Morphologic differential diagnosis of idiopathic cardiomyopathies.

Scanning electron microscopic examination of the myocardium in cardiomyopathies is a valuable complementary method beside light and transmissionelectron microscopy for the differential diagnosis of this rare disease. In two cases of congestive cardiomyopathy no marked alterations of the myocardial architecture could be found whereas in one case of nonobstructive hypertrophic cardiomyopathy myocardial cell alterations and structure disorders could be demonstrated in an almost stereologic view. The pathogenesis of heart failure in this disease was clearly shown. Similar changes were not observed in hearts without cardiomyopathy or in other forms of cardiac hypertrophy.