I21CurrentCategory · further specificity required

Acute myocardial infarction

Code-level instructions

Use additional code

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)

I20-I25 · Inherited instructions

Code also

the presence of hypertension (I10-I1A)

Excludes 2 · 13

I21

Excludes 2

old myocardial infarction (I25.2)
postmyocardial infarction syndrome (I24.1)
subsequent type 1 myocardial infarction (I22.-)

Chapters 9 · Diseases of the circulatory system (I00-I99)

Excludes 2

certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
systemic connective tissue disorders (M30-M36)
transient cerebral ischemic attacks and related syndromes (G45.-)

More specific codes

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 unspecified 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 dysfunction

Claims & coverage

When ICD-10-CM is required

For US diagnosis claims covered by HIPAA, ICD-10-CM is required from October 1, 2015.

Use the service date for outpatient/professional claims and the discharge date for hospital inpatient claims. Earlier encounters use ICD-9-CM; each individual code must also be valid for the applicable date.

Official coding guidelines → · CMS ↗

First observed · 2015-10-01

Code history

Latest recorded change · FY2024

ChangedUnchanged

FY2024

Effective from 2023-10-01

Inherited rules changed

Acute myocardial infarction

Category — select a more specific code

CDC/NCHS · FY2024

All editions (19)

All editions	Effective from	Code history
FY2016	2015-10-01	First observed
FY2017	2016-10-01	Code-level rules changed · Inherited rules changed
FY2018	2017-10-01	Title changed · Code-level rules changed
FY2019	2018-10-01	No tabular change
FY2020	2019-10-01	No tabular change
FY2020 · April	2020-04-01	No tabular change
FY2021	2020-10-01	No tabular change
FY2021 · 01-01	2021-01-01	No tabular change
FY2022	2021-10-01	Inherited rules changed
FY2022 · 04-01	2022-04-01	No tabular change
FY2023	2022-10-01	No tabular change
FY2023 · 04-01	2023-04-01	No tabular change
FY2024	2023-10-01	Inherited rules changed
FY2024 · 04-01	2024-04-01	No tabular change
FY2025	2024-10-01	No tabular change
FY2025 · 04-01	2025-04-01	No tabular change
FY2026	2025-10-01	No tabular change
FY2026 · April	2026-04-01	No tabular change
FY2027	2026-10-01	No tabular change

Code-level instructions

Includes

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

old myocardial infarction (I25.2)
postmyocardial infarction syndrome (I24.1)
subsequent type 1 myocardial infarction (I22.-)

Use additional code

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)

Inherited instructions

Chapters 9 · Diseases of the circulatory system (I00-I99)

Excludes 2

certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
systemic connective tissue disorders (M30-M36)
transient cerebral ischemic attacks and related syndromes (G45.-)

I20-I25 · Ischemic heart diseases (I20-I25)

Code also

the presence of hypertension (I10-I1A)

More specific codes

I21.0ST elevation (STEMI) myocardial infarction of anterior wallCategory · further specificity required I21.1ST elevation (STEMI) myocardial infarction of inferior wallCategory · further specificity required I21.2ST elevation (STEMI) myocardial infarction of other sitesCategory · further specificity required I21.3ST elevation (STEMI) myocardial infarction of unspecified siteBillable / specific I21.4Non-ST elevation (NSTEMI) myocardial infarctionBillable / specific I21.9Acute myocardial infarction, unspecifiedBillable / specific I21.AOther type of myocardial infarctionCategory · further specificity required I21.BMyocardial infarction with coronary microvascular dysfunctionBillable / specific

Related codes

Official titles and instructions are preserved in their source language. Official sources ↗

I21CurrentCategory · further specificity required

Acute myocardial infarction

Code-level instructions

Use additional code

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)

I20-I25 · Inherited instructions

Code also

the presence of hypertension (I10-I1A)

Excludes 2 · 13

I21

Excludes 2

old myocardial infarction (I25.2)
postmyocardial infarction syndrome (I24.1)
subsequent type 1 myocardial infarction (I22.-)

Chapters 9 · Diseases of the circulatory system (I00-I99)

Excludes 2

certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
systemic connective tissue disorders (M30-M36)
transient cerebral ischemic attacks and related syndromes (G45.-)

More specific codes

Claims & coverage

When ICD-10-CM is required

For US diagnosis claims covered by HIPAA, ICD-10-CM is required from October 1, 2015.

Official coding guidelines → · CMS ↗

First observed · 2015-10-01

Code history

Latest recorded change · FY2024

ChangedUnchanged

FY2024

Effective from 2023-10-01

Inherited rules changed

Acute myocardial infarction

Category — select a more specific code

CDC/NCHS · FY2024

All editions (19)

All editions	Effective from	Code history
FY2016	2015-10-01	First observed
FY2017	2016-10-01	Code-level rules changed · Inherited rules changed
FY2018	2017-10-01	Title changed · Code-level rules changed
FY2019	2018-10-01	No tabular change
FY2020	2019-10-01	No tabular change
FY2020 · April	2020-04-01	No tabular change
FY2021	2020-10-01	No tabular change
FY2021 · 01-01	2021-01-01	No tabular change
FY2022	2021-10-01	Inherited rules changed
FY2022 · 04-01	2022-04-01	No tabular change
FY2023	2022-10-01	No tabular change
FY2023 · 04-01	2023-04-01	No tabular change
FY2024	2023-10-01	Inherited rules changed
FY2024 · 04-01	2024-04-01	No tabular change
FY2025	2024-10-01	No tabular change
FY2025 · 04-01	2025-04-01	No tabular change
FY2026	2025-10-01	No tabular change
FY2026 · April	2026-04-01	No tabular change
FY2027	2026-10-01	No tabular change

Code-level instructions

Includes

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

old myocardial infarction (I25.2)
postmyocardial infarction syndrome (I24.1)
subsequent type 1 myocardial infarction (I22.-)

Use additional code

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)

Inherited instructions

Chapters 9 · Diseases of the circulatory system (I00-I99)

Excludes 2

certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
systemic connective tissue disorders (M30-M36)
transient cerebral ischemic attacks and related syndromes (G45.-)

I20-I25 · Ischemic heart diseases (I20-I25)

Code also

the presence of hypertension (I10-I1A)

More specific codes

Related codes

Official titles and instructions are preserved in their source language. Official sources ↗