Alphabetic Index FY2027

I38

Endocarditis, valve unspecified

FY2027Chapter 9: Diseases of the circulatory system/I30–I5A Other forms of heart disease

BillableComplete code, valid to report
Care settingsHome Health Primary · MMTA - Cardiac and CirculatoryHospital CC

I38 is a billable ICD-10-CM diagnosis code for endocarditis, valve unspecified. It is part of the FY2027 code set, effective October 1, 2026. The Alphabetic Index lists it under 8 entries. Its coding notes include 4 Excludes1 entries and 10 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

This code
  • congenital insufficiency of cardiac valve NOS (Q24.8)
  • congenital stenosis of cardiac valve NOS (Q24.8)
  • endocardial fibroelastosis (I42.4)
  • endocarditis specified as rheumatic (I09.1)

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.-)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Cardiac and Circulatory clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

Hospital CC

Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 8 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

Includes

Further defines or gives examples of the content of the category.

This code
  • endocarditis (chronic) NOS
  • valvular incompetence NOS
  • valvular insufficiency NOS
  • valvular regurgitation NOS
  • valvular stenosis NOS
  • valvulitis (chronic) NOS

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 8 entries