Is Q28 a billable ICD-10-CM code?

No. Q28 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does Q28 sit in the tabular list?

Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations of the circulatory system (Q20-Q28).

What cannot be coded together with Q28?

Q28 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

Q28

Q28 — Other congenital malformations of circulatory system

Non-billable headerICD-10-CM

Q28 is a non-billable header ICD-10-CM code for other congenital malformations of circulatory system. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

congenital aneurysm NOS (Q27.8)
congenital coronary aneurysm (Q24.5)
ruptured cerebral arteriovenous malformation (I60.8)
ruptured malformation of precerebral vessels (I72.0)

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

congenital peripheral aneurysm (Q27.8)
congenital pulmonary aneurysm (Q25.79)
congenital retinal aneurysm (Q14.1)

Other codes that can never be billed with Q28

These codes carry an Excludes1 note pointing at Q28. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading Q28 alone.

I67.1Cerebral aneurysm, nonruptured

Risk adjustment

Q28 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead Q28

6 child codes. Green means billable.

Questions about Q28

Is Q28 a billable ICD-10-CM code?: No. Q28 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does Q28 sit in the tabular list?: Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations of the circulatory system (Q20-Q28).
What cannot be coded together with Q28?: Q28 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.