Abstract
Objective. To analyze the dynamics of clinical manifestations and laboratory/instrumental parameters in 8 unrelated children with a dilated phenotype of cardiomyopathies (CMP) caused by the pathogenic variant c.602T> C in the MYH7 gene.
Material and methods. The study included 250 children with dilated phenotype CMP who were examined at the Cardiology Department of the Federal State Autonomous Institution “National Medical Research Center for Children’s Health” of the Ministry of Health of Russia. Patients underwent comprehensive clinical, laboratory and instrumental evaluation, including molecular genetic testing and cascade family screening.
Results. In 8 unrelated children with a dilated phenotype CMP and noncompact myocardium, a pathogenic nucleotide variant c.602T> C in the heterozygous state in the MYH7 gene, resulting in the amino acid variant p.Ile201Thr, was detected. A comparative analysis of the patients’ clinical data was performed, revealing specific features regarding age of onset, clinical symptoms, disease severity, and outcomes. All patients had signs of heart failure and received pathogenetic therapy. In 7 cases, normalization of cardiac chamber dimensions and contractile function was observed. In 1 case, due to inadequate adherence, the patient underwent heart transplantation.
Conclusion. Appropriate therapy combined with high patient adherence ensures a favorable clinical prognosis for carriers of genetic variant c.602T> C in the MYH7 gene. Early detection of the genetic etiology of the disease and screening of the patient’s family members facilitate timely initiation of treatment and increase the chances of a positive outcome, while systematization of clinical observations creates the foundation for developing individualized treatment approaches.
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About the authors
- Yuliya S. Burykina, Postgraduate; ORCID
- Olga P. Zharova, Cand. Med. Sci., Senior Researcher, Pediatric Cardiologist; ORCID
- Irina V. Silnova, Cand. Med. Sci., Senior Researcher, Ultrasonic Diagnostician; ORCID
- Elena N. Basargina, Dr. Med. Sci., Professor, Chief Researcher; ORCID
- Yuliya I. Davydova, Junior Researcher, Geneticist; ORCID
- Aleksandr V. Pakhomov, Researcher; ORCID
- Aleksandr A. Pushkov, Cand. Biol. Sci., Leading Researcher; ORCID
- Kirill V. Savostyanov, Dr. Biol. Sci., Head of the Medical Genetic Center, Head of Laboratory; ORCID
