| Q23 | Congenital malformations of aortic and mitral valves | NON-BILLABLE CODE |
| Q23.1 | Congenital insufficiency of aortic valve | BILLABLE CODE |
| Q23.2 | Congenital mitral stenosis | BILLABLE CODE |
| Q23.3 | Congenital mitral insufficiency | BILLABLE CODE |
| Q23.4 | Hypoplastic left heart syndrome | BILLABLE CODE |
| Q23.8 | Other congenital malformations of aortic and mitral valves | NON-BILLABLE CODE |
| Q23.81 | Bicuspid aortic valve | BILLABLE CODE |
| Q23.82 | Congenital mitral valve cleft leaflet | BILLABLE CODE |
| Q23.88 | Other congenital malformations of aortic and mitral valves | BILLABLE CODE |
| Q23.9 | Congenital malformation of aortic and mitral valves, unspecified | BILLABLE CODE |
