Case Report: Two New Cases of Autosomal-Recessive Hypertrophic Cardiomyopathy Associated With TRIM63-Compound Heterozygous Variant.

Hypertrophic cardiomyopathy (HCM) is one of the most common hereditary diseases, and it is associated with fatal complications. The clinical heterogeneity of HCM requires risk prediction models to identify patients at a high risk of adverse events. Most HCM cases are caused by mutations in genes encoding sarcomere proteins. However, HCM is associated with rare genetic variants with limited data about its clinical course and prognosis, and existing risk prediction models are not validated for such patients' cohorts. TRIM63 is one of the rare genes recently described as a cause of HCM with autosomal-recessive inheritance. Herein, we present two cases of HCM associated with TRIM63-compound heterozygous variants in young male sportsmen. They demonstrated progressively marked hypertrophy, advanced diastolic dysfunction, a significant degree of fibrosis detected by magnetic resonance imaging, and clear indications for implantable cardioverter-defibrillator. One of the cases includes the first description of TRIM63-HCM with extreme hypertrophy. The presented cases are discussed in light of molecular consequences that might underlie cardiac and muscle phenotype in patients with mutations of TRIM63, the master regulator of striated muscle mass.

Case Reports: Emery-Dreifuss Muscular Dystrophy Presenting as a Heart Rhythm Disorders in Children.

Emery-Dreifuss muscular dystrophy (EDMD) is inherited muscle dystrophy often accompanied by cardiac abnormalities in the form of supraventricular arrhythmias, conduction defects and sinus node dysfunction. Cardiac phenotype typically arises years after skeletal muscle presentation, though, could be severe and life-threatening. The defined clinical manifestation with joint contractures, progressive muscle weakness and atrophy, as well as cardiac symptoms are observed by the third decade of life. Still, clinical course and sequence of muscle and cardiac signs may be variable and depends on the genotype. Cardiac abnormalities in patients with EDMD in pediatric age are not commonly seen. Here we describe five patients with different forms of EDMD (X-linked and autosomal-dominant) caused by the mutations in EMD and LMNA genes, presented with early onset of cardiac abnormalities and no prominent skeletal muscle phenotype. The predominant forms of cardiac pathology were atrial arrhythmias and conduction disturbances that progress over time. The presented cases discussed in the light of therapeutic strategy, including radiofrequency ablation and antiarrhythmic devices implantation, and the importance of thorough neurological and genetic screening in pediatric patients presenting with complex heart rhythm disorders.