I was placed on Bystolic and started having chest pains about a week later. Cardiologist stopped Bystolic and placed me on Metoprolol ER and performed an echo, ekg, stress test and myocardial perfusion imaging study. MPI study showed an anterior wall perfusion defect and he felt it was due to breast tissue as ekg, echo and other views on MPI were normal. Chest pains went away for about a week and now are back. I am concerned that maybe he was wrong. So my question is, can breast tissue block imaging and look like an anterior wall perfusion defect?