AutoICD API

I21.9

Billable

Acute myocardial infarction, unspecified

Acute myocardial infarction, unspecified

Status

Billable / Specific

Block

I20-I25

Parent Code

I21

ICD-11 Mapping

1 equivalent

Coding Notes

Inclusion Terms

Alternative clinical terms for this condition

  • Myocardial infarction (acute) NOS

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

Use Additional Code

Additional codes that should follow this code

Code Also

A second code may be required; sequencing depends on circumstances

Related Codes(7)
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

BillableI21.4

Non-ST elevation (NSTEMI) myocardial infarction

BillableI21.A

Other type of myocardial infarction

I21.B

Myocardial infarction with coronary microvascular dysfnct

Billable
ICD-11 Equivalents(1)

ICD-11 Equivalents

View full mapping

Corresponding ICD-11 codes from the WHO crosswalk mapping

BA41.ZAcute myocardial infarction, unspecifiedequivalentPrimary
Also Known As / Clinical Terms(222)

SNOMED CT

UMLS

Clinical Terms

  • Cardiac infarction
  • Rupture of ventricle due to acute myocardial infarction
  • ECG: myocardial infarction
  • Coronary embolism
  • Coronary embolus
  • Acute myocardial infarction of anterolateral wall
  • Postoperative acute myocardial infarction
  • EKG: myocardial infarction
  • Widowmaker heart attack
  • Acute anteroapical myocardial infarction
  • Pulmonary embolism following acute myocardial infarction
  • Acute myocardial infarction due to left coronary artery occlusion
  • Acute septal infarction
  • Acute myocardial infarction, unspecified site, episode of care unspecified
  • acute myocardial infarction (MI)
  • Acute myocardial infarction of inferolateral wall with posterior extension
  • True posterior wall infarction
  • Cardiac rupture after acute myocardial infarction
  • Acute myocardial infarction of right ventricle
  • Pericarditis due to acute myocardial infarction
  • Coronary artery perforation
  • Acute myocardial infarction of inferolateral wall
  • Acute inferolateral myocardial infarction
  • Heart attack
  • Acute myocardial infarction of lateral wall
  • Coronary artery embolism
  • Mixed myocardial ischaemia and infarction
  • Coronary artery rupture
  • Aneurysmal lesion of coronary artery
  • AMI
  • Electrocardiogram finding of infarction
  • Acute apical myocardial infarction of heart
  • Acute atrial infarction
  • Mitral valve regurgitation due to acute myocardial infarction with papillary muscle and chordal rupture
  • Acute myocardial infarction of high lateral wall
  • acute mi
  • Acute myocardial infarction of apex of heart
  • Acute myocardial infarction of basal inferior segment of left ventricle
  • Acute papillary muscle infarction
  • Acute inferolateral myocardial infarction with posterior extension
  • Acute myocardial infarction of anterior wall
  • Acute myocardial infarction due to occlusion of circumflex branch of left coronary artery
  • Acute anteroseptal myocardial infarction
  • Acute myocardial infarction of inferior wall involving right ventricle
  • Acute myocardial infarction following operative procedure
  • Myocardial infarction (acute) NOS
  • Acute myocardial infarction during procedure
  • Acute Q-wave infarct
  • Acute myocardial infarction of anterior wall involving right ventricle
  • Myocardial infarction due to atherothrombotic coronary artery disease
  • Acute myocardial infarction, unspecified site
  • Acute lateral myocardial infarction
  • Acute myocardial infarction of septum alone
  • MINOCA - myocardial infarction with non-obstructive coronary artery
  • Acute myocardial infarction of apical-lateral wall
  • True posterior myocardial infarction
  • Myocardial infarction with non-obstructive coronary artery
  • Acute widespread myocardial infarction
  • Acute anteroapical infarction
  • Cardiac rupture due to and following acute myocardial infarction
  • Myocardial infarction acute
  • Acute myocardial infarction with rupture of ventricle
  • Myocardial infarction in recovery phase
  • Myocardial infarct
  • Myocardial infarction
  • Acute anterior myocardial infarction
  • Acute infarction of papillary muscle
  • Acute inferior myocardial infarction
  • Coronary artery aneurysm
  • Mixed myocardial ischemia and infarction
  • Acute myocardial infarction due to right coronary artery occlusion
  • Myocardial necrosis
  • New myocardial infarction compared to prior study
  • Mitral valve regurgitation due to acute myocardial infarction
  • Infarction of heart
  • Acute right ventricular myocardial infarction
  • Acute myocardial infarction of inferior wall
  • Aneurysm of coronary vessels
  • Acute myocardial infarction of inferior wall with right ventricular involvement
  • Acute myocardial infarction of posterolateral wall
  • Coronary artery aneurysm with rupture
  • First myocardial infarction
  • Acute myocardial infarction (disorder)
  • Acute myocardial infarction of posterobasal wall
  • Electrocardiographic myocardial infarction
  • Isolated right ventricular myocardial infarction
  • Mitral valve regurgitation due to acute myocardial infarction without papillary muscle and chordal rupture
  • Acute myocardial infarction of septum
  • Coronary artery aneurysm with perforation
  • AMI - Acute myocardial infarction
  • Acute myocardial infarction of atrium
  • Pericarditis secondary to acute myocardial infarction
  • Acute myocardial infarction of diaphragmatic wall
  • Type 1 myocardial infarction
  • Acute posterior myocardial infarction
  • Acute myocardial infarction of anterior wall with right ventricular involvement
  • Rupture of coronary artery co-occurrent and due to aneurysm of coronary artery
  • Acute anterolateral myocardial infarction
  • Acute Q wave myocardial infarction
  • Acute inferoposterior infarction
  • Perforation of coronary artery co-occurrent and due to aneurysm of coronary artery
  • MI - myocardial infarction
  • Pulmonary embolism due to and following acute myocardial infarction
  • Acute periprocedural myocardial infarction
  • Pulmonary embolism as current complication following acute myocardial infarction
  • Drug-related myocardial necrosis syndrome
  • Postoperative myocardial infarction
  • Acute myocardial infarction of inferoposterior wall
Frequently Asked Questions
What is the ICD-10 code for acute myocardial infarction, unspecified?

The ICD-10-CM code for acute myocardial infarction, unspecified is I21.9. The full clinical description is "Acute myocardial infarction, unspecified". I21.9 is a billable/specific code that can be used on insurance claims and medical billing.

What does ICD-10 code I21.9 mean?

ICD-10-CM code I21.9 represents “Acute myocardial infarction, unspecified”. 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 I21.9 a billable code?

Yes, I21.9 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.

What chapter is I21.9 in?

I21.9 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).

Are additional codes required with I21.9?

Yes, when using I21.9, 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 I21.9 map to?

I21.9 maps to 54 SNOMED CT concepts: 57054005, 304914007, 54329005, 52035003, 70211005, and 49 more. SNOMED CT is a clinical terminology used in electronic health records.

What are the UMLS CUIs for I21.9?

I21.9 is linked to 1 UMLS Concept Unique Identifier: C0155626. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

How does I21.9 relate to ICF functioning codes?

ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like acute myocardial infarction, unspecified 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 I21.9?

I21.9 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.