I40
Acute myocarditis
Non-billable headerNot valid on its own. Use one of the more specific codes under it.
I40 is a non-billable ICD-10-CM code category for acute myocarditis. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are I40.0 Infective myocarditis; I40.1 Isolated myocarditis; I40.8 Other acute myocarditis and I40.9 Acute myocarditis, unspecified. Its coding notes include 1 Excludes1 entry and 10 Excludes2 entries.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
This code
- acute rheumatic myocarditis (I01.2)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (10 notes)
Inherited from Chapter 9 Diseases of the circulatory system
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- transient cerebral ischemic attacks and related syndromes (G45.-)
Includes
Further defines or gives examples of the content of the category.
This code
- subacute myocarditis