Reference (normal) values for pediatric & neonatal ECG interpretation

Neonatal period

Table 1. Normal limits for ECG parameters during neonatal period (Davignon et al)

These reference values are the best available for the neonatal period. The intervals are 98% confidence intervals (the mean is presented in the parenthesis). Values without confidence interval are simply the 98th percentile (i.e the upper reference limit).

Age<1 day1–3 days3–7 days7–30 days1–3 months3–6 months6–12 months1–3 years3–5 years5–8 years8–12 years12–16 years>16 years
Heart rate (beats per minute)93–155 (122)91–158 (124)90–166 (128)106–182 (148)120–179 (149)105–185 (142)107–168 (132)90–151 (119)73–137 (108)65–133 (100)63–129 (92)66–120 (86)50 – 120
Electrical axis (degrees)58–168 (>135)65–171 (>134)76–168 (>133)65–159 (110)31–115 (75)7–105 (60)7–98 (54)8–100 (55)7–104 (55)10–140 (66)9–115 (61)11–133 (58)-15 – 110
QRS duration21–7622–6721–6822–7923–7522–7923–7627–7530–7232–7932–8534–880.05 – 0.10
PR interval79–160 (107)81–139 (108)75–137 (104)73–138 (101)73–130 (98)74–145 (106)73–156 (156)82–148 (114)85–161 (118)90–164 (124)87–171 (128)92–175 (135)0.12 – 0.20
Q-wave in III (mm)0.1–50.1–50.1–50.1–50.1–5<6.6<6.3<5.3<4.2<3.2<2.7<3.0<3
R-wave in V1 (mm)5–27 (14)5–27 (15)3–25 (13)3–22 (11)3–19 (10)3–20 (10)2–20 (9)3–18 (9)2–18 (8)1–13 (7)0.5–10 (6)0.5–10 (5)0.5 – 14
S-wave in V1 (mm)0.5–23 (9)0.5–21 (10)0.5–17 (7)0.5–12 (4)0.5–13 (5)0.5–17 (6)0.5–18 (7)1–21 (9)2–22 (10)3–24 (12)3–26 (12)3–22 (11)0.5 – 23
R/S-ratio in V10.2–9.8 (2.3)0.2–6.0 (2.0)0.2–9.8 (2.8)1.0–7.0 (2.9)0.3–7.5 (2.3)0.2–6.0 (2.4)0.1–3.9 (1.8)0.1–4.2 (1.4)0–2.8 (0.9)0–2.0 (0.8)0–1.9 (0.6)0–1.8 (0.5)
R-wave in V6 (mm)0–12 (5)0.1–12 (5)0.5–12 (5)3–17 (8)5–22 (12)6–23 (14)6–23 (13)6–23 (14)9–25 (15)9–27 (17)10–26 (17)7–23 (15)4 – 21
S-wave in V6 (mm)0.2–10 (4)0.2–10 (3)0.4–10 (4)0.2–10 (3)0.3–7 (3)0.2–10 (3)0.2–8 (2)0.1–7 (2)0.1–6 (2)0.1–4 (1)0.0–4 (1)0–4 (1)0 – 4
R/S-ratio in V60.5–9 (2.5)0.5–11 (3)0.5–10 (2.5)0.5–12 (4)0.5–12 (4.5)0.5–18 (6.5)0.5–22 (8)0.5–28 (9.5)0.8–30 (11)1–30 (12)2–33 (14)2–39 (15)

Childhood, overview

Table 2. Reference values for the most important parameters (Rijnbeek et al)

Numbers are medians with 2nd and 98th percentile in parenthesis. These numbers were published by Rijnbeek et al and are currently the most reliable for patients aged 1 month to 16 years. Reference values for patients aged <1 month are less reliable due to the small sample size in Rijnbeek et al. Therefore, Davignon et al is preferred for patients aged <1 month.

  0–1 month1–3 months3–6 months6–12 months1–3 years3–5 years5–8 years8–12 years12–16 years
Heart rate (beats per minute)Boys160 (129, 192)152 (126, 187)134 (112, 165)128 (106, 194)119 (97, 155)98 (73, 123)88 (62, 113)78 (55, 101)73 (48, 99)
Girls155 (136, 216)154 (126, 200)139 (122, 191)134 (106, 187)128 (95, 178)101 (78, 124)89 (68, 115)80 (58, 110)76 (54, 107)
P-wave electrical axis (degrees)Boys56 (13, 99)52 (10, 73)49 (–5, 70)49 (9, 87)48 (–12, 78)43 (–13, 69)41 (–54, 72)39 (–17, 76)40 (–24, 76)
Girls52 (24, 80)48 (20, 77)51 (16, 80)50 (14, 69)47 (1, 90)44 (–6, 90)42 (–13, 77)42 (–15, 82)45 (–18, 77)
P-wave duration (ms)Boys78 (64, 85)79 (65, 98)81 (64, 103)80 (66, 96)80 (63, 113)87 (67, 102)92 (73, 108)98 (78, 117)100 (82, 118)
Girls79 (69, 106)78 (62, 105)78 (63, 106)80 (64, 07)83 (62, 104)84 (66, 101)89 (71, 107)94 (75, 114)98 (78, 122)
PR interval (ms)Boys99 (77, 120)98 (85, 120)106 (87, 134)114 (82, 141)118 (86, 151)121 (98, 152)129 (99, 160)134 (105, 174)139 (107, 178)
Girls101 (91, 121)99 (78, 133)106 (84, 127)109 (88, 133)113 (78, 147)123 (99, 153)124 (92, 156)129 (103, 163)135 (106, 176)
Electrical (QRS) axis (degres)Boys97 (75, 140)87 (37, 138)66 (–6, 107)68 (14, 122)64 (–4, 118)70 (7, 112)70 (–10, 112)70 (–21, 114)65 (–9, 112)
Girls110 (63, 155)80 (39, 121)70 (17, 108)67 (1, 102)69 (2, 121)69 (3, 106)74 (27, 117)66 (5, 117)66 (5, 101)
QRS duration (ms)Boys67 (50, 85)64 (52, 77)66 (54, 85)69 (52, 86)71 (54, 88)75 (58, 92)80 (63, 98)85 (67, 103)91 (78, 111)
Girls67 (54, 79)63 (48, 77)64 (50, 78)64 (52, 80)68 (54, 85)71 (58, 88)77 (59, 95)82 (66, 99)87 (72, 106)
QTc interval (ms, Bazzet’s formula)Boys413 (378, 448)419 (396, 458)422 (391, 453)411 (379, 449)412 (383, 455)412 (377, 448)411 (371, 443)411 (373, 440)407 (362, 449)
Girls420 (379, 462)424 (381, 454)418 (386, 448)414 (381, 446)417 (381, 447)415 (388, 442)409 (375, 449)410 (365, 447)414 (370, 457)

Childhood, P-waves

Table 3. Reference values for P-wave amplitude (Rijnbeek et al)

Numbers are median with 98th percentile (i.e the upper reference limit) in parenthesis. All values are millivolt (mV). Multiply by 10 to transform to millimeters (mm).

Lead 0–1 month1–3 months3–6 months6–12 months1–3 years3–5 years5–8 years8–12 years12–16 years
IIBoys0.15 (0.23)0.16 (0.25)0.15 (0.22)0.16 (0.26)0.15 (0.25)0.13 (0.23)0.12 (0.22)0.12 (0.22)0.13 (0.24)
Girls0.16 (0.25)0.16 (0.23)0.16 (0.23)0.16 (0.24)0.16 (0.25)0.13 (0.23)0.12 (0.24)0.14 (0.24)0.15 (0.26)
V1Boys0.12 (0.22)0.10 (0.19)0.09 (0.17)0.10 (0.17)0.13 (0.20)0.12 (0.19)0.12 (0.20)0.11 (0.19)0.11 (0.18)
Girls0.10 (0.19)0.10 (0.16)0.10 (0.16)0.11 (0.21)0.12 (0.20)0.12 (0.20)0.11 (0.18)0.11 (0.19)0.10 (0.17)

Childhood, Q-waves

Table 4. Reference values for Q-wave amplitude (Rijnbeek et al)

Numbers are median with 98th percentile (i.e the upper reference limit) in parenthesis. All values are millivolt (mV). Multiply by 10 to transform to millimeters (mm).

Lead 0–1 month1–3 months3–6 months6–12 months1–3 years3–5 years5–8 years8–12 years12–16 years
IIPojkar0.14 (0.23)0.18 (0.32)0.14 (0.34)0.18 (0.48)0.15 (0.44)0.11 (0.26)0.10 (0.28)0.09 (0.24)0.08 (0.21)
Flickor0.09 (0.26)0.14 (0.32)0.15 (0.43)0.16 (0.44)0.16 (0.48)0.13 (0.27)0.08 (0.26)0.08 (0.21)0.09 (0.20)
IIIPojkar0.15 (0.26)0.29 (0.50)0.31 (0.71)0.35 (0.79)0.30 (0.74)0.19 (0.46)0.15 (0.36)0.10 (0.28)0.10 (0.29)
Flickor0.18 (0.35)0.24 (0.50)0.28 (0.65)0.34 (0.79)0.31 (0.73)0.18 (0.40)0.16 (0.38)0.10 (0.27)0.10 (0.21)
aVFPojkar0.13 (0.23)0.20 (0.35)0.20 (0.40)0.22 (0.58)0.20 (0.54)0.14 (0.34)0.12 (0.25)0.09 (0.25)0.08 (0.23)
Flickor0.10 (0.27)0.17 (0.35)0.20 (0.44)0.23 (0.52)0.20 (0.54)0.12 (0.31)0.11 (0.31)0.08 (0.21)0.09 (0.18)
V6Pojkar0.11 (0.22)0.16 (0.31)0.17 (0.35)0.20 (0.60)0.20 (0.56)0.15 (0.42)0.12 (0.39)0.12 (0.43)0.11 (0.43)
Flickor0.09 (0.17)0.15 (0.37)0.15 (0.40)0.18 (0.39)0.17 (0.49)0.15 (0.42)0.10 (0.41)0.11 (0.34)0.09 (0.23)

Childhood, R-waves

Table 5. Normal limits for R-wave amplitude (Rijnbeek et al)

Numbers are median with 98th percentile (i.e the upper reference limit) in parenthesis. All values are millivolt (mV). Multiply by 10 to transform to millimeters (mm).

Lead 0–1 month1–3 months3–6 months6–12 months1–3 years3–5 years5–8 years8–12 years12–16 years
IBoys0.25 (0.45)0.56 (1.12)0.80 (1.52)0.82 (1.52)0.77 (1.37)0.63 (1.09)0.62 (1.16)0.59 (1.04)0.58 (1.09)
Girls0.31 (0.62)0.55 (1.09)0.74 (1.26)0.75 (1.38)0.68 (1.52)0.65 (1.20)0.49 (1.00)0.54 (1.21)0.48 (1.02)
IIBoys0.64 (1.28)1.08 (1.76)1.27 (1.97)1.27 (2.09)1.27 (2.47)1.36 (2.20)1.24 (2.42)1.39 (2.23)1.31 (2.08)
Girls0.70 (1.21)1.15 (2.04)1.33 (2.24)1.35 (2.21)1.27 (2.34)1.38 (2.24)1.33 (2.27)1.32 (2.29)1.32 (2.03)
IIIBoys0.79 (1.44)0.76 (1.60)0.72 (1.50)0.82 (1.65)0.80 (1.96)0.94 (1.82)0.80 (1.92)0.89 (1.86)0.85 (1.74)
Girls0.85 (1.50)0.91 (1.82)0.95 (1.85)0.90 (1.95)0.96 (2.00)0.94 (1.96)1.03 (2.09)0.92 (1.88)0.88 (1.66)
aVLBoys0.16 (0.32)0.35 (0.66)0.40 (1.09)0.44 (1.04)0.38 (0.86)0.26 (0.58)0.22 (0.70)0.17 (0.52)0.19 (0.69)
Girls0.18 (0.45)0.25 (0.69)0.37 (0.78)0.40 (0.92)0.38 (1.02)0.24 (0.70)0.18 (0.55)0.17 (0.69)0.16 (0.53)
aVFBoys0.59 (1.36)0.88 (1.58)0.93 (1.70)0.96 (1.81)1.00 (2.20)1.13 (1.97)1.00 (2.19)1.16 (2.00)1.06 (1.88)
Girls0.72 (1.26)0.98 (1.91)1.07 (1.82)1.11 (2.04)1.10 (2.08)1.14 (2.06)1.20 (2.17)1.09 (2.06)1.10 (1.84)
V3RBoys0.62 (1.04)0.58 (1.24)0.57 (1.20)0.48 (1.24)0.49 (1.06)0.41 (0.81)0.23 (0.63)0.22 (0.51)0.19 (0.54)
Girls0.68 (1.26)0.55 (0.93)0.49 (1.11)0.42 (0.98)0.43 (0.92)0.34 (0.64)0.21 (0.57)0.19 (0.47)0.17 (0.49)
V1Boys1.10 (2.05)1.23 (2.07)1.32 (2.20)1.12 (2.14)1.08 (2.11)0.95 (1.78)0.63 (1.48)0.54 (1.14)0.48 (1.18)
Girls1.35 (2.22)1.17 (1.99)1.14 (2.04)1.01 (1.92)1.01 (1.91)0.77 (1.38)0.55 (1.24)0.49 (1.14)0.35 (1.10)
V2Boys1.83 (2.67)1.82 (2.63)2.08 (2.54)1.94 (2.51)1.82 (2.41)1.58 (2.26)1.21 (2.22)1.02 (1.90)0.94 (1.87)
Girls1.83 (2.17)1.81 (2.45)1.88 (2.60)1.82 (2.36)1.75 (2.38)1.41 (2.25)1.06 (1.91)0.90 (1.86)0.69 (1.57)
V4Boys1.80 (2.62)2.30 (3.05)2.32 (3.23)2.27 (3.32)2.37 (3.38)2.42 (3.30)2.11 (3.11)1.86 (3.16)1.87 (3.06)
Girls1.68 (2.21)2.26 (3.26)2.26 (3.31)2.23 (3.09)2.21 (3.54)2.24 (3.38)1.84 (3.04)1.72 (3.23)1.24 (2.55)
V6Boys1.00 (1.78)1.55 (2.23)1.65 (2.73)1.70 (2.79)1.79 (2.96)1.94 (3.14)1.97 (2.98)2.18 (3.24)2.02 (3.05)
Girls0.93 (1.64)1.51 (2.67)1.60 (2.80)1.68 (2.74)1.68 (2.67)1.89 (2.91)2.05 (3.25)2.00 (3.04)1.65 (2.52)

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