NPPB and atrial fibrillation: As authors discuss, NT-proBNP serum levels above 912 pg/mL (sensitivity 55.5%, specificity 97.9%, positive predictive value (PPV) 90.9 %, negative predictive value (NPV) 83.9%) can be used to identify those patients more prone to have AF in undetermined strokes and consequently it may aid to select subjects for prolonged cardiac rhythm monitoring in order to confirm paroxysmal AF.