Introduction Heart failure (HF) has been classically divided into HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). However, to better classify HF patients with a left ventricular ejection fraction (LVEF) between 41 and 49%, previous guidelines have introduced the term HF with mid-range ejection fraction. Nonetheless, shortly after its formal introduction, HF with mid-range ejection fraction is now called HF with mildly reduced ejection fraction (HFmrEF). In this letter, we explore the reasons behind this […]