Numerous reports suggest that about one-third of patients with congestive heart failure do not have any abnormality of left ventricular systolic function. These patients presumably have heart failure on the basis of ventricular diastolic dysfunction. Our objective was to develop a comprehensive overview of published reports of the prevalence, clinical features and prognosis of diastolic heart failure and to offer recommendations for future studies. Thirty-one studies of patients with congestive heart failure with normal left ventricular systolic function were published in the time period from January 1970 through March 1995. These studies were identified with the use of computer-based searches in relevant data bases. Among patients with congestive heart failure, the prevalence of normal ventricular systolic performance in the published reports varies widely from 13% to 74%; the reported annual mortality rate also varies from 1.3% to 17.5%. The criteria for congestive heart failure, its chronicity and the age of the study sample affect the reported prevalence and prognosis of the disorder. The clinical signs and symptoms of diastolic heart failure are similar to those of patients with systolic heart failure, underscoring the need for evaluation of ventricular systolic function in patients with congestive heart failure. In the absence of any large-scale randomized clinical trial targeting these patients, the optimal treatment of diastolic heart failure is unclear. We conclude that the heterogeneity in previous studies of diastolic heart failure hinders the comparison of published reports. There is a need to conduct prospective, community-based investigations to better characterize the incidence, prevalence and natural history of diastolic heart failure. Randomized clinical trials are needed to determine optimal treatment strategies.