Heart failure is defined as a clinical syndrome and is known to present with a number of different pathophysiological patterns. There is a remarkable degree of variation in measures of left ventricular systolic emptying and this has been used to categorise heart failure into two separate types: low ejection fraction (EF) heart failure or HF-REF and high EF heart failure or HF-PEF. Here we review the pathophysiology, epidemiology and management of HF-PEF and argue that sharp separation of heart failure into two forms is misguided and illogical, and the present scarcity of clinical trial evidence for effective treatment for HF-PEF is a problem of our own making; we should never have excluded patients from major trials on the basis of EF in the first place. Whilst as many heart failure patients have preserved EFs as reduced we have dramatically under-represented HF-PEF patients in trials. Only four trials have been performed in HF-PEF specifically, and another two trials that recruited both HF-PEF and HF-REF can be considered. When we consider the similarity in outcomes and neurohormonal activation between HF-REF and HF-REF, the vast corpus of trial data that we have to attest to the efficacy of various treatment (angiotensin-converting-enzyme [ACE] inhibitors, angiotensin receptor blockers [ARBs], beta-blockers and aldosterone antagonists) in HF-REF, and the much more limited number of trials of similar agents showing near statistically significant benefits in HF-PEF the time has come rethink our management of HF-PEF, and in particular our selection of patients for trials.
Keywords: HF-PEF; Heart failure; clinical trials.