Table 1. Baseline patient characteristics.
| Parameters | All (n = 577) | Weekend group (n = 168) | Weekday group (n = 409) | P value |
|---|---|---|---|---|
| Age (yr) | 63.7 ± 12.8 | 63.3 ± 13.1 | 64.0 ± 12.6 | 0.586 |
| Sex (male) | 412 (71.4%) | 123 (73.2%) | 289 (70.7%) | 0.537 |
| Height (cm) | 163.5 ± 8.8 | 164.3 ± 8.8 | 163.1 ± 8.8 | 0.128 |
| Body weight (kg) | 65.2 ± 11.6 | 66.3 ± 11.3 | 64.7 ± 11.7 | 0.130 |
| Body mass index (kg/m2) | 24.3 ± 3.3 | 24.5 ± 3.1 | 24.2 ± 3.4 | 0.382 |
| Hypertension | 358 (62.0%) | 107 (63.7%) | 251 (61.4%) | 0.602 |
| Diabetes mellitus | 186 (32.2%) | 53 (31.5%) | 133 (32.5%) | 0.821 |
| Hyperlipidemia | 171 (29.6%) | 55 (32.7%) | 116 (28.4%) | 0.296 |
| Smoking, current | 193 (33.4%) | 65 (38.7%) | 128 (31.3%) | 0.087 |
| Previous myocardial infarction | 82 (14.2%) | 24 (14.3%) | 58 (14.2%) | 0.974 |
| Previous CABG | 16 (2.8%) | 6 (3.6%) | 10 (2.4%) | 0.454 |
| Hemoglobin (g/dL) | 13.9 ± 2.1 | 13.9 ± 2.0 | 13.8 ± 2.2 | 0.688 |
| eGFR (mL/min/m2) | 66.0 ± 30.4 | 67.7 ± 32.5 | 65.3 ± 29.5 | 0.382 |
| Total cholesterol (mg/dL) | 190.7 ± 45.6 | 190.1 ± 41.9 | 190.9 ± 47.1 | 0.848 |
| Triglyceride (mg/dL) | 119.8 ± 85.6 | 124.2 ± 91.7 | 118.1 ± 83.0 | 0.440 |
| HDL-cholesterol (mg/dL) | 44.0 ± 10.7 | 43.9 ± 11.5 | 44.0 ± 10.4 | 0.929 |
| LDL-cholesterol (mg/dL) | 99.0 ± 33.8 | 98.4 ± 34.1 | 99.7 ± 33.7 | 0.687 |
| NT-proBNP (pg/mL) | 2,285.6 ± 6,431.9 | 2,117.9 ± 5,678.5 | 2,356.3 ± 6,730.2 | 0.695 |
| hsCRP (mg/dL) | 1.07 ± 2.54 | 1.29 ± 3.13 | 0.99 ± 2.24 | 0.255 |
| CK-MB elevation* | 208 (36.0%) | 73 (43.5%) | 135 (33.0%) | 0.018 |
| Troponin-I elevation* | 350 (60.7%) | 119 (70.8%) | 231 (56.5%) | 0.001 |
| Ischemic ECG change | 0.143 | |||
| ST depression | 169 (29.3%) | 59 (35.1%) | 110 (26.9%) | |
| T-wave inversion | 141 (24.4%) | 38 (22.6%) | 103 (25.2%) | |
| Echocardiographic LV EF (%) | 55.9 ± 11.1 | 55.2 ± 11.0 | 56.2 ± 11.2 | 0.362 |
| TIMI risk score | 0.136 | |||
| Low (0-2) | 231 (40.0%) | 57 (33.9%) | 174 (42.5%) | |
| Intermediate (3-4) | 277 (48.0%) | 87 (51.9) | 190 (46.5%) | |
| High (5-7) | 69 (12.0%) | 24 (14.3%) | 45 (11.0%) | |
| Culprit artery | 0.864 | |||
| Left main coronary artery | 19 (3.3%) | 5 (3.0%) | 14 (3.4%) | |
| Left anterior descending artery | 290 (50.3%) | 84 (49.4%) | 206 (50.6%) | |
| Left circumflex artery | 137 (23.7%) | 43 (25.6%) | 94 (23.0%) | |
| Right coronary artery | 129 (22.4%) | 37 (22.0%) | 92 (22.5%) | |
| CAD extent | 0.726 | |||
| 1 vessel disease | 198 (34.3%) | 60 (35.1%) | 138 (34.0%) | |
| 2 vessel disease | 182 (31.6%) | 49 (29.2%) | 133 (32.5%) | |
| 3 vessel disease | 197 (34.1%) | 60 (35.7%) | 137 (33.5%) | |
| Symptom-to-admission time (hr, median) | 133.2 ± 348.0 (10.0) | 82.7 ± 260.5 (6.0) | 154.0 ± 378.0 (12.0) | 0.010 |
| Admission to-PCI time (hr, median) | 38.1 ± 50.9 (25.0) | 45.3 ± 44.9 (37.6) | 35.2 ± 53.0 (21.7) | 0.030 |
| Concomitant medication | ||||
| Heparin | 531 (92.0%) | 163 (97.0%) | 368 (90.0%) | 0.005 |
| UFH | 471 (81.6%) | 149 (88.7%) | 322 (78.7%) | 0.070 |
| Enoxaparin | 60 (10.4%) | 14 (8.3%) | 46 (11.2%) | 0.070 |
| GpIIb/IIIa R antagonists | 117 (20.3%) | 38 (22.6%) | 79 (19.3%) | 0.370 |
| Tirofiban | 19 (3.3%) | 3 (1.8%) | 16 (3.9%) | 0.303 |
| Abciximab | 100 (17.3%) | 35 (20.8%) | 65 (15.9%) | 0.154 |
| Aspirin | 577 (100.0%) | 168 (100.0%) | 409 (100.0%) | 1.000 |
| Clopidogrel | 577 (100.0%) | 168 (100.0%) | 409 (100.0%) | 1.000 |
| Beta-blocker | 372 (64.5%) | 111 (66.1%) | 261 (63.8%) | 0.633 |
| ACEI | 341 (59.2%) | 107 (63.7%) | 234 (57.4%) | 0.163 |
| ARB | 93 (16.1%) | 27 (16.1%) | 66 (16.1%) | 1.000 |
| DHP CCB | 79 (13.7%) | 24 (14.3%) | 55 (13.4%) | 0.791 |
| Non-DHP CCB | 36 (6.2%) | 12 (7.1%) | 24 (5.9%) | 0.573 |
| Nitrates | 97 (16.8%) | 26 (15.5%) | 71 (17.4%) | 0.626 |
| Statin | 474 (82.3%) | 140 (83.3%) | 334 (81.9%) | 0.720 |
*>1×upper reference limit; CABG, coronary artery bypass grafting; eGFR, estimated glomerular filtration rate; HDL, high-density lipoprotein; LDL, low-density lipoprotein; NT-proBNP, N-terminal-proB-type natriuretic peptide; hsCRP, high-sensitivity C-reactive protein; CK-MB, creatine kinase-myocardial band; ECG, electrocardiography; LV EF, left ventricular ejection fraction; TIMI, thrombolysis in myocardial infarction; CAD, coronary artery disease; PCI, percutaneous coronary intervention; UFH, unfractionated heparin; GpIIb/IIIa R, glycoprotein IIb/IIIa receptor; ACEI, angiotensin-converting-enzyme inhibitor; ARB, angiotensin receptor blocker; DHP CCB, dihydropyridine-calcium channel blocker.