Table 2.
Patient characteristics and door-to-balloon time
| Hours | ||||||||
|---|---|---|---|---|---|---|---|---|
| Characteristic | Overall | <1 | 1–2 | 2–3 | 3–4 | 4+ | P | P trend |
| n=1932 | n=111 | n=758 | n=599 | n=224 | n=240 | - | - | |
| Demographics | ||||||||
| Median age (IQR) | 73 (69–78) | 72 (69–78) | 72 (69–78) | 73 (69–78) | 74 (70–78) | 74 (70–78) | 0.010 | - |
| Women | 44.7 | 36.9 | 42.2 | 46.7 | 49.6 | 46.7 | 0.088 | 0.020 |
| White race | 92.3 | 94.6 | 95.0 | 91.2 | 88.4 | 89.2 | 0.002 | <0.001 |
| Smoker | 20.2 | 14.4 | 21.6 | 22.5 | 15.2 | 17.1 | 0.037 | 0.22 |
| Cerebrovascular disease | 10.4 | 9 | 7.9 | 12.5 | 10.7 | 13.3 | 0.035 | 0.013 |
| Prior coronary bypass | 8.9 | 7.2 | 7 | 9.2 | 12.5 | 11.7 | 0.046 | 0.005 |
| Prior percutaneous coronary intervention | 12.2 | 20.7 | 10.3 | 13.2 | 9.8 | 14.2 | 0.013 | 0.99 |
| Hypertension | 58.6 | 50.4 | 55 | 60.9 | 58.9 | 67.5 | 0.003 | <0.001 |
| Diabetes mellitus | 22.9 | 25.2 | 18.9 | 21.9 | 26.8 | 33.8 | <0.001 | <0.001 |
| Prior myocardial infarction | 19.2 | 17.1 | 15.4 | 21.9 | 21.4 | 23.3 | 0.010 | 0.003 |
| Congestive heart failure | 6.7 | 4.5 | 5.9 | 6.7 | 6.7 | 10.4 | 0.15 | 0.019 |
| Chronic obstructive pulmonary disease | 15.9 | 12.6 | 15.6 | 16.4 | 16.1 | 17.5 | 0.83 | 0.32 |
| Presentation | ||||||||
| Symptoms <6 hours | 73.2 | 79.3 | 81.3 | 73.3 | 67.9 | 50.0 | <0.001 | <0.001 |
| No chest pain | 3.7 | 1.8 | 2.2 | 4.0 | 3.1 | 9.2 | <0.001 | <0.001 |
| Median sytolic blood pressure (IQR) | 136 (115–159) | 132 (113–150) | 135 (114–160) | 136 (113–156) | 140 (120–162) | 140 (120–160) | 0.045 | - |
| Median heart rate (IQR) | 76 (63–89) | 76 (63–89) | 75 (60–88) | 75 (62–89) | 79 (66–93) | 80 (67–92) | <0.001 | - |
| Shock | 7.1 | 9.0 | 6.1 | 7.7 | 5.8 | 9.6 | 0.30 | 0.31 |
| Cardiac arrest | 5.3 | 3.6 | 4.5 | 6.7 | 4.9 | 5.4 | 0.41 | 0.38 |
| Electrocadiographic findings | ||||||||
| Anterior myocardial infarction | 56.5 | 55.9 | 54.9 | 59.6 | 54 | 56.7 | 0.45 | 0.71 |
| Left bundle branch block on admission | 4.8 | 1.8 | 2.1 | 4.2 | 9.5 | 11.7 | <0.001 | <0.001 |
| Median sum ST elevation | 7.5 (5.0–12.0) | 9.0 (5.0–13.0) | 8.0 (5.5–13.0) | 7.0 (4.5–12.0) | 6.5 (4.0–11.0) | 6.5 (4.0–10.0) | <0.001 | - |
| Q wave myocardial infarction | 88.6 | 89.2 | 90.8 | 88.2 | 87.5 | 83.8 | 0.049 | 0.005 |
| Hospital characteristics | ||||||||
| Median myocardial infarction volume (IQR) | 202 (136–340) | 192 (148–340) | 203 (142–325) | 214 (136–346) | 188 (129–364) | 202 (132–326) | 0.81 | - |
| On-site surgical back-up | 89.2 | 91.9 | 88.3 | 89.6 | 89.7 | 89.6 | 0.78 | 0.78 |
| Ownership | 0.40 | - | ||||||
| Public | 10.3 | 9.1 | 11.2 | 8.9 | 13.1 | 8.8 | ||
| Not-for-profit | 77.8 | 76.4 | 77.9 | 79.4 | 72.1 | 79.5 | ||
| For-profit | 11.9 | 14.6 | 10.8 | 11.7 | 14.9 | 11.7 | ||
| Teaching status | 0.18 | - | ||||||
| Non-teaching | 47.1 | 52.2 | 45.1 | 46.7 | 51.3 | 47.9 | ||
| Teaching | 35.9 | 31.5 | 39.4 | 35.9 | 29.9 | 32.1 | ||
| Council of Teaching Hospitals | 17 | 16.2 | 15.4 | 17.4 | 18.8 | 20 | ||
| Rural hospital | 5.5 | 6.4 | 5.5 | 6.7 | 4.5 | 3.4 | 0.36 | 0.20 |