Dr Melanie Hezzell – Senior Lecturer in Cardiology, University of Bristol

What or who inspired you to become a vet?

I wanted to be a vet from such a young age that it’s hard to remember a time when it wasn’t my ambition. However, my main motivator was to find an intellectually stimulating job which involved working with horses.  I certainly never imagined that I would eventually become a veterinary cardiologist!

What is your current job? Do you hold clinics as well as carrying out research?

I’m currently a Senior Lecturer in Cardiology at Bristol Veterinary School and divide my time between clinical work for the Langford Vets Cardiology Service, research and teaching. This means I always have lots of plates spinning, but every day is different and I definitely don’t have time to become bored!

What drew you to your field of study and what motivates you to continue?

My interest in cardiology really developed during my time in general practice when I studied for the old-style RCVS Certificate in Veterinary Cardiology. Naturally, I saw a lot of dogs with myxomatous mitral valve disease (MMVD) and I realised that the majority of the management of these patients takes place in primary care practice. MMVD is so common that it inevitably has a significant impact on many of our patients’ quality of life and longevity. It became clear to me that research focussed on practical measures to facilitate optimal care in the primary care setting had the potential to improve the lives of an enormous number of dogs and their owners. My main motivation for continuing is that there is still lots of work to be done!  However, it certainly helps that I enjoy the process – I particularly enjoy statistical analysis (although many people find that odd!).

Discuss the impact your research has had on the profession. How have those in general or referral practice benefited from your research?

I would feel very uncomfortable describing anything as “my research”, as every project I have participated in has been a collaborative, team effort. Additionally, many of my co-authors have been supervisors and mentors, without whom I wouldn’t have developed the research skills I am continuing to acquire; the great thing about my job is that every day is a school day. However, a linking thread running through the research I have been involved in has been the clinical usefulness of plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) in dogs and cats, which has led to the publication of 11 manuscripts in this area. We have investigated its usefulness in differentiating cardiac from non-cardiac causes of dyspnoea in both dogs and cats, its prognostic value in MMVD and its potential to monitor response to treatment in congestive heart failure. Most recently we have derived a new reference interval for NT-proBNP in Labrador retrievers, as normal values are much higher in this breed. My goal has always been to show how biomarkers such as NT-proBNP can be used to aid diagnosis, guide treatment and provide prognostic information for anyone managing dogs and cats with heart disease, but especially those in general practice.

Has your research served as the foundation for other studies or developments in the field, and what will happen after your study is complete?

PetSavers recently funded a study to investigate genes and pathways in MMVD in cavalier King Charles spaniels using a whole genome sequencing approach. The results of this study have been used to design a larger follow-on study which is currently in progress; I’m really excited to see what the results of this study will be.

Tell us a little about your own experience. What does your research mean to you personally and what have you gained from it?

I really enjoyed the research projects I undertook as a veterinary student, but it wasn’t until I started my PhD that I really got the bug.  Having the time and space to learn research techniques while being surrounded by an incredibly supportive group of like-minded people was a huge privilege. Although we no longer all work together, we remain in regular contact and continue to support each other and collaborate on research projects.  Having found learning medical statistics something of a chore as a student, I was surprised to find the process of analysing my own data exciting. Our brains are predisposed to assign meaning to coincidences; this means that it is very easy for us to draw inaccurate conclusions about cause and effect (as a new graduate on call I was convinced I could make my pager go off by running a bath!).  Collecting large enough datasets and analysing them appropriately helps prevent us from making these mistakes and thereby improves our clinical practice. Finally, research has broadened my horizons and allowed me to travel to present my findings at conferences all over Europe and North America (although first I had to overcome my fear of public speaking!).

What is your favourite aspect of your work, and what has been your most important/surprising finding?

Fundamentally, improving patient care is my main motivation, both for research and teaching. Although my contributions to the knowledge base are relatively small and iterative, when taken together over the course of my career I hope that they will eventually add up to something more substantial; at this stage it’s difficult to identify a single most important finding. Perhaps the most surprising finding to date was how accurately emergency and critical care clinicians were able to differentiate cardiac from non-cardiac causes of dyspnoea on the basis of the history and physical examination alone.  Our studies aimed to assess the usefulness of focussed cardiac ultrasound and plasma NT-proBNP, but the clinicians were correct without these test results in about 75% of cases! I also love to see the expression on a student’s face when they make a breakthrough and understand a concept that they previously found challenging; that makes teaching incredibly rewarding.

What does PetSavers offer the profession in your opinion?

PetSavers provides really valuable opportunities for the profession to get involved in research in a variety of ways. I have been lucky enough to receive funding from all the schemes offered by PetSavers and so have a good overview of what there is on offer. A Student Research Project grant was a great way for one of our final year students to gain more research and laboratory skills investigating endothelial damage in MMVD. I’m currently supervising a recent graduate for a Master’s Degree by Research, investigating endothelial damage in cats with cardiac and/or renal disease. This MSc project has given a vet the rare opportunity to work in a cutting-edge laboratory at Bristol Medical School while conducting clinically relevant veterinary research; this would be very difficult to achieve without PetSavers’ support. Finally, the Clinical Research Project grants provide much needed funding to answer important clinical research questions. As well as the project investigating the genetics of MMVD in dogs, PetSavers is supporting one of our residents to investigate cardiorenal syndrome in cats, plus another project investigating arrhythmogenic right ventricular cardiomyopathy in boxer dogs. These opportunities are open to the whole profession, not just those of us working in Universities or referral practice; I would encourage anyone interested to get involved!

Away from the practice and bench, how do you spend your spare time?

Unfortunately, I’m not currently able to do many of the activities I enjoy, such as sailing, SCUBA diving and riding, due to COVID-19 restrictions. However, this has allowed me to spend more time with our small flock of Jacob sheep, add cider apples trees to the orchard and plant more vegetables than we can possibly hope to eat!

What advice would you give to vets considering carrying out clinical research for the first time?

Find a mentor who has experience of clinical research and study design to help you from the outset.  It would be incredibly frustrating and demoralising to realise part way through data collection that the study design is fundamentally flawed and that you won’t be able to answer your clinical question. There are lots of people out there who are able to help – and if they are too busy, they may well be able to help you find someone else, so don’t be afraid to ask.  A mentor can also help you to be realistic about what you are likely to be able to achieve; it’s very easy to be carried away by enthusiasm and design a study that is far too ambitious.  Additionally, it’s important to remember that no-one has yet been able to carry out a perfect clinical study; getting the balance between ideal and realistic study design right (and accepting that it won’t be perfect) is key.