A single-center study of the clinical and genetic characteristics of the dilated cardiomyopathy caused by MYH7 gene variants in eighty unrelated children

Introduction. The dilated cardiomyopathy (DCM) represents a group of myocardial disorders whose primary characteristics are dilation of the left ventricular cavity and impaired systolic function. Thanks to significant progress in the field of molecular genetics, over fifty genes responsible for the primary form of DCM have now been identified, with mutations in the MYH7 gene accounting for up to 50% of all genetically confirmed cases. Objective: to establish the clinical and genetic characteristics of the dilated cardiomyopathy caused by mutations in the MYH7 gene in children.Materials and Methods. This study analyzed data from 250 DCM children examined at the Cardiology department of the National Medical Research Center for Children’s Health of the Ministry of Health from 2015 to 2024. The investigation employed modern molecular genetic diagnostic methods and comprehensive clinical and instrumental examination, with assessment of clinical dynamics over a 5-year period.Results. Isolated MYH7-associated DCM was confirmed in 80 (40,8%) unrelated children with identified causative variants. The clinical characteristics of the disease include early onset (over 80% of cases manifesting within the first year of life), frequent combination with non-compaction of the myocardium (85%), and the development of left ventricular reverse remodeling following treatment.Variants in exons 19–23 were established to be associated with severe mitral regurgitation, requiring surgical intervention at an early age. In 3 cases, a rare combination of cardiomyopathy and myopathy was observed.Conclusion. The study confirms the significant role of pathogenic variants in the MYH7 gene in the development of cardiomyopathy in children. MYH7-associated forms of the disease with timely and appropriate drug therapy are characterized by a favorable prognosis, as evidenced by the high 5-year survival rate (97,4%) in patients. Molecular genetic testing is important in verifying the diagnosis, managing an early screening of relatives, and predicting the course of disease. The systematization of clinical and genetic characteristics creates the foundation for the devilment of personalized treatment approaches. A multidisciplinary approach to managing patients with cardiomyopathy and extracardiac manifestations is of particular importance.Compliance with ethical standards. The study was conducted in accordance with the ethical standards of the Declaration of Helsinki of 1975 and was approved by the Local Ethics Committee of the National Medical Research Center for Children’s Health of the Ministry of Health of Russia (Protocol No. 10, dated August 28, 2020). Informed consent was obtained from all participants or their legal representatives.Contribution:Burykina Yu.S. — concept and design of the study, collection and processing of material, text editing;Sdvigova N.A. — concept and design of the study, collection and processing of material, text editing;Basargina E.N. — text editing;Globa O.V. — text editing;Kurenkov A.L. — text editing;Zhanin I.S. — text editing;Pushkov A.A. — collection and processing of material, text writing;Savostyanov K.V. — concept and design of the study, text editing.All co-authors are responsible for the integrity of all parts of the manuscript and approval of its final version.Funding. The study had no sponsorship.Conflict of interest. The authors declare no conflict of interest.Acknowledgements. The authors express their gratitude to the patients’ families for supporting our research. The authors would like to express their gratitude to MD, Professor A.P. Fisenko, Director of the National Medical Research Center for Children’s Health of the Ministry of Health of the Russian Federation for his support and technical assistance in implementation of this work. The authors would like to thank the entire staff of the National Medical Research Center for Children’s Health of the Ministry of Health of the Russian Federation for the opportunity of interdisciplinary approach to patients care.Received: October 8, 2025Accepted: December 1, 2025Published: January 31, 2026