ICD-10-CM 2027 diagnosis code
Q26Congenital malformations of great veins
Q26 is a header code, so it can't be reported by itself. Choose one of the 9 more specific codes beneath it.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About Q26
Q26 is the ICD-10-CM diagnosis code for congenital malformations of great veins. It belongs to block Q20-Q28 (congenital malformations of the circulatory system) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is a header code, so it can't be reported by itself; one of its 9 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: Q26.0 (cava), Q26.1 (cava), Q26.2 (connection), Q26.3 (connection), Q26.4 (unspecified), Q26.5 (connection), Q26.6 (fistula), Q26.8 (veins) and 1 more.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Specific codes under Q26
- Q26.0Congenital stenosis of vena cavaBillable
- Q26.1Persistent left superior vena cavaBillable
- Q26.2Total anomalous pulmonary venous connectionBillable
- Q26.3Partial anomalous pulmonary venous connectionBillable
- Q26.4Anomalous pulmonary venous connection, unspecifiedBillable
- Q26.5Anomalous portal venous connectionBillable
- Q26.6Portal vein-hepatic artery fistulaBillable
- Q26.8Other congenital malformations of great veinsBillable
- Q26.9Congenital malformation of great vein, unspecifiedBillable
Notes that apply from higher levels
Instructions written at a parent level also apply to Q26.
Broader instructions also apply from Chapter 17: Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about Q26
Is Q26 billable?
- No. Q26 is a header code. Report one of its more specific subcodes instead.