Subsequent STEMI of unsp site

This code signifies a new ST elevation myocardial infarction (STEMI) occurring after a previous myocardial infarction, where the specific location of the new STEMI is not documented. It indicates a recurrent acute coronary event characterized by ST segment elevation on an electrocardiogram.

Use this code when a patient experiences a subsequent STEMI, and the medical record does not specify the anatomical site of the infarction. Documentation must clearly state "subsequent STEMI" or "recurrent STEMI" without a specified location.

• Always sequence this code after the code for the initial myocardial infarction (I21.-) if the patient is still within the 28-day window of the initial event.
• Avoid using this code if the site of the subsequent STEMI (e.g., anterior, inferior) is documented; instead, use the more specific I22.- code.
• Ensure documentation differentiates between a subsequent STEMI and an extension of the initial STEMI, as these are coded differently.