Having grown up and studied medicine in Rome, Matteo Tozzi is currently deputy head of the Department of Medicine and Surgery, and associate professor of vascular surgery, at the University of Insubria in Varese, Italy. His work within the vascular access field has led to his involvement in numerous significant research endeavours over the past decade, including as a leading investigator for the Lutonix Global AV Registry (BD), the multicentre TreSTAR registry and, most recently, a first-in-human study evaluating the Axess haemodialysis access graft (Xeltis). Here, Tozzi discusses his career so far, and provides perspectives on exciting developments and unmet needs in vascular access care, with Renal Interventions.
What initially attracted you to medicine, and the fields of vascular surgery and vascular access in particular?
The hands-on nature of vascular surgery required to reconstruct conduits, like a plumber, and the myriad of treatments possible from peripheral arteries to central veins, fascinated me from the very beginning, during my first years of medical school. In 2006, I started my career in kidney transplant surgery, and the transition to vascular access surgery shortly followed this. Since then, I have been passionate about this chapter of surgery and its evolution, based on technique, haemodynamics, and technology. The creation and maintenance of vascular access is fundamental to the life of the end-stage kidney disease (ESKD) patient; the satisfaction you get from participating in this process is high. This is the dream that I am always trying to achieve.
Who have your mentors been and how have they impacted your career?
I have had many mentors and each of them has inspired me during my surgical journey. Certainly, Patrizio Castelli has been the mentor who has allowed me to develop and cultivate my interests in the field of vascular surgery. I have him to thank for my involvement in kidney transplant surgery and then in vascular access surgery as well. Surgery is based on a continuous evolution and this characteristic is founded on mentors capable of teaching the passion for this discipline.
What do you feel has been the most important development in the field of vascular access surgery during your career?
I believe that the development of early-cannulation graft technology has been one of the biggest developments. If I think about my efforts in the area of vascular access, early cannulation has enabled us to treat more patients with no vessel fit for native access. This contrasts with the constant increase of central venous catheters (CVC) and the dependence on these devices, which will continue into the future. Patients requiring kidney replacement therapy are increasingly elderly and arrive at dialysis after long treatments that often deteriorate the vasculature. The construction of vascular accesses is therefore more and more complex. The study of the chosen surgical technique to create functional grafts with the lowest possible rate of complications, and the study of the most effective maintenance between drug-coated balloons (DCBs) and stent grafts, has filled these last 15 years of my career.
In light of the various clinical data that have emerged in recent years, how would you assess the current landscape regarding DCBs and dialysis access?
The pathophysiology of intimal hyperplasia is one of the bases for understanding the high rate of reinterventions that our accesses require. Multifactorial genesis makes its treatment complex, but the advent of DCBs is definitely a milestone for the treatment of vascular access stenosis. After the storm that hit antiproliferative therapy, surrounding paclitaxel, we now have more knowledge about its safety. At least two randomised trials now give us a level of evidence of superiority in their use for treatment, with a reduction in the number of treatments to maintain circuit patency and a statistically significant target-lesion primary patency (TLPP) compared to treatment with simple angioplasty. It is now time to consistently use them as a first-line treatment. We are also currently conducting a study of paclitaxel measurement in the blood of patients undergoing DCB treatment—evaluated by high-pressure liquid chromatography (HPLC). The preliminary results are very interesting and I hope the publication will finally put an eternal end to doubts of paclitaxel-induced complications.
As guidelines shift from ‘fistula first’ towards simply ‘the right access’, what do you think is the future role of arteriovenous grafts?
The arteriovenous graft (AVG) has two important applications in the world of vascular access today: in patients with vessels not suitable for native vascular access creation, and in patients with a high risk of maturation failure. Prosthetic access in these patients reduces morbidity and is more cost-effective than the use of a CVC. Today, grafts are a resource to be cultivated to reduce CVC dependence for those patients with poor vasculature. Often, in these patients, it is possible to take advantage of the maturation of the venous outflow and, the second time around, perform a shift to native access; this bridge-to-native modality is my favourite with early-cannulation grafts. The early-cannulation graft often helps me to create an access without having to use CVCs in young crashlanders.
How has the COVID-19 pandemic impacted dialysis patients requiring vascular access care—in Italy, but also across Europe more broadly?
The COVID-19 pandemic has created enormous problems for haemodialysis patients, with a major increase in morbidity and mortality. Varese, the city where I work, has been affected severely by COVID-19, and hospital activity has changed consequently. The reduced possibility of creating vascular accesses and of managing the associated complications has increased the rate of thrombosis and access abandonment, and has increased the percentage of CVCs being used too. An important factor during the upcoming waves of the pandemic are the endovascular methods that could help us in increasing native fistulas. I believe that, today, our responsibility is to reverse this trend by utilising all of the available new technologies and harnessing everyone’s dedication to recover the lost time.
What is the most interesting piece of research in vascular access surgery you have seen over the past year?
The development and the beginning of the use of prostheses based on a futuristic process called endogenous tissue restoration (ETR)—a synthetic matrix that, once implanted in humans, can degrade and be replaced by living tissue created from the patient’s own cells—definitely represents my main interest over the past year. The ability to reduce some typical graft complications, such as infection or cannulation depletion rates, by this process will be critical for our patients in the future. They will be the beneficiaries of futuristic prostheses that combine the benefits of synthetic grafts with those of native vessels.
What is the most significant unmet need within the wider kidney care field right now?
I believe that effective treatment of diabetic nephropathy is sorely lacking in the chronic kidney disease (CKD) landscape today. Diabetes represents an emergency in the Western world and, with it, the worst complications it causes: the diabetic foot and nephropathy. To date, the prevention or treatment of complications are our only weapons and, unfortunately—with regard to kidney damage—we are defenseless.
Looking back over your career, could you describe one particularly memorable case or patient, and why it has stuck with you?
I do not think it is possible to choose one single case, as each of them has left me with something positive, and for that I thank them. Resilience and the determination to live are the best lessons that have been passed on to me. I aspire to continue this adventure with my patients and hope to have given them something positive as well.
What advice would you give to people embarking on a career in the field of vascular surgery?
I think I am lucky, because I chose to be a vascular surgeon early in medical school. I believe that the desire to continue to learn and a certain spirit of sacrifice for the many hours spent in the operating room or angiography suite, in order to learn the basics, is essential. But, today, I tell students and my trainees that vascular surgery can be a very fascinating world to dive into with great satisfaction!
What are your interests outside of the field of medicine?
My main interests are mountains in all their forms. I love reading books about the history of the conquest of the 8,000 and the Seven Sisters. My free time is dedicated to going to the mountains with my wife—accompanied by our two English bulldogs, Tea and Milly (very lazy!). Fly fishing is my other passion, as it allows me to relax completely, and I find the river water cathartic.
- 2006–present: Clinical lecturer of Vascular Surgery, University of Insubria, Varese, Italy
- 2014–present: Associate professor of Vascular Surgery, University of Insubria
- 2022–present: Deputy head, Department of Medicine and Surgery, University of Insubria
- 2001: Degree in Medicine and Surgery, University “La Sapienza” of Rome, Italy
- 2006: Specialisation in Vascular Surgery, University of Insubria
- 2020: National Scientific Qualification of professor of Vascular Surgery, Abilitazione Scientifica Nazionale (ASN)
- 2017: Member of council board, Vascular Access Society (VAS)
- 2020: Principal investigator, TreSTAR registry
- 2021: Principal investigator at study site, first-in-human Axess study
- Member, Società Italiana di Chirurgia Vascolare ed Endovascolare (SICVE)
- Reviewer, International Journal of Surgery, Journal of Nephrology, and Journal of Vascular Access (JVA)