See article by He et al. [19] (pages 72–83) in this issue . Patients with signs and symptoms of congestive heart failure (CHF) may present with a normal left ventricular (LV) ejection fraction (EF). Epidemiological studies indicate that about half of the CHF patients in the community have a relatively normal or preserved EF (typically defined as EF>50%) [1–3]. This finding appears to be in line with hospital-based studies, but the heterogeneity in patient selection, diagnostic criteria for CHF, and methods for assessment of systolic function makes it difficult to compare these studies [4]. Compared to patients with CHF and depressed EF, patients with CHF and preserved EF are older, are more often women, more frequently have a history of hypertension, and less frequently have coronary artery disease [1–4]. CHF is the most frequent cause of hospitalization in persons 65 years of age or older, and a recent large-scale, population-based study [5] indicates a prevalence for CHF of 4.9% in this age group. Interestingly, only 22% of these CHF patients had overtly impaired LV systolic function (defined as EF<45%). Of note is that the mean age of patients represented in the major CHF treatment trials is typically 59–65, whereas the mean age of patients in the community at the time of first diagnosis of CHF appears to be about 77 [1,6]. It is often assumed that the prognosis of CHF patients is better for those with a preserved EF. This notion is supported by the meta-analysis by Vasan et al. [4] which covers 31 studies on CHF with preserved EF performed between 1970 and 1995. The reported annual mortality rate in the reviewed studies ranged between 1.3% and 17.5%. This wide range is partly related to variation in the patient selection criteria and … *Corresponding author. Tel.: +31 71 526 2020; fax: +31 71 526 6809. E-mail address: p.steendijk{at}lumc.nl