Excludes1 pair
I23.4 vs I51.1
I23.4 and I51.1 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 I23.4
rupture of chordae tendineae not specified as current complication following acute myocardial infarction (I51.1)
I23.4
Rupture of chordae tendineae as current complication following acute myocardial infarction
Billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I20-I25
Indexed under
- Laceration › chordae tendinae NEC › following acute myocardial infarction (current complication)
- Rupture, ruptured › chordae tendineae NEC › following acute myocardial infarction (current complication)
- Complication › following › acute myocardial infarction NEC › chordae tendinae rupture
- Complication › following › acute myocardial infarction NEC › rupture › chordae tendineae
I51.1
Rupture of chordae tendineae, not elsewhere classified
BillableUnspecified
- Chapter 9
- Diseases of the circulatory system
- Section
- I30-I5A
Indexed under
- Laceration › chordae tendinae NEC
- Rupture, ruptured › chordae tendineae NEC
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