I21.0 – ST elevation (STEMI) myocardial infarction of anterior wall
ICD-10-CM 2027 diagnosis code · Ischemic heart diseases
ICD-10-CM code
I21.0
- Code
I21.0(claims format:I210)- Description
- ST elevation (STEMI) myocardial infarction of anterior wall
- Billable
- No – use a more specific code below
- 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
Billable codes under I21.0
I21.0 is a header code and cannot be used on claims. Choose the most specific code:
- I21.01 – ST elevation (STEMI) myocardial infarction involving left main coronary arteryBillable
- I21.02 – ST elevation (STEMI) myocardial infarction involving left anterior descending coronary arteryBillable
- I21.09 – ST elevation (STEMI) myocardial infarction involving other coronary artery of anterior wallBillable
Notes for I21.0
Applicable to:
- Type 1 ST elevation myocardial infarction of anterior wall
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):
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)
Block I20-I25
Related codes in I21
- I21.1 – ST elevation (STEMI) myocardial infarction of inferior wallHeader
- I21.2 – ST elevation (STEMI) myocardial infarction of other sitesHeader
- I21.3 – ST elevation (STEMI) myocardial infarction of unspecified siteBillable
- I21.4 – Non-ST elevation (NSTEMI) myocardial infarctionBillable
- I21.9 – Acute myocardial infarction, unspecifiedBillable
- I21.A – Other type of myocardial infarctionHeader
- I21.B – Myocardial infarction with coronary microvascular dysfunctionBillable
Frequently asked questions
What is ICD-10 code I21.0?
I21.0 is the ICD-10-CM code for sT elevation (STEMI) myocardial infarction of anterior wall, in the block I20-I25 (Ischemic heart diseases).
Is I21.0 a billable code?
No. I21.0 is a header code with more specific child codes; report one of the billable codes listed above.
What category does I21.0 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.