Heart failure with mildly reduced ejection fraction (HFmrEF) has often been described as the "forgotten" heart failure phenotype. Falling between heart failure with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF), these patients frequently occupy a diagnostic and therapeutic gray zone.

In the June episode of Heart Failure Beat, hosts Michael Beasley, MD, and Priya Umapathi, MD, spoke with Jane E. Wilcox, MD, and Barry A. Borlaug, MD, co-lead authors of the newly published HFSA Scientific Statement: Heart Failure with Mildly Reduced Ejection Fraction, published in the June 2026 issue of the Journal of Cardiac Failure. 

Dr. Wilcox described HFmrEF as "an incredibly common diagnosis that you've never heard of," noting that the condition affects approximately 10–25% of patients with heart failure. 

HFmrEF – Not a Static Diagnosis

One of the central themes of the discussion was that HFmrEF should not be viewed as a static diagnosis. Instead, the Scientific Statement frames HFmrEF as both an overlap state and a transitional state. Patients may share characteristics of both HFrEF and HFpEF, and many move between categories over time. 

"We really felt that patients still needed to be treated, they still needed to be evaluated," Dr. Wilcox explained when discussing the motivation behind the statement. "It's for the patients and those who take care of the patients." 

Practical Management of HFmrEF

The conversation also addressed practical management. While randomized trial evidence specific to HFmrEF remains limited, both authors emphasized that clinicians should not dismiss patients simply because they fall into this intermediate ejection fraction range. Dr. Borlaug noted that HFmrEF often resembles HFrEF more closely than HFpEF and argued that clinicians should take the diagnosis seriously and consider foundational heart failure therapies when appropriate. 

Future Research Priorities

The episode concludes with a discussion of remaining knowledge gaps and future research priorities, including better methods for identifying which HFmrEF patients are more biologically aligned with HFrEF versus HFpEF and the need for broader inclusion of these patients in future clinical trials. 

For clinicians caring for patients with heart failure, the new HFSA Scientific Statement offers practical guidance and an important reminder: HFmrEF is not simply a midpoint on an ejection fraction scale—it is a meaningful clinical population deserving of thoughtful evaluation and treatment.

Read the HFSA Scientific Statement.

🎧 Listen now to this episode.

Disclaimer:

The opinions and perspectives expressed in this episode are those of the individual guests and hosts and do not necessarily reflect the official views of the Heart Failure Society of America (HFSA). This discussion is intended for educational purposes only and does not constitute medical advice or an endorsement of any specific pharmaceutical product or therapy. HFSA does not endorse one medication over another. Patients should consult their healthcare professionals for individualized evaluation and treatment decisions.