Alexander Zimmermann (University Hospital Zurich, Zurich, Switzerland) tells Vascular News about his career to date, beginning with a rotation in vascular surgery that opened up “a whole new world of medicine” to his directorship of the Department of Vascular Surgery at the University of Zurich. He outlines his current research interests, anticipates how the field might develop in the next decade, and recalls his most memorable case—the first physician-modified fenestrated endovascular aneurysm repair (FEVAR) procedure he ever performed.
Why did you decide to pursue a career in medicine and why, in particular, did you choose to specialise in vascular surgery?
During my childhood, it was always my wish to become an astronaut. This later led to the idea of studying aerospace engineering. However, since I was deployed in the medical service of the German Armed Forces during my compulsory military service after school, I got to know the variety and fulfilment of the medical profession. This is how my enthusiasm for medicine developed, which consequently led to the decision to study medicine instead of aerospace engineering. From the beginning, however, it was clear to me that I wanted to pursue a surgical specialty. This was originally plastic surgery since here one could immediately see the results of one’s manual work. During my residency in plastic surgery, there was a rotation into vascular surgery. Here, a whole new world of medicine suddenly opened up for me. Endovascular therapy, which was still in its infancy at the time, combined with the possibility of open surgical therapy and the higher meaning of the subject, captivated me from the beginning. This led to a change in my career aspirations and the continuation of my specialist training in vascular surgery. A coincidence that I have never regretted to this day.
Who have been your career mentors?
Mentor is a figure from Greek mythology. He stood by Odysseus in word and deed and always gave him courage in difficult situations. Unfortunately, I only had a mentor at the beginning of my clinical career in visceral surgery in Professor Ulrich Fink, who took care of me in word and deed. In the further course of my training, I was unfortunately not granted this good fortune again. This experience gave me the deep desire to be able to act as a mentor for the junior staff working in my department. Whether I succeed in this, however, is a matter for other people to judge.
Nevertheless, some people have had a lasting influence on my path. In the field of surgery in general, this was Professor Jörg Rüdiger Siewert. His visionary thinking and high level of organisation were very impressive. In vascular medicine, Stéphan Haulon, Tim Resch, and Eric Verhoeven are inspiring personalities for me.
What has been the most important development in vascular surgery during your career?
I started my clinical career in early 2000 when endovascular aortic therapy began to be available nationwide in major vascular surgery centres. The development of this form of therapy still leaves me speechless today. Whereas in the early 2000s conventional EVAR was still considered a complex endovascular aortic procedure, these procedures are now performed percutaneously and on an outpatient basis. In this context, I have been particularly fascinated by two developments: first, the development of off-the-shelf thoracoabdominal stent grafts, which are immediately available to patients in urgent cases and emergencies, thereby providing access to therapy to a much larger patient population due to the fact they are far less invasive. In this context, I would also like to mention physician-modified stent grafts, as these continue to inspire me with their variability in application.
What has been the biggest disappointment? Something you hoped would change practice but did not?
So-called endovascular aortic sealing (EVAS). When this technique came on the market, I was initially very excited. The clarity of the logic of lining the perfused portion of the aneurysm through a polymeric sac seemed so simple and promising to me that I wondered why no one had come up with this idea before. In my initial enthusiasm, I thought that this would eliminate the problem of endoleaks. I am convinced that the combination of soft thrombus and rigid embolisation material, unfortunately, cannot form a stable unit and therefore is also the problem in embolisation of type II endoleaks in aneurysm sacs with thrombus.
How do you anticipate the field might change in the next decade, and what development would you most like to see realised?
Technical advancements in the field of open surgical and endovascular medicine will only be marginal in the future. Here, it is still possible to achieve better postoperative results by improving technical skills and materials. Nevertheless, I think the real developments will be in other areas. Through capabilities like artificial intelligence, we will be able to make more accurate predictions about risk stratification. Prevention will also play an important role, as the expanding costs of increasingly complex therapies will not be covered by healthcare systems in the future. Also, the possibility of locally applied drugs for aortic aneurysms, as already successfully practised with the drug-eluting balloon technique in peripheral arteries, will fundamentally change the way we treat this disease.
What are the biggest challenges currently facing vascular surgery?
In the treatment of aortic aneurysm, I still see a big problem in the correct indication. If you imagine that nowadays, despite the technical possibilities, only the maximum diameter is used as a parameter for the evaluation of a therapy indication, this seems almost grotesque.
Another important point for me is to make endovascular therapy more durable. Despite the almost inflationary use of endovascular therapy in the area of peripheral arteries and the aorta, we have not yet been able to achieve durability comparable to that of open surgical therapy. On the one hand, this poses a problem in the area of increased revision rates and the associated socioeconomic costs. Secondly, this has of course a negative impact on the training of the next generation of vascular surgeons. Since simpler pathologies are nowadays almost exclusively treated by endovascular means, these procedures are missing during open surgical training. The open surgeries still performed today are mostly for highly complex cases that cannot serve as training cases.
What are your current areas of research?
Currently, I am working on two main scientific topics. One question that concerns me is what defines the success of endovascular therapy. Why is there a shrinkage of the aneurysm sac in one patient and not in the other, although both have similar morphological preconditions? There are so many aspects that can influence this that I will probably never run out of work and questions. Another focus is aortic dissection. We are currently focusing on the baroreceptors in the aortic arch to gain a better understanding of the blood pressure dysregulation in this disease.
What do you think has been the most important paper published in the last year?
“‘First-in-man’ total percutaneous aortic arch repair with three-inner-branch endografts: a report of two cases” by Stéphan Haulon et al. Even though this is only a case report, the article shows very clearly how far the specialty of vascular surgery has developed and emancipated itself from cardiac surgery.
What has been your most memorable case?
I can remember in detail my first physician-modified FEVAR. This was a multimorbid patient with a contained ruptured mycotic thoracoabdominal aortic aneurysm. I fabricated a two-fold fenestrated and two-fold branched stent graft and was able to implant it without difficulty. The fact that I was able to fabricate a custom-made device within one hour, which often takes companies several weeks, and thus offer a patient this minimally invasive therapy option in an emergency, still excites me today.
What advice would you give to someone looking to start a career in medicine?
Medicine is and will remain an exciting and thrilling profession. In recent years, we have seen a decline in the importance of surgical procedures in favour of drug-based or minimally invasive therapies. As a result, entirely different talents will be required of future physicians. It is always important to remain interested and to consider early on which path your career should take. In addition, you should join a team that supports you in your personal development.
What are your hobbies and interests outside of medicine?
I enjoy spending my remaining time with my family and exploring new cities and countries with them. Currently, I share my eight-year-old son Maxi’s enthusiasm for the ancient Romans and follow their footsteps with him. Otherwise, I love to run in the mountains, especially around Chamonix, as the physical exertion and the grandeur of nature teach you the humility necessary to be successful in our profession. And last but not least, I still feel connected to my Bavarian roots in many ways.