NPPB and atrial fibrillation: Other than the diagnostic value of NT-proBNP levels, many studies suggested higher NT-proBNP levels being associated with impaired prognosis among patients with HF [12,17,20,32,33] and atrial fibrillation [34,35]; whereas, heterogeneous findings concerning their prognostic impact in septic and cardiogenic shock was demonstrated [36,37,38].