[Eosinophilic heart disease with favorable courses: report of two cases].

Two cases of eosinophilia-associated acute peri-myocarditis which coursed favorably are reported. Case 1 was a 47-year-old man whose ECG revealed QS, ST-T change, bundle branch block, and arrhythmias. Case 2 was a 30-year-old man whose ECG showed ST segment depression. The chest radiographs of both patients revealed enlarged hearts. Left ventriculography showed abnormal regional wall motion. Their endomyocardial biopsies revealed eosinophilic infiltration of the myocardium, but few eosinophils were degranulated. In Case 1, the development of eosinophilia preceded perimyocarditis and the eosinophilia continued even after the symptoms of peri-myocarditis were improved. In conclusion, it seems that eosinophilia did not have specific relation to the initial manifestation of the disease but that it occurred as a secondary reaction to peri-myocarditis of unknown etiology in these cases.