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Severe reversible cardiomyopathy in four unrelated infants associated with mitochondrial DNA D-loop heteroplasmy

R G Boles1, C Luna, M Ito

  • 1Division of Medical Genetics, Childrens Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027, USA.

Pediatric Cardiology
|November 25, 2003
PubMed

Insights

Inherited mitochondrial DNA D-loop mutations can cause severe cardiomyopathy in children. This infantile multisystem disease may be reversible with supportive care for heart failure and catabolism.

Area of Science:

  • Pediatric Cardiology
  • Mitochondrial Medicine
  • Genetics

Background:

  • Inherited metabolic disorders are significant causes of pediatric cardiomyopathy.
  • Mitochondrial DNA (mtDNA) D-loop point heteroplasmy was previously identified in children at risk for mitochondrial disease.

Observation:

  • Four children with severe cardiomyopathy and congestive heart failure were identified.
  • These cases presented with additional anomalies suggestive of multisystem disease.

Findings:

  • The identified heteroplasmic point substitutions in the mitochondrial DNA D-loop were associated with severe cardiomyopathy.
  • Myocardial dysfunction significantly improved with supportive therapy targeting congestive failure and catabolism.

Implications:

  • Mitochondrial DNA D-loop heteroplasmy may serve as a biomarker for severe, infantile multisystem disease.
  • Early recognition and supportive treatment can lead to reversible outcomes in affected children.
  • This finding highlights the importance of considering metabolic causes in pediatric cardiomyopathy.

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