Table 1.
Baseline and operative characteristics
| Variable (% unless otherwise indicated) | BIMA | Single IMA | |
|---|---|---|---|
| n = 1,977 | n = 14,387 | pvalue | |
| Age (mean years ± SD) | 55.5 ± 8.6 | 64.3 ± 9.6 | <0.0001 |
| Female | 10.9 | 22.6 | <0.0001 |
| Body mass index (mean kg/m2 ± SD) | 27.2 ± 3.7 | 27.9 ± 4.6 | <0.0001 |
| Diabetes mellitus | 12.3 | 31.9 | <0.0001 |
| Insulin-dependent | 2.5 | 9.7 | <0.0001 |
| Renal failure | 3.4 | 7.4 | <0.0001 |
| Previous MI | 50.5 | 52.3 | 0.13 |
| Hypertension | 49.3 | 64.0 | <0.0001 |
| Active smoking | 32.2 | 22.0 | <0.0001 |
| COPD | 6.2 | 13.1 | <0.0001 |
| Peripheral vascular disease | 9.0 | 15.3 | <0.0001 |
| Previous stroke | 3.1 | 6.3 | <0.0001 |
| LVEF ≤ 35% | 3.9 | 6.7 | <0.0001 |
| CHF NYHA class III or IV | 18.0 | 26.3 | <0.0001 |
| Atrial fibrillation | 1.5 | 3.7 | <0.0001 |
| Three-vessel disease | 58.7 | 53.0 | <0.0001 |
| Parsonnet score (mean ± SD) | 1.4 ± 0.9 | 2.1 ± 2.2 | <0.0001 |
| EuroSCORE (mean ± SD) | 1.9 ± 2.7 | 3.6 ± 4.5 | <0.0001 |
| Operative Data | |||
| Urgent or emergency | 18.5 | 23.1 | <0.0001 |
| Off-pump | 2.3 | 3.2 | 0.03 |
| Aortic clamp time (mean min ± SD) | 57.6 ± 18.2 | 50.7 ± 18.3 | <0.0001 |
| CPB time (mean min ± SD) | 82.4 ± 23.8 | 76.4 ± 23.7 | <0.0001 |
| Number of distals (mean ± SD) | 3.6 ± 1.0 | 3.3 ± 1.0 | <0.0001 |
BIMA bilateral internal mammary artery, CPB Cardiopulmonary bypass, CHF congestive heart failure, COPD chronic obstructive pulmonary disease, IMA internal mammary artery, LVEF left ventricular ejection fraction, MI myocardial infarction, NYHA New York Heart Association, SD standard deviation.