Twenty three patients with Coxsackie-B viral myocarditis (16 patients), perimyocarditis (3 patients) or pericarditis (4 patients) were reviewed with respect to their clinical features and the long-term prognosis. All except two patients presented Coxsackie-B viral infection with at least a four fold rise or fall of the neutralizing antibody titer in the paired sera, the other two were autopsy patients showing a pathological evidence of myocarditis and a significant elevation in the titer in the single measurement. Antecedent symp-toms, cardiac manifestations and electrocardiographic findings were closely compatible to others described in previous reports. In the analysis of serum enzyme in the acute stage, the majority of patients with myocarditis developed a moderate-to-marked elevation of GOT and CK, while patients with pericar-ditis did not. Thus abnormal enzyme pattern seemed to be an important sign of myocardial damage. In addition, GPT and LDH (dominant in LDH5) were elevated in most patients with myocarditis, suggesting liver involvement. As patients with myocarditis sometimes develop abnormal Q associated with chest pain, the abnormal enzyme pattern would be a valuable clue in differentiating from myocardial infarction. Another interesting findings was a lack of eleva-tion of erythrocyte sedimentation rate, observed in 7 patients. A possible ex -planation for this is an association of disseminated intravascular coagulation. The lack of elevation appeared to be a sign of poor prognosis. In the long-term follow-up of those patients who had recovered almost completely by the time of discharge, none developed a recurrence of myocarditis or any cardiac manifestation of residual myocardial damage. Thus, patients with acute myo-carditis appeared to rarely progress to dilated cardiomyopathy if they had re-covered completely from the acute stage.