Syndromic non‐compaction of the left ventricle: associated chromosomal anomalies

Non-compaction of the left ventricle (NCLV) is a cardiomyopathy characterized by prominent left ventricular trabeculae and deep intertrabecular recesses. Associated extracardiac anomalies occur in 14–66% of patients of different series, while chromosomal anomalieswere reported in sporadic cases. We investigated the prevalence of chromosomal imbalances in 25 syndromic patients with NCLV, using standard cytogenetic, subtelomericfluorescent in situ hybridization, and array- comparative genomic hybridization(CGH) analyses. Standard chromosome analysisdisclosed an abnormality in three (12%) patients, including a 45,X/46,XX mosaic, a 45,X/46,X,i(Y)(p11) mosaic, and a de novo Robertsonian 13;14 translocation in a child affected by hypomelanosis of Ito. Cryptic chromosome anomalieswere found in six (24%) cases, including 1p36 deletion in two patients, 7p14.3p14.1 deletion, 18p subtelomericdeletion, 22q11.2 deletion associated with velo-cardio-facial syndrome, and distal 22q11.2 deletion, each in one case. These results recommend accurate clinical evaluation of patients with NCLV, and suggest that chromosome anomaliesoccur in about one third of syndromic NCLV individuals, without metabolic/neuromuscular disorder. Array-CGH analysis should be included in the diagnostic protocol of these patients, because different submicroscopic imbalances are causally associated with this disorder and can pinpoint candidate genes for this cardiomyopathy.