2027 ICD-10-CM Diagnosis Code I41Myocarditis in diseases classified elsewhere

ICD-10-CM Codes›I00–I99›I30-I5A›I41

ICD-10-CM I41
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I41 is a billable ICD-10-CM diagnosis code for myocarditis in diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 314 through 316, 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 22 closely related codes. The code is a manifestation code that cannot be reported as the principal diagnosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Myocarditis and cardiomyopathy.

Code Identity

ICD-10-CM Code
I41
Billable Status
Yes — Valid for Submission
Code Describes
Myocarditis in diseases classified elsewhere
Short Description
Myocarditis in diseases classified elsewhere
Same as the full description in the CMS dataset.
Chapter
I30-I5A
Other forms of heart disease

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI30-I5AOther forms of heart disease
CategoryI41Myocarditis in diseases classified elsewhere
This CodeI41Myocarditis in diseases classified elsewhere

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I41.

Manifestation diagnoses
Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and therefore should not be used as a principal diagnosis.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute myocarditis associated with another disorder
  • Chagas' disease with heart involvement
  • Chronic Chagas' disease
  • Congenital rubella syndrome
  • Heart disease co-occurrent with human immunodeficiency virus infection
  • Myocarditis co-occurrent with human immunodeficiency virus infection
  • Myocarditis due to autoimmune disease
  • Myocarditis due to Chaga disease
  • Myocarditis due to childhood type dermatomyositis
  • Myocarditis due to COVID-19
  • Myocarditis due to hypersensitivity state
  • Myocarditis due to idiopathic hypereosinophilic syndrome
  • Myocarditis due to Kawasaki disease
  • Parasitic myocarditis
  • Protozoan myocarditis
  • Rubella myocarditis
  • Subacute myocarditis with AIDS

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I41: its own notes plus those printed at Chapter 9. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 9 (I00-I99) Diseases of the circulatory system applies to 1,433 codes
  • 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.-)

Code First

The underlying condition named in the note is sequenced before this code.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR CIR005
Myocarditis and cardiomyopathy
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Cardiomyopathy

Cardiomyopathy is the name for diseases of the heart muscle. These diseases enlarge your heart muscle or make it thicker and more rigid than normal. In rare cases, scar tissue replaces the muscle tissue.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert I41 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
422.0 Ac myocardit in oth dis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About I41Overview

What is the ICD-10 code for myocarditis in diseases classified elsewhere?

The ICD-10-CM code for myocarditis in diseases classified elsewhere is I41. It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is I41 (Myocarditis in diseases classified elsewhere) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report myocarditis in diseases classified elsewhere on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I41 group to?

On inpatient claims, myocarditis in diseases classified elsewhere maps to MS-DRG 793, 791, 314, 316, 315, with relative weights from 0.6678 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is I41 a CC or MCC?

CMS lists I41 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 22 closely related codes in its exclusion list.

Can I41 be a principal diagnosis?

No. This is a manifestation code: myocarditis in diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.