Very limited epidemiological data are available regarding the prognosis of heart failure and temporal changes in survival in a population-based setting in Japan. It is estimated from the total sales of digitalis, its prescription rate and usage ratio for arrhythmias that at least one million of patients suffer from heart failure in Japan. Dilated cardiomyopathy (DCM) is a major cause of severe heart failure. Over the past 27 years, three cohorts corresponding to three different periods of 9 years were investigated. Ten-year survivals were progressively improved. Patients were older and less severely affected, partly explaining the improvement in survival. In the subgroups treated with ACE inhibitors and beta blockers, calculated ten-year survival rate reached over 90%.