TEMPORAL CHANGES IN MYOCARDIAL UPTAKE ON SERIAL BONE SCANS IN 2 CASES OF PRESUMED SENILE CARDIAC AMYLOIDOSIS

Two unusual examples of cardiac uptake in elderly patients who had received serial bone scans, one with a ''waxing'' and the other with a ''waning'' pattern of myocardial tracer uptake, are presented. An apparent temporal discordance between echocardiographic and scintigraphic findings is noted. Neither of the two patients had clinical, electrocardiographic, or other laboratory evidence of old or new myocardial infarction. Possible causes for the temporal changes are described. Presumptive diagnoses of senile cardiac amyloidosis were made based on clinical findings, noninvasive imaging, and comparison with a historic cohort at the Veterans Administration Medical Center in Houston.