In Memoriam Dr Klaus Konner

In Memoriam Dr Klaus Konner

Remembering a Dear Friend, Teacher, Pioneer and Remarkable Human Being

The passing of Dr Klaus Konner leaves a profound sense of loss within the vascular access community. For me personally, however, this loss goes far beyond the passing of one of the great names in our field. I was fortunate to know Klaus as a dear friend, but also as a teacher, a reference point and one of the great pioneers of vascular access medicine. His knowledge, experience and personality had a lasting influence on the way I think about vascular access. He was also a reminder that true expertise does not need to be loud.

For many years, his professional life was closely connected with Merheim Hospital in Cologne. There, he cared for patients referred from across Germany and developed an extraordinary clinical experience in haemodialysis access. His results, particularly with native access in diabetic and elderly patients, helped bring him to the international stage and challenged the widespread belief that these patients should routinely be directed towards prosthetic grafts or catheters.

From 2008 onwards, Klaus Konner was also closely associated with the Departments of Vascular Surgery and Nephrology at University Hospital Cologne. He was one of the few individuals who played a major role in supporting and shaping the development of a structured interdisciplinary approach to vascular access care there from its early stages. His contribution was instrumental in the establishment of the Vascular Access Center at University Hospital Cologne. His experience, his concept of interdisciplinary cooperation and his understanding of long-term access planning had a profound influence on its development.

Klaus Konner's publications – among them Primary vascular access in diabetic patients: an audit, Tailoring the initial vascular access for dialysis patients and History of vascular access for haemodialysis – became landmarks for many colleagues. He participated in international guideline and registry projects and represented German vascular access medicine far beyond national borders. The Lifetime Achievement Award presented to him by the American Society of Diagnostic and Interventional Nephrology in 2025 was therefore not merely an award for a list of publications. It honoured a lifetime devoted to patients, teaching and the advancement of an entire field.

But scientific achievements alone do not explain why he meant so much to so many people. What made Klaus Konner exceptional was the way in which knowledge, experience and personality came together. He was modest, friendly and often quietly humorous. He was close not only to physicians but also to dialysis nurses and all those involved in daily access care. He valued ultrasound, careful clinical examination and the practical knowledge acquired at the patient's bedside.

His lectures were unforgettable. He could lead an audience through decades of vascular access history, combining scientific milestones with personal memories and small anecdotes about the pioneers he had known. He collected publications, illustrations and historical material with remarkable dedication. His presentations often ended with the score of a work by Mozart. From there, he would turn to his image of the nephrologist as the conductor of an orchestra – an orchestra in which surgeons, interventionalists, nurses and dialysis teams all had to listen to one another so that many different voices could ultimately become one coherent whole in the service of the patient.

That image captures much of his philosophy. He never viewed vascular access as the property of a single specialty. He believed in cooperation, mutual respect and long-term responsibility. A Shunt was not simply an anastomosis, a flow measurement or an intervention. It was the patient's lifeline, and every decision had consequences for the years ahead.

Those who spoke with him experienced a man of quiet authority. He could be critical, but never merely dismissive. He asked whether a new technique truly benefited the patient, whether it preserved future options and whether promising short-term results would stand the test of time. His questions were demanding because his standards were high – not for prestige, but for the people whose lives depended on our decisions.

Even in later years, he continued to travel, lecture and share his knowledge with younger colleagues. He gave them access not only to facts, but to the memory of how the field had developed and why certain principles mattered. In this way, he became a bridge between generations.

What I will remember most, however, is not a particular publication, lecture or scientific achievement, but the person behind them: his generosity, his humour, his intellectual honesty and the way he shared his enormous experience with others. Above all, I remain grateful for the privilege of having known him as a friend.

Klaus Konner leaves behind an exceptional scientific legacy. More personally, he leaves behind gratitude: gratitude for his generosity, his humour, his intellectual honesty and his unwavering commitment to patients.

For me, his influence will remain present not only in the literature or in the history of vascular access, but also in my own daily work – whenever I examine a vessel carefully, preserve a future option, discuss a difficult case across disciplines or remember that behind every vascular access is a human being who depends on it.

I will remember Klaus Konner with deep admiration, affection and gratitude – as a dear friend, as a teacher, as a pioneer of our field and, above all, as a remarkable human being.