Pediatric ECGs

A excellent description of the neonatal electrocardiogram has been made by Schwarz et al.schwarz1schwarz2

Heart Axis

Normal heart axis valuesaha

Age	QRS Axis Normal Values	Abnormal Values	Description
Adult	-30° to 90°	<-30° -30° to -45° -45° to -90° 90° to 120° 90° to 180°	Left-axis deviation Moderate left-axis deviation Marked left-axis deviation Moderate right-axis deviation Marked right-axis deviation
8 to 16 years	0° to 120°	>120°	Right-axis deviation
5 to 8 years	0° to 140°	>140° <0°	Right-axis deviation Left-axis deviation
1 year to 5 years	5° to 100°	>100°	Right-axis deviation
1 mo to 1 y	10° to 120°	>120° <10° to -90°	Right-axis deviation Left-axis deviation
Neonate	30° to 90°	>190° to -90° <30° to <-90°	Extreme right axis deviation Left axis deviation

Conduction

RBBB: if consistent morphology and if QRS width >90ms in children < 4 years and >100ms in children 4-16 yearsaha LBBB: if consistent morphology and QRS width >90ms in children < 4 years and >100ms in children 4-16 yearsaha

Normal neonatal ECG standards

Normal neonatal ECG standards

Age group	Heart rate (beats . min-1)	Frontal plane QRS axisa (degrees)	P wave amplitude (mm)	P-R intervala (s)	QRS durationa V5	Q IIIc (mm)	QV6c (mm)	RV1b (mm)	SV1b (mm)	R/S V1c	RV6b (mm)	SV6b (mm)	R/S V6c	SV1 + RV6c (mm)	R + SV4c (mm)
0–1 days	93–154 (123)	+59 to +192 (135)	2·8	0·08–0·16 (0·11)	0·02–0·08 (0·05)	5·2	1·7	5–26	0–22·5	9·8	0–11	0–9·8	10	28	52
1–3 days	91–159 (123)	+64 to +197 (134)	2·8	0·08–0·14 (0·11)	0·02–0·07 (0·05)	5·2	2·1	5–27	0–21	6	0–12	0–9·5	11	29	52
3–7 days	90–166 (129)	+77 to +187 (132)	2·9	0·08–0·14 (0·10)	0·02–0·07 (0·05)	4·8	2·8	3–24	0–17	9·7	0·5–12	0–9·8	10	25	48
7–30 days	107–182 (149)	+65 to +160 (110)	3·0	0·07–0·14 (0·10)	0·02–0·08 (0·05)	5·6	2·8	3–21·5	0–11	7	2·5–16	0–9·8	12	22	47
1–3 months	121–179 (150)	+31 to +114 (75)	2·6	0·07–0·13 (0·10)	0·02–0·08 (0·05)	5·4	2·7	3–18·5	0–12·5	7·4	5–21	0–7·2	12	29	53
a 2nd–98th percentile (mean) b 2nd–98th percentile (1 mm=100 µV) c 98th percentile (1 mm=100 µV)

References

<biblio>

1. aha pmid=19228822
2. schwarz1 pmid=12269267
3. schwarz2 pmid=12739597

</biblio>