Features of a clinical course and an outcome of inherited cardiomyopathies in association with a myocarditis in children

Myocardial diseases take a significant place in the world of the modern science and practical medicine, which is confirmed by a large number of publications. Despite the fact that the problems of myocarditis and cardiomyopathies have been studied for many years, there are still gaps in the diagnosis and management of these conditions, especially in cases of their co-existence. The mechanisms of mutual influence of these nosologies are also insufficiently studied. In particular that clinical situation in young patients is a specific problem. Objective. To evaluate the features of the clinical course and outcome of genetically determined cardiomyopathies in association with myocarditis in children. Materials and methods. The study is retrospective. The case histories of 17 pediatric patients with severe cardiomyopathies with the development of terminal heart failure were analyzed. 8 (47.0%) patients (3 boys and 5 girls) had a combination of genetically determined cardiomyopathy and confirmed myocarditis. All patients underwent an assessment of their medical history, laboratory parameters and results of instrumental examination methods. Results. 7 (87.5%) patients out of 8 children with a combination of cardiomyopathy and myocarditis underwent orthotopic heart transplantation on average 7 years after the onset of the first symptoms of the disease. Of these, 2 (28.5%) children had auxiliary blood circulation systems installed as a “bridge to the heart transplantation” — LVAD in one case and ECMO with subsequent implantation of the Excor system in the other case. In one case, there was a fatal outcome (12.5%) due to the development of a refractory polymorphic ventricular tachycardia. Conclusion. This work demonstrates the need for additional vigilance and more active actions in relation to the management of patients with atypical, severe myocarditis, as well as in the case of rapid progression of genetically determined cardiomyopathy.