The ECG of children is different from adults due to developmental changes. As children age, their heart rate decreases while measurements like P-wave duration and QRS duration increase. In newborns, the right ventricle dominates but over the first year the left ventricle becomes the dominant chamber. The T-wave also changes significantly in infants in the first week of life as right ventricular pressure changes. Premature infants have shorter ECG intervals and less right ventricular dominance compared to full-term infants.

1. ECG IN CHILDREN:
HOW IS IT DIFFERENT FROM ADULTS?
MURTAZA KAMAL
MURTAZA.VMMC@GMAIL.COM
11/SEPT/2018
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3. DEVELOPMENTAL CHANGES
• Decrease in HR
• Increase in P-wave duration, PR interval, QRS duration
• QRS Voltage: Low during 1st several months
• QRS voltages: Low during first several months
• Mean QRS axis in frontal plane: Moves from right to left
• Increase in PR interval+ QRS duration: Changes in size of heart /AV node
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4. VENTRICULAR DOMINANCE
• Newborn: QRS potentials result from RVRV dominance
• Transition of ECG from RV dominance at birth to pattern of LV: Lags behind
hemodynamic changes
• Loss of RV dominance:
• Starts at 1 month of age
• LV dominance is well established by 1 year
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5. VENTRICULAR DOMINANCE
• 1st several weeks:
• Tall R+ small S in right and anterior precordium: V3R, V4R, and V1
• Deep S+ small R in left precordium: V6 and V7
• Corresponds to clockwise vector loop in horizontal plane
• 2 months of age:
• Precordial leads progress to more adult pattern
• Deeper S waves in right and taller R waves in left leads
• Counterclockwise vector loop in horizontal plane
• 1 year: Precordial R wave progression similar to adults
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6. T WAVE CHANGES
• Rapid changes of RV pressure after birth: Great effect on T wave
• 1st minutes after birth, T-wave vector: Anterior and to left i.e upright in V1+ V6
• May swing rightward in next several hours: Flattening/ inversion of T in left
lateral leads
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7. T WAVE CHANGES
• Next 7 days:
• T-wave vector moves posterior+ leftward
• Inverted T in V1+ upright T in V6
• After 7- 8 years: Becomes upright again in V1
• May remain inverted throughout adolescence: Juvenile T-wave pattern
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8. A FEW WORDS ABOUT PRE-TERM INFANT
• Notable for its shorter QRS duration, PR interval and QT interval
• Less RV dominance at birth than ECG of full-term infant
• Precordial voltages: Lower in 1-year-old infant who was premature
• Intrinsic myocardial differences of premature or to altered cardiac–torso
geometry: Unknown
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9. THANK YOU
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