Table 1. Baseline Characteristics of the Patients.
| Characteristic | No. (%) | |
|---|---|---|
| Immediate angiography group (n = 264) | Delayed angiography group (n = 258) | |
| Age, mean (SD), y | 65.8 (12.5) | 65.0 (12.2) |
| Sex | ||
| Men | 215 (81.4) | 198 (76.7) |
| Women | 49 (18.6) | 60 (23.3) |
| Hypertension | 128/260 (49.2) | 124/258 (48.1) |
| Previous event | ||
| Myocardial infarction | 70 (26.5) | 74 (28.7) |
| CABG | 41/263 (15.6) | 24/258 (9.3) |
| PCI | 44/263 (16.7) | 59/257 (23.0) |
| Coronary artery disease | 94 (35.6) | 94 (36.4) |
| Cerebrovascular accident | 19/263 (7.2) | 15/258 (5.8) |
| Diabetes | 54/263 (20.5) | 42/258 (16.3) |
| Current smoker | 47/240 (19.6) | 64/242 (26.4) |
| Hypercholesterolemia | 69/261 (26.4) | 76/256 (29.7) |
| Peripheral artery disease | 16/263 (6.1) | 22/258 (8.5) |
| Arrest witnessed | 210 (79.5) | 198 (76.7) |
| Time from arrest to, median (IQR), min | ||
| Basic life support | 2 (1 to 5) | 2 (1 to 5) |
| Return of spontaneous circulation | 15 (8 to 20) | 15 (8 to 20) |
| Signs of ischemia on ECGa | 162/253 (64.0) | 167/241 (69.3) |
| GCS score at admission, median (IQR)b | 3 (3 to 3) | 3 (3 to 3) |
| APACHE IV score, mean (SD)c | 107 (28) | 105 (32) |
| Baseline laboratory values | ||
| pH, mean (SD) | 7.2 (0.1) | 7.2 (0.1) |
| Lactic acid, median (IQR), mEq/L | 5.2 (3.0-8.8) | 4.9 (2.8-8.1) |
| Bicarbonate, mean (SD), mEq/L | 19.4 (4.4) | 19.0 (4.5) |
| Base excess | −7.5 (6.3) | −7.8 (6.2) |
| Partial pressure of oxygen, median (IQR), kPa | 14.7 (9.0-27.2) | 15.4 (10.2-28.8) |
| Creatinine, median (IQR), mg/dL | 1.15 (1.02-1.34) | 1.14 (0.98-1.29) |
| Creatine kinase, median (IQR), U/L | 164 (118-252) | 167 (118-253) |
| Creatine kinase MB, median (IQR), ng/L | 6.1 (4.0-13.8) | 6.3 (3.7-19.9) |
| Troponin T, median (IQR), ng/mL | 0.044 (0.029-0.082) | 0.053 (0.026- 0.117) |
Abbreviations: APACHE, Acute Physiology and Chronic Health Evaluation; CABG, coronary artery bypass graft; ECG, electrocardiography; GCS, Glasgow Coma Scale; IQR, interquartile range; PCI, percutaneous coronary intervention.
SI conversion factors: To convert bicarbonate to millimoles per liter, multiply by 1; creatine kinase to microkatals per liter, multiply by 0.0167; creatine kinase MB fraction to micrograms per liter, multiply by 1; creatinine to micromoles per liter, multiply by 88.4; lactic acid to millimoles per liter, multiply by 1; and troponin T to micrograms per liter, multiply by 1.
Signs of ischemia on ECG are defined as depressions of 1 mm or more in 2 contiguous leads, T-wave inversion in 2 contiguous leads, or both.
GCS scores range from 3 to 15, with lower scores indicating a reduced level of consciousness.
APACHE IV scores range from 0 to 286, with higher scores indicating a higher risk of death.