Clinical and Genetic Characteristics of Cardiomyopathy with Dilated Phenotype in 196 Russian Children: A Single-Center Study.

Background. The investigation of genetic causes underlying the dilated phenotype of cardiomyopathy (CMP) in children is of particular interest. In Russia, publications on pediatric dilated phenotype CMP are limited to isolated case reports; longitudinal studies of large cohorts integrating clinical presentation with genetic data are lacking. Aim: to describe the clinical and molecular genetic characteristics of Russian pediatric patients with dilated cardiomyopathy and analyze   correlations between disease course and identified genetic variants. Methods. Medical records of 250 children with myocardial remodeling demonstrating a dilated phenotype were analyzed. Genetic testing was performed using high-throughput sequencing for all patients, with subsequent validation of results via bidirectional Sanger sequencing. Genetic findings were correlated with patients’ clinical characteristics. Results. A genetic etiology of dilated phenotype CMP was identified in 196 patients. Over 75% of cases were attributed to sarcomeric gene variants, with mutations in thin filament genes associated with the most severe disease course. The study established clinical and genetic characteristics of CMP and identified laboratory and instrumental predictors of adverse disease outcomes. Conclusion. Early molecular genetic diagnosis in children with CMP not only enables optimized patient management, initiation of family screening, and disease outcome prediction but also lays the foundation for future development of targeted therapies.

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