NPPB and atrial fibrillation: Compared with patients with resting cardiac power/mass ≥ 0.7 W/m2, those with resting cardiac power/mass < 0.7 W/m2 were older, had higher NT-proBNP, more comorbidities and larger percentage of NYHA class IV, ischemic heart disease and atrial fibrillation, used more cardiovascular medications, while had lower eGFR.