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Hypersensitivity myocarditis presenting as atrioventricular block and wide complex tachycardia in a toddler

Neil Bhogal1, Anita Moon Grady, Philip C Ursell

  • 1University of California San Francisco, Pediatric Cardiology, San Francisco, CA 94143-0214, USA.

Congenital Heart Disease
|October 8, 2008
PubMed

Insights

A rare case of eosinophilic myocarditis in an infant caused complete atrioventricular block and wide complex tachycardia. The condition resolved spontaneously, highlighting a unique presentation of pediatric hypersensitivity myocarditis.

Area of Science:

  • Pediatric Cardiology
  • Immunology
  • Pathology

Background:

  • Eosinophilic myocarditis is a rare inflammatory condition affecting the heart muscle.
  • Hypersensitivity reactions can trigger eosinophilic myocarditis, particularly in young children.
  • Atrioventricular block and tachycardia are serious cardiac arrhythmias that require prompt diagnosis.

Observation:

  • A 13-month-old boy presented with sudden onset of complete atrioventricular block and wide complex tachycardia.
  • Hemodynamics remained stable despite the severe cardiac rhythm disturbance.
  • Endomyocardial biopsy revealed active myocarditis characterized by eosinophilic infiltration.

Findings:

  • The patient's presentation was unique, with a self-limited course of rhythm disturbance.
  • The findings suggest a hypersensitivity reaction as the likely cause of myocarditis.
  • This is only the second reported case of eosinophilic myocarditis in an infant or young child.

Implications:

  • This case expands the understanding of rare causes of pediatric cardiac arrhythmias.
  • It underscores the importance of considering hypersensitivity reactions in unexplained myocarditis.
  • Further research is needed to elucidate the mechanisms and long-term outcomes of eosinophilic myocarditis in children.

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