Isolated non-compaction of the ventricular myocardium (INVM), sometimes referred 
to as 'spongy myocardium', is a congenital and exceedingly rare cardiomyopathy. 
Isolated ventricular non-compaction occurs in the absence of other structural 
heart diseases and, hypothetically, it is due to the arrest of myocardial 
morphogenesis. Isolated non-compaction of the ventricular myocardium may 
manifest itself from infancy to young adulthood with a high mortality rate. Both 
sexes are affected. In our study, we present a case of INVM (left and right 
ventricles) in a 3-year-old girl, diagnosed by two-dimensional echocardiography. 
The anomaly presented as a restrictive cardiomyopathy. The girl was admitted to 
our hospital with heart failure, when she was 10 months old. She was treated 
with dopamine, digoxin, furosemide, spironolactone, and acenocoumarol and her 
condition improved. Presently, the girl remains asymptomatic and for 3 years of 
follow-up, her development has been almost normal. We here describe the genetic 
background of this disorder (based on a literature review).