| AF | Atrial fibrillation |
| CRT-D | Cardiac resynchronization therapy defibrillator |
| CRT% | Percentage of cardiac resynchronization therapy pacing |
| DDAF | Device-detected atrial fibrillation |
| HF | Heart failure |
| HFrEF | HF with reduced ejection fraction |
| HRV | Heart rate variability |
| ICD | Implantable cardioverter-defibrillator |
| nHR | Nocturnal heart rate |
| PVC/h | Frequency of premature ventricular contractions per hour |
| VA | Ventricular arrhythmia |
| 24 h-HR | Mean heart rate over 24 h |
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