- Ejection fraction
- The portion of blood that is pumped out of a filled ventricle as a result of a heartbeat. The heart does not eject all of the blood that is in the ventricle. Only about two-thirds of the blood is normally pumped out with each beat. That fraction is referred to the ejection fraction. The ejection fraction is an indicator of the heart's health. If the heart is diseased from a heart attack or another cardiac condition, the ejection fraction may fall, for example, to a third. Only a third of the blood in the ventricle (half the normal two-thirds) is pumped out. The heart is essentially half-normal (in this respect).
* * *ejection fraction n the ratio of the volume of blood the heart empties during systole to the volume of blood in the heart at the end of diastole expressed as a percentage usu. between 50 and 80 percent
* * *the proportion of the volume of blood in the ventricles at the end of diastole that is ejected during systole; it is the stroke volume divided by the end-diastolic volume, often expressed as a percentage. It is normally 65 ± 8 per cent; lower values indicate ventricular dysfunction.
Medical dictionary. 2011.