10ICD Code Hub

I21

Header — not billable

Acute myocardial infarction

The ICD-10 code for acute myocardial infarction is I21.

I21 is a non-billable header code. It groups related conditions but cannot be used on its own for reimbursement — select one of the 8 more specific codes below.

Clinical notes

Excludes2 (not included here)

An Excludes2 note means the excluded condition is not part of this one, but a patient can have both at the same time — in that case both codes may be reported together.

  • old myocardial infarction (I25.2)
  • postmyocardial infarction syndrome (I24.1)
  • subsequent type 1 myocardial infarction (I22.-)

Includes

Terms listed here further define or give examples of the conditions grouped under this code — they describe what the code covers, not a separate diagnosis.

  • cardiac infarction
  • coronary (artery) embolism
  • coronary (artery) occlusion
  • coronary (artery) rupture
  • coronary (artery) thrombosis
  • infarction of heart, myocardium, or ventricle
  • myocardial infarction specified as acute or with a stated duration of 4 weeks (28 days) or less from onset

Use additional code

This code represents an underlying condition. When a related manifestation is also present, coding convention calls for an additional code to be listed after this one.

  • code, if applicable, to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

Child codes under I21

Related codes in this category