ICD-10-CM 2027
ICD-10 code for rheumatic endocarditis
From the official ICD-10-CM alphabetic index entry “Endocarditis (chronic) (marantic) (nonbacterial) (thrombotic) (valvular) › rheumatic (chronic) (inactive) (with chorea)”. Page updated September 29, 2026.
About coding rheumatic endocarditis
The ICD-10-CM code for rheumatic endocarditis is I09.1 (Rheumatic diseases of endocardium, valve unspecified). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on I09.1.
Within I09, choose I09.1 (Rheumatic diseases of endocardium, valve unspecified) only when documentation doesn't support a more specific option: rheumatic myocarditis (I09.0), chronic rheumatic pericarditis (I09.2), other specified rheumatic heart diseases (I09.8) and rheumatic heart disease, unspecified (I09.9).
Don't report I09.1 together with the conditions in its Excludes1 note: endocarditis, valve unspecified (I38).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
More specific rheumatic endocarditis codes (official index)
Don't confuse with (Excludes1 for I09.1)
- endocarditis, valve unspecified (I38)
Common questions about rheumatic endocarditis ICD-10 codes
What is the ICD-10 code for rheumatic endocarditis?
- I09.1 — Rheumatic diseases of endocardium, valve unspecified. More specific codes apply when the documentation supports them: I01.1, I02.0.
What is the ICD-10 code for active or acute rheumatic endocarditis?
- I01.1 — Acute rheumatic endocarditis.
Is I09.1 billable?
- Yes. I09.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I09.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I09.1 as a principal diagnosis.
Is I09.1 a CC or MCC?
- No. I09.1 is neither a CC nor an MCC under MS-DRG v44.0.