A normal ejection fraction (EF) falls between 55% and 70%. This number represents the percentage of blood your heart’s left ventricle pumps out with each beat. If your heart holds 100 milliliters of blood before a contraction, a normal heart pushes 55 to 70 milliliters into your body and retains the rest, which refills and gets pumped out on the next beat.
What Ejection Fraction Actually Measures
Your heart doesn’t empty completely with each beat, and it’s not supposed to. Ejection fraction captures how efficiently your heart’s main pumping chamber (the left ventricle) moves blood forward into circulation. It’s one of the most common numbers doctors use to assess heart function, and it often shows up on echocardiogram reports, cardiac imaging results, or post-surgical evaluations.
The right side of your heart has its own ejection fraction, which tends to run a bit lower. Studies show a normal right ventricular EF averages around 50% in men and 58% in women. But when doctors and patients talk about “ejection fraction” without specifying, they almost always mean the left ventricle.
How EF Is Measured
The most common way to measure ejection fraction is with an echocardiogram, which uses sound waves to create a real-time picture of your beating heart. It’s painless, takes about 30 to 60 minutes, and can be done in a doctor’s office or hospital. Cardiac catheterization, where a thin tube is threaded through a blood vessel to the heart, can also measure EF but is more invasive and typically reserved for situations where other heart procedures are already being performed. MRI scans of the heart provide the most precise measurement but are used less routinely because of cost and availability.
EF numbers can vary slightly between tests and even between readings on the same day. A result of 53% on one echocardiogram and 57% on another doesn’t necessarily mean your heart function changed. Small fluctuations are normal, which is why doctors look at trends over time rather than reacting to a single number.
What the Ranges Mean
Heart function is grouped into distinct categories based on ejection fraction:
- 55% to 70%: Normal. Your heart is pumping effectively.
- 40% to 54%: Mildly reduced. Your heart’s pumping ability is slightly below normal. Many people in this range have no symptoms at all, or only notice them during physical activity like climbing stairs or exercising.
- 39% or below: Reduced (heart failure with reduced ejection fraction). The lower the number, the higher the risk of serious complications. Symptoms can be significant and may affect you even at rest.
An EF above 70% can also be abnormal. It sometimes signals a condition called hypertrophic cardiomyopathy, where the heart muscle is abnormally thick and squeezes too forcefully. So higher is not always better.
It’s worth noting that some people have heart failure even with a normal ejection fraction. This is called heart failure with preserved ejection fraction, defined as an EF of 50% or higher. In these cases, the heart pumps a normal percentage of blood per beat, but the ventricle is stiff and doesn’t fill properly, so the total volume of blood moved is still too low. This is why EF alone doesn’t tell the whole story of heart health.
Does EF Change With Age or Sex?
Ejection fraction stays relatively stable across adulthood in healthy people. Unlike blood pressure or cholesterol, which tend to shift as you age, a healthy 70-year-old and a healthy 30-year-old generally have similar EF values. There is some evidence that women may have slightly higher normal values than men. A proposed revision to heart failure classifications has suggested defining “normal” as 55% or above for men and 60% or above for women, though the standard clinical cutoff of 55% for both sexes remains the most widely used.
Symptoms of a Low Ejection Fraction
People with a mildly reduced EF (40% to 54%) often feel completely fine, especially at rest. The first clue might be getting winded more easily during activities that used to feel routine, or noticing unusual fatigue after moderate exertion.
As EF drops below 40%, symptoms become more noticeable and can include shortness of breath (particularly when lying flat), swelling in the feet or abdomen from fluid retention, persistent fatigue, heart palpitations, dizziness, and nausea. At the lower end of the spectrum, these symptoms can occur even while sitting or resting. Confusion and loss of consciousness are possible with severely reduced heart function, because the brain isn’t receiving adequate blood flow.
Can Ejection Fraction Improve?
Yes, and this is one of the more encouraging aspects of this number. EF is not fixed. Depending on the underlying cause, treatment can sometimes push a reduced EF back toward the normal range.
If a blocked artery is starving part of the heart muscle, restoring blood flow through a procedure can improve pumping ability. If a heart valve is leaking or narrowed, repairing it addresses the root cause. When high blood pressure or an overactive thyroid has been straining the heart, controlling those conditions allows the heart muscle to recover over weeks to months.
Medications play a central role for people with reduced EF. Several classes of drugs work by lowering blood pressure, reducing the heart’s workload, and preventing harmful hormonal responses that worsen heart failure over time. Newer medications originally developed for blood sugar control have also shown significant benefits for heart failure patients regardless of whether they have diabetes. These treatments are most effective when started early and used consistently.
Lifestyle changes matter too. Reducing sodium intake helps prevent fluid buildup. Regular moderate exercise, guided by your care team, has been shown to improve heart function and quality of life in people with heart failure. Limiting alcohol, maintaining a healthy weight, and managing stress all contribute to better outcomes. For some people with severely reduced EF, implanted devices that help coordinate the heart’s contractions or correct dangerous rhythms can make a measurable difference.
Improvement isn’t guaranteed, and the degree of recovery depends heavily on the cause, how long the heart has been weakened, and how much damage has occurred. But many people see meaningful increases in their EF with treatment, sometimes moving from the reduced range back into mildly reduced or even normal territory.