Left Atrial Glucose Metabolism Evaluation by 18F-FDG-PET in Persistent Atrial Fibrillation and in Sinus Rhythm

•AF affect atrial energy demands, resulting in metabolic stress. This metabolic imbalance increases glucose uptake and is associated with the development of LA remodeling which predicts AF persistence.•Under metabolic conditions which favor glucose use by cardiomyocytes, patients with persistent AF present increased LA and LAA FDG uptake, while the FDG uptake in the LV was similar.•After return to SR, under similar conditions and with similar LV FDG uptake, LA and LAA FDG uptake decreased significantly, despite improvement of LA contractile function.•This suggests either higher overall myocardial metabolism and lower myocardial efficiency or metabolic shift to glucose as substrate in AF.