Heart failure with normal systolic function. Update of prevalence, differential diagnosis, prognosis, and therapy

Our knowledge of congestive heart failure is rapidly evolving beyond the basic concept we all learned as medical students, ie, heart failure due to myocardial dysfunction can be equated to left ventricular dilatation and a poor ejection fraction. However, this "big, baggy heart" concept still dominates our clinical thinking and unfortunately disregards the 30% to 40% of patients who manifest congestive heart failure and who have normal ejection fractions.1-3Such oversights are critical in patient management, since the cause, pathophysiology, treatment, and prognosis vary significantly between those patients with heart failure who have normal, as opposed to abnormal, resting left ventricular systolic function. When confronted with a patient with congestive heart failure and a normal ejection fraction, several specific cardiac and noncardiac abnormalities should be considered.1First, it is well recognized that thesigns and symptoms of heart failure are not specificbut rather are subjective and may