I21.3
BillableST elevation (STEMI) myocardial infarction of unsp site
ST elevation (STEMI) myocardial infarction of unspecified site
Coding Notes
Inclusion Terms
Alternative clinical terms for this condition
- Acute transmural myocardial infarction of unspecified site
- Transmural (Q wave) myocardial infarction NOS
- Type 1 ST elevation myocardial infarction of unspecified site
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
Related Codes(7)
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
I21.4Non-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(54)
SNOMED CT
- Acute atrial infarction194809007
- Acute myocardial infarction of atrium194809007
- Acute widespread myocardial infarction233835003
- Acute Q wave infarction - widespread233836002
- Acute Q wave myocardial infarction304914007
- Acute Q-wave infarct304914007
- Acute ST segment elevation myocardial infarction401303003
- STEMI - ST elevation myocardial infarction401303003
- Acute ST segment elevation myocardial infarction of anterior wall703164000
- Acute STEMI (ST elevation myocardial infarction) of anterior wall703164000
- Acute anterior ST segment elevation myocardial infarction703164000
- Acute myocardial infarction of right ventricle836293000
- Acute right ventricular myocardial infarction836293000
- Isolated right ventricular myocardial infarction836293000
- Acute apical myocardial infarction of heart836294006
- Acute myocardial infarction of apex of heart836294006
- Acute ST segment elevation myocardial infarction of apex of heart896696001
- Acute STEMI (ST segment elevation myocardial infarction) of apex of heart896696001
- Acute apical ST segment elevation myocardial infarction896696001
- Acute ST segment elevation myocardial infarction of right ventricle896697005
- Acute STEMI (ST segment elevation myocardial infarction) of right ventricle896697005
- Acute isolated right ventricular ST segment elevation myocardial infarction896697005
- Acute ST segment elevation myocardial infarction of atrium15713001000119100
UMLS
- Acute transmural myocardial infarction of unspecified siteC0348591
- ST elevation (STEMI) myocardial infarction of unsp siteC2882120
- ST elevation (STEMI) myocardial infarction of unspecified siteC2882120
- Transmural (Q wave) myocardial infarction NOSC2882119
- Type 1 ST elevation myocardial infarction of unspecified siteC4509199
Clinical Terms
- Acute apical ST segment elevation myocardial infarction
- Type 1 ST elevation myocardial infarction of unspecified site
- Acute apical myocardial infarction of heart
- Acute atrial infarction
- Isolated right ventricular myocardial infarction
- Acute widespread myocardial infarction
- Acute STEMI (ST segment elevation myocardial infarction) of right ventricle
- Acute ST segment elevation myocardial infarction of right ventricle
- Acute STEMI (ST elevation myocardial infarction) of anterior wall
- Acute myocardial infarction of atrium
- Acute ST segment elevation myocardial infarction of apex of heart
- Acute myocardial infarction of apex of heart
- Acute ST segment elevation myocardial infarction
- Acute transmural myocardial infarction of unspecified site
- Acute myocardial infarction of right ventricle
- STEMI - ST elevation myocardial infarction
- Acute right ventricular myocardial infarction
- Transmural (Q wave) myocardial infarction NOS
- Acute Q wave myocardial infarction
- Acute isolated right ventricular ST segment elevation myocardial infarction
- Acute Q wave infarction - widespread
- Acute STEMI (ST segment elevation myocardial infarction) of apex of heart
- Acute anterior ST segment elevation myocardial infarction
- Acute ST segment elevation myocardial infarction of anterior wall
- Acute ST segment elevation myocardial infarction of atrium
- Acute Q-wave infarct
Frequently Asked Questions
What is the ICD-10 code for st elevation (stemi) myocardial infarction of unsp site?
The ICD-10-CM code for st elevation (stemi) myocardial infarction of unsp site is I21.3. The full clinical description is "ST elevation (STEMI) myocardial infarction of unspecified site". I21.3 is a billable/specific code that can be used on insurance claims and medical billing.
What does ICD-10 code I21.3 mean?
ICD-10-CM code I21.3 represents “ST elevation (STEMI) myocardial infarction of unspecified site”. It is classified under Chapter 9: Diseases of the Circulatory System and is a billable/specific code that can be used on a claim.
Is I21.3 a billable code?
Yes, I21.3 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.
What chapter is I21.3 in?
I21.3 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).
Are additional codes required with I21.3?
Yes, when using I21.3, 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 SNOMED CT codes does I21.3 map to?
I21.3 maps to 11 SNOMED CT concepts: 233836002, 304914007, 401303003, 703164000, 896696001, and 6 more. SNOMED CT is a clinical terminology used in electronic health records.
What are the UMLS CUIs for I21.3?
I21.3 is linked to 4 UMLS Concept Unique Identifiers: C0348591, C2882120, C2882119, C4509199. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does I21.3 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like st elevation (stemi) myocardial infarction of unsp site 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 I21.3?
I21.3 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.