Although echocardiography showed mild left ventricular diastolic dysfunction without characteristic findings for cardiac amyloidosis such as a classical granular sparkling appearance, we did not exclude cardiac amyloidosis because 1) both serum NT-pro brain natriuretic peptide (BNP) (369.7 pg/mL) and troponin T levels (0.166 ng/mL) were elevated and 2) the patient had a history of atrial fibrillation. The gene discussed is NPPB; the disease is cardiac amyloidosis.