (ETHZ, CH) in 2018. For his work on the early diagnosis of neurodegenerative disorders, Achi was awarded the prestigious ETH Silver Medal. He is a passionate scientist and loves a vigorous scientific exchange. From 2018 to 2021 Achi completed his postdoctoral fellowship in both clinical and experimental imaging in the Gebhard Lab and then moved to Boston, where he worked in the field of radiochemistry at Harvard Medical School/Massachusetts General Hospital. In 2023 he returned to Europe and took on a new position as Senior Scientist at Roche Switzerland in Basel. Achi continues working with the Gebhard Lab, and given his broad expertise and enthusiasm for science, Achi is currently leading several prestigious research projects in the field of PET/MR imaging and Cardiovascular Gender Medicine.

Pubmed   ORCID 0000-0002-5204-4473


Pimrapat Gebert, MPH and PhD


Pimrapat is a biostatistician with over ten years of experience working with both observational and clinical trial data. She joined the Gebhardlab in October 2022 as a part-time biostatistician to support the research team with several clinical projects. She graduated with a bachelor's degree in nursing science and then a master's in public health in biostatistics from Khonkaen University (Thailand). After relocating to Germany, she completed her PhD studies and currently also works at the Institute of Biometry and Clinical Epidemiology at Charité Universitätsmedizin Berlin (Germany).



Atanas Todorov, MD, PhD

Postdoctoral Fellow / Biostatistics

Atanas is a physician scientist with experience in all phases of translation from bench to bedside, including primary in vitro and in vivo models, conceptualization, study design, graft preparation, implantation, and follow-up and data analysis in first-in-man/proof of concept trials in patients. His particular expertise lies in tendon, cartilage and bone biology and regeneration. Throughout his scientific and clinical career, he has become more and more involved in statistical computation and image analysis, leading him to a part-time postdoc in biostatistics in support of the Gebhard Lab team. His other focus is on state-of-the-art digitalization of medical work and healthcare institutions at Arcondis (CH).

Pubmed   ORCID 0000-0002-1225-4302


Nidaa Mikail, MD

MD-PhD Student

Nidaa is a nuclear medicine physician with a keen interest in cardiovascular imaging and always driven to learn new things. The excellent reputation of Uniersity Hospital of Zurich (CH), a stone's throw from his native Alsace, drew him to Zurich. Here, he is currently completing his PhD in our team. After graduating from the medical school of Strasbourg (FR), Nidaa completed his fellowship in Paris at Bichat University Hospital (FR). He then held a position as a senior consultant in both Bichat and Beaujon Hospitals near Paris. When he is in the office, you should never leave a box of sweets within his reach unless you want to get rid of it. In his leisure time, he enjoys music (an oud and guitar aficionado) and learning about the subtle differences between Dativ and Genitiv and between standard and Swiss German.

Pubmed   ORCID 0000-0003-4896-1428


Angela Portmann, M.Sc.

PhD Student

Angela (Angie) holds both B.Sc. and M.Sc. in Biology from Swiss Federal Institute of Technology Zurich (ETHZ, CH). She is currently pursuing her PhD in Biomedicine at the University of Zurich. Her research is focused on the identification of cardiovascular sex determinants for left ventricular hypertrophy and heart failure. She uses state-of-the-art imaging modalities including small animal cardiac Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET). Angela also applies a broad range of molecular biology techniques to assess signal transduction pathways. Outside of the lab, she loves trying new recipes and food in her kitchen. Books are her constant companions and a good book is never missing from her bag.



Valerie Treyer, PhD

Senior scientist, saving angel and all-rounder

Valerie is a neuroscientist and senior scientist at the Department of Nuclear Medicine (USZ, CH) and at the Institute for Regenerative Medicine (UZH, CH). She has been conducting molecular and multimodal neuroimaging studies since 1998 and has strong experience in Magnetic Resonance (MR) and Positron Emission Tomography (PET) imaging technology. Valerie has also set-up and co-authored various imaging studies with colleagues from different areas of expertise ranging from cardiology, oncology to neuroscience. Her current research focus is on healthy aging. Valerie is always thinking outside the box and brings together brain, heart and hand not only in theory but also in practice.

Pubmed   ORCID 0000-0002-4584-3031


Ketina Arslani, MD


Ketina is a board-certified physician in internal medicine and cardiology, with a special interest in interventional cardiology and structural heart disease. During her medical training, she worked at the Department of Cardiology of the University Hospital Basel where she spent also one-year of critical care rotation and one year in clinical cardiovascular research at the Cardiovascular Research Institute Basel (CRIB) funded by the "Young Talents in Clinical Research" grant from the Swiss Academy of Medical Sciences. Ketina started her research and clinical fellowship in Interventional Cardiology at the Rigshospitalet in Copenhagen (Denmark) in 2021 funded by the "Postdoc Mobility" grant from the Swiss National Foundation. Given her interest in sex and gender differences in cardiovascular diseases and intensive care medicine, she is working and collaborating in different projects, including a recently published study on mortality trends in cardio -and neurovascular patients in Switzerland as a first author.



Bianca Gysi, MSc


Bianca graduated from medical school in 2021 at the University of Basel. She joined our research group the same year as a full-time doctoral student. She worked with our team on different research projects during the COVID-19 pandemic, investigating the impact of sex and gender on acute and long-term outcomes of SARS-CoV-2 infection. For her work in this field, she won the best oral presentation award at the Congress of the Swiss Society of Intensive Care Medicine in 2022. Since August 2022 Bianca works as a resident in Internal Medicine at the Bruderholzspital in Basel.



Michael Fiechter, MD, PhD

Clinical Research Fellow

Michael is chief of service and board-certified neurosurgeon specialized in spine surgery and spinal cord surgery at the Swiss Paraplegic Center in Nottwil (CH). He is also a passionate natural scientist. Thanks to his double degree in medicine and natural sciences, Michael combines experimental, translational and clinical research in functional neurovascular imaging to investigate the neuro-hematopoietic-vascular axis and its influence on cardiovascular outcome. Despite his intensive clinical and research commitments, Michael is the father of three lovely children, and has a passion for karate and endurance sports.

Pubmed   ORCID 0000000272930704


Alexander Meisel, MD

Clinical Research Fellow

Alex‘s focus is on oncology, cardio-oncology and cancer imaging. After his medical studies at the Ludwig Maximilian University of Munich (DE), he moved to Zurich to continue his clinical education in Medical Oncology at University Hospital Zurich (CH). Alex has also worked at the Stadtspital Waid as an attending physician and at Swiss Federal Institute of Technology Zurich (ETHZ, CH) to study novel Positron Emission Tomography (PET)-tracers in ovarian and lung cancer. He believes that precision oncology should not just be a long-term dream for the future, but part of the current cutting-edge of medicine. Alex seeks out the best possible treatment options for his patients and passionately implements novel imaging and sequencing techniques into daily clinical practice.

Pubmed   ORCID 0000-0003-2422-1281


Geoffrey Iain Warnock, PhD

Research Fellow / Imaging Specialist

Geoff specializes in quantification of biomedical images and splits his time between industry and academia. He has worked in imaging for nearly 15 years, with experience in both small animals and humans, and now focuses on fully quantitative positron Emission Tomography (PET) with blood-based kinetic modelling. He was involved in the development and evaluation of 18F-UCB-H for synaptic vesicle protein 2A, an exciting new target for imaging neurodegeneration, and more recently in first-in-man studies with 18F-PSS232 for mGluR5. On top of his roles in Bruker’s image analysis software branch PMOD Technologies (CH)and Swisstrace GmbH (CH), Geoff is proud to be part of the Gebhard Lab. Out of the office, Geoff loves to be on the move in the mountains, either mountain biking or ski-touring.



Hazem Ahmed, PhD

Reserach Fellow / Radiopharmacist

Hazem is a pharmacist by training with a background in Quality Management and drug development. He completed his PhD in 2020 at Swiss Federal Institute of Technology Zurich (ETHZ, CH) in Pharmaceutical Sciences with a concentration in Neuroimaging and Radiopharmaceutical Chemistry. His work spanned the fields of basic and applied pharmaceutical sciences from development of new labeling methods of complex biomolecules to brain tracers development and clinical translation. As of now, he joined the GebhardLab as a fellow and is stepping with anticipation into the field of cardiac imaging and clinical studies.

ORCID 0000-0001-7047-5202


Vera Regitz-Zagrosek, MD, PhD

Guest Professor

Vera is the founding director of the Berlin Institute for Gender in Medicine (GIM) at Charité University Medicine (DE). From 2011 to 2018, she was the coordinator for the partner site Berlin in the German Center for Cardiovascular Research (DZHK), a centre of excellence in German cardiovascular research. Her research focusses on sex and gender differences in cardiovascular diseases, in basic and clinical science and public health. She is the founding president of the German and International Society for Gender Medicine, and was twice, in 2012 and 2018, the coordinator for the European Society of Cardiology Guidelines for cardiovascular diseases in pregnancy. In 2018, she received the First-Class Cross of Merit of the Federal Republic of Germany for her achievements in gender medicine. As a pioneer in gender medicine in Germany, Vera advises the Medical Faculty of the University of Zurich (CH) on the implementation of knowledge for sex- and gender-specific differences in medicine. She is currently also a visiting professor and senior consultant at the University of Zurich (CH) where she supports the Gebhard Lab and the implementation of sex- and gender-specific knowledge in research, teaching, and medical practice.

Pubmed   ORCID 0000-0002-3566-3467

Master and Doctoral Students

Denis Bratelj, pract. med.

Medical Doctoral Student

University of Zurich
Thesis project: Spinal cord tethering and syringomyelia after trauma: impact of age and surgical outcome

Magdalena Marggraf

Medical Master Student

University of Basel
Thesis project: Benefit-to-risk balance of coronary angiography in the critically ill

Philip Kaufmann, pract. med.

Medical Doctoral Student

University of Basel
Thesis project: Sex and gender differences in sepsis: Performance of the SOFA score in critically ill men and women.

Isabelle Glarner, pract. med.


University of Zurich
Thesis project: Exploring the Correlation Between Neuronal Stress Response and Coronary Inflammation

Noemi Sablonier, pract. med.


University of Zurich
Thesis project: Exploring the Predictive Value of an Enhanced Amygdalar Activity on Major Adverse Cardiovascular Events in Women and Men

Dominik Sager, pract. med.


University of Zurich
Thesis project: Exploring Predictors of Enhanced Neuronal Stress Responses in Cardiovascular Disease

Claudia Sütsch, pract. med.

Medical Doctoral Student

University of Zurich
Thesis project: Influence of Gender on COVID-19 Disease

Adriana Vinzens

Medical Master Student

University of Zurich
Thesis project: Impact of Perivalvular Inflammation on Long-term Outcomes After Transcatheter Aortic Valve Implantation


Gioia Zoe Epprecht

Medical Master Student

Thesis project: Age- and Sex-dependent Amygdala Metabolic Activity Pattern

Dominik Etter, B.Sc.

Research Assistant

Nik did his Master studies in interdisciplinary natural sciences at the Swiss Federal Institute of Technology Zurich (ETHZ, CH). Niks work is focused on the physical and biological bases of biomedical imaging. As a research assistant at the Gebhard Lab, Nik worked primarily in the field of image evaluation, data collection, and their automation. In his spare time, he is often seen in the kitchen, enjoys reading original science fiction novels and playing speedminton.

Pubmed ORCID 0000-0002-7060-6089

Anna Luisa Beeler

Medical Master Student

Thesis project: Association Between Low-grade Inflammation and Supernormal Left Ventricular Ejection Fraction (snLVEF)

Lilian Mayrhofer, B.Sc.

Research Assistant

Project: Impact of Sex and Gender on COVID-19 Outcomes

Elvira Krämer, M.Sc.

Research Assistent

Project: Impact of Sex and Gender on COVID-19 Outcomes

Mariano Paredes Heck, B.Sc.

Research Assistant

Project: Impact of Sex and Gender on COVID-19 Outcomes

Mina Qadirie, B.Sc.

Research Assistant

Project: Impact of Sex and Gender on COVID-19 Outcomes

Nadia Hamouda, pract. med.

Medical Doctoral Student

Thesis project: Development of a Gender-sensitive Risk Assessment Tool to Predict Short- and Long-term Outcomes of COVID-19

Livia Anna Krüger, B.Sc.

Research Assistant

Project: Impact of Sex and Gender on COVID-19 Outcomes

Núria Zellweger

Research Assistant

Project: Impact of Sex and Gender on COVID-19 Outcomes

Winandus Wijnen, PhD

Postdoctoral Fellow / Writing Specialist

Curiosity drove Wino from an active research career to academic writing and innovation management. Nevertheless, Wino has remained in close contact with the academic world and joined the Gebhard Lab from 2019 to 2021. With his extraordinary wealth of experience from his PhD times – where he studied the molecular mechanisms underlying heart failure as well as inflammatory responses in myocarditis – and his powerful mindset to develop and refine state-of-the-art ideas, and build up manuscripts and proposals, it is not surprising that he has his own successful company WiWright.

Pubmed   ORCID 0000-0002-3513-3618

Flavia Diggelmann, pract. med.

Medical Doctoral Student

Thesis project: Neuronal Stress-Response in Female and Male Patients with Heart Failure

Susan Bengs, PhD

Deputy Group Leader Basic Research and Management

Susan did her B.Sc. in molecular biotechnology and a holds a diploma in biology from the Technical University of Dresden (DE). She then completed her PhD studies in Department of Gastroenterology and Hepatology at the University Hospital Zurich (CH), where she identified biomarkers for early colorectal cancer detection. After her PhD studies, Susan joined the Gebhard Lab in 2018 and was deputy group leader at the Gebhard Lab from 2019 to 2022, where she led research projects, but was also in charge of organizational and administrative tasks and the supervision of young researchers.

Pubmed   ORCID 0000-0003-2424-3894

Marie-Louise Sieber, M.Sc.

Research Assistant

Project: Impact of Sex and Gender on COVID-19 Outcomes

Alexia Rossi, MD, PhD

Deputy Group Leader Clinical Studies

Alexia received her medical degree in 2004 and board certification in diagnostic imaging in 2008 from the University of Trieste (IT). Later, Alexia obtained her PhD in advanced cardiovascular imaging from Erasmus MC University Medical Centre in Rotterdam (NL). Thanks to a training grant from the European Society of Cardiology, she then moved to London where she further specialized in cardiac computed tomography at the Centre for Advanced Cardiovascular Imaging at the Barts Heart Centre (UK). At that time, Alexia was appointed assistant professor in diagnostic imaging at Humanitas University in Milan and returned to Italy. Alexia has consolidated experience in cardiac CT that she not only applies as an as active member of the EACVI Certification and Accreditation Committee, but also as a senior scientist in the Gebhard Lab, where she worked from 2020 to 2023 as a deputy group leader. Alexias research is focused on understanding mechanisms of cardiovascular diseases through novel, non-invasive imaging modalities. Alexia loves travelling, «good» instant coffee, and Christmas time.

Pubmed   ORCID 0000-0001-6845-1199

Karin Peer

Administrative Assistant

Karin worked in industry before starting her position at University of Zurich (CH) in 2019. She supported the Gebhard Lab from 2020 to 2022 as an administrative assistant, enriching the our team with her passion and cordial attitude. In her leisure time, she loves being around her family and friends, outdoor-activities and handicrafts.

Alessia Delcò

Medical Master Student

Thesis project: Long-term Prognostic Value of Enhanced Neuronal Stress Responses in Women and Men with Cardiovascular Disease

Katharina Schade

Medical Master Student

Thesis project: Predictive Value of Myocardial 18F-fluorodeoxyglucose (FDG) Uptake for Diagnosis of Coronary Artery Disease in Patients Undergoing Oncologic Positron Emission Tomography

Chiara Henze

Medical Master Student

Thesis project: Influence of Socio-cultural Gender on the Course of COVID-19

Dominik Etter

Interdisciplinary Bachelor Student

Thesis project: Does Quantification of Fat Attenuation Index add Prognostic Value as an Adjunct to State of the Art Cardiovascular Imaging?

Andrea Roggo

Medical Master Student

Thesis project: Assessment of Osteoporosis Markers and Brain Metabolic Activity as a Sex-specific Approach for Risk Prediction in Women and Men Undergoing Non-invasive Cardiac Imaging

Arnaud Dussault-Cloutier

Medical Master Student

Thesis project: Influence of the Sex Hormones Estrogen and Testosterone on the Course of COVID-19

Sandro Fröhlich, B.Sc.

Pharmacy Master Student

Thesis project: Age-dependent Remodelling of the Female Heart – Protective or Detrimental? Role of Age, Sex Hormones, and Myocardial Infarction on the Cardiac Function and the Expression of Genes Involved in the Remodelling of the Heart

Mina Pasqualini

Medical Master Student

Thesis project: Gender Differences in the Long-term Effects of COVID-19

Monika Marędziak, PhD

Postdoctoral Fellow

Project: Age-dependent Remodelling of the Female Heart – Protective or Detrimental?

Nastaran Sang Bastian

Medical Master Student

Thesis project: Predictors of an Increased Amygdalar Metabolic Activity in Cardiovascular Patients

Dominik Etter


Term paper: Age-dependent Myocardial Fibrotic Remodelling – Evaluation by CMR-derived T1 Mapping

Angela Portmann, B.Sc.

Biological Master Student

Thesis project: Age-dependent Remodelling of the Female Heart – Protective or Detrimental? Exploring the Role of Endocrine Factors and Cardiac Sympathetic Modulation

Muriel Grämer, PhD

Research Fellow / Pharmacy

Muriel studied pharmaceutical sciences at Swiss Federal Institute of Technology Zurich (ETHZ, CH) and obtained her PhD in molecular pharmacology for her research on GPCR-signaling in the context of cardiovascular disease. This was followed by employments in public pharmacies consulting patients and at the Federal Office of Public Health ensuring patient access to affordable pharmaceuticals. Muriel joined the Gebhard Lab as a part-time research fellow from 2020 to 2021. Given her broad expertise she was involved in both preclinical as well as clinical projects to explore the impact of sex and gender on COVID-19.

Nicola Lott, PhD

Research Fellow / Writing Specialist

Nicola studied Biology at the University of Constance (DE) and obtained her PhD in 2011 at the University of Zurich (CH). Her PhD studies were part of a cooperative initiative between the Cardiovascular Research Group and the Institute of Physiology (UZH, CH), allowing her to investigate mechanisms of obesity-induced endothelial dysfunction from different angles. After her PhD, Nicola joined the Hematology Medical Affairs Department of the pharmaceutical company Celgene GmbH (CH). In that time, she obtained a profound expertise in medical writing, coordination of clinical trials as well as development of scientific strategies. Given her expertise in in coordination and medical writing, she worked as a postdoctoral researcher from 2021 to 2022 in the Gebhard Lab, thereby focusing on data analysis and presentation but also manuscript and grant proposal writing.


Christine Lohmann, M.Sc.

Research Coordinator

Project: Age-dependent Remodelling of the Female Heart – Protective or Detrimental?

Niels Kirk, M.Sc.

PhD Student

Thesis project: Age-dependent Remodelling of the Female Heart – Protective or Detrimental? Exploring the Role of Endocrine Factors, Cardiac Sympathetic Modulation, and Gender-specific Behaviours

Yves Gou Pargätzi

Medical Master Student

Thesis project: Association Between Vascular Inflammation and Epicardial Fat Volume in Women

University Hospital Inselspital Bern

Department of Cardiology
Freiburgstrasse 18
CH-3010 Bern

University Hospital Zurich

Department of Nuclear Medicine
Cardiovascular Gender Medicine
Rämistrasse 100
CH-8091 Zurich

University Hospital Basel

Department of Acute Medicine
Intensive Care Unit
Petersgraben 4
CH-4031 Basel