Reproducibility, interobserver variability, and intraobserver variability
| Variable | Interobserver variability (%) | Intraobserver variability (%) | Reproducibility (%) |
| LAD diameter (mm) | 3.7 | 3.2 | 4.1 |
| IVST (mm) | 3.3 | 2.2 | 3.6 |
| LVID (mm) | 3.5 | 3.1 | 4.3 |
| PWT (mm) | 4.6 | 3.5 | 4.8 |
| LVM (g) | 5.1 | 4.5 | 6.1 |
| Resting peak diastolic velocity (m/s) | 4.7 | 2.8 | 5.8 |
| Resting velocity–time integral (mm) | 3.7 | 3.0 | 3.8 |
| Resting LAD flow (ml/min) | 5.5 | 4.1 | 6.8 |
| Resting LAD flow (ml/min/100 g LV) | 5.8 | 4.8 | 7.5 |
| Hyperaemic peak diastolic velocity (m/s) | 5.0 | 4.1 | 12.1 |
| Hyperaemic velocity time integral (mm) | 3.9 | 3.6 | 14.1 |
| Hyperaemic LAD flow (ml/min) | 6.5 | 4.5 | 8.2 |
| Hyperaemic LAD flow (ml/min/100 g LV) | 6.7 | 5.1 | 7.8 |
| Coronary flow reserve | 5.8 | 3.8 | 9.1 |
IVST, interventricular septal thickness; LAD, left anterior descending coronary artery; LV, left ventricle; LVID, left ventricular internal diameter; LVM, left ventricular mass; PWT, posterior wall thickness.