Abstract
Three cases of endocardial fibroelastosis, seven cases of acute nonspecific myocarditis, two cases of obscure cardiomyopathy and one autopsied case of idiopathic hypertrophic subaortic stenosis with Nielsen's syndrome were described. Development of myocardial hypertrophy along the course after the acute stage of nonspecific myocarditis in certain cases was suggested. For clarifying the possible correlation between idiopathic cardiomyopathy and nonspecific myocarditis further investigation is considered to be necessary.