Ejection Fraction Measurement and Interpretation

Definition and Calculation

The American College of Cardiology defines left ventricular ejection fraction (LVEF) as the proportion of blood ejected during left ventricular contraction of the heart 1
The formula for calculating ejection fraction is: LVEF = ([EDV-ESV]/EDV) × 100, where EDV is the volume of blood in the ventricle at the end of filling and ESV is the volume of blood remaining in the ventricle after contraction 2, 3
EDV is the volume of blood in the ventricle at the end of filling (diastole) 3
ESV is the volume of blood remaining in the ventricle after contraction (systole) 3

LVEF is a key measure of cardiac systolic function and serves as a critical parameter for diagnosis, prognosis, and treatment decisions, according to the American College of Cardiology and the American Heart Association 1, 2
Normal LVEF typically ranges from 50-70% 4
The American College of Cardiology/American Heart Association classifies LVEF as:
- Normal: Left ventricular systolic function is normal 2
- Hyperdynamic: Greater than normal proportion of blood is ejected during systole 1
- Mildly reduced: The proportion of blood ejected is slightly reduced compared to normal 5
- Moderately reduced: The proportion of blood ejected is moderately smaller than normal 5
- Severely reduced: The proportion of blood ejected is considerably less than normal 5

LVEF is used to categorize heart failure types, with the American College of Cardiology recommending its use in this context 6
LVEF can be estimated visually by echocardiography or calculated using volumetric measurements, as recommended by the American College of Cardiology 1, 2
Right ventricular ejection fraction (RVEF) can also be measured and has similar clinical significance for right heart function, according to the American College of Cardiology 5

EF has several limitations, including variation between different imaging modalities and interpreters, as noted by the American College of Cardiology 6