Different types of cardiomyopathy associated with isolated ventricular noncompaction

Abstract

Although mainly described in the context of dilated and hypokinetic left ventricles, it is unclear whether isolated ventricular noncompaction (IVNC) is a distinct cardiomyopathy, a subtype of dilated cardiomyopathy, or a morphogenetic disorder. To investigate the spectrum of cardiomyopathies associated with IVNC, children and adults with stringent echocardiographic diagnoses of IVNC were reviewed. Seventy-three patients (12 children aged <15 years) seen since 1994 satisfied stringent echocardiographic criteria for IVNC. Sixty-five patients (89%; 11 children) had dilated cardiomyopathy, 2 adults had clear-cut hypertrophic cardiomyopathy, 1 adult had restrictive cardiomyopathy (to the investigators' knowledge, the first reported example of this particular association), and 5 patients (1 child) had normal left ventricular morphology and function. In conclusion, knowledge that IVNC can co-exist with restrictive and hypertrophic cardiomyopathy (in addition to the dilated form) supports the concept that IVNC is a morphologic trait rather than a distinct cardiomyopathy. This knowledge should be taken into account during echocardiographic examination and encourage the use of contrast echocardiography (and magnetic resonance) and could also orient molecular biology studies.