ICD-10-CM · Chapter 9 · I00–I99

I21

Acute myocardial infarction

Diseases of the circulatory system

Heads up:this is a parent code. It's typically not directly billable — you need to drill down to a more specific child code (one with additional digits) to use on a claim.

Quick facts

Code: I21
Type: Category / header (non-billable)
ICD-10-CM chapter: Chapter 9 — Diseases of the circulatory system
Category: I21
Specificity: 3 characters

How coders use this code

ICD-10-CM I21 is a category (header) for acute myocardial infarction. It is generally not reported directly on a claim — coders drill down to a more specific child code (one with additional characters) that matches the documentation. Use the related codes below to find the billable code that fits, and verify against the annual NCHS/CMS guidelines.

Related codes in I21

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