I41 — Myocarditis in diseases classified elsewhere
Is I41 billable?
Yes — I41 is billable for FY2027. I41 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. I41 may be submitted for encounters from October 1, 2026 through September 30, 2027.
I41 at a glance
| Code | I41 |
|---|---|
| Description | Myocarditis in diseases classified elsewhere |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
What Medicare edits apply to I41?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name I41 directly.
This code describes a manifestation of an underlying disease. The underlying condition must be sequenced before it, so it can never be the principal or first-listed diagnosis.
Which MS-DRGs does I41 group to?
I41 sits in MDC 05 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 314Other Circulatory System Diagnoses with MCCmedical
- 315Other Circulatory System Diagnoses with CCmedical
- 316Other Circulatory System Diagnoses without CC/MCCmedical
As a secondary diagnosis, I41 is a major complication or comorbidity (MCC), which can move a stay into a higher-paying DRG.
How is I41 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to I41. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Myocarditis › in › epidemic louse-borne typhus (with arteriosclerosis)(chronic)(fibroid) (interstitial) (old) (progressive) (senile)
- Myocarditis › in › typhus NEC (with arteriosclerosis)(chronic)(fibroid) (interstitial) (old) (progressive) (senile)
Excludes1 — never code together
The conditions below can never be reported together with I41 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- myocarditis (in):
- Chagas' disease (chronic) (B57.2)
- acute (B57.0)
- coxsackie (virus) infection (B33.22)
- diphtheritic (A36.81)
- gonococcal (A54.83)
- influenzal (J09.X9, J10.82, J11.82)
- meningococcal (A39.52)
- mumps (B26.82)
- rheumatoid arthritis (M05.31)
- sarcoid (D86.85)
- syphilis (A52.06)
- toxoplasmosis (B58.81)
- tuberculous (A18.84)
Code first
The underlying condition below must be sequenced before I41. I41 describes a manifestation and cannot be the principal or first-listed diagnosis.
- underlying disease, such as:
- typhus (A75.0-A75.9)
Excludes2 — not included here — inherited from Chapter 9
The conditions below are not part of I41, but a patient may have both at the same time. When documentation supports it, I41 and the excluded code may both be reported.
- 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.-)
How long has I41 existed?
I41 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with I41?
ICD-10-CM declares these codes mutually exclusive with I41 — exactly one of each pair can be correct for a given encounter.