The authors report a case of a left-sided silicone breast implant interfering with nuclear imaging of the myocardium. Cardiac SPECT imaging of a woman documented widespread infarct in the anterolateral, inferior, and posterolateral walls, as well as mixed ischemia/infarct in the anterior wall. Subsequent cardiac MRI revealed just anterolateral and inferolateral infarct. The anterior wall was completely viable. Also apparent on the MR images was a left breast implant overlying the anterior myocardial wall. This case of a left-sided silicone breast implant interfering with nuclear imaging of the myocardium highlights the importance of understanding the potential interference from silicone breast implants.