Normal Ejection Fraction Range
The normal left ventricular ejection fraction (LVEF) range is 50% to 70%, with a midpoint of 60%, according to current American College of Cardiology/American Heart Association guidelines. 1, 2
Standard Classification System
The ACC/AHA defines LVEF categories as follows:
- Hyperdynamic: Greater than 70% 1, 2
- Normal: 50% to 70% (midpoint 60%) 1, 2
- Mildly reduced: 40% to 49% 1, 2
- Moderately reduced: 30% to 39% 1, 2
- Severely reduced: Less than 30% 1, 2
The lower limit of normal LVEF is generally accepted as 50%, with values below this threshold indicating some degree of left ventricular systolic dysfunction. 2
Alternative Reference Ranges by Imaging Modality
The specific normal range varies depending on the imaging technique used:
- 2D Echocardiography (Biplane Simpson's method): 53% to 73% (mean 63 ± 5%) according to the European Society of Cardiology 1
- 3D Echocardiography: 52% to 72% for women (mean 62 ± 5%) 1
- Cardiac MRI for men aged 20-80 years: 57% to 77% 3
The European Society of Cardiology recommends using the biplane method of discs (modified Simpson's rule) as the standard measurement technique, which is particularly reliable in abnormally shaped ventricles. 1
Important Clinical Considerations
Measurement variability is substantial and clinically relevant. LVEF measurement varies between imaging modalities and interpreters, with potential differences of 5-7% between studies due to technical factors rather than actual changes in cardiac function. 1, 2 A single LVEF measurement at one time point may not be adequate, particularly for borderline values in the mildly reduced range (41-49%). 1
The "low normal" designation (50-55%) carries prognostic significance. Research demonstrates that asymptomatic individuals with LVEF of 50-55% have a 3.64-fold increased risk of developing congestive heart failure compared to those with LVEF ≥55%, though mortality risk is not significantly elevated. 4
Special Populations and Contexts
For young adults and athletes: An ejection fraction ≥50% is considered adequate for all activities, including competitive athletics. 1, 3 Up to 15% of trained athletes may have ejection fractions as low as 45% due to physiological cardiac remodeling from systematic training, representing athletic heart adaptation rather than pathology. 3
Hyperdynamic states require clinical correlation. Values >70% may be seen in hyperdynamic circulation states (such as cirrhosis), hypovolemia, small ventricular cavity, or compensatory mechanisms like mitral regurgitation. 1, 2 An LVEF of 75% should be considered normal to mildly hyperdynamic but requires assessment of clinical context, ventricular size, and volume status. 1
Common Pitfalls to Avoid
Do not assume higher LVEF always means better cardiac function. LVEF is load-dependent and cannot distinguish between preload, afterload, and intrinsic contractility. 1 Elderly women with very high LVEF (>65%) after acute coronary syndromes have paradoxically increased mortality compared to those with normal LVEF (55-65%). 5
Avoid relying on geometric assumptions. Linear measurements (Teichholz or Quinones methods) are not recommended as they depend on geometric assumptions that fail in abnormally shaped ventricles. 1 The biplane Simpson's method is preferred for accuracy. 1
Consider alternative metrics when EF appears preserved but dysfunction is suspected. Global longitudinal strain (GLS) can detect subclinical LV dysfunction before EF impairment, with values <-16% indicating mild depression and <-10% severe reduction. 1