I21.B

Billable code

Myocardial infarction with coronary microvascular dysfunction

The ICD-10 code for myocardial infarction with coronary microvascular dysfunction is I21.B.

Clinical notes

Also known as

Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.

Myocardial infarction with coronary microvascular disease
Myocardial infarction with nonobstructive coronary arteries [MINOCA] with microvascular disease

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

•As a general rule, code to the highest level of specificity supported by the documentation in the medical record.

Related codes in this category

Associated MS-DRGs

I21.B can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.

Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.