I22.0

HCC Category Mapping

What This Code Means

A second heart attack occurring within 4 weeks of the first one, affecting the front wall of the heart with ST segment elevation on the EKG.

Coding Tips

• •Code I22 is used only for recurrent MI within 4 weeks of the initial event; verify the timing in the medical record
• •Ensure documentation clearly indicates this is a subsequent/recurrent MI and not the initial event

Clinical Significance

Subsequent anterior wall STEMI indicates a recurrent myocardial infarction occurring within 4 weeks of the initial event, which significantly increases mortality risk and resource utilization. A second myocardial infarction during the acute recovery phase suggests ongoing coronary instability and often necessitates more aggressive intervention. Accurate coding of subsequent events is essential for reflecting true disease severity.

Documentation Requirements

• ✓Documentation of a second or subsequent myocardial infarction
• ✓Timing confirmation that the subsequent event occurs within 4 weeks of the initial myocardial infarction
• ✓Anterior wall location documented
• ✓Electrocardiogram showing new or recurrent ST elevation in anterior leads
• ✓New cardiac biomarker elevation above the declining baseline from the initial event
• ✓Both the initial myocardial infarction code (I21.x) and subsequent code (I22.0) should be assigned

Commonly Confused Codes