A prevalence of left atrial fibrosis in endurance athletes could explain their increased risk for arrhythmias like atrial fibrillation (AFib), according to data presented this week at the European Society of Cardiology (ESC) Congress in Munich.
The study, which enrolled 16 endurance athletes and 20 non-athletes recruited during routine colonoscopies, delved into the connection between fibrosis and the high incidence of arrhythmias in otherwise healthy long-distance athletes. While moderate exercise is well-known to reduce the risk of cardiovascular disease in the general population, study leader David Peritz, MD, of the University of Utah in Salt Lake City, said in a release, there’s also concern that professional athletes could develop training-related heart injuries.
Athletic activity modifies the heart in ways that are predictable, Peritz said, including structural, functional and electrical changes. His team focused on the electrical angle, because endurance athletes have been linked to a five-fold increased risk of developing AFib.
Peritz said his team recruited athletes who were at least 35 years old, were currently training in endurance sports for at least 10 hours a week and had been competing in the field for at least a decade. The researchers evaluated all participants with late gadolinium enhancement magnetic resonance imaging, and individuals were also asked to complete questionnaires about their medical and activity histories.
Results found athletes to be younger and have a lower BMI than the control group, but they also carried a mean left atrial fibrosis score of 13.7 percent, compared to 11.8 percent in the non-athlete group.
“Despite being younger and having fewer comorbidities, endurance athletes showed more left atrial fibrosis,” Peritz said in a release from ESC. “This was a small study and the clinical significance deserves further investigation, but we think that increased left atrial fibrosis may help explain the higher incidence of atrial fibrillation in endurance athletes. The next step in our research is to see whether the degree of left atrial fibrosis is related to the amount of endurance training.”
He said being an endurance athlete had more of an impact on the degree of fibrosis than any other comorbidities, including diabetes, hypertension and smoking.
“Left atrial fibrosis could be the link between endurance training and risk of atrial fibrillation,” he said. “Ultimately, we hope to use the degree of left atrial fibrosis to help predict how likely it is that an endurance athlete will develop atrial fibrillation, providing an opportunity for prevention.”
After graduating from Indiana University-Bloomington with a bachelor’s in journalism, Anicka joined TriMed’s Chicago team in 2017 covering cardiology. Close to her heart is long-form journalism, Pilot G-2 pens, dark chocolate and her dog Harper Lee.