2021 ICD-10-CM Code I21.A1
Myocardial infarction type 2
Valid for Submission
I21.A1 is a billable diagnosis code used to specify a medical diagnosis of myocardial infarction type 2. The code I21.A1 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.
The ICD-10-CM code I21.A1 might also be used to specify conditions or terms like myocardial infarction due to demand ischemia.
ICD-10: | I21.A1 |
Short Description: | Myocardial infarction type 2 |
Long Description: | Myocardial infarction type 2 |
Code Classification
Tabular List of Diseases and Injuries
The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code I21.A1:
Inclusion Terms
Inclusion TermsThese terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
- Myocardial infarction due to demand ischemia
- Myocardial infarction secondary to ischemic imbalance
Code First
Code FirstCertain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
Index to Diseases and Injuries
The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code I21.A1 are found in the index:
- - Infarct, infarction
- - myocardium, myocardial (acute) (with stated duration of 4 weeks or less) - I21.9
- - due to
- - demand ischemia - I21.A1
- - ischemic imbalance - I21.A1
- - secondary to
- - demand ischemia - I21.A1
- - ischemic imbalance - I21.A1
- - subsequent (recurrent) (reinfarction) - I22.9
- - type 2 - I21.A1
- - type 2 - I21.A1
- - due to
- - myocardium, myocardial (acute) (with stated duration of 4 weeks or less) - I21.9
- - Ischemia, ischemic - I99.8
- - demand (coronary) - See Also: Angina; - I24.8
- - with myocardial infarction - I21.A1
- - resulting in myocardial infarction - I21.A1
- - demand (coronary) - See Also: Angina; - I24.8
Approximate Synonyms
The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:
- Myocardial infarction due to demand ischemia
Diagnostic Related Groups - MS-DRG Mapping
The ICD-10 code I21.A1 is grouped in the following groups for version MS-DRG V38.0 What are Diagnostic Related Groups?
The Diagnostic Related Groups (DRGs) are a patient classification scheme which provides a means of relating the type of patients a hospital treats. The DRGs divides all possible principal diagnoses into mutually exclusive principal diagnosis areas referred to as Major Diagnostic Categories (MDC). applicable from 10/01/2020 through 09/30/2021.
Replacement Code
I21A1 replaces the following previously assigned ICD-10 code(s):
- I21.3 - ST elevation (STEMI) myocardial infarction of unsp site
Convert I21.A1 to ICD-9 Code
The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code I21.A1 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.
Code History
- FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
- FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
- FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
- FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018