55-70%
The left ventricle is the heart's main pumping chamber, so ejection fraction is usually measured only in the left ventricle (LV). An LV ejection fraction of 55 percent or higher is considered normal. An LV ejection fraction of 50 percent or lower is considered reduced. Ejection fraction is usually expressed as a percentage. A normal heart pumps a little more than half the heart’s blood volume with each beat. (1). A normal LVEF ranges from 55-70%. A LVEF of 65, for example, means that 65% of the total amount of blood in the left ventricle is pumped out with each heartbeat. The LVEF may be lower when the heart muscle has become damaged due to a heart attack, heart muscle disease (cardiomyopathy), or other causes. Ejection fraction is a test that determines how well your heart pumps with each beat. Left ventricular ejection fraction (LVEF) is the measurement of how much blood is being pumped out of the left ventricle of the heart (the main pumping chamber) with each contraction. Ejection fraction (EF) is the fraction of outbound blood pumped from the heart with each heartbeat. It is commonly measured by echocardiogram and serves as a general measure of a person's cardiac function. Ejection fraction is typically low in patients with Systolic congestive heart failure. Ejection fraction is a similar but distinct mathematical model when compared to stroke volume, which (along with heart rate) determines cardiac output, which is the amount of blood the heart pumps per minute. When when heart relaxes, the ventricles refill with blood. The ejection fraction (EF) refers to the amount, or percentage, of blood that is pumped (or ejected) out of the ventricles with each contraction. Ejection fraction is a measurement of the percentage of blood leaving your heart each time it contracts. During each heartbeat cycle, the heart contracts and relaxes. When your heart contracts, it ejects blood from the two pumping chambers (ventricles). When your heart relaxes, the ventricles refill with blood.
http://www.mayoclinic.org/ejection-fraction/expert-answers/FAQ-20058286 http://my.clevelandclinic.org/services/heart/disorders/heart-failure-what-is/ejectionfraction http://my.clevelandclinic.org/services/heart/disorders/heart-failure-what-is/ejectionfraction https://en.wikipedia.org/wiki/Ejection_fraction http://www.hrsonline.org/Patient-Resources/The-Normal-Heart/Ejection-Fraction http://www.mayoclinic.org/ejection-fraction/expert-answers/FAQ-20058286
what is a normal ejection fraction range