From the Guidelines
Yes, Heart Failure with Reduced Ejection Fraction (HFrEF) is associated with an ejection fraction of less than or equal to 40%. This classification is used to categorize patients with heart failure based on their left ventricular function. The ejection fraction represents the percentage of blood that is pumped out of the left ventricle with each contraction. In HFrEF, the heart muscle's ability to contract is significantly impaired, resulting in less blood being pumped to meet the body's needs. This reduced pumping capacity leads to the classic symptoms of heart failure including shortness of breath, fatigue, and fluid retention. Treatment for HFrEF typically includes medications such as ACE inhibitors or ARBs, beta-blockers, mineralocorticoid receptor antagonists, and more recently SGLT2 inhibitors, as noted in the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1. These medications aim to reduce the workload on the heart, improve cardiac function, and prevent further cardiac remodeling. It's worth noting that other categories of heart failure include Heart Failure with Preserved Ejection Fraction (HFpEF), where EF is ≥50%, and Heart Failure with Mildly Reduced Ejection Fraction (HFmrEF), where EF falls between 40-49%, as defined in recent guidelines and studies 1. The definition of HFrEF as an EF ≤40% is supported by multiple studies, including a systematic review and meta-analysis on pharmacotherapy for HFrEF 1. Key points to consider in the diagnosis and management of HFrEF include:
- The importance of accurate ejection fraction measurement
- The use of evidence-based medications to improve outcomes
- The consideration of other heart failure categories, such as HFpEF and HFmrEF, in the diagnosis and management of patients with heart failure.
From the FDA Drug Label
Patients with symptomatic chronic heart failure (NYHA class II–IV) and systolic dysfunction (left ventricular ejection fraction ≤ 40%) The mean left ventricular ejection fraction was 29%. LVEF ≤ 45% or fractional shortening ≤ 22.
Heart Failure with Reduced Ejection Fraction (HFrEF) is associated with an Ejection Fraction (EF) of less than or equal to 40%.
- The studies 2, 2, and 2 all define HFrEF as having a left ventricular ejection fraction of ≤ 40%.
- The mean left ventricular ejection fraction in the PARADIGM-HF trial was 29%, which is also less than 40%.
- Another trial, PANORAMA-HF, used a cutoff of LVEF ≤ 45% or fractional shortening ≤ 22, but the primary definition of HFrEF is still an EF of ≤ 40%.
From the Research
Definition of HFrEF
- Heart Failure with Reduced Ejection Fraction (HFrEF) is defined as a condition where the left ventricular ejection fraction (EF) is 40% or less 3, 4.
- This definition is supported by studies that classify HFrEF as a condition with an EF of ≤40% 5, 6.
Ejection Fraction Threshold
- The threshold for HFrEF is an EF of less than 40%, which is a key criterion for diagnosis and treatment decisions 3, 4.
- Studies have consistently used this threshold to define HFrEF and distinguish it from other forms of heart failure, such as heart failure with preserved ejection fraction (HFpEF) 5, 6.
Clinical Implications
- HFrEF is associated with significant morbidity and mortality, and its management has seen significant scientific breakthroughs in recent decades 4, 7.
- Treatment strategies for HFrEF include the use of disease-modifying drugs and device therapies, with the goal of improving symptoms, reducing hospitalization, and increasing survival 4, 7.