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the fraction of the blood contained in the ventricle at the end of diastole that is expelled during its contraction, that is, the stroke volume divided by end-diastolic volume, normally 0.55 (by electrocardiogram) or greater; with the onset of congestive heart failure, the ejection fraction decreases, sometimes to 0.10 or even less in severe cases.
ejection fraction (EF)
the fraction of the total ventricular filling volume that is ejected during each ventricular contraction. The normal EF of the left ventricle is 65%.
ejection fractionLeft ventricular ejection fraction Cardiology The percentage of blood present in the left ventricle that is effectively pumped forward during systole to supply the peripheral circulation. See Congestive heart failure.
e·jec·tion frac·tion(EF) (ē-jek'shŭn frak'shŭn)
The fraction of blood contained in the ventricle at the end of diastole that is expelled during its contraction.
ejection fractionThe ratio of the stroke volume to the end diastolic volume in the ventricles of the heart. In the healthy heart the volume of blood in the left ventricle at the end of diastole is approximately 140 ml and the stroke volume is about 90 ml. The ejection fraction (stroke volume/end-diastolic volume) is between 50 and 70 per cent. The ejection fraction of the right ventricle is similar. Ejection fraction is not a good predictor of clinical disability. See also DIASTOLIC HEART FAILURE.
The fraction of all blood in the ventricle that is ejected at each heartbeat. One of the main advantages of the MUGA scan is its ability to measure ejection fraction, one of the most important measures of the heart's performance.
in echocardiography, the fractional volume of blood leaving the left ventricle in systole.