Heart Failure With Improved Ejection Fraction: Definitions, Epidemiology, and Management.

Heart failure with improved ejection fraction (HFimpEF) has gained increasing recognition as a distinct phenotype within the spectrum of heart failure, characterized by previously reduced left ventricular ejection fraction (≤40%) that subsequently improves to >40%. HFimpEF remains relatively understudied, and uncertainty persists regarding its long-term prognosis and optimal management. Contemporary registries and clinical trials suggest a rising prevalence, likely reflecting both the increased implementation of guideline-directed medical therapy and evolving consensus definitions for its identification. Despite left ventricular ejection fraction recovery, patients with HFimpEF remain at risk for adverse outcomes, and their management remains an area of active investigation. The aim of this review is to provide an in-depth evaluation of HFimpEF, including its epidemiology, pathophysiology, prognosis, and treatment strategies. The authors also highlight existing clinical gaps and propose future research directions to refine risk stratification and therapeutic approaches for this evolving population.