A new study involving 121 former elite rowers from Australia has revealed one in five develops atrial fibrillation (AFib).
This common heart rhythm condition can lead to stroke and heart failure in some individuals, but the researchers identified new genetic and clinical tools that enable early preventive strategies.
Researchers also found the retired rowers, who include former Olympians, are almost seven times more likely to develop AFib than the general population – despite having far fewer AFib risk factors like high blood pressure, diabetes and obesity.
A key finding published in the European Heart Journal was that the likelihood of developing AF was related to not only the effects of a lifetime of exercise training but each athlete's genetic makeup.
Professor André La Gerche, who heads the Heart, Exercise and Research Trials (HEART) Laboratory, which is supported by St Vincent's Institute of Medical Research (SVI) and the Victor Chang Cardiac Research Institute (VCCRI), says the results highlight the paradox that some important heart rhythm conditions are more common among some of the fittest and healthiest in the community.
"This study tells us not to look past the man or woman with the chiselled quads in the doctor's waiting room. Our study proves that AFib is a side effect of endurance exercise, and it can have serious consequences if missed. With the new information that this study brings, AFib can be identified early and treated."
"Some of these athletes had no idea they had AFib until we screened them, as it is a disease that can develop without any outward symptoms," says Professor La Gerche.
About the study
121 former elite rowers aged between 45 and 80 participated in this study. Around 25 percent were women. They underwent state-of-the-art tests to document heart function and rhythm, including MRIs, ECGs, and genetic testing.
Changes to the hearts of elite athletes have been well documented and include enlarged heart chambers and slower heart rates, both of which are healthy adaptive changes.
Professor Diane Fatkin of the Victor Chang Cardiac Research Institute, who undertook the genetic analysis of the athletes alongside Associate Professor Eleni Giannoulatou, says the study also revealed that the risk of AFib extended well after retirement from elite sport.
Professor Fatkin says: " When we followed up on these athletes, we found more cases of AFib had developed. This demonstrates that we need to keep a closer eye on their hearts when they retire and for many years after they stop training."
What's next
Whilst the study has provided valuable new information about elite athletes, questions still need to be answered.
"We need to know how genetic variation increases AFib risk and what factors trigger AFib episodes. We also need to find out whether AFib treatment for elite athletes should differ from the general population," says Professor Fatkin.
Professor La Gerche also stressed the need to maintain perspective: "We shouldn't forget that athletes live healthier lives for longer. This research should not discourage people from sports like rowing. Our job is to make sport safe for everyone and this study is an important advance in heart injury prevention."
