Research suggests that people who exercise for a few hours each week can enlarge their hearts and can be misdiagnosed with heart disease. It is thus important for doctors to consider an individual's physical activity level before diagnosing common heart conditions. The findings are published in Circulation: Cardiovascular Imaging.
The hearts of athletes tend to adapt in response to exercise. This is often called "athlete's heart". A new study shows that healthy adults who exercise regularly may also develop enlarged heart. More than 1000 people were included in this study. All participants were asked to select one of four possible categories that best described their activity level over the past year based on the number of hours they exercised each week.
Approximately one third of participants exercised three to five hours a week and the study showed that one in five of these people had developed an enlarged heart. Similar results were seen in nearly half of those who exercised more than five hours a week.
Study findings thus show that over a threshold of three hours a week, the more you exercise, the more your heart is likely to adapt and the more pronounced the changes on your heart. As Declan O’Regan, of the MRC Clinical Sciences Centre, based at Imperial College London, and one of the lead scientists on the research explains, "Going to the gym frequently increases the thickness of your heart muscle and the volume of your heart chambers, particularly the right ventricle. It’s a completely normal, healthy response. It shouldn’t be misdiagnosed as being heart disease."
Dr Noel Faherty, Research Advisor at the British Heart Foundation, which helped fund the research, said, “Detectable changes to the heart on an MRI scan are common in elite endurance athletes but some heart conditions, like cardiomyopathy, can be diagnosed by detecting similar changes. This study demonstrates the importance of documenting the MRI appearance of healthy, active people’s hearts so normal adaptive changes are recognised by doctors and not mistaken for disease.”
Doctors around the globe use changes in the heart's thickness and volume to determine if the person's heart is healthy or not. But according to the study authors, the normal ranges that have been established to date are based on people who were mainly sedentary. There is now a need to incorporate the role of exercise in this scenario and to update the thickness and volume ranges accordingly. Just like doctors consider factors such as age, height and gender, they should also take into account a person's activity level.
Source: Circulation: Cardiovascular Imaging
Image Credit: MRC Clinical Sciences Centre