Cardiac MRI shows heart adaptations in triathletes

MRI was able to reveal changes to the heart and vessels of athletes who trained for triathalons, according to a study conducted at the University of Erlangen-Nuremburg in Germany.

In a study comparing 26 professional male triathletes and 27 male controls, cardiac MRI revealed the triathletes had larger left atria and larger right and left ventricles. The triathletes' ventricles also had greater muscle mass and wall thickness, the study found (Radiol doi:10.1148/radiol.10092377).

In competitive athletes, it's important to distinguish physiological adaptations as a result of training from pathological conditions such as cardiomyopathy, which is the most common cause of sudden cardiac death. Cardiomyopathy is present when the size of the heart's four chambers and the thickness of the heart wall become asymmetrical, so the heart is unable to pump effectively.

The triathletes had a balanced increase in left and right ventricular muscle mass, wall thickness, dilation, and diastolic function.