Excludes1 pair
Q27- vs Q27.8
Q27 and Q27.8 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 Q27.8
arteriovenous malformation (Q27.3-)
Q27
Other congenital malformations of peripheral vascular system
Not billable
- Chapter 17
- Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders
- Section
- Q20-Q28
Q27.8
Other specified congenital malformations of peripheral vascular system
BillableUnspecified
- Chapter 17
- Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders
- Section
- Q20-Q28
Use when the record says
- Absence of peripheral vascular system
- Atresia of peripheral vascular system
- Congenital aneurysm (peripheral)
- Congenital stricture, artery
- Congenital varix
Indexed under
- Aberrant › artery (peripheral)
- Aberrant › subclavian artery
- Aberrant › vein NEC (peripheral)
- Absence › artery (congenital) (peripheral)
- Absence › vein congenital NEC (peripheral)
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