Keywords: heart failure, midrange ejection fraction, longitudinal, prognosis
Midrange ejection fraction (HFmrEF) is a new category of heart failure (HF), which is previously neglected. Hence, a gap of knowledge comprising the left ventricular ejection fraction (LVEF) between 40% and 49% has arisen. The previous designations of reduced or preserved ejection fraction are not necessarily static, yet few data exist to describe the natural history of LVEF over time, for HFmrEF in particular. We used multi-state Markov modelling to examine transitions among HFrEF, HFmrEF and HFpEF, and death. Initially categorized as HFmrEF patients tended to transit to HFmrEF instead of being static or to HFrEF. Women were more likely than men to transit from HFmrEF to HFpEF. Patients are less likely to transit to HFpEF from HFmrEF and those were with prior valvular heart disease or myocardial infarction were less likely to transit from HFmrEF to HFpEF. Patients with HF with midrange LVEF demonstrate a distinct clinical profile from HFpEF and HFrEF patients. However, HFmrEF is a dynamic state, which tends to transit to HFpEF and relates to gender and coexisting conditions. These findings have implications for HF patients and support potential clinical adjustment of treatment.