I21.29 – ST elevation (STEMI) myocardial infarction involving other sites

ICD-10-CM 2027 diagnosis code · Ischemic heart diseases

Billable code

ICD-10-CM code I21.29
Code
I21.29 (claims format: I2129)
Description
ST elevation (STEMI) myocardial infarction involving other sites
Short description
STEMI involving oth sites
Billable
Yes – valid for HIPAA-covered transactions
Valid for
Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter
9. Diseases of the circulatory system (I00-I99)
Block
I20-I25 Ischemic heart diseases
Parent codes
I21 › I21.2

Notes for I21.29

Applicable to:
  • Acute transmural myocardial infarction of other sites
  • Apical-lateral transmural (Q wave) infarction (acute)
  • Basal-lateral transmural (Q wave) infarction (acute)
  • High lateral transmural (Q wave) infarction (acute)
  • Lateral (wall) NOS transmural (Q wave) infarction (acute)
  • Posterior (true) transmural (Q wave) infarction (acute)
  • Posterobasal transmural (Q wave) infarction (acute)
  • Posterolateral transmural (Q wave) infarction (acute)
  • Posteroseptal transmural (Q wave) infarction (acute)
  • Septal transmural (Q wave) infarction (acute) NOS

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

I21 – Acute myocardial infarction

Includes:
  • 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
Excludes2 (not included here):
  • old myocardial infarction (I25.2)
  • postmyocardial infarction syndrome (I24.1)
  • subsequent type 1 myocardial infarction (I22.-)
Use additional code:
  • 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)

I21.2 – ST elevation (STEMI) myocardial infarction of other sites

Applicable to:
  • Type 1 ST elevation myocardial infarction of other sites

Block I20-I25

Code also:
  • the presence of hypertension (I10-I1A)

Index terms for I21.29

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in I21.2

Frequently asked questions

What is ICD-10 code I21.29?

I21.29 is the ICD-10-CM code for sT elevation (STEMI) myocardial infarction involving other sites, in the block I20-I25 (Ischemic heart diseases).

Is I21.29 a billable code?

Yes. I21.29 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does I21.29 belong to?

It belongs to category I21 – Acute myocardial infarction.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.