NPPB and subarachnoid hemorrhage: Abbreviations: AF = atrial fibrillation, ECG = electrocardiography, HRV = heart rate variability, cTn = cardiac troponin, SAH = subarachnoid hemorrhage, CK-MB = creatine kinase-MB, BNP = brain natriuretic peptide, NT-proBNP = N-terminal of the prohormone brain natriuretic peptide, ANP = atrial natriuretic peptide, mRS = modified Rankin Scale, NIHSS = the National Institutes of Health Stroke Scale.