Two different staging systems have been proposed: in 2016, Grogan et al. [50] demonstrated that in a cohort of wtATTR-CA patients, NT-proBNP (cutoff 3000 pg/mL) and hsTnT (cutoff 0.05 ng/mL) plasma values were able to stratify the risk for death similarly as previously observed in AL patients. The gene discussed is NPPB; the disease is axial length measurement.