EF

Ejection fraction: the left ventricle is the heart’s main pumping chamber that pumps oxygenated blood through the ascending (upward) aorta to the rest of the body, so the ejection fraction is usually measured only in the left ventricle (LV). An LV ejection fraction of 55 percent or higher is considered normal. The EF is the percent of volume of blood in the LV when it is full which is ejected when the heart pumps.