Back to Glossary
Left Ventricular Ejection Fraction
Ejection fraction measured for the left ventricle specifically. The reference parameter for systolic function and heart-failure phenotyping.
LVEF is the percentage of blood pumped out of the left ventricle with each beat. It is the most widely used systolic-function measurement in echocardiography.
International heart-failure guidelines use LVEF cut-offs to classify the syndrome: HFrEF (reduced, ≤40%), HFmrEF (mildly reduced, 41–49%), and HFpEF (preserved, ≥50%). Each phenotype carries distinct diagnostic criteria and treatment pathways.
Automated LVEF derived from AI tracing of multiple loops is more reproducible than manual single-loop tracing and is increasingly used as the basis for serial heart-failure monitoring.