Table 2.
Characteristics of patients stratified by intended use of cardiopulmonary bypass pump
| Characteristic | Baseline | Propensity Weighted | |||
|---|---|---|---|---|---|
| On-Pump (n=584,348) | Off-Pump (n=158,561) | Standardized Difference (%)a | Standardized Difference (%)a | P Value | |
| Age (yr), median (IQR) | 65 (58, 73) | 66 (58, 74) | 6.5 | 0.1 | 0.83 |
| Female (%) | 26.2 | 29.4 | 7.1 | 0.01 | 0.99 |
| BSA, median (IQR) | 2.0 (1.8, 2.2) | 2.0 (1.8, 2.1) | 8.8 | 0.02 | 0.95 |
| Hypertension | 82.7 | 82.6 | 0.2 | 0.2 | 0.44 |
| Diabetes | 38.6 | 36.2 | 4.9 | 0.2 | 0.45 |
| Chronic lung disease | 21.7 | 21.9 | 0.5 | 0.09 | |
| eGFR | |||||
| ≥90 | 24.3 | 23.2 | 2.6 | 0.03 | 0.93 |
| 60–89 | 51.6 | 51.1 | 1.1 | 0.1 | 0.85 |
| 30–59 | 22.8 | 23.9 | 2.7 | 0.02 | 0.95 |
| 15–29 | 1.3 | 1.8 | 4.0 | 0.1 | 0.78 |
| Prior cardiovascular surgery | 4.9 | 3.9 | 3.9 | 0.4 | 0.23 |
| Prior MI | 43.9 | 41.6 | 0.6 | 0.1 | 0.80 |
| CHF | 12.8 | 13.1 | 0.7 | 0.1 | 0.62 |
| Ejection fraction, median (IQR) | 55 (45, 60) | 55 (45, 60) | 6.8 | 0.7 | 0.02 |
| Left main >50% | 30.8 | 28.3 | 5.4 | 0.1 | 0.81 |
| CAD, no. of vessels | |||||
| 1 | 2.4 | 10.6 | 33.6 | 0.01 | 0.97 |
| 2 | 18.0 | 25.0 | 17.1 | 0.2 | 0.38 |
| 3 | 79.4 | 64.0 | 34.6 | 0.2 | 0.42 |
| Procedure status | |||||
| elective | 47.9 | 51.5 | 7.2 | 0.4 | 0.24 |
| urgent | 52.1 | 48.6 | 7.2 | 0.4 | 0.24 |
IQR, interquartile range; BSA, body surface area; MI, myocardial infarction; CHF, congestive heart failure; CAD, coronary artery disease.
a
Calculated as difference in group means divided by an estimate of the pooled SD; rounded to the first significant digit after the decimal point.