Q23.9 — Congenital malformation of aortic and mitral valves, unspecified
Is Q23.9 billable?
Yes, but Q23.9 is an unspecified code. Q23.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, Q23.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting Q23.9 — the more specific alternatives are listed below.
Q23.9 at a glance
| Code | Q23.9 |
|---|---|
| Description | Congenital malformation of aortic and mitral valves, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does Q23.9 group to?
Q23.9 sits in MDC 05 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 306Cardiac Congenital and Valvular Disorders with MCCmedical
- 307Cardiac Congenital and Valvular Disorders without MCCmedical
How is Q23.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to Q23.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Anomaly, anomalous › aortic cusp or valve (congenital) (unspecified type)
- Anomaly, anomalous › mitral (congenital) (unspecified type)
- Malformation › aortic valve (congenital)
- Malformation › mitral valve (congenital)
Excludes2 — not included here — inherited from Chapter 17
The conditions below are not part of Q23.9, but a patient may have both at the same time. When documentation supports it, Q23.9 and the excluded code may both be reported.
- inborn errors of metabolism (E70-E88)
How long has Q23.9 existed?
Q23.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with Q23.9?
ICD-10-CM declares these codes mutually exclusive with Q23.9 — exactly one of each pair can be correct for a given encounter.