A normal ejection fraction for the left ventricle is generally 50% or higher, meaning your heart pumps out at least half the blood it holds with each beat. Some research using cardiac MRI suggests the true normal floor may be closer to 55% for men and 61% for women, but most clinical guidelines use 50% as the working cutoff.
What Ejection Fraction Actually Measures
Your heart fills with blood between beats, then squeezes to push that blood out to your body. Ejection fraction is simply the percentage of blood that gets pumped out with each squeeze. If your left ventricle holds 100 milliliters of blood and pushes out 60 milliliters, your ejection fraction is 60%.
A higher number doesn’t always mean a stronger heart. What matters is whether the percentage falls within a healthy range and whether you have symptoms. Someone with an ejection fraction of 55% and no symptoms is in a very different situation than someone at the same number with swelling, fatigue, and shortness of breath.
Normal Ranges by Sex
Women tend to have slightly higher ejection fractions than men. A large study from the Dallas Heart Study, using cardiac MRI, found a median ejection fraction of 75% in women and 70% in men. The researchers defined “low” as below 61% for women and below 55% for men. These numbers are higher than what most clinical guidelines use, partly because MRI measures the heart more precisely than other imaging methods.
In clinical practice, most doctors consider anything at or above 50% to be normal for both sexes. Some newer proposals suggest setting the normal threshold at 55% for men and 60% for women, but these haven’t been universally adopted. Age, interestingly, has very little effect on ejection fraction in healthy people. The correlation between age and EF is essentially negligible.
How Doctors Classify Low Ejection Fraction
The 2022 guidelines from the American Heart Association and American College of Cardiology break heart failure into categories based on ejection fraction:
- Preserved (50% or higher): The heart pumps normally, but other problems like stiffness can still cause heart failure symptoms.
- Mildly reduced (41% to 49%): The heart’s pumping ability is slightly below normal. This used to be called “borderline.”
- Reduced (40% or below): The heart is pumping significantly less blood than it should. This is the category most people picture when they think of heart failure.
- Improved: Previously at or below 40%, now above 40% after treatment. This category recognizes that ejection fraction can recover.
The European Association of Cardiovascular Imaging uses a slightly more detailed scale for reporting severity: normal is 56% or above, mild dysfunction is 46% to 55%, moderate is 36% to 45%, and severe is 35% or below.
Right Ventricle Has Its Own Range
Most conversations about ejection fraction focus on the left ventricle, which pumps blood to your entire body. But the right ventricle, which sends blood to the lungs, has its own ejection fraction. The average right ventricular ejection fraction is around 54%, and normal is generally considered above 51%.
Right ventricular function matters more than many people realize. Research published in Circulation: Cardiovascular Imaging found that people with a right ventricular ejection fraction below 40% had roughly three times the risk of major heart events compared to those above that threshold. Even mild right ventricular dysfunction (41% to 51%) carried a modestly increased risk.
How Ejection Fraction Is Measured
An echocardiogram is the most common test. It uses ultrasound to create a moving image of your heart, and the technician can estimate how much blood leaves the ventricle with each beat. It’s noninvasive, widely available, and usually the first test ordered.
Cardiac MRI is considered the most accurate method and is often used when echocardiogram results are unclear or when precision matters for treatment decisions. Other options include nuclear imaging scans (which track a small amount of radioactive material through your heart), CT scans, and cardiac catheterization. Your doctor picks the method based on what question they’re trying to answer and what other information they need at the same time.
Keep in mind that ejection fraction measurements can vary by 5 to 10 percentage points depending on the method used and even between different technicians. A single number isn’t always definitive, which is why doctors look at the overall picture rather than treating one measurement as absolute.
Symptoms of a Low Ejection Fraction
When the heart can’t pump enough blood to meet the body’s demands, the effects show up throughout the body. The most common symptoms include shortness of breath (especially during activity or when lying flat), swelling in the legs and feet, fatigue, and a reduced ability to exercise.
Other signs can be less obvious: a persistent cough that may produce white or pink-tinged mucus, rapid or irregular heartbeat, swelling in the abdomen, nausea, loss of appetite, and rapid weight gain from fluid buildup. In more advanced cases, the skin may take on a bluish or grayish tint from poor circulation. Some people with a mildly reduced ejection fraction have no symptoms at all and only discover the issue during routine testing.
Improving a Low Ejection Fraction
A low ejection fraction isn’t necessarily permanent. Many people see improvement with the right combination of medication, lifestyle changes, and sometimes medical devices. The American Heart Association highlights several strategies that can make a meaningful difference.
Exercise is one of the most effective tools. Working toward 20 to 30 minutes of cardio daily, even starting with simple walking, has been shown to improve ejection fraction in some patients. Strength training also helps. Cardiac rehabilitation programs offer supervised exercise plans, including home-based options, and carry unique benefits for people with heart failure.
On the lifestyle side, limiting sodium to no more than 1,500 milligrams per day, maintaining a healthy weight, quitting smoking, avoiding alcohol, and managing stress all support heart recovery. Alcohol can worsen heart failure directly, and stimulant drugs like cocaine and amphetamines are strongly linked to heart failure and should be stopped completely. Taking prescribed medications for heart failure, diabetes, or high blood pressure as directed also plays a critical role, since many of these medications directly help the heart pump more effectively over time.
For people whose ejection fraction remains severely low despite these measures, devices like cardiac resynchronization therapy can help coordinate the heart’s contractions and improve pumping efficiency. Some patients improve enough to move from the “reduced” category into the “improved” category, which the latest guidelines now formally recognize as a distinct and meaningful outcome.