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  6. 2024 ICD-10-CM Code I21.B

2024 ICD-10-CM Diagnosis Code I21.B

Myocardial infarction with coronary microvascular dysfunction

ICD-10-CM Code:
I21.B
ICD-10 Code for:
Myocardial infarction with coronary microvascular dysfnct
Is Billable?
Yes - Valid for Submission
Code Navigator:

Code Classification

  • Diseases of the circulatory system
    (I00–I99)
    • Ischemic heart diseases
      (I20-I25)
      • Acute myocardial infarction
        (I21)

I21.B is a billable diagnosis code used to specify a medical diagnosis of myocardial infarction with coronary microvascular dysfunction. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

Clinical Information

  • Acute Myocardial Infarction

    necrosis of the myocardium, as a result of interruption of the blood supply to the area. it is characterized by a severe and rapid onset of symptoms that may include chest pain, often radiating to the left arm and left side of the neck, dyspnea, sweating, and palpitations.

  • Acute Myocardial Infarction by ECG Finding|ACUTE MYOCARDIAL INFARCTION|Acute Myocardial Infarction|Acute Myocardial Infarction by EKG Finding

    an electrocardiographic finding showing a current of injury with st elevation. no specification is provided for localization. (cdisc)

  • Acute Myocardial Infarction From PCI Complication Type|PCI Acute Angiographic Complication|PCI Acute Angiographic Complication|PCI Acute Angiographic Complication|PCIAAC|PCIAAC

    a description of the complications from a percutaneous coronary intervention procedure that lead to an acute myocardial ischemic event.

  • Acute Myocardial Infarction Type|ACMITYPE|ACMITYPE

    a classification or description of the acute myocardial infarction.

  • Death due to Acute Myocardial Infarction Related to COVID-19|Death due to acute MI

    death by any cardiovascular mechanism (e.g., arrhythmia, sudden death, heart failure (hf), stroke, pulmonary embolus, peripheral arterial disease) less than or equal to 30 days after a myocardial infarction (mi), related to the immediate consequences of the mi, such as progressive hf or recalcitrant arrhythmia in a patient with probable or confirmed acute covid-19.

New 2024 ICD-10-CM Code

I21.B is new to ICD-10-CM code set for the FY 2024, effective October 1, 2023. The National Center for Health Statistics (NCHS) has published an update to the ICD-10-CM diagnosis codes which became effective October 1, 2023. This is a new and revised code for the FY 2024 (October 1, 2023 - September 30, 2024).

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Inclusion Terms

Inclusion Terms
These 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 with coronary microvascular disease
  • Myocardial infarction with nonobstructive coronary arteries MINOCA with microvascular disease

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Replacement Code

I21B replaces the following previously assigned ICD-10-CM code(s):

  • I21.A9 - Other myocardial infarction type

Code History

  • FY 2024 - Code Added, effective from 10/1/2023 through 9/30/2024