We report on an 80-yr-old patient with a history of inferior myocardial infarction. The patient was injected with 15 mCi of 99mTc-sestamibi when an electrocardiogram revealed new asymptomatic inferolateral ST-segment depressions. A second 99mTc study was performed 72 hr after the initial injection and after ST-segment changes had resolved. Scintigraphic acquisitions using SPECT revealed a large reduction in photon activity in the inferolateral and inferoposterior walls with 70%-80% normalization. Therefore, 99mTc-sestamibi imaging is useful in assessing asymptomatic silent myocardial ischemia.