[ Mutation of mtDNA and genetic background of hypertrophic cardiomyopathy]

The operation of the structural and functional units of the myocardial contractile apparatus relies on mutual myofilament movement, totally ATP dependent. As a consequence, cardiac action is integrally connected with the production of high energy ATP molecules, which are mainly synthesised in cellular mitochondrial structures. Mitochondrial dysfunction can lead to a reduced level of ATP, which is necessary to generate movement in the actino-myosin system. ATP insufficiencies may be a result of the genetic mitochondrial material (mtDNA) mutation, poorer expression of mitochondrial genes (at the transcription and/or translation stage), distorted import of proteins from the cytoplasm to the mitochondria or erroneous composition of mitochondrial breathing complexes. It has been proved that the efficacy of oxidative phosphorylation (mitochondrial ATP synthesis) is reduced with accumulated mutation of mitochondrial and/or nuclear DNA. The paper is a review of findings on the mutation of mitochondrial DNA discovered in patients with hypertrophy of the cardiac muscle. In many cases these changes accompany the mutations of the nuclear genes, but they may also be the only change discovered in the patient's genetic material.