Excludes1 pair
I05.1 vs I34.0
I05.1 and I34.0 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on I05.1
mitral insufficiency not specified as rheumatic (I34.0)
I05.1
Rheumatic mitral insufficiency
Billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I05-I09
Use when the record says
- Rheumatic mitral incompetence
- Rheumatic mitral regurgitation
Indexed under
- Insufficiency, insufficient › mitral › rheumatic
I34.0
Nonrheumatic mitral (valve) insufficiency
Billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I30-I5A
Use when the record says
- Nonrheumatic mitral (valve) incompetence NOS
- Nonrheumatic mitral (valve) regurgitation NOS
Indexed under
- Insufficiency, insufficient › mitral (valve)
- Incompetency, incompetent, incompetence › annular › mitral (valve)
- Insufficiency, insufficient › mitral › specified cause, except rheumatic
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