Supplementary Table 2.
Baseline Characteristics of Consecutive Patients in the Emergency Department With and Without Cardiac Troponin Testing Requested by the Attending Clinician
| Troponin requested by clinician |
||||
|---|---|---|---|---|
| All (n=1,054) | No (n=918) | Yes (n=136) | P-value | |
| Male sex | 505 (47.9) | 426 (46.4) | 79 (58.1) | 0.014 |
| Age (years) | 54.5 ± 22.6 | 53.0 ± 23.0 | 64.9 ± 16.4 | <0.001 |
| Elevated cardiac troponin* | 144 (13.7) | 114 (12.4) | 30 (22.1) | <0.001 |
| Presenting complaint | ||||
| Chest pain, n (%) | 183 (17.6) | 75 (8.3) | 108 (79.4) | <0.001 |
| Abdominal pain, n (%) | 160 (15.2) | 156 (17.0) | 4 (2.9) | <0.001 |
| Fall/collapse, n (%) | 158 (15.0) | 151 (16.4) | 7 (5.1) | 0.001 |
| Dyspnea, n (%) | 57 (5.4) | 51 (5.6) | 6 (4.4) | 0.728 |
| Confusion, n (%) | 18 (1.7) | 17 (1.9) | 1 (0.7) | 0.56 |
| Dizziness, n (%) | 14 (1.3) | 13 (1.4) | 1 (0.7) | 0.806 |
| Other, n (%) | 464 (44.0) | 455 (49.6) | 9 (6.6) | <0.001 |
| Risk factors | ||||
| Smoker | 299 (33.1) | 258 (33.2) | 41 (32.5) | 0.957 |
| Ex-smoker | 154 (17.1) | 119 (15.3) | 35 (27.8) | 0.001 |
| Hypertension | 337 (32.4) | 257 (28.4) | 80 (59.3) | <0.001 |
| Hyperlipidemia | 299 (28.7) | 230 (25.4) | 69 (51.5) | <0.001 |
| Family history | 26 (2.5) | 9 (1.0) | 17 (12.7) | <0.001 |
| Past medical history | ||||
| Ischemic heart disease | 193 (18.5) | 127 (14.0) | 66 (48.9) | <0.001 |
| Myocardial infarction | 109 (10.5) | 61 (6.7) | 48 (35.6) | <0.001 |
| Cerebrovascular disease | 99 (9.5) | 83 (9.2) | 16 (11.9) | 0.403 |
| Peripheral vascular disease | 50 (4.8) | 43 (4.7) | 7 (5.2) | 0.992 |
| Diabetes mellitus | 106 (10.1) | 81 (8.9) | 25 (18.5) | 0.001 |
| Previous revascularisation | ||||
| PCI | 52 (5.0) | 28 (3.1) | 24 (17.8) | <0.001 |
| CABG | 32 (3.1) | 19 (2.1) | 13 (9.6) | <0.001 |
| Admission physiological parameters | ||||
| Respiratory rate (bpm) | 18.2 ± 4.2 | 18.3 ± 4.3 | 17.8 ± 3.4 | 0.253 |
| Temperature (oC) | 36.9 ± 0.9 | 36.9 ± 0.9 | 36.6 ± 0.6 | 0.003 |
| Pulse rate (bpm) | 86.9 ± 22.3 | 87.7 ± 22.1 | 81.8 ± 23.0 | 0.008 |
| Systolic BP (mmHg) | 130.5 ± 22.2 | 130.5 ± 22.3 | 130.8 ± 21.9 | 0.887 |
| Oxygen saturations (%) | 96.8 ± 2.9 | 96.8 ± 3.0 | 96.7 ± 2.2 | 0.7 |
| On oxygen | 62 (6.6) | 52 (6.3) | 10 (8.1) | 0.598 |
| Consciousness | 0.515 | |||
| Alert | 1014 (96.8) | 880 (96.6) | 134 (98.5) | |
| Verbal | 14 (1.3) | 14 (1.5) | 0 (0.0) | |
| Pain | 8 (0.8) | 7 (0.8) | 1 (0.7) | |
| Unresponsive | 11 (1.1) | 10 (1.1) | 1 (0.7) | |
| Killip class | 0.012 | |||
| 0 | 6 (0.6) | 6 (0.7) | 0 (0.0) | |
| 1 | 930 (89.7) | 819 (90.8) | 111 (82.2) | |
| 2 | 85 (8.2) | 65 (7.2) | 20 (14.8) | |
| 3 | 15 (1.4) | 11 (1.2) | 4 (3.0) | |
| 4 | 1 (0.1) | 1 (0.1) | 0 (0.0) | |
| Hematology and biochemistry | ||||
| Hemoglobin (g/dL) | 13.3 ± 1.9 | 13.3 ± 2.0 | 13.2 ± 1.7 | 0.590 |
| Creatinine (mg/dL) | 0.97 ± 0.72 | 0.96 ± 0.74 | 1.04 ± 0.58 | 0.207 |
| Urea (mg/dL) | 6.1 ± 3.7 | 5.9 ± 3.7 | 6.8 ± 3.8 | 0.017 |
| Troponin I (ng/L) | 3.0 [2.0, 10.0] | 3.0 [2.0, 9.0] | 5.0 [3.0, 19.5] | <0.001 |
| Admission drugs | ||||
| Aspirin | 180 (17.5) | 130 (14.5) | 50 (37.6) | <0.001 |
| Clopidogrel | 81 (7.9) | 62 (6.9) | 19 (14.3) | 0.005 |
| Beta-blockers | 149 (14.5) | 109 (12.1) | 40 (30.1) | <0.001 |
| ACE-I/ARB | 189 (18.3) | 143 (15.9) | 46 (34.6) | <0.001 |
| Statin | 249 (24.2) | 192 (21.4) | 57 (42.9) | <0.001 |
| Warfarin | 44 (4.3) | 35 (3.9) | 9 (6.8) | 0.195 |
| PPI | 233 (22.6) | 184 (20.5) | 49 (36.8) | <0.001 |
| Admission electrocardiogram | ||||
| ST elevation | 13 (2.0) | 5 (1.0) | 8 (6.0) | 0.001 |
| ST depression | 21 (3.2) | 9 (1.7) | 12 (9.0) | <0.001 |
| T-wave inversion | 58 (8.9) | 34 (6.5) | 24 (18.0) | <0.001 |
| New LBBB | 11 (1.7) | 5 (1.0) | 6 (4.5) | 0.014 |
| Old LBBB | 17 (2.6) | 13 (2.5) | 4 (3.0) | 0.982 |
| RBBB | 21 (3.2) | 15 (2.9) | 6 (4.5) | 0.501 |
| Management | ||||
| Chest pain nurse referral | 36 (3.4) | 5 (0.5) | 31 (22.8) | <0.001 |
| Cardiology referral | 50 (4.8) | 14 (1.5) | 36 (26.5) | <0.001 |
| Admitted to hospital | 609 (58.2) | 512 (56.2) | 97 (71.3) | 0.001 |
| Echocardiogram | 17 (1.6) | 5 (0.5) | 12 (8.8) | <0.001 |
| Coronary angiogram | 17 (1.6) | 2 (0.2) | 15 (11.0) | <0.001 |
| PCI | 10 (1.0) | 0 (0.0) | 10 (7.4) | <0.001 |
| CABG | 1 (0.1) | 0 (0.0) | 1 (0.7) | 0.27 |
| Discharge drugs | ||||
| Aspirin | 192 (18.8) | 131 (14.7) | 61 (45.5) | <0.001 |
| Clopidogrel | 102 (10.0) | 69 (7.8) | 33 (24.6) | <0.001 |
| Beta-blockers | 152 (14.9) | 106 (11.9) | 46 (34.3) | <0.001 |
| ACEI/ARB | 181 (17.7) | 134 (15.1) | 47 (35.1) | <0.001 |
| Statin | 256 (25.0) | 192 (21.5) | 64 (47.8) | <0.001 |
| Warfarin | 44 (4.3) | 33 (3.7) | 11 (8.2) | 0.03 |
| Proton pump inhibitor | 246 (24.0) | 193 (21.7) | 53 (39.6) | <0.001 |
Values are n (%), mean ± SD or median [IQR]
Abbreviations: bpm=breaths/beats per minute; BP=blood pressure; PCI= percutaneous coronary intervention, CABG=coronary artery bypass grafting, ACE-I/ARB=angiotensin converting enzyme inhibitor/ angiotensin receptor blocker, PPI=proton pump inhibitor
⁎
Consists of all patients with troponin levels above the 99th percentile upper reference limit using sex specific diagnostic thresholds including those further classified as type 1 and type 2 myocardial infarction