Prevalence of isolated left ventricular (LV) diastolic dysfunction has been reported to be as high as one-third of all heart failure (HF) cases, with an increasing prevalence in the elderly population. However, there is a paucity of prospective data about the prevalence and prognosis of isolated LV diastolic dysfunction in an unselected population of patients hospitalized with HF. Therefore, we prospectively evaluated 179 consecutive patients discharged from our hospital with HF to assess the prevalence of systolic versus diastolic LV dysfunction among patients hospitalized with HF and to compare their demographics, clinical features, self-perceived quality of life (QOL), and 6-month readmission rate and mortality. Among them, 133 (59% men, median age 74 years) showed in sinus rhythm and had no significant primary valvular disease. LV diastolic dysfunction was diagnosed on the basis of the European Study Group on Diastolic HF echocardiographic criteria. QOL was assessed at hospital discharge and 6-month follow-up visit using the Minnesota Living with HF questionnaire. Survival of patients with HF was compared with that of age- and sex-matched general population. In all, 29 patients (22%) had isolated LV diastolic dysfunction and 102 (78%) had prevalent LV systolic dysfunction (ie, LV ejection fraction </= 45%). There was no difference in age, sex, or New York Heart Association functional class between patients with LV diastolic or systolic dysfunction. QOL scores were similar between the 2 patient groups with HF both at discharge (39.4 and 34) and at 6-month visit (10.4 and 10.4). Both 6-month readmission rate (48% and 48%) and median inhospital length-of-stay during readmissions (10 days and 10 days) were similar between the 2 patient groups with HF. Finally, 6-month survival, adjusted for age and sex, was similar between patients with LV diastolic or systolic dysfunction (hazard ratio 0.68; 95% confidence interval 0.20-2.35). Using standardized echocardiographic criteria, isolated LV diastolic dysfunction among unselected patients hospitalized with HF was less than previously reported. Patients with HF and isolated diastolic dysfunction showed similar clinical symptoms, self-perceived QOL, readmission rate, and 6-month mortality to patients with prevalent LV systolic dysfunction.