Prenatal diagnosis of isolated non-compaction of the ventricular myocardium: study of six cases.

Background: Isolated non-compaction of the ventricular myocardium (INVM) is characterized by prominent and excessive trabeculations in one or more ventricular wall segments, with deep intertrabecular recesses communicating directly with the ventricular cavities. Diagnosis of the disease is based on the 2-D echocardiographic features. Despite the fact that many cases of INVM have been reported in children and adults since the initial description of the disease, it has been diagnosed in only a few fetuses up to now. Therefore, failure to diagnose on fetal echocardiography is probably more common. There are different opinions about diagnosis of INVM on fetal echocardiography.

Method: In the present study, six cases of fetal INVM diagnosed between 1999 and 2004 were evaluated for prenatal diagnosis, clinical features and natural course.

Results: In four cases, diagnosis was made in the prenatal period, and in the other two cases it was done on postnatal echocardiography at the first day of life. Careful reevaluation of these two patient's fetal echocardiographic recordings confirmed the postnatal diagnosis retrospectively.

Conclusions: The examiner should be aware of the existence of this rare anomaly. If echocardiographic examination shows ventricular hypertrophy and/or poor ventricular function, INVM should be considered and in order to see recesses, ventricle walls should be investigated by zooming in and comparing frame by frame.