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Significance of a Q wave in lead I in the newborn

B W Robinson1, P C Anisman, S Sandhu

  • 1Section of Cardiology, St. Christopher's Hospital for Children, MCP/Hahnemann University, Philadelphia, Pennsylvania, USA.

The American Journal of Cardiology
|September 11, 1999
PubMed

Insights

In healthy newborns, a pure Q wave on an electrocardiogram (ECG) may indicate increased right ventricular mass, not heart muscle damage (myocardial infarction). This finding helps differentiate normal ECG variations from serious cardiac conditions in infants.

Area of Science:

  • Pediatric Cardiology
  • Neonatal Electrocardiography
  • Cardiac Physiology

Background:

  • Electrocardiograms (ECGs) are crucial for assessing cardiac health in newborns.
  • Q waves on ECGs can sometimes indicate myocardial infarction, a serious condition.
  • Interpreting ECG findings in neonates requires understanding unique physiological differences.

Purpose of the Study:

  • To investigate the cause of pure Q waves in lead I in healthy newborns.
  • To differentiate between physiological Q waves and those indicative of myocardial infarction in this population.
  • To propose an alternative explanation for pure Q waves in lead I in healthy neonates.

Main Methods:

  • Retrospective analysis of electrocardiograms from 11 healthy newborns.
  • Clinical evaluation to rule out myocardial infarction.
  • Correlation of ECG findings with neonatal cardiac physiology.

Main Results:

  • All 11 newborns presented with a pure Q wave in lead I on their ECGs.
  • None of the infants had clinical evidence of myocardial infarction.
  • The presence of pure Q waves in lead I was associated with healthy neonatal status.

Conclusions:

  • A pure Q wave in lead I in healthy newborns may be a normal variant.
  • Increased right ventricular mass in neonates is proposed as the cause.
  • This finding can help avoid misdiagnosis of myocardial infarction in infants.

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