NPPB and atrial fibrillation: In the Cox univariate regression analysis, significant predictors of AF late recurrence were AF duration, hypertension, left atrial thrombosis, New York Heart Association class, pre-operative serum BNP level, pre-operative heart rate and LAD, pre-operative left ventricular ejection fraction, redo-procedure, post-operative atrial tachyarrhythmias, AF at discharge and post-operative amiodarone.