Table 2.
Electrocardiographic and echocardiographic characteristics of neonates with a WPW pattern and matched controls
| WPW (n = 17) | Matched controls (n = 68) | P-value | |
|---|---|---|---|
| Heart rate, bpm | 131 (119–137) | 140 (124–154) | NS |
| PR interval, ms | 80 (80–84) | 98 (90–104) | <0.001 |
| QRS axis, degrees | 106 (61–147) | 127 (104–148) | NS |
| QRS duration, ms | 74 (70–82) | 56 (50–60) | <0.00001 |
| QT interval, ms | 304 (292–320) | 282 (264–302) | <0.00001 |
| QTcBazett, ms | 449 (432–465) | 420 (405–442) | <0.00001 |
| Max amplitude R-V1, µV | 1562 (971–2304) | 1010 (765–1307) | <0.05 |
| Max amplitude S-V1, µV | 566 (280–1159) | 468 (314–898) | NS |
| Max amplitude R-V6, µV | 932 (571–1640) | 878 (615–1251) | NS |
| Max amplitude S-V6, µV | 546 (317–815) | 693 (551–1032) | <0.05 |
| Fractional shortening, % | 29.2 (27.9–32.4) | 31.1 (29.1–34.0) | NS |
| Ejection fraction, % | 59.0 (57.0–63.8) | 61.8 (58.9–65.6) | NS |
| IVSD, mm | 2.5 (2.3–2.7) | 2.3 (2.1–2.7) | NS |
| LVPWd, mm | 2.0 (1.9–2.3) | 2.0 (1.8–2.4) | NS |
| LVIDd, mm | 20.5 (19.1–20.9) | 20.1 (18.7–21.5) | NS |
| LVIDs, mm | 14.0 (13.3–14.8) | 13.8 (12.9–14.7) | NS |
| LA diameter, cm | 11.3 (10.0–12.2) | 12.1 (10.9–13.3) | NS |
| MV A velocity, m/s | 0.50 (0.47–0.59) | 0.55 (0.48–0.64) | NS |
| MV E velocity, m/s | 0.56 (0.50–0.62) | 0.60 (0.51–0.69) | NS |
| MPA flow velocity, m/s | 0.81 (0.75–0.89) | 0.89 (0.79–0.96) | NS |
Data displayed as medians (inter-quartile ranges). Significant values are marked with bold.
bpm, beats per minute; IVSD, interventricular septal diameter; LA, left atrium; LVIDd, left ventricular internal diameter end-diastole; LVIDs, left ventricular internal diameter end-systole; LVPWd, left ventricular posterior wall diameter end-diastole; MPA, main pulmonary artery; MV A, trans-mitral atrial peak inflow velocity; MV E, trans-mitral early peak inflow velocity; NS, not significant; WPW, Wolff–Parkinson–White.