C16 NONCOMPACTION OF VENTRICULAR MYOCARDIUM AND X–LINKED RECESSIVE ICHTYOSIS

Abstract

Abstract Noncompact left ventricle is a rare congenital cardiomyopathy characterized by numerous ventricular trabeculae separated by deep intertrabecular recesses. It can occur in isolation or in association with neuromuscular disorders and congenital heart defects. The cause is not known but it is thought to be due to the arrest of the normal maturation process of the myocardium. Among the responsible mutations are taffazzine, ZASP and distrobrevin. It can manifest as left ventricular dilatation and dysfunction, arrhythmias, thromboembolic events, and sepsis. The echocardiogram is the investigation of first choice. Magnetic resonance allows you to more precisely distinguish compact and non–compact layers, thrombi and myocardial fibrosis. Clinical case A 19–year–old patient came for syncope. She presented with midfacial hypoplasia, cupped ears, synophrium, high palate, ichthyosis, small hands, and scarring from Achilles tendon lengthening. She denied a family history of cardiovascular disease and sudden cardiac death. Karyotype analysis showed karyotype 46Y, –X, + der t (X; Y) (p22.2; q11.1), with a chromosome derived from the X;Y translocation (a feature already known in the mother and in several maternal relatives ). Coronary angiography, electroencephalogram and brain MRI were within limits. Echocardiogram and MRI showed non–compact myocardium at the left ventricular apex and mild ventricular dysfunction with areas of anterior and posterior dyssynergia (Fig. 1). The ECG showed high QRS voltages. The Holter ECG showed numerous supraventricular extrasystoles even in pairs and runs, rare PVCs, and nocturnal pauses of up to 3 seconds. The patient underwent genetic screening by NGS for sarcomeric mutations which resulted negative. Subsequent genetic analysis showed deletion in two chromosomal regions that could be interpreted as pathogenic (chromosomal region Xp22.33 containing the SHOX gene and involving the deleted locus in Leri–Weill dyschondrosteosis and in the Xp22.33p22.31 region containing the STS gene involving the locus deleted in X–linked recessive ichthyosis) and a duplication in the chromosomal region Yq11.221q11.23 of uncertain significance. Conclusions After review of the scientific literature, the association of the illustrated complex deletion and translocation with non–compact myocardium represents a new finding, worthy of being explored in genetically affected patients.