Circulating BDNF in Patients With Atrial Fibrillation Undergoing Catheter Ablation or Exercise Training

The main purpose of this project is to determine the impact of atrial fibrillation interventions (catheter ablation and exercise training) on circulating BDNF concentrations in patients with atrial fibrillation. It also seeks to determine if there is a relation between circulating BDNF concentrations and mental health (depression severity, quality of life and symptoms) among those undergoing interventions for atrial fibrillation catheter ablation or exercise training. Using a pre-post study design, the investigators will explore interventions in two subsets of patients at the opposite end of the atrial fibrillation clinical spectrum. Arm 1: patients with paroxysmal atrial fibrillation will undergo catheter ablation (n=100). Arm 2: patients with permanent or persistent atrial fibrillation will perform exercise training 2 times weekly for 12 weeks (n=100). Total sample size will be 200 participants. All measurements will be performed at baseline and follow-up.