[Electronmicroscopic changes in the myocardium of children with cyanotic heart diseases]

In 7 children with Fallot's tetralogy ultrastructural quantitative and qualitative investigations on the heart muscle were carried out. Bizarre nuclei and slightly increased volume of mitochondrial part indicated hypertrophy. The amount of mitochondria was 35.07 per cent. The content of glycogen is relatively high. The lipofuscin bodies, mainly originating from mitochondria, amount to 1.43 per cent. No essential damage is observed. From the ultrastructural findings can be concluded that surgery may be done without suspicion as to cardiac cell morphology.