NPPB and atrial fibrillation: AF: atrial fibrillation; BMI: body mass index; CHD: coronary heart disease; NT-proBNP: N-terminal pro brain natriuretic peptide; LAD: left atrial diameter; LVEDD: left ventricular end-diastolic diameter; LVESD: left ventricular end-systolic diameter; LVEF: left ventricular ejection fraction.