What is the management and evaluation approach for a newborn with right axis deviation on an electrocardiogram (ECG)?

Management and Evaluation of Newborn Right Axis Deviation

Right axis deviation on an electrocardiogram (ECG) in a newborn is typically a normal finding and generally requires no specific intervention, as the normal QRS axis in full-term neonates ranges between 55° and 200°. 1

Normal Axis Values in Neonates

• The normal full-term neonate has a QRS axis between 55° and 200°, which gradually shifts leftward with age 1
• By 1 month of age, the normal upper limit falls to 160° or less 1
• In premature newborns, the QRS axis normally ranges between 65° and 174° 1
• What would be considered right axis deviation in adults (e.g., 120°) is a normal finding in newborns 1

Initial Assessment

• Determine the exact QRS axis measurement to confirm it falls within normal range for age 1
• Evaluate the ECG for other abnormalities that might indicate underlying pathology 1
• Look for any clinical signs or symptoms suggesting cardiovascular disease 1
• Consider the following when interpreting neonatal ECGs:
  • QRS duration in newborns should be narrow (<80 ms) 1
  • QRS morphology in newborns may normally have more notches and direction changes than in older children or adults 1
  • Artifacts are common in neonatal ECGs and should be ruled out 1

When to Consider Further Evaluation

Further cardiac evaluation should be considered in the following situations:

• QRS axis beyond the normal range for age (>200° in neonates) 1
• Presence of other ECG abnormalities suggesting congenital heart disease 1
• Clinical signs or symptoms of cardiovascular disease 1
• Family history of congenital heart disease or sudden cardiac death 1

Diagnostic Workup When Indicated

If the right axis deviation is beyond the normal range or associated with concerning features:

• Complete 2-dimensional echocardiography to rule out structural heart defects 1
• Additional ECG leads (V3R, V4R, and V7) may provide additional information to evaluate possible congenital heart lesions 1
• Consider evaluation for specific congenital heart defects associated with extreme right axis deviation:
  • Tetralogy of Fallot 2
  • Ebstein's anomaly 1
  • Atrioventricular septal defects 3

Common Pitfalls to Avoid

• Misinterpreting normal neonatal right axis as pathological by applying adult criteria 1
• Failing to consider age-related changes in QRS axis 1
• Not recognizing artifacts common in neonatal ECGs (limb lead reversal, incorrect chest lead positioning, electrical interference, movement artifacts) 1
• Overdiagnosis of axis deviation as a primary diagnosis rather than a finding that requires clinical correlation 4

Follow-up Recommendations

• For isolated right axis deviation within normal range for age without other abnormalities:
  • No specific follow-up is needed as this is a normal finding 1
• For borderline or concerning axis deviation:
  • Repeat ECG at 1 month of age to assess if axis is shifting appropriately leftward 1
  • If axis remains abnormal or other concerns develop, refer to pediatric cardiology 1

Special Considerations

• Hereditary patterns of right axis deviation have been reported and may not indicate pathology if no structural abnormalities are found 5
• In prenatal ultrasound, rightward deviation of the cardiac axis (>57°) may be associated with congenital heart defects and warrants detailed fetal echocardiography 6, 3