False negative results are found in mild ATTR-CM, specific mutations in ATTR (Phe64Leu, Ser97yr), and premature/delayed acquisition, whereas false positive results occur in severe cardiac dysfunction (blood pool), valvular/annular calcification, AL amyloidosis, AApoAI and AApoAII, ApoAIV, Aβ2M amyloidosis, rib fractures, recent myocardial infarction (<4 weeks), and hydroxychloroquine cardiac toxicity [9]. This evidence concerns the gene TTR and cutaneous mastocytosis.