Types of Heart Failure Explained: HFrEF, HFpEF, and HFmrEF

Heart failure is grouped into types mainly by how well the left ventricle pumps blood. This is measured by ejection fraction. HFrEF occurs when the heart squeezes weakly, with ejection fraction of 40 percent or less. HFpEF happens when the heart muscle is stiff and does not fill properly, with ejection fraction of 50 percent or higher. HFmrEF falls in between, with ejection fraction from 41 to 49 percent. These groups help doctors understand the underlying problem. Only a healthcare professional can determine the type after full evaluation.

Heart failure does not mean the heart has stopped working. It means the heart cannot pump blood as effectively as the body needs. Doctors often classify it by the left ventricular ejection fraction, or the percentage of blood pushed out of the main pumping chamber with each beat. A normal ejection fraction is generally around 55 to 60 percent, though values can vary. Classification based on this measurement guides understanding of the condition and supports personalized care planning.

According to the American Heart Association, the three main categories by ejection fraction are heart failure with reduced ejection fraction (HFrEF), heart failure with preserved ejection fraction (HFpEF), and heart failure with mildly reduced ejection fraction (HFmrEF). These labels describe different ways the heart may struggle, even when symptoms such as shortness of breath or fatigue appear similar.

What ejection fraction tells us about the heart

Ejection fraction is measured most often during an echocardiogram, a painless ultrasound of the heart. It shows how much blood leaves the left ventricle each time it contracts. When the number is lower than expected for a person’s situation, or when the heart muscle does not relax well between beats, doctors look more closely at the overall picture. This includes symptoms, medical history, physical exam findings, and other test results. A single measurement is never interpreted in isolation.

Changes over time also matter. An ejection fraction that differs from previous results may prompt further assessment. Personal baseline values and trends help healthcare professionals decide next steps. Only a licensed clinician can interpret these findings within the full clinical context.

Heart failure with reduced ejection fraction (HFrEF)

In HFrEF the left ventricle does not contract forcefully enough. As a result, less blood is pumped out to the body with each heartbeat. This is sometimes called systolic heart failure. The ejection fraction is typically 40 percent or lower. The heart muscle may become stretched or weakened over time.

Common underlying issues linked to this pattern include damage from a prior heart attack, long-standing coronary artery disease, or certain cardiomyopathies. High blood pressure that has been present for years can also contribute by overworking the heart muscle. People with HFrEF may notice fluid buildup in the lungs or legs, though experiences differ widely. Related information on how fluid retention develops appears in discussions of heart failure and swelling.

The Mayo Clinic notes that HFrEF is a form of left-sided heart failure in which the ventricle cannot squeeze as strongly as it should. Management decisions are always individualized and based on the complete clinical assessment rather than the ejection fraction number alone.

Heart failure with preserved ejection fraction (HFpEF)

In HFpEF the heart muscle is stiff or thickened. It does not relax properly between beats, so the ventricle cannot fill with enough blood. Even though the pumping percentage (ejection fraction of 50 percent or higher) looks relatively normal, the total amount of blood moved may still fall short of the body’s needs. This pattern is sometimes called diastolic heart failure.

HFpEF is frequently associated with aging, long-term high blood pressure, obesity, diabetes, or other conditions that affect the heart’s ability to relax. Women and older adults appear more often in this group. Symptoms such as breathlessness with activity or fatigue can still occur because the heart cannot increase its output effectively during physical effort. Readers seeking more detail on breathing difficulties can explore heart failure and shortness of breath.

According to the Cleveland Clinic, the ventricles in HFpEF are stiff and cannot relax enough to fill fully, so less blood is available for each contraction even when the ejection fraction remains in the higher range.

Heart failure with mildly reduced ejection fraction (HFmrEF)

HFmrEF sits between the other two categories. The ejection fraction measures between 41 and 49 percent. Some people in this range show features that resemble HFrEF, while others share characteristics more common in HFpEF. The heart may have a mild reduction in pumping strength along with some filling challenges.

This category has received greater attention in recent years because it helps clinicians recognize patients who previously fell into a less clearly defined zone. Ejection fraction can change over months or years, so someone initially classified here may later move into another group. Repeat imaging and clinical follow-up are therefore important. The British Heart Foundation explains that heart failure may be classed as HFmrEF when the percentage falls in this middle range, alongside other test findings.

Understanding how the left and right sides of the heart interact also adds useful context. Left-sided problems often lead to right-sided involvement over time. Further explanation of these patterns is available in the overview of left-sided versus right-sided heart failure.

Key differences at a glance

The table below summarizes the main features that distinguish the three types. It is intended only as a general reference. Actual classification always depends on the full evaluation by a healthcare professional, including symptoms, history, and additional tests beyond the ejection fraction number alone.

Feature HFrEF HFmrEF HFpEF
Typical ejection fraction 40% or lower 41% to 49% 50% or higher
Main pumping issue Weak contraction (systolic) Mildly reduced contraction Impaired filling or relaxation (diastolic)
Common associations Prior heart attack, weakened muscle Features of both reduced and preserved patterns Stiff or thickened muscle, aging, hypertension
How it is confirmed Echocardiogram plus clinical findings Echocardiogram plus clinical findings Echocardiogram plus clinical findings and evidence of elevated filling pressures

These distinctions help organize care but do not replace a thorough medical assessment. Trends in ejection fraction, response to previous treatments, and coexisting conditions all influence how a doctor approaches each individual situation. Additional background on the overall condition is found in the main heart failure overview.

Classification by ejection fraction is a practical tool, yet heart failure remains a clinical syndrome. Symptoms, physical signs, blood tests such as natriuretic peptides, and imaging findings must all be considered together. An ejection fraction value is a finding that requires professional interpretation within the broader picture of a person’s health.

Shared symptoms and contributing factors

Many people experience overlapping symptoms regardless of the specific type. Shortness of breath, especially with activity or when lying flat, fatigue, and swelling in the legs or abdomen are frequently reported. These signs occur because the heart cannot keep up with the body’s demand for oxygen-rich blood or because fluid backs up in the lungs or tissues. A full discussion of possible manifestations appears under symptoms of heart failure.

Contributing factors often include coronary artery disease, high blood pressure, diabetes, obesity, heart valve problems, or prior damage to the heart muscle. Lifestyle elements such as smoking, heavy alcohol use, and limited physical activity may also play a role. Genetic factors and certain infections can contribute in some cases. Detailed information on underlying reasons is available in the section on causes of heart failure.

  • Long-term high blood pressure that overworks the heart
  • Narrowed coronary arteries or previous heart attack
  • Diabetes and related metabolic changes
  • Obesity and associated inflammation
  • Heart valve disorders that increase workload
  • Certain viral infections or toxic exposures

Congestive features, in which fluid accumulates in the lungs or body tissues, can occur with any of the three types. More on this pattern is covered under congestive heart failure.

How doctors evaluate and classify the condition

Evaluation typically begins with a careful history and physical examination. An echocardiogram provides the ejection fraction and shows the size and motion of the heart chambers. Blood tests that measure natriuretic peptides may support the clinical impression. Other tests such as electrocardiograms, chest X-rays, or stress studies may be ordered depending on the individual situation. The process is described further in material on heart failure diagnosis.

Classification is not static. Ejection fraction can improve, remain stable, or decline depending on the underlying cause, response to care, and other health factors. Someone with HFmrEF may later be reclassified, which is why ongoing monitoring is valuable. Treatment approaches differ in emphasis across the categories, and decisions are always made by the clinical team after reviewing the complete picture. General information on available approaches can be found under heart failure treatment.

When medical evaluation is recommended

Anyone experiencing new or worsening shortness of breath, unexplained fatigue, swelling in the legs or abdomen, or sudden weight gain should contact a healthcare professional promptly. These symptoms do not automatically mean heart failure is present, but they warrant assessment so that appropriate testing and guidance can be provided. People already living with heart failure benefit from regular follow-up so that any change in symptoms or test results can be addressed early.

Seeking care does not mean a diagnosis will automatically follow. Many conditions can produce similar feelings of breathlessness or tiredness. A thorough evaluation helps distinguish among possibilities and ensures that any findings are interpreted correctly in light of the person’s overall health.

Living with any form of heart failure involves partnership with the care team, attention to daily habits that support heart health, and open communication about symptoms. Educational resources on daily management appear in discussions of living with heart failure.

Understanding the distinctions among HFrEF, HFpEF, and HFmrEF can help patients and families ask informed questions during medical visits. The goal of classification is not to create rigid categories but to support clearer communication and more tailored care plans. Every person’s experience is unique, and professional guidance remains essential for interpretation and decision-making.