title: Heart diseases of unknown etiology: problems of terminology and classification.
mesh_terms: D000293:Adolescent; D000349:Africa; D009202:Cardiomyopathies; D005260:Female; D006331:Heart Diseases / Q000145:classification* / Q000209:etiology / Q000473:pathology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009206:Myocardium / Q000473:pathology; D011247:Pregnancy