| Q26 | Congenital malformations of great veins | NON-BILLABLE CODE |
| Q26.0 | Congenital stenosis of vena cava | BILLABLE CODE |
| Q26.1 | Persistent left superior vena cava | BILLABLE CODE |
| Q26.2 | Total anomalous pulmonary venous connection | BILLABLE CODE |
| Q26.3 | Partial anomalous pulmonary venous connection | BILLABLE CODE |
| Q26.4 | Anomalous pulmonary venous connection, unspecified | BILLABLE CODE |
| Q26.5 | Anomalous portal venous connection | BILLABLE CODE |
| Q26.6 | Portal vein-hepatic artery fistula | BILLABLE CODE |
| Q26.8 | Other congenital malformations of great veins | BILLABLE CODE |
