Table 1.
Baseline characteristics of trial participants stratified by peak cardiac troponin I level and study phase (standard care and after implementation of the high sensitivity assay). Values are number (percentage) unless stated otherwise
| Characteristics | Overall | No myocardial injury | Myocardial injury or infarction | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Reclassified by high sensitivity assay | Identified by contemporary assay | ||||||||||
| Standard care (n=18 978) | After implementation (n=29 304) | Standard care (n=14 862) | After implementation (n=23 060) | Standard care (n=720) | After implementation (n=1051) | Standard care (n=3396) | After implementation (n=5193) | ||||
| Median (IQR) age (years) | 62 (50-76) | 60 (4974) | 59 (47-73) | 57 (46-71) | 78 (66-85) | 78 (66-85) | 73 (61-83) | 71 (59-81) | |||
| Women | 9114 (48) | 13 448 (46) | 7042 (47) | 10 529 (46) | 612 (85) | 858 (82) | 1460 (43) | 2061 (40) | |||
| Presenting symptoms*: | |||||||||||
| Chest pain | 10 693 (80) | 23 847 (81) | 8677 (83) | 19 414 (84) | 373 (68) | 701 (67) | 1643 (68) | 3732 (72) | |||
| Dyspnoea | 748 (6) | 1427 (5) | 383 (4) | 724 (3) | 66 (12) | 136 (13) | 299 (12) | 567 (11) | |||
| Palpitations | 386 (3) | 883 (3) | 291 (3) | 700 (3) | 19 (3) | 53 (5) | 76 (3) | 130 (3) | |||
| Syncope | 829 (6) | 1666 (6) | 567 (5) | 1242 (5) | 42 (8) | 83 (8) | 220 (9) | 341 (7) | |||
| Other | 720 (5) | 1468 (5) | 490 (5) | 968 (4) | 50 (9) | 78 (7) | 180 (7) | 422 (8) | |||
| Medical history: | |||||||||||
| Myocardial infarction | 1969 (10) | 2245 (8) | 1353 (9) | 1482 (6) | 97 (13) | 122 (12) | 519 (15) | 641 (12) | |||
| Cerebrovascular disease | 1332 (7) | 1617 (6) | 877 (6) | 1038 (5) | 88 (12) | 122 (12) | 367 (11) | 457 (9) | |||
| Diabetes mellitus | 1572 (8) | 1946 (7) | 961 (6) | 1079 (5) | 95 (13) | 123 (12) | 516 (15) | 744 (14) | |||
| Previous revascularisation: | |||||||||||
| PCI | 1581 (8) | 2101 (7) | 1204 (8) | 1540 (7) | 66 (9) | 89 (8) | 311 (9) | 472 (9) | |||
| CABG | 349 (2) | 433 (1) | 238 (2) | 296 (1) | 18 (3) | 22 (2) | 93 (3) | 115 (2) | |||
| Drugs at presentation: | |||||||||||
| Aspirin | 5840 (31) | 7323 (25) | 4231 (28) | 5231 (23) | 300 (42) | 368 (35) | 1309 (39) | 1724 (33) | |||
| Dual antiplatelet therapy† | 843 (4) | 762 (3) | 583 (4) | 520 (2) | 41 (6) | 47 (4) | 219 (6) | 195 (4) | |||
| Statin | 8191 (43) | 11 175 (38) | 5994 (40) | 8112 (35) | 403 (56) | 557 (53) | 1794 (53) | 2506 (48) | |||
| ACE inhibitor or ARB | 6449 (34) | 9169 (31) | 4681 (31) | 6604 (29) | 317 (44) | 445 (42) | 1451 (43) | 2120 (41) | |||
| β blocker | 5739 (30) | 7434 (25) | 4183 (28) | 5383 (23) | 285 (40) | 373 (35) | 1271 (37) | 1678 (32) | |||
| Oral anticoagulant‡ | 1411 (7) | 1842 (6) | 938 (6) | 1220 (5) | 94 (13) | 144 (14) | 379 (11) | 478 (9) | |||
| Electrocardiogram§: | |||||||||||
| Normal | - | - | - | - | 77 (31) | 255 (38) | 209 (26) | 735 (26) | |||
| Myocardial ischaemia | - | - | - | - | 35 (14) | 91 (14) | 316 (39) | 1163 (42) | |||
| ST segment elevation | - | - | - | - | 7 (3) | 17 (3) | 137 (17) | 576 (21) | |||
| ST segment depression | - | - | - | - | 26 (11) | 57 (9) | 167 (21) | 551 (20) | |||
| Left bundle branch block | - | - | - | - | 20 (8) | 60 (9) | 77 (10) | 177 (6) | |||
| T wave inversion | - | - | - | - | 35 (14) | 78 (12) | 139 (17) | 421 (15) | |||
| Physiological variables: | |||||||||||
| Mean (SD) heart rate (beats/min) | - | - | - | - | 85 (28) | 87 (27) | 88 (29) | 84 (26) | |||
| Mean (SD) systolic blood pressure (mm Hg) | - | - | - | - | 144 (28) | 144 (28) | 136 (30) | 138 (30) | |||
| Haematology and clinical chemistry: | |||||||||||
| Mean (SD) haemoglobin (g/L) | 135 (22) | 136 (21) | 137 (20) | 138 (20) | 126 (22) | 124 (22) | 132 (26) | 133 (25) | |||
| eGFR (mL/min/1.73m2) | 55 (12) | 53 (13) | 56 (10) | 55 (11) | 47 (15) | 48 (15) | 48 (16) | 47 (16) | |||
| Median (IQR) peak cardiac troponin (ng/L) | 4 (2-16) | 4 (2-16) | 3 (1-6) | 3 (1-6) | 25 (20-35) | 27 (21-38) | 215 (62-1566) | 398 (87-3584) | |||
ACE=angiotensin converting enzyme; ARB=angiotensin receptor blockers; CABG=coronary artery bypass grafting; eGFR=estimated glomerular filtration rate; IQR=interquartile range; PCI=percutaneous coronary intervention; SD=standard deviation.
*
Missing in 4466 (12%) patients.
†
Combination of two drugs from aspirin, clopidogrel, prasugrel, or ticagrelor.
‡
Includes warfarin or direct oral anticoagulants.
§
Electrocardiographic findings and physiological variables only reported for those with elevated cardiac troponin levels.