Patient and operative characteristics for the analysis dataset (n=107 038)
| Characteristics | Category | Frequency (percentage) |
| Patient characteristics | ||
| Age at admission (years) | 18–36 | 1 883 (1.76) |
| 36–56 | 15 149 (14.15) | |
| *Mean: 66.20 (11.31) | 56–66 | 28 502 (26.63) |
| Median: 68 | 66–76 | 39 720 (37.11) |
| IQR: 60–74 | 76–86 | 20 682 (19.32) |
| 86–96 | 1 102 (1.03) | |
| Gender | Male | 78 261 (73.12) |
| Female | 28 774 (26.88) | |
| Unknown | 3 (<0.01) | |
| EuroSCORE (probability) | 0–0.1 | 87 559 (81.80) |
| *Mean: 0.0690 (0.0896) | 0.1–0.2 | 12 515 (11.69) |
| Median: 0.0400 | 0.2–0.3 | 3693 (3.45) |
| IQR: 0.0208–0.0777 | ≥0.3 | 3271 (3.06) |
| Operative characteristics | ||
| Priority | Elective | 74 909 (69.98) |
| Urgent | 28 312 (26.45) | |
| Emergency | 3525 (3.30) | |
| Salvage | 252 (0.23) | |
| Unknown | 40 (0.04) | |
| Operation type | CABG (isolated) | 56 586 (52.87) |
| AVR (isolated) | 9719 (9.08) | |
| MVR+other | 6178 (5.77) | |
| CABG+AVR | 8594 (8.03) | |
| CABG+other procedures | 2204 (2.06) | |
| CABG+other valve | 2860 (2.67) | |
| Other procedures | 3800 (3.55) | |
| AVR+other procedures | 2511 (2.34) | |
| CABG+AVR+other procedures | 1292 (1.21) | |
| Valve alone | 5788 (5.41) | |
| Valve+other procedures | 1542 (1.44) | |
| Unknown | 5964 (5.57) |
*For continuous variables, the mean (SD), median and IQR are shown and their intervals are given under the column ‘Category’.
AVR, aortic valve replacement or repair; CABG, coronary artery bypass grafting; MVR, mitral valve replacement or repair.