Understanding how well your heart pumps blood is essential for monitoring your overall cardiovascular health and guiding important treatment decisions.
What is Ejection Fraction?
Ejection fraction is a measurement that tells doctors how effectively your heart is pumping blood with each beat. It represents the percentage of blood that leaves your heart’s lower chambers, called ventricles, every time your heart contracts. Think of it this way: if your heart fills with blood and then squeezes to push that blood out to your body, the ejection fraction shows what portion actually gets pumped out during that squeeze.[1]
Your heart has four chambers that work together like a coordinated pump. The two upper chambers, called atria, receive blood from your veins and lungs. The two lower chambers, the ventricles, do the heavy lifting by pumping blood out to your body. Between heartbeats, there’s a brief pause when blood flows from the atria down through valves into the ventricles. Once a ventricle fills up, the next heartbeat pumps out a portion of that blood to where it needs to go.[1]
Most often, doctors measure the left ventricular ejection fraction, or LVEF, because the left ventricle is your heart’s main pumping chamber. This powerful chamber sends oxygen-rich blood through your body’s main artery, the aorta, and then out to all your organs and tissues. The right ventricle also has an ejection fraction, but it’s measured less frequently since it pumps blood to your lungs to pick up oxygen, and right-sided heart problems are less common than left-sided ones.[1][3]
How Normal Ejection Fraction is Measured
Doctors use several different imaging techniques to measure your ejection fraction accurately. The most common method is an echocardiogram, which uses sound waves to create pictures of your beating heart. A technologist places a handheld device on your chest, and ultrasound waves bounce off your heart structures to create images. Three-dimensional images tend to provide the most accurate readings.[5][6]
Another option is a cardiac MRI, where you lie on a bed that slides into a large magnetic tube. This test uses a magnetic field, radio waves, and a computer to create detailed images of the inside of your heart. Some doctors may use a nuclear stress test or multigated acquisition scan (MUGA), which involves injecting a small amount of radioactive dye into your vein. As this dye moves through your heart, a camera captures images of your heartbeats.[5][6]
In some cases, doctors perform cardiac catheterization, where a hollow tube is inserted into a large blood vessel to monitor your heart function directly. During this procedure, a dye is often injected, and X-rays track how blood flows through your heart. Each of these tests has its own advantages, and your doctor will choose the one that best fits your specific situation.[6]
Understanding Normal Ejection Fraction Range
In a healthy heart, the ejection fraction typically falls between 50% and 70%. This means that with each heartbeat, your heart pumps out 50% to 70% of the blood sitting in your left ventricle. Even a healthy heart doesn’t pump out all the blood in the ventricle with each beat—some always stays behind. This is completely normal and expected.[1][3]
There are slight differences in what’s considered normal based on your sex. For males, a normal range is typically 52% to 72%, while for females it’s 54% to 74%. According to the American Heart Association, a left ventricle ejection fraction of about 50% to 70% is categorized as normal. Values slightly below this range might still support relatively normal heart function, but they warrant closer monitoring.[1][3][6]
When your ejection fraction falls between 41% and 49%, it’s considered mildly reduced. This is sometimes called a mid-range ejection fraction. If your number drops to 40% or below, it’s classified as reduced, and this typically indicates that your heart muscle is weakened and struggling to pump enough blood to meet your body’s needs. An ejection fraction of 30% or below is considered severely abnormal and indicates significant heart problems.[1][4]
The Formula Behind Ejection Fraction
The ejection fraction calculation is actually quite straightforward mathematically. It’s determined by dividing the volume of blood pumped out of your ventricle with each heartbeat—called the stroke volume (SV)—by the total amount of blood in the ventricle before it contracts, known as the end-diastolic volume (EDV). This result is then multiplied by 100 to express it as a percentage. The formula looks like this: EF = (SV/EDV) × 100.[1][5]
In simpler terms, ejection fraction tells you what percentage of the blood in your ventricle gets pushed out to your body with each heartbeat. If your heart holds 100 milliliters of blood and pumps out 60 milliliters with each beat, your ejection fraction would be 60%. The imaging tests mentioned earlier help doctors measure these volumes accurately so they can calculate this important percentage.[5]
Why Ejection Fraction Matters
Your ejection fraction is one of the most important indicators of how well your heart is working. It serves as a key marker of your heart muscle’s strength and ability to contract. Medical professionals recognize it as one of the strongest predictors of cardiovascular outcomes across all ages and genders. This single measurement can influence many important decisions about your care.[1][7]
Doctors use ejection fraction to diagnose heart failure, which doesn’t mean your heart has stopped—it means your heart can’t pump as much blood as your body needs. A low ejection fraction typically indicates you have heart failure or are at risk for developing it. This measurement also helps doctors decide which medications might work best for you, whether you might need special devices like pacemakers or defibrillators, and how to monitor your condition over time.[1][5][7]
The measurement is crucial for risk assessment as well. If your ejection fraction is 35% or below, you’re at higher risk of developing dangerous irregular heart rhythms called arrhythmias, or even heart failure. These numbers help your care team determine whether you might benefit from preventive treatments or closer monitoring.[12]
Heart Failure with Preserved Ejection Fraction
Not everyone with heart failure has a low ejection fraction. Some people develop a condition called heart failure with preserved ejection fraction (HFpEF), sometimes referred to as diastolic heart failure. In this situation, your ejection fraction might be completely normal—above 50%—but you still experience symptoms of heart failure.[1][4]
What happens in HFpEF is that your heart muscle becomes thick or stiff. Even though each contraction pumps out a normal percentage of the blood, the ventricle holds less blood than it should because the stiff tissue has effectively shrunk its capacity. When this happens, your heart can’t deliver enough oxygen-rich blood to meet your body’s needs, even though it’s pumping efficiently. The amount just isn’t enough.[1][5]
Several conditions can put you at risk for HFpEF. High blood pressure is one of the most common causes, along with diabetes, irregular heartbeat, heart valve problems, obesity, kidney disease, and chronic obstructive pulmonary disease (COPD). Coronary artery disease, cardiac tamponade (fluid around the heart), and heart valve disease can also lead to this condition. It’s more common among elderly people and women.[1][5][10]
What Causes Abnormal Ejection Fraction
When your ejection fraction falls outside the normal range, it often signals an underlying heart condition. Many different problems can weaken your heart muscle over time. Cardiomyopathy, a disease of the heart muscle itself, can make your heart muscle become enlarged, thick, or stiff. This condition has various causes, including viral infections or genetic disorders passed down in families.[12][16]
A heart attack is another major cause of reduced ejection fraction. When blood flow to part of your heart muscle gets blocked, that tissue can be damaged permanently, weakening your heart’s overall pumping ability. Coronary artery disease, where arteries supplying blood to your heart become narrowed, can also reduce ejection fraction over time.[12][16]
Heart valve disease affects ejection fraction as well. When one or more of your heart valves don’t open and close properly, it puts extra strain on your heart. Chronic high blood pressure forces your heart to work harder over many years, which can eventually decrease ejection fraction. An abnormally fast heart rate sustained over a long period—such as from uncontrolled atrial fibrillation—can also weaken the heart gradually.[12][16]
Symptoms That May Accompany Abnormal Ejection Fraction
When your ejection fraction drops below normal, your body may not be getting enough oxygen-rich blood, and you might experience various symptoms. Fatigue is one of the most common complaints—you may feel unusually tired even with normal activities. Many people notice shortness of breath, especially during physical activity or when lying flat. This happens because blood that isn’t efficiently pumped out can back up into your lungs.[12]
Swelling, or edema, is another frequent symptom. You might notice your legs, ankles, or feet becoming puffy and swollen. Some people also experience swelling in their abdomen, which can cause a feeling of fullness or bloating. This fluid buildup occurs because your weakened heart can’t effectively move blood through your circulatory system.[4][12]
Other symptoms can include heart palpitations—a fluttering sensation in your chest—a rapid heartbeat, loss of appetite, or nausea. Some people find their ability to exercise becomes significantly reduced. If you’re experiencing two or more of these symptoms, especially if you already know you have a heart condition, it’s important to see your doctor right away.[12]
Improving and Managing Your Ejection Fraction
The good news is that ejection fraction isn’t necessarily fixed—in many cases, it can improve or at least be stabilized with proper treatment. Lifestyle changes play a significant role in managing heart health. Regular physical activity can help strengthen your heart over time. Both aerobic exercise and strength training are beneficial. Larger, more efficient muscles in your legs and arms can better extract oxygen from your blood, which helps compensate for your heart’s reduced pumping power. However, if you’re not already exercising regularly, check with your doctor before starting any new exercise program.[16][20]
Making changes to your diet can also make a difference. Reducing salt intake helps prevent fluid buildup. Some doctors recommend monitoring how much fluid you drink throughout the day. Maintaining a healthy weight reduces the workload on your heart. If you smoke, quitting is one of the best things you can do for your heart health. Limiting alcohol consumption is also advisable—if your heart failure is related to alcohol use, you may be advised to stop drinking entirely.[12][19]
Many medications can improve or stabilize ejection fraction. Beta blockers, ACE inhibitors (angiotensin-converting enzyme inhibitors), and angiotensin-receptor blockers (ARBs) are commonly prescribed. Doctors increasingly try to get patients with reduced ejection fraction on what’s known as the “four pillars” of therapy—drugs from four different classes that help in different ways. Diuretics may be prescribed to help your body get rid of excess fluids. Aldosterone antagonists are another class of medication that can be helpful.[12][16][20]
For some people, medical devices offer additional help. A biventricular pacemaker can help your heart chambers pump blood more effectively and in better coordination. An implantable cardiac defibrillator (ICD) sends small electrical pulses to your heart to restore a healthy rhythm if dangerous arrhythmias develop. In severe cases where other treatments aren’t working, a heart transplant might be considered.[12][24]
Living with Changes in Ejection Fraction
If you’ve been diagnosed with an abnormal ejection fraction, regular monitoring becomes an important part of your care. You’ll likely have appointments with your doctor or care team at least every six months. These visits give you a chance to discuss how you’re feeling, whether your symptoms are getting better or worse, and whether your medications are working well or causing side effects.[19]
Your care team may ask you to help monitor your condition between appointments. For example, you might be asked to weigh yourself regularly at home. Changes in your weight can be an early sign of fluid buildup and might indicate that your condition needs attention. If your symptoms worsen or you develop new ones, contact your care team right away rather than waiting for your next scheduled appointment.[19]
Having heart failure or an abnormal ejection fraction doesn’t necessarily mean you can’t travel or go on vacation, as long as you feel well enough and your condition is stable. However, it’s wise to check with your doctor before making travel plans. Traveling to high altitudes or hot, humid places might put extra strain on your heart. If you’re flying, inform the airline of your condition—they may be able to provide a wheelchair to help you avoid long walks through the airport. Always carry your medications in two different places when traveling in case one gets lost, and keep a list of what you’re taking and why.[19]
Prognosis and Outlook
Life expectancy with heart failure and reduced ejection fraction has improved significantly over time, thanks to better medications and treatments. How long someone can live with these conditions depends on many factors, including age at diagnosis, the strength of heart function, the presence of other health conditions, and how well treatment works.[22]
People under age 65 generally have better outcomes than those diagnosed at older ages. The amount of blood your heart pumps out—your ejection fraction—affects prognosis as well, though outcomes have improved across all ranges with modern treatment. Those with an ejection fraction of 35% or below face higher risks, but many treatments can help manage these risks effectively.[22]
An ejection fraction between 40% and 50% is considered borderline and may signal future heart failure risk, but early intervention can make a real difference. Many people with proper treatment and lifestyle changes can maintain a good quality of life and continue their normal activities. Understanding your condition and working closely with your healthcare team gives you the best chance for a positive outcome.[16][20]
