I am a cardiac PCU nurse and I see STEMI’s and NSTEMI’s all the time. An NSTEMI is NSTEMI (Non-ST-Elevation Myocardial Infarction) is a type of heart attack where a coronary artery is partially blocked, reducing blood flow and damaging heart muscle, but without the significant ST-segment elevation seen in a STEMI on an EKG. Diagnosed by …