Boraita A, et al. - In this 20-year study of 6,813 Spanish elite athletes (35.0% women), with most sports disciplines represented, researchers focused on the incidence of atrial fibrillation (AF) as well as its relation to potential risk factors. The athletes with and without reported AF were compared via cross-sectional analysis. The studied athletes were on national teams and competed in major international events. Echocardiographic assessments were performed by cardiologists who were not blinded to the condition (AF or no AF) of the athletes. The participants had mean (SD) age 22 (7) years, and mean (SD) time of competition 8 (5) years. A low AF incidence was reported among young Spanish elite athletes, even when considering only endurance athletes. A higher AF risk was reported in association with increasing values of age, years of competition, and left atrial anteroposterior diameter in multivariate analysis. There is a need to monitor potential contributors (particularly atrial remodeling).