Besides its role in the screening of patients with MGUS and multiple myeloma, an NT-proBNP > 332 ng/L (in the absence of renal failure and atrial fibrillation) is indicative of cardiac involvement in established AL amyloidosis when mean LV wall thickness at echocardiography is > 12 mm [13]. The gene discussed is NPPB; the disease is atrial fibrillation.