Table 1.
ECG indices in developing neonatal mice
| Parameter | PND2 | PND4 | PND6 | PND8 | PND10 | PND12 | PND14 |
|---|---|---|---|---|---|---|---|
| n = | 17 | 20 | 20 | 20 | 20 | 20 | 20 |
| HR (bpm) | 424 ± 62 | 475 ± 59 | 525 ± 69 | 583 ± 46 | 594 ± 74 | 666 ± 25 | 713 ± 35 |
| HRVar (ms) | 3.2 ± 2.6 | 4.2 ± 4.3 | 12.4 ± 14.4 | 11.3 ± 10.5 | 16.5 ± 13.6 | 19.9 ± 10.5 | 18.0 ± 12.9 |
| PR (ms) | 45.3 ± 7.9 | 37.5 ± 5.8 | 31.9 ± 4.5 | 27.8 ± 2.4 | 28.3 ± 5.7 | 25.3 ± 1.3 | 24.3 ± 1.5 |
| QRS (ms) | 14.7 ± 4.1 | 13.1 ± 3.0 | 11.9 ± 1.9 | 10.4 ± 1.2 | 10.3 ± 1.2 | 9.8 ± 1.1 | 8.9 ± 0.8 |
| QTc (ms) | 58.0 ± 5.6 | 54.5 ± 4.7 | 51.2 ± 4.5 | 45.5 ± 3.7 | 45.8 ± 4.7 | 43.8 ± 2.7 | 42.6 ± 2.1 |
| pNN6 (ms) | 0.4 ± 1.2 | 3.0 ± 11.7 | 16.3 ± 30.0 | 8.0 ± 17.2 | 13.7 ± 23.1 | 7.3 ± 11.4 | 3.1 ± 7.2 |
Heart rate (HR), heart rate variability (HRVar), PR interval, QRS interval, corrected QT interval (QTc), and percentage of adjacent intervals differing by greater than 6 ms (pNN6) are provided. Values are expressed as mean ± SD.