I21.1
Non-billableST elevation (STEMI) myocardial infarction of inferior wall
ST elevation (STEMI) myocardial infarction of inferior wall
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Inclusion Terms
Alternative clinical terms for this condition
- Type 1 ST elevation myocardial infarction of inferior wall
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 (2)
Related Codes(7)
I21.0ST elevation (STEMI) myocardial infarction of anterior 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(2)
Frequently Asked Questions
What is the ICD-10 code for st elevation (stemi) myocardial infarction of inferior wall?
The ICD-10-CM code for st elevation (stemi) myocardial infarction of inferior wall is I21.1. The full clinical description is "ST elevation (STEMI) myocardial infarction of inferior wall". I21.1 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code I21.1 mean?
ICD-10-CM code I21.1 represents “ST elevation (STEMI) myocardial infarction of inferior wall”. 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 I21.1 a billable code?
No, I21.1 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 2 child codes under I21.1.
What chapter is I21.1 in?
I21.1 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).
What are the subcategories under I21.1?
I21.1 has 2 child codes, including: I21.11 (STEMI involving right coronary artery), I21.19 (STEMI involving oth coronary artery of inferior wall).
Are additional codes required with I21.1?
Yes, when using I21.1, 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 I21.1?
I21.1 is linked to 2 UMLS Concept Unique Identifiers: C2882099, C4509197. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does I21.1 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like st elevation (stemi) myocardial infarction of inferior wall 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 I21.1?
I21.1 maps to the ICD-11 code: BA41.Z (Acute myocardial infarction, unspecified).
Automate ICD-10 Coding With AI
Send clinical text to the AutoICD API and get back structured ICD-10 codes with confidence scores. Integrates into any EHR or billing system in minutes.
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.