I22.2

HCC Category Mapping

What This Code Means

A heart attack that occurs after a previous heart attack, where blood flow to part of the heart is blocked but not completely, resulting in damage to the heart muscle. This code is used when the patient has had a prior myocardial infarction and experiences another one.

Coding Tips

• •Verify the timing - 'subsequent' means this is a second or later MI occurring after the initial MI episode; ensure documentation clearly indicates this is not the initial event
• •Confirm the location of the current MI (anterior wall, inferior wall, etc.) as this may require an additional 5th character code to specify the anatomical site

Clinical Significance

Subsequent NSTEMI represents a recurrent non-ST elevation myocardial infarction within 4 weeks of the initial event. This indicates persistent coronary instability and high risk of adverse outcomes. Unlike STEMI recurrences, NSTEMI recurrences may be subtler in presentation but carry equally important prognostic and treatment implications.

Documentation Requirements

• ✓Documentation of a subsequent or recurrent NSTEMI
• ✓Timing within 4 weeks of the initial myocardial infarction
• ✓Re-elevation of cardiac biomarkers above the declining baseline
• ✓Electrocardiogram without persistent ST elevation
• ✓Clinical symptoms of recurrent ischemia
• ✓Both initial (I21.x) and subsequent (I22.2) codes must be assigned

Commonly Confused Codes