Table 4.
Patient Characteristics
| Characteristic | LMIV Patients (n=569) | HMIV Patients (n=17 553) | P Value |
|---|---|---|---|
| Demographics | |||
| Age, y | 68±14 | 63±14 | <0.001 |
| Female sex, % | 41 | 33 | <0.001 |
| White race, % | 76 | 78 | 0.37 |
| Body-mass index, kg/m2 | 31±18 | 30±11 | 0.22 |
| Medical history | |||
| Diabetes, % | 24 | 19 | 0.002 |
| Hypertension, % | 23 | 23 | 0.95 |
| Dyslipidemia, % | 9 | 13 | 0.003 |
| Cerebrovascular disease, % | 4 | 1 | <0.001 |
| AMI in past 6 months, % | 5 | 3 | 0.013 |
| Systolic heart failure, % | 13 | 6 | <0.001 |
| Chronic kidney disease, % | 9 | 5 | <0.001 |
| Chronic lung disease, % | 10 | 6 | 0.001 |
| AMI location | |||
| Anterior, % | 15 | 21 | <0.001 |
| Inferior, % | 21 | 35 | <0.001 |
| Non-Q-wave AMI, % | 52 | 32 | <0.001 |
| Objective findings at ICU admission | |||
| Mean blood pressure, mm Hg | 85±20 | 88±17 | 0.004 |
| Heart rate, beats per minute | 84±20 | 78±16 | <0.001 |
| White blood cell count, ×1000/μL | 12±5 | 11±5 | <0.001 |
| Hemoglobin, g/dL | 12±2 | 13±2 | <0.001 |
| Creatinine, mg/dL | 1.5±1 | 1.1±1 | <0.001 |
| Glucose, mg/dL | 154±73 | 147±71 | 0.015 |
| Troponin-I, ng/mL | 20±67 | 36±69 | <0.001 |
| Troponin-T, ng/mL | 3±6 | 5±11 | 0.026 |
| Worst laboratory studies within 72 hours | |||
| Lowest hemoglobin, g/dL | 11±2 | 12±2 | <0.001 |
| Highest creatinine, mg/dL | 1.7±2 | 1.3±1 | <0.001 |
| Highest glucose, mg/dL | 198±93 | 180±93 | <0.001 |
| Peak troponin-I, ng/mL | 24±70 | 45±78 | <0.001 |
| Peak troponin-T, ng/mL | 4±7 | 5±11 | 0.031 |
| Major interventions during first 24 hours | |||
| Thrombolytic therapy, % | 18 | 21 | 0.027 |
| Percutaneous coronary intervention, % | 66 | 78 | <0.001 |
| Endotracheal intubation, % | 16 | 5 | <0.001 |
| Inotropic or pressor support, % | 9 | 4 | <0.001 |
| APACHE-IV | 52±24 | 41±19 | <0.001 |
| APS | 38±22 | 30±16 | <0.001 |
Values are expressed as percentages or mean±standard deviation. AMI indicates acute myocardial infarction; APACHE-IV, Acute Physiology and Chronic Health Evaluation, Fourth Revision; APS, Acute Physiology Score; HMIV and LMIV, high and low annual volume of acute myocardial infarction, respectively; ICU, intensive care unit.