Q26.9 — Congenital malformation of great vein, unspecified
Is Q26.9 billable?
Yes, but Q26.9 is an unspecified code. Q26.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, Q26.9 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 Q26.9 — the more specific alternatives are listed below.
More specific alternatives
- Q26.0Congenital stenosis of vena cava
- Q26.1Persistent left superior vena cava
- Q26.2Total anomalous pulmonary venous connection
- Q26.3Partial anomalous pulmonary venous connection
- Q26.5Anomalous portal venous connection
- Q26.6Portal vein-hepatic artery fistula
- Q26.8Other congenital malformations of great veins
Q26.9 at a glance
| Code | Q26.9 |
|---|---|
| Description | Congenital malformation of great vein, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does Q26.9 group to?
Q26.9 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
As a secondary diagnosis, Q26.9 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is Q26.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to Q26.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Anomaly, anomalous › vena cava (congenital) (unspecified type)
- Anomaly, anomalous › vein › great (congenital) (unspecified type)
- Deformity › vein › great
- Malformation › great › vein (congenital)
Inclusion terms
Alternative wording in documentation that is classified to Q26.9.
- Congenital anomaly of vena cava (inferior) (superior) NOS
Excludes2 — not included here — inherited from Chapter 17
The conditions below are not part of Q26.9, but a patient may have both at the same time. When documentation supports it, Q26.9 and the excluded code may both be reported.
- inborn errors of metabolism (E70-E88)
How long has Q26.9 existed?
Q26.9 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.
What other codes are in the Q26 family? (8)
- Q26.0Congenital stenosis of vena cava
- Q26.1Persistent left superior vena cava
- Q26.2Total anomalous pulmonary venous connection
- Q26.3Partial anomalous pulmonary venous connection
- Q26.4Anomalous pulmonary venous connection, unspecified
- Q26.5Anomalous portal venous connection
- Q26.6Portal vein-hepatic artery fistula
- Q26.8Other congenital malformations of great veins