Baseline characteristics of the mechanism cohort by tertile of cMyC and controls
| All (n=161) | Tertile 1 3–16 ng/L (n=54) | Tertile 2 17–28 ng/L (n=55) | Tertile 3 29–171 ng/L (n=52) | P value | Controls (n=46) | |
| Age (years) | 68.5 (11.4) | 64.3 (13.0) | 69.4 (9.3) | 71.8 (10.5) | 0.002 | 57.9 (20.5) |
| Sex (male), n (%) | 112 (69.6) | 29 (53.7) | 42 (76.4) | 41 (78.8) | 0.008 | 29 (63.0) |
| BMI (kg/m2) | 28.9 (4.8) | 29.1 (5.2) | 28.7 (4.0) | 29.0 (5.1) | 0.88 | 26.8 (3.8) |
| BSA (m2) | 1.9 (0.2) | 1.9 (0.2) | 1.9 (0.2) | 1.9 (0.2) | 0.71 | 1.9 (0.2) |
| Comorbidity | ||||||
| Diabetes mellitus, n (%) | 24 (14.9) | 9 (16.7) | 6 (10.9) | 9 (17.3) | 0.59 | 0 (0.0) |
| Hypertension, n (%) | 109 (67.7) | 30 (55.6) | 42 (76.4) | 37 (71.2) | 0.06 | 12 (26.1) |
| Hyperlipidaemia, n (%) | 72 (44.7) | 20 (37.0) | 22 (40.0) | 30 (57.7) | 0.07 | 8 (17.4) |
| IHD, n (%) | 61 (37.9) | 12 (22.2) | 23 (41.8) | 26 (50.0) | 0.01 | 2 (4.3) |
| Previous PCI, n (%) | 25 (15.5) | 6 (11.1) | 8 (14.5) | 11 (21.2) | 0.35 | 2 (4.3) |
| Previous CABG, n (%) | 7 (4.4) | 2 (3.7) | 1 (1.9) | 4 (7.7) | 0.33 | 0 (0.0) |
| Medications | ||||||
| Antiplatelet, n (%) | 79 (49.1) | 17 (31.5) | 29 (52.7) | 33 (63.5) | 0.004 | 7 (15.2) |
| ACE-I/ARB, n (%) | 67 (41.6) | 16 (29.6) | 28 (50.9) | 23 (44.2) | 0.07 | 9 (19.6) |
| Beta blocker, n (%) | 55 (34.2) | 16 (29.6) | 17 (30.9) | 22 (42.3) | 0.32 | 5 (10.9) |
| Diuretic, n (%) | 52 (32.3) | 16 (29.6) | 21 (38.2) | 15 (28.8) | 0.51 | 4 (8.7) |
| Blood tests | ||||||
| Creatinine (μmol/L) | 79.1 (17.1) | 73.5 (11.1) | 78.6 (15.5) | 85.2 (21.5) | 0.002 | 72.5 (15.3) |
| eGFR (mL/min/1.73 m2) | 86.3 (18.5) | 89.0 (15.9) | 88.0 (18.8) | 81.7 (20.1) | 0.09 | 97.7 (19.8) |
| Troponin I (ng/L) | 6.6 (3.8–12.3) | 3.3 (2.3–4.5) | 6.7 (4.8–9.5) | 15.5 (10–30.2) | <0.001 | 2.7 (1.1–5.4) |
| Echo parameters | ||||||
| AVmax (m/s) | 3.8 (0.9) | 3.4 (0.8) | 3.9 (0.8) | 4.3 (0.9) | <0.001 | 1.4 (0.2) |
| AV area (cm2) | 1.0 (0.4) | 1.1 (0.4) | 0.9 (0.3) | 0.9 (0.4) | 0.006 | 2.4 (0.6) |
| AV MPG (mm Hg) | 34.4 (18.6) | 25.9 (13.5) | 34.5 (16.6) | 43.2 (21.3) | <0.001 | 4.2 (1.4) |
| Indexed LV mass (g/m2) | 122.7 (32.0) | 102.3 (22.8) | 127.6 (27.3) | 139.4 (33.7) | <0.001 | 93.2 (24.4) |
| E/e′ | 14.6 (7.6) | 12.4 (4.8) | 13.1 (5.0) | 18.3 (10.4) | <0.001 | 8.6 (2.5) |
| MRI parameters | ||||||
| Indexed LV mass (g/m2) | 88.8 (21.5) | 74.2 (15.2) | 90.1 (16.6) | 102.5 (22.1) | <0.001 | 65.8 (13.7) |
| Ejection fraction (%) | 66.8 (7.3) | 67.5 (5.6) | 65.8 (8.3) | 67.2 (7.8) | 0.44 | 64.4 (4.4) |
| Indexed SV (mL/m2) | 47.6 (10.2) | 44.3 (8.4) | 47.1 (9.6) | 51.4 (11.2) | 0.001 | 46.1 (8.2) |
| Indexed ESV (mL/m2) | 24.2 (9.8) | 21.6 (6.6) | 25.5 (11.5) | 25.6 (10.2) | 0.055 | 26.0 (7.4) |
| Indexed EDV (mL/m2) | 71.8 (16.9) | 65.9 (13.3) | 72.6 (17.8) | 77.0 (17.8) | 0.003 | 72.1 (14.6) |
| ECV (%) | 27.8 (2.6) | 27.1 (2.2) | 27.4 (2.1) | 28.9 (3.2) | 0.001 | 26.6 (1.7) |
| Fibrosis volume (g) | 44.6 (15.3) | 36.0 (8.9) | 44.2 (11.1) | 54.5 (18.5) | <0.001 | 31.0 (7.6) |
| Outcomes | ||||||
| AVR, n (%) | 41 (25.5) | 8 (14.8) | 20 (36.4) | 13 (25.0) | 0.04 | 0 (0.0) |
| Cardiac death, n (%) | 1 (0.6) | 0 (0.0) | 0 (0.0) | 1 (1.9) | 0.35 | 0 (0.0) |
| All-cause death, n (%) | 6 (3.7) | 1 (1.9) | 1 (1.8) | 4 (7.7) | 0.19 | 0 (0.0) |
Values are number (%), mean (SD) or median (IQR). Results in bold are statistically significant.
ACE-I, ACE inhibitor; ARB, angiotensin receptor blocker; AV, aortic valve; AVR, aortic valve replacement.; BMI, body mass index; BSA, body surface area; CABG, coronary artery bypass grafting; cMyC, cardiac myosin-binding protein C; ECV, extracellular volume fraction; EDV, end-diastolic volume; eGFR, estimated glomerular filtration rate; ESV, end-systolic volume; IHD, ischaemic heart disease; PCI, percutaneous coronary intervention; LV, left ventricle; MPG, mean pressure gradient; SV, stroke volume.