A retrospective analysis of the statistical data of persons who died in the Tambov region over the past 5 years revealed one case of death from non-compact cardiomyopathy. The incidence of non-compact cardiomyopathy in the population is 0.014 to 1.3 %. Due to the non-proliferation of this pathology, a single recorded case attracted attention for research. This study presents a 10-year-old patient who was admitted to the intensive care unit in the decompensation stage, during which the disease ended in death. After analyzing the medical documentation, it was found that with the development of the disease, the clinical picture was erased, symptoms from the cardiovascular system did not appear, signs of decompensation were not observed until the moment of this hospitalization. Death occurred suddenly, autopsy revealed non-compact cardiomyopathy of the left ventricle, which through its complications led to non-coronary ischemia of the subepicardial myocardium of the left ventricle, which was the cause of death. Since the pathology is quite rare, the purpose of our study is to consider, on the example of a clinical case, the factors contributing to the fatal outcome in non-compact cardiomyopathy.