Increased atrial, ventricular, and total epicardial fat volumes in non-valvular atrial fibrillation: a CMR DIXON study

Background Atrial fibrillation (AF) is the most prevalent persistent arrhythmia in the heart. Several clinical conditions are known to predispose AF development including obesity. Impressive data suggests that local epicardial fat depots play an important role in AF development. When determining total body fat, magnetic resonance imaging (MRI) is often regarded as the gold standard. It is also a viable option for identifying and measuring epicardial fat. We aimed to evaluate the relation between epicardial fat volume measured by cardiac MRI and the presence of non-valvular atrial fibrillation. Subjects and methods The study is an observational comparative case–control study conducted on 31 patients with AF and a comparative group of 31 individuals with matched age, sex, and other risk factors who had never experienced AF. Each participant was subjected to full history taking, a detailed history of AF, and cardiac MRI. CMR Dixon sequence was used and manually processed for epicardial fat volume quantification, then atrial, ventricular and total epicardial fat volumes were compared in the 2 groups. Results There is a statistically significant difference between AF case group vs control group with higher atrial, ventricular, and total epicardial fat volume in AF case group (193.9 ± 68.0 ml, 248.2 ± 55.5 ml, 442.1 ± 94.6 ml) vs control (91.4 ± 34.0 ml, 134.5 ± 44.4 ml, 225.9 ± 69.7 ml), respectively. Conclusion Our study reveals a higher epicardial fat volume in AF patients compared to healthy controls, suggesting epicardial fat as a potential risk factor for non-valvular AF.