Q21.3 – Tetralogy of Fallot
ICD-10-CM 2027 diagnosis code · Congenital malformations of the circulatory system
ICD-10-CM code
Q21.3
- Code
Q21.3(claims format:Q213)- Description
- Tetralogy of Fallot
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 17. Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA1)
- Block
- Q20-Q28 Congenital malformations of the circulatory system
- Parent codes
- Q21
Notes for Q21.3
Applicable to:
- Ventricular septal defect with pulmonary stenosis or atresia, dextroposition of aorta and hypertrophy of right ventricle.
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
Q21 – Congenital malformations of cardiac septa
Excludes1 (not coded here):
- acquired cardiac septal defect (I51.0)
Index terms for Q21.3
Entries in the ICD-10-CM alphabetic index that lead to this code:
- Syndrome, Fallot's
- Tetralogy of Fallot
- Fallot's, tetrad or tetralogy
- Dextraposition, aorta, in tetralogy of Fallot
- Anomaly, anomalous, heart, tetralogy of Fallot
- Stenosis, stenotic, pulmonary, in tetralogy of Fallot
- Defect, defective, ventricular septal, in tetralogy of Fallot
- Imperfect, closure, septum, ventricular, in tetralogy of Fallot
- Defect, defective, interventricular septal, in tetralogy of Fallot
- Imperfect, closure, septum, interventricular, in tetralogy of Fallot
- Hypertrophy, hypertrophic, ventricle, ventricular, in tetralogy of Fallot
- Stenosis, stenotic, pulmonary, with ventricular septal defect, transposition of aorta, and hypertrophy of right ventricle
- Defect, defective, interventricular septal, with dextroposition of aorta, pulmonary stenosis and hypertrophy of right ventricle
- Imperfect, closure, septum, ventricular, with pulmonary stenosis or atresia, dextraposition of aorta, and hypertrophy of right ventricle
- Anomaly, anomalous, heart, septum, ventricular, with pulmonary stenosis or atresia, dextraposition of aorta and hypertrophy of right ventricle
- Anomaly, anomalous, heart, septum, interventricular, with pulmonary stenosis or atresia, dextraposition of aorta and hypertrophy of right ventricle
Related codes in Q21
Frequently asked questions
What is ICD-10 code Q21.3?
Q21.3 is the ICD-10-CM code for tetralogy of Fallot, in the block Q20-Q28 (Congenital malformations of the circulatory system).
Is Q21.3 a billable code?
Yes. Q21.3 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
What category does Q21.3 belong to?
It belongs to category Q21 – Congenital malformations of cardiac septa.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.