[Electron microscopical findings of the myocardium in Fallot's disease and of the ventricular septal defects (author's transl)].

Ultrastructural quantitative and qualitative investigations of the myocardium of 7 children with Fallot's disease and 3 children with a ventricular septal defect (VSD) have shown bizarre nuclei and a slight increase in the myofibril share of the volume (Fallot's disease: 51.22%; VSD: 56.85%). This may be interpreted as a sign of a cellular hypertrophy. The mitochondria have a proportion of 35.07% and 33.75%, respectively. The glycogen content is relatively high. The lipofuscin bodies originate mainly from mitochondria having a percentage of 1.43 and 1.67, respectively. Particular signs of a lesion could not be observed. From the ultrastructural findings on the morphology of heart muscle cells it can be deduced that operations of vitia may be safely carried out.