Skip to content
Dx

ICD-10-CM 2027

ICD-10 code for ostium

Choose a code from the options below based on the documentation.

From the official ICD-10-CM alphabetic index entry “Ostium”. Page updated September 29, 2026.

About coding ostium

The official ICD-10-CM index doesn't give a single default code for ostium; the code depends on the details below.

More specific ostium codes (official index)

  • atrioventriculare commune Q21.23 — Complete atrioventricular septal defect
  • primum (arteriosum) (defect) (persistent) Q21.20 — Atrioventricular septal defect, unspecified as to partial or complete
  • secundum (arteriosum) (defect) (patent) (persistent) Q21.11 — Secundum atrial septal defect

Common questions about ostium ICD-10 codes

What is the ICD-10 code for atrioventriculare commune ostium?

Q21.23 — Complete atrioventricular septal defect.

What is the ICD-10 code for primum ostium?

Q21.20 — Atrioventricular septal defect, unspecified as to partial or complete.

What is the ICD-10 code for secundum ostium?

Q21.11 — Secundum atrial septal defect.