Left Ventricular Ejection Fraction: Measurement Methods

Left ventricular ejection fraction (LVEF) is one of the most frequently reported echocardiographic measurements, and one of the most consequential — it drives diagnosis, prognosis, and treatment decisions across cardiology. This tutorial focuses specifically on how EF is measured and where each method can go wrong. For the broader picture of LV systolic function beyond EF alone — wall motion scoring, dP/dt, tissue Doppler, and strain — see the Left Ventricular Systolic Function tutorial.

What Ejection Fraction Measures

EF is the fraction of the end-diastolic left ventricular volume ejected with each contraction:

EF (%) = [(EDV − ESV) ÷ EDV] × 100

where EDV is end-diastolic volume and ESV is end-systolic volume. It is a measure of global systolic function, not a direct measure of contractility, stroke volume, or cardiac output — a ventricle can have a normal EF with significantly reduced stroke volume if it is small, or the reverse in a dilated ventricle. EF is also a genuinely different measurement from regional wall motion scoring — the two are read together, not as substitutes for each other; see Coronary Territories and Infarct Localization for how segment-level findings translate into a specific culprit vessel.

Normal Ranges — Worth Getting Right

Current ASE/EACVI chamber quantification standards give the following normal ranges and severity partitions, and they’re narrower than some older reference tables still in circulation (a “48–78%” normal range, for instance, is outdated):

Severity	Male	Female
Normal	52–72%	54–74%
Mildly reduced	41–51%	41–53%
Moderately reduced	30–40%	30–40%
Severely reduced	< 30%	< 30%

Visual Estimation

Experienced readers commonly estimate EF “by eye,” integrating an overall impression of wall motion and cavity size change across multiple views. In experienced hands, visual estimation correlates reasonably well with quantitative methods, particularly at the extremes (clearly normal or clearly severely reduced function). Agreement is weaker in the moderate-dysfunction range, where the visual difference between, for example, an EF of 40% and 45% is subtle and clinically significant.

Simpson’s Biplane Method of Discs

The modified Simpson’s biplane method is the standard, guideline-recommended 2D quantitative approach. The endocardial border is traced at end-diastole and end-systole in both the apical four-chamber and apical two-chamber views. The software divides the traced cavity into a stack of discs of equal height and sums their individual volumes (each treated as a cylinder) to estimate total LV volume at each time point — hence “method of discs.”

Accurate tracing requires:

• Non-foreshortened apical views, with the true LV apex — not a foreshortened, artificially blunted apex — included in the tracing.
• Careful border tracing that follows the blood-tissue interface, excluding papillary muscles from the cavity trace.
• Adequate endocardial definition; contrast enhancement should be considered when border definition is poor in two or more contiguous segments — see Contrast Echocardiography for agent selection and imaging technique.

The Teichholz (M-Mode) Method

Before 2D methods became standard, EF was commonly estimated from a single M-mode measurement of the LV internal dimension at end-diastole and end-systole (LVIDd and LVIDs), using a geometric formula (the Teichholz method) that assumes the LV is a predictably shaped ellipsoid contracting uniformly.

This assumption is the method’s core weakness: it holds reasonably well in a normally shaped, globally contracting ventricle, but breaks down with any regional wall motion abnormality or distorted LV geometry — exactly the situations where an accurate EF often matters most clinically. The Teichholz method is fast and still useful as a quick cross-check or when 2D image quality is limited, but Simpson’s biplane (or 3D, where available) is preferred whenever accuracy is important and image quality allows it.

The Area-Length Method

A less commonly used 2D alternative to Simpson’s biplane, the area-length method estimates LV volume from the traced cavity area in a single short-axis view combined with the LV long-axis length, assuming a bullet-shaped (ellipsoid) ventricle. Like the Teichholz method, its geometric assumption is a source of error with an abnormally shaped ventricle, which is part of why Simpson’s biplane — which doesn’t depend on a single assumed shape — is the preferred standard method where feasible.

Common Sources of Error

• Apical foreshortening is the single most common and consequential error. A foreshortened apex makes the ventricle appear shorter and rounder than it truly is, which systematically overestimates EF.
• Poor endocardial border definition, especially in patients with a difficult body habitus, can force the reader to guess at the true border.
• Inconsistent frame selection for true end-diastole and end-systole affects both EDV and ESV, and therefore the calculated EF.
• Papillary muscle inclusion in the traced cavity artificially reduces measured volumes — the same normal structure that’s occasionally mistaken for an abnormal mass; see Approach to Cardiac Masses for the broader differential this fits into.
• Applying a linear-dimension method (Teichholz) to a ventricle with regional wall motion abnormalities, where its uniform-contraction assumption no longer holds — a genuine concern after acute myocardial infarction specifically, where biplane Simpson’s should be used instead.

Beyond 2D: 3D Echocardiography and Strain

Three-dimensional echocardiography measures LV volumes without relying on the geometric assumptions of 2D methods and without the foreshortening risk inherent to a single 2D plane, and is increasingly preferred where image quality and equipment allow — see Three-Dimensional Echocardiography for how these volumes are acquired and their own accuracy caveats. Global longitudinal strain (GLS), derived from speckle-tracking analysis, offers a complementary, often more reproducible measure of systolic function that can detect subclinical dysfunction before EF declines — see the Left Ventricular Systolic Function tutorial for a fuller discussion of GLS, along with wall motion scoring, dP/dt, and tissue Doppler parameters that round out a comprehensive systolic function assessment beyond EF alone. See Introduction to Diseases of the Myocardium for how EF fits into distinguishing the cardiomyopathy phenotypes — a normal EF, for instance, doesn’t rule out hypertrophic or restrictive disease.