Surgical outcome
| Level 1 | Level 2 | Level 3 | Level 4 | p-value | |
| Cardiopulmonary bypass time min | 245±35 | 247±24 | 252±34 | 281±34 | 0.2 |
| Cross-clamp time min | 131±22 | 140±23 | 141±26 | 151±22 | 0.3 |
| Total circulatory arrest min | 41±10 | 47±13 | 51±12 | 57±17 | 0.03 |
| Combined cardiac procedure | 0.9 | ||||
| Coronary artery bypass graft | 1 | 2 | 1 | 0 | |
| Resection of intracardiac mass | 1 | 1 | 0 | 0 | |
| Closure venus sinosus | 0 | 1 | 0 | 0 | |
| Duration of intubation days | |||||
| Mean±sd | 3.7±3.8 | 2.6±2.5 | 4.0±4.2 | 1.7±1.2 | 0.2 |
| Median | 2 | 2 | 3 | 1 | |
| Duration of ICU stay days | |||||
| Mean±sd | 5.8±4.0 | 4.8±4.1 | 6.3±4.1 | 5.0±3.0 | 0.8 |
| Median | 5 | 3 | 5 | 5 | |
| Duration of hospital stay days | |||||
| Mean±sd | 15±7 | 14±13 | 19±12 | 15±8 | 0.4 |
| Median | 13 | 10 | 15 | 15 |
Data are presented mean±sd or n, unless otherwise stated. ICU: intensive care unit.