Atrial fibrillation beyond the arrhythmia: hypercoagulability, adipose tissue, and fibrotic remodelling.

Abstract

![Graphic][1] Atrial fibrillation is the most common sustained arrhythmia, and its treatment continues to be a challenge. Its managment has recently been reviewed extensively in the 2016 ESC Guidelines on Atrial Fibrillation.1 Current concepts focus on the atrial substrate and triggers from the pulmonary veins as its primary mechanisms. Remodelling of artrial tissue appears to provide the substrate upon which the atrial arrhythmia can develop. In their review article ‘ Magnetic resonance imaging of atrial fibrosis: redefining atrial fibrillation to a syndrome ’,2 Pim Gal and Nassir F. Marrouche from the University of Utah School of Medicine in Salt Lake City, USA remind us that delayed enhancement-magnetic resonamce imaging (DE-MRI) has recently been introduced in the diagnosis and treatment of atrial fibrillation for the assessment of atrial fibrosis, which is considered the hallmark of the arrhythmogenic substrate in atrial fibrillation. Atrial fibrosis is an independent predictor of arrhythmia recurrences. Post-ablation DE-MRI allows for the assessment of the total scar burden, the degree of complete encirclement of pulmonary veins, and the assessment of residual fibrosis, all strong predictors of arrhythmia recurrences post-ablation. Current pathophysiological perspectives for atrial fibrillation are heavily based on the adage ‘AF begets AF’. Potentially, atrial fibrosis as such is a disease process that triggers the initiation and maintenance of atrial fibrillation While anticoagulation with vitamin K antagonists and currently mostly with novel oral anticoagulants (NOACs) prevents the most important complication of atrial fibrillation,3,4 the arrhythmia itself is managed either with drugs or with catheter ablation. Indeed, catheter ablation has become an effective treatment of paroxysmal atrial fibrillation;5 however, its use in patients with persistant atrial fibrillation is less well established. In a second clinical review entitled ‘ Catheter ablation in patients with persistent atrial fibrillation ’, Paulus Kirchhof … [1]: /embed/inline-graphic-1.gif