Noncompaction cardiomyopathy

**Definition:** Noncompaction cardiomyopathy is a morphologic abnormality of the myocardium predominantly affecting the apex of the ventricle characterised by hypertrabeculation and deep inter-trabecular recesses, usually accompanied by an abnormally thin subepicardial layer of compacted myocardium, that is generally but not always associated with ventricular dysfunction.

Additional information. Noncompaction cardiomyopathy classically involves the left ventricle but can also involve only the right ventricle or both. It can occur as an isolated finding or in association with a dilated, hypertrophic, or mixed cardiomyopathic phenotype. It has been described in association with complex congenital heart disease, coronary artery anomalies and as an isolated finding, with and without musculoskeletal and other system abnormalities.

**Long definition:** Noncompaction cardiomyopathy classically involves the left ventricle but can also involve only the right ventricle or both. It can occur as an isolated finding or in association with a dilated, hypertrophic, or mixed cardiomyopathic phenotype. It has been described in association with complex congenital heart disease, coronary artery anomalies and as an isolated finding, with and without musculoskeletal and other system abnormalities.