Cardiomyopathy With Preexcitation and Conduction Abnormalities in a Child.

Area of Science:

• Cardiology
• Genetics
• Pediatrics

Background:

• Dilated cardiomyopathy (DCM) in children is a serious condition with various underlying causes.
• Cardiac conduction abnormalities, including fasciculoventricular pathways and sinus node dysfunction, can accompany cardiomyopathies.
• Genetic factors play a significant role in the etiology of pediatric cardiomyopathies.

Purpose of the Study:

• To report a rare case of pediatric dilated cardiomyopathy.
• To investigate the genetic basis of the cardiomyopathy and associated conduction abnormalities.
• To identify and characterize a novel genetic variant potentially contributing to the disease.

Main Methods:

• Clinical presentation of an 11-year-old boy with dilated cardiomyopathy and conduction defects.
• Whole exome sequencing (WES) to identify genetic variants.
• Computational prediction tools (Polyphen2, SIFT) to assess variant pathogenicity.
• Segregation analysis to confirm variant inheritance.

Main Results:

• The patient presented with dilated cardiomyopathy, fasciculoventricular pathway, and sinus node/atrioventricular conduction abnormalities.
• Whole exome sequencing identified a novel heterozygous variant in the LIM domain-binding protein 3 (LDB3) gene.
• Computational analyses predicted the LDB3 variant to be deleterious; segregation analysis confirmed it was inherited from the father.

Conclusions:

• A novel, potentially deleterious LDB3 gene variant is associated with dilated cardiomyopathy and complex conduction abnormalities in a pediatric patient.
• This case underscores the importance of genetic investigation in unexplained pediatric cardiomyopathies.
• The rarity of this presentation warrants further research into LDB3's role in cardiac development and disease.