Non-ST elevation (NSTEMI) myocardial infarction

This code represents a type of heart attack where there is damage to the heart muscle due to a blockage in a coronary artery, but without the characteristic ST-segment elevation seen on an electrocardiogram (ECG). It indicates myocardial necrosis without persistent ST elevation, often identified by elevated cardiac biomarkers.

Apply this code when documentation clearly states "NSTEMI," "non-ST elevation myocardial infarction," or "subendocardial infarction." This diagnosis is typically confirmed by elevated troponin levels and ischemic symptoms, in the absence of new ST elevation on ECG.

• Do not use this code for unstable angina; those conditions have separate codes.
• Always sequence this code as the principal diagnosis when it is the reason for the encounter.
• Ensure documentation specifies "non-ST elevation" to differentiate from STEMI.