What is the normal left ventricular ejection fraction (EF) in healthy adults?

• A. About 55% to 70%.
• B. 30% to 40%.
• C. 40% to 50%.
• D. 70% to 85%.

Answer: (A)

Left ventricular ejection fraction is a measure of how much blood the left ventricle pumps out with each heartbeat, expressed as a percentage of the volume that fills the ventricle at the end of diastole. In healthy adults, the normal range is about 55% to 70%. This indicates the ventricle is pumping a large portion of the filled blood with each beat, reflecting good systolic function. Values well below this range point to impaired pumping (systolic dysfunction), while an EF in the upper normal end (around 70%) is still considered normal, with values above that being unusually high. EF is typically measured by imaging methods like echocardiography and is calculated as EF = (stroke volume) / (end-diastolic volume).