ICD-10 codes for Myocardial Infarction
Myocardial Infarction is coded primarily under I21, I21.3, I21.4 in the ICD-10-CM (Clinical Modification) classification. Top-level categories include I21 (Acute myocardial infarction); I22 (Subsequent STEMI & NSTEMI mocard infrc); I25 (Chronic ischemic heart disease). The 2025 ICD-10-CM code set includes 94 codes related to myocardial infarction, of which 74 are billable (specific enough to appear on a medical claim).
Myocardial infarction (heart attack) is coded under I21 (acute) and I22 (subsequent, within 28 days) in ICD-10-CM. I21.0 to I21.2 cover STEMI by anatomical site, I21.4 is NSTEMI, I21.A1 is type 2 MI, and I21.A9 is other MI types. I25.2 is used for an old (healed) MI.
Total Codes
94
Billable Codes
74
Categories
3
SNOMED CT Concepts
25+
Top 12 Relevant ICD-10 Codes
The codes most commonly assigned to myocardial infarction, ranked by primary-match status, billable status, and specificity. Tap a code to see its full ICD-10 detail page.
I21.3ST elevation (STEMI) myocardial infarction of unsp site
I21.4Non-ST elevation (NSTEMI) myocardial infarction
I25.2Old myocardial infarction
I21.A1Myocardial infarction type 2
I21Acute myocardial infarction
I22Subsequent STEMI & NSTEMI mocard infrc
I21.9Acute myocardial infarction, unspecified
I21.BMyocardial infarction with coronary microvascular dysfnct
I22.0Subsequent STEMI of anterior wall
I22.1Subsequent STEMI of inferior wall
I22.2Subsequent non-ST elevation (NSTEMI) myocardial infarction
I22.8Subsequent STEMI of sites
Primary Code Categories
These are the top-level ICD-10-CM categories for myocardial infarction. Click any code to see all specific subcodes within that group.
Billable / Specific Codes (74)
Specific ICD-10-CM codes that can be reported on medical claims for myocardial infarction.
I21.01STEMI involving left main coronary artery
I21.02STEMI involving left anterior descending coronary artery
I21.09STEMI involving oth coronary artery of anterior wall
I21.11STEMI involving right coronary artery
I21.19STEMI involving oth coronary artery of inferior wall
I21.21STEMI involving left circumflex coronary artery
I21.29STEMI involving oth sites
I21.3ST elevation (STEMI) myocardial infarction of unsp site
I21.4Non-ST elevation (NSTEMI) myocardial infarction
I21.9Acute myocardial infarction, unspecified
I21.A1Myocardial infarction type 2
I21.A9Other myocardial infarction type
I21.BMyocardial infarction with coronary microvascular dysfnct
I22.0Subsequent STEMI of anterior wall
I22.1Subsequent STEMI of inferior wall
I22.2Subsequent non-ST elevation (NSTEMI) myocardial infarction
I22.8Subsequent STEMI of sites
I22.9Subsequent STEMI of unsp site
I25.10Athscl heart disease of native coronary artery w/o ang pctrs
I25.110Athscl heart disease of native cor art w unstable ang pctrs
I25.111Athscl heart disease of native cor art w ang pctrs w spasm
I25.112Athscl heart dis of native cor art with refract ang pctrs
I25.118Athscl heart disease of native cor art w oth ang pctrs
I25.119Athscl heart disease of native cor art w unsp ang pctrs
I25.2Old myocardial infarction
I25.3Aneurysm of heart
I25.41Coronary artery aneurysm
I25.42Coronary artery dissection
I25.5Ischemic cardiomyopathy
I25.6Silent myocardial ischemia
I25.700Atherosclerosis of CABG, unsp, w unstable angina pectoris
I25.701Athscl CABG, unsp, w angina pectoris w documented spasm
I25.702Athscl CABG, unspecified, with refractory angina pectoris
I25.708Atherosclerosis of CABG, unsp, w oth angina pectoris
I25.709Atherosclerosis of CABG, unsp, w unsp angina pectoris
I25.710Athscl autologous vein CABG w unstable angina pectoris
I25.711Athscl autologous vein CABG w ang pctrs w documented spasm
I25.712Athscl autologous vein CABG with refractory angina pectoris
I25.718Athscl autologous vein CABG w oth angina pectoris
I25.719Athscl autologous vein CABG w unsp angina pectoris
I25.720Athscl autologous artery CABG w unstable angina pectoris
I25.721Athscl autologous artery CABG w ang pctrs w documented spasm
I25.722Athscl autologous artery CABG with refractory ang pctrs
I25.728Athscl autologous artery CABG w oth angina pectoris
I25.729Athscl autologous artery CABG w unsp angina pectoris
I25.730Athscl nonautologous biological CABG w unstable ang pctrs
I25.731Athscl nonaut biological CABG w ang pctrs w documented spasm
I25.732Athscl nonaut biological CABG with refractory ang pctrs
I25.738Athscl nonautologous biological CABG w oth angina pectoris
I25.739Athscl nonautologous biological CABG w unsp angina pectoris
...and 24 more specific codes. Search all codes.
Cross-Mappings to Other Standards
ICD-10-CM codes for myocardial infarction link to several adjacent terminologies. These mappings are precomputed from official sources (NLM RxNav, UMLS Metathesaurus, SNOMED CT International) and served via AutoICD's reference and translate APIs.
SNOMED CT
25+ concepts mapped from this code group. Concept IDs include 15713081000119108, 285981000119103, 840309000, 840312002, ....
Browse SNOMED CT directoryUMLS Metathesaurus
25+ CUIs indexed. Sample: C0010072, C0027051, C0151814, C0155626, ....
Browse UMLS directoryICD-11
ICD-11 (WHO 2022) classifies many of these conditions under different chapter and stem-code structures. Use the converter to see specific ICD-10 to ICD-11 mappings.
Open ICD-10 to ICD-11 converterFrequently Asked Questions
What is the ICD-10 code for myocardial infarction?
The primary ICD-10-CM codes for myocardial infarction are I21, I21.3, I21.4. Across all sub-categories, 94 codes are grouped under myocardial infarction, with 74 marked as billable (specific enough for a medical claim).
How many ICD-10 codes are there for myocardial infarction?
There are 94 ICD-10-CM codes related to myocardial infarction. Of these, 74 are billable specific codes and 20 are non-billable header categories that organize the specific codes underneath them. Header codes cannot be reported on a claim by themselves.
Is there a billable ICD-10 code for myocardial infarction?
Yes. 74 of the 94 ICD-10-CM codes for myocardial infarction are billable. Common examples include I21.01 (STEMI involving left main coronary artery); I21.02 (STEMI involving left anterior descending coronary artery); I21.09 (STEMI involving oth coronary artery of anterior wall). Code to the highest level of specificity supported by the documentation.
Which myocardial infarction ICD-10 code should I use for billing?
The most commonly used billable codes for myocardial infarction include: I21.01 (STEMI involving left main coronary artery); I21.02 (STEMI involving left anterior descending coronary artery); I21.09 (STEMI involving oth coronary artery of anterior wall). The correct code depends on the documented clinical presentation, including any complications, episode (acute / chronic), and laterality where applicable. Always code to the highest level of specificity supported by the clinical documentation.
Is I21 a billable ICD-10 code?
No, I21 (Acute myocardial infarction) is a non-billable header code. You need to use a more specific child code for billing purposes.
What are the SNOMED CT concepts for myocardial infarction?
The ICD-10 codes for myocardial infarction map to at least 25 SNOMED CT concepts. Examples of SNOMED CT concept IDs in this group include 15713081000119108, 285981000119103, 840309000, 840312002, 840316004. SNOMED CT is a clinical terminology used in electronic health records; AutoICD's coding API returns SNOMED CT IDs alongside each ICD-10 code via the include_snomed=true flag.
What UMLS Concept Unique Identifiers (CUIs) cover myocardial infarction?
The ICD-10 codes for myocardial infarction are linked to at least 25 UMLS CUIs in the National Library of Medicine's Metathesaurus. Sample CUIs include C0010072, C0027051, C0151814, C0155626, C0264686. UMLS CUIs unify the same concept across SNOMED CT, ICD-10, ICD-11, RxNorm, MeSH, and dozens of other source vocabularies.
What are other names for myocardial infarction in ICD-10?
Myocardial Infarction may also be referred to as: myocardial infarction, MI, heart attack, STEMI, NSTEMI, acute MI. The same ICD-10-CM codes apply regardless of which term appears in the clinical documentation. Synonyms are surfaced by AutoICD's NER pass and mapped to the canonical ICD-10 family above.
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