Cohort characteristics
| Variable | AHRR <36 (n=181) | AHRR 36–46 (n=202) | AHRR 47–58 (n=197) | AHRR ≥59 (n=211) | p Value (across all groups) |
|---|---|---|---|---|---|
| Age (years) | 71.1 (0.8) | 69.1 (0.8) | 67.8 (0.9) | 63.9 (0.9) | <0.001 |
| Resting heart rate (bpm) | 70 (2) | 71 (1) | 73 (1) | 80 (1) | <0.001 |
| Systolic blood pressure (mm Hg) | 121 (2) | 121 (2) | 121 (2) | 123 (2) | 0.71 |
| QRS interval (ms) | 126 (2) | 125 (2) | 122 (2) | 116 (2) | 0.01 |
| Haemoglobin (g/dL) | 129 (1) | 136 (1) | 136 (1) | 142 (1) | <0.001 |
| Sodium (mmol/L) | 139 (1) | 139 (1) | 140 (1) | 140 (1) | 0.12 |
| eGFR (mL/Kg/1.73 m2) | 49 (1) | 54 (1) | 56 (1) | 61 (1) | <0.001 |
| LV ejection fraction (%) | 33 (1) | 32 (1) | 32 (1) | 31 (1) | 0.58 |
| Minimum 24 h heart rate (bpm) | 59 (1) | 58 (1) | 56 (1) | 57 (1) | 0.37 |
| Maximum 24 h heart rate (bpm) | 86 (1) | 98 (1) | 108 (1) | 133 (1) | <0.001 |
| Ambulatory heart rate range (bpm) | 28 (1) | 41 (1) | 52 (1) | 76 (1) | <0.001 |
| Male sex (% (n)) | 73.5 (133) | 73.8 (149) | 74.1 (146) | 73.5 (155) | 0.99 |
| Ischaemic aetiology (% (n)) | 79 (143) | 69.3 (140) | 66 (130) | 42.2 (89) | <0.001 |
| NYHA class | 0.12 | ||||
| I | 14.4 (26) | 17.9 (36) | 25.4 (50) | 24.3 (51) | |
| II | 48.1 (87) | 46.3 (93) | 39.6 (78) | 48.1 (101) | |
| III | 35.4 (64) | 33.3 (67) | 33.5 (66) | 26.7 (56) | |
| IV | 2.2 (4) | 2.5 (5) | 1.5 (3) | 1 (2) | |
| Any device therapy (% (n)) | 36.5 (66) | 32.2 (65) | 24.9 (49) | 20.4 (43) | 0.002 |
| Cardiac resynchronisation (% (n)) | 28.7 (52) | 28.7 (58) | 23.4 (46) | 19 (40) | 0.06 |
| Implantable defibrillator (% (n)) | 18.2 (33) | 13.4 (27) | 8.6 (17) | 9 (19) | 0.01 |
| Any atrial fibrillation or flutter (% (n)) | 22 (39) | 23.9 (48) | 30.4 (58) | 48.8 (100) | <0.001 |
| Non-sustained VT (% (n)) | 36.9 (65) | 35.8 (72) | 37.6 (71) | 47.1 (96) | 0.08 |
| Diabetes (% (n)) | 40.9 (74) | 28.7 (58) | 20.8 (41) | 14.7 (31) | <0.001 |
| β-blocker use (% (n)) | 82.3 (149) | 81 (162) | 77.2 (152) | 76.6 (160) | 0.42 |
| β-blocker dose (mg bisoprolol/day) | 4.0 (0.3) | 3.4 (0.2) | 3.6 (0.2) | 3.1 (0.2) | 0.088 |
| ACEi/ARB use (% (n)) | 86.7 (157) | 87 (174) | 91.4 (180) | 87.6 (183) | 0.45 |
| MRA use (% (n)) | 45.9 (83) | 43.5 (87) | 41.1 (81) | 32.1 (67) | 0.03 |
| Furosemide dose (mg/day) | 66 (4) | 56 (4) | 52 (4) | 40 (3) | <0.001 |
AHRR, ambulatory heart rate range; ACEi, ACE inhibitors; ARB, angiotensin receptor blockers; eGFR, estimated glomerular filtration rate; LV, left ventricular; MRA, mineralocorticoid receptor antagonist; NYHA, New York Heart Association; VT, ventricular tachycardia.