Clinical features of isolated noncompaction of the myocardium in children.

Isolated noncompaction of the myocardium, also known as "spongy myocardium", is a rare disease in children and adults. It is suggested that, during early development of the heart, the primary spongy structure persists due to an arrest of compaction. No other cardiac malformations are found, but there are familial occurences, relations to genetic disorders or syndromes such as Melnick-needles-syndrome or Xq28-linked cardiomyopathy, and reports of conduction disorders. We have now diagnosed isolated noncompaction in seven children aged between five weeks and 5.5 years. Three are doing well with anticongestive therapy, while transplantation of the heart was performed in one. Three of the children have died, but in only one case due to cardiac failure. Our experience emphasises the need rapidly to establish the diagnosis, to search for associated extracardiac abnormalities, and to consider transplantation at an early stage.