Endurance Exercise and Atrial Fibrillation

Abstract

Atrial fibrillation (AF) is the most frequent sustained arrhythmia and a major cause of morbidity and mortality. Increasing physical activity has convincingly shown to reduce the risk of AF. However, repetitive bouts of prolonged and vigorous endurance exercise have recently emerged as a risk factor for AF in middle-aged male athletes. Thus, a growing body of literature supports a U-shaped relation between lifetime-accumulated high-intensity endurance training and AF in men. The pathophysiology underlying this relation poses a puzzling question with multiple hypothesized mechanisms, which probably in combination create the necessary substrate and trigger for AF onset. Presumably adaptive atrial changes secondary to long-standing endurance training as part of the “athlete’s heart” add special considerations as they build up a grey zone of diagnostic uncertainty with atrial changes seen in individuals with AF. Evolving functional diagnostic modalities may re-shape this diagnostic grey zone and facilitate diagnostic workup. Initiating management of AF requires documentation of an AF episode, which can be challenging in athletes as it usually occurs intermittent. New wearable devices hold promise to facilitate early documentation and follow-up, but their reliability still has to be established, especially during exercise. When counseling competitive athletes and highly active people regarding treatment options of AF, special considerations should be taken into account to reduce risk associated with AF but also sustain the numerous health benefits of regular exercise and the lifestyle of being a competitive endurance athlete.