Understanding ejection fraction

Ask the doctor

Q. My doctor wants to measure my ejection fraction. What does that mean, and what should I expect?

A. With every heartbeat, your heart contracts and relaxes. During the contraction, the heart's main pumping chamber, the left ventricle, ejects blood out to the rest of the body. When your heart relaxes, the ventricle refills with blood. The ejection fraction is the percentage of blood leaving the chamber each time it contracts.

To continue reading this article, you must login.
  • Research health conditions
  • Check your symptoms
  • Prepare for a doctor's visit or test
  • Find the best treatments and procedures for you
  • Explore options for better nutrition and exercise
Learn more about the many benefits and features of joining Harvard Health Online »