Research Team Looking To Improve Quality Of Care For Heart Surgery Patients
Obesity has long been thought to impact recovery from heart surgery, but traditional measures have been ineffective in predicting outcomes for patients.
That could change thanks to an interesting discovery concerning how one particular protein – GDF15 or Growth Differentiating Factor 15 – relates to the way the immune system deals with injury.
This discovery was made by a research team made up of clinicians, basic scientists, research scholars and data analysts from New Brunswick and Nova Scotia. The team set out looking for anything unique in blood and tissue samples collected from obese patients undergoing heart surgery.
“We were able to identify a subset of patients who are obese who have this particular protein that appears to predict that they don’t do as well after surgery. For some reason, patients that have this protein in a higher level, there is something in their immune system that makes them react a little bit abnormally in a sense that they create more tissue injury rather than repair,” said Dr. Jean-François Légaré, clinical head of cardiac surgery with the New Brunswick Heart Centre and a member of the research team.
“That begins for us this search for an explanation for that at the biological level. Is there something about their genes, is there something about the way their cells respond to injury, is it something different that we could actually target that would actually help them do better?”
As part of the study, the team recruited hundreds of patients at the New Brunswick Heart Centre, but the subset they end up focused on was a smaller study of around 80 patients. From this smaller group, they collected tissue and blood samples at the time of surgery, which they then stored in a biobank.
Using a biobank allowed the team to store tissues in a frozen state for long periods and analyze them at a later date. This was necessary, as not all the patients involved in the study had their surgery at the same time. Rather, they took place over a number of years.
“Also, the knowledge you have tomorrow may be very different than what you have today, so you can actually go back (to these samples) when you have new information or new proteins you can test,” said Dr. Légaré.
The next step for the team is to translate the data they’ve collected and see how it applies to a larger same of people.
“While it is important to identify those 80 patients, it doesn’t mean that it can be validated to everybody. Is it different between men and women, for example. The sample size is too small to tell that. So, we are continuing to build the biobank,” he said, adding that they recently hired a new biobank manager to help them. “We are building that capacity here in New Brunswick and it will be a great resource for information and discovery for the future.”
The research being done by the New Brunswick team is part of a larger study funded by the Canadian Institute of Health Research REACH Program that is looking at inflammation in both arthritis and heart disease. Funding has also come from the Canadian Frailty Network, the New Brunswick Health Research Foundation and the Heart and Stroke Foundation.
Continuing this research is important, said Dr. Légaré, as the knowledge they glean will enable them to advance further and, in turn, help inspire a new generation of investigators to build on that knowledge and push it even further.
Vibrant research is happening in Atlantic Canada, he said, and it is a community of people who are making it happen.
For this project, besides Dr. Légaré, that community includes Shreya Sarkar, who took a lead in the project, as well as Stephanie Legere, Ian Haidl, Jean Marshall, Jeffrey MacLeod, Christie Aguiar, Sohrab Lutchmedial, Ansar Hassan, Keith Brunt, Petra Kienesberger, and Thomas Pulinilkunnil.
“The overall goal is really always to improve the quality of the care we provide and the outcomes for patients,” said Dr. Légaré.
The team’s research has been published in the journal Frontiers in Cardiovascular Medicine.
This story was sponsored by the New Brunswick Health Research Foundation.