Table 2. Baseline characteristics before and after propensity-score matching.
|
Before matching |
p-value |
After matching |
p-value | |||
|---|---|---|---|---|---|---|
| IABP (n = 191) | Control (n = 225) | IABP (n = 129) | Control (n = 129) | |||
| Age (years) | 0.05 | 0.27 | ||||
| Mean ± SD | 57.7 ± 9.0 | 59.4 ± 9.5 | 59.1 ± 9.0 | 58.4 ± 9.3 | ||
| Median (IQR) | 58 (52–64) | 59 (53–66) | 60 (54–65) | 59 (51–66) | ||
| Female | 20 (10.5%) | 34 (15.1%) | 0.16 | 14 (10.9%) | 12 (9.3%) | 0.83 |
| BMI (kg/m2) | 0.06 | 0.84 | ||||
| Mean ± SD | 25.1 ± 3.0 | 24.6 ± 3.3 | 25.0 ± 3.0 | 24.9 ± 3.3 | ||
| Median (IQR) | 24.8 (23–27) | 24.5 (22.5–26.4) | 24.8 (22.8–27) | 24.8 (22.7–26.9) | ||
| LV diastolic dimension (mm) | 63.3 ± 5.7 | 64.1 ± 5.9 | 0.12 | 63.4 ± 3.6 | 63.5 ± 3.4 | 0.83 |
| LVEF (%) | 0.26 | 0.94 | ||||
| Mean ± SD | 32.1 ± 3.1 | 32.3 ± 3.2 | 31.9 ± 3.2 | 31.8 ± 3.5 | ||
| Median (IQR) | 33 (30–35) | 34 (31–35) | 32 (30–35) | 33 (30–34) | ||
| NYHA class | ||||||
| II | 85 (44.5%) | 81 (36%) | 0.08 | 46 (35.7%) | 48 (37.2%) | 0.80 |
| III | 95 (49.7%) | 131 (58.2%) | 0.08 | 75 (58.1%) | 74 (57.4%) | 0.91 |
| IV | 11 (5.8%) | 14 (6.2%) | 0.84 | 8 (6.2%) | 7 (5.4%) | 1.00 |
| Vessels diseased | ||||||
| Left main coronary artery | 20 (10.5%) | 20 (8.9%) | 0.59 | 13 (10.1%) | 13 (10.1%) | 1.00 |
| Left anterior descending | 185 (96.9%) | 220 (97.8%) | 0.56 | 126 (97.7%) | 127 (98.5%) | 1.00 |
| Left circumflex artery | 156 (81.7%) | 167 (74.2%) | 0.07 | 100 (77.5%) | 98 (76%) | 0.77 |
| Right coronary artery | 171 (89.5%) | 196 (87.1%) | 0.45 | 114 (88.4%) | 113 (87.6%) | 1.00 |
| Triple-vessel disease | 117 (61.3%) | 121 (53.8%) | 0.12 | 71 (55%) | 68 (52.7%) | 0.71 |
| Unstable angina | 140 (73.3%) | 171 (76%) | 0.53 | 97 (75.2%) | 97 (75.2%) | 1.00 |
| Hypertension | 86 (45%) | 95 (42.2%) | 0.57 | 55 (42.6%) | 51 (39.5%) | 0.61 |
| Hypercholesterolemia | 29 (15.2%) | 20 (8.9%) | 0.05 | 15 (11.6%) | 16 (12.4%) | 1.00 |
| Diabetes mellitus | 75 (39.3%) | 71 (31.6%) | 0.10 | 42 (32.6%) | 38 (29.5%) | 0.56 |
| History of PCI | 16 (8.4%) | 32 (14.2%) | 0.06 | 14 (10.9%) | 16 (12.4%) | 0.85 |
| Chronic obstructive pulmonary disease | 7 (3.7%) | 10 (4.4%) | 0.69 | 4 (3.1%) | 4 (3.1%) | 1.00 |
| Peripheral vascular disease | 11 (5.7%) | 7 (3.1%) | 0.19 | 4 (3.1%) | 5 (3.9%) | 1.00 |
| Cerebrovascular disease | 14 (7.3%) | 22 (9.8%) | 0.38 | 14 (10.9%) | 10 (7.8%) | 0.52 |
| Recent (14 d) myocardial infarction | 71 (37.2%) | 55 (24.4%) | 0.005 | 37 (28.7%) | 41 (31.8%) | 0.56 |
| Mitral regurgitation | 26 (13.6%) | 23 (10.2%) | 0.29 | 14 (10.9%) | 16 (12.4%) | 0.86 |
| Previous myocardial infarction | 133 (69.6%) | 140 (62.2%) | 0.11 | 87 (67.4%) | 94 (72.9%) | 0.33 |
| Ventricular aneurysm | 51 (26.7%) | 100 (44.4%) | <0.001 | 42 (32.6%) | 43 (33.3%) | 0.90 |
| Congestive heart failure | 19 (10%) | 15 (6.7%) | 0.22 | 11 (8.5%) | 10 (7.8%) | 1.00 |
| Preoperative renal insufficiency | 38 (19.9%) | 28 (12.4%) | 0.04 | 23 (17.8%) | 20 (15.5%) | 0.73 |
| Logistic EuroSCORE | 0.91 | 0.96 | ||||
| Mean ± SD | 6.8 ± 2.2 | 6.7 ± 2.1 | 6.8 ± 2.4 | 6.8 ± 2.3 | ||
| Median (IQR) | 7 (5–8) | 7 (5–8) | 7 (5–8) | 7 (5–8) | ||
| Preoperative creatinine (μmol/L) | 0.11 | 0.76 | ||||
| Mean ± SD | 86.7 ± 22.6 | 83.3 ± 21.3 | 85.4 ± 18.7 | 84.2 ± 20.4 | ||
| Median (IQR) | 80 (71.7–101) | 79 (70.8–90) | 80 (71.7–99) | 79 (71.5–92) | ||
| Preoperative lactate (mmol/L) | 0.75 | 0.60 | ||||
| Mean ± SD | 1.6 ± 0.7 | 1.6 ± 0.7 | 1.6 ± 0.7 | 1.6 ± 0.9 | ||
| Median (IQR) | 1.5 (1.2–1.8) | 1.5 (1.2–1.8) | 1.5 (1.3–1.8) | 1.5 (1.2–1.9) | ||
| Preoperative CK-MB (mmol/L) | 0.09 | 0.63 | ||||
| Mean ± SD | 7 ± 25.5 | 3.1 ± 11.5 | 3.3 ± 11.1 | 4.3 ± 15 | ||
| Median (IQR) | 1.5 (0.8–2.5) | 1.3 (0.7–2) | 1.4 (0.8–2.0) | 1.4 (0.7–2.2) | ||
| Preoperative cTNI (mmol/L) | 0.10 | 0.53 | ||||
| Mean ± SD | 3.1 ± 13.6 | 0.8 ± 3.9 | 0.7 ± 1.9 | 1.1 ± 5.0 | ||
| Median (IQR) | 0.05 (0.03–0.70) | 0.05 (0.02–0.20) | 0.05 (0.03–0.18) | 0.05 (0.03–0.50) | ||
BMI: body mass index; CK-MB: creatinine kinase isoenzyme MB; cTNI: troponin I; EuroSCORE: European System for Cardiac Operative Risk Evaluation; IABP: intra-aortic balloon pump; IQR: interquartile range; LV: left ventricular; PCI: percutaneous coronary intervention; SD: standard deviation.