Regional variation in technetium pyrophosphate (PYP) uptake in transthyretin cardiac amyloidosis (ATTR-CA) and concomitant myocardial infarction: A case series.

- Diffuse and patchy myocardial uptake of Tc-99m PYP is well established in cases of ATTR-CA. - Chronic myocardial infarction leads to regional myocardial thinning and lack of vascular supply can present as regional sparing 'cold spot' on Tc-99m PYP imaging. - The absence of Tc-99m PYP uptake in vascular regions should raise the possibility of underlying scar.