Operative details for the study population
| Frequency (%) | |
| Elective | 16156 (68.1) |
| Urgent | 6823 (28.7) |
| Emergency | 693 (2.9) |
| Salvage | 68 (0.3) |
| Isolated CABG | 12470 (52.5) |
| Isolated non-CABG | 4984 (21.0) |
| Two major cardiac procedures | 4766 (20.1) |
| Three major cardiac procedures | 1520 (6.4) |
| Isolated aortic valve replacement | 3116 (13.1) |
| Aortic valve replacement + CABG | 2401 (10.1) |
| Surgery on aortic valve | 7316 (30.8) |
| Surgery on mitral valve | 2944 (12.4) |
| Surgery on tricuspid valve | 691 (2.9) |
| Surgery on pulmonary valve | 108 (0.5) |
| Surgery on the thoracic aorta | 1010 (4.3) |