A Tribute to Professor Hans Klaus Breddin

Professor Dr. med., Dr. h. c. Hans Klaus Breddin, was a world-renowned clinician-scientist who was among the pioneers in the field of vascular medicine. He was a true leader who, for over 50 years, provided unending service to the field of vascular medicine, research, education, and public service. Klaus played an important role in our understanding of the pathogenesis of thrombosis and the development of antithrombotic drugs.

Hans Klaus Breddin was born in Cologne, Germany, in 1928 and obtained his degree in medicine at the Ludwig-Maximilians-University Munich in 1952. He established his first Coagulation Laboratory in Aachen in 1954 where he was completing his medical training. In 1957, he joined the Johann-Wolfgang-Goethe University Frankfurt where he quickly established himself as one of the leading clinicians and scientists in Germany in the field of vascular medicine. In 1971, he became the director of the Division of Angiology and was soon promoted to professor of internal medicine. He was among the first to bring the discipline of angiology to its current ranking as a multidisciplinary field that impacts medicine and surgery.

One of Klaus Breddin's early scientific publications in 1957 was on the treatment of myocardial infarction with aspirin (followed by 300 more scientific publications throughout his career). Several other original clinical studies with aspirin were conducted under his expert guidance. Among these was the German-Austrian Aspirin Trial on the secondary prevention of myocardial infarction (Circulation, 1980), which provided important evidence for the beneficial role of aspirin in the treatment of acute coronary syndrome. With his more recent clinical studies, Klaus became one of the pioneering clinical trialists who set new standards for the validation of clinical efficacy and safety of new antithrombotic and antiplatelet drugs (New England Journal of Medicine, 2001; Blood, 2002).

Klaus Breddin's interest in platelet function led to the development of novel laboratory methods. His spontaneous platelet aggregation tests (PAT I, II, and III) that evaluated a rotating blood specimen by either a microscopic or photometric endpoint provided a means to identify hyperaggregation of platelets. Two conclusive clinical studies were published in International Angiology in 1986. Studying the contribution of platelets to thrombin generation led to his development of the platelet-induced thrombin generation time (PITT) test (Haemostasis, 1992). This new method became a useful tool for studying the effect of heparins and other antithrombotic drugs on platelet-induced coagulation activation.

In addition to clinical studies, Klaus Breddin recognized the importance of experimental investigations in antithrombotic drug development. He developed animal models of arterial and venous thrombosis to study the dynamics of thrombus formation mediated by the interactions between platelets and endothelium under blood flow conditions. Of particular importance was the laser-induced thrombosis model (Haemostasis, 1988, 1989) that became a reference method to validate the efficacy of most of the currently used anticoagulant drugs, including new heparins, thrombin inhibitors, and FXa inhibitors in the preclinical setting.

Always a dedicated teacher, Klaus initiated and developed new curricula in vascular medicine and specialty training for young investigators at the University Clinic in Frankfurt. These individuals went on to develop related clinical and research programs throughout the German-speaking European countries, as well as many Eastern European countries. Since 1965, Klaus had promoted and organized a yearly series of Angiological Symposia in Kitzbühel, Austria, to foster knowledge in vascular medicine, with many open discussions on cutting-edge topics such as stroke, coronary syndromes, venous thrombosis, vasculitis, and drug treatment modalities.

Klaus also fostered interactions between academia and industry. He was able to bring together talented scientists and clinicians who worked on the design, development, preclinical validation, and therapeutic introduction of such new drugs as low molecular weight heparins (nadroparin), antiplatelet drugs (clopidogrel), thrombin inhibitors (hirudin, argatroban), and FXa inhibitors (fondaparinux, rivaroxaban). His vision in drug development was far reaching and will continue to impact the future management of vascular diseases.

In 1988, Klaus founded the International Institute of Thrombosis and Vascular Diseases, an organization devoted to fostering basic and applied research in the field of vascular medicine and surgery. This institute provided a platform for scientific, educational, and technical support to various individuals, groups, and regulatory agencies. Dissemination of knowledge through symposia and other programs for clinicians, health-care professionals, and scientists was strongly promoted. The intelligence and rational, clear thinking that was characteristic of Klaus Breddin not only benefited those who directly worked with him but also the public through the creation of expert consensus documents and the decision making of regulatory bodies.

Upon becoming professor emeritus at the University of Frankfurt in 1994, Klaus Breddin continued to pursue his scientific interests with unfailing enthusiasm. He received the Docteur honoris causa from the University of Bialystok in Poland in 1994, an honorary membership in the International Union of Angiology in 1995, and the Médaille of the German Society on Atherosclerosis in 2000.

To the worldwide scientific community engaged in the field of thrombosis and hemostasis, Klaus Breddin was a great mentor and a caring friend. Many respected his scientific insight, creativity, and open-mindedness. He possessed a blend of charm, humanity, and generosity. If not enjoying a scientific discussion with friends and colleagues, Klaus could easily be discussing another of his many interests, including history, archeology, model ship building, model railway building, sailing, travel, photography, or nature, usually over a bottle of German white wine.