Leadership Team


Ernest Spitzer, MD

Chief Executive Officer


Dr. Ernest Spitzer, MD, is a cardiologist deeply rooted in cardiovascular research. He joined Cardialysis in 2014. Before becoming the CEO in 2023, he functioned as Supervising Cardiologist, Director of Endpoint Adjudication and Data Monitoring, Medical Director, and Chief Medical Officer. Dr Spitzer’s experience in cardiovascular research has been characterized by international collaboration. He is also a Board Member of the Academic Research Consortium (ARC), the EU-MDR Cardiovascular Collaboratory, and the European Cardiovascular Research Institute (ECRI). He has authored in 80+ articles in peer-reviewed journals and is academically affiliated to the Cardiology department, Thoraxcenter, Erasmus University Medical Center, in Rotterdam, The Netherlands.

Dr. Spitzer graduated summa cum laude at the Catholic University of Saint Mary, Arequipa, Peru. During his medical training, he was a visiting physician at Henry Ford Hospital, Detroit, and Jackson Memorial Hospital, Miami, in the USA. After medical school, he served two years at the Peruvian Armed Forces. He completed his cardiology training at the University Hospital Miguel Servet in Zaragoza, Spain. Subsequently, he was trained in advanced cardiovascular imaging at Vienna General Hospital in Austria, and completed a research fellowship in interventional cardiology at Inselspital in Bern, Switzerland, with a research fellowship grant from the European Association of Percutaneous Cardiovascular Interventions (EAPCI) and the Spanish Society of Cardiology. During his cardiology training, Dr. Spitzer also obtained a master degree in statistics and research methodology in the Autonomous University of Barcelona, Spain.

Claire B. Ren, MD, PhD

Manager Medical Department


Dr. Claire Ben Ren, MD, PhD, is an imaging physician specialized in echocardiography in structural heart disease. She joined Cardialysis in 2014 and functions now as Echo Core Lab Supervisor and Manager Medical Department. She also works in the interventional cardiology department of Thoraxcenter, Erasmus Medical Center, since October 2014. Her specialty relates to intra-procedural TEE guidance of complex structural heart procedures, including tricuspid and mitral TEERs, TMVR, PVL occluding and LAA occluding. Dr Ren has been actively involved in clinical research and trials and has authored more than 60 articles in peer reviewed journals.

Dr. Ren graduated from the West China School of Medicine, Chengdu, China and obtained the PhD diploma in Cardiology at the Thoraxcenter, Erasmus Medical Center with the thesis ‘Advanced 3D Echocardiography’ in 2014.

Frits Kesselring

Chief Financial Officer


During his 30+ years tenure at Cardialysis, Mr. Frits Kesselring has taken many responsibilities that enabled the transformation from a locally oriented Core Lab spun off from the Erasmus Medical Center into the professional and global company it is today. Perhaps most impactful was his key role in setting up the current corporate Group structure, including ECRI, and roll-out of the first major ECRI project, GLOBAL LEADERS. At some point, when the facilities needed fundamental restructuring in order to enhance visibility and connect all co-workers thus far spread over two floors, Frits took project leadership turning a large empty concrete 2600-sqm 6th floor at the Westblaak  Rotterdam into a state-of-the-art facility integrating fit-for-purpose the intimacy of personal spaces with interactive open offices with maximum daylight.

Born in Rotterdam, his no-nonsense, loyal and dedicated attitude just makes things happen. As an explicit supporter of ‘his’ soccer team Sparta, Mr. Kesselring is collaborative and goal-oriented and over the years, he moved from the precise junior accountant of middle-sized companies like Cardialysis, when he just joined from PriceWaterhouseCoopers, into a more visionary financial leader and is the CFO at Cardialysis. He is critical, analytic, yet still helpful and no-nonsense; trusted and reliable when it comes to achieving a fair deal in his current position.

Jacintha Ronden, PhD

Manager Clinical Operations


Dr. Jacintha Ronden, PhD, is at Cardialysis since 1999. She started working as a Clinical Research Associate (CRA), followed by senior CRA, lead CRA and Project Manager of numerous small and large, mostly multi-center international clinical trials (within Pharma, Device, and Core Lab trials). She has had oversight and coordinating roles within the Safety Department, Clinical Events Committees, and Data and Safety Monitoring Boards. Currently she is Manager Clinical Operations, being responsible for the departments of Project Management, Site Management (Clinical Research Associates and Clinical Trial Assistants), and Safety Department, as well as management of the Cardialysis’ extensive European network of international CRA’s.

Dr. Ronden studied Biological Health Sciences at the University of Maastricht, followed by a PhD trajectory at the departments of Biochemistry and Pharmacology, in the field of thrombosis and hemostasis. She fell under the umbrella of the Cardiovascular Research Institute Maastricht (CARIM). In March 1998 she defended her thesis on absorption, tissue distribution and bioactivity of vitamin K and soon thereafter started to work in the field of Clinical Trials.

Dr. Ronden is enthusiastic; positive; structured; organized; reliable; a team player; goal-oriented; co-operative and analytic. Her hobbies include (mountain) hiking, cycling, travelling and music (singing).

Goran Rudez, PhD

Director Innovation and Technology


Dr. Goran Rudez, PhD, is working for Cardialysis since 2010 and has been active within the company in various roles, ranging from business development towards operational excellence. His current position as the Director of Innovation and Technology focusses on the Cardialysis’ processes and computerized systems seeking a best-fit for the current market while remaining efficient and compliant.

Prior to joining Cardialysis, Dr. Rudez has worked over 10 years as a biomedical scientist mainly within the cardiovascular research area. During this period he has obtained his PhD at the Erasmus Medical Center in Rotterdam, the Netherlands in 2009 with the thesis “Role of P2RY12 Gene Variants and Biological Variation in Arterial Thrombosis”.

Anouk Stam

Manager Human Resources


Mrs. Anouk Stam is the Manager HR at Cardialysis. She is responsible for the company’s Human Resources policy which is focused on the people strategy – including recruitment, salary administration, employee and labor relations and total rewards. She is working at Cardialysis since 2006, and fulfilled different functions before she became Manager HRM in 2015 and is part of the Leadership Team of Cardialysis.

In 2004 she became Bachelor of Business Administration by finishing her Bachelor Marketing Management at HES Rotterdam. She always knew she wanted to become an HR Manager but choose for a more general education. Before she joined Cardialysis she came from a commercial function.

Jako Pranger

Manager Quality Assurance


Mr. Jako Pranger has more than 30 years experience in QA Management in the regulated environment. As Manager QA, Mr. Pranger is and has been responsible for compliance to regulatory requirements in numerous organizations. Besides his responsibilities as Manager QA, he is also responsible for Information Security Management and is registered Data Protection Officer.

Mr. Pranger has been involved as national expert in the ISO committee responsible for ISO14155 and was former Board member of the Dutch Association of Research Quality Assurance. As member of the Scientific Advisory Board of the Dutch Lung Foundation Mr. Pranger reviewed numerous study proposals and was together with other board members responsible for awarding research grants.