[A case of acute isolated (Fiedler's) myocarditis diagnosed by histopathological study with rapid unfortunate course]

A 65 year-old-man was admitted to our hospital complaining of orthopnea and precordial oppressive feeling. Chest roentgenogram revealed congestive heart failure. Electrocardiogram revealed acute myocardial infarction-like pattern. Serum enzymes (CPK, GOT, LDH) were slightly elevated, but serum antiviral antibodies were not elevated. Echocardiogram showed severe symmetrical left ventricular (LV) hypertrophy, but there was no abnormality of LV wall motion. He died of progressive heart failure and ventricular fibrillation on the second hospital day. A necropsy was performed within one hour of death. The heart was enlarged (690 g) with both left and right ventricular hypertrophy. The myocardium disclosed a diffuse infiltration predominantly of eosinophilic leucocytes. Histopathological study revealed giant cell formation and granulomatous lesions in the myocardium. There was no overt endocarditis or pericarditis. We concluded that the severe LV hypertrophy was due to myocardial inflammatory swelling. From these findings, we diagnosed this case as acute isolated (Fielder's) myocarditis.