I21.A1: Myocardial infarction type 2

Clinical notes

Code first

This code represents a manifestation of an underlying disease. Coding convention requires the underlying (etiology) code to be sequenced first, with this code listed second.

, if applicable, the underlying cause, such as:
anemia (D50.0-D64.9)
chronic obstructive pulmonary disease (J44.-)
paroxysmal tachycardia (I47.0-I47.9)
shock (R57.0-R57.9)

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 due to demand ischemia
Myocardial infarction secondary to ischemic imbalance

Documentation support

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

•This code represents a manifestation. Documentation should identify the underlying condition, which must be coded first.
•As a general rule, code to the highest level of specificity supported by the documentation in the medical record.

Related codes in this category

I21.A9Other myocardial infarction type
I21.A1Myocardial infarction type 2

ICD-9-CM equivalent

Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.

41090Approximate match
41091Approximate match
41092Approximate match

View full ICD-10 → ICD-9 crosswalk →

Associated MS-DRGs

I21.A1 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.