The relationship of idiopathic cardiac hypertrophy to foetal endocarditis.

Idiopathic cardiac hypertrophy in children may be divided into those cases associated with glycogen infiltration, and those without. A characteristic feature of the latter is the presence of gross fibroelastic thickening of the endocardium (Kugel and Stoloff, 1933; Mahon, 1936). This thickened endocardium, frequently associated with myocardial scarring, has suggested that an inflammatory basis underlies the condition. Gross (1941), however, in a review of so-called foetal endocarditis, has brought convincing evidence against this concept, and attributes the myocardial changes to impaired nutrition secondary to the endocardial thickening. The case presented here suggests that endocardial fibro-elastosis, which is found in 70% of cases of so-called foetal endocarditis (Gross, 1941) may, in cases surviving the neonatal period, lead to the condition of idiopathic cardiac hypertrophy in children, the myocardial hyperplasia being secondary to the endocardial thickening.