Table 1.
Demographics, operative characteristics, and clinical outcomes of patients in the test and validation cohorts
| Demographics | Test cohort (n = 545) | Validation cohort (n = 1013) |
|---|---|---|
| Gender (male) | 80% | 79% |
| Age (years) | 66 (58–74) | 70 (62–77)* |
| BMI (kg/m2) | 28 (26–32) | |
| Caucasian race (%) | 91 | 90 |
| Past medical history | ||
| LVEF preoperative (%) | 55 (50–60) | |
| Diabetes (insulin or non-insulin dependent; %) | 29 | |
| Pulmonary disease (COPD, Asthma; %) | 4.0 | |
| Creatinine (mg/dL) | 1.0 (0.9–1.2) | |
| Haematocrit (%) | 39.8 (36.9–43.0) | |
| Hypertension (treated or by history; %) | 74 | |
| Hypercholesterolemia (treated or by history; %) | 79 | |
| Previous myocardial infarction (%) | 25 | |
| Medications—pre-operative (%) | ||
| ACE-inhibitor | 46 | |
| β-Blocker | 81 | |
| Ca2+ antagonist | 13 | |
| Aspirin | 80 | |
| HMG CoA reductase inhibitor | 82 | |
| Biomarkers—pre-operative | ||
| CKMB (µg/L) | 0.5 (0.2–1.1) | |
| cTnI (µg/L) | 0 (0–0.02) | |
| cTnT (µg/L) (n = 494) | 0.04 (0.01–0.62) | |
| Surgery (no. grafts; %) | ||
| 1 | 2 | |
| 2 | 13 | |
| 3 | 47 | |
| ≥4 | 38 | |
| CPB duration (min) | 102 (76–125) | |
| Aortic cross-clamp duration (min) | 77 (59–96) | |
| Post-operative data | ||
| HLOS (days) | 7 (6–9) | 7 (6–9) |
| Mortality % (n) up to 5 years | 6.1% (33) | 8.2% (83) |
Data are shown as percentage for dichotomous variables and median [25th, 75th percentiles for inter-quartile range (IQR)] for continuous variables. BMI, body mass index; LVEF, left ventricular ejection fraction; ACE, angiotensin converting enzyme; HMG, 3-hydroxy-3-methyl-glutaryl-CoA reductase; CKMB, creatinine kinase MB fraction; cTnI or cTnT, cardiac troponin I or T; CPB, cardiopulmonary bypass; HLOS, hospital length of stay. P-values are Kruskal–Wallis one-way analysis of variance by ranks for continuous data and χ2 distribution or Fisher’s exact for nominal and ordinal data.
*P < 0.0001.