Subsequent non-ST elevation (NSTEMI) myocardial infarction

This code signifies a patient experiencing a new NSTEMI after a previous myocardial infarction (MI) of any type. It indicates a recurrent ischemic event where the electrocardiogram (ECG) does not show ST-segment elevation, but cardiac biomarkers are elevated. This diagnosis reflects ongoing myocardial damage due to ischemia.

Use this code when documentation clearly indicates a patient has suffered a new NSTEMI following a prior MI. This typically involves elevated cardiac enzymes (e.g., troponin) and ischemic symptoms, without persistent ST elevation on ECG, in a patient with a history of MI. The physician's assessment of a "subsequent" event is crucial.

• Ensure the documentation specifies "subsequent" or "recurrent" NSTEMI. If it's the initial NSTEMI, a different code is required.
• Always sequence this code after the appropriate code for the initial MI (e.g., I21.4 for NSTEMI, or I25.2 for old MI) if the initial MI is still relevant to the current encounter.
• Distinguish carefully between a subsequent NSTEMI and post-MI angina or other complications; elevated biomarkers are key for NSTEMI.