How this calculator works
Ejection fraction is the fraction of end-diastolic ventricular volume expelled during a beat. Subtracting end-systolic from end-diastolic volume gives total stroke volume. The flow method substitutes forward cardiac output divided by heart rate, which may disagree with total ventricular stroke volume when there is significant regurgitation or shunting. The result is an estimate for information only and is not medical advice.
Formula
EF = (EDV - ESV)/EDV = SV/EDV. SV(mL) = CO(L/min) × 1000/HR; EDV = SV/EF; ESV = EDV(1-EF).
Worked example
EDV 120 mL and ESV 50 mL give SV 70 mL and EF 58.33%. EDV 100 mL and SV 60 mL give EF 60%.
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Frequently asked questions
Is EF a percentage of all blood in the body?
No. It is the fraction of ventricular end-diastolic volume ejected in one beat.
Can EF exceed 100%?
These volume definitions cannot produce an EF above 100%; inconsistent inputs are rejected.
Does a preserved EF rule out heart failure?
No. Heart failure can occur with preserved EF and needs a clinical assessment.