Is a transesophageal echocardiogram (TEE) needed to evaluate left ventricular ejection fraction (LVEF)?

TEE is NOT needed to evaluate LVEF

Transthoracic echocardiography (TTE) is the preferred and recommended initial imaging modality for evaluating left ventricular ejection fraction, and transesophageal echocardiography (TEE) should not be used routinely for this purpose. 1

Why TTE is the Standard for LVEF Assessment

The most recent ACR Appropriateness Criteria (2025) explicitly states that there is limited evidence to support the use of TEE as an initial imaging modality to establish or confirm a diagnosis of heart failure 1. Multiple studies have demonstrated the value of TTE-derived measures of cardiac structure and function, and multisociety consensus guidelines list TTE as the preferred initial test in patients with suspected heart failure 1.

TTE provides:

• Non-invasive assessment with reliable information in most cases 2
• Excellent correlation with LVEF measurements when compared to other modalities 3, 4
• Adequate visualization for LVEF quantification using Simpson's method or other validated formulas 5

When TEE May Be Considered (Not for Routine LVEF)

TEE has specific, limited indications that are not primarily for LVEF evaluation:

In ARDS/Critical Care Settings

• When TTE is limited by poor echogenicity 2
• For more accurate detection of acute cor pulmonale (comparing RV to LV end-diastolic areas) 2
• The echocardiographic examination should be completed by determination of LVEF, but this is ancillary to the primary indication 2

In Pulmonary Hypertension

• TEE is more invasive and requires conscious sedation 6, 7
• May be used to evaluate intracardiac shunts, but noninvasive techniques such as cardiac MRI and CT are recommended over TEE 6, 7

In Cardiac Surgery

• Intraoperative TEE can measure LVEF and guide surgical decisions 8
• Real-time 3D TEE makes intraoperative LVEF measurements feasible 9
• However, this is an intraoperative monitoring context, not outpatient diagnostic evaluation

Important Caveats About TEE for LVEF

Research shows that while TEE can measure LVEF, it has significant limitations:

1. Underestimation of volumes: TEE-derived ventricular volumes are significantly smaller than angiographic measurements, likely due to foreshortening in the four-chamber view 3

2. Cannot assess entire left atrium: With TEE, the entire left atrium frequently cannot fit in the image sector, so TEE should not be used to assess LA size 5

3. Altered hemodynamics: LVEF can increase during TEE in patients with impaired ventricular function (over 50% of such patients), potentially affecting measurements 10

4. No role in routine follow-up: There is limited evidence for TEE in routine follow-up of patients with known heart failure 1

Clinical Algorithm for LVEF Evaluation

Step 1: Perform TTE as the initial test

• Use Simpson's biplane method for LVEF quantification
• Consider IV contrast if 2 or more contiguous LV segments are poorly visualized 1

Step 2: If TTE windows are inadequate or results are discordant with clinical presentation:

• Consider cardiac MRI (provides more reproducible LVEF measurements and tissue characterization) 1
• TEE is not the next step for LVEF assessment

Step 3: Reserve TEE only for:

• Specific valvular assessment needs
• Intraoperative monitoring
• Evaluation of endocarditis or intracardiac masses
• Assessment when TTE is inadequate AND the clinical question requires information beyond LVEF (e.g., detailed valvular morphology, source of embolism)