Is Q21 a billable code?
No. Q21 is a header code that groups 17 more specific codes. Use one of the billable codes listed on this page instead.
ICD-10-CM FY2027 diagnosis code
Q21: Congenital malformations of cardiac septa
Header code: not billableValid for dates of service October 1, 2026 to September 30, 2027
Q21 groups related diagnoses under congenital malformations of cardiac septa. It cannot be used on a claim by itself. Choose the billable code below that matches the patient's record.
Billable codes under Q21
- Q21.0Ventricular septal defect
- Q21.10Atrial septal defect, unspecified
- Q21.11Secundum atrial septal defect
- Q21.12Patent foramen ovale
- Q21.13Coronary sinus atrial septal defect
- Q21.14Superior sinus venosus atrial septal defect
- Q21.15Inferior sinus venosus atrial septal defect
- Q21.16Sinus venosus atrial septal defect, unspecified
- Q21.19Other specified atrial septal defect
- Q21.20Atrioventricular septal defect, unspecified as to partial or complete
- Q21.21Partial atrioventricular septal defect
- Q21.22Transitional atrioventricular septal defect
- Q21.23Complete atrioventricular septal defect
- Q21.3Tetralogy of Fallot
- Q21.4Aortopulmonary septal defect
- Q21.8Other congenital malformations of cardiac septa
- Q21.9Congenital malformation of cardiac septum, unspecified
Q21 questions
What does Q21 mean?
Q21 is the ICD-10-CM code for Congenital malformations of cardiac septa. It is in chapter 17, Congenital malformations, deformations and chromosomal abnormalities (Q00-Q99).
Code titles come from the official ICD-10-CM files published by the CDC National Center for Health Statistics. Always check payer rules and the clinical record before billing.