NPPB and atrial fibrillation: Additionally, the disproportionately greater rise in NT-proBNP compared to the troponin levels may be attributed to the high prevalence of atrial fibrillation in this patient population, indicating that the previous studies have shown that cardiac amyloid deposition often extends beyond the left ventricle, involving other cardiac structures such as the right ventricle and atria [16,17,18].