ECG intervals, durations and voltages
| PR interval (ms) | 144±28 (range, 100–220) |
| QTc (corrected QT interval) (ms) | 471±70 (range, 321–654) |
| QRS duration (ms) | 94±19 (range, 62–160) |
| QRS voltage (mV) | |
| Limb lead (maximum) | 0.7±0.3 (range, 0.2–1.5) |
| Precordial lead (sV1/2+rV5/6) | 1.8±0.8 (range, 0.5–3.5) |
| Ratio of limb/precordial lead voltages | 0.47±0.43 (range, 0.11–3) |
| R progression (R wave amplitude in V3) (mV) | 0.7±0.5 (range, 0.15–3) |
| P-wave voltage (mV) | |
| Lead II | 0.01±0.006 (range, 0.005–0.03) |
| Lead V1 | 0.01±0.004 (range, 0.005–0.02) |