I21
Non-billableAcute myocardial infarction
Acute myocardial infarction
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Includes
Conditions included under this code
- 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
Excludes 2
Conditions not included here, but the patient may have both
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
- •systemic connective tissue disordersM30-M36
- •transient cerebral ischemic attacks and related syndromesG45
- •old myocardial infarctionI25.2
- •postmyocardial infarction syndromeI24.1
- •subsequent type 1 myocardial infarctionI22
Use Additional Code
Additional codes that should follow this code
- code, if applicable, to identify:
- •exposure to environmental tobacco smokeZ77.22
- •history of tobacco dependenceZ87.891
- •occupational exposure to environmental tobacco smokeZ57.31
- •status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facilityZ92.82
- •tobacco dependenceF17
- •tobacco useZ72.0
Code Also
A second code may be required; sequencing depends on circumstances
Child Codes (8)
I21.0ST elevation (STEMI) myocardial infarction of anterior wall
I21.1ST elevation (STEMI) myocardial infarction of inferior wall
I21.2ST elevation (STEMI) myocardial infarction of other sites
I21.3ST elevation (STEMI) myocardial infarction of unsp site
I21.4Non-ST elevation (NSTEMI) myocardial infarction
I21.9Acute myocardial infarction, unspecified
I21.AOther type of myocardial infarction
I21.BMyocardial infarction with coronary microvascular dysfnct
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(101)
UMLS
- AMIC0027051
- Attack coronaryC0027051
- Attack heart (NOS)C0027051
- Cardiac infarctionC0027051
- Cardiovascular StrokeC0027051
- Cardiovascular StrokesC0027051
- Heart AttackC0027051
- Heart AttacksC0027051
- Heart attackC0027051
- Infarct myocardialC0027051
- Infarct, MyocardialC0027051
- Infarction of heartC0027051
- Infarction, MyocardialC0027051
- Infarctions, MyocardialC0027051
- Infarcts, MyocardialC0027051
- MI - myocardial infarctionC0027051
- Myocardial InfarctC0027051
- Myocardial InfarctionC0027051
- Myocardial InfarctionsC0027051
- Myocardial InfarctsC0027051
- Myocardial infarctC0027051
- Myocardial infarctionC0027051
- Myocardial infarction (MI)C0027051
- Myocardial infarction (disorder)C0027051
- Right ventricular infarctionC0027051
- Stroke, CardiovascularC0027051
- Strokes, CardiovascularC0027051
- attack heartsC0027051
- attacking heartC0027051
- attacks coronaryC0027051
- attacks heartsC0027051
- cardiac infarctionC0027051
- coronary attackC0027051
- disorder infarction myocardialC0027051
- heart attackC0027051
- heart attacksC0027051
- heart infarctionC0027051
- infarctions myocardialC0027051
- infarcts myocardialC0027051
- miesC0027051
- myocardial infarctionC0027051
- myocardial infarctionsC0027051
- myocardial infarctsC0027051
- myocardial necrosisC0027051
- syndrome myocardial infarctionC0027051
- AMI - Acute myocardial infarctionC0155626
- Acute Myocardial InfarctionC0155626
- Acute myocardial infarctionC0155626
- Acute myocardial infarction (disorder)C0155626
- Acute myocardial infarction, unspecifiedC0155626
- Acute myocardial infarction, unspecified siteC0155626
- Acute myocardial infarction, unspecified site, episode of care unspecifiedC0155626
- Myocardial infarction (acute) NOSC0155626
- Myocardial infarction acuteC0155626
- Widowmaker heart attackC0155626
- acute miC0155626
- acute myocardial infarctionC0155626
- acute myocardial infarction (MI)C0155626
- CT - Coronary thrombosisC0010072
- Coronary ThrombosesC0010072
- Coronary ThrombosisC0010072
- Coronary artery thrombosisC0010072
- Coronary artery thrombosis (disorder)C0010072
- Coronary thrombosisC0010072
- Occlusive coronary artery thrombusC0010072
- Thromboses, CoronaryC0010072
- Thrombosis - coronaryC0010072
- Thrombosis coronaryC0010072
- Thrombosis, CoronaryC0010072
- coronary (artery) thrombosisC0010072
- coronary artery thrombosisC0010072
- coronary thrombosisC0010072
- thrombosis coronaryC0010072
- Coronary OcclusionC0151814
- Coronary OcclusionsC0151814
- Coronary artery occludedC0151814
- Coronary artery occlusionC0151814
- Coronary occlusionC0151814
- Coronary occlusion (disorder)C0151814
- Occlusion coronaryC0151814
- Occlusion coronary arteryC0151814
- Occlusion, CoronaryC0151814
- Occlusions, CoronaryC0151814
- arteries coronary occludedC0151814
- artery coronary occlusionC0151814
- coronary (artery) occlusionC0151814
- coronary artery occludedC0151814
- coronary artery occlusionC0151814
- coronary occlusionC0151814
- occlusion coronaryC0151814
- Coronary artery embolismC0264686
- Coronary artery embolism (disorder)C0264686
- Coronary embolismC0264686
- Coronary embolusC0264686
- Embolus coronary arteryC0264686
- coronary (artery) embolismC0264686
- Coronary artery ruptureC0264688
- Coronary artery rupture (disorder)C0264688
- coronary (artery) ruptureC0264688
- infarction of heart, myocardium, or ventricleC4290137
- myocardial infarction specified as acute or with a stated duration of 4 weeks (28 days) or less from onsetC4290138
Frequently Asked Questions
What is the ICD-10 code for acute myocardial infarction?
The ICD-10-CM code for acute myocardial infarction is I21. The full clinical description is "Acute myocardial infarction". I21 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code I21 mean?
ICD-10-CM code I21 represents “Acute myocardial infarction”. It is classified under Chapter 9: Diseases of the Circulatory System and is a non-billable header code. Use a more specific child code for billing purposes.
Is I21 a billable code?
No, I21 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 8 child codes under I21.
What chapter is I21 in?
I21 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).
What are the subcategories under I21?
I21 has 8 child codes, including: I21.0 (ST elevation (STEMI) myocardial infarction of anterior wall), I21.1 (ST elevation (STEMI) myocardial infarction of inferior wall), I21.2 (ST elevation (STEMI) myocardial infarction of other sites), I21.3 (ST elevation (STEMI) myocardial infarction of unsp site), and 4 more.
Are additional codes required with I21?
Yes, when using I21, also report: 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).
What are the UMLS CUIs for I21?
I21 is linked to 8 UMLS Concept Unique Identifiers: C0027051, C0155626, C0010072, C0151814, C0264686, and 3 more. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does I21 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like acute myocardial infarction affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of I21?
I21 maps to the ICD-11 code: BA41.Z (Acute myocardial infarction, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.