The clinical profile of 19 patients with dilated cardiomyopathy ages 2-18 years (mean 13.4 +/- 4 years) was reviewed to detect any factors that might be predictive for their survival. Follow-up range from 5 to 105 months (mean 39 +/- 33 months). Routine treatment consisted of digitalis and diuretics: 14 patients received antiarrhythmics, 6 received vasodilators, and 12 were managed with immunosuppression. There were 12 survivors and 7 nonsurvivors: The 1-year mortality was 21.2% and the 2-year mortality 35.8%. All deaths were within first 2 years. Of the 12 patients who survived 2 years, a significant improvement was noticed in 9. In 3 patients tachycardia-induced cardiomyopathy was diagnosed, and abolition of supraventricular tachycardia was followed by improvement and regression of cardiomegaly. Endomyocardial biopsy was performed in 16 patients. Four with a histologic diagnosis of active myocarditis survived, and in 3 of them a considerable improvement was noticed. Of the 12 patients with nonspecific histologic findings, 6 died (p < 0.05). There were no significant differences between survivors and nonsurvivors for any of the following parameters: incidence of severe heart failure (NYHA class III-IV) and severe ventricular arrhythmias (Lown class III-V), relative heart volume, echocardiographic left ventricular diastolic diameter and shortening fraction, and the hemodynamic parameters of cardiac index, left ventricular ejection fraction, left ventricular end-diastolic pressure, and left ventricular end-diastolic volume index.