I40Header code — not billable
Acute myocarditis
- Chapter
- 9. Diseases of the circulatory system
- Category
- I40
- Effective date
- October 1, 2026
Related codes in category I40
Frequently asked questions
What is ICD-10 code I40?
I40 is an ICD-10-CM diagnosis code for Acute myocarditis.
Is I40 a billable code?
No. I40 is a category/header code, not billable on its own — use one of its more specific child codes instead.
What ICD-10-CM chapter is I40 in?
I40 falls under Chapter 9: Diseases of the circulatory system.
When did I40 become effective?
I40 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to I40?
I40 belongs to category I40, which includes 4 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.