Atrial Fibrillation in Athletes: A Lesson in the Virtue of Moderation.

Although the cardiovascular benefits of moderate exercise are well established, there is growing epidemiological support for the notion that high-intensity endurance athletics increases the risk of atrial fibrillation (AF). There are many gaps in evidence related to epidemiology and mechanisms of AF in endurance athletes. The proposed pathophysiological mechanisms include alterations of autonomic tone, electrical remodeling, anatomical remodeling, fibrosis, and inflammation. Clinical management of the athlete with AF often includes a period of decreased frequency, intensity, and duration of exercise with assessment for improvement in AF recurrence. Based on symptoms, a strategy of rate or rhythm control should be selected; however, due to side effects and intolerance of medications, ablation may be a preferred approach. The risks and benefits of anticoagulation for stroke prevention must be carefully assessed in the athlete with AF. All patients should be encouraged to be physically active with moderation; however, men should be advised of the higher risk of AF with long-term, high-intensity endurance training.