I30.9 vs I31.3
I30.9 and I31.3 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 I31.3
acute pericardial effusion (I30.9)
I30.9
Acute pericarditis, unspecified
BillableUnspecified
- Chapter 9
- Diseases of the circulatory system
- Section
- I30-I5A
Indexed under
- Chylopericardium › acute
- Mediastinopericarditis › acute
- Pericarditis › acute (with decompensation) (with effusion)
- Pleuropericarditis › acute
- Pneumopericarditis › acute
I31.3
Pericardial effusion (noninflammatory)
Not billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I30-I5A
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