ICDcodes.org
FY2027

I72.0 vs Q28

I72.0 and Q28 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 Q28
ruptured malformation of precerebral vessels (I72.0)
I72.0

Aneurysm of carotid artery

Billable
Chapter 9
Diseases of the circulatory system
Section
I70-I79
Use when the record says
  • Aneurysm of common carotid artery
  • Aneurysm of external carotid artery
  • Aneurysm of internal carotid artery, extracranial portion
Indexed under
  • Aneurysm › carotid artery (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (saccular)
  • Aneurysm › neck (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (saccular)
  • Aneurysm › carotid artery › internal › extracranial portion (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (saccular)
Q28

Other congenital malformations of circulatory system

Not billable
Chapter 17
Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders
Section
Q20-Q28

These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.

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