Intrinsic Sinus Node/Atrioventricular Node Dysfunction Requiring Pacemaker Implantation: Role of Former Professional Sport Activity.

Former professional endurance athletes with idiopathic SN dysfunction/AV block manifested the disease earlier in the life course compared to former power/mixed athletes and non-athletes. This suggests that bradycardia/AV block caused by intense and prolonged endurance sports may not always be benign and adaptive phenomena.