Table 2. Preoperative patient characteristics before and after PS matching* (modified according to [16]).
| All patients (n = 1282) | PS-matched patients (n = 788) | |||||
|---|---|---|---|---|---|---|
| Clampless _OPCAB (n = 395) | cCABG _(n = 887) | z-difference | Clampless _OPCAB (n = 394) | cCABG _(n = 394) | z-difference | |
| Age (years) | 69.3 ± 9.1 | 67.5 ± 9.4 | 3.24 | 69.3 ± 9.1 | 69.0 ± 8.9 | 0.46 |
| Male (%) | 78.2 | 77.9 | 0.13 | 78.2 | 77.9 | 0.09 |
| BMI (kg/m²) | 27.8 ± 4.2 | 28.3 ± 4.5 | −1.83 | 27.8 ± 4.2 | 28.0 ± 4.2 | −0.60 |
| Left main artery disease (%) | 25.3 | 25.5 | −0.06 | 25.1 | 24.9 | 0.08 |
| LVEF (%) | 56.7 ± 12.3 | 55.4 ± 14.1 | 1.64 | 56.6 ± 12.2 | 56.9 ± 13.3 | −0.28 |
| Preoperative myocardial infarction (%) | 27.1 | 35.7 | −3.14 | 27.2 | 26.7 | 0.16 |
| Hypertension (%) | 82.3 | 84.1 | −0.80 | 82.2 | 82.2 | 0 |
| Diabetes mellitus (%) | 22.8 | 31.7 | −3.39 | 22.8 | 19.8 | 1.05 |
| COPD (%) | 5.8 | 7.1 | −0.88 | 5.8 | 6.1 | −0.15 |
| Renal insufficiency (%) | 0.8 | 1.2 | −0.86 | 0.8 | 0.3 | 1.16 |
| Stroke (%) | 1.0 | 2.4 | −2.03 | 1.0 | 1.8 | −0.95 |
| PAOD (%) | 11.9 | 11.4 | 0.26 | 11.7 | 14.7 | −1.27 |
| Previous cardiac surgeries (n) | 0.05 ± 0.26 | 0.08 ± 0.39 | −1.56 | 0.05 ± 0.26 | 0.06 ± 0.27 | −0.80 |
| Urgency
(%) Elective Urgent Emergency Last resort |
91.9 2.5 5.3 0.3 |
81.0 9.8 8.7 0.6 |
−4.82 |
91.9 2.5 5.3 0.3 |
92.4 2.3 4.8 0.5 |
0.25 |
| Preoperative IABP (%) | 1.0 | 1.5 | −0.71 | 1.0 | 1.0 | 0 |
*Mean ± standard deviation is given for continuous patient characteristics. Relative frequency as a percentage is given for categorical patient characteristics.
BMI. body mass index; cCABG. conventional CABG; CABG. coronary artery bypass grafting; COPD. chronic obstructive pulmonary disease; IABP. intra-aortic balloon pump; clampless OPCAB. clampless off-pump coronary artery bypass grafting; LVEF. left-ventricular ejection fraction; PAOD. peripheral arterial occlusive disease; PS. propensity score