Mitochondrial energy metabolism as factor of stable functioning of heart in patients with valvular heart diseases
Myocardial bioptates taken during operation from patients with valvular heart diseases were used in the study. A comprehensive investigation of mitochondrial (MCh) respiration, oxidative phosphorylation, the content of macroergs, the fluorescence of actomyosin, and the ultrastructure of organelles in the myocardial tissue was performed. It was found that the characteristics of the heart contractile activity (contractility reserves, structural and functional characteristics of actomyosin, myofibril ultrastructure) depend on MCh energy metabolism. A direct correlation between deviations in the energy status of the myocardium, clinical symptoms of the disease, and the incidence of heart failure (HF) was revealed. The hyperactivation of MCh respiration was considered as a factor of risk for the development of intraoperational complications, arrhythmia, and HF. It was proposed to enhance the metabolic defense of the myocardium against injuries through the activation of transamination (between aspartate and glutamate) as an important regulator of MCh energy and Ca<sup>2+</sup>-homeostasis.