Heart Health Understanding the Heart

What is Ejection Fraction and Why is it Important?

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Summary & Participants

How does the amount of blood you heart pump affect your health? Get the facts about this key function of the heart.

Medically Reviewed On: July 21, 2012

Webcast Transcript

ANNOUNCER: In understanding how the heart works, it important to know the meaning of the term "ejection fraction."

ERIC MICHELSON, MD: The heart is a very effective pump, and under normal conditions every time the heart fills with blood, the pumping chambers, the major chambers, the ventricles, eject that blood into the major blood vessels. Ejection fraction is a measure of the pumping function of the heart. At rest, a normal person may have an ejection fraction of approximately 55 percent. That means when the pump is full and contracts, 55 percent of the blood that was in the heart before it began to contract is now ejected.

JACQUELINE NOONAN, MD: When you're not able to maintain that normal level, it's usually because your heart is not functioning well as a pump. Because, remember, the heart is a pump. It's a muscle that pumps blood and, when your ejection fraction is low, it means the pump isn't working as well as it should.

NANETTE KASS-WENGER, MD: The lower the ejection fraction, the worse the pumping function of your heart, and ejection fractions lower than 30 or 35 percent have a number of adverse consequences on your health.