Structural and molecular reorganization of cardiomyocytes in transposition of the main vessels

Studies of myocardial autopsy specimens from infants (0-12 months) with transposition of the main vessels showed the formation of a complex of compensatory adaptive, degenerative, and destructive changes, manifesting at a tissue level in cardiomyocyte heterogeneity and formation of cardiosclerosis zones. Cardiac myosin synthesis was replaced by synthesis of skeletal myosin, which was detected at the molecular level. Clinically it manifested in the progress of heart failure. Hyperplastic processes (intensive polyploid transformation of the nuclei) play an important role in heart remodeling in patients aged over 6 months. The findings of immunohistochemical and fluorescent studies seem to be prognostically important and provide more accurate data on the pathological processes in the myocardium at the initial stages of heart disease development starting from birth.