Left ventricular non-compaction (LVNC) is characterized by prominent left ventricular trabeculae and deep inter-trabecular recesses. The myocardial wall is often thickened with a thin, compacted epicardial layer and a thickened endocardial layer. In some patients, LVNC is associated with left ventricular dilatation and systolic dysfunction, which can be transient in neonates. The phenotype is Left ventricular noncompaction cardiomyopathy (HP_0011664). Also known as: Left ventricular non-compaction cardiomyopathy.