In every dispensary or hospital for the treatment of diseases of children, and also to almost the same extent in private practice, there are seen many cases of organic heart disease in later childhood where only few facts bearing directly on the etiology can be found. In adults the case is different, because in them many of the organic valvular defects and many of the murmurs produced by degenerative changes in the myocardium are due to wear and tear necessitated by the conditions of life. In adults also disease of the heart secondary to lesions in other organs—notably the kidneys—and to errors in metabolism is encountered more frequently than in the case of children. In childhood these factors donot enter except in occasional instances, and the occurrence of endocarditis or of myocardial changes giving rise to cardiac signs and symptoms must in them be attributed to the occurrence of infection.
PACKARD FA. THE ANTECEDENTS OF ORGANIC HEART DISEASE IN CHILDREN.. JAMA. 1900;XXXV(25):1614-1618. doi:10.1001/jama.1900.24620510022001f