Table 1.
Pre-operative and operative patient characteristics
| Variable | Development set (n = 673) | Validation set (n = 673) | P value |
|---|---|---|---|
| Age, years | 65.4 ± 10.7 | 70.6 ± 10.6 | <0.001 |
| Male | 385 (57.2) | 404 (60.0) | 0.319 |
| STS score | 1.9 ± 1.6 | 2.2 ± 1.7 | 0.004 |
| Logistic EuroSCORE | 5.0 ± 5.1 | 8.1 ± 7.3 | <0.001 |
| Additive EuroSCORE | 5.5 ± 2.4 | 6.5 ± 2.6 | <0.001 |
| NYHA class | 2.5 ± 0.9 | 2.7 ± 0.7 | 0.001 |
| Missing | 4 (0.6) | 547 (81.3) | |
| Predominant aortic stenosis | 562 (83.5) | 593 (88.1) | 0.019 |
| Predominant aortic regurgitation | 111 (16.5) | 80 (11.9) | 0.019 |
| Previous intervention | |||
| CABG | 26 (3.9) | 39 (5.8) | 0.126 |
| PCI | 16 (2.4) | 60 (8.9) | <0.001 |
| Balloon aortic valvuloplasty | 3 (0.4) | 2 (0.3) | 1.000 |
| Valve surgerya | 9 (1.3) | 7 (1.0) | 0.802 |
| Cardiac surgerya | 37 (5.5) | 47 (7.0) | 0.311 |
| Previous ischaemic stroke | 27 (4.0) | 28 (4.2) | 0.892 |
| Recent myocardial infarctiona | 12 (1.8) | 6 (0.9) | 0.235 |
| Old myocardial infarctiona | 83 (12.3) | 63 (9.4) | 0.096 |
| Hypertensiona | 333 (49.5) | 267 (39.7) | <0.001 |
| Missing | − | 402 (59.7) | |
| Chronic lung diseasea | 79 (11.7) | 97 (14.4) | 0.169 |
| Carotid diseasea | 63 (9.4) | 109 (16.2) | <0.001 |
| Peripheral arterial diseasea | 47 (7.0) | 66 (9.8) | 0.076 |
| Insulin-dependent diabetes | 18 (2.7) | 38 (5.6) | 0.009 |
| Non-insulin-dependent diabetes | 49 (7.3) | 94 (14.0) | <0.001 |
| Paroxysmal atrial fibrillation | 66 (9.8) | 57 (8.5) | 0.449 |
| Persistent/permanent atrial fibrillation | 38 (5.6) | 51 (7.6) | 0.188 |
| Serum creatinine (μmol/l) | 97.2 ± 44.2b | 88.4 ± 35.4c | <0.001 |
| Dialysis | 3 (0.4) | 7 (1.0) | 0.342 |
| Immunosuppressive therapya | 16 (2.4) | 23 (3.4) | 0.330 |
| Body mass index | 26 ± 3 | 27 ± 4 | <0.001 |
| <20 | 9 (1.3) | 6 (0.9) | 0.605 |
| 20–30 | 586 (87.1) | 520 (77.3) | <0.001 |
| ≥30 | 78 (11.6) | 147 (21.8) | <0.001 |
| Active endocarditis | 4 (0.6) | 12 (1.8) | 0.075 |
| Unstable angina | 36 (5.3) | 8 (1.2) | <0.001 |
| Left main disease | 13 (1.9) | 12 (1.8) | 1.000 |
| Aortic valve area (cm2)d | 0.73 ± 0.28 | 0.80 ± 0.22 | <0.001 |
| Missing | 327 (48.6) | 109 (16.2) | |
| Left ventricular ejection fractiond | |||
| ≥50% | 566 (84.1) | 519 (77.1) | 0.001 |
| 30–50% | 78 (11.6) | 109 (16.2) | 0.018 |
| <30% | 29 (4.3) | 45 (6.7) | 0.072 |
| Severe pulmonary hypertensiona | 24 (3.6) | 32 (4.8) | 0.339 |
| Missing | 102 (15.2) | − | |
| Urgent/emergency operationa | 28 (4.2) | 20 (3.0) | 0.244 |
| Concomitant CABG | 194 (28.8) | 300 (44.6) | <0.001 |
Values are presented as mean ± standard deviation or n (%)
CABG coronary artery bypass grafting, PCI percutaneous coronary intervention, NYHA New York Heart Association, STS Society of Thoracic Surgeons
aSee text for explanation
b1.1 ± 0.5 mg/dl
c1.0 ± 0.4 mg/dl
dOn echocardiography