Diastolic heart failure or heart failure with a normal ejection fraction

Nearly half of patients with symptoms of heart failure are found to have an left ventricular (LV) ejection fraction which is within normal limits. These patients have variously been labeled as having diastolic heart failure, heart failure with preserved LV function or heart failure with normal ejection fraction (HFNEF). Since recent studies have shown that systolic function is not entirely normal in these patients, HFNEF is the better term. More common in elderly females it has a mortality similar to heart failure with a reduced ejection fraction (HFREF). The exact pathophysiology of the symtpoms is still not clear and, therefore, debated. As heart failure is often episodic, the underlying abnormal mechanisms may not be completely apparent at rest. It is likely there is a mixture of systolic and diastolic dysfunction which will be different to some degree in individual patients and isolated diastolic dysfunction or primary abnormalities of relaxation are probably extremely rare. The main difference between HFNEF and HFREF is the degree of ventricular remodeling with increased ventricular volumes in HFREF. The time course of remodeling depends to some extent on the aetiology being quicker post myocardial infarction--the commonest cause of HFREF, and slower with hypertension which is the most frequent aetiological factor in HFNEF. Ventricular volumes rather than ejection fraction or the concept of a pure diastolic abnormality can be used to classify patients in a more rational manner.