Mitral Annular Calcification as a Potential False-Positive for Cardiac Amyloidosis in 99m Tc-DPD Scintigraphy Accurately Identified by SPECT/CT.

ABSTRACT: 99m Tc-PYP/DPD/HDMP cardiac scintigraphy has a pivotal role in the diagnosis of ATTR cardiac amyloidosis. The combined findings of a Perugini visual score of 2 or 3 in the scan and the absence of monoclonal proteins in blood and urine are highly specific for the diagnosis of ATTR cardiac amyloidosis without a tissue biopsy. We report a case of mitral annular and valve calcification accurately identified in the SPECT/CT, but which could be misinterpreted as ATTR cardiac amyloidosis if only acquiring planar and SPECT images.