What Is Ejection Fraction?

Ejection fraction (EF) measures the amount of blood pumped out of your heart’s lower chambers, or ventricles. It’s the percentage of blood that leaves your left ventricle when your heart contracts.

Measuring your ejection fraction can help doctors figure out whether you have certain heart problems, especially one type of heart failure. Despite the scary-sounding name, heart failure doesn’t mean your heart stops, it just means it can’t pump as much blood as your body needs. Your ejection fraction will also help the doctor decide which treatments are best for you and whether your treatment is working.

How Is Ejection Fraction Measured?

There are a few ways your doctor can find out your EF percentage. You’ll probably have one of these tests:

• Echocardiogram, or “echo.” A technologist puts a hand-held wand on your chest. It uses ultrasound waves to take pictures of your heart.
• MRI. You lie on a bed that slides into a large magnetic tube. MRI uses a magnet, radio waves, and a computer to create pictures of the inside of your body, in this case your heart.
• Nuclear stress test or multigated acquisition scan (MUGA). Your doctor injects a small amount of radioactive dye into your vein. As it moves through your heart, a camera makes images of your heartbeats

What Is a Normal Ejection Fraction?

Many doctors consider a normal ejection fraction to be 55% to 75%. If yours is 50% or lower, it’s a sign that your heart — usually your left ventricle — may not pump out enough blood.

There’s a gray area when your EF is between 50% and 55%. Some experts call this borderline.

A normal EF doesn’t always mean your heart is healthy. You could have heart failure with preserved ejection fraction (HFpEF). It happens when your heart muscle thickens to the point that the left ventricle holds less than the usual amount of blood. Even if that chamber pumps the way it should, it doesn’t release as much oxygen-rich blood as your body needs.

What Is a Low Ejection Fraction?

If your doctor says your ejection fraction is too low, under 50%, it means there may be a problem with your heart.

With a low ejection fraction, you might have:

• Fatigue (feeling tired all the time)
• Shortness of breath
• Rapid heartbeat
• Swollen feet, legs, or belly

Causes of Low Ejection Fraction

A low ejection fraction could also be a sign of a condition such as:

• Damage from a heart attack
• Heart muscle diseases (cardiomyopathy)
• Heart valve problems
• High blood pressure that hasn’t been under control for a long time

Low Ejection Fraction Treatment

Medications can raise your ejection fraction and make you feel better. Your doctor may suggest:

• Inotropes like digoxin. They help your heart contract better.
• Angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), or angiotensin receptor neprilysin inhibitors (ARNIs) like sacubitril/valsartan(Entresto). They ease stress on your heart muscle.
• Beta-blockers. They ease symptoms by slowing your heart rate a bit to lower its workload.
• Diuretics. They help your body get rid of extra fluid from swelling.
• Mineralocorticoid receptor antagonists. These diuretics help your body get rid of salt and fluid without losing potassium.

You might also need to make lifestyle changes such as:

• Get regular physical activity at a level your doctor approves.
• Take daily relaxation or rest periods.
• Limit salt and excess fluids.
• Cut out alcohol and tobacco.

• What does my ejection fraction number mean for my health?
• When should I have my EF tested again?
• Should I take medications or make lifestyle changes?
• Do I need any other tests?
• Do you specialize in heart rhythm problems? If not, should I see a doctor who does?

What Is a High Ejection Fraction?

If your ejection fraction is higher than 75%, it could be a sign of a condition called hypertrophic cardiomyopathy. It causes the walls of your heart to beat harder. They become thick and stiff, and your heart doesn’t take in or pump out as much blood as usual.