Objectives There is not yet a general consensus about the diagnosis of left ventricular noncompaction. The echocardiographer may miss the areas with maximal noncompaction leading to a misdiagnosis. Accordingly, we suggested a new method to measure the percentage of myocardial hypertrabeculation/noncompaction using two-dimensional echocardiography.

Patients In this study, this new method was examined on 3 noncompaction, 26 dilated cardiomyopathy, and 25 normal subjects.

Results The mean percentages of myocardial hypertrabeculation/noncompaction were 3.59±2.27 in control group, 8.86±5.52 in dilated cardiomyopathic patients, and 38.1±30.8 in noncompaction patients. A value of 16% could distinguish left ventricular noncompaction from dilated cardiomyopathy with 92% specificity and 100% sensitivity and from normal subjects with 100% specificity and sensitivity. This percentage had a statistically significant association with noncompacted to compacted myocardial thickness ratio (P<0.001).

Key conclusions This method showed good correlations with the other echocardiographic and magnetic resonance criteria. However, it is not dependent on finding the area of maximal involvement.