Q23.88 Other congenital malformations of aortic and mitral valves

The ICD-10-CM code for Other congenital malformations of aortic and mitral valves is Q23.88 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

17: Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0)

Section

Q20-Q28: Congenital malformations of the circulatory system (Q20-Q28)

Category Q23

11 codes (9 billable)

FY2026 Status

Introduced in FY2025

Also Known As

ICD-10-CM Alphabetic Index entries that lead to Q23.88:

• Quadricuspid aortic valve
• Supernumerary (congenital) › aortic cusps
• Deformity › aortic › cusp or valve (congenital)
• Anomaly, anomalous (congenital) (unspecified type) › mitral (leaflets) (valve) › specified NEC
• Supernumerary (congenital) › cusps, heart valve NEC › aortic
• Malformation (congenital) › aortic valve › specified NEC
• Malformation (congenital) › mitral valve › specified NEC

Official Coding Guidelines

POA indicator for congenital conditions/anomalies and Q00-Q99 exception

Congenital conditions and anomalies Assign “Y” for congenital conditions and anomalies except for categories Q00- Q99, Congenital anomalies, which are on the exempt list. Congenital conditions are always considered present on admission.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool