Baseline characteristics of the study population
| All patients (n=1920) | ≤99th centile (n=1620) | >99th centile (n=300) | P values | |
| Baseline characteristics | ||||
| Age | 61.5 (14.2) | 60.3 (14.1) | 67.7 (13.3) | <0.001 |
| Male (%) | 1174 (61.1) | 975 (60.2) | 199 (66.3) | 0.052 |
| Chest pain (%) | 1613 (84.3) | 1369 (84.8) | 244 (81.3) | 0.389 |
| Symptom to arrival time (min) | 199 (118–461.5) | 199 (115–445) | 199 (134–521) | 0.044 |
| Medical history | ||||
| Diabetes mellitus (%) | 281 (14.6) | 222 (13.7) | 59 (19.7) | 0.009 |
| Hypertension (%) | 763 (39.7) | 614 (37.9) | 149 (49.7) | <0.001 |
| Hyperlipidaemia (%) | 760 (39.6) | 630 (38.9) | 130 (43.3) | 0.167 |
| Family history (%) | 922 (48.0) | 782 (48.3) | 140 (46.7) | 0.654 |
| Ischaemic heart disease (%) | 578 (30.1) | 474 (29.3) | 104 (34.7) | 0.071 |
| Previous myocardial infarction (%) | 455 (23.7) | 361 (22.3) | 94 (31.3) | 0.001 |
| Previous percutaneous coronary intervention (%) | 363 (18.9) | 294 (18.1) | 69 (23.0) | 0.059 |
| Previous coronary artery bypass grafting (%) | 117 (6.1) | 88 (5.4) | 29 (9.7) | 0.007 |
| Previous heart failure (%) | 64 (3.3) | 46 (2.8) | 18 (6.0) | 0.009 |
| Previous stroke (%) | 119 (6.2) | 96 (5.9) | 23 (7.7) | 0.309 |
| Smoker (%) | 385 (20.1) | 327 (20.2) | 58 (19.3) | 0.581 |
| Medication on admission | ||||
| Aspirin (%) | 650 (33.9) | 530 (32.7) | 120 (40.0) | 0.017 |
| Clopidogrel (%) | 250 (13.0) | 201 (12.4) | 49 (16.3) | 0.078 |
| Beta-blocker (%) | 518 (27.0) | 427 (26.4) | 91 (30.3) | 0.176 |
| ACE Inhibitor (%) | 578 (30.1) | 469 (29.0) | 109 (36.3) | 0.013 |
| Statin (%) | 819 (42.7) | 678 (41.9) | 141 (47.0) | 0.111 |
| Calcium channel blocker (%) | 240 (12.5) | 195 (12.0) | 45 (15.0) | 0.183 |
| Warfarin (%) | 104 (5.4) | 83 (5.1) | 21 (7.0) | 0.238 |
| ECG findings | ||||
| ST depression (%) | 112 (5.8) | 62 (3.8) | 50 (16.7) | <0.001 |
| ST elevation (%) | 58 (3.0) | 40 (2.5) | 18 (6.0) | 0.002 |
| T-wave inversion (%) | 298 (15.5) | 213 (13.1) | 85 (28.3) | <0.001 |
| Adjudicated index diagnosis | ||||
| Type 1 myocardial infarction (%) | 274 (14.3) | 54 (3.3) | 220 (73.3) | <0.001 |
| Type 2 myocardial infarction (%) | 64 (3.3) | 17 (1.0) | 47 (15.7) | <0.001 |
| Myocardial injury (%) | 28 (1.5) | 2 (0.1) | 26 (8.7) | <0.001 |
| 30-Day outcomes | ||||
| Type 1 myocardial infarction at 30 days (%)* | 8 (0.4) | 2 (0.1) | 6 (2.0) | <0.001 |
| Cardiac death at 30 days (%) | 6 (0.3) | 2 (0.1) | 4 (1.3) | 0.004 |
| Type 1 myocardial infarction or cardiac death at 30 days (%) | 277 (14.4) | 57 (3.5) | 220 (73.3) | <0.001 |
Troponin strata based on presentation concentration. Values are mean (SD), median (IQR) or n(%).
↵*Excluding index events.