I01 vs I09
I01 and I09 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on I01
chronic diseases of rheumatic origin (I05-I09) unless rheumatic fever is also present or there is evidence of reactivation or activity of the rheumatic process.
I01
Rheumatic fever with heart involvement
Not billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I00-I02
Indexed under
- Fever › rheumatic › active with heart involvement (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
I09
Other rheumatic heart diseases
Not billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I05-I09
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027