What is the left ventricular ejection fraction (EF) in heart failure with reduced ejection fraction (HFrEF)?

In heart failure with reduced ejection fraction (HFrEF), the left ventricular ejection fraction (EF) is defined as being less than 40%. This condition indicates a significant impairment in the heart's ability to pump blood effectively, reflecting substantial systolic dysfunction. HFrEF is characterized by a weakened myocardial contractility, which results in reduced stroke volume and overall cardiac output.

A lower ejection fraction signifies that a smaller percentage of blood is being ejected from the left ventricle with each heartbeat, which is a key diagnostic criterion for HFrEF. Understanding this range is crucial for assessing the severity of heart failure and guiding appropriate interventions and treatment strategies. Higher values, such as 50% or more, indicate a preserved ejection fraction, which is more aligned with heart failure with preserved ejection fraction (HFpEF) rather than HFrEF.