The recent Guidelines of heart failure (HF) of the European Society of Cardiology (ESC) propose an emerging classification of HF according to left ventricular ejection fraction (LVEF) [1]. Namely, patients with LVEF between 40 and 50% are classified in an intermediate group termed HF with mid-range ejection fraction (HFmrEF). Although the authors acknowledge that this subtle distinction may account for important differences in underlying aetiologies, demographics, co-morbidities and response to therapies [2], the group, as a whole, is suggested as a mild systolic dysfunction with features of diastolic dysfunction (sic).
